Oncogene database

2064

ERBB2

erb-b2 receptor tyrosine kinase 2;ERBB2;erb-b2 receptor tyrosine kinase 2

c-erb B2/neu protein|herstatin|human epidermal growth factor receptor 2|metastatic lymph node gene 19 protein|neuro/glioblastoma derived oncogene homolog|neuroblastoma/glioblastoma derived oncogene homolog|p185erbB2|proto-oncogene Neu|proto-oncogene c-Erb

17q12

protein-coding

In order to evaluate the involvement of c-yes and c-erbB-2 oncogene products, and p53 tumor suppressor protein in canine mammary neoplastic lesions, sections of archived paraffin-embedded samples of 79 mammary tumors were analyzed immunohistochemically using antibodies against human c-yes p62 and c-erbB-2 products and p53. These 79 tumors were divided into 2 groups: 32 benign (2 adenosis, 7 simple adenomas, 14 complex adenomas, and 9 benign mixed mammary tumors) and 47 malignant tumors (26 simple adenocarcinomas, 7 complex adenocarcinomas, 5 solid carcinomas, 2 sclerosing carcinomas, 6 malignant mixed mammary tumors, and 1 malignant myoepithelioma). As a result of immunostaining, 40.6% (13/32) of the benign tumors and 21.3% (10/47) of the malignant tumors expressed the c-Yes oncogene product, ErbB-2 expression was detected in 50% (16/32) of the benign tumors and in 19.1% (9/47) of the malignant tumors. P53 expression was detected in 16% (4/25) of the benign tumors and in 30.6% (11/36) of the malignant tumors. Co-expression of c-Yes and ErbB-2, ErbB-2 and p53, and ALL 3 products was detected in 6, 1 and 7 tumors, respectively.

Oncogenes are important cellular genes that in general promote in the normal growth regulatory pathways. The human c-erb B-2 proto-oncogene (HER-2 or neu) encodes a 185 kDa transmembrane putative growth factor receptor of the tyrosine kinase family. This oncogene has been shown to be over expressed and/or amplified in primary carcinoma of the breast, ovary, pancreas and salivary glands. This study was conducted to evaluate a possible link between amplification of c-erb B-2 oncoprotein and cartilage invasion in laryngeal carcinoma. In addition, data concerning overexpression were compared to other clinicopathological parameters as well as clinical outcomes. In all, 34 patients with squamous cell carcinoma of the larynx were studied prospectively. Total laryngectomy specimens were sliced in horizontal sections at 4- to 5-mm intervals. Specimens were preserved in 10% formalin, and histopathological examinations were carried out after embedding tissues in paraffin sections and then staining them with hematoxylin and eosin. Detection of c-erb B-2 oncoprotein overexpression was carried out with a polyclonal antibody and an avidin-biotin kit. The level of c-erb B-2 overexpression was determined using the Quantimet 520 Leica image analyzing system. However, no significant correlation was found between cartilage invasion and clinicopathological parameters and prognosis. Overexpression of c-erb B-2 attained no significant correlation with clinicopathological parameters. In contrast, the correlation of c-erb B-2 overexpression and cartilage invasion was statistically significant (P = 0.034). In general, overexpression of c-erb B-2 oncoprotein was related to the more aggressive tumors with high capability of invading laryngeal cartilages. Patients with +ve c-erb B-2 oncogene had a poor prognosis but this was not statistically significant when compared to the clinical outcomes of patients with the -ve c-erb B-2 oncogene.

Epithelial cells from non-cancerous mammary tissue in response to exposure to chemical carcinogens or transfection with oncogenes exhibit hyperproliferation and hyperplasia prior to the development of cancer. Aberrant proliferation may, therefore, represent a modifiable early occurring preneoplastic event that is susceptible to chemoprevention of carcinogenesis. The synthetic retinoid N-(4-hydroxyphenyl)retinamide (HPR), has exhibited preventive efficacy in several in vitro and in vivo breast cancer models, and represents a promising chemopreventive compound for clinical trials. Clinically relevant biochemical and cellular mechanisms responsible for the chemopreventive effects of HPR, however, are not fully understood. Experiments were performed on preneoplastic human mammary epithelial 184-B5/HER cells derived from reduction mammoplasty and initiated for tumorigenic transformation by overexpression of HER-2/neu oncogene, to examine whether HPR inhibits aberrant proliferation of these cells and to identify the possible mechanism(s) responsible for the inhibitory effects of HPR. Continuous 7-day treatment with HPR produced a dose-dependent, reversible growth inhibition. Long-term (21 day) treatment of 184-B5/HER cells with HPR inhibited anchorage-dependent colony formation by approximately 80% (P < 0.01) relative to that observed in the solvent control. A 24 h treatment with cytostatic 400 nM HPR produced a 25% increase (P = 0.01) in G0/G1 phase, and a 36% decrease (P = 0.01) in S phase of the cell cycle. HPR treatment also induced a 10-fold increase (P = 0.02) in the sub-G0 (apoptotic) peak that was down-regulated in the presence of the antioxidant N-acetyl-L-cysteine. Treatment with HPR resulted in a 30% reduction of cellular immunoreactivity to tyrosine kinase, whereas immunoreactivity to p185HER remained essentially unaltered. HPR exposure resulted in time-dependent increase in cellular metabolism of the retinoid as evidenced by increased formation of the inert metabolite N-(4-methoxyphenyl)-retinamide (MPR) and progressive increase in apoptosis. Thus, HPR-induced inhibition of aberrant proliferation may be caused, in part, by its ability to inhibit HER-2/neu-mediated proliferative signal transduction, retard cell cycle progression and upregulate cellular apoptosis.

HER-2/neu gene amplification and protein overexpression have been associated with prognosis in breast, lung and prostate cancers but have not been extensively studied in ovarian carcinoma. For the study, we selected 5-micron-thick, formalin-fixed, paraffin-embedded tissue sections from 74 cases of ovarian epithelial tumors of low malignant potential and ovarian carcinoma. tumors were graded and staged and evaluated for amplification of the HER-2/neu gene by fluorescence in situ hybridization. HER-2/neu amplifications was present in 3 of 13 serous, mucinous, and endometrioid epithelial tumors of low malignant potential and in 40 of 61 epithelial carcinomas. In the carcinoma group, amplification did not correlate with stage, grade, or tumor type. Mean follow-up was 31 months; 1 patient with a low malignant potential tumor and 32 patients with carcinomas died of disease. On univariate and multivariate analysis, survival correlated with stage of disease but not with HER-2/neu amplification. HER-2/neu amplification by fluorescence in situ hybridization can be performed on tissue sections of ovarian neoplasms; amplification is uncommon in ovarian tumors of low malignant potential, but is present in 66% of ovarian epithelial carcinomas. HER-2/neu amplification did not predict outcome in ovarian epithelial neoplasia but may have an important role in tumor development.

The management of human breast cancer frequently includes radiation therapy as an important intervention, and improvement in the clinical efficacy of radiation is desirable. Overexpression of the HER-2 growth factor receptor occurs in 25-30% of human breast cancers and correlates with poor clinical outcome, including earlier local relapse following conservative surgery accompanied by radiation therapy. In breast cancer cells with overexpression of HER-2 receptor, recombinant humanized monoclonal antibodies (rhuMAbs) to HER-2 receptors (rhuMAb HER-2) decrease cell proliferation in vitro and reduce tumor formation in nude mice. Therapy with rhuMAb HER-2 enhances tumor sensitivity to radiation at doses of 1-5 Gy, exceeding remission rates obtained with radiation alone. This benefit is specific to cells with HER-2 overexpression and does not occur in cells without overexpression. Treatment of cells with radiation (2-4 Gy) alone provokes a marked increase in unscheduled DNA synthesis, a measure of DNA repair, but HER-2-overexpressing cells treated with a combination of rhuMAb HER-2 and radiation demonstrate a decrease of unscheduled DNA synthesis to 25-44% of controls. Using an alternate test of DNA repair, i.e., radiation-damaged or undamaged reporter DNA, we introduced a cytomegalovirus-driven beta3-galactosidase into HER-2-overexpressing breast cancer cells that had been treated with rhuMAb HER-2 or control. At 24 h posttransfection, the extent of repair assayed by measuring reporter DNA expression was high after exposure to radiation alone but significantly lower in cells treated with combined radiation and rhuMAb HER-2 therapy. To further characterize effects of rhuMAb HER-2 and the combination of antibody and radiation on cell growth, analyses of cell cycle phase distribution were performed. Antibody reduces the fraction of HER-2-overexpressing breast cancer cells in S phase at 24 and 48 h. Radiation treatment is also known to promote cell cycle arrest, predominantly at G1, with low S-phase fraction at 24 and 48 h. In the presence of rhuMAb HER-2, radiation elicits a similar reduction in S phase at 24 h, but a significant reversal of this arrest appears to begin 48 h postradiation exposure. The level of S-phase fraction at 48 h is significantly greater than that found at 24 h with the combined antibody-radiation therapy, suggesting that early escape from cell cycle arrest in the presence of antireceptor antibody may not allow sufficient time for completion of DNA repair in HER-2-overexpressing cells. Because it is well known that failure of adequate p21WAF1 induction after DNA damage is associated with failure of cell cycle arrest, we also assessed the activity of this critical mediator of the cellular response to DNA damage. The results show induction of p21WAF1 transcripts and protein product at 6, 12, and 24 h after radiation treatment; however, increased levels of p21WAF1 transcript and protein are not sustained in HER-2-overexpressing cells exposed to radiation in the presence of rhuMAb HER-2. Although transcript and protein levels increase at 6-12 h, they are both diminished by 24 h. Levels of p21WAF1 transcript and protein at 24 h are significantly lower than in cells treated by radiation without antibody. A reduction in the basal level of p21WAF1 transcript also occurred after 12-24 h exposure to antibody alone. The effect of HER-2 antibody may be related to tyrosine phosphorylation of p21WAF1 protein. Tyrosine phosphorylation of p21WAF1 is increased after treatment with radiation alone, but phosphorylation is blocked by combined treatment with antireceptor antibody and radiation. This dysregulation of p21WAF1 in HER-2-overexpressing breast cells after treatment with rhuMAb HER-2 and radiation appears to be independent of p53 expression levels but does correlate with reduced levels of mdm2 protein. (ABSTRACT TRUNCATED)FAU - Pietras, R J

The HER-2/neu oncogene encodes a transmembrane tyrosine kinase receptor with extensive homology to the epidermal growth factor receptor. HER-2/neu has been widely studied in breast cancer. The potential value of HER-2/neu status for the prediction of disease outcome and response to therapy in breast cancer is presented in the light of a series of recently published studies showing a range of impact on the outcome of patients treated with hormonal, cytotoxic and radiation therapies. This review includes the application of serum-based HER-2/neu testing and the use of antibody-based therapies directed against the HER-2/neu protein and their potential to become a new modality for breast cancer treatment.

TAB-250 and BACH-250 are murine and human chimeric antibodies directed at the extracellular domain of the gp185c-erb-2 (HER2/neu) growth factor receptor overexpressed in a variety of tumor types, including ovarian and breast carcinoma. The ribosome-inhibiting plant toxin gelonin (rGel) was chemically coupled to both antibodies, and the resulting immunotoxins were purified and tested in vitro against human tumor cells expressing various levels of HER-2/neu and in vivo against human tumor xenograft models. The binding of both BACH-250 and BACH-250/rGel conjugate to target cells was essentially equivalent. Against SKOV-3 cells, the IC50 of BACH-250/rGel was 97 pM (17 ng/ml), whereas BACH-250 and rGel alone showed no cytotoxic effects. There was a clear correlation between expression levels of HER-2/neu and cytoimmunotoxin. Tissue distribution studies showed that the antibody and immunotoxin both concentrate 2-10-fold higher in tumors than in normal tissues, with optimal tumor uptake occurring 48-96 h after administration. Plasma clearance curves for BACH-250 and BACH-250/rGel showed terminal-phase half-lives of 26 and 72 h, respectively. In athymic mice bearing s.c. or i.p. SKOV-3 tumors, immunotoxin treatment slowed tumor growth by 99 and 94 % at days 35 and 49 after implantation, respectively, and lengthened the median survival by 40% (from 30 to 50 days) in mice bearing lethal i.p. tumors. We conclude that clinical development of BACH-250/rGel may be warranted in patients with HER2/neu-expressing malignancies.

Several components of the eukaryotic protein synthesis apparatus have been associated with oncogenic transformation of cells. Altered expression of translation elongation factor 1 alpha (EF-1 alpha), a core component of protein synthesis and closely related sequences have been linked with transformed phenotypes by several independent studies, in diverse systems. A dominant acting oncogene, prostate tumor inducing gene-1 (PTI-1) has provided further evidence for this link. PTI-1 appears to be a hybrid molecule with components derived from both prokaryotic and eukaryotic origins. The predicted protein coding moiety represents an EF-1 alpha molecule, truncated N-terminal to amino acid residue 68 and having six additional point mutations. This coding sequence is fused to a 5 untranslated region (UTR) showing strongest homology to ribosomal RNA derived from Mycoplasma hyopneumoniae. expression studies using the cloned cDNA in nude mouse tumor formation assays have confirmed the oncogenic nature of the molecule. A broad spectrum of tumor derived cell lines, from varied tissue sources and blood samples from patients having confirmed prostate carcinoma, ALL scored positive for expression of PTI-1, while corresponding normal tissues or blood samples were negative. Based on its near identity to EF-1 alpha, it is proposed that PTI-1 represents a new class of oncogene whose transforming capacity probably arises through mechanisms including: (i) protein translational infidelity, resulting in the synthesis of mutant polypeptides due to loss of proofreading function during peptide chain elongation, (ii) by its association with and alteration of the cytoskeleton, (iii) by impinging on one particular or several different signal transduction pathways through its properties as a G-protein.

The erbB-2/HER2 oncogene is overexpressed in a significant fraction of human carcinomas of the breast, ovary, and lung in a manner that correlates with poor prognosis. Although the encoded protein resembles several receptors for growth factors, no high affinity ligand of ErbB-2 has so far been fully characterized. However, several lines of evidence have raised the possibility that ErbB-2 can augment signal transduction initiated by binding of certain growth factors to their direct receptors. Here, we contrasted these two models of ErbB-2 function: First, examination of a large series of epidermal growth factor (EGF)-like ligands and neuregulins, including virus-encoded ligands as well as related motifs derived from the precursor of EGF, failed to detect interactions with ErbB-2 when this protein was singly expressed. Second, by using antibodies that block inter-ErbB interactions and cells devoid of surface ErbB-2, we learned that signaling by ALL ligands examined, except those derived from the precursor of EGF, was enhanced by the oncoprotein. These results imply that ErbB-2 evolved as a shared receptor subunit of ALL ErbB-specific growth factors. Thus, oncogenicity of ErbB-2 in human epithelia may not rely on the existence of a specific ligand but rather on its ability to act as a coreceptor for multiple stroma-derived growth factors.

BACKGROUND: The prognostic value of the Lauren classification and of c-erbB-2 oncogene overexpression has been described for gastric cancer. The aim of this study was to investigate the clinical significance of these factors in adenocarcinoma of the esophagus and/or gastroesophageal junction (GEJ). METHODS: Forty-one adenocarcinomas of the esophagus and/or GEJ were reviewed for tumor stage, lymph node status, Lauren classification, and c-erbB-2 overexpression, as assessed by immunohistochemical analysis. RESULTS: According to the Lauren classification, tumors were classified as intestinal-, mixed-, or diffuse-type (54%, 32%, and 15%, respectively). Diffuse-type tumors were associated with a significantly worse prognosis than were intestinal-type tumors (P = .018; log-rank test). The prognostic value of the Lauren classification was independent of stage (P = .048; Cox regression model). Overexpression of c-erbB-2 was detected in 24% of the tumors and was present exclusively in intestinal-type tumors and in intestinal-type areas of mixed-type tumors. Ten of the 30 stage III/IV tumors (33%) were c-erbB-2-positive, whereas none of the 11 stage I/II tumors (0%) overexpressed the oncogene product (P = .04; Fisher exact test). The prognostic value of c-erbB-2 overexpression was not independent of stage (P = .7; Cox regression model). CONCLUSIONS: (1) The Lauren classification is an independent prognostic factor in adenocarcinoma of the esophagus and GEJ. (2) c-erbB-2 overexpression is limited to (areas of) intestinal-type tumors, indicating that intestinal- and diffuse-type tumors differ oncogenetically. (3) c-erbB-2 overexpression is associated with the stage of disease, indicating that it is a late event during tumor progression.

The ErbB2 receptor tyrosine kinase (RTK) is expressed in basal cells of squamous epithelia and the outer root sheath of hair follicles. We previously showed that constitutive expression of activated ErbB2 directed to these sites in the skin by the keratin 14 (K14) promoter produces prominent hair follicle abnormalities and striking skin hyperplasia in transgenic mice. However, perinatal lethality precluded the establishment of a transgenic line for analysis of ErbB2 function in adult animals. To investigate the significance of ErbB2 signaling in epithelial tissues during and post development, we developed a K14-rtTA/TetRE-ErbB2 Tet-On bitransgenic mouse system. These mice were normal until the ErbB2 transgene was induced by exposure to doxycycline (Dox). Prenatal induction resulted in perinatal death. Postnatally, ErbB2 transgene expression was observed at 4 h after the initiation of Dox, and reached a plateau at 24 h. Skin hyperplasia followed after 2 days and these changes reverted to normal upon Dox withdrawal. In adults, as in the neonates, prolonged ErbB2 induction caused prominent skin and hair follicle hyperplasias. Severe hyperplasias in the cornea, eye lids, tongue and esophagus were also observed. ErbB2 transgene induction was accompanied by increased expression of TGFalpha, a ligand of epidermal growth factor receptor (EGFR), and to a lesser extent, EGFR, further enhancing RTK signal transduction. We conclude that ErbB2 plays important roles in both development and maintenance of hair follicles and diverse squamous epithelia and that this ligand-inducible and tissue-specific Tet-On transgenic mouse system provides a means to study transgenes with perinatal toxicity.

The HER-2/neu oncogene encodes a transmembrane tyrosine kinase receptor with extensive homology to the epidermal growth factor receptor. HER-2/neu has been widely studied in breast cancer. In this review, the association of HER-2/neu gene and protein abnormalities studied by Southern and slot blotting, immunohistochemistry, enzyme immunoassays, and fluorescence in situ hybridization with prognosis in breast cancer is studied in depth by review of a series of 47 published studies encompassing more than 15,000 patients. The relative advantages of gene amplification assays and frozen/fresh tissue immunohistochemistry over paraffin section immunohistochemistry are discussed. The significance of HER-2/neu overexpression in ductal carcinoma in situ and the HER-2/neu status in uncommon female breast conditions and male breast cancer are also considered. The potential value of HER-2/neu status for the prediction of response to therapy in breast cancer is presented in the light of a series of recently published studies showing a range of impact on the outcome of patients treated with hormonal, cytotoxic, and radiation therapies. The evidence that HER-2/neu gene and protein abnormalities in breast cancer predict resistance to tamoxifen therapy and relative sensitivity to chemotherapy regimens including adriamycin is presented. The review will also evaluate the status of serum-based testing for circulating the HER-2/neu receptor protein and its ability to predict disease outcome and therapy response. In the final section, the review will briefly present preliminary data concerning the use of antibody-based therapies directed against the HER-2/neu protein and their potential to become a new modality for breast cancer treatment. The recently presented phase III clinical trial evidence that systemic administration of anti-HER2 antibodies (Herceptin®), alone and in combination with cytotoxic chemotherapy in patients with HER-2/neu overexpressing primary tumors, can increase the time to recurrence and overall response rates in metastatic breast cancer is reviewed.

HER-2/neu is a "self" tumor antigen that is overexpressed in 15-30% of human adenocarcinomas. Vaccine strategies directed against HER-2/neu and other self tumor antigens require development of methods to overcome immune tolerance to self-proteins. In rats, rat neu peptide vaccines have been shown to be an effective way of circumventing tolerance to rat neu protein and generating rat neu-specific immunity. The present report validates that a similar peptide-based vaccine formulation is effective for inducing T-cell immunity to HER-2/neu protein in humans with breast and ovarian cancer. The vaccine formulation included groups of peptides derived from the HER-2/neu extracellular domain (ECD) or intracellular domain (ICD) mixed with granulocyte macrophage colony stimulating factor as an adjuvant. These peptides were 15-18 amino acids in length and designed to elicit a CD4 T helper-specific immune response. Patients underwent intradermal immunization once a month for a total of two to six immunizations. To date, ALL of the patients immunized with HER-2/neu peptides developed HER-2/neu peptide-specific T-cell responses. The majority of patients (six of eight) also developed HER-2/neu protein-specific responses. Responses to HER-2/neu protein occurred with epitope spreading. Immune T cells elicited by vaccination were shown to migrate outside the peripheral circulation by virtue of generating delayed type hypersensitivity responses distant from the vaccine site, which indicated the potential ability to traffic to the site of tumor. The use of peptide-based vaccines may be a simple, yet effective, vaccine strategy for immunizing humans to oncogenic self-proteins.

Amplification and overexpression of the c-erbB-2 gene has been demonstrated in several tumors and thought to be important determinants of biologic behaviors of carcinomas. In this study, correlation between c-erbB-2 expression und histopathologic parameters, including proliferative activity of gastric carcinomas was evaluated. Paraffin-embedded tissue sections from 62 patients who underwent curative resection of gastric carcinoma were analyzed immunohistochemically for the expression of c-erbB-2 and Ki-67. Strong membrane staining for c-erbB-2 was detected in 11 of 62 gastric carcinomas (17,7%) and no positive reaction was evident in noncancerous tissue. The incidence of c-erbB-2 positivity in intestinal type carcinomas (24,3%) was higher than that of diffuse type carcinomas (4,76%). Positive staining for c-erbB-2 was present in one of the 9 (11,1%) early gastric carcinomas and 10 of 53 (18, 8%) advanced gastric carcinomas. However, no statistically significant relationships were found between c-erbB-2 expression and histopathologic type, depth on invasion, the tumor size or lymph node metastases. Among the metastatic lymph nodes, 3 were positively stained with c-erbB-2 whereas the primary tumors of two cases had been found to be negative. Additionally, no correlation was found between c-erbB-2 reactivity and proliferative activity of carcinoma cells. The results suggest that expression of c-erbB-2 protein may occur selectively in intestinal type of gastric carcinomas. However, c-erbB-2 expression is not a reliable marker of malignant potential in gastric carcinomas.

Overexpression of the c-erbB-2 oncoprotein has been detected in human adenocarcinoma of the breast, cervix and salivary gland, in ALL of which an association between the overexpression of the c-erbB-2 and a poor prognosis of the disease has been reported. However, the prognostic role of c-erbB-2 oncoprotein in ovarian carcinoma remains controversial. We measured c-erbB-2 oncoprotein with an enzyme-linked immunosorbent assay (ELISA). Patients with invasive ovarian cancer were found to have significantly higher median c-erbB-2 oncoprotein expression than patients with either benign ovarian cyst (P = 0.002) or control groups (P = 0.001). Overexpression of c-erbB-2 oncoprotein was found in seven (21.9%) of 32 epithelial ovarian cancers. Our results suggest that quantitative analysis of c-erbB-2 oncoprotein may be used to define the prognostic significance of ovarian carcinoma.

BACKGROUND: Adenoid cystic carcinoma (ACC) of the salivary gland shows a variable clinical course. It would be helpful to discover reliable biologic markers in the management of patients with ACC. METHODS: We examined proliferating cell nuclear antigen (PCNA) and c-erbB-2 oncoprotein expression on 30 cases of ACC of the salivary glands. The immunohistochemical results, and size, location, and histologic grade of the tumors were compared with the clinical outcome of the patients. RESULTS: Mean PCNA positivity of ACCs was 15%, and was higher in solid than in cribriform/tubular areas. High PCNA value was significantly correlated with shorter disease-free and overall survival of the patients with ACC. c-erbB-2 overexpression was observed in only five cases, focally in cribriform/tubular areas. High histologic grade, which was determined by the presence of solid components, showed a trend toward shorter survival. Size and location of ACC were not associated with patient outcome. CONCLUSIONS: The present study indicates that PCNA score may be one of the most useful prognostic factor of ACC.

It is well established that the activation of proto-oncogenes could trigger uncontrolled cell growth and cancer development. Although this correlation has already been evidenced in several human tumors, no conclusive studies have related oncogene activation with the development of prostatic neoplasia. Nevertheless, some reports suggest that c-erbB-2, which is a prognostic marker in breast cancer, could be implicated in the development of prostatic adenocarcinoma. We have studied the expression of the c-erbB-2 oncoprotein in primary prostatic tissue in a series of 70 patients with metastasic disease, by means of immunohistochemistry. The NCL-B 11 anti-c-erbB-2 monoclonal antibody was used, and the immunoreactivity was quantified by image analysis. The overall rate of prostatic-tissue sections presenting positive c-erbB-2 immunostaining was 64.3%. No significant relation was observed between histological grade and c-erbB-2 over-expression or severity of the disease, based on the extent of metastases. The average specific survival in patients with c-erbB-2 over-expression was 33 months, while it was 54 in patients with c-erbB-2 negativity; p < 0. 034. These results, as well as the logistic-regression analysis, suggest that expression of c-erbB-2 oncoprotein would be considered as an independent prognostic factor of metastatic prostate cancer. Moreover, it could discriminate between the prognosis of patients with Gleason score 2 to 7 and those with score 8 to 10. Our results suggest that the expression of c-erbB-2 oncoprotein in primary prostatic tissue could have a prognostic value in patients with metastatic prostate cancer. Int. J. cancer (Pred. Oncol.) 84:421-425, 1999.

The HER-2/neu protein is overexpressed in approximately 20% of human adenocarcinomas and is a defined tumor antigen in breast cancer. The purpose of this study was to evaluate the endogenous HER-2/neu specific antibody response in 57 patients with colorectal cancer. HER-2/neu specific antibodies, titer > or = 1:100, were detected in 14% (8/57) of patients with colorectal cancer compared to none of the normal control population (0/200). Furthermore, detection of HER-2/neu specific antibodies in the cancer population correlated significantly with HER-2/neu protein overexpression in the patients tumor (p < 0.01). 46% of patients with HER-2/neu overexpressing tumors (6/13) and 5% of HER-2/neu negative tumors (2/44) had detectable HER-2/neu specific antibodies. The endogenous HER-2/neu antibody response in these patients was predominantly IgG or IgA.

Oncogene amplification has been implicated in the genesis and progression of many cancers. Overexpression of the HER-2/neu proto-oncogene occurs in 20-30% of ovarian epithelial cancers, in which it may be of prognostic significance. oncogene overexpression is traditionally studied using immunohistochemistry. In this study we used fluorescent in situ hybridization (FISH) to determine HER-2/neu amplification in ovarian papillary serous carcinoma and compared the frequency of amplification in two stages of the disease. Archival tissues from 23 cases of papillary serous ovarian carcinoma (9 cases of stage I and 14 cases of stage III) were analyzed by FISH using a HER-2/neu probe and a chromosome 17 centromere control probe. Determination of the level of amplification was performed according to the standard protocols of the Cytogenetics Laboratory at Rhode Island Hospital. Of the 23 cases successfully analyzed, the frequency of amplification among stage I tumors was 22% (2/9) and the frequency of amplification among stage III tumors was 71% (10/14). These results are significant (P = 0.036). The frequency of stage I tumors among amplified cases was 17% (27/12) and the frequency of stage III tumors among amplified cases was 83% (10/12). This study not only confirms the presence of a subset of ovarian papillary serous carcinoma with HER-2/neu gene amplification, but it also indicates that HER-2/neu oncogene amplification is more likely to be associated with a more advanced stage. Thus, the present data are consistent with the hypothesis that HER-2/neu amplification, similar to HER-2/neu protein over expression, is a prognostic marker of poor outcome.

Prostate cancer is a serious disease affecting men worldwide and treatment compromises the quality of life of prostate cancer patients. We conducted a study of 88 cases of prostate cancer in an attempt to identify prognostic biomarkers that can distinguish aggressive cases that must be treated immediately. HER-2/neu oncogene amplification was initially studied because amplification of this gene has been reported in many other cancers, including those studied in this laboratory. Fluorescence in situ hybridization (FISH) using a HER-2/neu gene probe with a chromosome 17 centromere control probe was performed on formalin-fixed, paraffin-embedded tissues. Of a total of 86 cases successfully analyzed, only 8 (9.3%) were found to be amplified. This frequency was lower than the frequency of amplification found in other cancers studied. Furthermore, no case was found where the level of amplification can be considered high. Only one case was found to have moderate amplification. The rest of the positive cases can ALL be classified as low amplification. Thus, while we have demonstrated that FISH is a sensitive technique for detecting oncogene amplification, the frequency and level of HER-2/neu amplification detected in prostate cancer seem to be lower than those in most cancers that we studied. In view of the fact that HER-2/neu amplification does not seem to play as significant a role, exploration of other biomarkers in prostate cancer is warranted.

Neoadjuvant chemotherapy prior to definitive radical surgery or radiotherapy may be effective in reducing tumor volume or clinical stage and may even enhance pelvic control and survival. However, there are significant limitations to the use of neoadjuvant therapy in the non-responder group. They include delayed total treatment course, the presence of drug resistant clones which result in accelerated tumor growth, and limited bone marrow reserve for subsequent definitive therapy. Thus, there is a need to identify parameters providing a more precise indication of the response to neoadjuvant chemotherapy in patients with invasive cervical cancer. From Jan. 1995 to Jan. 1996, neoadjuvant chemotherapy with 3 courses of cisplatin and vincristine was used in 32 patients with invasive cervical cancer (FIGO stage Ib to IIIb; tumor size greater than 2 cm). Prior to chemotherapy, quantitative tissue levels of epidermal growth factor receptor (EGFR) and c-erbB-2 oncogene protein were measured by using an enzyme-linked immunosorbent assay (ELISA). tumor size was estimated before and after chemotherapy. Relations between oncoproteins and reductions of tumor size were evaluated. tumor size prior to neoadjuvant chemotherapy did not show any correlation with either the concentrations of EGFR or c-erbB-2 oncoprotein. As well, the tumor reduction index did not manifest any correlation with EGFR, it did had an inverse linear correlation with the c-erbB-2 oncoprotein levels (Rs = -0.71, P < 0.05). The results of this study suggest that c-erbB-2 oncoprotein is associated with a reduced response to neoadjuvant chemotherapy in primary treatment of invasive cervical cancer and may be useful in directing therapeutic approaches.

HER2 is overexpressed in about 25% to 30% of breast cancers and associated with poor prognosis, resistance to hormonotherapy and lack of sensitivity to CMF-based adjuvant chemotherapy. Herceptin (trastuzumab), a humanized monoclonal antibody, administered as a single agent, produces objective responses in phase II trials in patients with metastatic breast cancers overexpressing HER2. It has shown a substantial benefit in a phase III trial which compares a standard first line chemotherapy (doxorubicin and cyclophosphamide or taxol alone) to the same chemotherapy with Herceptin in metastatic breast cancer. The Herceptin arm had significantly higher response rate (+ 53%), an improvement in the median duration of response (+ 57%) as well as in time to progression (+ 65%) compared to chemotherapy alone.

Gastric carcinoma is one of the most common carcinomas and a leading cause of death from cancer in Turkey. The relationship between clinicopathological features of the disease and oncogenes is under investigation. In this retrospective study we investigated the relationships between expression of c-erbB-2 oncoprotein and grade, stage and pathological characteristics of the tumour, and prognosis. Formalin-fixed, paraffin-embedded tissue sections were prepared from gastrectomy specimens from 55 patients with gastric carcinoma. The tissue sections were stained immunohistochemically to reveal c-erbB-2 protein. Six (10%) of the tumours stained positively for c-erbB-2 protein. There was no statistically significant association (P > 0.5) between c-erbB-2 staining and tumour grade, stage or pathological characteristics (necrosis, lymph-node infiltration), or between staining and prognosis. The results suggest that overexpression of c-erb-B-2 protein is not related to the pathological characteristics of the tumour in gastric carcinoma and is not an important prognostic indicator.

Oncogene amplification, such as HER-2/neu (C-erbB-2), is a manifestation of genetic instability often associated with the genesis and progression of cancer, including cervical cancer. oncogene overexpression is traditionally studied using immunohistochemistry. We previously reported studies of oncogene amplification in breast cancer using fluorescent in situ hybridization (FISH), where the data support the hypothesis that HER-2/neu is a prognostic marker of poor outcome. To explore further the possible significance of HER-2/neu oncogene amplification in cervical cancer, we conducted a pilot study of 24 cervical cancer cases. The HER-2/neu FISH probe (Vysis, Inc., Downers Grove, IL) was used to measure gene amplification, with a chromosome 17 centromeric probe as an internal control. Out of 24 cases studied, 23 were informative. Of the 23 informative cases, 2 (8.7%) were found to be amplified. The rest (21 out of 23 or 91.3%) were nonamplified. Both amplified cases were invasive adenocarcinoma. Although the sample size of this pilot study may be somewhat small, the data obtained so far clearly demonstrated that detection of oncogene amplification in cervical cancer is not only feasible but is very sensitive, and suggest that further exploration using a larger sample size may be warranted.

The amplification of c-erbB-2 oncogene has been reported to have clinical relevance as a prognostic index in breast cancer. However, controversies still remain about its interpretation, mainly due to the inaccuracy of methods used for this purpose and to the unpredictable variability of the ratio between cancer and normal cells. Accurate quantitative assay, combined with strategies for selection or enrichment of tumor cell populations, could shed a new light on the relationships between molecular alterations and their clinical relevance. In this study, amplification of c-erbB-2 was measured by competitive PCR in 21 aneuploid breast cancers using a multiple DNA competitor both in whole homogenized cancer cells and in aneuploid enriched clones obtained after flow cytometry cell sorting. Most breast cancers (10/12) carrying c-erbB-2 oncogene amplification showed a significant increase in copy number in sorted aneuploid clones, and 2/9 apparently not amplified in basal samples were found to be amplified after being sorted for the aneuploid population. A general concordance between amplification and c-erbB-2 overexpression was found. The mean degree of amplification in sorted aneuploid clones is increased in breast cancers with the highest levels of c-erbB-2 protein overexpression. These data indicate that in breast cancers the amplification of c-erbB-2 oncogene is mainly associated with aneuploid cells.

The epidermal growth factor (EGF) induces the rapid formation of dendritic processes and the dissociation of SK-OV-3 ovarian cancer cells. The SK-OV-3 cell line is characterized by over-expression of the c-erbB-2 oncogene product (p185(c-erbB-2)). To investigate the role of p185(c-erbB-2) in cell motility, a c-erbB-2-specific single-chain antibody was expressed in SK-OV-3 cells using a retroviral expression vector. Eight individual clones expressing the single chain antibody were isolated. These clones have prominent retention of the cell-surface p185(c-erbB-2). The EGF-induced morphologic changes and cell motility of the single-chain-antibody-expressing clones were strongly inhibited, as observed in cell dissociation and in transmigration experiments. However, the suppression of p185(c-erbB-2) does not inhibit the motility signal elicited by 12-O-tetradecanoyl-phorbol-13-acetate. These data indicate that the c-erbB-2 oncogene product is essential to mediate the motility signal of EGF to SK-OV-3 ovarian cancer cells. The enhancement of tumor-cell motility may be partially responsible for the unfavorable prognosis of ovarian cancer with over-expression of c-erbB-2.

Morphologic examinations of mammary neoplasias arising in BALB/c (H-2d) mice carrying the activated rat HER-2/neu oncogene (BALB-NeuT), and in FVB (H-2q) mice bearing the wild-type proto-oncogene (FVB-NeuN), indicate that both conditions result in a very human-like lobular carcinoma of alveolar type, whose histotype is the result of the preferential expression of HER-2/neu products in the epithelium of lobular ducts and lobules. Detailed analysis of tumor progression indicates that transition from lobular hyperplasia to overt carcinoma is associated with a high epithelial proliferation rate, as assessed by anti-proliferating cell nuclear antigen immunostaining, and coincides with the activation and maximal extension of tumor angiogenic process as assessed by microvessel count (anti-CD31), anti-beta3 integrin, and anti-laminin immunostaining. Neovascularization is accompanied by vascular endothelial cell growth factor and basic fibroblast growth factor production by hyperplastic epithelial cells. By contrast with the BALB-NeuT tumors, E-cadherin expression is almost nonexistent in those arising in FVB-NeuN mice and this may explain their high metastatic potential. Despite their different kinetics, however, the lung metastases observed in both strains are histologically similar and resemble the primary tumor. Both strains can thus be proposed as models for "in vivo" investigation of the origin and progression of the alveolar type of lobular mammary carcinoma and the testing of new therapeutic approaches.

The presence of the c-erbB2 oncoprotein was demonstrated by immunohistochemistry in a study involving 173 mammary lesions. The lesions included infiltrating cancers, non-invasive neoplasia, as well as atypical and benign lesions. Our aim was to investigate the correlation between the c-erbB2 oncoprotein overexpression and the morphological features of the different mammary tissues analyzed to obtain a better characterization for the growth potential of certain lesions, with emphasis placed on the non-invasive neoplasia and the atypical lesions. Nearly 30% of infiltrating ductal carcinomas (27/89 cases) and 2 out of 24 infiltrating lobular carcinomas were positive. The comedocarcinomas were mostly stained (83%). In contrast, the intraductal carcinomas of cribriform or papillar patterns were consistently negative. No staining was observed in the atypical epithelial hyperplasia located in the vicinity of positive cancers for anti-oncoprotein c-erbB2 antibody. Furthermore, the only 5 positive cases for c-erbB2 out of 32 cancer-free cases were three fibroadenomas and two fibrocystic diseases with atypical ductal hyperplasia. A close correlation was thus observed between c-erbB2 oncoprotein overexpression and cancerous cell morphology, characterized by a marked nuclear hypertrophy often associated with cellular pleomorphism. However, predictive abnormalities of malignant transformation in non-neoplastic epithelial proliferation was difficult to identify, considering only the c-erbB2 expression. A group of tumors with little nuclear abnormalities were found positive for c-erbB2 immunostaining. These probably corresponded to a particular cellular phenotype. Further studies involving other oncogenes should lead to a better characterization of the different tumor phenotypes and help to clarify breast carcinogenesis.

OBJECTIVE: Gastric carcinoma can be divided into two main histological and clinical types: diffuse and intestinal. The aim of this study was to investigate the expression of neu/c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR), cathepsin D (catD), progesterone receptor (PR) and tumor-associated glycoprotein-72 (TAG-72) in gastric carcinoma of these histological types. METHOD: In this randomized, prospective study we analyzed 85 biopsy samples from patients with gastric adenocarcinoma. The control group consisted of 40 specimens from normal gastric mucosa. Neu oncoprotein and PR were determined by ELISA. CatD and TAG-72 were quantified with immunoradiometric (IRMA) methods, and EGFR were studied by radioimmunoassay (RIA). RESULTS: Neu, EGFR, catD and TAG-72 concentrations were higher in the tumoral group (p = 0.02, p = 0.00001, p = 0.002 and p = 0.007, respectively). In diffuse adenocarcinomas, catD and PR expression was increased (p = 0.01 and p = 0.04 respectively), whereas TAG-72 concentration, which correlated with neu (r = 0.57), was higher in the intestinal type (p = 0.04). No significant differences in EGFR and neu concentrations were seen between the two histological types. CONCLUSIONS: The higher PR and catD concentrations in diffuse adenocarcinomas, and the overexpression of TAG-72 in the intestinal type, support the existence of two modes of gastric carcinogenesis.

Monoclonal antibody (MAb) internalization can have a major effect on tumor retention of radiolabel. Two anti-HER-2/neu MAbs (TA1 and 520C9) were radioiodinated using the iodogen, N-succinimidyl 5-iodo-3-pyridinecarboxylate (SIPC), and tyramine-cellobiose (TCB) methods. Paired-label studies compared internalization and cellular processing of the labeled MAbs by SKOv3 9002-18 ovarian cancer cells in vitro. Intracellular radioiodine activity for 520C9 was up to 2.6 and 3.0 times higher for SIPC and TCB labeling, respectively, compared with iodogen. Likewise, intracellular activity for TA1 was up to 2.3 and 2.9 times higher with the SIPC and TCB methods compared with iodogen labeling. Unfortunately, similar advantages in tumor accumulation were not achieved in athymic mice bearing SKOv3 9008-18 ovarian cancer xenografts.

Carcinoma of the breast has an unpredictable biological behaviour. Several oncogenes have been implicated in the progression of breast cancer. Immunohistochemical staining of c-erbB-2 (Neu) oncoprotein and mutant p53 protein on 45 cases of infiltrating duct carcinoma (IDC) of the breast revealed 33% membrane positivity of c-erbB-2 oncoprotein, 46% nuclear positivity of mutated p53 protein, 33% and 84% membrane positivity of EGF-R and EMA respectively. Staining profile of c-erb-B2 oncoprotein in various histological subtypes of IDC of the breast indicated a high positivity rate in comedo followed by NOS and cibriform subtype. Similarly, high incidence of immunopositivity of mutated p53 protein was observed in comedo and cibriform subtypes while papillary carcinoma were found exclusively positive for mutated p53 protein. Interestingly, tubular subtype of IDC was not positive for c-erbB-2 oncoprotein as well as p53 mutant protein. Further, comedo and cibriform subtypes of IDC revealed high grade histological features of tumour of the breast with high mitotic count, presence of marked pleomorphism and multinucleation thus, reflecting a positive relationship with overexpression of c-erbB-2 (Neu) oncoprotein as well as mutant p53 protein. The results on immunoexpression of c-erbB-2 oncoprotein and mutated p53 protein in various histological subtypes of IDC of the breast demonstrated c-erbB-2 status as an important predictor and also indicated that oncogene product may be involved in growth factor response pathway.

We examined risk factors for breast cancer after subdividing cases based on the presence of HER-2/neu oncogene amplification in their tumors. Data were from the Carolina Breast cancer Study, a population-based, case-control study of 577 invasive breast cancer patients, diagnosed during 1993-1996 and ages 20-74 years, and 790 controls frequency-matched on race and age. Information on breast cancer risk factors was obtained from structured personal interviews. About 20% of paraffin-embedded tissues from the breast cancers of cases were identified as positive for HER-2/neu amplification (HER-2/neu+) by differential PCR. Early age at menarche, higher waist:hip ratio, and family history of breast or ovarian cancer were associated with elevated odds ratios (ORs) for both HER-2/neu+ and HER-2/neu- breast cancers. Breastfeeding for at least 1 year was inversely associated with HER-2/neu+ breast cancer [OR, 0.3; 95% confidence interval (CI), 0.1-0.7] more so than HER-2/neu- breast cancer (OR, 0.8; 95% CI, 0.5-1.2). Most of the remaining risk factors had ORs around 1.0 for both HER-2/neu+ and HER-2/neu- breast cancers, although a few exhibited possible associations with one disease subtype in analyses stratified by menopausal status. These study results suggest that most recognized breast cancer risk factors do not operate through HER-2/neu amplification in breast carcinogenesis. Differential effects of long-term breastfeeding by HER-2/neu amplification status have been observed in earlier studies and are provocative; however, the direction and magnitude of the associations have not been consistent.

Amplification and overexpression of erbB-2/neu is an important determinant in the initiation and progression of human breast cancer. Indeed, transgenic mice that over-express the neu proto-oncogene heritably develop mammary adenocarcinomas. tumorigenesis in these transgenic strains is associated with activation of the intrinsic catalytic activity of Neu. In many of these tumors, activation of Neu occurs as a result of somatic mutations located within the transgene itself. Examination of the altered neu transcripts revealed the presence of in-frame deletions that encode aberrant Neu receptors lacking 5 to 12 amino acids within the extracellular domain proximal to the transmembrane region of Neu. In addition to these deletion mutants we have also detected single point mutations within this juxta-transmembrane region. The majority of the mutations analyzed affect the one of several conserved cysteine residues present within this region. Introduction of these activating mutations into the wild-type neu cDNA results in its oncogenic conversion. Taken together, these observations suggest that this cysteine-rich region plays an important role in regulating the catalytic activity of Neu.

Measurements of either HER2 gene overexpression or its gene-coded protein (p185) are clinically useful for predicting prognosis in breast cancer. The measurements are also useful for identifying metastatic breast cancer patients who may benefit from Herceptin treatment. Since fine needle aspiration (FNA) of the breast has become an increasingly popular technique for obtaining tissue specimens, we have developed a sensitive method to quantify p185 in the aspirate. For this procedure, p185 from the cell pellet of FNA is extracted with a buffer containing Triton X-100, and the p185 is measured with an enzyme immunoassay. Most of the malignant breast tumors (N=7) in this study were associated with elevated p185 concentrations (6/7, 319+/-222 U/mg), compared to the p185 concentrations in normal breast tissue (42.8+/-35 U/mg, N=47) or benign lesions (43.1+/-20.2 U/mg, N=22). Quantification of p185 in FNA may improve the assessment of breast cancer patients, revealing whether they are at high risk and may benefit from Herceptin treatment.

In order to understand the relationship of C-erbB-2 oncogene overexpression to ER and PR in breast cancer and its prognostic significance, we examined overexpression of C-erbB-2 oncogene in 106 breast carcinomas by using immunohistochemical techniques (LSAB). The results showed that the positive rate of C-erbB-2 overexpression was 63.21% (67/106). The overexpression of C-erbB-2 oncogene related negatively with survival. 81.63% of the cases with overexpression of C-erbB-2 oncogene survived < or = 5 years and 34.29% survived > 10 years. There were significant associations of C-erbB-2 overexpression with advance clinical stage, high histological grade, and positive axillary node status in breast cancers. Negative relationship between hormone receptors and C-erbB-2 oncogene. ALL of these findings suggested that overexpression of C-erbB-2 oncogene might be an important prognostic factor and the detection of C-erbB-2 oncogene might be arranged as a regular pathological examination in the cases of breast cancer.

BACKGROUND: HER 2/new oncogene is an important prognostic marker in Breast cancer and has implications in therapy planning. OBJECTIVE: To describe the clinical features of HER 2/new positive and negative Breast cancer in the Pakistani patient population and note clinical differences between the two groups if any. DESIGN: A retrospective analysis of Breast cancer cases at the Aga Khan University, Hospital. METHOD: Immunochemical staining on formation fixed paraffin embedded tissue using oxidase antiperoxidase method. A total of 152 Breast cancer tissue samples were tested for HER-2/neu gene presence. Of these 43 (39%) samples tested positive and 109 (61%) tested negative. A comparison of the two groups revealed that only a few factors tested for either significance or borderline statistical significance between the two groups. These factors included the estrogen receptor status and the number of lymph nodes involved in the axilla. The progesterone receptor status was of borderline significance. CONCLUSION: Given the large number of factors tested it appears that there is no consistent defining feature which helps to separate HER-2/neu positive versus HER-2/neu negative cases with Breast cancer.

Overexpression of the c-erbB-2/HER-2/neu protooncogene which encodes for the tyrosine kinase receptor p185neu, has been observed frequently in cisplatin resistant human tumors, such as colorectal, breast, and non-small-cell lung cancers, and is known to induce resistance to cisplatin (CDDP) in vitro. To confirm a direct relationship between erbB-2 expression and CDDP resistance, we examined the role of erbB-2 in the cellular sensitivity to cisplatin using erbB-2 transfected HAG-1 human gallbladder adenocarcinoma cell lines. Three out of four cell lines, which stably expressed ErbB-2 protein (p185neu), did not show CDDP resistance but acquired sensitivity to cisplatin, compared to non-transfected cells. This chemosensitivity appears to be inversely correlated with the abundance of p185neu. Although the mechanism still remains unclear, these results suggest that sensitivity to CDDP in erbB-2 expressed cells may vary, depending on the cell type.

The neu (c-erbB-2, Her-2) protooncogene is amplified and overexpressed in 20-30% of human breast cancers. Although transgenic mouse models have illustrated the role of Neu in the induction of mammary tumors, Neu expression in these models is driven by a strong viral promoter of questionable relevance to the human disease. To ascertain whether expression of activated Neu under the control of the endogenous promoter in the mammary gland could induce mammary tumors we have generated mice that conditionally express activated Neu under the transcriptional control of the intact endogenous Neu promoter. expression of oncogenic neu in the mammary gland resulted in accelerated lobulo-alveolar development and formation of focal mammary tumors after a long latency period. However, expression of activated Neu under the normal transcriptional control of the endogenous promoter was not sufficient for the initiation of mammary carcinogenesis. Strikingly, ALL mammary tumors bear amplified copies (2-22 copies) of the activated neu allele relative to the wild-type allele and express highly elevated levels of neu transcript and protein. Thus, like human erbB-2-positive breast tumors, mammary tumorigenesis in this mouse model requires the amplification and commensurate elevated expression of the neu gene.

Breast cancer is one of the common cancers and is a leading cause of cancer mortality in women. The TG.NK transgenic mouse line on FVB strain background expresses the c-neu oncogene under the control of a MMTV promoter in mammary tissue and appears to be a useful animal model for evaluation of strategies to delay or prevent mammary cancer. Fiber-rich nonpurified diet (NTP-2000) and some retinoid analogues have delayed mammary cancer in the TG.NK model. Four week old hemizygous TG.NK female mice with MMTV/c-neu (erbB2) activated oncogene were fed NTP-2000 diet containing the retinoid analogue 4-hydroxyphenylretinamide (4-HPR) at 7 mmol/kg or the arotinoid Ro 40-8757 at 1.5 and 2.5 mmol/kg for 26 weeks. The 4-HPR at 7 mmol/kg diet delayed the development of palpable tumors up to 24 weeks, but by 26 weeks, the incidence markedly increased and was closer to the NTP-2000 diet control group. However, the 4-HPR diet markedly decreased the average weight of the tumors at 26 weeks with no decrease in multiplicity. The 4-HPR also caused significant increase in liver weights without an effect on body weight. Arotinoid Ro 40-8757 caused marked decrease in the number and branching of mammary ducts, and inhibited mammary tumor development with significant decrease in the incidence, multiplicity, and tumor weights compared to the NTP-2000 diet control. Arotinoid also caused a significant dose-related increase in liver weights without a significant effect on body weights. At the doses tested, the arotinoid but not 4-HPR decreased the circulating levels of IGF-1. However, there was no association between the IGF-1 levels and the size, incidence, or absence of tumors when evaluated for any treatment group or for ALL mice in the study irrespective of treatment. The oncogene erbB2 (c-neu) and the growth factor EGF expression were more prominent in the small tumors of the mice treated with arotinoid than in the larger tumors of the control group. PCNA staining was observed in areas where there was high erbB2 and EGF staining. The delay in onset of mammary tumors by the above retinoid analogues may be related to the delay in development of mammary glands.

Breast cancer is one of the common cancers and is a leading cause of cancer mortality in women. The TG.NK transgenic mouse line on FVB strain background expresses the c-neu oncogene under the control of a MMTV promoter in mammary tissue and appears to be a useful animal model for evaluation of strategies to delay or prevent mammary cancer. Fiber-rich nonpurified diet (NTP-2000) and some retinoid analogues have delayed mammary cancer in the TG.NK model. Four week old hemizygous TG.NK female mice with MMTV/c-neu (erbB2) activated oncogene were fed NTP-2000 diet containing the retinoid analogue 4-hydroxyphenylretinamide (4-HPR) at 7 mmol/kg or the arotinoid Ro 40-8757 at 1.5 and 2.5 mmol/kg for 26 weeks. The 4-HPR at 7 mmol/kg diet delayed the development of palpable tumors up to 24 weeks, but by 26 weeks, the incidence markedly increased and was closer to the NTP-2000 diet control group. However, the 4-HPR diet markedly decreased the average weight of the tumors at 26 weeks with no decrease in multiplicity. The 4-HPR also caused significant increase in liver weights without an effect on body weight. Arotinoid Ro 40-8757 caused marked decrease in the number and branching of mammary ducts, and inhibited mammary tumor development with significant decrease in the incidence, multiplicity, and tumor weights compared to the NTP-2000 diet control. Arotinoid also caused a significant dose-related increase in liver weights without a significant effect on body weights. At the doses tested, the arotinoid but not 4-HPR decreased the circulating levels of IGF-1. However, there was no association between the IGF-1 levels and the size, incidence, or absence of tumors when evaluated for any treatment group or for ALL mice in the study irrespective of treatment. The oncogene erbB2 (c-neu) and the growth factor EGF expression were more prominent in the small tumors of the mice treated with arotinoid than in the larger tumors of the control group. PCNA staining was observed in areas where there was high erbB2 and EGF staining. The delay in onset of mammary tumors by the above retinoid analogues may be related to the delay in development of mammary glands.

Overexpression and amplification of the HER-2 oncogene in patients with breast cancer has correlated with early onset of metastasis, resistance to hormonal therapy and some forms of chemotherapy, and shortened survival. Therefore, evaluation of this putative prognostic or predictive factor seems critical. Because different antibodies are used for the detection of the 185-kd HER-2 oncoprotein, we studied the sensitivity of 3 frequently used antibodies. Immunohistochemistry results were correlated with gene amplification level as assessed by fluorescence in situ hybridization. Protein overexpression was found in 17.2% and 12.5% of cases using antibodies against the external (TAB250) and internal (CB11) domains of the protein, respectively, and in 38.0% of cases using a rabbit polyclonal antibody. Fluorescence in situ hybridization was successful in ALL 160 tumors, and amplification was found in 37 tumors (23.1%). The monoclonal antibody TAB250 had the lowest misclassification rate, 9.6% (sensitivity, 67%; specificity, 97.5%).

The prognostic and predictive role of c-erbB-2 oncoprotein in human malignancies remains controversial. The pattern of expression and the biological behaviour of c-erbB-2 protein was investigated in a series of 89 locally advanced squamous carcinomas of the head and neck. Possible associations between c-erbB-2 and T,N-stage, histological grade, microvessel density and the expression of bcl-2 and p53 proteins were sought. Biopsy material had been collected prior to the initiation of treatment which consisted of platinum based induction chemotherapy or concurrent chemotherapy and radiotherapy. In ALL cases, follow-up of at least 2 years duration was available. Positive staining was seen in 27 out of 89 (30.4%) cases and was invariably cytoplasmic, exhibiting strong reactivity in more than 50% of tumour cells. Such c-erbB-2 overexpressing tumours were not associated with a response to radiotherapy and/or induction chemotherapy. Further, survival analysis did not disclose any difference in the overall or relapse free survival between c-erbB-2 positive and negative cases. Similarly, no relationship was found with T,N-stage, histological grade and bcl-2 or p53 expression. There was, however, a significant inverse association between c-erbB-2 expression and microvessel density (p = 0.0001). Interestingly, tumours with low vascular grade (VG; MS < 26) and positive c-erbB-2 expression were less frequently associated with local aggressiveness compared to c-erbB-2 negative tumours and low VG (5/27 vs. 12/18; p = 0.001), or to c-erbB-2 negative tumours and high VG (MS > 27) (5/27 vs. 19/44; p = 0.03). These differences were statistically significant but were not related to treatment response or prognosis. Nonetheless, when patients with highly angiogenic tumours were analysed for survival, irrespective of the c-erbB-2 status, they showed a poorer prognosis than those having a low microvessel density (p = 0.06 and 0.05 for overall and relapse free survival, respectively). Six out of 89 patients presented with distant metastases, five of which had tumours negative for c-erbB-2 expression. Our results seem to indicate that the pattern of c-erbB-2 expression in locally advanced inoperable head and neck cancer is exclusively cytoplasmic. c-erbB-2 reactivity is of little value in predicting survival or chemo-radiotherapeutic response. expression of genes related to angiogenesis or other invasion and migration pathways are, apparently, more important.

Overexpression of HER-2/neu (also known as c-erbB-2) proto-oncogene frequently occurs in many different types of human cancers, including ovarian carcinoma, and is known to enhance tumor metastasis and chemoresistance. Previous studies showed that inhibition of HER-2/neu expression by various agents, such as adenovirus E1A and simian virus 40 large T, can lead to suppression of tumorigenicity of HER-2/neu-overexpressing cancer cells. Here we report that T/t-common, which contains the N-terminal common domain of simian virus 40 large T and small t antigens, could specifically repress the HER-2/neu promoter. When the coding sequence of T/t-common was stably transfected into the HER-2/neu-overexpressing human ovarian carcinoma SK-OV-3 cells, the expression of HER-2/neu was dramatically reduced by the expression of T/t-common. Accordingly the tumorigenic potential of these T/t-common-expressing clones, including the ability to grow anchorage-independently and the ability to induce tumor in nu/nu mice, was also drastically suppressed. Furthermore, when T/t-common was transiently cotransfected with the activated genomic neu into NIH3T3 cells, the transforming activity of the latter was suppressed by T/t-common in soft-agarose microcolony formation assays. Taken together, these data suggest that T/t-common may act as a transformation suppressor of the HER-2/neu oncogene. oncogene (2000).

OBJECTIVE: To determine the utility of p185 oncogene in the biological characterization of transitional cell carcinoma and in the prediction of recurrence, and to analyze survival at 5 years mean follow-up. METHODS: A prospective clinical cohort study was conducted on 81 patients. Tissue specimens were obtained between November 1992 and November 1993. The study comprised two groups: nontumoral bladder tissue specimens from 20 patients (group I) and tissue specimens from 61 patients with bladder carcinoma (group II). p185 expression was determined by enzyme immunoanalysis (EIA). A statistical analysis of the results was performed. RESULTS: p185 oncoprotein levels were higher in patients with recurrence (1098.97 HNU/mg protein vs. 924.54 HNU/mg). Although higher levels of p185 were found in the patients that had died vs those who are alive, the differences were not statistically significant for overall survival or stratification by tumor grade or infiltration (p = 0.556; ns). CONCLUSIONS: Determination of p185 oncoprotein was found to be useful in the prediction of tumor recurrence at 5 years mean follow-up.

Overexpression and activation of HER-2/neu, a proto-oncogene, play a pivotal role in cancer formation. Strong expression of HER-2/neu in cancers has been associated with poor prognosis. Reduced expression of p27(Kip1), a cyclin-dependent kinase inhibitor, correlates with poor clinical outcome in many types of carcinomas. Because many cancers with the overexpression of HER-2/neu overlap with those affected by reduced p27 expression, we studied the link between HER-2/neu oncogenic signals and p27 regulation. We found that down-regulation of p27 correlates with HER-2/neu overexpression. To address the molecular mechanism of this inverse correlation, we found that reduction of p27 is caused by enhanced ubiquitin-mediated degradation, and the HER-2/Grb2/MAPK pathway is involved in the decrease of p27 stability. Also, HER-2/neu activity causes mislocation of p27 and Jun activation domain-binding protein 1 (JAB1), an exporter of p27, into the cytoplasm, thereby facilitating p27 degradation. These results reveal that HER-2/neu signals reduce p27 stability and thus present potential points for therapeutic intervention in HER-2/neu-associated cancers.

Amplification of the c-erbB2 oncogene and numerical aberrations of chromosome 17 occur in human breast carcinomas. Apocrine adenosis (AA) of the breast has been shown occasionally to have c-erbB2 overexpression and a possible premalignant potential, but little is known about cellular level genetic alterations in AA of the breast. Fluorescence in situ hybridization (FISH) is a new approach to detect these. In this study, a series of AA was studied by immunohistochemistry for c-erbB2 protein expression and by FISH using dual colour DNA probes for the c-erbB2 gene and the centromeric region of chromosome 17. Cell membrane immunostaining was seen in 10/18 (55.6%) AA cases, but unequivocal c-erbB2 gene amplification or chromosome 17 aneusomy was not seen. The results of this study suggest that c-erbB2 overexpression without amplification may occur early in breast oncogenesis. Amplification and numerical chromosome aberrations may occur later in the pathogenesis of apocrine-derived breast carcinomas.

Paraffin-embedded tissue slides from 88 infiltrating ductal breast carcinoma were examined by immunohistochemistry technique with the use of monoclonal antibody against human p65 antigen and polyclonal antibody against p65-like protein present in fetal bovine serum. Immunohistochemical analysis of expression of growth factor receptors (EGFR), protein product of oncogene c-erb B2 as well as protein product of mutated anti-oncogene p53 was also done. It was established that there is no correlation between p65 and c-erbB2, EGFR or p53 expression. In low differentiated tumors (grade III) high p53 index and high EGFR and c-erbB2 expression was connected with low p65 expression. The lack of c-erbB2 and EGFR and low p53 expression was combined usually with high p65 oncoprotein levels.

Research tools which improve mutation detection, SNP discovery, and allele characterization will facilitate studies of cancer, inherited disease, and genomic evolution. Denaturing High-Performance Liquid Chromatography (DHPLC) is a recently developed methodology for detection of heteroduplexes formed in DNA samples containing mismatches between wild type and mutant strands. In an effort to develop a rapid, sensitive mutation detection method for studies of families with inherited kidney cancer, we evaluated DHPLC for detection and analysis of MET proto-oncogene mutations in papillary renal carcinomas (PRC). We found DHPLC to be 100% accurate in detecting 15 known disease-associated MET mutations. Significantly, each MET mutation and two novel SNPs generated a characteristic chromatographic profile or signature with reproducible distinguishing features. Standardization of DHPLC reagents and improved methods design were critical to the reliability and accuracy of mutation prediction. Improvements included addition of a 75% acetonitrile wash followed by a rejuvenating gradient, and detailed analysis of signature shape, retention time (RT), RT differences (DeltaRT), and temperature-dependent (melt) profiling. We used signatures to predict mutations in new PRC samples, mutation carriers in asymptomatic hereditary PRC family members, and in a blind study of previously characterized DNAs. Application to SNP discovery is discussed. Wiley-Liss, Inc.

One hundred and twelve infiltrating ductal carcinoma of breast were studied by the standard avidinbiotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, using a monoclonal antibody to c-erbB-2 oncoprotein. The same tumours were assessed and scored according to the Bloom and Richardson criteria into three histological grades. The distribution of tumours according to grade were: 8 Grade I, 34 Grade II and 70 Grade III. Forty-three (38.4%) tumours showed positive membrane staining for c-erbB-2 oncoprotein. These comprised 7 Grade II and 36 Grade III tumours with c-erbB-2 immunopositivity rates of 20.6% and 51.4% respectively. The oncoprotein was not expressed by Grade I tumours. This study shows a good correlation between c-erbB-2 expression and histological grade, a known prognostic indicator of invasive breast carcinoma. Because the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor gene, its overexpression can be expected to result in more aggressive tumour behaviour. While it may be regarded as another indicator of poor prognosis breast cancers, its value in the selection of carcinomas less responsive to hormonal therapy and those more suitable for immunotherapy than chemotherapy has been mooted but remains to be clarified.

Eighty-six infiltrating ductal carcinoma of breast were studied by the standard avidin-biotin complex immunoperoxidase method on formalin-fixed, paraffin-embedded tissue sections, for oestrogen receptor (ER) protein and c-erbB-2 oncoprotein expression. They were categorized according to the modified Bloom and Richardson criteria into three histological grades. 21% tumours were ER positive while 44% were c-erbB-2 positive. Of ER positive tumours, 33.3% were c-erbB-2 positive whereas the c-erbB-2 positivity rate was much higher (47.1%) in ER negative tumours. Only 16% of c-erbB-2 positive tumours were ER positive while 25% of c-erbB-2 negative tumours were ER positive. This negative relationship between ER and c-erbB-2 expression was statistically significant (Mc Nemar s test, p < 0.005). The ER positivity rate did not vary significantly with histological grade. However, c-erbB-2 overexpression was significantly more prevalent in grade III tumours compared with grade I and II tumours (Chi-square test, p < 0.005). Since the c-erbB-2 oncogene has extensive structural homology to the epidermal growth factor receptor (EGFR) gene, we expect that c-erbB-2 oncoprotein would share functional similarities with EGFR leading to both loss of oestrogen receptor and poor prognosis in breast cancer. Its overexpression can be expected to relate to more aggressive tumour proliferation and may explain its correlation with high histological grade, a known indicator of aggressive cancer behaviour. As there is no indication that ER protein activity contributes to advancement in histological grade, it would appear that cellular dedifferentiation precedes ER loss during malignant transformation. It has been mooted that ER positive breast cancers which also show c-erbB-2 oncoprotein overexpression have a poorer response to hormonal therapy. The use of this parameter in the routine assessment of breast cancer patients may identify subsets of patients for more aggressive therapy.

AIM: To evaluate the clinical usefulness of three commercially available assays for Her-2/neu oncogene and protein measurements. The Her-2/neu protein is overexpressed, mostly as a result of gene amplification, in 20-30% of human breast cancers, and has been shown to have prognostic and predictive value for treatment with chemotherapy or the new monoclonal antibody, Herceptin. METHODS: An immunohistochemistry (IHC) assay using the Dako polyclonal antibody A0485, which measures the Her-2/neu protein, was compared with two new Food and Drug Administration (FDA) approved fluorescence in situ hybridisation (FISH) assays--INFORM and PathVysion, in a cohort of 52 formalin fixed, paraffin wax embedded breast tissues. These tissues were selected randomly from 84 consecutive infiltrating breast cancer specimens, which were first stratified according to the Her-2/neu protein levels as measured by IHC. RESULTS: The two FISH assays achieved a 98% concordance rate: 14 specimens (27%) showed Her-2/neu gene amplification and 37 specimens (71%) showed no Her-2/neu gene amplification. The PathVysion assay had certain advantages over the INFORM assay. In contrast, the IHC assay detected Her-2/neu overexpression in a high percentage of cases, including 13 high positive specimens (25%) and 13 medium positive specimens (25%). Although 10 of these 13 IHC high positive specimens showed gene amplification by FISH, nine of 13 IHC medium positive specimens showed no gene amplification. Statistical analyses showed that the differences between IHC and FISH assays were primarily in the specimens with medium positive IHC, but negative FISH results. CONCLUSIONS: Because of the increasing importance of the Her-2/neu oncogene and oncoprotein in the clinical management of patients with breast cancer, the accurate and consistent evaluation of Her-2/neu status is crucial. This study suggests that the best approach is to combine both IHC and FISH assays; that is, to use the IHC assay as a triage step, followed by the PathVysion FISH assay to analyse the IHC medium and high positive cases.

This study is to evaluate the correlation of some established prognostic factors, hormone receptor and C-erbB-2 expression of breast cancer patients in Yogyakarta, Indonesia. Beginning January 1997, 60 breast cancer patients who were treated either by mastectomy, breast conserving surgery or biopsy, were evaluated clinically in connection with age, menopausal status, stage, tumor size, nodes; also histologically regarding type, grade and mitotic index. Patients were evaluated for estrogen and progesterone receptor, as well as C-erbB-2 expression with immunohistochemical techniques. Median age was 47.5 years old, range from 28 to 80 years old. Most of them were premenopause (65.0%). One patient (1.7%) was a man. Most of the patients were stage IIB (25.0%), 51.7% with positive estrogen receptor and 65.9% with positive progesterone receptor. The type was mostly invasive duct carcinoma, high grade (70.0%). Most of the tumor size ranged between 2-5 cm (56.9%), with more than 3 nodes in 38.3% of patients. High mitotic index was found in 69.5% and positive C-erbB-2 in 71.7% patients. Correlation of C-erbB-2 and other prognostic factors showed that only stage, node and mitotic index had significant correlations (p = 0.016; 0.035 and 0.005, respectively). A significant correlation was also found between ER and PR level, PR and tumor size, stage and tumor size, stage and nodes, tumor size and nodes (p < 0.05), and a borderline correlation between ER and tumor size (p = 0.065) in conclusion, this preliminary study showed that breast cancer in Yogyakarta had an aggressive phenotype. C-erbB-2 positivity was correlated significantly with stage of the disease, number of nodes involved and mitotic index. Hormone receptors also correlated with some prognostic factors in breast cancer patients.

The ice nucleation protein (INP) is a glycosyl phosphatidylinositol anchored outer membrane protein found in certain Gram-negative bacteria. In this study, the INP from Pseudomonas syringae was applied as a fusion partner with the single chain antibody fragment (ScFv) against the human oncoprotein c-myc. Two new plasmids pNinaZ-myc and pNinaZScFv-BsaA1 were constructed and cloned into Escherichia coli JM109. The expression of the fusion protein was successfully demonstrated in the cloned cells. The fusion proteins had no effect on the viability of the host cells. Ice nucleation activity measurements and flow cytometry studies were followed to investigate the membrane expression of the fusion protein.

The aim of this study was to evaluate, by means of an immunoenzymatic assay, the membranous and cytosolic c-erbB-2 oncoprotein contents in primary tumors and in adjacent mucosa from gastric cancer patients. Fifty-two patients with primary gastric adenocarcinomas were enrolled in this prospective study. c-erbB-2 protein levels were significantly higher in membranous than in cytosolic samples, both in neoplastic tissues (median: 3602 vs 525 NHU/mg protein; p<0.0001) and in adjacent mucosa samples (median: 3174 vs 509 NHU/mg protein; p<0.0001). Nevertheless, there was a significant positive relation between membranous and cytosolic c-erbB-2 protein contents in both neoplastic tissue (p<0.001) and adjacent mucosa (p<0.001) samples. There was no significant difference in the membranous c-erbB-2 protein content between neoplastic tissues and adjacent mucosa samples. However, the cytosolic c-erbB-2 content was significantly higher in neoplastic tissues than in adjacent mucosa (p<0.05). Finally, the results did not show any significant correlations of these oncoprotein contents with patient characteristics, clinicopathologic parameters and overall survival of the study population.

OBJECTIVE: To examine the relationship between oncoprotein c-erbB2 over-expression and prognosis of primary breast tumor patients, and find if it can be used as a prognostic indicator. METHODS: Eighty-five cases of paraffin-embedded specimens were used for immunohistochemical study. RESULTS: Over-expression of c-erbB2 was observed in none of the 7 benign breast tumors. Twenty-three out of 78 cases of breast cancer showed over-expression with a positive rate of 29.4%. Over-expressed c-erbB2 oncoprotein was not detected in 80% of patients with negative lymph node. In clinical stage III patients, 71% of them over-expressed c-erbB2. The expression of c-erbB2 and estrogen receptor(ER) was inversely correlated in 67% of breast cancer patients. oncoprotein c-erbB2 over-expression had no correlation with lymph node status(P > 0.05), but was closely correlated to clinical staging(P < 0.05). CONCLUSION: Patients with over-expression of c-erbB2 oncoprotein showed poor prognosis. The c-erbB2 may be used for predicting the prognosis of breast cancer patients.

Ocular sebaceous carcinoma (OSC) is an uncommon malignancy with a potential to recur and metastasize. Some characteristics of sebaceous carcinoma, such as female preponderance, shown in the present series during 11-year period at Korea cancer Center Hospital, led us to study their hormone receptors and c-erbB-2 expression. c-erbB-2 overexpression was very common (83%) in OSC, and was not associated with pathologic findings or clinical outcome. Interestingly, estrogen and progesterone receptor was detected in 4 and 2 cases, respectively, suggesting a role of hormonal influence on this neoplasm. Immunohistochemical and clinicopathologic features of 18 cases of OSC in Korea are presented.

Immunomodulatory strategies, such as antibody therapy and cancer vaccines, are increasingly being considered as potential adjuvant therapies in patients with advanced stage breast cancer to either treat minimal residual disease or prevent relapse. However, little is known concerning the incidence and magnitude of the pre-existent breast cancer specific immune response in this patient population. Using the HER-2/neu oncogenic protein as a model, a well-defined tumor antigen in breast cancer, we questioned whether patients with advanced stage HER-2/neu overexpressing breast and ovarian cancers (III/IV) had evidence of pre-existent immunity to HER-2/neu. Forty-five patients with stage III or IV HER-2/neu overexpressing breast or ovarian cancer were evaluated for HER-2/neu specific T cell and antibody immunity. Patients enrolled had not received immunosuppressive chemotherapy for at least 30 days (median 5 months, range 1-75 months). ALL patients were documented to be immune competent prior to entry by DTH testing using a skin test anergy battery. Five of 45 patients (11%) were found to have a significant HER-2/neu specific T cell response as defined by a stimulation index > or = 2.0 (range 2.0-7.9). None of eight patients who were HLA-A2 had a detectable IFNgamma secreting T-cell precursor frequency to a well-defined HER-2/neu HLA-A2 T cell epitope, p369-377. Three of 45 patients (7%) had detectable HER-2/neu specific IgG antibodies, range 1.2-8.9 microg/ml. These findings suggest that patients with advanced stage HER-2/neu overexpressing breast and ovarian cancer can mount a T cell and/or antibody immune response to their tumor. However, in the case of the HER-2/neu antigen, the pre-existent tumor specific immune response is found only in a minority of patients.

Determination of HER-2/neu oncogene amplification has become necessary for selection of breast cancer patients for trastuzumab (Herceptin) therapy. Fluorescence in situ hybridization (FISH) is currently regarded as a gold standard method for detecting HER-2/neu amplification, but it is not very practical for routine histopathological laboratories. We evaluated a new modification of in situ hybridization, the chromogenic in situ hybridization (CISH), which enables detection of HER-2/neu gene copies with conventional peroxidase reaction. Archival formalin-fixed paraffin-embedded tumor tissue sections were pretreated (by heating in a microwave oven and using enzyme digestion) and hybridized with a digoxigenin-labeled DNA probe. The probe was detected with anti-digoxigenin fluorescein, anti-fluorescein peroxidase, and diaminobenzidine. Gene copies visualized by CISH could be easily distinguished with a x40 objective in hematoxylin-stained tissue sections. HER-2/neu amplification typically appeared as large peroxidase-positive intranuclear gene copy clusters. CISH and FISH (according to Vysis, made from frozen pulverized tumor samples) correlated well in a series of 157 breast cancers (kappa coefficient, 0.81). The few different classifications were mostly because of low-level amplifications by FISH that were negative by CISH and immunohistochemistry with monoclonal antibody CB-11. We conclude that CISH, using conventional bright-field microscopy in evaluation, is a useful alternative for determination of HER-2/neu amplification in paraffin-embedded tumor samples, especially for confirming the immunohistochemical staining results.

The c-erbB-2 proto-oncogene encodes a transmembrane protein tyrosine kinase receptor of 185 kDa (p185) and has been associated with several types of human cancers. In human breast cancer, overexpression of p185 occurs in 15-30% of cases, correlates with poor prognostic factors and characterizes breast cancers with a more aggressive behavior. Overexpression of p185 is usually associated with c-erbB-2 amplification, though it may occur independently and thus define subpopulations of breast cancers which might be of clinical interest. p185 expression is usually detected by immunohistochemistry (IHC) and few studies have been carried out to evaluate the p185 content of breast cancers with an ELISA technique. In this context, we showed, in 106 breast cancer samples, that p185 was expressed at high levels in 13.2%, intermediate levels in 55.7% and negative ones in 31.1% of cases. ALL p185 positive samples showed a c-erbB-2 oncogene amplification while none of the p185 negative samples and only 4% of p185 imtermediate samples had an amplification of c-erbB-2. p185 expression is significantly correlated with the negativity of estrogen and progestrone receptors, with high levels of cathepsin D and in some conditions with axillary nodal involvement. Thus, using the p185 ELISA assay, the c-erbB-2 status of breast cancers can be defined and moreover a subset can be discriminated which is characterized by intermediate levels of p185 and absence of c-erbB-2 amplification. The quantitative approach towards p185 in breast cancers affords the possibility of identifying more appropriately patients with high or low risk and thus permits adaptation of therapeutic regimens.

Previous studies of molecular prognostic markers following resection for exocrine pancreatic cancer have produced conflicting results. Our aim was to undertake a comprehensive analysis of potentially useful molecular markers in a large, multicentre patient population and to compare these markers with standard pathological prognostic variables. Formalin-fixed, paraffin-embedded specimens of pancreatic ductal adenocarcinoma were analysed from 157 patients [100 men and 57 women with a median (range) age of 60 (33-77) years] who had undergone pancreatectomy. Immunohistochemistry was used to detect expression of p16(INK4), p53, p21(WAF1), cyclin D1, erbB-2 and erbB-3. mutations in codons 12 and 13 of the K-ras oncogene were detected by SSCP and sequencing following DNA extraction and amplification by PCR. The median (range) survival post-resection was 12.5 (3-83) months. Abnormalities of p16(INK4), p53, p21(WAF1), cyclin D1, erbB-2 and erbB-3 expression were found in 87%, 41%, 75%, 72%, 33% and 57% of cases, respectively. There was no significant correlation between expression of any of these markers and patient survival. K-ras mutations were found in 73 (75%) of 97 cases with amplifiable DNA. The presence of K-ras mutation alone did not correlate with survival, but there were significant differences in survival according to the type of K-ras mutation (p = 0.0007). Reduced survival was found in patients with GaT, cGT and GcT K-ras mutations compared to GtT, aGT and GaC mutations. In conclusion, survival was associated with type of K-ras mutation but not expression of p16(INK4), p53, p21(WAF1), cyclin D1, erbB-2 and erbB-3.

The proto-oncogene products erbB-l (EGF-Receptor) and erbB-2 (HER-2/neu), distinct members of the epidermal growth factor receptor family, are frequently overexpressed in squamous cell carcinoma of the head and neck (SCCHN). The accumulation of these transmembrane proteins may lead to significant amounts of the respective extracellular receptor domains (ECD) that are shed from the tumour cell surface and enter blood circulation, thus representing potential serum tumour markers. For erbB-l and erbB-2, we determined the ECD serum levels with enzyme-linked immunosorbent assays and evaluated the protein expression in tumour tissue by immunohistochemistry. The present study included 49 patients (37 untreated, 12 recurrences) and the same number of age- and sex-matched healthy controls. In 24 patients ECD serum levels were determined before and 6 weeks after surgery. Mean ECD serum levels for erbB-1 and erbB-2 were 54.8+/-1.6 and 153.7+/-6.1 fmol/ml in cancer patients, and 54+/-1.5 and 147.9+/-4.5 fmol/ml in healthy controls, respectively. There was no significant difference between untreated and recurrent disease. Serum ECD follow-ups 6 weeks after surgery revealed a significant 12.3% decline of erbB-1 but no change of erbB-2 values. Immunohistochemistry showed strong staining for erbB-1 in 78% and erbB-2 in 47% of the SCCHN specimens. No correlation was detectable between receptor ECD serum levels and receptor tissue expression, tumour stage, and tumour differentiation. Hence, ECD serum levels of erbB-1 and erbB-2 are not considered to be valuable tumour markers in SCCHN.

The peroxidase-antiperoxidase (PAP) method was used for localization of the c-erbB-2 oncoprotein at the electron microscopical level in 15 patients with laryngeal squamous cell carcinoma. It was found that c-erbB-2 oncoprotein was present in 7 of 15 samples. Electron microscopical examination revealed expression of the c-erbB-2 oncoprotein both on the membrane of individual cells and in the cytoplasm. In 5 of the 7 cases of positive labeling, it was observed only on the plasma membrane of cells whereas in 2 cases, there was also cytoplasmic staining. Reaction product was associated with endoplasmic reticulum, and the nuclear envelope and was scattered throughout the cytoplasm on ribosomes. Control incubations using normal rabbit serum instead of the primary antibody showed no labeling. A significant correlation between c-erbB-2 oncoprotein and pathological characteristics such as nodal status and histological grade was not found.

Breast cancer is one of the most common cancers and is a leading cause of mortality in women. The TG.NK transgenic mouse line expresses the c-neu breast cancer oncogene under the control of a MMTV promoter and appears to be a useful animal model for evaluation of intervention strategies to delay/prevent breast cancer. Fiber-rich nonpurified diet (NTP-2000) and some retinoid analogues have been shown to significantly delay the development of mammary cancer in the TG.NK model. Four-week-old hemizygous TG.NK female mice with MMTV/c-neu oncogene fed NTP-2000 diet were gavaged with 0.05-0.2 ml of flaxseed oil as the source of omega-3 rich PUFA, or melatonin at 50-200 mg/kg or a combination of 0.10 ml flaxseed oil and 50 mg/kg melatonin in a gavage volume of 0.2 ml per mouse with corn oil as the vehicle for 30 weeks. The time course of the mammary tumor incidence pattern was advanced by flaxseed oil compared to the control. At the high dose (0.2 ml) of flaxseed oil, when the omega-6: omega-3 PUFA ratio was closer to 1, there was some delay in the growth of mammary tumors. Melatonin delayed the appearance of palpable tumors and the growth of the tumors with a dose-related statistically significant negative trend for the incidence of tumors. The combination of flaxseed oil and melatonin caused a significant decrease in the number of tumors and tumor weight per mouse compared to the control and to flaxseed oil but not to melatonin alone. Flaxseed oil may delay the growth of mammary tumors if the omega-6:omega-3 PUFA ratio of fat consumed is closer to 1. Melatonin has the potential to markedly delay the appearance of palpable mammary tumors. Studies are in progress with the TG.NK mouse model to understand the histological and molecular changes associated with the dose-response pattern of mammary tumor incidence and growth after treatment with a broad range of doses of melatonin.

Some node-negative breast cancer patients, with initially good prognosis, relapse from their cancer and are poorly identified. In the present study, based on prospective data of 197 tumors, we measured cathepsin D (cath D, n=197), pS2 protein (n=125), c-erbB-2 oncoprotein (n=100) and epidermal growth factor receptor (EGF-R, n=99) to better define the risk of relapse of node-negative patients in comparison with that defined by the clinical and histological factors. The median follow-up in surviving patients was 75 months. Univariate analysis indicated that patients with histological grade III tumors (the Scarff, Bloom and Richardson classification) had a much poorer prognosis than those with histological grade I or II tumors (P=0.0027 for relapse-free survival and P=0.0156 for overall survival). When the population of node-negative patients was divided by tertiles, high cath D levels showed a significant association with an early relapse (P=0.0316). Using cut-off values, patients with high cath D (> or =25 pmol/mg protein) or c-erbB-2 oncoprotein (> or =4 Human Neu Unit/microg protein) levels, had a significant worse relapse-free survival (P=0.0147 and 0.0417, respectively). No prognostic information was supported by pS2 protein or EGF-R measurements. In multivariate analysis, histological grade, cath D and c-erbB-2 oncoprotein remained independent predictors of recurrence (P=0.005, 0.0361 and 0.0321, respectively). By combining low levels of cath D and c-erbB-2 oncoprotein in histological grade I or II tumors, we identified a subgroup of patients with a 100% relapse-free survival probability at 6 years of follow-up. Moreover, the subgroup of patients with histological grade I or II tumors and high values of both cath D and c-erbB-2 oncoprotein showed a prognosis as poor as the subgroup defined by histological grade III alone, respectively 66% and 70% relapse-free survival at 6 years of follow-up. In conclusion, the combination of conventional prognostic factor (histological grade) and biochemical factors (cath D and c-erbB-2 oncoprotein) enabled us to identify, in this preliminary study, a subgroup of patients having an increased risk of relapse in a group (node-negative patients with low histological grade tumors) considered as good prognosis.

BACKGROUND: Overexpression of the ErbB-2 (HER2/neu) receptor tyrosine kinase is one of the most common molecular changes in human cancer, but the functional significance of this phenotype remains uncertain. METHODS AND RESULTS: Using phosphorylation-specific antibodies recognizing different ErbB-2 functional states, we assessed the phosphorylation status of ErbB-2 in 102 human breast cancer specimens. Quantitative ErbB-2 immunoblotting intensity correlated directly with that of immunohistochemistry (r = 0.84). Widely varying phosphorylation profiles were evident in 65 ErbB-2-positive carcinomas, suggesting different ErbB-2 functions in different tumors. In a subset of patients for whom clinical data were obtainable, mortality trends were strongly associated with the quantitative signal intensities of ErbB-2 phosphoantibodies (P < or =.02), but not with those of conventional antibodies to ErbB-2 (P = .147), epidermal growth factor receptor (P = .44), or phosphotyrosine (P = .94). CONCLUSION: Although requiring corroboration in larger prospective clinical studies, these findings suggest that immunophenotyping using phosphorylation-specific antibodies may enable more accurate prediction of cancer behavior than is currently obtainable using conventional reagents.

Three Myb-related genes (A-Myb, B-Myb, and c- Myb) have been found in ALL vertebrates examined thus far including mammals, birds, and amphibians. Two invertebrates, the sea urchin and the fruit fly, have only one Myb-related gene. Our laboratory has used Drosophila as a model system to explore the function of its sole Myb gene. We have also reintroduced the three different vertebrate Myb genes into Drosophila in order to begin to understand how their different functions may have arisen following gene duplication during evolution.

tumor tissue from patients with advanced breast cancer was analyzed for HER-2/neu and p53 expression. The tissue samples from primary tumor and from axillary lymph nodes or distant metastases from 118 breast cancer patients were obtained. Sections from formalin-fixed, paraffin-embedded materials were immunostained for HER-2/neu and p53 oncoprotein expression. Staining results were correlated with survival times and disease-free survival times, flow cytometric synthesis phase fractions, and DNA ploidy. No correlation could be found between HER-2/neu and p53 or any other tested factor, but grade I primary cancers that were positive for HER-2/neu showed a tendency for better outcome. The HER-2/neu staining of the metastases was independent of the staining of the primary tumor. HER-2/neu can be used as a prognostic marker for advanced breast cancer, when the primary tumor is well differentiated.

It is customary to submit only one portion of a breast cancer to determine if there is amplification or overexpression of the proto-oncogene HER-2/neu. In routine studies of the expression of neu in breast cancer, however, we noted discrepancies in intratumoral positivity. To investigate this phenomenon further, multiple tumor specimens (129 samples) from 41 women with breast cancer were examined. Forty cases were analyzed for neu amplification by slot blot assay and 18 with fluorescent in situ hybridization. Neu overexpression was determined using four different specific antibodies. In more than 50% of cases there were discrepancies in results between the tissue blocks examined. This was evident in both inter- and intra-assay comparisons. It is concluded that intratumoral heterogeneity of neu amplification/overexpression in breast cancer exists to a far greater degree than previously recognized and could be a responsible factor for conflicting published data regarding neu s prognostic significance. Examination of only one tumor sample may not give a true indication of either amplification or overexpression of this oncogene.

PURPOSE: To investigate the predictive value of c-erbB-2 oncoprotein expression as compared with established histopathological and cytometric indicators of disease evolution in breast carcinoma. PATIENTS AND METHODS: A short-term retrospective study was conducted on a series of 306 breast cancer patients. Classic prognostic factors included tumour size, nodal involvement, histological grading, and hormone receptor status. Flow cytometric DNA ploidy and S-phase fraction (SPF) were also assessed. A Cox proportional hazards regression model was used for multivariate statistical analysis. RESULTS: c-erbB-2 overexpression was present in 43 out of 295 (14.6%) tumours, and showed a statistically significant correlation with high histological grade, DNA aneuploidy, high SPF and lack of estrogen receptors (ER). Univariate analysis revealed its association with worse disease-free survival (DFS) and overall survival (OS). The combined evaluation of c-erbB-2 with ploidy and SPF defines a variable (P + S + c) that showed a significant correlation with disease outcome. By multivariate analysis, only nodal status (P < 0.001) and P + S + c subgrouping (group 2: P = 0.002; group 3: P = 0.001) in relation to DFS, and nodal status (P = 0.001) and DNA ploidy (P = 0.006) in relation to OS, retained independent prognostic significance. Subset analyses showed that cytometric parameters, P + S + c subgrouping and hormone receptors were significantly correlated with disease outcome in node-positive patients, whereas in node-negative subgroup no prognostic indicators were found. c-erbB-2 overexpression exhibited a trend in node-positive breast cancer (DFS: P = 0.068; OS: P = 0.086), and significant correlation with poor clinical evolution in ER positive patients (DFS: P = 0.015; OS: P = 0.004), mostly receiving tamoxifen. CONCLUSIONS: c-erbB-2 is an independent prognostic indicator of DFS when evaluated in conjunction with ploidy and SPE. It also seems to predict response to tamoxifen therapy, by identifying a subgroup of ER positive (ER+) breast cancer patients with poor prognosis.

The HER-2/neu proto-oncogene amplification or oncoprotein overexpression is an important prognostic factor and a predictive factor for resistance to endocrine therapy and adjuvant chemotherapy in breast cancers. Moreover, it is an entry criterion in the assessment of patients for whom Herceptin (Trastuzumab) treatment is considered. The overexpression rate of HER-2/neu oncoprotein has been identified in 10% to 40% of human breast cancers. In Taiwan, a higher grade of pathobiologic characteristics of familial breast cancer was also noted than that found in the non-familial group. It is worthwhile to evaluate whether the overexpression is more frequent in familial breast cancers. Fifty-six familial and 111 non-familial breast cancers were studied between 1990 and 1999 to assess both the overexpression of HER-2/neu oncoprotein immunohistochemically and the correlation with the histological type, grade and stage of breast carcinoma. The overexpression rate is higher in the familial breast cancer group (50.0%) when compared with non-familial breast cancer group (36.9%), which did not prove to be statistically significant (P = 0.1068). However, when the infiltrating ductal carcinomas of both groups are compared, it is statistically significant (52.3% vs. 33.7%, P = 0.0429). Overexpression correlated with node status and histological grade of infiltrating ductal carcinomas in non-familial and overall breast cancers. It also correlated with nuclear pleomorphism and mitotic counts, but not tubule formation or tumor size. ALL 3 cases of Paget s disease revealed overexpression, whereas ALL 12 cases of mucinous and one case of metaplastic carcinoma and one case of medullary carcinoma were negative. The overexpression rate was higher both in familial and non-familial intraductal carcinomas (57.1% vs. 73.3%, P = 0.4716). No statistical difference was identified between the 2 subsets. A case of infiltrating ductal carcinoma combined with intraductal carcinoma revealed heterogeneous staining in the component of ductal carcinoma in situ, while the invasive component did not. This suggests that overexpression decreases within individual tumors as they evolve from in situ to invasive lesioins. The HER-2/neu may imply a different role in intraductal carcinoma, Paget s disease and invasive duct carcinoma. Although the overexpression rate of HER-2/neu oncoprotein of familial breast cancer was not significantly higher than that of the non-familial group, it is appropriate to evaluate the rate of HER-2/neu overexpression according to the histological type of breast cancers from familial breast cancer and non-familial breast cancer. The prognoses will be needed for future evaluation.

The HER-2/neu oncogene is localized to chromosome 17q and shares significant homology with the epidermal growth factor receptor. As a result of its potential role in the selection of therapy, HER-2/neu testing has reached near-standard-of-practice status in breast cancer. There is considerable interest in HER-2/neu as a prognostic factor and target of therapy in tumors of the gastrointestinal tract. In this review of HER-2/neu expression in esophageal squamous cell carcinoma and adenocarcinomas of the esophagus, stomach, and colon, a wide range of expression of HER-2/neu from 0 to 83% likely reflects both differences in methods and reagents, as well as study bias associated with patient selection (i.e., early versus advanced disease). For esophageal squamous cell carcinoma, little information exists as to the prognostic significance of HER-2/neu expression. In adenocarcinoma associated with Barrett s esophagus there is contradictory data. However, most of the information available indicates that this marker has significant prognostic value. In gastric adenocarcinoma, the wide expression range may truly reflect patient selection because HER-2/neu positivity appears linked to advanced rather than early disease with limited invasion. The majority of studies favor a significant prognostic value of HER-2/neu status for this tumor. Finally, in colorectal cancer HER-2/neu overexpression also appears to be a significant adverse outcome indicator as judged by the current published literature. In conclusion, given that either HER-2/neu protein overexpression or gene amplification is associated with approximately one-fourth of ALL gastrointestinal tract malignancies, strategies designed to employ the marker in therapy selection appear warranted. During the next several years it will not be surprising to see these tumors treated with antiHER-2/neu modalities such as Herceptin, likely in combination with other agents initially for patients with advanced disease, and possibly for individuals with high-risk lesions in an adjuvant setting.

Tissues from 50 cases of squamous cell carcinoma of the uterine cervix were analysed for immunohistochemical expression of c-erbB-2 oncoprotein and the patients were followed-up for 2 years. Immunopositivity of c-erbB-2 was studied with reference to clinical stage, histopathological differentiation and response to the cancer therapy. expression of c-erbB-2 protein was found to be higher (37.5%) in cases with stage II disease, whereas more expressions were noticed in poorly differentiated squamous cell carcinoma (33.3%). Among cases who showed complete response to the treatment, 20.8% were positive for c-erbB-2 oncoprotein. On the contrary, 36.8% of prognostically unfavourable cases revealed positivity for c-erbB-2 immunostaining. However, the difference between c-erbB-2 expressions of these two said groups of patients, which were divided in accordance with the response to treatment, did not attain to statistical significance. Study on c-erbB-2 among larger number of patients with cervical carcinoma may prove to be an important factor in response to cancer therapy.

PURPOSE: To evaluate the relationship between HER-2/neu overexpression and standard as well as investigational prognostic factors in Greek females with invasive breast carcinoma. MATERIALS AND METHODS: Paraffin-embedded tumor sections from 128 consecutive primary breast cancer patients were screened for HER-2/neu oncoprotein (p185) overexpression by immunohistochemistry using the polyclonal antibody A 0485. The relationship between HER-2/neu staining and other established markers of prognosis were examined using both a univariate and a multivariate analysis. RESULTS: HER-2/neu overexpression was detected in 46.1% of tumors. No statistical correlation was found between HER-2/neu and age, tumor diameter, histologic type, nodal status, tumor grade, stage, estrogen and progesterone receptor status or cathepsin-D. A significant correlation was noted between HER-2/neu and p53 overexpression in the total sample (p=0.014) as well as in node-positive patients (p=0.026). In those groups, HER-2/neu and p53 co-expression was found in 19.5% and 21.6% of cases, respectively. In node-negative patients, HER-2/neu overexpression did not correlate with any other marker. CONCLUSION: HER-2/neu overexpression seemed to correlate only with p53 oncoprotein.

BACKGROUND: Recent reports have described overexpression of p185(c-erbB2), the product of the HER-2/neu oncogene, in more than 40% of archival osteosarcomas that were examined by immunohistochemistry (IHC). However, IHC can be influenced by the method of fixation, extent of antigen retrieval, specificity and sensitivity of the antibody clone, and the use of an arbitrary semiquantitative scoring system. In contrast, fluorescence in situ hybridization (FISH) assays that assess HER-2/neu gene copy numbers in individual cells are more consistent, more reproducible, and less subjective than IHC. METHODS: The authors examined pretreatment nondecalcified archival tissue from 21 high-grade pediatric osteosarcomas for amplification of the HER-2/neu oncogene using an Food and Drug Administration (FDA)-approved FISH assay (PathVysion, Vysis Inc., Downers Grove, IL). Additionally, IHC for p185(c-erbB2) was performed in ALL cases using the Dako polyclonal antibody clone A0485 (Dako Co., Carpinteria, CA). RESULTS: None of the 21 osteosarcomas had evidence of HER-2/neu gene amplification by FISH, whereas p185(c-erbB2) IHC was negative in ALL cases. CONCLUSIONS: HER-2/neu gene amplification appeared to be an uncommon event in pediatric osteosarcomas. The reason(s) for discordance between previous IHC data and the current FISH and IHC results was unknown, but might reflect intrinsic variations in antibody clones, or might suggest that, in some cases, the occurrence of protein overexpression is independent of gene amplification.

The aim of this study was to detect activated c-K-ras by gene point mutation and to find c-erbB-2 gene amplification with p185 expression in association with the c-K-ras gene product p21 in the human endometrium. Specimens obtained from 25 normal, 31 hyperplastic and 72 malignant samples of the human endometrium were examined for point mutation in codons 12, 13 and 61 of the c-K-ras by direct sequencing and c-erbB-2 gene amplification with p185 and p21 expression by differential polymerase chain reaction (DPCR) and immunohistochemistry. Neither the normal endometrium nor endometrial hyperplasias were found to have mutations in the c-K-ras gene, although a double mutation of codons 12 and 13 as a single-point mutation was observed in one case of endometrioid carcinoma (2.8%). In each of two other cases of endometrioid carcinoma (2/72), two single-point mutations of codon 13 (5.6%) were shown. Using DPCR, we found c-erbB-2 to be amplified in 15 premalignant (48%) and 45 malignant (63%) samples. We noticed that nonamplification of the c-erbB-2 gene was associated with the absence of immunoreactivity. Our data indicate that, while c-erbB-2 plays a role in the early development of endometrioid carcinomas, c-K-ras gene activation by point mutation does not.

Salivary duct carcinoma (SDC) is a highly malignant salivary gland tumor with aggressive clinical behavior, and is characterized by its histological resemblance to invasive ductal carcinoma of the breast. Overexpression and/or amplification of proto-oncogene Her2/neu has been shown to influence both prognosis and treatment of breast cancer. Since salivary duct carcinoma and ductal breast carcinoma share many common characteristics, HER2/neu overexpression might also be important in SDC. However, data on the expression of c-erbB2/HER2/neu in salivary gland tumors are still scarce. Therefore, we have evaluated 15 cases of salivary duct carcinomas (SDC) for HER2/neu overexpression using immunohistochemistry with the HercepTest. Overexpression, identified as strong or moderate membrane immunostaining, was observed in ALL but one case of SDC in most neoplastic cells. Thus, our study suggests that anti-HER2/neu therapy with Herceptin is beneficial for patients with aggressive salivary duct carcinoma.

The relatively high incidence of amplification and overexpression of the neu (c-erb B2/HER-2) oncogene in breast cancer, and its association with poor prognosis, particularly in node negative patients, may allow identification of patients who require aggressive therapy to prevent an early relapse. It s association with ovarian cancer, however, is less well defined than in breast cancer. An ELISA for the c-neu proto-oncogene related protein, p185, has been developed recently using the monoclonal antibodies NB3 and TA1. In the first study of it s kind, we assayed serum samples from patients with primary epithelial ovarian cancer for circulating c-neu p185. Elevated levels were found in 21/178 (11.8%) patients. No correlation was found between serum levels and either the presence or volume of tumor, when assessed either after primary or at second-look surgery. A change in c-neu p185 levels did not correlate with response to chemotherapy. When subjected to univariate and multivariate analyses together with other known prognostic factors, serum c-neu p185 was not a significant predictor of progression-free survival or overall survival. Although c-neu p185 may be involved in the pathogenesis of ovarian cancer, it s assay in serum has no value in prognosis or monitoring.

Amplification and/or increased expression of the HER-2/neu oncogene has been reported to occur in ovarian tumors and possibly to correlate with biologic behavior and prognosis. The frequency with which amplification is reported to occur is quite variable ranging from 0-30% in different series and this variability is probably accounted for by technical and methodologic factors. The variability and lack of reproducibility has raised questions about the usefulness of assessing amplification of the HER-2/neu oncogene and in particular its clinical relevance. In this study by using strict criteria for amplification and using multiple controls we could demonstrate unequivocal amplification of the HER-2/neu oncogene by Southern blot analysis in only 11% of malignant ovarian tumors. The potential pitfalls with the techniques used to detect HER-2/neu oncogene amplification and overexpression are reviewed and possible ways to overcome some of the problems are suggested.

Serum CA 125 levels were evaluated in 26 patients with fallopian tube malignancies. CA 125 was elevated preoperatively in seven samples (median 178 U ml-1 range 41-19021 U ml-1), and postoperatively in eight of nine (89%) samples collected from patients with residual disease (median 109 U ml-1 range 10-1883 U ml-1) but only in one of seven (14%) samples from patients without residual disease (median 14, range 5-170 U ml-1) (P < 0.001). Changes in the serum CA 125 level during chemotherapy correlated with the clinical course of disease in 13 of 14 patients with a pre-chemotherapy serum CA 125 level> 35 U ml-1. Nine patients with clinical remissions showed decreasing serum CA 125 levels, one with clinically stable disease showed decreasing levels and four with disease progression showed increasing levels. Serum CA 125 levels were measured in four patients before second-look laparotomy. Two of three with positive findings at laparotomy had elevated serum CA 125 levels whilst the third had a normal level. One patient with negative findings at second-look surgery had a normal CA 125 level. disease relapse was associated with elevated serum CA 125 levels in nine of 10 patients (median 108 U ml-1, range 27-38200 U ml-1). Using immunohistochemical staining, none of the tumors showed positive cytoplasmic staining for c-erbB-2 (NEU) oncogene. This report shows that CA 125 is a reliable tumor marker for monitoring patients with cancer of the fallopian tube during active treatment and follow-up.

The immunohistochemical expression of HER-2/neu and cytofluorimetric data were retrospectively analyzed in a group of primary advanced ovarian cancers. Thirty-three out of 94 (35%) cases showed a specific p185/neu immunoreaction. No correlation between p185/neu expression and any of the clinico-pathologic parameters examined was observed. As far as cytofluorimetric data are concerned, 38 out of 69 (55%) of the tumors were diploid (DNA index = 1) while 31 (45%) were aneuploid (DNA index from 1.10 to 2.50 with a median value of 1.50). Ovarian tumors were defined as of low and high S-phase fraction in 68% and 32% of the cases, respectively. tumor ploidy and S-phase fraction did not correlate with the clinico-pathologic characteristics or p185/neu oncoprotein expression. Aneuploid tumors had a higher S-phase fraction (mean: 15.81 +/- 13.44) than diploid tumors (mean: 8.89 +/- 7.98) (P < 0.01). p185/neu expression failed to affect significantly both overall and progression free survival. On the other hand tumor ploidy was found to be related to the prognosis of advanced ovarian cancer patients although the difference was not statistically significant. As far as progression free survival is concerned, the median time to recurrence was not reached for diploid cases whereas it was 21 months for aneuploid cases (P < 0.05). The 5-year survival for patients with a low S-phase fraction (58%) was significantly higher than for patients with high S-phase fraction tumors (28%) (P < 0.01). Median time to recurrence was 48 and 17 months for low and high S-phase fraction tumor patients, respectively (P < 0.05). However, in a multivariate analysis both tumor ploidy and S-phase fraction did not retain their prognostic value. The assessment of the role of the parameters examined in improving the prognostic characterization of ovarian cancer patients should be investigated in large multicenter clinical trials.

The expression of c-erbB-2 oncogene has been studied in 74 formalin fixed paraffin embedded invasive epithelial ovarian malignancies using a monoclonal c-erbB-2 protein antibody. Only four (5.4%) tumors showed membrane immunostaining. FIGO stage, size of residual disease after primary surgery, histologic type and tumor grade, were identified by the log rank test as prognostic factors for survival. No difference in survival was observed between those with and without membrane staining (24 months probability of survival: 50% and 55.4% respectively). Our results did not show any adverse prognostic effect of c-erbB-2 protein expression in our patients.

We developed a multiparameter flow cytometric technique for the simultaneous measurement of cellular DNA content and c-erbB-2 or epidermal growth factor receptor (EGFR) expression. The method provides a high resolution of DNA content and well preserved c-erbB-2 and EGFR immunostaining under saturated antibody conditions, allowing good control for background fluorescence and satisfactory cell morphology. Four different protocols for the short-term preservation of cells used for multiparameter flow cytometric assay of EGFR and c-erbB-2 were assessed in cell suspensions prepared by mechanical disaggregation in 10 gynecologic tumors. The protocols at 4 degrees C were: storage in 50% methanol, and storage in buffer after formalin fixation. Tissues were also cryopreserved as cell suspensions and tissue blocks. When the oncoprotein expression and DNA histograms were compared with those in fresh suspensions, cryopreservation was found to be the best method: oncoprotein expression was well preserved and there was a good correlation between oncoprotein expression and the quality of the DNA histograms. The currently developed methods for cell preservation make the technique generally available for clinical cancer studies.

To investigate the frequency of HER-2 oncogene amplification in primary hepatocellular carcinoma (HCCs) and its relationships with clinicopathological parameters and prognosis, 42 surgical samples from patients with primary HCCs were detected for their HER-2 oncogene amplification by dual FISH technique, and then the correlations between HER-2 amplification and clinicopathological characteristics and prognosis were analyzed statistically. HER-2 oncogene amplification was detected in 9 of 42 (21.4%) primary HCCs, including 4 (9.5%) cases with high copy (HC) and 5 (11.9%) ones with low copy (LC). HER-2 amplification was associated significantly with postoperative survival time of HCC patients examined (P = 0.046) and the presence of HER-2 gene amplification showed a trend toward a correlation with tumor size (P = 0.085), but wasn t relative to sex, age, AFP level, HBV infection, postoperative relapse and clinical staging of HCC patients tested (P > 0.05). On the other hand, gain of the HER-2 oncogene copy was examined in 31 of 42(73.8%) primary HCCs, consisting of 9 (21.4%) cases with HER-2 amplification and 22(52.4%) ones with aneusomy 17/polysomy 17. There weren t significant relationships between gain of HER-2 oncogene copy and, HCC patient s sex, tumor size, clinical staging, postoperative relapse and survival time (P > 0.05), but gain of HER-2 oncogene copy correlated significantly to patients age, AFP level and HBV infection (P < 0.05). The study indicated that there were a lower frequency of HER-2 oncogene amplification and a higher frequency of aneusomy 17/polysomy 17 in primary HCCs and that HER-2 oncogene amplification activation might be involved in the development and progression of a subset of HCCs, and seemed to be a valuably independent prognosis factor predicting postoperative poorer survival for patients with HCC.

Novel systemic treatments are needed in pancreatic cancer. The authors sought to establish the frequency of overexpression of the HER-2/neu oncogene in patients with pancreatic adenocarcinoma to determine the potential role of trastuzumab (Herceptin) as a therapeutic agent in this disease. tumor specimens from patients with pancreatic adenocarcinoma were analyzed by staining for p185HER2 protein using the DAKO immunohistochemical assay. Patients with and without HER-2/neu overexpression by immunohistochemistry were compared with respect to clinical and pathologic characteristics. HER-2/neu gene amplification was also evaluated by fluorescence in situ hybridization (FISH). Thirty-two of 154 patients (21%) had pancreatic adenocarcinoma that demonstrated HER-2/neu overexpression by immunohistochemistry. At initial diagnosis, 16% of resectable cancers, 17% of locally advanced cancers, and 26% of metastatic cancers were determined to have HER-2/neu overexpression. Three of 11 (27%) patients with HER-2/neu overexpression by immunohistochemistry had gene amplification by FISH. HER-2/neu overexpression occurs in a subset of pancreatic cancer. Evaluation of the efficacy of trastuzumab for patients with pancreatic cancer who overexpress HER-2/neu appears indicated.

In this study we initially examined the interaction between CD44v3 (a hyaluronan (HA) receptor) and Vav2 (a guanine nucleotide exchange factor) in human ovarian tumor cells (SK-OV-3.ipl cell line). Immunological data indicate that both CD44v3 and Vav2 are expressed in SK-OV-3.ipl cells and that these two proteins are physically linked as a complex in vivo. By using recombinant fragments of Vav2 and in vitro binding assays, we have detected a specific binding interaction between the SH3-SH2-SH3 domain of Vav2 and the cytoplasmic domain of CD44. In addition, we have observed that the binding of HA to CD44v3 activates Vav2-mediated Rac1 signaling leading to ovarian tumor cell migration. Further analyses indicate that the adaptor molecule, growth factor receptor-bound protein 2 (Grb2) that is bound to p185(HER2) (an oncogene product), is also associated with the CD44v3-Vav2 complex. HA binding to SK-OV-3.ipl cells promotes recruitment of both Grb2 and p185(HER2) to the CD44v3-Vav2 complex leading to Ras activation and ovarian tumor cell growth. In order to determine the role of Grb2 in CD44v3 signaling, we have transfected SK-OV-3.ipl cells with Grb2 mutant cDNAs (e.g. Delta N-Grb2 that has a deletion in the amino-terminal SH3 domain or Delta C-Grb2 that has a deletion in the carboxyl-terminal SH3 domain). Our results clearly indicate that the SH3 domain deletion mutants of Grb2 (i.e. the Delta N-Grb2 (and to a lesser extent the Delta C-Grb2) mutant) not only block their association with p185(HER2) but also significantly impair their binding to the CD44v3-Vav2 complex and inhibit HA/CD44v3-induced ovarian tumor cell behaviors. Taken together, these findings strongly suggest that the interaction of CD44v3-Vav2 with Grb2-p185(HER2) plays an important role in the co-activation of both Rac1 and Ras signaling that is required for HA-mediated human ovarian tumor progression.

OBJECTIVE: To investigate the status of her2 oncogene at DNA level and the molecular mechanism of overexpression of her2 oncoprotein in part of patients with nasopharyngeal carcinoma (NPC). METHODS: Forty-five cases of PNC tissue and fifteen cases of normal epithelial tissue adjacent to tumor tissue were examined for her 2 signal and centromere 17 signal. Interphase fluorescence in situ hybridization (FISH) was used to examine the copy number of her 2 and immunohistochemical (IHC) staining were used to analyze the copy number and protein expression of her2. RESULTS: There were 1.92% +/- 0.10% her2 signals per nucleus in normal epithelial tissue adjacent to tumor. 75.52 +/- 9.33% of the nuclei contained 2 her2 signals and 2 centromere 17 signals. No alteration in gene copy number was found in cancerous nuclei. However, IHC staining of the 45 tumors with antibody against her2 showed that overexpression of her2 oncoprotein occurred in 33% (15/45) of NPC. However, there was no significant correlation between her2 expression and sex, age, clinical staging, and clinical outcome of patients. CONCLUSION: The overexpression of her2 in NPC does not relate to her2 gene amplification. Immunohistochemistry may not be a good measure to examine her2 expression. The mechanism of her2 oncoprotein overexpression and its biological significance in the development of NPC remain to be elucidated.

BACKGROUND: c-erbB-2 is a transmembrane signaling molecule closely related in structure to the epidermal-growth-factor receptor (EGFR) but biologically distinct from it. c-erbB-2 has been implicated in cell transformation and tumor pathogenesis, but very little is known about its content and clinical significance in colorectal cancer. AIMS: To evaluate the c-erbB-2 content in colorectal cancer and its possible relationship with clinicopathologic parameters from tumors and prognostic significance. METHODS: Membranous and cytologic c-erbB-2 oncoprotein contents were examined by an immunoenzymatic assay in tumors and paired normal surrounding mucosa samples from 131 colorectal cancer patients. In addition, survival analysis were prospectively performed in a subgroup of 69 consecutive patients with resectable colorectal carcinomas, who underwent a mean follow-up period of 28 months. RESULTS: In the overall group of patients, c-erbB-2 levels were significantly higher in membranous than in cytosolic samples, in neoplastic tissues (5,830.4 +/- 1085.3 vs. 934.2 +/- 107.5 NHU/mg protein; p < 0.0001) and in surrounding normal mucosa samples (5,257.8 +/- 646.3 vs. 837.4 +/- 187.4 NHU/mg protein; p < 0.0001). Nevertheless, a significant positive relation was found between membranous and cytosolic oncoprotein levels in these two paired sets (p < 0.0001, for both). There were no significant differences in membranous or cytosolic c-erbB-2 protein levels between neoplastic tissues and surrounding mucosa samples in this overall group of patients. In addition, the results did not show significant correlations of these oncoprotein contents with clinicopathologic parameters from tumors such as location, stage, histologic grade, and DNA content or S-phase fraction. However, the results indicated that low membranous c-erbB-2 content (< 4,500 NHU/mg protein) in tumors predict shorter relapse-free survival and overall survival (p < 0.05, for both) in resectable colorectal cancer patients. CONCLUSIONS: There are a wide variability of both membranous and cytologic c-erbB-2 contents in colorectal carcinomas, which seems to correspond to the biological heterogeneity of these tumors. In addition, our results also demonstrate that high membranous c-erbB-2 levels are associated with lesions of favorable evolution in resectable colorectal cancer patients.

BACKGROUND: HER-2/neu tissue overexpression is found in nearly 15% of patients with nonsmall cell lung carcinoma and is reported to affect prognosis adversely in surgical series. However, the prognostic role of serum HER-2/neu oncoprotein, particularly in patients with advanced lung carcinoma, remains unknown. This study was designed to assess the potential value of measuring serum levels of HER-2/neu oncoprotein in predicting response to treatment and survival in patients with locally advanced and metastatic nonsmall cell lung carcinoma. METHODS: Baseline serum HER-2/neu levels (fm/mL) were studied using an enzyme-linked immunosorbent assay method in 84 patients with newly diagnosed, advanced nonsmall cell lung carcinoma who underwent chemotherapy. RESULTS: The patients enrolled in the study included 76 males and 8 females, with a median age of 62 years (range, 36-73 years) and a median performance status of 1. Fifty patients (59.5%) had nonsquamous histology, and 34 patients (40.5%) had squamous cell carcinoma. Thirty-four patients (40.5%) had Stage III disease, and 50 patients (59.5%) had Stage IV disease. The mean baseline value of HER-2/neu in the whole series was 56.1 fm/mL (range, 13.0-103.8 fm/mL). HER2 immunohistochemistry on paraffin embedded tissue was performed in 18 patients. HER-2/neu tissue overexpression was found in only one patient, who also showed high serum levels (102 fm/mL). No correlation was observed between protein serum quantitation and gender, age, histology, stage, performance status, leukocyte count, or smoking. Nonresponding and responding patients exhibited similar oncoprotein levels (median, 57.6 fm/mL vs. 51.9 fm/mL, respectively). The overall survival rate was 42.5% at 1 year and 12% at 2 years, with a median survival duration of 10 months. At univariate analysis, high HER-2/neu serum levels were associated with an unfavorable survival outcome. Using a cut-off point for HER-2/neu of 73.0 fm/mL (corresponding to the 80th percentile of protein concentration), the survival of patients who had higher serum levels of HER-2/neu was significantly worse compared with patients who had lower serum levels (median, 7.1 months vs. 10.9 months; P = 0.004). Multivariate analysis confirmed the independent predictive value of serum HER-2/neu concentration as a negative prognostic factor (P = 0.02). CONCLUSIONS: High pretreatment levels of HER-2/neu oncoprotein are associated with an adverse prognostic impact on survival in patients with locally advanced or metastatic nonsmall cell lung carcinoma.

Overexpression of human epidermal growth factor receptor-2 (HER-2) oncoprotein is an important prognostic factor associated with a poor prognosis in breast cancer. Although treatment with trastuzumab, an anti-HER-2 antibody, increases drug-sensitivity in vitro and in vivo, the role of HER-2 oncoprotein in drug-sensitivity is still uncertain. The present work discusses the clinical significance of the HER-2 oncoprotein in drug-sensitivity in breast cancer based on previous clinical and basic results and reviews the current concept of HER-2 oncoprotein in drug-sensitivity. Introduction of HER-2 oncoprotein in vitro induces resistance to several anticancer drugs, including taxanes, cisplatin (CDDP) and 5-fluorouracil (5-FU) in breast cancer cells. The acquisition of drug-resistance by introduction of the HER-2 gene, however, depends on the cell type, because transfection of the HER-2 gene per se does not necessarily induce resistance to the same drugs in ALL types of breast cancer cells. In clinical studies, patients with HER-2 overexpression responded better to an anthracycline-based regimen than patients with low HER-2 expression, and their overall survival was also superior. In contrast, a correlation between the response to a cyclophosphamide + methotrexate + 5-FU regimen and overexpression of HER-2 is not certain. Taxanes responsiveness in patients with HER-2 oncoprotein overexpression was superior in patients with low HER-2 expression. Treatment with trastuzumab increased drug-sensitivity to anthracyclines, CDDP, and taxanes, but not to 5-FU, in breast cancer cells. Although the mechanism(s) by which trastuzumab enhances drug-sensitivity is not fully understood, modulation of the signal transduction pathways leading to apoptosis, such as down-regulation of the anti-apoptotic protein, Bcl-2, might be an important target to increase drug-sensitivity in breast cancer. HER-2 overexpression can be a good indicator for the selection of aniticancer drugs, especially for anthracycline containing regimens. To modulate HER-2-targeting therapy, the mechanism(s) by which trastuzumab enhances drug-sensitivity requires elucidation at the molecular level, including determination of other factors that influence drug-sensitivity, leading to a more promising treatment for individual patients receiving combination therapy with trastuzumab and anticancer drugs for breast cancer.

To date there are no prognostic factors that can account for the biology and disease behavior in nasopharyngeal cancer. Therefore, identification of new factors that can help in predicting the behavior of the disease and characterizing the subgroup with more aggressive tumors more likely to benefitfrom chemotherapy is important. In this study, c-erb B2, bcl-2, and mutant p53 protein levels were investigated in sera and tumor tissue of patients with nasopharyngeal cancer. Serum c-erb B2 levels were significantly higher in the patients than in the healthy subjects. No meaningful difference was observed between the serum and tissue levels of the mutant p53 protein. Tissue bcl-2 concentrations were considerably high. Our results suggest that serum c-erb B2 levels may aid in identifying a subgroup of patients with a poorer response rate to first-line treatment.

Several advances in basic immunology over the last few years have forced a re-evaluation of cancer vaccine development. The most important finding has been that human tumors are immunogenic. The HER2/neu oncogenic protein is a tumor antigen. Existent antibody, helper T-cell, and cytotoxic T-cell immunity to HER2/neu have been detected in patients with cancer. The HER2/neu protein is an excellent therapeutic target for the immune system. Passive immunotherapy strategies, such as the infusion of monoclonal antibodies specific for HER2/neu, have been shown to be of clinical benefit in patients with HER2/neu-overexpressing malignancies. Inducing an active immune response by generating endogenous HER2/neu-specific antibodies and T cells may result in long-lived immunity and, hopefully, therapeutic benefit. In the majority of patients with pre-existent HER2/neu immunity, the antigen-specific antibodies and T cells detected are of low magnitude. Therefore, vaccine strategies aimed at boosting immunity already present may be effective in generating significant levels of HER2/neu-specific antibodies and T cells.

OBJECTIVE: To construct in vitro transcription vectors of genes of c-erbB-2 specific ribozyme and its substrate and to probe its in vitro cleavage action. METHODS: According to the computer design, a specific restriction site EcoR V was added to the 3 end of the ribozyme gene (RZ1). Then, the RZ1 gene and its substrate gene were cloned into the in vitro transcription vector pGEM3Zf(-) separately. The recombinants containing RZ1 gene were first screened by agrose ge1 electrophoresis through EcoR V digestion and was identified by automatic sequencing. The products of in vitro transcription were labeled with 32P. In vitro cleavage reaction was performed at 37 degrees C for 1 h under the presence of Mg++. The cleavage product was analyzed by polyacrilamide gel electrophoresis. After autoradiography, the cleavage rate was counted by image analysis. RESULTS: The recombinants containing the RZ1 gene were successfully selected by the EcoR V digestion and were designated as pGM3Z-RZ1. The automatic sequence analysis proved that the synthesized RZ1 gene was correct. The target gene was also cloned into the pGEM3Zf(-) under SP6 promoter. After in vitro transcription, the cleavage reaction was shown to have cut off 79.3% target RNA in 1 h. CONCLUSION: The c-erbB-2 oncogene-specific ribozyme has a high activity in vitro. It lays a foundation for the study of the therapeutic use of ribozyme in gene therapy of cancer.

OBJECTIVE: To study relationship of C-erb-2 oncogene mRNA expression and histotype, tumorigenesis and biological behavior of salivary gland neoplasms. METHODS: Using 32P labeled oligonucleotide as probe, the dot blot technique was used to study the expression of C-erbB-2 oncogene mRNA in salivary gland neoplasm with normal salivary gland as control. RESULTS: With the expression in normal salivary gland as a standard, low C-erbB-2 mRNA expression was seen in adenolymphoma, basal cell adenoma. However, various degrees of over-expression of C-erbB-2 oncogene mRNA were detected in pleomorphic adenoma, mucoepidermoid carcinoma, acinic cell carcinoma, adenoid cystic carcinoma, papillary cystic carcinoma, and myoethelial cell carcinoma. CONCLUSION: C-erbB-2 oncogene mRNA over-expression in salivary gland neoplasm is related to biological behavior of salivary gland carcinoma.

Her-2/neu belongs to the family of tyrosine kinase transmembrane proteins whose overexpression has been associated with a poor prognosis in patients with breast cancer. The product of this proto-oncogene is overexpressed in 25-30% of human breast cancer and is the target of selective immunotherapy. Concerned about the ethnic differences on the expression of this oncogene, we have evaluated 143 consecutive specimens of primary breast cancer diagnosed in San Pablo Hospital, Puerto Rico. The specimens were analyzed for Her-2/neu expression using immunohistochemistry assays (Hercept test). We have related the expression of hormone receptor status, percent cells in S phase, DNA ploidy, tumor size, nodal status and menopausal state with the Her2/neu expression. Out of 143 specimens, 28 overexpressed the Her-2/neu (19.6%). Of the Her/2 negative 30/114 (26%) were estrogen receptor negative as compared to 9/27 (33%) (p = 0.464). The degree of aneuploidy was abnormal in 25/104 (24%) in the Her-2/neu negative vs 11/27 (41%) p = 0.083. The percent cell in DNA synthesis was high in 16/77 (21%) in Her-2/neu negative vs 4/15 (27%) p = 0.613. The tumor size was greater than 2 cm in 35/106 (33%) in Her-2/neu negative vs 9/23 (39%) p = 0.575. In the progesterone specimens negative for Her2, 44/114 (39%) were Her2/neu negative vs 15/27 (56%) p = 0.108. No differences were seen regarding menopausal status, age and nuclear grading. A trend favoring abnormal aneuploidy in Her2/neu positive was seen. Nodal involvement was significantly associated with Her2/neu overexpression. (p = 0.037). Although the incidence of Her2 overexpression found in this database was somewhat lower than the one reported in the literature, this might also be due to the small cohort examined or to the technique utilized.

An anti-ERBB2 antibody, trastuzumab, has been shown to be highly efficient in the treatment of metastatic breast cancers overexpressing the ERBB2 gene. It has been suggested that overexpression and even amplification of ERBB2 may play a role in the development of prostate cancer. Here, we have analyzed gene copy number and expression of the ERBB2 gene in both androgen-dependent primary and metastatic tumors, as well as recurrent hormone-refractory tumors. The expression levels were compared to the expression of ERBB2 in breast cancers with or without ERBB2 gene amplification. Of 126 prostate tumors, chromogenic in situ hybridization (CISH) revealed only 1 case containing borderline (six to eight copies) amplifications of ERBB2. This hormone-refractory tumor, however, did not express ERBB2 protein. Immunohistochemical staining of ERBB2 protein was negative (0 or 1+ intensity) in ALL prostate samples (n = 124) analyzed. To quantitate the level of ERBB2 mRNA expression in prostate tumors (n = 34) and cell lines (n = 3), as well as in breast tumors (n = 30) and cell lines (n = 16), real-time reverse transcriptase-polymerase chain reaction (LightCycler) methodology was used. The expression level was similar in ALL prostate tumor types and corresponded to the level of expression in breast carcinomas without ERBB2 amplification. Breast tumors with ERBB2 amplification expressed, on average, approximately 20 times (P < 0.001) higher mRNA levels than prostate tumors or breast carcinomas without the gene amplification. In conclusion, the expression of ERBB2 in prostate cancer is relatively low, and is not altered during disease progression. Thus, it is unlikely that treatment modalities relying on the overexpression of ERBB2 gene will be useful in treating prostate cancer.

The use of adenovirus (Ad) vectors for cancer gene therapy applications is currently limited by several factors, including broad Ad tropism associated with the widespread expression of coxsackievirus and adenovirus receptor (CAR) in normal human tissues, as well as limited levels of CAR in tumor cells. To target Ad to relevant cell types, we have proposed using soluble CAR (sCAR) ectodomain fused with a ligand to block CAR-dependent native tropism and to simultaneously achieve infection through a novel receptor overexpressed in target cells. To confer Ad targeting capability on cancer cells expressing the c-erbB-2/HER-2/neu oncogene, we engineered a bispecific adapter protein, sCARfC6.5, that consisted of sCAR, phage T4 fibritin polypeptide, and C6.5 single-chain fragment variable (scFv) against c-erbB-2 oncoprotein. Incorporation of fibritin polypeptide provided trimerization of sCAR fusion proteins that, compared with monomeric sCAR protein, resulted in augmented affinity to Ad fiber knob domain and in increased ability to block CAR-dependent Ad infection. We demonstrated that sCARfC6.5 protein binds to cellular c-erbB-2 oncoprotein and mediates efficient Ad targeting via a CAR-independent pathway. As illustrated in cancer cell lines that overexpress c-erbB-2, targeted Ad, complexed with sCARfC6.5 adapter protein, provided from 1.5- to 17-fold enhancement of gene transfer compared with Ad alone and up to 130-fold increase in comparison with untargeted Ad complexed with sCARf control protein. The use of recombinant trimeric sCAR-scFv adapter proteins may augment Ad vector potency for targeting cancer cell types.

AIM:To study the significance of C-erbB-2 oncogene amplification in gastric cancer.METHODS:C-erbB-2 oncogene amplification was examined by using differential polymerase chain reaction (dPCR) in surgical and endoscopic specimens of 83 cases of gastric cancer and 101 metastatic lymph nodes.RESULTS:C-erbB-2 amplification was found in 28.9% (24/83) surgical specimens and 20.5% (17/83) endoscopic ones of gastric cancer patients.The amplification was significant in both types of specimens of advanced cancer cases (P < 0.05) and surgical specimens with lymph node metastasis (P <0.01). The incidence of C-erbB-2 amplification in lymph nodes with metastasis was higher than in primary sites (surgical specimens, P < 0.05). The patients with amplification tumors had poorer 5-year survival rates than those with unampli-fication ones in the early cancers and well to moderately differentiated adeno-carcinomas (P <0.05). The same surgical samples were tested again by Southern blot hybridization to ascertain C-erbB-2 amplification, and the positive rate of C-erbB-2 amplification (15.7%) was lower than that of dPCR (28.9%, P < 0.05).CONCLUSION:Examining C-erbB-2 amplification by dPCR is a quick, simple, reliable and independent method, and is helpful in predicting prognosis and metastatic potential of gastric cancer.

The aim of this study was to investigate the expression of the oncogene c-erbB-2 in gastric tumors. Immunohistochemical study of the expression of c-erbB-2 was performed in formalin-fixed, paraffin-embedded sections from 82 gastric adenocarcinomas using polyclonal antibody. c-erbB-2-positive immunostaining was observed in 37 (45%) tumors. Positive staining was detected in 63% of well differentiated, 46% of moderately differentiated and 80% of papillary adenocarcinomas. In poorly differentiated adenocarcinomas, positivity for c-erbB-2 was observed in 21 %. According to the Lauren classification, a higher frequency of c-erbB-2 positive staining was observed in intestinal type tumors (70%). During the follow-up period 43% of the patients with c-erbB-2 oncoprotein-negative tumors and 45% of the patients with c-erbB-2 oncoprotein-positive tumors died. There was no significant association between c-erbB-2 staining and sex, age, clinical stage, tumor grade, histological type or survival rates. In conclusion, almost half of the gastric cancers were positive for c-erbB-2. Nonetheless, the expression of c-erbB-2 oncoprotein did not play a role in prognosis.

OBJECTIVE: To explore the effect of expression of epidermal growth factor receptor (EGFR), transforming growth factor beta (TGF beta), c-erbB-2 oncogene in myoepithelioma and malignant myoepithelioma. METHODS: 20 cases of myoepithelioma and 20 cases of malignant myoepithelioma were examined by immunohistochemical methods. RESULTS: ALL cases showed overexpression of EGFR and TGF beta, the intensity of expression didn t associate with the benignity and malignity of tumors. The overexpression of c-erbB-2 oncoprotein was seen in 5 cases of myoepithelioma and 13 cases of malignant myoepithelioma, and the cases of malignant myoepithelioma were stained more intense than that of myoepithelioma. CONCLUSION: The synergy of EGFR and TGFR beta had significant relation to the proliferative and differentiation processes of myoepithelial tumor. The activated c-erbB-2 oncogene, that is similar with EGFR in structure, plays an important promoting role in unrestricted progression of malignant myoepithelioma cells.

PURPOSE: The role of HER-2/neu in squamous cell carcinoma (SCC) of the head and neck is not well defined. The purpose of the current study is to measure the frequency of HER-2/neu expression, to demonstrate HER-2/neu gene amplification in the cases found to be positive for protein overexpression, and to investigate the prognostic significance of overexpression and/or amplification in SCC of the head and neck. EXPERIMENTAL DESIGN: A cohort of 77 patients with SCC of the oral cavity or oropharynx, with stage III or IV disease and uniformly treated with surgical resection and postoperative radiation, served as the primary patient population for the study. Of these, 56 patients had adequate follow-up and paraffin-embedded specimens available for analysis. Median follow-up was 6.1 years. Each of the paraffin-embedded specimens were immunohistochemically stained for HER-2/neu expression and graded for intensity of staining by a pathologist. ALL cases that demonstrated positive staining by immunohistochemistry were analyzed by fluorescence in situ hybridization (FISH) to assess HER-2/neu amplification status. RESULTS: Five-year survival for the 56 evaluable patients was 40%, with 25% experiencing local relapse, 18% regional relapse, and 25% distant relapse. The percentage of tumors staining positive for HER-2/neu by immunohistochemistry was 17%. There was no statistically significant correlation between HER-2/neu and T stage, N stage, tumor grade, survival, or disease-free survival. HER-2/neu expression did correlate with vascular endothelial growth factor expression. FISH analysis revealed four cases that were amplified for HER-2/neu. Of note, of the 4 amplified cases, 2 suffered regional relapse, 1 suffered distant metastasis, and ALL 4 expired by 5 years of follow-up. CONCLUSIONS: This is the first demonstration of HER-2/neu gene amplification by FISH in SCC of the head and neck. FISH validates a previously contested controversial role for HER-2/neu gene overexpression in SCC of the head and neck. The prognostic significance and clinical implications of HER-2/neu expression and amplification in head and neck cancer will require additional studies.

The C-erbB-2 proto-oncogene encodes the production of a cell surface receptor protein, with tyrosine kinase activity. Over expression of this gene either due to gene amplification and/or increased transcription has been observed and has been correlated with poor prognosis in patients with Breast (10-33%) and ovarian (20-33%) cancers. The very low levels of expression of C-erbB-2 by normal tissues makes this receptor a potential target for diagnosis and therapy with Monoclonal antibodies raised against its extracellular domain. One such monoclonal antibody designated as CIBCgp185 of IgG2a isotype has been generated in our laboratory using BT474 breast carcinoma cell line as immunogen. This monoclonal antibody immunoprecipitated a 185 KD glycoprotein. The specificity of this antibody was confirmed by the formation of a single discrete band and positive reaction with BT474 antigen in Western blot and Dot blot respectively. Flowcytometric analysis performed using various cancer cell lines revealed that this Monoclonal antibody exhibited high binding affinity with BT474 and SKBR3 cells whichoverexpresses C-erbB-2. By immunoperoxidase test, this antibody stained specifically the tumor cell membrane in frozen tissue sections of breast and ovarian tumors indicating overexpression of the C-erbB-2 product. ALL these results well correlated with those obtained using a control antibody ICR12, an anti-C-erbB-2 antibody. These studies clearly indicate that Monoclonal antibody CIBCgp185 might prove useful to identify tumors with over expression of C-erbB-2 which are often associated with poor prognosis and early recurrence.

AIM: To examine the incidence of Her-2/neu oncogene amplification in clinically localised prostate cancer using in situ hybridisation. METHODS: One hundred and seventeen patients, who had undergone radical prostatectomy, were identified and in situ hybridisation was performed on formalin fixed, paraffin wax embedded tissue using the Quantum Appligene probe for Her-2/neu. The enzyme peroxidase was used to detect the probe because this enabled a permanent record to be kept. tumours in which there were five or more signals in each nucleus in > 20% of the tumour cells were considered to have a significantly increased copy number. A serial section from these tumours was then hybridised with the chromosome 17 alpha satellite probe. The ratio of the percentage of cells showing an increase in Her-2/neu copy number to the number showing polysomy for chromosome 17 was calculated. A ratio above 2 was considered amplified. RESULTS: Biochemical recurrence occurred in 50 (43%) patients and 24 (21%) had clinical recurrence. In situ hybridisation for Her-2/neu was accessible in 114 (97%) patients. A significant increase in copy number was present in two patients (1.75 %), but chromosome 17 hybridisation showed that the increase was the result of polysomy rather than true amplification. Both these patients had a Gleason score of 7 and stage T3; they also had recurrent clinical disease with distal metastasis within two and 19 months. CONCLUSIONS: Increased Her-2/neu oncogene copy number appears to be rare in clinically localised prostatic adenocarcinoma and is related to chromosome 17 polysomy rather than true amplification. As a result, it would not be a useful biomarker for identifying those patients who will have recurrences after radical prostatectomy.

Previous studies showed that antagonists of bombesin (BN)/gastrin-releasing peptide (GRP) inhibit the growth of various cancers by interfering with the growth-stimulatory effects of BN-like peptides and down-regulating epidermal growth factor receptors on tumors. Because the overexpression of the human epidermal growth factor receptor-2 (ErbB-2/HER-2/neu) oncogene plays a role in the progression of many breast cancers, we investigated whether BN/GRP antagonists can affect HER-2 in mammary tumors. Female nude mice bearing orthotopic xenografts of MDA-MB-435 human estrogen-independent breast cancers were treated daily with BN/GRP antagonists RC-3095 (20 microg) or RC-3940-II (10 microg) for 6 weeks. The expression of BN/GRP receptors on tumors was analyzed by reverse transcription-PCR and immunoblotting. We also evaluated whether the mRNA expression for the c-jun and c-fos oncogenes is affected by the therapy. Both BN/GRP antagonists significantly inhibited growth of MDA-MB-435 cancers; RC-3095 reduced tumor volume by 40% and RC-3940-II by 65%. The GRP receptors (subtype 1) were detected in MDA-MB-435 tumors, showing that they mediate the inhibitory effect of the antagonists. tumor inhibition was associated with a substantial reduction in the expression of mRNA and protein levels of the ErbB/HER receptor family as well as with a decrease in the expression of c-jun and c-fos oncogenes. BN/GRP antagonists RC-3940-II and RC-3095 could be considered for endocrine therapy of estrogen-independent breast cancers that express members of the ErbB/HER receptor family and the c-jun and c-fos oncogenes.

BACKGROUND: Abnormal expression of the HER-2/neu oncogene, a tyrosine kinase-type transmembrane growth factor receptor localized to chromosome 17q, has been associated with poor prognosis and the prediction of therapy response in invasive breast cancer. The comparative incidence and significance of HER-2/neu gene amplification for lobular and ductal breast cancer have not been previously characterized. DESIGN: Formalin-fixed, paraffin-embedded primary breast cancer tissue sections from 71 women diagnosed with invasive lobular carcinoma were tested for HER-2/neu gene amplification by fluorescence in situ hybridization (FISH) method using the Ventana unique sequence probe (Ventana Medical Systems, Tucson, AZ). A series of 106 cases of invasive ductal carcinoma was similarly processed and tested. Lymph node status was available for 155 (88%) of the 177 cases and 82 (46%) were lymph node-negative (LN-) and 73 (41%) were lymph node-positive (LN+). Patients were treated for a mean of 65 months (range 1-169 months). RESULTS: 9 of 71 (13%) cases of lobular cancer featured HER-2/neu gene amplification, whereas 51 (48%) of 106 cases of ductal cancer showed amplification (P < 0.0001). On univariate analysis of combined lobular and ductal cases, HER-2/neu gene amplification detected by FISH predicted disease-related death (P < 0.0001). HER-2/neu gene amplification also predicted disease-related death in lobular cases alone (P = 0.003), LN+ lobular cases separately (P = 0.019), and LN- and LN+ ductal cases separately and alone (P < 0.0001). Multivariate analysis of the lobular group alone revealed that LN+ status (P = 0.015) and stage (P = 0.01) were independent predictors of disease-related death, and HER-2/neu gene amplification reached near significance (P = 0.086). In the ductal carcinoma group alone, HER-2/neu gene amplification (P = 0.03), lymph node status (P = 0.0001), tumor stage (P = 0.0001), and tumor grade (P = 0.044) were independent predictors of overall disease survival. CONCLUSIONS: HER-2/neu gene amplification detected by FISH was identified at a significantly lower rate in lobular compared with ductal breast cancer. HER-2/neu gene amplification when present in lobular breast cancer is a significant adverse prognostic factor.

The HER-2/neu oncogenic protein is a well-defined tumor antigen. HER-2/neu is a shared antigen among multiple tumor types. Patients with HER-2/neu protein-overexpressing breast, ovarian, non-small cell lung, colon, and prostate cancers have been shown to have a pre-existent immune response to HER-2/neu. No matter what the tumor type, endogenous immunity to HER-2/neu detected in cancer patients demonstrates two predominant characteristics. First, HER-2/neu-specific immune responses are found in only a minority of patients whose tumors overexpress HER-2/neu. Secondly, immunity, if detectable, is of low magnitude. These observations have led to the development of vaccine strategies designed to boost HER-2/neu immunity in a majority of patients. HER-2/neu is a non-mutated self-protein, therefore vaccines must be developed based on immunologic principles focused on circumventing tolerance, a primary mechanism of tumor immune escape. HER-2/neu-specific vaccines have been tested in human clinical trials. Early results demonstrate that significant levels of HER-2/neu immunity can be generated with active immunization. The T-cell immunity elicited is durable after vaccinations have ended. Furthermore, despite the generation of CD8(+) and CD4(+) T-cells responsive to HER-2/neu in a majority of patients, there is no evidence of autoimmunity directed against tissues that express basal levels of the protein. cancer vaccines targeting the HER-2/neu oncogenic protein may be useful adjuvants to standard therapy and aid in the prevention of relapse in patients whose tumors overexpress the protein. Furthermore, boosting HER-2/neu-specific T-cell frequencies via active immunization may allow the ex vivo expansion of HER-2/neu-specific T-cells for use in adoptive immunotherapy, a therapeutic strategy directed against the treatment of established disease.

AIMS: tumour tissue microarray allows the analysis of hundreds of tumour samples simultaneously on a single microscope slide. However, the extremely small tissue samples taken from the original tissue may not always be representative of the entire tumour. METHODS: The reliability of this new technology was investigated by analysing HER-2 oncogene amplification by fluorescence in situ hybridisation (FISH) from representative slides of the whole tumour and small tissue core biopsies from 29 invasive breast tumours. RESULTS: The tissue microarray method had high accuracy; in only one of 29 cases (3.4%; 95% confidence interval, 0% to 10%) were the results discordant with whole tumour analysis. CONCLUSION: tumour microarray is a highly reliable method for analysing HER-2 oncogene amplification by FISH in human breast tumours.

Existing prognostic algorithms for localized prostate cancer (PC) are hampered by poor validation for endpoints other than biochemical relapse such as clinical disease progression or survival. Therefore, the prognostic relevance of Her-2 (Her-2/neu, c-erbB2) protein expression in patients undergoing curative radiotherapy (RT) was compared to widely accepted prognostic factors such as pretreatment prostate-specific antigen (PSA) levels, biopsy Gleason score and T category of the primary tumor. Biopsies from 112 homogeneously treated patients with T1-4pN0M0 PC were examined by immunohistochemistry and 37% of cases showed membrane-bound Her-2 expression in more than 10% of cancer cells. No definite membrane staining was seen in normal prostate epithelium. With 25 patients dead of PC and a median follow-up of surviving patients of 71 months (range 48-144), the prognostic relevance of Her-2 expression was univariately associated with adverse outcome in terms of biochemical or clinical progression-free survival (B/C-PFS; p = 0.04), clinical progression-free survival (C-PFS; p = 0.02) and disease-specific survival (DSS; p = 0.02). In multivariate analysis, Her-2 expression, T category and Gleason score were independently associated with C-PFS, whereas only Her-2 expression and Gleason score were associated with DSS. Her-2 expression and Gleason score together discriminated 2 groups of patients with 5-year DSS of 95% and 79%, respectively (p < 0.001). Pretreatment PSA levels were associated only with B/C-PFS but not with C-PFS or DSS. Together the data show for the first time that expression of Her-2 is of prognostic relevance in localized PC undergoing RT and suggest that analysis for Her-2 may improve prognostic algorithms for clinically relevant endpoints other than biochemical relapse.

The cloning and functional characterization of a novel interferon regulatory factor (IRF), IRF-10, are described. IRF-10 is most closely related to IRF-4 but differs in both its constitutive and inducible expression. The expression of IRF-10 is inducible by interferons (IFNs) and by concanavalin A. In contrast to that of other IRFs, the inducible expression of IRF-10 is characterized by delayed kinetics and requires protein synthesis, suggesting a unique role in the later stages of an antiviral defense. Accordingly, IRF-10 is involved in the upregulation of two primary IFN-gamma target genes (major histocompatibility complex [MHC] class I and guanylate-binding protein) and interferes with the induction of the type I IFN target gene for 2 ,5 -oligo(A) synthetase. IRF-10 binds the interferon-stimulated response element site of the MHC class I promoter. In contrast to that of IRF-1, which has some of the same functional characteristics, the expression of IRF-10 is not cytotoxic for fibroblasts or B cells. The expression of IRF-10 is induced by the oncogene v-rel, the proto-oncogene c-rel, and IRF-4 in a tissue-specific manner. Moreover, v-Rel and IRF-4 synergistically cooperate in the induction of IRF-10 in fibroblasts. The level of IRF-10 induction in lymphoid cell lines by Rel proteins correlates with Rel transformation potential. These results suggest that IRF-10 plays a role in the late stages of an immune defense by regulating the expression some of the IFN-gamma target genes in the absence of a cytotoxic effect. Furthermore, IRF-10 expression is regulated, at least in part, by members of the Rel/NF-kappa B and IRF families.

Aberrant proliferation is an early-occurring event in vitro prior to tumorigenesis in vivo in the multistep process of carcinogenesis. Inhibition of aberrant proliferation therefore may represent a useful biomarker to evaluate the efficacy of chemopreventive agents. Retinoids have exhibited preventive efficacy in vitro and in vivo predominantly through the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs). Clinically relevant biochemical and cellular mechanistic endpoints for chemopreventive effects of retinoids should provide novel biomarkers. The present study was designed to examine the preventive efficacy of natural retinoids, all-trans-retinoic acid (ATRA) and 9-cis-retinoic acid (9cisRA), and to identify the possible mechanisms for their effects using the HER-2/neu oncogene expressing preneoplastic human mammary epithelial 184-B5/HER cells. Seven-day treatment with ATRA and 9cisRA exhibited a dose-dependent growth inhibition. Long-term (21 days) treatment with IC20 doses of 50 nM ATRA and 100 nM 9cisRA inhibited anchorage-dependent colony forming efficiency by about 75.4% (p<0.01) and 84.9% (p<0.01), respectively. Cell cycle analysis revealed that a 24-h treatment with IC90 doses of 2 microM ATRA and 3 microM 9cisRA accumulates cells in the G0/G1 phase and inhibit S and/or G2/M phase of the cell cycle. ATRA and 9cisRA induced an 11-fold (p=0.03) and a 9-fold (p=0.04) increase in subG0/G1 (apoptotic) population relative to the solvent control, respectively. ATRA and 9cisRA induced 77% (p=0.01) and 51% (p=0.02) decrease in tyrosine kinase immunoreactivity, respectively. Similarly, the two retinoids caused almost a 50% (p=0.01) down-regulation of Bcl-2 immunoreactivity. Western blot analysis revealed that ATRA induced an increase in RARbeta expression and a decrease in RARgamma expression, while 9cisRA down-regulated RXRalpha expression. These data demonstrate that ATRA and 9cisRA may inhibit HER-2/neu induced aberrant proliferation in part by retarding cell cycle progression, down-regulating HER-2/neu-mediated signal transduction and inducing Bcl-2-dependent apoptosis through a retinoid receptor-mediated mechanism.

c-erbB-2 oncoprotein (or p185) coded by c-erbB-2 oncogene can be extracted with detergent from cell membrane of breast tissue and breast tumor cell line. The ectodomain of p185 can be cleaved proteolytically from the transmembrane receptor and released into solution. In blood circulation, only the ectodomain can be found, whereas only p185 exists in the extracts of tissue and cell line. p185 can also be quantified in the fine-needle aspirate biopsies and the concentration of p185 from the biopsies of malignant breast tissue is much higher than that of the normal and benign tissue. Measuring the ectodomain of the c-erbB-2 oncoprotein not only is useful to identify breast cancer patient who will benefit from Herceptin treatment but also can be used to monitor patients during the treatment. Overexpression of p185 and the elevation of circulating ectodomain is usually associated with poor prognosis. Overexpression of p185 in breast cancer patients with positive estrogen receptor identifies a subgroup of patients who will not respond to the endocrine therapy. Activation of p185 appears to be an early event in tumorigenesis for some cancers. It is possible that the ectodomain could be used as an early tumor marker detecting benign disease.

HER-2 status has been used in breast carcinoma as a prognostic marker to predict drug response and to select patients for trastuzumab treatment. Since immunohistochemistry (IHC) is thought to be less reliable, HER-2 testing with FISH is preferred. The analysis of HER-2 is usually performed on formalin-fixed paraffin tissue sections obtained from surgery. The use of paraffin sections is very time consuming and labor intensive. The objectives of this study were to (1) develop a simple and quick FISH protocol using touch imprints of breast core needle biopsies, eliminating the deparaffinization and pretreatment; and (2) make the HER-2 status available at the presurgical multidisciplinary treatment planning conference. A total of 50 core samples of breast carcinoma were obtained from image-guided core needle biopsy. Both FISH and IHC data were available for 46 cases. Forty-four of 46 cases (95.7%) were consistent. Two IHC 2+ cases were nonamplified (ratios of 0.99 and 1.09). It is expected that, in the near future, additional molecular markers will be used before surgery when the overall treatment plan is being developed. We conclude that HER-2 gene analysis by FISH on breast touch imprints is easily done and is a useful and reliable technique.

Carcinogenesis by oncogenic Ras and Her-2 involves enhanced proliferation of epithelial cells in vivo. However, hyperproliferation induced by these oncogenes, or their downstream pathways in vitro has mainly been studied in cultured, fibroblastic cell lines. Here, we demonstrate that oncogenic Ha-Ras or constitutively active Her-2 cause increased proliferation and cyclin D1 upregulation in fully polarized, mammary epithelial cells (EpH4), if cultivated as organotypic structures in three-dimensional collagen/matrigel matrices. Under standard culture conditions, however, these oncogenes failed to induce hyperproliferation. Using both specific low molecular weight inhibitors and Ras-effector-specific mutants, we dissected signaling pathways downstream of oncogenic Ras (PI3K, Mek1/MAPK) with respect to (i) hyperproliferation in collagen gels and tumorigenesis in mice and (ii) epithelial/mesenchymal transition (EMT). We show that the Ras-activated PI3K pathway is required to induce rapid tumor growth and enhanced proliferation of EpH4 cells in collagen gels, but fails to cause EMT in vitro and in vivo. On the other hand, Ras-dependent activation of the Mek1/MAPK pathway in EpH4 cells (previously shown to cause EMT and metastasis) did not induce hyperproliferation in collagen gels and caused only slow tumor growth. Our data thus indicate that Ras-dependent signaling through the PI3K- and MAPK pathways fulfil distinct, but complementary functions during carcinogenesis.

Transgenic rats were created with overexpression of the Neu proto-oncogene in the mammary gland of both sexes, yet only males developed mammary cancer in an androgen-dependent fashion. Transgenic females only developed mammary cancer if treated with androgens. These tumors were positive for androgen receptor (AR), but negative for estrogen and progesterone receptors. Extensive analysis failed to detect mutations anywhere within the neu transgene from mammary carcinomas. Established mammary carcinomas eventually escaped their dependency on androgens. Transgenic long-term gonadectomized rats did not develop mammary cancer, but Neu overexpression stimulated the growth of their mammary glands. Our results suggest crosstalk between the Neu proto-oncogene and AR signaling pathways in the growth of both the normal and cancerous mammary epithelium.

It has been suggested that uPA in cancer cells is up regulated by the p 185 kD form of the HER-2/neu oncogene. We elected to see if the extra cellular domain of HER-2/neu, the p 105 fraction, which is found in the circulation, has any regulatory influence on uPA or uPAR in those patients with NSCLC Levels of uPA, uPAR and p 105 HER-2/neu were determined in blood from age-matched controls and patients with advanced NSCLC. In the patients with NSCLC, samples were obtained before and following treatment. A large increase in both uPA and uPAR compared to controls was seen in the patients prior to treatment. The uPAR level post-treatment decreased from pre-treatment values, which is favorable. There was a significant increase in uPA and a decrease in HER-2/neu in the post-treatment time frame. Additionally, correlation analysis of circulating uPAR, uPA and HER-2/neu against each other in both the controls and treatment groups indicated no relationship. It appears that circulating uPA and uPAR are elevated in NSCLC patients. The up-regulation of uPA by HER-2/neu seen in lung cancer cells in vitro is apparently lost in the blood in vivo as is evidenced by the lack of correlation between them which is also true for the receptor as well.

The high incidence of HER2 overexpression on the cell surface of breast cancer cells and the recognized prognostic and potentially predictive value of HER2 render this cell surface receptor a novel and important therapeutic target. Although immunohistochemistry (IHC; HercepTest) and fluorescence in situ hybridization (FISH; PathVysion and INFORM)-both approved by the Food and Drug Administration-have emerged as the most viable assays for evaluation of HER2 status in routine clinical practice, there is still no consensus on which is the best method for assessing HER2 status. Therefore, our specific objective was to establish a chromogenic in situ hybridization (CISH) assay for the detection of HER2 amplification on a cohort of 173 archival invasive breast carcinomas. Results were compared with HercepTest, which is the most frequently used method for detecting HER2 alteration. Additionally, HER2 gene copy number was investigated using differential PCR (dPCR) as a testing system. HER2 overexpression was found by IHC in 24.3%; HER2 amplification was found by CISH in 19.1% and by dPCR in 9.2% of the tumors. The overall concordance rate was 95.9% between CISH and IHC and 85.0% between dPCR and IHC. Kappa statistics revealed an excellent agreement between IHC and CISH (kappa = 0.878), but only a moderate agreement was found between IHC and dPCR (kappa = 0.482). Discrepant cases between CISH and HercepTest and ALL IHC-positive cases (+2 and +3), a total of 42 cases, were analyzed with the FISH PathVysion (Vysis) assay. Among 25 HercepTest-positive cases (score +3), 2 showed no gene amplification by FISH or CISH. Four of 13 tumors with weak HER2 overexpression (score +2) were negative with both FISH and CISH. Concordance between CISH and FISH was 100% for the 38 cases analyzed. The current study showed that CISH represents a practical and simple assay for evaluating HER2 gene amplification in archival material, offering a promising alternative to IHC or FISH for the routine diagnostic setting.

Because of the relatively low incidence of lobular breast carcinoma, there are very few studies on the molecular characteristics of this breast cancer. In an attempt to improve its characterization, we investigated in a large collection of invasive lobular carcinomas (ILCs) the status of markers known to be involved in the better-studied invasive ductal carcinomas (IDC). In the current study we disposed of 80 well-characterized ILC cases. Gene amplification of cyclin D1 (CCND1) and c-erbB2-encoding gene (ERBB2) and expression of their gene products were studied by differential polymerase chain reaction (PCR) and immunohistochemistry, respectively. A comprehensive point mutation study of the phosphatase and tensin homolog tumor suppressor gene (PTEN) was pursued by single strand conformation polymorphism (SSCP)/sequencing analysis. The CCND1 gene was rarely amplified in ILC in spite of showing overexpression of the protein in 41% of tumors. Hence, unlike IDC, increase in gene dosage did not account for the protein excess. PTEN mutations were detected in ILC (truncating mutations) in around 2% of the tumors. Unlike IDC, ILC did not display ERBB2 overexpression and expression of the transcription factor E2F1 correlated inversely with tumor grade. The observed discrepancy in the pattern of the human oncogenes CCND1 and ERBB2, which are involved in the process of carcinogenesis of ductal tumors, appears to suggest a different molecular basis for development and progression of ILC.

C-erbB-2 is a protooncogene that is overexpressed in various cancers, either due to its amplification and/or increased transcription, and has been associated with more aggressive disease and a poor clinical prognosis in 20-30% of patients with breast cancer. Besides the prognostic factors such as tumor size, tumor grade, lymph node status, etc., which are significant in the management of breast cancer, C-erbB-2 level might also serve as an additional factor. Immunohistochemistry is the most frequently used method to study the expression of C-erbB-2 in breast cancer. We have generated a panel of monoclonal antibodies against C-erbB-2 oncoprotein with a view to evaluate their application for the diagnosis and therapy of breast cancer. In the present study, a simple, quantitative sandwich ELISA has been developed that uses two monoclonal antibodies directed against the extracellular domain of C-erbB-2 product, designated as CIBCgp185 as the capture antibody and CIBCHER-2 as the detector antibody. C-erbB-2 protein, isolated from BT474 cells, a human breast carcinoma cell line with high expression of C-erbB-2 and purified by Concanavalin A-Sepharose 4B affinity chromatography and HPLC has been used to develop the ELISA procedure. Sera samples of 150 healthy women donors and of 300 breast cancer patients with different histological types of malignancies have been analysed. The control women had serum C-erbB-2 in the range of 4.0-13.2 ng/mL, whereas the 300 breast cancer patients studied had a range of 4.8-75.2 ng/mL with a cut off value of 13.8 ng/mL. Our study showed that 18.6% of breast cancer patients had elevated levels of circulating C-erbB-2. These results might suggest that the serum C-erbB-2 level can be used as a potential tumor marker for breast cancer and that the Sandwich ELISA procedure might serve as an excellent alternative to immunohistochemistry in the near future.

The c-erbB-2 gene and its products (also designated HER-2 and c-neu) encode for a 185-kd transmembrane glycoprotein with intracellular tyrosine kinase activity. c-erbB-2 belongs to the epidermal growth factor receptor family, of which there are four known members, and has molecular homology to the epidermal growth factor receptor. It seems that this family is critical in control of growth, differentiation, and mobility of many normal and transformed epithelial cell types. We have looked for overexpression of c-erbB-2 gene product in paraffin-embedded material from 230 cases of soft tissue sarcoma, in order to establish a possible new prognostic marker and a potentially new treatment option. In ALL the cases, irrespective of the sarcoma histological type, the immunostaining for erbB-2 was negative. Applications of erbB-2 for prognostication as well as the option of receptor targeting by trastuzumab monoclonal antibodies were aborted.

Our study attempts to determine the prognostic value of the quantitative measurement of the oncoprotein p185(Her-2/neu) in a group of patients with breast cancer and positive node involvement. In a series of 217 patients with breast cancer and positive nodes in whom the oncoprotein p185 was quantitatively determined by ELISA, we analyzed the clinico-pathological variables including age, menopausal status, tumor size, number of affected nodes, type and histology grade and the molecular variables such as the oestrogen and progesterone receptors (ER and PR, respectively), pS2 and Cathepsin D (CD). Using 260 fmol/mg protein as a cut-off point, 18% of the tumors presented as overexpressing p185. The p185 showed no relationship with any of the clinico-pathological variables studied except that its concentration was elevated in ductal and lobular histology types and in the moderate and poorly differentiated histology grades. With a median follow-up of 50 months (range 1-90), the univariate analysis of disease-free survival (DFS) and overall survival (OS) showed that the histology grade, tumor size, the number of infiltrated nodes, the p185 and the ER were the variables associated with the clinical course of the disease in the patients. In the multivariate analysis, however, only the tumor size, number of affected ganglia, the p185 and the ER remained associated with the clinical progression of the disease. The patients with p185 overexpression had a risk, not only of relapse but also death from the disease, of more than twice that of the patients who had normal p185 concentrations. When the p185 was divided into 3 categories based on +/-1 x SD above or below the mean, the patients with high and low p185 showed, in the univariate analysis, a similar relationship with DFS but not with OS. In the multivariate analysis, both with the DFS as with the OS, only a high p185 concentration retained its association with the clinical course of the disease in the patients. Our results suggest that by quantitatively determining (using ELISA) the p185 oncoprotein, groups of cancer patients of high risk could be better identified for more effective clinical management.

In the multistep progressive pathogenesis of human breast cancer, comedo ductal carcinoma in situ (DCIS) represents a preinvasive precursor lesion for therapy resistant invasive cancer. Human tissue derived cell culture models exhibiting molecular similarities to clinical DCIS facilitate an important preclinical mechanistic approach for evaluation of preventive efficacy of natural and synthetic chemopreventive compounds. Natural phytochemicals present in fresh fruits, vegetables and grain products are likely to offer protection against cancer. The clinical efficacy of these natural phytochemicals, however, depends on extrapolation, and is therefore equivocal. The present study determined whether the natural soy isoflavone genistein (GEN) inhibited aberrant proliferation in 184-B5/HER cells (a model for human comedo DCIS) and identified possible mechanisms responsible for its efficacy. Human reduction mammoplasty derived HER-2/neu oncogene expressing preneoplastic 184-B5/HER cells represented the experimental system. Flow cytometry and cellular epifluorescence based assays were utilized to quantitate the alterations in cell cycle progression, cellular apoptosis, and in the status of cell cycle regulatory and apoptosis-associated gene product expression. The 184-B5/HER cells exhibited specific immunofluorescence to p185HER, p53, EGFR, but not to ERalpha, thus resembling comedo DCIS. Treatment of 184-B5/HER cells with GEN resulted in a dose-dependent decrease in the viable cell population, increase in the G0/G1:S + G2/M ratio and enhancement of sub G0/G1 (apoptotic population). Exposure to the maximum cytostatic 10 microM dose of GEN down-regulated HER-2/neu mediated signal transduction as evidenced by a 73.9% decrease (p=0.001) in p185HER specific, and a 89.8% decrease (p=0.001) in phosphotyrosine specific immunofluorescence. The increase in G0/G1:S + G2/M ratio in response to the treatment with 10 microM GEN was associated with a 85.5% decrease (p=0.001) in immunoreactivity to PCNA and a 128.6% increase (p=0.004) in immunoreactivity to the cyclin dependent kinase inhibitor p16INK4. The induction of apoptosis by GEN was associated with a 52.8% decrease (p=0.001) in the immunoreactivity to antiapoptotic Bcl-2 and with a 195.9% (p=0.001) increase in the immunoreactivity to proapoptotic Bax. Thus, preventive efficacy of GEN in HER-2/neu+/ER- 184-B5/HER cells may be due to its ability to down-regulate HER-2/neu mediated signal transduction, increase the expression of the cyclin dependent kinase inhibitor p16INK4, and induce Bcl-2 dependent apoptosis. These data provide evidence that GEN may be a potential chemopreventive lead compound for human comedo DCIS. The 184-B5/HER cells, may therefore, provide a high throughput mechanistic bioassay to identify new chemopreventive agents for human breast cancer.

Amplification of the c-erbB-2 oncogene and protein overexpression are well-known in breast cancer and a basis for therapy with the monoclonal antibody trastuzumab, which binds to the receptor encoded by c-erbB-2. Regarding bladder carcinoma, several studies have examined c-erbB-2 expression, but their results are quite heterogeneous. In the present study, we evaluated the expression of this oncoprotein immunohistochemically in 203 muscle-invasive urothelial bladder carcinomas using the HercepTest. Additionally, 42 cases were studied for gene amplification by fluorescence in situ hybridization (FISH) using the PathVysion kit. Follow-up was known in 147 patients. The results were compared with pathologic characteristics and disease-related survival. Immunohistochemical c-erbB-2 overexpression was observed in 37% of the tumors (76/203). However, only 5% (2/42) showed amplification of the oncogene, indicating that predominantly other mechanisms than gene amplification may cause protein overexpression in bladder cancer. C-erbB-2 protein overexpression was significantly associated with high tumor grade (p=0.004) and infiltrative growth pattern (p=0.0001), and tendentiously associated with the presence of lymph node metastases (p=0.077). Regarding tumor stage, sex and age, no significant correlation was registered. Kaplan-Meier curves showed a significantly worse disease-related survival for patients with c-erbB-2 overexpressing tumors (p=0.0346 by log-rank test). Multivariate analysis revealed that, besides nodal status (p=0.0001) and tumor stage (p=0.028), c-erbB-2 overexpression was an independent predictor of disease-related survival (p=0.030). Thus, our results suggest that immunohistochemical c-erbB-2 detection might represent an additional tool in determining bladder cancer prognosis. Clinical trials evaluating the efficacy of trastuzumab therapy in bladder cancer patients are warranted.

Assessment of HER2/neu oncogene has been used as both a prognostic and predictive marker for breast cancer. However, the choice of the best method to assess the status of HER2/neu oncogene in breast cancer tissue remains controversial. A variety of techniques are available to detect HER2/neu gene amplification and overexpression. Tissue-based detection methods by immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH) offers a clear advantage over other approaches. FISH is a costly and relatively difficult assay and yet appears to be a better predictor of response to Herceptin (Trastuzumab) therapy and patient outcome. IHC is less expensive and is easier to perform; however, it suffers from a high rate of false negativity and positivity as well as inter-observer variability among pathologists. Suggestions have been made to use IHC as a screening procedure followed by confirmation by FISH in selected cases. Considering the importance of an accurate assessment of HER2/neu oncogene in selecting therapy, a better alternative may be to use FISH as the primary testing for HER2/neu oncogene. Herceptin therapy is associated with several side effects and is expensive. Thus, in the long term, it may be more cost-effective to use the FISH procedure and reduce the possibility of under-treatment or over-treatment of breast cancer patients. In addition, assessment of HER2/neu oncogene on every newly diagnosed early breast carcinoma may not be necessary. Metastatic lesions, when they occur, can be sampled by fine needle aspiration biopsy or core needle biopsy for assessment of HER2/Neu status.

The pathogenesis of chronic pancreatitis remains controversial. According to the general opinion, chronic pancreatitis is a de novo disease with a silent but progressive restructure of the pancreas in response to environmental, nutritional or genetic factors. The necrosis-fibrosis sequence hypothesis, on the other hand, postulates that relapsing attacks of acute pancreatitis with subsequent development of fibrosis leads to chronic pancreatitis. Since in our previous studies the expression of two anti-ErbB2 growth factor receptor (ErbB2) antibodies was shown to discriminate between primary chronic pancreatitis, normal tissue, and secondary chronic pancreatitis caused by pancreatic cancer, we studied the ErbB2 expression in tissues obtained from acute, recurrent acute, and chronic pancreatitis to investigate a possible evolution of the ErbB2 expression pattern during the course of the disease. We subjected 14 normal pancreas, 15 chronic pancreatitis, and 12 acute pancreatitis (three with recurrent acute pancreatitis) specimens to immunohistochemical studies using polyclonal anti-ErbB2 antibodies from Santa Cruz and Dako. The immunoreactivity of islet cells in acute pancreatitis cases with the Santa Cruz antibody was less than that in normal pancreas in relation to the degree of tissue damage and fibrosis, and was negative in recurrent acute and chronic pancreatitis tissues. The Dako antibody, on the other hand, revealed a membrane staining of ductal and ductular cells only in chronic pancreatitis specimens and in some areas of recurrent acute pancreatitis. In conclusion, the similarities in the immunoreactivity of anti-ErbB2 antibodies in recurrent acute pancreatitis and chronic pancreatitis support the hypothesis that acute pancreatitis can be a forerunner of chronic pancreatitis.

Female transgenic FVB mice carrying breast cancer gene HER-2/neu were monthly injected with Vilon or Epithalon (1 microgram subcutaneously for 5 consecutive days) starting from the 2nd month of life. Epithalon markedly inhibited neoplasm development: the maximum size of breast adenocarcinomas was 33% lower than in the control (p < 0.05). The intensity of HER-2/neu mRNA expression in breast tumors of Epithalon-treated mice was 3.7 times lower than in control animals. These results indicate that Epithalon inhibits breast tumor development in transgenic mice, which is probably related to suppression of HER-2/neu expression.

Monoclonal antibody CIBCgp185 of IgG2a isotype has been generated against C-erbB-2 oncoprotein using BT474 breast carcinoma cell line as immunogen. Earlier studies have revealed that this MAb has potential application as diagnostic tool in the detection of breast cancers overexpressing C-erbB-2. In the present study, the reactivity pattern of this MAb was studied on frozen sections of 28 malignant and 15 normal breast tissues and on cultured mammary tumor cell lines by indirect immunofluorescent staining. Results indicated that gp185C-erbB-2 was overexpressed in 6 malignant specimens, indicating correlation with immunohistochemical analysis studied previously. These results indicate that immunofluorescence might also be used to study C-erbB-2 overexpression in breast cancers and could serve as a confirmatory test for IHC. However, further studies with large number of cases are needed to confirm these results.

It is known that the HER2/neu proto-oncogene is associated with a wide variety of human cancers and considered to be an attractive target for developing anti-cancer agents. We report here for the first time that the Epstein-Barr virus nuclear antigen-1 (EBNA1) suppresses the HER2/neu oncogene expression at the transcriptional level. Recombinant clones of EBNA1 were subcloned and stably transfected into HER2/neu-overexpressing human ovarian cancer SKOV3.ip1 cells. These EBNA1-containing clones down-regulated the endogenous production of p185(HER2/neu). In addition, the EBNA1-expressing stable transfectants showed reduced growth rate, low soft agarose colony-forming ability and tumorigenic potential as compared with the parental line. These data suggest that EBNA1 may act as a transforming suppressor of the HER2/neu oncogene.

Bcl-X(L) is essential for the survival and normal maturation of erythroid cells, especially at the late stage of erythroid differentiation. It remains unclear whether Bcl-X(L) serves only as a survival factor for erythroid cells or if it can induce a signal for differentiation. We have previously shown that dimethyl sulfoxide (DMSO) induction of erythroid differentiation in murine erythroleukemia (MEL) cells correlates with delay of apoptosis and specific induction of Bcl-X(L). In this study, we investigate the contribution of Bcl-2 and Bcl-X(L) to survival and erythroid differentiation by generating stable MEL transfectants expressing these antiapoptotic regulators. Overexpression of Bcl-2 completely prevented apoptosis of MEL cells before and after DMSO induction, whereas overexpression of Bcl-X(L) only delayed it. Overexpression of Bcl-2 or Bcl-X(L) neither induced spontaneous erythroid differentiation nor accelerated DMSO-induced differentiation. Inhibition of Bcl-X(L) by antisense transcripts accelerated apoptosis in DMSO-treated MEL cells and blocked the synthesis of hemoglobin without altering the growth arrest associated with terminal erythroid differentiation. An antisense oligonucleotide to Bcl-X(L) did not induce apoptosis in MEL cells overexpressing Bcl-2 but greatly decreased their hemoglobin synthesis when treated with DMSO, suggesting that Bcl-X(L) is necessary for erythroid differentiation independently of its antiapoptotic function. Importantly, Bcl-X(L) antisense transcripts prevented heme synthesis but not globin mRNA induction in DMSO-treated MEL cells. Furthermore, inhibition of hemoglobin synthesis by Bcl-X(L) antisense was reversed by addition of exogenous hemin. Finally, Bcl-X(L) localized to mitochondria during MEL erythroid differentiation, suggesting that it may mediate a critical mitochondrial transport function related to heme biosynthesis.

OBJECTIVE: To evaluate circulating HER-2/neu in cervical cancer patients prior to and following treatment. METHODS: Controls, and patients with either cervical dysplasia or cancer taken from an active gynecologic oncology service were evaluated for the expression of HER-2/neu in serum by ELISA before and following surgery, radiation, chemotherapy or combinations thereof. The resulant data was then evaluated for significance by either ANOVA or non-parametric testing. RESULTS: Mean differences were noted for patients with cervical cancer compared to controls. Patients with a good response to the chemotherapy indicated an increase in the serum oncogene, while those not responding either had no marked change or decreased the level of serum HER-2/neu. CONCLUSIONS: As serum HER-2/neu is a membrane bound portion of the intact molecule, these results suggest that due to the induction of cell death and breakdown, the liberation of this fraction (increased levels in the serum), is a viable indicator of response to treatment in some patients. A more detailed examination of this possibility along with expanded correlation with tissue expression is required.

A single mutation within the transmembrane region of the Neu receptor (Val664-->Glu) is known to enhance tyrosine kinase activity, by promoting receptor dimerization. In order to gain insight into potential structural changes that arise as a result of the mutation, peptides corresponding to the complete transmembrane domain of proto-oncogenic and mutant forms of Neu have been studied by 1H nuclear magnetic resonance in the solvent trifluoroethanol (TFE). The chemical shifts are similar for both forms of the peptide, with the exception of amide residues close to the mutation site. Both peptides adopt a helical conformation, with a distinct bend one turn downstream of the mutation site. This deformation gives rise to several nuclear Overhauser effects, the majority of which were detected in both peptides, that are atypical for a straight canonical alpha-helix. Our data in this solvent do not support a conformational change in the transmembrane domain of monomeric Neu as a result of the mutation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicates that proto-oncogenic Neu peptides have a higher propensity to oligomerize in the solvent TFE than the Glu664 oncogenic form.

Determination of HER-2/neu oncogene amplification has become clinically important in the present management of breast cancer and may have important applications in other areas of clinical oncology and scientific research. In situ hybridization is an extremely accurate and sensitive technique for assessing amplification of HER-2/neu. A new method using a chromogen-labeled probe offers numerous advantages, including the ability to view the morphologic features of the cells of interest using a light microscope, which can be found in every laboratory. We used both techniques to assay 31 cases of infiltrating breast carcinoma; assays were performed in laboratories at 2 institutions. Identical results for both methods were found in 26 cases (10 amplified, 16 nonamplified). One case was misinterpreted as overexpressed by chromogenic in situ hybridization (CISH) because of background precipitate. In 4 cases, CISH suggested low-level amplification. Three of these cases subsequently were found to have chromosome 17 polysomy. In the remaining case, the initial section chosen was suboptimal, showing weak signals by both methods. If a probe for chromosome 17 (now available for CISH) is used in cases of questionable HER-2/neu amplification, CISH seems to be as accurate and more practical than FISH.

A comparative study was undertaken between cancer of the uterine cervix (n = 50) and female breast cancer (n = 50) with reference to the expression of c-erbB-2 oncoprotein (HER-2/neu) and that of epidermal growth factor receptor (EGF-R), both being highly homologous structurally. expressions of EGF-R and c-erbB-2 oncoprotein were viewed in breast and cervical cancer tissues by immunochemical staining. Cervical cancer cases showed much higher expression of EGF-R which also revealed significant association with the expression of c-erbB-2 oncoprotein and tumour grading. Among breast cancer cases, over-expression of EGF-R correlated significantly with metastasis of lymph node; and expression of c-erbB-2 oncoprotein showed a significant relationship with histological grading of the tumour. Moreover, an association was noticed between the tumour grade and the concomitant immuno positive expression of EGF-R and c-erbB-2. Our study revealed an existence of a conflicting pattern in the expression of EGF-R and c-erbB-2 oncoprotein between carcinomas of the breast and uterine cervix.

The amplification and/or overexpression of the HER-2/neu oncogene and its encoded receptor protein are increasingly used for prognostication and prediction of therapeutic response to Herceptin in breast cancer. However, large-scale examination of archival tumor blocks by immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) is prohibitively laborious and technically challenging. The tissue microarray (TMA) technique enables hundreds of tumors to be studied simultaneously in a single experiment. To evaluate the HER-2/neu status of a selection of the breast tumors in our tumor bank, we constructed a TMA from 97 breast tumors, with a single 0.6-mm core per specimen. HER-2/neu gene amplification by FISH was found in 20 of the 87 interpretable cases (23%): in 14 of 14 IHC 3+ cases (100%), 5 of 8 IHC 2+ cases (62.5%) and 1 of 65 IHC 0/1+ cases (1.5%). Three of the 67 cases with no evidence of HER-2/neu gene amplification by FISH were moderately positive (2+) by IHC. A close relationship was observed between these 2 assays as applied to the TMA (95.4% concordance: 95% CI, -2.2% to 6.8%; P <0.0001), and both HER-2/neu gene amplification and protein overexpression were strongly associated with tumor grade, estrogen receptor status, and progesterone receptor status. Gene amplification was found in most of the tumors with high-level overexpression (IHC 3+) and not in the unequivocal IHC-negative cases. Complementary analysis by IHC and FISH are, however, recommended for tumors graded as 2+ by IHC, the group with the most result discrepancy. Hum Pathol 34:362-368.

OBJECTIVE: To investigate the deletion of p53 gene and amplification of HER-2 oncogene at chromosome 17 in primary hepatocellular carcinoma (HCC) and the clinical significance. METHODS: Interphase dual fluorescence in situ hybridization (FISH) was applied to detect the ratio of the number of p53 gene copy or HER-2 oncogene copy to that of chromosome 17 copy, to determine the p53 gene deletion and HER-2 oncogene amplification in nuclei prepared from 42 surgical specimens of HCC. Statistical analysis for their clinical significance was performed. RESULTS: Loss of p53 gene and amplification of HER-2 oncogene were detected in 27 (64.3%) and 9 (21.4%) of the 42 HCC respectively including 4 cases with low and 5 with high copy amplification. Six (14.3%) of 42 HCC showed simultaneously p53 gene deletion and HER-2 oncogene amplification. 61.9% (26/42) of HCC were polysomy 17, which correlated positively with p53 gene deletion (chi(2) = 12.286, P < 0.001). No close correlation between p53 gene loss and HER-2 oncogene amplification was found (chi(2) = 0.00, P = 1.00). Loss of p53 gene was related to the serum alpha-fetoprotein (AFP) level and the tumor size (P < 0.05). The postoperative 2-year survival rate (18.5%) of HCC patients with p53 gene deletion was significantly lower than postoperative 2-year survival rate (60.0%) of those without p53 gene loss (chi(2) = 7.467, P = 0.006). Meanwhile, HER-2 oncogene amplification showed a tendency of correlation with the tumor size (chi(2) = 2.973, P = 0.085), and the postoperative 2-year survival rate (0/9) of HCC patients with HER-2 oncogene amplification was significantly lower than those (42.4%) without HER-2 oncogene amplification (chi(2) = 3.977, P = 0.046). CONCLUSION: There were a high frequency of p53 gene deletion and a low frequency of HER-2 oncogene amplification in primary HCC, which might be involved in initiation and development of a subset of primary HCC.

INTRODUCTION: The human epidermal growth factor receptor ( her-2/ neu) protooncogene encodes a membrane tyrosine kinase with homology to the epidermal growth factor receptor (EGFR). Amplification and protein overexpression have been identified in various solid tumors and a significant association with poor clinical outcome was reported. This investigation was performed to assess the frequency of her-2/ neu overexpression and to compare these results with clinical outcome in OSCC. MATERIAL AND METHODS: Archival biopsy specimens from 97 untreated OSCCs were evaluated using a polyclonal antibody A0485 (Dako). Only membrane staining intensity and pattern were evaluated according to the guidelines of the clinical trial assay recommendations (0-3+) for breast carcinoma. Score 0 and 1+ were interpreted as negative for HER-2/NEU protein overexpression and 2+ and 3+ as positive. FISH analysis with directly labeled probes for her-2/ neu and chromosome 17 was performed on the same specimens. The ratio between her-2/ neu and chromosome 17 signals was calculated after selection of 20-40 non-overlapping tumor cells. The tumor was considered amplified if the ratio was above 2. RESULTS: In 11 out of 97 biopsies (11.3%) membranous overexpression (score 2+ and 3+) of her-2/ neu was shown by immunohistochemistry. FISH analysis in 42 cases revealed amplification in 14 cases. Concordance between immunohistochemistry and FISH was found in 86%. Clinical-pathological data as well as survival revealed no correlation with her-2/ neu status. DISCUSSION: In spite of missing correlation between survival and her-2/ neu overexpression in our study, the predictive value of the her-2/ neu protooncogene in adjuvant therapy in OSCC needs further investigation.

AIMS: To study HER2 oncogene amplification and over-expression in skin samples of 23 patients with extramammary Paget s disease (EMP). EMP is a rare intra-epidermal adenocarcinoma, which has been reported to over-express the HER2 oncoprotein. METHODS AND RESULTS: HER2 gene amplification, detected by chromogenic in-situ hybridization, was found in 43% (10/23) of the lesions. HER2 protein over-expression (3+ immunostaining intensity) was found in 12 tumours (52%), including ALL 10 tumours with gene amplification. Two tumours showed low-level (2+) HER2 immunostaining. Mammary Paget s lesions, which were used as controls, showed HER2 amplification and over-expression in ALL 10 cases studied. CONCLUSIONS: These results indicate that HER-2 protein over-expression in EMP is common and due exclusively to gene amplification. They open up the possibility of HER2-targetted immunotherapy for patients with HER2+ disease.

The development of cancer vaccines requires approaches to induce expansion and functional differentiation of tumor antigen-specific cytotoxic T lymphocyte (CTL) effectors which posses cytolytic capability and produce cytokines. Efficient induction of such cells is hindered by the poor immunogenicity of tumor antigens and by the poor transduction efficiency of dendritic cells (DCs) with current nonreplicating vectors. We have investigated the use of influenza A virus, a potent viral inducer of CTLs, as a vector expressing the immunodominant HER-2 CTL epitope KIF (E75). For this purpose, an attenuated influenza A/PR8/34 virus with a truncated nonstructural (NS1) gene was generated containing the E75 epitope in its neuraminidase protein (KIF-NS virus). Stimulation of peripheral blood mononuclear cells from healthy donors and of tumor-associated lymphocytes from ovarian and breast cancer patients with DCs infected with KIF-NS virus (KIF-NS DC) induced CTLs that specifically recognized the peptide KIF and HER-2-expressing tumors in cytotoxicity assays and secreted gamma interferon (IFN-gamma) and interleukin-2 at recall with peptide. Priming with KIF-NS DCs increased the number of E75(+) CD45RO(+) cells by more than 10-fold compared to nonstimulated cells. In addition, KIF-NS virus induced high levels of IFN-alpha in DCs. This is the first report demonstrating induction of human epitope-specific CTLs against a tumor-associated antigen with a live attenuated recombinant influenza virus vector. Such vectors may provide a novel approach for tumor antigen delivery, lymphocyte activation, and differentiation in human cancer vaccine development.

Using flow cytometry (FCM), we have investigated both the DNA content (stained with propidium iodide) and HER-2/neu oncogene expression (revealed by means of an anti-HER-2/neu monoclonal antibody) in neoplastic and non-neoplastic kidney samples from 20 patients with renal cell carcinoma. ALL the non-neoplastic samples and 15/20 (75%) renal cell cancers showed diploid modal DNA content while the remaining 5 neoplastic sample (25%) showed both diploid and hyperdiploid cell populations. In normal kidney the level of HER-2/neu oncoprotein was low (median fluorescence values in arbitrary units = 7.5 AU, range: 4-10 AU). In diploid renal cancers the level of HER-2/neu was slightly increased (median fluorescence values = 20 AU, range: 9.5-30 AU) (p < .005). The relationship of HER-2/neu expression to the cell cycle in these tumor samples is not clear since most of the cells express the antigen in ALL phases of the cell cycle. On the other hand, there is an association between HER-2/neu expression and abnormal DNA content suggesting that aneuploid pattern may be biologically related to overexpression of the HER-2/neu gene.

The occurrence of epithelial membrane antigen (EMA), low molecular weight cytokeratin (CK) and erbB-2 oncoprotein was investigated in twenty-eight cases of Paget s disease of the nipple (PD) to determine their diagnostic usefulness. The ABC technique with monoclonal antibodies was used on formalin-fixed, paraffin-embedded tissue. The Paget s cells showed positive immunoreactivity for ALL three antigens investigated in a high percentage of PD. Immunoreactivity for CK and erbB-2 oncoprotein was restricted to the Paget s cells, whereas EMA in some cases also stained the adjacent keratinocytes. Since CK and/or erbB-2 oncoprotein occurred in 93% of the cases, we conclude that demonstration of both antigens is useful in the diagnosis of PD. ErbB-2 oncoprotein was also found to be expressed in a high percentage of the underlying intraductal and invasive carcinomas.

INTRODUCTION: Tyrosine kinase signal transduction pathways are a focus of interest for therapeutic interventions. The oncoprotein HER-2/neu shows tyrosine kinase activity leading to phosphorylation and activation of numerous second-messenger systems. One target of phosphorylation processes is assumed to be the tumor type M2 isoenzyme of pyruvate kinase (TuM2-PK) which has been shown to be elevated in metastatic breast cancer. MATERIALS AND METHODS: We measured the plasma levels of HER-2/neu, TuM2-PK and tyrosine-phosphorylated TuM2-PK (p-TuM2-PK) in 69 patients (pts) with breast cancer and correlated these parameters to each other and to the classical tumor marker CA 27.29. The samples were measured with ELISA assays while CA 27.29 was determined with an automated chemiluminescence assay. For analysis, we formed 5 subgroups according to the plasma HER-2/neu levels (group 1: < 15 ng/ml, n = 28; group 2: 15 < or = x < 50 ng/ml, n = 21; group 3: 50 < or = x < 100 ng/ml, n = 9; group 4: 100 < or = x < 500 ng/ml, n = 7; group 5: > or = 500 ng/ml, n = 4). RESULTS: From the HER-2/neu group 1 to group 5, there was a statistically significant increase of CA 27.29 from 35.8 U/ml to 1095.8 U/ml (p < 0.001). There was also a trend for increasing TuM2-PK levels with increasing HER-2/neu levels (p = 0.126). From the lowest extinction (0.088) to the highest extinction result (2.167) of p-TuM2-PK we found a 25-fold increase, which was reproducible in spiking and dilution experiments proving that TuM2-PK is phosphorylated at tyrosine residues to a certain extent. However, there was no correlation between plasma HER-2/neu and p-TuM2-PK levels. CONCLUSION: TuM2-PK is phosphorylated at tyrosine residues in breast cancer patients. Using the shed antigen of HER-2/neu in plasma as a surrogate marker, we did not find any evidence that this phosphorylation is initiated by the oncoprotein HER-2/neu.

The HER-2/neu oncogene codes a protein of the family of epidermal growth factor receptors. The extracellular domain has a MW from 95-105 kDa and is shed into the blood. In some patients with malignant tumors there is a high expression of HER-2/neu connected with high levels of HER-2/neu protein in the serum. High concentrations signal aggressive growth, bad prognosis and shorter survival. The reference range lies between 4.0 and 14.0 ng/ml with a mean of 9.0 ng/ml. There is a significant difference of values between patients with and without metastases, but not between healthy people and patients without metastases. The advantage of this parameter lies in the early diagnosis of recurrence in the therapy of metastasizing breast carcinomas especially on treatment with Herceptin.

tumor markers were prospectively (CEA and CA 15.3) or retrospectively (c-erbB-2) studied in the sera of 503 untreated patients with breast cancer diagnosed from 1988 to 2001. Abnormal c-erbB-2 levels (> 15 U/ml) were found in 7%, CEA in 12% and CA 15.3 in 13% of the 503 patients. C-erbB-2 serum levels were only related to c-erbB-2 in tissue, with significantly higher concentrations in patients with positivity in tissue. ALL the tumor markers (c-erbB-2 only in patients with positivity in tissue) were correlated with tumor size, TNM and nodal involvement. CEA was also related to menopausal status, c-erbB-2 overexpression in tissue and ER. Univariate analysis (mean follow-up 8 years) showed that CEA and CA 15.3 were prognostic factors with significantly shorter disease-free survival (DFS) and overall survival (OS) in patients with pretreatment tumor marker positivity. Multivariate analysis in DFS and in OS showed that nodal involvement CEA and ER but not tumor size, menopausal status, histological grade, histology, CA 15.3, c-erbB-2, PgR, adjuvant treatment, p53 (345 patients) or c-erbB-2 in tissue are independent prognostic factors. In summary, tumor markers are a useful, inexpensive and reproducible tool for prognosis in breast cancer.

Breast and ovarian cancers are the leading cause of death for women in many areas in the world including the United States. Overexpression of the HER-2/neu gene (also known as c-erbB2) is a frequent event in about 30% of breast as well as ovarian cancers. The overall survival rates of breast and ovarian cancer patients whose tumors overexpress HER-2/neu are significantly lower than those of patients whose tumors do not overexpress HER-2/neu. Overexpression of HER-2/neu leads to elevated tumorigenicity, enhanced metastatic potential, increased resistance to TNF-alpha-induced apoptosis and resistance to treatments such as paclitaxel and tamoxifen. Down-regulation of the HER-2/neu oncogene causes suppression of the cell-transforming phenotype induced by the oncogene. For example, downregulation of the HER-2/neu gene expression by E1A significantly mitigated tumorigenic activity of human breast and ovarian cancer cells in nude mice. These results strongly imply that HER-2/neu mediated cell transformation may be inhibited by transcriptional repressors that target the promoter of the oncogene. In addition to E1A, we recently identified the ets transcription factor PEA3 as a potential HER-2/neu gene inhibitor. PEA3 binds directly to this consensus binding motif and suppresses the HER-2/neu gene promoter activity. Downregulation of HER-2/neu expression led to inhibition of cell transformation and proliferation in vitro. In a preclinical gene therapy setting, in which the PEA3 gene tumor delivery was facilitated by a cationic liposome DC-Chol, blocked HER-2/neu overexpression by PEA3 resulted in prolonged survival of treated animals. These studies demonstrate a promising approach to cancer gene therapy using transcriptional repressors to target expression of oncogenes such as HER-2/neu.

Both epidermal growth factor receptor (EGFr) and the oncogene product of c-erbB2 have been shown to be expressed by human malignancies, and in some cases to relate to clinical outcomes. This study investigates the correlation between the presence of these receptor proteins and known prognostic indicators of colorectal cancer. Indirect immunoperoxidase staining of 32 freshly frozen surgical specimens revealed an overall expression of EGFr and c-erbB2 of 43% and 38%, respectively. A significantly higher rate of EGFr expression was found in tumours of more advanced stage (Dukes C and D), poor differentiation and those exhibiting vascular and lymphatic invasion. The presence of the c-erbB2 protein did not correlate with any of these variables. expression of these molecules appeared to be independent and positive staining for both receptors occurred in only 19% of cases. EGFr may play a future role as a prognostic tool in colorectal cancer.

To investigate HER-2/neu oncoprotein immunoreactivity, monoclonal antibody TA1 immunohistochemical examination of flash-frozen radical prostatectomy specimens was performed (n = 35). ALL prostatic specimens contained benign prostatic hyperplasia (BPH) and/or prostatic intraepithelial neoplasia (PIN), as well as prostatic carcinoma (CaP). HER-2/neu oncoprotein immunoreactivity in BPH tissues was not significantly different than that for the PIN basal cell layer (P = 0.10) or for the PIN luminal cells (P = 0.17). There was significantly more HER-2/neu oncoprotein immunoreactivity in BPH than in areas of CaP (P < 0.001). There was no significant difference in the amount of immunoreactivity present in PIN basal cells when compared to the PIN luminal cells (P = 0.49). Both the PIN basal cells and luminal cells stained for the HER-2/neu oncoprotein to a higher degree than cells in the CaP areas (P < 0.001 in both cases). HER-2/neu oncoprotein immunoreactivity is present at a significantly higher degree in BPH and PIN than in malignant prostatic epithelium.

The objective of the present study was to evaluate the correlation between HER-2 gene amplification and HER-2 protein overexpression in endometrial carcinoma using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). We also analyzed chromosome 17 aneusomy and the association between these biological parameters and conventional clinicopathological variables. FISH analysis was performed on 73 selected paraffin-embedded sections from endometrial carcinomas which previously had HER-2 status determined immunohistochemically using monoclonal antibodies (MoAb) 300G9 and CB11. Using a ratio of more than two oncogene signals/centromere to indicate amplification, a total of 42 out of the 73 endometrial tumors included in this study resulted positive by FISH where as protein overexpression was identified in 29 out of 73 with a concordance rate of 74.3%. However, when the mean signals/centromere per nucleus increased (ratio > 4 < or = 5) a higher concordance between the two assays was seen (p = 0.007). In addition, HER-2 amplification was significantly correlated with tumor stage (p = 0.021) and myometrial invasion (p = 0.010), whereas chromosome 17 polisomy showed a positive correlation only with myometrial invasion (p = 0.004) No significant correlation was found between HER-2 gene amplification, chromosome 17 aneusomy and patient outcome. Nevertheless, the probability of a 5 year overall survival decreased from 70% to 43%, respectively, for ratio > 2 < or = 4 and ratio > 4 < or = 5 when we grouped the amplified cases on the basis of HER-2:CEP17 ratio. In conclusion, molecular characteristics provide objective data that may be useful in predicting prognosis in patients with endometrial cancer.

BACKGROUND: This study investigated the role of nuclear factor-kappa B (NF-kappaB) activity in human breast cancer with overexpression of HER-2/neu oncoprotein, as well as its role on expression of different histological grades of cancer cells taken from Taiwanese breast cancer patients. MATERIALS AND METHODS: Specimens were collected from 82 female breast cancer patients. The HER-2/neu oncoprotein was measured by immunohistochemistry. NF-kappaB activity expression was assessed by the electrophoretic mobility shift assay, and confirmed by the supershift technique using anti-P65 antibody in both breast cancer tissue and the adjacent normal tissue. The histological grades were measured by Modified Bloom-Richardson Grading Scheme. RESULTS: Of the 82 cancer specimens, 81 (98.7%) showed higher or equal expressions of NF-kappaB activity when compared to the adjacent normal tissue. Fifty-five cases (67.1%) had higher levels of NF-kappaB activity in the cancerous tissue than in the adjacent normal tissue (p<0.005). With regard to tumor size, steroid receptors, stages, histological types, and node status, there were no statistically significant differences in NF-kappaB activity between cancerous tissues and adjacent normal tissues. However, significantly higher expressions of NF-kappaB activity were seen in those cases with positive HER2/neu oncoprotein, poorly differentiated histological grades, high nuclear pleomorphisms, and high mitotic counts (p<0.05). Positive HER-2/neu overexpression of oncoprotein had higher NF-kappaB activity (86%) than negative overexpression (60%) (p<0.05). It has been shown that the NF-kappaB activity increases in the HER-2/neu oncoprotein overexpression in human breast cancer. CONCLUSION: Overexpression of HER-2/neu gene could induce NF-kappaB activity in human breast cancer cells, as has been confirmed in other research on cell lines.

Amplification and/or overexpression of HER2/neu have been documented in many types of epithelial tumor and recently has been reported in sarcomas, particularly in osteosarcomas. But the role of HER2/neu alterations in soft tissue tumors remains poorly understood. Thus the present study investigates the expression of HER2/neu in 13 patients with synovial sarcoma (SS). In this study, HER2/neu mRNA levels were measured in frozen tissue samples using a real-time reverse transcription-polymerase chain reaction assay; protein expression was assessed by immunohistochemistry using an anti-HER2/neu polyclonal antibody. Six normal skeletal muscle specimens were used to establish basal levels of HER2/neu mRNA. HER2/neu transcripts were detected in ALL normal tissues and SSs. Four of 13 sarcomas (31%) demonstrated HER2/neu mRNA levels above the mean value, whereas 3 tumors (23%) displayed HER2/neu protein overexpression. Both membranous and cytoplasmic patterns of immunostaining were observed, and a strong correlation was found between protein expression and mRNA level (P = 0.01). Increased HER2/neu mRNA levels were significantly associated with a lower risk of developing recurrences (P = 0.02). Moreover, none of the patients with HER2/neu overexpression developed metastasis. Our data demonstrate that HER2/neu is expressed in SSs and that both membrane and cytoplasmic HER2/neu expression correlate with mRNA levels. Our results show that the presence of increased levels of HER2/neu in SSs is associated with a more favorable clinical course. Further studies are needed to assess the role of this oncogene in SSs and to evaluate the application of inhibitory humanized monoclonal antibodies in the treatment regimens for this malignancy.

Molecular dynamics simulations of an atomic model of the transmembrane domain of the oncogenic ErbB2 receptor dimer embedded in an explicit dimyristoylphosphatidylcholine (DMPC) bilayer were performed for more than 4 ns. The oncogenic Glu mutation in the membrane spanning segment plays a major role in tyrosine kinase activity and receptor dimerization, and is thought to be partly responsible for the structure of the transmembrane domain of the active receptor. MD results show that the interactions between the two transmembrane helices are characteristic of a left-handed packing as previously demonstrated from in vacuo simulations. Moreover, MD results reveal the absence of persistent hydrogen bonds between the Glu side chains in a membrane environment, which raise the question of the ability for Glu alone to stabilize the TM domain of the ErbB2 receptor. Interestingly the formation of the alpha-pi motif in the two ErbB2 transmembrane helices confirms the concept of intrinsic sequence-induced conformational flexibility. From a careful analysis of our MD results, we suggest that the left-handed helix-helix packing could be the key to correctly orient the intracellular domain of the activated receptor dimer. The prediction of such interactions from computer simulations represents a new step towards the understanding of signaling mechanisms.

The HER2/c-ErbB-2 proto-oncogene is overexpressed in 25-30% of human breast cancers. We previously reported the c-ErbB-2 transcript in mononuclear cells (MNC) from bone marrow (BM), peripheral blood (PB), and mobilized PB (MPB). Here, we describe extensively the expression pattern of c-ErbB-2 mRNA and protein in normal adult hematopoietic tissue and cord blood (CB)-derived cells. Quantitative reverse transcriptase-polymerase chain reaction shows that the c-ErbB-2 transcript is expressed in hematopoietic cells at low levels if compared with normal epithelial and breast cancer cells. The c-ErbB-2 protein was detected predominantly in MNC from PB and CB by Western blot analysis. Flow cytometry revealed that CD15+, CD14+, and glycophorin A+ subpopulations express c-ErbB-2 protein, whereas lymphocytes are c-ErbB-2-negative. The c-ErbB-2 expression is higher in CB MNC. More than 90% of BM- and MPB-derived CD34+ progenitors are c-ErbB-2-negative; by contrast, 5-40% of CB-derived CD34+ progenitors express c-ErbB-2. We found that c-ErbB-2 protein is up-regulated during cell-cycle recruitment of progenitor cells. Similarly, it increases in mature, hematopoietic proliferating cells. This study reports the first evidence that the c-ErbB-2 receptor is correlated to the proliferating state of hematopoietic cells. Studies in progress aim to clarify the role of c-ErbB-2 in regulation of this process in hematopoietic tissues.

BACKGROUND: This study prospectively examines the prognostic role of p53 oncoprotein (p53), Ki67-antigen (Ki67), tumor angiogenesis (MVD), epidermal growth factor receptor (EGFR), and HER2 receptor protein (HER2) expression in Chinese with undifferentiated nasopharyngeal carcinoma (NPC). METHODS: Seventy-eight Chinese were recruited from October 1995 to July 1997 at the Prince of Wales Hospital, Hong Kong. Pretreatment immunohistochemical preparations of the primary tumor were made, and clinical data were collected prospectively until October 30, 2000. The markers were correlated with overall survival (OS), disease-free survival (DFS), time to progression (TTP), and UICC stage. RESULTS: On univariate analysis, EGFR expression correlated with poorer OS (p =.0001), DFS (p =.01), shorter TTP (p =.0001), and advanced T stage (p =.036). Strong EGFR expression, when compared with weak or moderate, was associated with poorer OS (p =.04) and shorter TTP in a subgroup of patients with UICC stage III-IV disease. HER2 expression was associated with advanced UICC stage (p =.006). The presence of p53 expression correlated with poorer DFS (p =.01) and a trend toward shorter TTP (p =.06). No correlation was found with Ki67-antigen or MVD. On multivariate analysis, only EGFR expression was significantly linked to shorter OS and TTP. CONCLUSIONS: EGFR expression in undifferentiated NPC is associated with a poor clinical outcome. A prognostic role of p53 and HER2 expression is suggestive but not consistently defined in this study. The relatively high prevalence of positive staining for EGFR supports the use of molecular targeted therapy in this disease.

The occurrence of ERBB-2 (HER-2/NEU) oncogene amplification was studied in 203 DNA samples obtained from 175 cancer patients. Amplification of ERBB-2 oncogene was established in 14 out of 63 (22%) patients with breast cancer, 1 out of 23 cases of ovarian tumor, 1 out of 19 cases of large bowel cancer and 1 out of 27 patients with cancer of the thyroid. Patients with lung cancer (34), soft tissue sarcoma (6) and malignant melanoma (3) failed to reveal any changes in the above oncogene. A tendency was established for ERBB-2 oncogene amplification to be associated with lymph node involvement in female patients with breast cancer: amplification was observed in 9 out of 28 patients presenting with lymph node metastases and only in 5 out of 29 metastases-free cases. To summarize, ERBB-2 oncogene is fairly often activated in human tumors but a high occurrence of the gene amplification was observed in female patients with breast cancer only.

Many oncogenes encode proteins with a tyrosine kinase activity that appears to be directly involved in the process of transformation. Because these kinases are themselves activated for transformation by tyrosine phosphorylation, proteins which remove phosphate from tyrosine residues, protein tyrosine phosphatases (also termed phosphotyrosine phosphatases and protein phosphotyrosyl phosphatases), are intuitive candidate transformation suppressors. The human PTP1B gene, previously cloned in our laboratory and encoding the low molecular weight protein tyrosine phosphatase PTPase 1B, was introduced into NIH 3T3 cells. Subsequent transformation of these PTPase 1B-expressing cells by an oncogenic form of the human neu gene was suppressed relative to control NIH 3T3 cells. This suppression of transformation was observed in assays for focus formation, anchorage-independent growth, and tumorigenicity. tumorigenicity assays indicated a complex effect of PTPase 1B expression on transformation.

Amplification of the neu oncogene and overexpression of its product was found to be a potential marker for aggressive biological behavior in breast cancer. However, the expression of the neu oncoprotein in normal breast ducts and myoepithelial cells has also been demonstrated. Hence, we examined normal salivary gland tissue and 15 cases of pleomorphic adenoma for the expression of the neu oncoprotein by immunohistochemistry using two polyclonal antibodies and 12 cases for the amplification of the neu oncogene using slot blot hybridization. Immunohistochemistry in the normal salivary gland revealed positive staining of ALL ductal cells. In the pleomorphic adenomas ALL cellular elements stained to a variable degree. The positive staining was seen in the ductal cells, in the solid sheets, and in chondroid, myxoid, and metaplastic foci. The normal salivary gland and 11 of 12 cases of pleomorphic adenoma showed no increase in copy number of the neu oncogene, whereas one case showed threefold amplification. These results indicate that the neu oncoprotein is expressed but the neu copy number is not increased in normal salivary gland epithelium and in most pleomorphic adenomas. The threefold amplification of the gene in one case may indicate an aggressive biological behavior.

Activation of the c-erbB-2 oncogene can occur by amplification of c-erbB-2 DNA and by overproduction of c-erbB-2 mRNA and c-erbB-2 protein. Approximately 20 percent of breast carcinomas show evidence of c-erbB-2 activation, which correlates with a poor prognosis primarily in patients with metastasis to axillary lymph nodes. Studies that have attempted to correlate c-erbB-2 activation with other prognostic factors in breast carcinoma have reported conflicting conclusions. The pathologic and clinical significance of c-erbB-2 activation in other neoplasms is unclear and should be assessed by additional studies.

DNA content, proliferative activity (Ki-67 immuno-staining and S-phase fraction by flow cytometry), and neu-oncogene overexpression were studied in 135 patients with invasive breast carcinoma. Image analysis and flow cytometry of fresh tumors showed good correlation between the two methods and yielded 39% diploid tumors and 61% aneuploid tumors. Aneuploidy, including tetraploidy, was significantly related to the loss of estrogen (p = 0.0002) and progesterone (p = 0.03) receptors, high histologic (p = 0.014) and nuclear (p less than 0.0001) grades, and mitotic rate (p = 0.0001). Immunohistochemical evaluation of proliferation by staining with Ki-67 monoclonal antibody and of neu-oncogene protein overexpression was performed in fresh frozen tissue from 83 tumors. The Ki-67 score, quantitated by the CAS-200 image analyzer, correlated only moderately with S-phase fraction obtained by flow cytometry by linear regression analysis (r = 0.39, p less than 0.001). However, both of these proliferation markers correlated strongly with the mitotic rate (p less than 0.0001). Aneuploid and tetraploid tumors demonstrated higher Ki-67 scores and S-phase fractions than diploid tumors. Neu-oncogene protein overexpression was seen in 24 tumors (29%) overall and was much higher in aneuploid tumors (38%) and tetraploid tumors (50%) than in diploid tumors (7%). However, the concentration of neu-oncogene protein positive tumors in the tetraploid region reported by others was not observed. Neu-oncogene protein overexpression was also associated with higher Ki-67 scores (p = 0.016) and S-phase fractions (p = 0.037).(ABSTRACT TRUNCATED AT 250 WORDS)FAU - Lee, A K

To develop an efficient strategy for the targeting of anti-tumor effector cells, we prepared bispecific antibody (BsAb) containing anti-CD3 and an anti-c-erbB-2 proto-oncogene product. The prepared BsAb specifically reacts with both c-erbB-2-positive tumor cells and CD3+ CTL. Human CD4+ helper/killer T cells, induced from peripheral-blood mononuclear cells by activation with immobilized anti-CD3 monoclonal antibody (MAb) plus IL-2, showed no significant cytotoxicity against tumor cells. However, treatment of human CD4+ helper/killer cells with the BsAb caused the induction of specific cytotoxicity against c-erbB-2-positive tumor cells. CD4+ helper/killer cells also produced significant amounts of IL-2 during co-culture with c-erbB-2-positive tumor cells in the presence of the BsAb. Moreover, by combination with the BsAb, CD4+ helper/killer cells showed a strong in vivo anti-tumor effect against c-erbB-2 transfectant or human colon-cancer cells implanted in nude mice. Our results strongly suggest that the c-erbB-2 proto-oncogene product on human tumor cells may be a good target for BsAb-directed adoptive tumor immunotherapy.

The expressions of epidermal growth factors (EGF), epidermal growth factor receptors (EGFR), and the c-erbB-2 oncoprotein were immunohistochemically examined in 25 cases of human pancreatic carcinoma and epineoplastic pancreatitis and in 10 non-cancerous/non-inflammatory pancreatic tissues. The positive rates of EGF, EGFR, and the c-erbB-2 oncoprotein in cancer tissues were 72%, 36%, and 28%, respectively. EGF was stained mainly in the cytoplasm and partly on the surfaces of the cancer cells. EGFR and the c-erbB-2 oncoprotein were stained mainly on the surfaces of the cancer cells and partly in the cytoplasm. The expressions of these 3 products correlated significantly with tumor invasion into the anterior and posterior areas surrounding the pancreas. In the EGF, EGFR, and c-erbB-2 positive cancer tissues, some stromal cells, that is fibroblasts and endothelial cells, were also positive. In the adjacent pancreatic tissues with inflammation, these products were noted in some ductal cells, acinar cells, fibroblasts and endothelial cells. No distinct staining was detected in non-cancerous/non-inflammatory tissues. The survival period for patients who tested positive for these three proteins was statistically shorter than for those who tested negative. These results suggest that the coexpression of EGF and EGFR and the expression of the c-erbB-2 oncoprotein are related to the existence of the invasion of human pancreatic cancer. Furthermore, an immunohistochemical examination of these three products is useful in forming a prognosis for pancreatic cancer patients.

The HER-2/neu oncogene encodes a Mr 185,000 transmembrane phosphoglycoprotein which is overexpressed in 25-35% of breast and ovarian neoplasms and portends a poor prognosis. We have studied the feasibility of targeting this oncoprotein, designated p185, with radioiodinated murine monoclonal antibodies (muMABs) 4D5 and 7C2, which recognize distinct epitopes on its extracellular domain. The rates of internalization and catabolism of these antibodies were analyzed by cellular radioimmunoassay and electron microscopy. After binding to NIH3T3 HER-2/neu cells, which show high surface expression of p185, the muMABs were endocytosed via coated pits, routed to lysosomes, and degraded. Approximately 44% of 125I-4D5 and 39% of 125I-7C2 were catabolized by tumor cells after 24 h. The biodistribution of radiolabeled 4D5 and 7C2 were evaluated in beige/nude mice bearing s.c. NIH3T3 HER-2/neu grafts. A high specificity of localization was seen with tumor:organ ratios of activity generally ranging from 5:1 to 30:1. However, the percentage injected dose of radioactivity per gram of tumor declined sharply from 25% at 24 h to 5% at 120 h postinjection. Treating the animals with 400-700 muCi 131I-4D5 caused a marked inhibition of tumor growth, although no mice were cured. Unlabeled 4D5 had no effect on tumor progression in this model, but administering 400-700 muCi of 131I-DA4-4, an isotype-matched irrelevant muMAB, resulted in an intermediate degree of growth retardation. Analysis of kinetic blood data and whole-body time-activity curves indicated that the irrelevant conjugate remained in the body 2-3 times longer than 131I-4D5. Radioiodinated anti-HER-2/neu muMABs are attractive agents for radioimmunodiagnosis and radioimmunotherapy of aggressive HER-2/neu-positive breast and ovarian carcinomas, but effective strategies for retarding intratumoral catabolism may be necessary to optimize their clinical utility.

Sections of formalin-fixed, paraffin-blocked tissue from 116 primary transitional cell carcinomas were stained immunohistochemically using a polyclonal antibody against the c-erbB-2 oncoprotein. Positive staining of cell membranes, known to correlate with gene amplification, was seen in 22 (19%) of the 116, with variable staining from tumour to tumour and within tumours themselves. Consistent with its mooted value as a prognosticator in bladder cancer, the c-erbB-2 oncoprotein was detected in 13 (of 40) grade III and 9 of the 26 muscle-invasive tumours examined compared to 1 (of 25) grade I and 6 (of 66) mucosa only (pTa) lesions. These results support further examination of c-erbB-2 expression in bladder cancer.

The mechanism by which HER2/neu overexpressing tumor cells resist NK, LAK, and LDCC cytotoxic lymphocytes was investigated. Resistance was not explained by a delay in kinetics of lysis, concurrent resistance to TNF, or a diminished expression of the transferrin receptor. HLA-class I expression, however, was markedly elevated compared to HER2 nonexpressing targets suggesting a reason for resistance. To test the role of class I, we selectively decreased expression by incubation of targets with beta-2 microglobulin anti-sense oligonucleotides. Anti-sense-treated HER2+ targets, displaying levels of class I comparable to HER2- targets, were still markedly resistant to cytotoxic effectors. Down-regulation of class I expression in HER2- carcinoma cells also had no effect on sensitivity to cytotoxicity by anti-sense treatment of Raji and U937 targets resulted in enhanced sensitivity to NK and LAK effectors but not to T cells mediating LDCC. These data indicate resistance to cytotoxicity in HER2-expressing targets cannot be solely explained by heightened expression of class I. The data also support the concept that class I expression regulates sensitivity to NK and LAK cells (but not LDCC effectors) in selected targets.

In this investigation, 83 human mammary carcinomas were examined for the expression of oestrogen receptor (ER), epidermal growth factor receptor (EGF-R), epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha), c-erbB-2, histological grade, mitotic index and nodal status, ALL of which are reportedly prognostically significant factors (Bloom and Richardson 1957; Baak et al. 1985; Wright et al. 1989). ER expression was biochemically recognized in 43.4% of mammary carcinomas, and EGF-R, EGF, TGF-alpha and c-erbB-2 were histochemically recognized in 25.3, 14.5, 27.7 and 18.0% of mammary carcinomas examined respectively, using conventional sections of buffered formalin-fixed, paraffin-embedded tissue and monoclonal or polyclonal antibodies. There were significant relationships between negative ER and positive EGF-R or TGF-alpha; positive EGF-R and TGF-alpha; positive EGF-R and c-erbB-2; and positive c-erbB-2 and TGF-alpha. The single changes which were the negative ER and the positive c-erbB-2 correlated with histological grade and mitotic index. Co-expression of EGF-R and TGF-alpha correlated with positive nodal status. Therefore, the present investigation indicates that the negative ER, single expression of c-erbB-2 and co-expression of EGF-R and TGF-alpha are important markers which contribute indirectly to prognosis, which reconfirms previous findings on the former two while adding the new finding that immunohistochemical demonstration of expression of EGF-R and TGF-alpha may provide useful information for selecting the appropriate treatment.

PURPOSE: A study was undertaken to define the prognostic value of the expression of the c-erbB-2 oncoprotein in a series of breast cancer patients when compared by multivariate analysis with expression of the epidermal growth factor receptor (EGFR), DNA ploidy, and conventional clinicopathologic features. PATIENTS AND METHODS: Prognostic indicators were analyzed in 165 primary breast cancers. The c-erbB-2 oncoprotein was recognized by the polyclonal antibody 21N using an immunocytochemical method. expression of the EGFR was stated immunocytochemically using the monoclonal antibody EGFR1. DNA ploidy was assessed in paraffin-embedded sections using a standard flow-cytometric method. RESULTS: Overall, 27% of carcinomas had membrane 21N-staining and were classified as c-erbB-2-positive. Overexpression of the c-erbB-2 oncoprotein was poorly associated with EGFR expression and the conventional pathologic features, and it was weakly associated with DNA ploidy and nodal status. Univariate analysis showed that c-erbB-2 expression, nodal status, DNA ploidy, and EGFR provided significant prognostic information concerning 4-year relapse-free survival (RFS) with the odds ratios (ORs) of not relapsing of 2.94, 2.83, 2.34, and 2.20, respectively. Regarding overall survival (OS) at 4 years, only nodal status and DNA ploidy had prognostic significance, with the ORs of not dying of 2.68 and 2.80, respectively. Applying multivariate analysis to RFS, 21N when adjusted for nodal status, EGFR, and DNA ploidy (full model) failed to retain prognostic value (P = .202), whereas nodal status was the most significant indicator of relapse (P = .027) followed by DNA ploidy (P = .056) and EGFR (P = .093). CONCLUSIONS: This study suggests that overexpression of the c-erbB-2 oncoprotein appears to be an important indicator of relapse in stage I-II breast cancer when singly evaluated. Multivariate analysis shows that the determination both of nodal status and DNA ploidy improves our ability to identify subsets of patients with different prognoses, and allows for a better selection of patients for systemic adjuvant treatments.

Amplification and overexpression of the HER2 (c-erbB-2) oncogene was assessed in paraffin-embedded specimens from 27 in situ carcinomas of the breast and from 122 stage II breast cancers. Gene amplification detected in these archival tissues by differential polymerase chain reaction (PCR) was found in 48% of in situ carcinomas and in 21% of stage II lesions (chi 2 = 7.62, p less than or equal to 0.01). In addition, the level of gene amplification correlated with the level of HER2 oncoprotein expression as measured by immunohistochemistry for both in situ cancers (p less than or equal to 0.025) and stage II cancers (p less than or equal to 0.0005). This high incidence of HER2 gene amplification with accompanying overexpression in non-invasive breast tumors suggests that perturbations of the HER2 oncogene are among the earliest and most common genetic lesions in human breast cancer.

203 tumor specimens from 175 patients were studied. Amplification of ERBB-2 was detected in 14 out of 63 (22%) cases of breast carcinoma, in 1 out of 23 patients with ovarian cancers, in 1 out of 19 cases of colon carcinoma and in 1 out of 27 patients with thyroid cancer. We failed to find more than one copy of ERBB-2 in 34 patients with lung cancers, 6 with sarcomas and 3 with melanomas. There was tendency toward correlation between ERBB-2 amplification and lymph node involvement in patients with breast carcinoma. Thus, the oncogene ERBB-2 is often amplified in human tumors, but breast cancer is characterized by an especially high frequency of ERBB-2 amplification.

The expression of oncogene products related to cell growth (c-erbB-2, c-myc, ras p21, EGFR) was investigated in benign (15 cases) and malignant breast lesions (20 cases) by means of immunohistochemistry using the avidin-biotin-peroxidase technique with polyclonal and monoclonal antibodies. The aim of this study was to evaluate the relationship between the staining positivity and various morphological and biological features, such as tumour type, grading, hormone receptor status and cell kinetic parameters. In benign breast lesions, as expected, the kinetic parameters were low, both for Ki-67 and LI. ALL the specimens showed a diploid condition (the DI being equal to 1) and we found a limited degree of immunoreactivity for ALL the growth factors and oncogene products. In breast cancer we studied the distribution of immunohistochemical positivity for EGFR, c-erbB-2, c-myc, ras p21 and Ki-67, which was related to age, nodal status, ER and PgR receptor status, LI, DI and histopathological grading. A significant positive correlation was found both between ras p21 expression and nodal status and ER-ICA positivity. We observed a strong correlation between LI and Ki-67 and an inverse relation between Ki-67 and ER expression. These findings suggest the importance of studying the relationship between prognostic factors which may provide preoperative prediction in the biological behaviour of breast cancer, not only on biopsy specimens, but also on fine needle aspirates.

The HER-2/neu oncogene (a member of the Erb-like oncogene family) is distinct from but closely related to the c-erb B gene which encodes the epidermal growth factor receptor (EGFr). HER-2/neu gene amplification was found in a large number of mammary carcinomas and there was a strong correlation between this phenomenon and poor prognosis. In our study HER-2/neu oncogene expression was determined in 16 malignant ovarian tumors, 2 ovarian lymphomas and 5 normal ovaries. The HER-2/neu gene was found both in normal ovaries and malignant tumors, without any apparent difference among the various histological types. In ALL the specimens examined, HER-2/neu expression did not seem to be related to EGF binding capacity.

The amplification grade of oncogene c-erbB-2 was examined by the polymerase-chain-reaction-method in DNA s of 56 primary mammary carcinomas. 26 (46.4%) of these showed the amplified oncogene c-erbB-2. In the strongly amplified cases, the expression of the c-erbB-2 oncoprotein was verifiable immunohistochemically. Between the progesterone receptor status (PR) and the amplified c-erbB-2 oncogene there was a statistically proven dependency. No correlation was observed between the amplified c-erbB-2 oncogene and the epidermal growth-factor receptor (EGFR).

Amplification of the proto-oncogene HER-2/neu and/or overexpression of the transmembrane protein p185erbB2 that it encodes occur in approximately 30% of human breast and gynaecological cancers seen clinically and are strongly associated with an unfavourable outcome. We report on the use of a new monoclonal antibody (Mab-145ww) together with immunoblotting for detection of p185erbB2 in membranes that remain after routine processing of breast cancer tissue for steroid receptor assays. Human breast cancer cell lines SKBR3 and MCF-7 were used as high and low controls, respectively, for p185erbB2 expression. Mab-145ww was detected p185erbB2 in more than half of the breast cancer specimens; the expression was intense in SKBR3 cells, but only faint in MCF-7 cells. These results demonstrate that routine processing of cancer tissue for steroid receptor status can include providing a preparation with which to assess p185erbB2 expression and, thus, can provide information potentially useful for the clinical management of individual cancer patients.

Overexpression of c-erbB-2 occurs in 60% of in situ and 25% of infiltrating ductal carcinomas. We have previously found very strong associations between immunohistochemical staining for c-erbB-2 and histological pattern and nuclear size in ductal carcinoma in situ (DCIS) and less strong correlation with proliferative activity. In a further study of infiltrating ductal carcinomas we have found that, in addition to tumours arising from c-erbB-2 positive, large celled, rapidly proliferating, comedo carcinomas and c-erbB-2 negative small celled cribriform/micropapillary carcinomas with a low proliferative rate, there is a third group of c-erbB-2 negative tumours with large nuclei and variable proliferative activity. These latter tumours are not seen in pure DCIS suggesting that they have a very transient in situ stage. Therefore, although in pure DCIS c-erbB-2 positively appears to be associated with tumours with a greater invasive potential, and c-erbB-2 negativity with tumours having a more favourable prognosis, the latter is not necessarily true in infiltrating disease.

The relationship was assessed between c-erbB-2 oncoprotein expression and other prognostic factors in breast cancer, such as axillary and internal mammary node metastases. The value of these indicators was analyzed in estimating prognosis, especially in patients with axillary node-positive breast cancer. These results showed that c-erbB-2 is significantly related to clinical stage and axillary node metastases. A univariate study revealed that disease-free and overall survival were correlated significantly with clinical stage, tumor size, axillary and internal mammary node metastases, and 21N status. Among the patients with axillary node involvement, however, 21N status did not appear to be a significant additional prognostic factor. Internal mammary node metastases were significant. In a multivariate study, only axillary and internal mammary node metastases were significant prognostic factors for either the entire group of patients or those with positive axillary nodes. Therefore, axillary node dissection and biopsy of the internal mammary nodes may provide important prognostic information for patients with breast cancer.

The expression of the c-erbB-2 proto-oncogene product was investigated immunohistochemically in 474 formalin-fixed and paraffin-embedded human breast tissue samples. The series included 32 benign and 26 hyperplastic lesions, 32 carcinomas in situ and 384 invasive breast carcinomas, 107 of which were less than 1 cm in diameter. Cytometric DNA assessments were performed on histopathologically or cytodiagnostically identified cell nuclei, using image analysis. C-erbB-2 immunoreactivity was not seen in normal parenchyma or in benign and hyperplastic lesions. Mammary carcinomas in situ were more frequently immunoreactive (59%) than invasive neoplasms (23%). Invasive tumours more than 1 cm in diameter immunoreacted more often (26%) than small invasive carcinomas (16%). C-erbB-2 expression in regional lymph node metastases was the same as in the corresponding primary tumours. Significant differences were observed between the c-erbB-2 expression in DNA diploid and aneuploid lesions; for carcinomas in situ the figures were 40% and 72%, respectively. Invasive carcinomas of DNA diploid type rarely showed c-erb-B-2 expression, irrespective of tumour size and nodal status (7-11%). DNA aneuploid tumours were more frequently immunoreactive with increasing levels during progression (32-41%). Our data indicate that genetically stable invasive mammary tumours seem rarely to express the c-erbB-2 protein, even during progression, whereas genetically unstable invasive neoplasms frequently show c-erbB-2 immunoreactivity which increases during tumour progression.

The prognostic value of c-erbB-2 protein expression was assessed retrospectively in 87 "curative" gastrectomy specimens from patients with gastric carcinoma. tumours were stained immunohistochemically with the specific antibody 21N. Eight (9%) cases had strong membrane staining, ALL of which were of the intestinal type, and lymph node metastases, which showed concordance of staining in seven cases. In contrast to studies in breast cancer, positive cases showed a trend towards better five year survival, but this did not reach significance.

The neu protooncogene encodes a tyrosine kinase receptor that is involved in the regulation of normal growth and malignant transformation. To circumvent the use of the incompletely characterized ligand of Neu, we constructed a chimeric protein composed of the ligand-binding domain of the epidermal growth factor receptor and the transmembrane and cytoplasmic portions of Neu. By expressing this Neu-epidermal growth factor receptor chimera (termed NEC), we found that following stimulation by the heterologous ligand, the tyrosine kinase of Neu became associated with a phosphatidylinositol (PI) kinase activity. The association was dependent on the concentration of the ligand and was almost maximal within 30 s after ligand binding. The lipid kinase was identified as a type I PI 3 -kinase on the basis of its inhibition by Nonidet P-40 and high pressure liquid chromatography of the phosphorylated product. To confirm the identification of PI 3 -kinase as an effector of Neu, we raised antibodies to the alpha-isoform of the regulatory subunit of PI 3 -kinase (p85). Using these antibodies, it was possible to directly demonstrate ligand-dependent formation of a tyrosine-phosphorylated complex of NEC and PI 3 -kinase. Apparently, both PI 3 -kinase and phospholipase C gamma, another substrate of the Neu kinase, simultaneously associated with the same activated NEC molecule. Nevertheless, immunofluorescence localization of PI 3 -kinase revealed no significant cellular redistribution of the enzyme after activation of the Neu kinase. Interestingly, PI 3 -kinase was localized primarily to the cell nucleus and to confined regions of the plasma membrane. Analysis of mutants of the Neu protein indicated that the oncogenic point-mutated Neu (Glu664) was permanently coupled to PI 3 -kinase; but two nontransforming versions of the oncoprotein, a kinase-defective protein and a carboxyl-terminally deleted Neu, were devoid of the constitutive association with PI 3 -kinase. Hence, we concluded that phosphatidylinositol 3 -kinase is a physiological substrate of the Neu receptor, but the regulation of this coupling is released upon oncogenic activation.

The neu protooncogene encodes a tyrosine kinase receptor that is involved in the regulation of normal growth and malignant transformation. To circumvent the use of the incompletely characterized ligand of Neu, we constructed a chimeric protein composed of the ligand-binding domain of the epidermal growth factor receptor and the transmembrane and cytoplasmic portions of Neu. By expressing this Neu-epidermal growth factor receptor chimera (termed NEC), we found that following stimulation by the heterologous ligand, the tyrosine kinase of Neu became associated with a phosphatidylinositol (PI) kinase activity. The association was dependent on the concentration of the ligand and was almost maximal within 30 s after ligand binding. The lipid kinase was identified as a type I PI 3 -kinase on the basis of its inhibition by Nonidet P-40 and high pressure liquid chromatography of the phosphorylated product. To confirm the identification of PI 3 -kinase as an effector of Neu, we raised antibodies to the alpha-isoform of the regulatory subunit of PI 3 -kinase (p85). Using these antibodies, it was possible to directly demonstrate ligand-dependent formation of a tyrosine-phosphorylated complex of NEC and PI 3 -kinase. Apparently, both PI 3 -kinase and phospholipase C gamma, another substrate of the Neu kinase, simultaneously associated with the same activated NEC molecule. Nevertheless, immunofluorescence localization of PI 3 -kinase revealed no significant cellular redistribution of the enzyme after activation of the Neu kinase. Interestingly, PI 3 -kinase was localized primarily to the cell nucleus and to confined regions of the plasma membrane. Analysis of mutants of the Neu protein indicated that the oncogenic point-mutated Neu (Glu664) was permanently coupled to PI 3 -kinase; but two nontransforming versions of the oncoprotein, a kinase-defective protein and a carboxyl-terminally deleted Neu, were devoid of the constitutive association with PI 3 -kinase. Hence, we concluded that phosphatidylinositol 3 -kinase is a physiological substrate of the Neu receptor, but the regulation of this coupling is released upon oncogenic activation.

PURPOSE: To study retrospectively the long-term prognostic significance of HER-2 oncoprotein expression in breast cancer (BC). PATIENTS AND METHODS: Two hundred nine consecutive female patients with invasive operable BC from a defined urban population were observed for a median of 30 years. Tissue expression of HER-2 oncoprotein was demonstrated by using an immunoperoxidase procedure. RESULTS: Fifty-five (26%) patients had cancer and a positive HER-2 oncoprotein stain reaction. They had significantly worse 10- and 25-year survival rates than those patients who had a negative stain reaction in their cancer (31% v 48% and 31% v 39%, respectively; P = .004). HER-2 expression was also associated with a poorer survival among patients who had axillary nodal metastases (P = .003; n = 104), but not among those patients who did not have metastases. HER-2 expression was related to the ductal histologic type, poor histologic grade, and high mitotic count, but not to tumor size, axillary nodal status, DNA ploidy, or S-phase fraction (SPF). In a multivariate analysis among patients with nodal metastases, HER-2 expression was an independent prognostic factor (P = .04) that predicted poor survival. However, if the entire series was entered onto the analysis, it did not emerge as an independent factor. CONCLUSIONS: HER-2 oncoprotein expression has long-term prognostic significance for predicting poor survival in BC, and it has an independent prognostic value among patients who presented with axillary nodal metastases. This result is contradictory to the argument that HER-2 expression is only a marker for drug resistance because the patients were not given adjuvant drug therapy.

The expression of the Her2/neu gene product p185 was retrospectively analyzed in 58 patients with gastric carcinoma. The results were correlated to various clinicopathological and prognostic factors. Positive membrane staining for p185 could be detected in 38% of the patients (22/58). Membrane staining was significantly greater in well and moderately differentiated tumors of the intestinal type when compared with poorly differentiated lesions and carcinomas of the diffuse type (P less than 0.01). Positive membrane staining did not correlate with site and tumor stage, but T1 lesions had less membrane staining than more advanced primary tumors. Overall survival showed no difference between p185-positive and negative cases. Multivariate analysis defined a subgroup of curatively resected patients with stage III and IV disease that had a statistically significant poorer survival when p185 was overexpressed (P = 0.005). Overexpression of the Her2/neu product p185 appears to be associated with intestinal-type gastric carcinoma and may help in identifying a subset of patients at increased risk for shorter survival.

As the factor binding to the neu protein has been unknown, it has not been possible to confirm experimentally the proposed growth-factor receptor like functions of the neu protein. To approach this problem we constructed a recombinant receptor which enabled ligand regulation of the neu tyrosine kinase. The hybrid receptor consisted of the extracellular ligand binding, transmembrane and protein kinase C-substrate domains joined to the intracellular tyrosine kinase and carboxyl-terminal domains of the neu protein. Several properties of NIH3T3 cells carrying this construct were tested. We obtained the first experimental evidence that the neu proto-oncogene has mitogenic and transforming activities only in the presence of a ligand stimulating its tyrosine kinase activity. Various cellular and molecular biological parameters indicated that the chimeric receptor behaved very similarly to the EGFR. Also, this chimeric receptor has allowed us to compare the constitutive oncogenic and the ligand-activated non-oncogenic activities of the neu tyrosine kinase. In the future we plan to focus on characterization of possible differences between EGFR and neu signalling in more differentiated cellular backgrounds.

The rat neu oncogene product is a member of the epidermal growth factor (EGF) receptor subgroup of the superfamily of growth factor receptor tyrosine kinases. The oncogenic activation of the neu protein occurs by a point mutation within its transmembrane region which results in an increase in its tyrosine kinase activity. Using three different forms of neu expressed in insect cells via baculovirus infection, we have examined the biochemical differences between the normal and transforming forms of neu and investigated the role of the transmembrane domain in its tyrosine kinase activity. One form of neu which was expressed in insect cells consisted of the complete tyrosine kinase domain but lacked the extracellular and transmembrane regions (designated NTK). The other two forms consisted of the tyrosine kinase domain, the transmembrane domain, and 40 amino acids of the extracellular domain. One of these transmembrane forms of neu contained the normal valine residue at position 664 within the transmembrane region (MS-N), while the other contained the oncogenic glutamic acid residue at this position (MS-T). Direct comparisons of NTK, MS-N, and MS-T have shown that the NTK protein is capable of the highest extents of both autophosphorylation activity and the tyrosine phosphorylation of exogenous substrate, suggesting that the presence of the transmembrane region of neu suppresses the tyrosine kinase activity of this receptor. In addition, we have found that the oncogenic point mutation within the transmembrane region stimulates the tyrosine kinase activity of the neu protein by allowing it to more effectively utilize Mg2+. Overall, the results of these studies suggest that the valine to glutamic acid substitution at position 664 may at least partially relieve a negative constraint imparted by the membrane-spanning domain on the tyrosine kinase activity of neu and enables a more effective use of Mg2+ in the catalysis of tyrosine phosphorylation of exogenous substrates.

Capillary electrophoresis (CE) with a sieving buffer containing ethidium bromide was applied to the detection of PCR-amplified RFLP samples. With CE, in contrast to agarose gel electrophoresis, run times are short, i.e., typically less than 30 min, the capillary can be re-used, and full automation is feasible. The addition of ethidium bromide to the buffer system in conjunction with a field amplification injection technique led to increased sample detectability and resolution. Migration time precision was better than 0.2% RSD with a approximately 12-bp resolution for the DNA fragment sizes of interest. RFLP samples were analyzed for homo- or heterozygosity based on the presence of 500- and/or 520-bp DNA fragments. Special software was used to correct for run-to-run migration time variations, thus facilitating genotype assignment.

To study the tissue-specific expression of neu oncogene, we used two mouse tumor cell lines derived from liver, Hep1-a, and pancreatic, 266-6, tumors as a model system. The endogenous neu gene is expressed in Hep1-a but not in 266-6 cells. We demonstrate in this report that differential expression of the neu gene in these two cell lines is mainly regulated at transcriptional level. The neu promoter sequence responsible for the differential regulation is localized within a 90 bp region and it is possibly due to lack of a specific positive transcription factor(s) interacting with this region in 266-6 cells.

To study the tissue-specific expression of neu oncogene, we used two mouse tumor cell lines derived from liver, Hep1-a, and pancreatic, 266-6, tumors as a model system. The endogenous neu gene is expressed in Hep1-a but not in 266-6 cells. We demonstrate in this report that differential expression of the neu gene in these two cell lines is mainly regulated at transcriptional level. The neu promoter sequence responsible for the differential regulation is localized within a 90 bp region and it is possibly due to lack of a specific positive transcription factor(s) interacting with this region in 266-6 cells.

Amplification or increased expression of the c-erbB-2 gene has previously been reported to be a prognostic marker for breast cancer. Gene amplification is usually measured by Southern blotting, whereas increased protein expression is usually detected by immunocytochemistry. We measured c-erbB-2 protein with an enzyme-linked immunosorbent assay (ELISA). High concentrations of oncoprotein were found in 25 of 161 (16%) primary breast cancers and in 3 of 6 (50%) breast cancer metastases. High concentrations were not found in normal breast tissue or benign breast tumors. In the primary cancers, high concentrations of c-erbB-2 protein were found more frequently (a) in estrogen receptor-negative tumors than in estrogen receptor-positive tumors, (b) in progesterone receptor-negative tumors than in progesterone-positive tumors, and (c) in axillary node-positive cancers than in node-negative cancers. Patients with tumors containing high amounts of the c-erbB-2 protein had a significantly shorter (P less than 0.001) disease-free interval and overall survival rate than did patients with low amounts. We conclude that assay of c-erbB-2 protein by ELISA is simple, rapid, and quantitative and offers important prognostic information in breast cancer.

In order to analyze the correlation between immunohistochemical positivity for c-erbB-2 oncoprotein and prognosis in patients with malignant salivary gland tumors, 59 cases of malignant tumors of the major salivary glands, including 35 parotid gland, 20 submaxillary gland and 4 sublingual gland tumors, were studied immunohistochemically using a polyclonal antibody against c-erbB-2 oncoprotein. Positive staining was observed in 13 (22%) of the 59 cases. Interestingly, positive results were obtained only in adenocarcinoma (6/20) and carcinoma in pleomorphic adenoma (7/15), and not in any other histological types such as adenoid cystic carcinoma, mucoepidermoid tumor, and squamous cell carcinoma. There was no correlation between the degree of differentiation of adenocarcinoma and c-erbB-2 positivity. Since the carcinoma in pleomorphic adenoma positive for c-erbB-2 oncoprotein was adenocarcinoma, adenocarcinoma and adenocarcinoma in pleomorphic adenoma were placed together (n = 33), and the presence or absence of c-erbB-2 oncoprotein in this group was examined for correlation with patients survival and other clinicopathological features, including clinical stage, tumor size, surgical margins, and lymph node status. The c-erbB-2-positive tumors tended to be more advanced and larger than negative tumors. Similarly, c-erbB-2-positive tumors were difficult to resect completely, were associated with lymph node metastasis more frequently, and showed lower disease-free survival than negative cases (P less than .05). We conclude that immunohistochemical positivity for c-erbB-2 is an indicator of aggressiveness in both adenocarcinoma and adenocarcinoma in pleomorphic adenoma of the major salivary glands.

Both amplification and overexpression of c-erb B-2/neu have been associated with the progression and possible prognosis of a number of human cancers. In this study, we demonstrated that c-erb B-2/neu may also play an important role in human prostate cancer. Our conclusion is based on the following observations: (1) A monoclonal antibody raised against a peptide sequence from the C-terminal domain of the human c-erb B-2/neu gene product reacted positively with 68.7% (11 of 16) of the human prostatic cancer tissue extracts analyzed by western blot procedure. These results were supported by the immunohistochemical staining of the prostatic cancer specimens; 80% (12 of 15) showed positive staining, primarily around the plasma membranes of the prostatic cancer cells. c-erb B-2/neu oncoprotein was not detectable in normal prostate tissues (five examined by immunohistochemical staining and three by western blotting) or in human benign prostatic hyperplasia (two examined by immunohistochemical staining and six by western blotting) and was expressed less abundantly with lower intensity in "normal" human prostate tissues adjacent to cancerous prostate tissue (5 of 12 examined by immunohistochemical staining). We observed no evidence of c-erb B-2/neu gene amplification in 10 fresh human prostatic cancer specimens examined by Southern blotting and in the cultured human prostatic cancer cell lines PC-3, DU-145, and LNCaP. (2) The c-erb B-2/neu protein was detected in both androgen-receptor-positive (LNCaP) and -negative (PC-3 and DU-145) human prostate cancer cell lines. Positive immunostaining of c-erb B-2/neu protein was found to be associated predominantly with the plasma membranes of PC-3 cells, but was also found to be widespread in the cytoplasmic region of the LNCaP cells and in the perinuclear region of the DU-145 cells. (3) Like prostate-specific antigen (PSA) expression, c-erb B-2/neu mRNA expression was also positively regulated by androgen in androgen-receptor-positive LNCaP cells in vitro and LNCaP tumors in vivo. When LNCaP tumors were grown in castrated male hosts, levels of c-erb B-2/neu and PSA mRNA expression decreased initially, but rebounded at 3 wk to levels comparable to those expressed by tumors maintained in intact adult male hosts.

The rat neu oncogene encodes a constitutively activated growth factor receptor/transmembrane tyrosine kinase, p185Tneu, that is structurally similar to yet distinct from the epidermal growth factor receptor. To explore the role of the carboxyl-terminal region and of putative autophosphorylation sites in regulating the activity of the rat p185Tneu (T, transforming) protein, we used site-directed mutagenesis to generate a p185Tneu mutant in which a putative tyrosine autophosphorylation site (residue 1253) at the extreme carboxyl terminus was replaced by a phenylalanine residue and a mutant in which the carboxyl-terminal 122 amino acids were deleted. These proteins were expressed in NIH 3T3 cells at comparable levels and exhibited similar autophosphorylation activity, exogenous substrate phosphorylation ability, oligomerization levels, and responsiveness to a partially purified neu-activating factor. However, the mutant p185Tneu proteins displayed a decreased transforming capacity both in vitro and in vivo. This analysis demonstrated that the carboxyl-terminal domain and at least one putative tyrosine autophosphorylation site of p185Tneu play a role in positively regulating the cell growth-regulating properties of the neu protein.

The overexpression of the proto-oncogene HER-2 (c-erbB-2/neu) in ovarian and mammary carcinoma is an important indicator for a bad prognosis. In this study we demonstrate that in 7 out of 8 ovarian carcinoma cell lines there is an interferon-gamma-mediated reduction in HER-2 specific protein, and this effect was found to correlate with the antiproliferative action. It is interesting to note that there is no relationship between the absolute amount of HER-2 protein expressed and the sensitivity of the ovarian carcinoma cells for an antiproliferative activity of interferon-gamma. Other chemotherapeutic agents did not affect HER-2 expression although they inhibited the proliferation. The oncogene expression was lowered only in the ovarian carcinoma cell lines and not in 3 interferon-gamma sensitive human breast cancer cell lines. expression of the oncogene HER-2 is the leading prognostic factor in ovarian cancer. Its modulation might represent a mechanism by which interferon-gamma inhibits cell proliferation.

Monoclonal antibody PAb3 to c-erbB-2/neu protein was utilized in the immunoperoxidase staining of 86 human specimens from oral mucosa. These tissue specimens represented a spectrum from 7 normal to 9 simple hyperplasia, 15 mild dysplasia, 14 moderate dysplasia, 20 severe dysplasia and 21 squamous cell carcinoma. Our study indicated that as the cells acquire a more malignant phenotype, there was a progressive increase in neu expression. It also suggested that neu may be involved in the development of oral cancers and that its evaluation in the early stages may assist in the diagnosis and management of oral cancers.

Monoclonal antibody PAb3 to c-erbB-2/neu protein was utilized in the immunoperoxidase staining of 86 human specimens from oral mucosa. These tissue specimens represented a spectrum from 7 normal to 9 simple hyperplasia, 15 mild dysplasia, 14 moderate dysplasia, 20 severe dysplasia and 21 squamous cell carcinoma. Our study indicated that as the cells acquire a more malignant phenotype, there was a progressive increase in neu expression. It also suggested that neu may be involved in the development of oral cancers and that its evaluation in the early stages may assist in the diagnosis and management of oral cancers.

In order to identify potential markers of malignancy in diagnostic respiratory cytopathology, c-myc and c-erbB-2 proto-oncogene expression was studied in fine needle aspirates from 14 consecutive fresh operation tissue samples (after surgical removal) representing lung tumors and a variety of other cell samples by in situ hybridization of 35S-labeled antisense and sense RNA c-myc and c-erbB-2 specific proto-oncogene probes. ALL 14 lung tumors showed c-myc expression and eight also showed c-erbB-2 expression. On average, the c-myc expression was about 4 times higher than that of c-erbB-2 (P less than 0.001). c-erbB-2 expression, confirmed also as a cytoplasmic membrane-bound reactivity by immunohistochemical stainings for c-erbB-2 oncoprotein, was significantly related to adenocarcinoma (P less than 0.025), whereas increasing tumor size correlated significantly with increasing c-myc expression (P less than 0.05). On average, ALL the tumor cell lines showed 2-fold expression of c-myc compared with the lung tumors (P less than 0.025). c-erbB-2 expression was found in six of 11 cell lines. High c-myc proto-oncogene expression was also found in broncho-epithelial cells and alveolar macrophages, and a low expression was found in lymphocytes but not in neutrophils, while none of these cells showed c-erbB-2 proto-oncogene expression. Our results demonstrate extensive c-myc proto-oncogene expression in both malignant and non-neoplastic proliferating cells, but not in terminally differentiated cells such as neutrophils. Therefore c-myc expression must also be related to general cell proliferation and not only malignancy per se. In marked contrast, c-erbB-2 proto-oncogene expression was found only in adenocarcinoma cells, and thus can be used as a marker for malignancy in diagnostic respiratory cytopathology.

expression of the c-erbB-2 (neu, HER-2) oncogene is found to be subjected to hormonal and developmental regulation in normal as well as neoplastic mammary cells. We have previously reported that estrogens inhibit c-erbB-2 expression at both the mRNA and protein level in estrogen receptor (ER)-positive, but not in ER-negative, breast cancer cell lines. Reversion of c-erbB-2 inhibition is seen with tamoxifen. The effect on c-erbB-2 expression of several other hormones and factors, which influence mammary cell growth and differentiation, has been studied. Our observations indicate that, in normal and neoplastic mammary cells, c-erbB-2 expression is inversely related to cell proliferation. While estrogens, anti-estrogens and cAMP clearly regulate c-erbB-2 mRNA levels, epidermal growth factor dramatically decreases the c-erbB-2 protein without affecting the level of c-erbB-2 mRNA. Therefore, different signals converging in terms of cell proliferation regulate c-erbB-2 expression by different molecular mechanisms.

Abnormalities of epidermal growth factor receptor (EGFR) and c-erbB-2 have been demonstrated to be correlated with aggressive biologic behavior in a variety of human cancers. To analyze the possible roles of these oncogenes in ovarian neoplasms, immunolocalization of EGFR and c-erbB-2 oncogene product was performed in 45 cases of human ovarian mucinous and serous cystadenomas, carcinomas of low malignant potential (LMP), and invasive carcinomas by employing antibodies against these oncogene products. EGFR immunoreactivity was present in 15 of 35 LMP and invasive carcinomas and 1 of 10 cystadenomas. On the contrary, immunoreactivity of p185, which is an oncogene product of c-erbB-2, was detected only in five cases of carcinoma and in no benign cystadenoma. These results indicate that EGFR may be involved in the neoplastic process in epithelial ovarian adenocarcinoma, especially mucinous carcinoma, but involvement of c-erbB-2 is probably not as prevalent as considered previously. Four of the five cases immunohistochemically positive for p185 were also positive for EGFR, which suggests that expression of EGFR and p185 is to some extent correlated in human ovarian carcinoma.

Paraffin wax sections of 70 surgically resected colorectal adenocarcinomas were examined for the overexpression of HER2/c-erbB-2 oncoprotein using three different specific antibodies and the avidin-biotin immunoperoxidase technique. The patients included 38 men and 32 women aged between 47 and 80 years. The tumours were derived from various parts of the large intestinal tract, and represented ALL three stages of Dukes classification and the three histological grades of differentiation. Many tumour sections also included adjacent normal or transitional mucosa. Eight tubular adenomas found in the colectomy specimens in association with some carcinomas were also examined. No positive membrane staining was seen in any of the 70 carcinomas, four adenomas, two hyperplastic polyps, nor in the adjacent normal or transitional mucosa. It is suggested that the overexpression of c-erbB-2 gene product is unlikely to be as common and as pronounced in colorectal adenocarcinoma as it is in ductal carcinoma of the breast.

Paraffin wax sections of 70 surgically resected colorectal adenocarcinomas were examined for the overexpression of HER2/c-erbB-2 oncoprotein using three different specific antibodies and the avidin-biotin immunoperoxidase technique. The patients included 38 men and 32 women aged between 47 and 80 years. The tumours were derived from various parts of the large intestinal tract, and represented ALL three stages of Dukes classification and the three histological grades of differentiation. Many tumour sections also included adjacent normal or transitional mucosa. Eight tubular adenomas found in the colectomy specimens in association with some carcinomas were also examined. No positive membrane staining was seen in any of the 70 carcinomas, four adenomas, two hyperplastic polyps, nor in the adjacent normal or transitional mucosa. It is suggested that the overexpression of c-erbB-2 gene product is unlikely to be as common and as pronounced in colorectal adenocarcinoma as it is in ductal carcinoma of the breast.

Monoclonal anti-proliferating cell nuclear antigen (PCNA PC10), which is directed against a 36 kDa auxiliary protein for DNA polymerase delta specific for the S-phase of cell cycle, was used to measure tumour cell proliferation in 4 lactating breasts and 98 benign and malignant breast tumours. The percentage of PCNA-positive cells determined by point counting was significantly lower in the lactating breast [mean 3.6%, standard deviation (SD) 0.67, n = 5] than in fibroadenoma and mastopathy (mean 23.7, SD 5.0, n = 2). Primary breast carcinoma showed a PCNA index ranging from 2% to 36% (mean 12.3, SD 9.3, n = 50), whereas in recurrent carcinoma the index was mean 28.5, SD 4.0. A high index was correlated with c-erbB-2 and epidermal growth factor (EGF) receptor membrane reactivity, worsening histological grade, poor survival and disease-free survival. The expression of c-erbB-2 and EGF receptor was associated with poor survival and disease-free survival in primary breast cancer patients.

The expression of c-erbB-2 oncoprotein and epidermal growth factor receptor (EGFR) was examined by immunocytochemical and radioreceptor assays in 115 patients with primary breast cancer. In 48 of 115 patients (42%), the assays were found to be positive for the expression of c-erbB-2 oncoprotein, and, in 44 of 115 (35%) patients, the assays were positive for the expression of EGFR. There was no correlation between the expression of c-erbB-2 oncoprotein and EGFR. Clinical survey demonstrated that both c-erbB-2 oncoprotein expression and EGFR expression have independent prognostic values. Furthermore, when patients were divided into three groups on the basis of the expression of both c-erbB-2 oncoprotein and EGFR, those who were found to be positive for the expression of both c-erbB-2 oncoprotein and EGFR showed a worse prognosis than other groups. These results suggest that the combination of the expression of both c-erbB-2 oncoprotein and EGFR may be important in selecting patients who have a poor prognosis.

Amplification and overexpression of the c-erbB-2 oncogene have been associated with a poor prognosis in breast cancer. The present study evaluates c-erbB-2 protein over-production in sarcomas and in small round-cell tumors of childhood by applying an immunohistochemical technique to formalin-fixed, paraffin-embedded tissues. This technique had previously demonstrated high sensitivity for the detection of c-erbB-2 activation. One peripheral neuroepithelioma demonstrated equivocal immunoreactivity for c-erbB-2 protein. There was no evidence of c-erbB-2 protein overproduction in 11 angiosarcomas, 21 chondrosarcomas, 10 epithelioid sarcomas, 14 Ewing s sarcomas, 20 hepatoblastomas, nine leiomyosarcomas, 12 liposarcomas, 13 malignant fibrous histiocytomas, nine malignant lymphomas, 15 neuroblastomas/ganglioneuroblastomas, 16 neurofibrosarcomas, 10 osteosarcomas, seven peripheral neuroepitheliomas, 10 rhabdomyosarcomas, six synovial sarcomas, and 20 Wilm s tumors. We conclude that overproduction of the c-erbB-2 protein is rare or absent in these neoplasms and that its detection is therefore not likely to be of practical utility in their pathologic evaluation and prognostication.

The human erbB-2 oncogene encodes a tyrosine kinase receptor. A ligand for the erbB-2 receptor (gp30), with an apparent molecular weight of 30,000, was reported to modulate the growth of cells overexpressing erbB-2. Whereas low concentrations of gp30 induced proliferation of these cells, higher concentrations inhibited their growth. To elucidate the cellular mechanisms underlying cell growth inhibition by gp30, we tested the effect of this ligand on cell growth and differentiation of the human breast cancer cells AU-565 and MDA-MB-453 (which overexpress erbB-2) and MCF-7 cells (which express low levels of this protooncogene). Ligand concentrations that inhibited growth in cells overexpressing erbB-2 induced apparent differentiation of cells with a more mature phenotype, i.e., with characteristics such as inhibited cell growth, altered cytoplasmic and nuclear morphology, and increased synthesis of milk components (casein and lipids). No significant effect of the ligand was observed in the human breast cancer cell line MCF-7. Concomitant with the induction of differentiation in AU-565 and MDA-MB-453 cells, the erbB-2 protein was translocated from membrane to the cytoplasm and perinuclear sites. These findings indicate that ligand-induced growth inhibition in cells overexpressing erbB-2 is associated with an apparent induction of differentiation.

Post-recurrence survival was examined in 62 breast cancer patients who had undergone curative radical mastectomies between 1974 and 1976 and suffered recurrences within 127 months of surgery. The prognostic value of 11 clinical, histological and genetic factors, including histologic grade of malignancy and amplification of oncogenes was analyzed using univariate and multivariate analyses. Not only the site of first recurrence, clinical stage and size of primary tumor at initial surgery, and disease-free period, but also histologic grade and amplification of the c-erbB-2 proto-oncogene were significant prognostic indicators of recurrent breast cancer. Multivariate analysis using Cox s regression model, histologic grade and amplification of c-erbB-2 in the primary tumor, as well as clinical stage at surgery and site of first recurrence, were shown to be major independent prognostic factors of recurrent breast cancer. Because post-recurrence prognosis was strongly influenced by the clinical, histological and genetic status of the primary breast cancer, appropriate evaluation of the primary tumor for the grade of aggressiveness of the cancer cells, as well as the extent of cancer spread, seem to be important.

c-erbB2/neu is a transforming oncogene that encodes a 185-kDa transmembrane glycoprotein. In many but not ALL studies, amplification and/or overexpression of the human c-erbB2/neu oncogene has been correlated with poor prognosis and the number of lymph node metastases in node-positive breast cancer patients. We have shown that expression of the activated rat c-erbB2/neu oncogene in mouse embryo fibroblast 3T3 cells is sufficient to induce experimental metastases in nude mice. Important steps in the metastatic event are tumor cell adhesion to endothelial cells and invasion of basement membranes. Therefore, we further examined the ability of c-erbB2/neu oncogene-transformed 3T3 cells to adhere to microvessel endothelial cells and secrete basement membrane-degradative enzymes. The c-erbB2/neu oncogene-transformed 3T3 cells were shown to be more adherent and have higher gelatinase activities. Since we had previously shown that the adenovirus 5 E1A gene product can suppress c-erbB2/neu-induced transformation of 3T3 cells, we examined the possibility that E1A can abrogate the metastatic properties of c-erbB2/neu-transformed 3T3 cells. We found that introduction of the E1A gene into c-erbB2/neu-transformed 3T3 cells reduced the formation of experimental metastatic tumors and inhibited metastasis-associated properties, such as adhesion to microvessel endothelial cells, migration through a layer of reconstituted basement membrane (Matrigel) and secretion of basement membrane-degradative enzymes. The results indicate that the mechanism by which the c-erbB2/neu gene induces higher metastatic potential is to promote adhesion and invasion steps of the metastatic cascade. The E1A gene, which functions by inhibiting these steps, is thus a suppressor gene for c-erbB2/neu-induced experimental metastasis.

Thirteen sebaceous gland carcinomas and 10 sweat gland carcinomas were examined to elucidate any important histological parameters influencing their prognosis, and the relationship between immunohistochemical expressions of c-erbB-2 oncoprotein and survival of the patients was analyzed. Sebaceous gland carcinomas with vacuolated cytoplasm in more than 50% of whole tumor area, with necrosis, and without lymphoid cell infiltration in tumor nests and stroma had a higher incidence of tumor recurrence and tumor-related death than tumors with vacuolated cytoplasm in 50% or less of whole tumor area (p < 0.01), without necrosis, and with lymphoid cell infiltration in tumor nest and stroma (p < 0.05). Sweat gland carcinomas of ALL cases with fatal outcomes demonstrated tubular differentiation in 20% or less of whole tumor area, lymphatic permeation and desmoplastic reaction. Three sebaceous gland carcinomas and three sweat gland carcinomas were positive for c-erbB-2 oncoprotein. Two of three sebaceous gland carcinomas, and ALL three sweat gland carcinomas developed tumor recurrence and ended in tumor-related deaths. Sweat gland carcinomas with c-erbB-2 expression had significantly shorter survival than those with negative immunostain (p < 0.01). Cytoplasmic appearance, tumor necrosis, and lymphoid cell infiltration in tumor nests and stroma of sebaceous gland carcinoma, and tubular differentiation, lymphatic permeation, and growth patterns of sweat gland carcinoma are considered to closely correlate to the prognosis. Immunohistochemically detected c-erbB-2 oncoprotein may be an indicator of bad prognosis.

BACKGROUND: It is unclear whether HER-2/neu proto-oncogene expression in ovarian epithelial neoplasms is related to prognosis. METHODS: The authors performed immunohistochemical stains on 20 serous tumors of low malignant potential (STLMP) in Stages I and II and 19 serious carcinomas in the same stages. They used three different commercial antibodies to make comparisons. RESULTS: Two of four Stage I STLMP in patients who experienced disease progression showed positive staining for the gene product, whereas none of seven Stage I nonprogressive STLMP showed positive staining. Five of the six Stage III nonprogressive STLMP showed positive staining, whereas none of three Stage III STLMP that progressed showed positive staining. Three carcinomas (one Stage I and two Stage III) also showed positive staining. CONCLUSIONS: expression of HER-2/neu may be associated with high stage in serous ovarian neoplasms, but it is not likely to identify the small fraction of patients with STLMP who will experience disease progression.

In ovarian cancers, no valuable prognostic factors are available so far for predicting biological behaviour and clinical outcome. During the last years, overexpression of c-erbB-2-oncogene has been reported to be a prognostic factor in various human carcinomas. Its prognostic value in ovarian cancer is still a matter of controversy. The records and histological specimens of 243 patients with primary ovarian cancer were reviewed. Overexpression of c-erbB-2-oncogene encoded transmembrane protein p185 was determined immunohistochemically using polyclonal and monoclonal antibodies. Of 243 investigated tumours, 45 (19%) were positive. We examined the relationship between p185 and clinical stage, histological type, grading and prognosis. p185 overexpression differs within the histological subtypes of tumours. No correlation was found between p185 overexpression and stage or histological grade. The follow-up data demonstrate that patients with positive staining for p185 have a significantly worse prognosis (p = 0.001) than those with negative staining. These results suggest that overexpression of c-erbB-2 oncogene is associated with higher biological aggressiveness and unfavourable course of disease.

An immunohistochemical study of c-erbB-2 oncoprotein expression was carried out on 201 cases of primary salivary gland tumors, using a polyclonal antibody, raised to the intracytoplasmic domain of the c-erbB-2 oncogene product. An intense membrane reactivity was observed in one case of sialocarcinoma transformed from pleomorphic adenoma (n = 8) and one case of mucoepidermoid carcinoma (n = 22). A comparative histopathologic evaluation of c-erbB-2 positive tumors showed marked variation in cell size, nuclear pleomorphism, multinucleation, a high mitotic rate and increased lymphoid cell infiltration and an aggressive clinical course with poor survival. The results indicate that c-erbB-2 oncoprotein is rarely expressed in malignant salivary gland tumors. However, the overexpression appears to have a distinct histopathologic feature, but a larger study incorporating histopathology and clinical data would be necessary to correlate the significance of c-erbB-2 oncogene product in salivary malignant tumors.

The c-erbB-2 mRNA was detected by the S1 nuclease protection assay and Northern blotting in breast cancer tissues. In contrast to the Northern blot analysis which has been used in ALL recent publications concerning c-erbB-2 expression on the level of RNA, the S1-nuclease protection assay has distinct advantages with respect to sensitivity, reproducibility, and handling of radioactive probes. We compared the expression of c-erbB-2 in 120 breast carcinomas which were operated in the years 1989-1990 on the level of the mRNA (S1 nuclease protection assay) and the protein (immunohistochemistry), respectively. In general, results obtained with both methods were in good agreement. Only minor differences in classification were observed with 18 samples, ALL of them belonging to either the moderate or the weak c-erbB-2 expression phenotype. In addition, the level of c-erbB-2-protein was investigated by immunohistochemistry in 271 breast carcinomas which were operated in the years 1984-1987. Comparison of the level of c-erbB-2 expression with the patient history indicates that patients whose tumors had already metastasized to the axillary nodes showed a reduced overall and disease-free survival in the group with pronounced expression of the c-erbB-2 protein. Thus the strong expression of c-erbB-2 oncogene in primary breast cancers appears to be an additional and particular prognostic factor in lymph node positive patients.

The c-erbB-2 mRNA was detected by the S1 nuclease protection assay and Northern blotting in breast cancer tissues. In contrast to the Northern blot analysis which has been used in ALL recent publications concerning c-erbB-2 expression on the level of RNA, the S1-nuclease protection assay has distinct advantages with respect to sensitivity, reproducibility, and handling of radioactive probes. We compared the expression of c-erbB-2 in 120 breast carcinomas which were operated in the years 1989-1990 on the level of the mRNA (S1 nuclease protection assay) and the protein (immunohistochemistry), respectively. In general, results obtained with both methods were in good agreement. Only minor differences in classification were observed with 18 samples, ALL of them belonging to either the moderate or the weak c-erbB-2 expression phenotype. In addition, the level of c-erbB-2-protein was investigated by immunohistochemistry in 271 breast carcinomas which were operated in the years 1984-1987. Comparison of the level of c-erbB-2 expression with the patient history indicates that patients whose tumors had already metastasized to the axillary nodes showed a reduced overall and disease-free survival in the group with pronounced expression of the c-erbB-2 protein. Thus the strong expression of c-erbB-2 oncogene in primary breast cancers appears to be an additional and particular prognostic factor in lymph node positive patients.

Immunoreactivity of the c-erbB-2 proto-oncogene product and nuclear DNA content were assessed in specimens from 211 breast cancer patients with a mean follow-up of 16 years (range 13-19 years). A routine immunoperoxidase technique was used and cytometrical DNA assessments were performed on cytodiagnostically identified tumour nuclei, using image analysis. C-erbB-2 cell membrane staining was observed in 29% of the cases and was found to be related to tumour size (P = 0.02), histopathological grade (P = 0.02) and nuclear DNA content (P < 0.01). In univariate analysis immunohistochemical c-erbB-2 expression was of prognostic significance among node-positive patients (P = 0.02), but not among women with node-negative disease. This prognostic ability was reduced by multivariate analysis and was no longer significant. In contrast, nuclear DNA content was significantly related to distant recurrence-free survival even in multivariate analysis after adjustment for nodal status and tumour size (P < 0.01). In conclusion, the findings of the present study indicate that c-erbB-2 expression is of limited prognostic value in a subgroup of patients, whereas nuclear DNA content seems to provide significant prognostic information even in node-negative patients.

HER-2/neu gene expression, DNA ploidy and proliferation index were studied in 250 cases of breast cancer. expression of HER-2/neu was determined by using an antibody to the HER-2/neu receptor. Ki-67 antibody was used to determine the proliferation index of the breast cancers, and the Feulgen method was used to assess DNA amounts in the tumor cells. Histochemical staining was quantitated by image analysis. Of the cancers studied, 72 were positive for overexpression of HER-2/neu protein; of these, 62 (86%) possessed near-tetraploid DNA content, and 47 (65%) had more than one G0G1 stem line (polyploid) of DNA distribution. Cells from the cases negative for HER/2-neu overexpression contained DNA amounts that ranged from diploid to varying degrees of aneuploid. A significant difference in the amounts of cellular proliferation in HER-2/neu overexpressing cancers was found between those that expressed the HER-2/neu receptor on their membranes and those that exhibited mainly cytoplasmic receptors.

Three hundred and one primary breast cancers from patients with tumor infiltrated lymph nodes were analyzed for the presence of HER-2/neu oncoprotein by two procedures: Western blot (WB) and immunohistochemistry (IHC). Overexpression of this protein was found by WB in 16.6% of the tumors, and by IHC in 16.3%. Concordance between the two methods was found in 95% of tumors (286/301). In 7 cases we found HER-2/neu by IHC but not by WB, while the opposite was found in the remaining 8 patients. This discrepancy was found mainly in samples with HER-2/neu values just above the cut points and were therefore close to the sensitivity limits of the procedures used here. This study helps to define the parameters that should be considered to evaluate the immunostaining for HER-2/neu as positive (i.e., membrane staining, IHC score of 2 or more). The results obtained by both techniques were correlated with several currently used prognostic factors. Higher HER-2/neu protein expression was found in tumors lacking estrogen or progesterone receptors, in tumors with high S-phase fraction and in patients with more than 3 positive lymph nodes. In contrast, no relationship was found between overexpression of this protein and tumor size, ploidy, or age of the patient. Patients with elevated HER-2/neu expression showed a significantly worse overall survival by both methods, IHC (p = 0.05) and WB (p = 0.001). In conclusion, there is very high agreement between IHC and WB when measuring expression of HER-2/neu and both techniques showed prognostic significance.

Three hundred and one primary breast cancers from patients with tumor infiltrated lymph nodes were analyzed for the presence of HER-2/neu oncoprotein by two procedures: Western blot (WB) and immunohistochemistry (IHC). Overexpression of this protein was found by WB in 16.6% of the tumors, and by IHC in 16.3%. Concordance between the two methods was found in 95% of tumors (286/301). In 7 cases we found HER-2/neu by IHC but not by WB, while the opposite was found in the remaining 8 patients. This discrepancy was found mainly in samples with HER-2/neu values just above the cut points and were therefore close to the sensitivity limits of the procedures used here. This study helps to define the parameters that should be considered to evaluate the immunostaining for HER-2/neu as positive (i.e., membrane staining, IHC score of 2 or more). The results obtained by both techniques were correlated with several currently used prognostic factors. Higher HER-2/neu protein expression was found in tumors lacking estrogen or progesterone receptors, in tumors with high S-phase fraction and in patients with more than 3 positive lymph nodes. In contrast, no relationship was found between overexpression of this protein and tumor size, ploidy, or age of the patient. Patients with elevated HER-2/neu expression showed a significantly worse overall survival by both methods, IHC (p = 0.05) and WB (p = 0.001). In conclusion, there is very high agreement between IHC and WB when measuring expression of HER-2/neu and both techniques showed prognostic significance.

The erb B2/neu oncogene encodes a protein which sequence is closely similar to the epidermal growth factor receptor (EGFR). We have previously found that EGF can induce the expression of erb B1/EGFR gene in normal and 3H-TdR transformed C3H/10T1/2CL8 mouse embryo fibroblast cells i.e. NC3H10 and TC 3H10 respectively, but we do not know whether the neu oncogene expression can be induced by EGF. In this study, the effect of EGF on NC3H10 and TC3H10 has been observed by Northern blot analysis. The result indicated that EGF had a obvious induction effect on neu oncogene expression in these cells. Thus, the expression of both erbB 1/EGFR gene and erbB 2/neu oncogene can be induced by EGF. This result may provide a novel clue to the molecular mechanism of EGF action in cell nucleus.

HER-2/ neu is an immunogenic protein eliciting both humoral and cellular immune responses in patients with HER-2/ neu-positive ((+)) tumors. Preexisting cytotoxic T lymphocyte (CTL) immunity to HER-2/ neu has so far been mainly evaluated in terms of detection of CTL precursor (CTLp) frequencies to the immunogenic HLA-A2-binding nona-peptide 369-377 (HER-2(9(369))). In the present study, we examined patients with HER-2/ neu(+) breast, ovarian, lung, colorectal, and prostate cancers for preexisting CTL immunity to four recently described HER-2/ neu-derived and HLA-A2-restricted "cytotoxic" peptides and to a novel one spanning amino acids 777-785 also with HLA-A2-binding motif. We utilized enzyme-linked immunosorbent spot (ELISpot) assay, which allows a quantitative and functional assessment of T cells directed against specific peptides after only brief in vitro incubation. CTL reactivity was determined with an interferon gamma (IFN-gamma) ELISpot assay detecting T cells at the single cell level secreting IFN-gamma. CTLp were defined as peptide-specific precursors per 10(6) peripheral blood mononuclear cells (PBMCs). Patients PBMCs with increased CTLp were also tested against autologous tumor targets and peptide-pulsed dendritic cells (DCs) in cytotoxicity assays. We also studied patients with HER-2/ neu-negative ((-)) tumors and healthy individuals. Of the HER-2/neu(+) patients examined, 31% had increased CTLp to HER-2(9(952)), 19% to HER-2(9(665)), 16% to HER-2(9(689)), and 12.5% HER-2(9(435)), whereas only 2 of 32 patients (6%) responded to HER-2(9(777)). The CTLp recognizing HER-2(9(952)) were extremely high in two patients with breast cancer, one with lung cancer, and one with prostate cancer. None of the HER-2/neu(-) patients or healthy donors exhibited increased CTLp to any of these peptides. Besides IFN-gamma production, preexisting CTL immunity to ALL five HER-2/ neu peptides was also shown in cytotoxicity assays where patients PBMCs with increased CTLp specifically lysed autologous tumor targets and autologous peptide-pulsed DCs. Our results demonstrate for the first time that (1) preexisting immunity to peptides HER-2(9(435)), HER-2(9(952)), HER-2(9(689)), HER-2(9(665)), and HER-2(9(777)) is present in patients with HER-2/ neu(+) tumors of distinct histology, (2) HER-2(9(777)) is a naturally processed peptide expressed on the surface of HER-2/ neu(+) tumors, as are the other four peptides, and (3) HER-2/ neu(+) prostate tumor cells can be recognized and lysed by autologous HER-2 peptide-specific CTL. Our findings broaden the potential application of HER-2/ neu-based immunotherapy.

expression of epidermal growth factor receptor (EGFR) and ERBB2 oncoprotein were studied in paraffin-embedded normal (n = 2), hyperplastic (n = 17), and malignant (n = 147) prostatic tissues by immunohistochemistry. Strong immunoreactivity was detected in the epithelial cells of ALL normal and hyperplastic prostates with a new EGFR antibody (Mab31G7). In prostatic carcinomas, the EGFR immunoreactivity was variable with 47% showing uniform, 39% partial, and 14% no staining. tumors with partial or uniform EGFR immunoreactivity were locally more advanced and of higher histological grade than the EGFR-negative tumors. EGFR-positive tumors also had two to three times higher S-phase fraction, suggesting that EGFR expression conferred proliferative advantage. Patients who had either partially or uniformly EGFR-positive carcinomas had a worse 10-yr progression-free (p = 0.05), overall (p = 0.03), and prostatic carcinoma-specific (p = 0.007) survival than those with EGFR-negative carcinomas. However, according to a multivariate analysis, EGFR did not have independent prognostic value. None of the normal, hyperplastic, or malignant prostate tissues showed clearly positive ERBB2 immunoreactivity with MAb1 antibody.

The over-expression of the proto-oncogene HER-2 (c-erbB-2/neu) in ovarian, endometrial and mammary carcinoma is an important indicator for poor prognosis. We have previously shown in 3 out of 4 ovarian carcinoma cell lines an interferon-gamma (IFN-gamma)-mediated reduction in HER-2 specific protein and RNA levels. The oncogene expression was lowered only in the ovarian carcinoma cell lines but not in 3 IFN-gamma-sensitive human breast cancer cell lines. We extended our observations also to IFN type I, alpha and omega. The expression of the oncogene was measured by both the p185HER-2 ELISA and in selected cases by a living cell radioimmunoassay using the monoclonal antibody (MAb) 4D5 against the extracellular domain. Both IFN types reduced the expression of HER-2 in the ovarian carcinoma cell lines OVCAR-3, HTB-77, 2774 and SKOV-6, and in the SKUT-2 endometrial carcinoma cells. In contrast, SKOV-8 human ovarian carcinoma cells were sensitive for both IFN types regarding proliferation, but only IFN-gamma reduced proto-oncogene expression. In the SKBR-3 human mammary carcinoma cells, neither IFN type had an effect on HER-2 expression. The antibodies 4D5, 7C2, 3E8, and 3H4 which bind to the extracellular domain of p185HER-2 protein specifically inhibited anchorage-independent growth of SKBR-3 and HTB-77 cells. expression of the oncogene HER-2 is the leading prognostic factor in ovarian cancer. Its modulation might represent a mechanism by which IFNs inhibit cell proliferation.

The neu gene, which encodes a putative tyrosine kinase growth factor receptor termed p185neu, was originally identified as a dominant transforming gene in neurogliomas and schwannomas induced by transplacental treatment of rat embryos with ethylnitrosourea. The present studies were undertaken to determine the expression pattern of the neu gene in peripheral nerve. Northern blot analysis of total RNA isolated from rat sciatic nerves demonstrated prominent neu mRNA expression on postnatal days 1 and 7, with substantially lower expression up to adulthood. Immunohistochemical studies confirmed expression of p185neu by Schwann cells (SC) in developing sciatic nerve and minimal p185neu immunoreactivity in adult nerves. However, neu mRNA and p185neu protein progressively increased following sciatic nerve transection in adult animals. In addition, neu mRNA and p185neu were found in neonatal rat sciatic nerve SC and several SC-derived cell lines. In resting SC, neu mRNA was expressed at a low level, but was greatly increased by treatment with forskolin and glial growth factor. These studies demonstrate that the neu gene and its protein product, p185neu, are expressed by SC both in vivo and in vitro and suggest that p185neu plays a role in the regulation of SC proliferation or differentiation.

The value of morphometry, DNA flow cytometry and HER-2/neu oncoprotein expression for prediction of response to adjuvant chemotherapy in premenopausal lymph node positive breast cancer patients was evaluated in a group of CMF treated patients and controls with long-term follow-up. In the treated group, the Morphometric Prognostic Index (cutpoint 1.1) was the best prognosticator (p less than 0.0001, MC = 16.9), followed by the Mitotic Activity Index, the volume percentage epithelium and the number of positive nodes. For the controls, only the % HER-2/neu oncoprotein expression revealed significant differences (p less than 0.0001, MC = 16.3). When directly comparing treated patients and controls stratified for a certain parameter, no significant differences were obtained, although a trend towards improved survival in the treated group was present for some of the subgroups for several parameters. These preliminary results indicate that morphometric features and quantitative HER-2/neu oncoprotein expression may be important factors for identifying cases that will or will not respond to adjuvant chemotherapy.

The c-erbB-2 proto-oncogene encodes a transmembrane protein which is homologous to the epidermal growth factor receptor. This protein can be localized immunohistochemically in formalin-fixed paraffin-embedded material using a monoclonal antibody NCL-CB11; positive membrane staining correlates with gene amplification and protein overexpression in breast cancer. Using this technique we have shown that only 2/26 (8%) of hepatocellular carcinomas, 0/10 (0%) of cholangiocarcinomas and 0/2 (0%) hepatoblastomas overexpressed c-erbB-2 as evidenced by membrane staining. Moreover c-erbB-2 mRNA was not detected in seven hepatocellular carcinomas examined by Northern blot analysis. c-erbB-2 overexpression is, therefore, unlikely to be contributing to the malignant phenotype in hepatocellular carcinoma and cholangiocarcinoma.

The oncogene HER-2/neu encodes a transmembrane glycoprotein of 185 kDa (gp185HER-2) with tyrosine-kinase activity. Gene amplification and high levels of expression of gp185HER-2 have been found to correlate with poor clinical outcome in breast and ovarian carcinomas. Employing a somatic cell hybrid fusion protocol, which yields a high frequency production of hybridomas, we have analyzed the extent of the murine immune response to the gp 185 extracellular domain. In a single fusion experiment, using as immunogen NIH 3T3 cells expressing high levels of a transfected human HER-2 gene, we have generated mAbs, mainly of IgG1 isotype, displaying high affinity (10(7)-10(10) mol/L) to gp 185. Analysis of the epitope specificity has allowed the identification of five distinct groups of spatially related epitopes, each provided with different immunodominancy, and ALL resistant to formalin fixation. The use of inhibitor of N-linked glycosylation tunicamicyn has demonstrated that the mAbs bind to epitopes localized in the protein core of gp185HER-2. Because recent reports have shown that gp185HER-2 has a restricted expression in normal tissues and is homogenously detectable in metastatic foci of gp 185 + primary tumors, antibodies to this macromolecule, in addition to their prognostic value, may represent reagents for in vitro and in vivo diagnostic applications, as well as for the development of therapeutic strategies.

BACKGROUND: The HER-2/neu oncogene and its p185 receptor protein are indicators of a more aggressive form of breast cancer. HER-2/neu status guides Herceptin therapy, specifically directed to the extracellular domain (ECD) of the HER-2/neu oncoprotein. The HER-2/neu ECD is shed from cancer cells into the circulation and is measurable by immunoassay. METHODS: We performed a systematic review of the peer-reviewed literature on circulating ECD with respect to prevalence, prognosis, prediction of response to therapy, and monitoring of breast cancer. RESULTS: The prevalence of increased ECD in patients with primary breast cancer varied between 0% and 38% (mean, 18.5%), whereas in metastatic disease the range was from 23% to 80% (mean, 43%). Some women with HER-2/neu-negative tumors by tissue testing develop increased ECD concentrations in metastatic disease. Increased ECD has been correlated with indicators of poor prognosis, e.g., overall survival and disease-free survival. Increased ECD predicts a poor response to hormone therapy and some chemotherapy regimens but can predict improved response to combinations of Herceptin and chemotherapy. Many studies support the value of monitoring ECD during breast cancer progression because serial increases precede the appearance of metastases and longitudinal ECD changes parallel the clinical course of disease. CONCLUSIONS: The monitoring of circulating HER-2/neu ECD provides a tool for assessing prognosis, for predicting response to therapy, and for earlier detection of disease progression and timely intervention with appropriate therapy.

Immunohistochemical (IHC) HER-2/neu protein overexpression was found in 17.6% of canine mammary gland carcinomas, a percentage similar to that observed in human breast carcinoma, but there was no gene amplification by chromogenic in situ hybridization (CISH). Canine mammary carcinoma would be a suitable natural model of that subset of human breast carcinomas with HER-2 protein overexpression without gene amplification.

The bcl-2 gene codes for a protein which functions to inhibit apoptotic cell death, that involves an intrinsic normal cell death program. Bcl-2 overexpression was originally described in a follicular lymphoma, but more recently bcl-2 expression has been observed in a variety of other human neoplasms. Variation in the frequency of apoptosis in hormone-sensitive tissues, such as the endometrium, is known to occur as a result of hormonal changes in both physiological and pathological circumstances. In this study we examined bcl-2 protein expression in a total of 170 samples of endometrial tissues (18 proliferative endometrium, 14 secretory endometrium, 35 adenomatous hyperplasia and 103 carcinomas). The results were compared with p53, pRb and c-erbB-2 proteins expression, estrogen and progesterone receptors status, with the proliferative activity and with clinicopathological features. The expression of bcl-2 protein was lower in the group of carcinomas, when compared with the cases of adenomatous hyperplasia (p < 0.0001), normal proliferative (p < 0.0001) and secretory endometrium (p = 0.07). In normal proliferative endometrium bcl-2 expression was correlated with PCNA (p = 0.026) and in secretory endometrium it was correlated with ER status (p = 0.042). In hyperplasias, bcl-2 was correlated with PCNA (p = 0.019) and the PR (p = 0.007) expression. In carcinomas, decreased bcl-2 expression was associated with increased tumor grade (p = 0.04). A positive relationship between bcl-2 expression and pRb, as well as PCNA score (p = 0.014 and p = 0.001, respectively), was also found. These results indicate that bcl-2 expression may play a role in the inhibition of apoptosis in endometrial carcinoma and its expression seems to be associated with tumor differentiation and cell proliferation.

OBJECTIVE: To detect the relations of c-erbB-2 oncogene protein, epidermal growth factor receptor (EGFR) and transforming growth factor-beta1 (TGF-beta1) to the progression or metastasis of pancreatic carcinoma. METHODS: Using streptavidinbiotin complex (SABC) method, c-erbB-2 oncongene protein, we examined immunohistochemically EGFR and TGF-beta1 expressions in wax-tissue sections from 10 individuals with normal pancreas (NP), 13 patients with chronic pancreatitis (CP) and 36 patients with pancreatic ductal adenocarcinoma (PC). RESULTS: The positive expression rates of c-cerbB-2 oncogene protein, EGFR and TGF-beta1 in the NP, CP and PC groups were 0, 0, 10%; 7.7%, 7.7%, 7.7%; and 41.7%, 50.0%, 44.4%, respectively. The positive expression rates of the three specific proteins increased more significantly in the PC group than in the NP and CP groups (P<0.05). The individual expression of c-erbB-2, EGFR and TGF-beta1 was not related to the age and sex of the patients as well as the site, size and histopathological grade of tumors (P>0.05), but to the clinical stage of tumors (P<0.01). The coexpression rate of the three proteins was 27.8% (10/36). This coexpression in the PC group was correlated with the histopathological grades and clinical stages of tumors (P<0.01). CONCLUSION: Detection of c-erbB-2 oncogene protein, EGFR, and TGF-beta1 expressions in pancreatic tissue is helpful to judge the malignancy, progression, and metastasis of PC.

Breast cancer patients with HER-2/neu oncogene amplification by fluorescence in situ hybridization (FISH) have been shown to have a better response to trastuzumab (Herceptin) therapy than those showing HER-2/neu protein overexpression only. Many centers currently perform FISH only on tumors showing 2+ HER-2/neu positivity by immunohistochemistry (IHC), with the assumption that 3+ positivity virtually equates with amplification. Results of FISH performed on 102 breast cancer cases over a 12-month period were correlated with HER-2/neu IHC results. FISH was performed using a ratio of HER-2/neu and chromosome 17 centromere signal counts (PathVysion; Vysis, Downers Grove, IL). Immunohistochemical expression of HER-2/neu was evaluated according to the published scoring guidelines of the HercepTest (Dako, Carpinteria, CA). Only 22 of 45 tumors with 3+ positivity (49%) showed amplification by FISH. Only 2 of 25 cases with 2+ staining by IHC (6%) showed gene amplification, and 1 of 25 cases with negative IHC staining (4%) showed weak amplification. Of the 25 cases showing oncogene amplification, 22 (88%) showed 3+ IHC positivity, 2 (8%) showed 2+ positivity, and 1 (4%) was negative by IHC. More than 50% of breast tumors showing strong 3+ HER-2/neu staining do not show oncogene amplification by FISH. Most tumors with 2+ and negative IHC also fail to amplify. In our experience, FISH studies should be performed on ALL 3+ and 2+ staining tumors to avoid inappropriate and toxic treatment. The decision to perform FISH on IHC-negative tumors should be guided by additional parameters, including tumor grade and estrogen receptor status.

The histogenesis as well as the biological and molecular differences in mammary Paget s disease (MPD) and extramammary Paget s disease (EPD) are not well understood. HER-2/neu oncogene overexpression is associated with poor prognosis in breast cancer patients. It is also believed that the spread of Paget s cells through the epidermis is induced by a motility factor that acts via the HER-2/neu receptor. However, previous studies on HER-2/neu expression in MPD and EPD have given conflicting results. Recent studies have suggested that vimentin expression in breast cancer confers a more aggressive phenotype with a possible role in tumor invasion and metastasis. We examined 58 cases of MPD and EPD for HER-2/neu overexpression and vimentin status to study the role of these markers in the production of the Paget s phenotype. Thirty-five of the 38 cases (92.1%) of MPD were associated with an underlying carcinoma, while none of the cases of EPD were associated with an underlying malignancy. Thirty-six of the 38 cases of MPD (94.7%) overexpressed the HER-2/neu oncoprotein and 17 cases (44.7%) showed vimentin expression. In contrast, only 1 of the 20 cases of EPD (5%) showed positivity for HER-2/neu oncoprotein and ALL were negative for vimentin. Our results indicate that the cell motility enhancing effect of HER-2/neu oncoprotein and possibly vimentin plays a significant role in the pathogenesis of MPD which appears to be a pagetoid spread of an underlying ductal malignancy (secondary), while EPD is an in situ malignant transformation of a totipotential epidermal cell or glandular epithelium.

PURPOSE: Esophageal carcinoma is a challenging target for radiotherapy. To improve treatment efficacy, an investigation of a predictive factor is desirable. In this study, we evaluated the significance of apoptosis and immunohistochemical staining for p53, Ki-67, c-erbB-2 (HER-2/neu), Ku (p70/p80), and DNA-PKcs for predictive markers of the responsiveness to chemoradiotherapy in esophageal squamous cell carcinoma. MATERIALS AND METHODS: This retrospective analysis consisted of 34 patients with esophageal squamous cell carcinoma in whom tumor biopsy was performed before treatment. They were divided into chemoradiosensitive (n = 13) and chemoradioresistant (n = 21) groups according to the tumor response evaluated at a total radiation dose of 40 Gy. The biopsy samples were examined with immunohistochemical staining for various factors and with an in situ nick end labeling method for apoptosis. The examined data were compared between the two groups. RESULTS: The difference in the Ki-67, p53, Ku (p70/p80), DNA-PKcs labeling indexes and the apoptosis index in tumor cells between the chemoradiosensitive and chemoradioresistant groups was not statistically significant. The expression of c-erbB-2 oncoprotein was statistically significant in the chemoradioresistant group (p = 0.02), although it did not correlate with survival. CONCLUSIONS: c-erbB-2 immunostaining is useful for the prediction of chemoradioresistance in esophageal squamous cell carcinoma.

Interferon (IFN) regulatory factor-1 (IRF-1) is a transcription factor that has been historically associated with type I IFN activation and antioncogenic properties. We studied IRF-1 expression and DNA-binding capacity in nontransformed and transformed mouse fibroblasts. A 43-kDa nuclear IRF-1 protein was expressed biphasically during the cell cycle in primary mouse embryo fibroblasts, nontransformed NIH 3T3 cells, and ras revertants. IRF-1 expression became constitutive in ras-transformed NIH 3T3 cells and in cells transformed by oncogenes ets, fes, fos, her-2/neu, met, mos, raf, or trk, suggesting that deregulated IRF-1 expression may be associated with loss of growth control. Lysyl oxidase (LO), a ras suppressor that is downregulated in ras transformants, is an IRF-1 target gene, but it is not stimulated by abundant IRF-1 present in transformants, while another IRF-1 target gene (iNOS) is transcribed. IRF-1 from either normal or ras-transformed cells bound to IRF elements in the IFN-beta and LO promoters. IRF-1 in transformants can, therefore, bind to but not transactivate the LO promoter, and the presence of IRF-1 is not sufficient to suppress ras transformation. LO expression may effect the regulated expression of IRF-1: a ras revertant, which was generated by stable transfection of LO cDNA, regained the normal biphasic IRF-1 pattern. A mainly cytoplasmic, constitutively expressed 46-kDa protein with immunologic identity to the 43-kDa nuclear IRF-1 was also present in normal and transformed cells, but as it did not bind to the IRF elements, its function is unclear.

PURPOSE: To evaluate the frequency of ERBB2, INT2 and CMYC oncogene amplifications and their coexistence with PTEN gene mutations in endometrial carcinomas. METHODS: In 54 endometrial carcinomas amplification of ERBB2, INT2 and CMYC was determined using differential polymerase chain reaction (dPCR), and mutations in ALL exons of PTEN were investigated by PCR-SSCP and direct sequencing methods. Results were correlated with clinicopathological features of tumors. RESULTS: In 31 out of 54 endometrial carcinomas (57.4%) genetic defects were found within the examined genes. Of ALL identified defects, mutations in PTEN and the amplification of CMYC were most frequent (26/54-48.1% and 10/54-18.5%, respectively). INT2 was amplified in 5.6% (3/54) of cases. In no case did we find ERBB2 amplification. In 77.4% (24/31) of cases only one gene was damaged. Of these, 20 cases showed only PTEN mutations, three cases only CMYC, and one case only INT2 amplification. In another seven out of 31 tumors (22.5%) defects in two or three genes coexisted simultaneously: PTEN and CMYC in five cases, CMYC and INT2 in one case, and PTEN, CMYC, and INT2 in one case. We found a number of interesting relations between the location of mutations within the PTEN sequence and the presence (+) or lack (-) of CMYC amplification. In the PTEN+CMYC- tumors the PTEN mutations were most frequent in exons 1-5, and less frequent in exons 7-8 (66.7% and 33.3%, respectively). In contrast, in the PTEN+CMYC+ carcinomas the PTEN mutations were found mainly in exons 7-8 (85.7%). PTEN mutations were equally frequent in both early and more advanced endometrial carcinomas. The CMYC amplification, however, was more frequent in advanced as compared to early tumors, although this difference did not reach statistical significance. CONCLUSIONS: Our data suggest that differences in the presence of genetic defects may reflect the different molecular pathways of endometrial carcinogenesis. These data also suggest that location of intragenic PTEN mutations and their coexistence with the CMYC amplification may play a crucial part in the development of various subtypes of endometrial carcinoma, but this preliminary suggestion requires further research.

BACKGROUND: Studies of Her-2/neu protein expression in interval and screen-detected breast cancers have been conflicting. Therefore we assessed the Her-2/neu amplification status in these groups by using in situ hybridization. PATIENTS AND METHODS: The Her-2/neu oncogene amplification and protein over-expression were compared in 79 screen-detected and 39 interval breast carcinomas, using a novel and well-documented chromogenic in situ hybridization (CISH) method and immuhistochemistry. RESULTS: There were 33% CISH-positive cases in the interval cancer group and only 4% CISH-positive cases in the screen-detected group. The odds ratio for interval cancer was 14.1 (95% CI 2.2 to 91.0) in the CISH-positive tumours compared with CISH-negative tumours after adjustment for nodal status, tumour size and histological grade. CONCLUSION: Our results indicate, for the first time, that there is a clear-cut difference in Her-2/neu amplification between screen-detected and interval breast carcinomas. The amplification appears to be a rare event in screen-detected cancers but distinctly frequent in interval cancers when compared to cancers described in earlier studies.

One hallmark of tumor formation is the transcriptional upregulation of human telomerase reverse transcriptase, hTERT, and the resultant induction of telomerase activity. However, little is presently understood about how hTERT is differentially activated in tumor cells versus normal somatic cells. Specifically, it is unclear if oncoproteins can directly elicit hTERT expression. To this end, we now show that three oncoproteins, HER2/Neu, Ras, and Raf, stimulate hTERT promoter activity via the ETS transcription factor ER81 and ERK mitogen-activated protein (MAP) kinases. Mutating ER81 binding sites in the hTERT promoter or suppression of ERK MAP kinase-dependent phosphorylation of ER81 rendered the hTERT promoter unresponsive to HER2/Neu. Further, expression of dominant-negative ER81 or inhibition of HER2/Neu significantly attenuated telomerase activity in HER2/Neu-overexpressing SKBR3 breast cancer cells. Moreover, HER2/Neu, Ras, and Raf collaborated with ER81 to enhance endogenous hTERT gene transcription and telomerase activity in hTERT-negative, nonimmortalized BJ foreskin fibroblasts. Accordingly, hTERT expression was increased in HER2/Neu-positive breast tumors and breast tumor cell lines relative to their HER2/Neu-negative counterparts. Collectively, our data elucidated a mechanism whereby three prominent oncoproteins, HER2/Neu, Ras, and Raf, may facilitate tumor formation by inducing hTERT expression in nonimmortalized cells via the transcription factor ER81.

AIMS: c-erbB-2 expression has been found to be an important prognostic parameter in various types of tumors, but the role played by this oncoprotein in thyroid tumors is still controversial. This study is designed to investigate c-erbB-2 expression in different types of thyroid tumors. METHODS: c-erbB-2 protein over-expression was studied immunohistochemically (IHC) in 68 paraffin-embedded thyroid tumors (12 follicular adenomas, 20 papillary carcinomas, 20 follicular carcinomas, eight medullary carcinomas, eight anaplastic carcinomas), diagnosed at the Pathology Department of Cukurova University. RESULTS: No expression of c-erbB-2 was found in anaplastic carcinomas, but 50% of the papillary carcinomas showed a cytoplasmic staining pattern and 45% had a mixed staining pattern (cytoplasmic and membranous patterns). Eight (40%) of the 20 follicular carcinomas showed a mixed cytoplasmic/membranous staining pattern and three (15%) showed only cytoplasmic reactivity. Cytoplasmic immunoreactivity was detectable for c-erbB-2 in six out of eight (75%) medullary carcinomas. Finally, seven cases of 12 (58%) follicular adenomas showed cytoplasmic staining. CONCLUSIONS: Investigation of the exact role of c-erbB-2 in thyroid tumors requires further studies, and the different patterns of immunostaining may be helpful for determination of prognosis as is the case in breast carcinoma.

HER-2/neu (also known as HER2 or c-erb-B2) is a 185-kDa protein receptor with tyrosine kinase activity and extensive homology to the epidermal growth factor (EGF) receptor. HER-2/neu is expressed in many epithelial tumors and known to be overexpressed in approximately 20-25% of ALL ovarian and breast cancers, 35-45% of ALL pancreatic adenocarcinomas, and up to 90% of colorectal carcinomas. HER-2/neu overexpression represents a marker of poor prognosis. HER-2/neu-positive tumor cells are potentially good targets for tumor-reactive cytotoxic T lymphocytes which have been utilized in immunotherapeutic trials. In addition, the "humanized" monoclonal antibody Herceptin has been tested in several clinical trials and proved to be an effective adjuvant therapy for HER-2/neu-positive breast and ovarian cancers. Vaccinations aiming at generating T-cell responses are being examined in both experimental and clinical trials. Natural immunity at the level of T and B cells has been observed in patients with HER-2/neu-positive tumors confirming the immunogenicity of HER-2/neu and encouraging vaccination trials with HER-2 protein-derived subunits or synthetic peptides. This review summarizes recent data from patients with various types of HER-2/neu-overexpressing cancers carrying different HLA alleles and exhibiting preexistent immunity to HER-2/neu-derived synthetic peptides. It also discusses potential advantages of the various vaccination approaches to immunotherapy targeting the HER-2/neu molecule.

We have previously shown that BCR/ABL, a fusion protein generated by the t(9;22)(q34;q11) translocation found in the vast majority of chronic myelogenous leukemia (CML), cooperates with AML1/MDS1/EVI1 (AME), a fusion transcription factor generated by a t(3;21)(q26;q22) translocation identified as a secondary mutation in some cases of CML during the blast phase (CML-BC), in the rapid induction of an acute myelogenous leukemia (AML) in mice. In this study, we evaluated the leukemogenic potential of EVI1-, MDS1/EVI1- and AML1-related oncoproteins (AML1Delta, AML1/MDS1). We found that ectopic expression of either EVI1 or MDS1/EVI1 impaired hematopoiesis. However, neither EVI1 nor MDS1/EVI1 was sufficient for inducing AML in mice, although EVI1 did induce some hematologic neoplasia other than AML with a low efficiency. In addition, unlike AME, none of the EVI1- or AML1-related oncoproteins examined were capable of fully cooperating with BCR/ABL in the induction of AML. The results indicate that both the AML1 and EVI1 oncogenic components are required for the leukemogenic potential of AME and for the cooperation of AME and BCR/ABL in the induction of AML.

Vascular endothelial growth factor C (VEGF-C) is an important growth factor that governs lymphatic spread and the development of intraperitoneal tumors associated with epithelial ovarian cancer; however, its regulation is not yet understood. Overexpression of Her-2/NEU is related to poor survival in advanced epithelial ovarian carcinoma patients. Accordingly, this study attempted to analyze the association between the Her-2/NEU oncogene and VEGF-C in ovarian carcinoma and to elucidate the molecular mechanism of VEGF-C induction by Her-2/NEU. Immunohistochemistry was used to determine the expression of Her-2/NEU and VEGF-C in tissues from 41 patients with epithelial ovarian carcinoma. Several Her-2/NEU-stably-transfected Caov-3 ovarian carcinoma cells were used to evaluate the effect of Her-2/NEU on VEGF-C, the possible regulation mechanism, and the biological function of VEGF-C. Our experimental results identified a significant association between the Her-2/NEU oncogene and VEGF-C expression in both epithelial ovarian cancer patients (p < 0.05; Fishers exact test) and in vitro cell lines. The overexpression of Her-2/NEU in Caov-3 ovarian cancer cells resulted in induction of a considerable amount of VEGF-C mRNA and protein; this process was dose-dependently inhibited by herceptin. The generation of VEGF-C significantly increased endothelial permeability. Pharmacological and genetic inhibition assays revealed that the cytoplasmic signaling molecule, p38 MAPK, and the transcriptional factor, NF-kappa B, are critically involved in the transcriptional activation of the VEGF-C gene by Her-2/NEU. In conclusion, this work clearly establishes that the Her-2/NEU oncogene is essential for the regulation of VEGF-C in ovarian carcinoma. It may be possible to use the monoclonal antibody targeting Her-2/NEU receptor to limit the formation of malignant ascites and lymphatic spread in ovarian carcinoma.

BACKGROUND: Molecular cytogenetics of oncogene HER-2 amplification in primary hepatocellular carcinoma (HCC) is still unknown. The aim of this study was to investigate the frequency of HER-2 oncogene amplification in primary HCC and its relations to clinicopathological parameters and prognosis. METHODS: Forty-two surgical samples from patients with primary HCC were detected for their HER-2 oncogene amplification. The number of chromosome 17 and their ratio were tested by dual fluorescence in situ hybridization (FISH) technique, and then the correlations between HER-2 amplification, clinicopathological characteristics and prognosis were analyzed statistically. RESULTS: HER-2 oncogene amplification was detected in 9 (21.4%) of the 42 primary HCCs, including 4 patients with high copy (HC) (9.5%) and 5 patients with low copy (LC) (11.9%). HER-2 amplification was associated significantly with tumor size and postoperative survival time of HCC patients (P<0.05), and the presence of HER-2 gene amplification was correlated with postoperative relapse (P=0.257), but not related to sex, age, AFP level, HBV infection, histopathological grading and clinical staging of HCC patients (P>0.05). The HER-2 oncogene copy was examined in 31 (73.8%) of the 42 primary HCCs, consisting of 9 patients with HER-2 amplification (21.4%) and 22 patients with aneuploidy (52.4%). No significant relations were observed between the HER-2 oncogene copy, patient sex, tumor size, histopathological grading, clinical staging, postoperative relapse and survival time (P>0.05); but the HER-2 oncogene copy was correlated significantly to age, AFP level and HBV infection (P<0.05). CONCLUSIONS: There are a lower frequency of HER-2 oncogene amplification and a higher frequency of chromosome 17 aneuploidy in primary HCC. HER-2 oncogene amplification may be involved in the development and progression of large HCC in some patients, and seems to be a valuably independent prognostic factor predicting the recurrence and poor survival in patients with large HCC.

We have previously shown that mammary epithelial specific expression of the activated erbB2 allele under the control of the endogenous promoter in mice resulted in the formation of mammary adenocarcinomas. To assess whether mammary tumorigenesis in this model is influenced by the developmental window of expression, we generated mice that expressed the activated erbB2 allele in the germ line. Although we were able to derive viable transgenic mice that were heterozygous for the activated erbB2 allele, mice homozygous for the activated erbB2 allele died at 12.5 days of embryogenesis. These two separate lines of mice expressed activated erbB2 at equal levels in the mammary gland. Surprisingly, unlike the tumor-prone mice expressing activated ErbB2 in the mammary epithelium, mice with the germ-line erbB2 allele failed to develop tumors. Gene expression analysis of the preneoplastic mammary glands revealed that there were a number of luminal epithelial markers expressed at higher levels in the tumor-prone mice. These data suggest either an expansion of a susceptible population in the tumor-prone mice or the loss of this population in the tumor-resistant mice. Taken together, these observations suggest that the temporal pattern of expression of activated ErbB2 is a critical determinant in mammary tumorigenesis. These results strongly suggest that there are feedback mechanisms present that can compensate for the expression of a potent oncogene.

HER2/ERBB2 protein is a 185 kDa transmembrane growth factor receptor whose extracellular domain, a 105 kDa fragment (p105), can be released from cell surfaces by proteolytic cleavage. The aim of our study was to compare serum p105 concentrations in normal and pathological pregnancies and to determine whether any correlation exists between preeclampsia and p105 levels. Serum p105 was assayed in 96 non-pregnant women and 89 pregnant women (26 normotensive, 14 normotensive with a history of preeclampsia or fetal hypotrophy, 10 with chronic hypertension, 10 with gestational hypertension and 29 with preeclampsia). Median serum p105 levels (median; 95% confidence interval) were higher in the preeclampsia group (13.9 microg/l; 12.8-16.1 microg/l) than in the normotensive (11.7 microg/l; 10.6-13.3 microg/l; p < 0.05) or non-pregnant groups (9.3 microg/l; 8.9-9.6 microg/l; p < 0.001). There were no significant differences between the other pregnancy groups. In the normotensive group, serum p105 was correlated with the number of gestations (r = 0.46; p < 0.05), parity (r = 0.39; p < 0.05) and placenta weight (r = 0.61; p < 0.05). In preeclamptic women, serum p105 correlated with parity (r = 0.46; p < 0.05). Serum p105 concentrations above 11.9 microg/l were associated with a high odds ratio (OR) for onset of preeclampsia (after adjustment for parity OR = 9.0; 95% CI = 2.3-36.0; p < 0.005). Preeclampsia is associated with increased serum p105 concentrations, which may be related to increased fetomaternal cell traffic.

OBJECTIVE: To assess the rate of HER2/neu overexpression in cytologic specimens by immunocytochemistry (ICC) and compare these results in matched surgical specimens by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH), when available. STUDY DESIGN: ALL cytologic specimens processed for HER2/neu evaluation by ICC (72 cases) and available corresponding histologic specimens (16 cases) were retrieved from our files. ICC was applied to previously Papanicolaou stained, routine fine needle aspirations specimens (64 cases) and cytocentrifuged, alcohol-fixed, fluid specimens (8 cases). FISH was performed on 6 histologic specimens. RESULTS: Overexpression of HER2/neu was seen in 7/22 breast cancers (31.8%), 3/18 pulmonary adenocarcinomas (16.6%), 2/5 colorectal adenocarcinomas (40%), 1/2 adenocarcinomas of the biliary system (50%), 1/3 thyroid papillary carcinomas (33.3%) and 1/3 prostate adenocarcinomas (33.3%). Sixteen cases had IHC in matched histologic specimens: 14 (87.5%) cases were concordant (11 negative and 3 positive in both specimens), 1 case was negative in the cytologic specimen and positive in the histologic specimen (with no amplification by FISH), and 1 case was positive in the cytologic specimen and negative in the histologic specimen (not informative by FISH). CONCLUSION: Our data suggest that overexpression of HER2/neu oncoprotein can be successfully detected in routine cytologic specimens, providing a simple, fast and cost-effective method of selecting patients for specific treatment.

Activating mutations in the ras oncogene are not considered sufficient to induce abnormal cellular proliferation in the absence of cooperating oncogenes. We demonstrate that the conditional expression of an endogenous K-ras(G12D) allele in murine embryonic fibroblasts causes enhanced proliferation and partial transformation in the absence of further genetic abnormalities. Interestingly, K-ras(G12D)-expressing fibroblasts demonstrate attenuation and altered regulation of canonical Ras effector signaling pathways. Widespread expression of endogenous K-ras(G12D) is not tolerated during embryonic development, and directed expression in the lung and GI tract induces preneoplastic epithelial hyperplasias. Our results suggest that endogenous oncogenic ras is sufficient to initiate transformation by stimulating proliferation, while further genetic lesions may be necessary for progression to frank malignancy.

The aim of our study was to determine whether or not the tyrosine kinase receptor, HER2 (also known as ErbB2/Her2/neu), is overexpressed in human osteosarcomas (OS). We studied 15 biopsy and 18 resection specimens at the mRNA and protein levels. HER2 status in the OS specimens was assessed by immunohistochemistry (IHC) and quantitative Real-Time Polymerase chain reaction (PCR). In moderately immunopositive cases fluorescent in situ hybridisation (FISH) analysis was used in order to identify any possible gene amplification. 27 samples were evaluable for IHC and only 1 case showed a moderately positive membrane staining. The remaining samples showed no staining or focal cytoplasmic staining (2 samples). In the moderately positive case, FISH analysis showed no HER-2 gene amplification. There was also no overexpression of HER2 mRNA suggesting this sample was a false-positive immunostain. HER2 mRNA expression was present in ALL samples at a similar level to that in the breast cancer cell line, MCF7, which does not overexpress HER2 and was used as a negative control. In conclusion, this study shows that HER2 mRNA or membranous HER2 protein overexpression is absent in human OS. We noted various inconsistencies in previous published studies, with regard to methodology and the interpretation of the results based on poor methodology. We therefore conclude that the positive data with regard to HER2 overexpression reported in these previous studies is not reliable. Our results suggest that the monoclonal antibody trastuzumab (Herceptin(R)), directed against the HER2-receptor, is not likely to be an effective therapeutic agent in OS.

The activation and phosphorylation of Met, the receptor tyrosine kinase (RTK) for hepatocyte growth factor, initiates the recruitment of multiple signaling proteins, one of which is c-Cbl, a ubiquitin-protein ligase. c-Cbl promotes ubiquitination and enhances the down-modulation of the Met receptor and other RTKs, targeting them for lysosomal sorting and subsequent degradation. The ubiquitination of Met by c-Cbl requires the direct interaction of the c-Cbl tyrosine kinase binding (TKB) domain with tyrosine 1003 in the Met juxtamembrane domain. Although a consensus for c-Cbl TKB domain binding has been established ((D/N)XpYXX(D/E0phi), this motif is not present in Met, suggesting that other c-Cbl TKB domain binding motifs may exist. By alanine-scanning mutagenesis, we have identified a DpYR motif including Tyr(1003) as being important for the direct recruitment of the c-Cbl TKB domain and for ubiquitination of the Met receptor. The substitution of Tyr(1003) with phenylalanine or substitution of either aspartate or arginine residues with alanine impairs c-Cbl-recruitment and ubiquitination of Met and results in the oncogenic activation of the Met receptor. We demonstrate that the TKB domain of Cbl-b, but not Cbl-3, binds to the Met receptor and requires an intact DpYR motif. Modeling studies suggest the presence of a salt bridge between the aspartate and arginine residues that would position pTyr(1003) for binding to the c-Cbl TKB domain. The DpYR motif is conserved in other members of the Met RTK family but is not present in previously identified c-Cbl-binding proteins, identifying DpYR as a new binding motif for c-Cbl and Cbl-b.

PURPOSE: HER-2/neu oncogene is overexpressed in 10-30% of epithelial ovarian cancers and is associated with a poor prognosis. The E1A gene product of adenovirus type 5 down-regulates HER-2/neu and causes tumor regression in animal models. In the current study, we sought to determine the toxicity and biological activity of E1A-lipid complex in ovarian cancer patients. EXPERIMENTAL DESIGN: A Phase I trial involving intraperitoneal (i.p.) administration of E1A-lipid complex was initiated in ovarian cancer patients to assess biological activity (E1A gene transfer/transcription/translation and HER-2/neu expression) and to determine the maximum tolerated dose. Successive cohorts received E1A-lipid complex at doses of 1.8, 3.6, and 7.2 mg DNA/m(2), given as weekly i.p. infusions for 3 of 4 weeks (each cycle) up to a maximum of six cycles. Peritoneal fluid was sampled at baseline and twice monthly for cellularity, cytology, CA-125, and biological activity RESULTS: Fifteen patients, with a median age of 57 years (range, 43-81) were recruited. Three (1.8 mg DNA/m(2)), 4 (3.6 mg DNA/m(2)), and 8 patients (7.2 mg DNA/m(2)) received i.p. E1A. A total of 91 infusions (range, 1-18) was administered. Abdominal pain was the dose-limiting toxicity, and the maximum-tolerated dose was 3.6 mg DNA/m(2). E1A gene transfer and expression was observed in ALL of the patients and at ALL of the dose levels. HER-2/neu down-regulation could be demonstrated in the tumor cells of 2 patients (18%). There was no correlation between dose and biological activity. CONCLUSIONS: I.P. EIA-lipid complex gene therapy is feasible and safe. Future studies, either alone or in combination with chemotherapy, particularly in patients with minimal residual disease, should be evaluated.

The status of the erbB-2 (human epidermal growth factor receptor 2/neu) proto-oncogene in canine osteosarcoma (OSA) has not been reported previously. In this study we used real-time reverse transcriptase polymerase chain reaction to evaluate erbB-2 expression in seven canine OSA cell lines and 10 canine OSA tissue samples. We determined erbB-2 to be significantly overexpressed in 86% (six of seven) of the cell lines and 40% (4 of 10) of the OSA tissues samples. Given the importance of erbB-2 in human breast cancer, the finding of erbB-2 overexpression in canine OSA may be important in further understanding the pathogenesis and possible therapies of OSA.

BACKGROUND: To evaluate longitudinal variations of serum HER-2/neu extracellular domain (sHER-2) in metastatic breast cancer patients receiving combined trastuzumab treatment. PATIENTS AND METHODS: Thirty-three patients were monitored by serial sHER-2 ELISA (Oncogene Science). Results were compared to time to progression (TTP) and survival from treatment initiation. Non parametric statistical tests were used. RESULTS: Median sHER-2 before first injection was 41.37 ng/ml (range 7.54-1597.00 ng/ml, n=32). Mean sHER-2 levels differed significantly between responders (n=20) and non responders (n=13) (p<0.0001). Median TTP (266 days, range 35-1000 days) was unrelated to clinico-biological variables at diagnosis or number and site of metastases before treatment. Patients with pre-treatment sHER-2 levels < or = 30 ng/ml (n=14) had a significantly longer TTP than the group with sHER-2 > 30 ng/ml (n=18) (p=0.0346) and sHER-2 levels were of prognostic value for overall survival from first injection (p=0.0150). CONCLUSION: Our results show that monitoring serum HER-2/neu levels during metastatic breast cancer can provide a real time assessment of a woman s HER-2/neu status and can provide important information for therapeutic decisions.

CONTEXT: tumor marker assays, especially those used to indicate the right therapy, should be standardized. OBJECTIVE: To analyze the current methods for the HER-2/neu (h2n) oncogene status by immunohistochemical (IHC) analysis, fluorescence in situ hybridization (FISH), and chromogenic in situ hybridization (CISH) and compare those results with the chromosome 17 copy number and the status of the topoisomerase II alpha (TPIIalpha) gene. DESIGN: We tested 50 infiltrating ductal breast carcinomas (pTNM status varied from pT1 N0 to pT4 N1) using the Food and Drug Administration (FDA)-approved methods HercepTest and pathway for overexpression of h2n. We also used FISH and CISH to test for h2n amplification and CISH to test for chromosome 17 (c17) and TPIIalpha. The p53 and Ki-67 factors were also evaluated by IHC analysis. RESULTS: h2n overexpression (3+) and amplification were observed in only 6 (12%) of 50 cases by IHC analysis, FISH, and CISH. Three cases that initially scored 3+ and 2+ had 4 to 5.95 signals (equivocal) by FISH but when corrected by the h2n/c17 ratio were nonamplified. TPIIalpha isomerase was amplified in only 2 (4%) of the 50 cases. Nineteen (38%) of the 50 cases were aneuploidic. ALL h2n amplified cases had high proliferative activity, but only 2 of 6 had p53 protein alterations. CONCLUSIONS: The HercepTest and pathway IHC assay h2n were fully concordant for the 3+ cases. The 3+ cases had to be confirmed in 75% of the tumor area examined. These 2 IHC assays were fully concordant with FISH and CISH. The 2 in situ hybridization (ISH) assays were 94% concordant for the 50 cases. The cutoff signal points for both ISH assays should be 6 or more. Thus, there is no need for the c17 ratio correction. tumor heterogeneity appears not be a major problem, but our percentage of amplified cases is lower than previously reported. The FDA-approved IHC and ISH assays should give relatively uniform results when used following our recommendations.

A retrospective immunohistological assay identified estrogen (ER) (72%) and progesterone (PR) (71%) receptor content in tumors from 76 patients with endometroid cancer (ER+ PR(+)--63.2%; ER- PR(-)--22.3%; ER+ PR- 9.2%; ER- PR+ -5.3%). Pattern R+ involved well differentiated cells, slight invasion of the myometrium and infrequent spreading to the regional lymph nodes, as compared with cases of unidentified ER or PR. Five-year survival in patients with ER+ PR+ tumors was 83% vs. 53% in cases without steroid hormone receptor expression (p = 0.04). HER 2 overexpression was found in 31.6% of tumors involving a decrease in total survival from 73 to 54.2% (p = 0.04). No significant correlation was established between ER and PR, on the one hand, and HER 2 expression, on the other. HER 2 overexpression leveled off the prognostic value of steroid receptor expression to a considerable degree; relapse incidence in patients with HER 2 overexpression in ER+ PR+ tumors rose 9-26.7% while five-year survival dropped 88-60% (p = 0.03). A distinct correlation between ER and PR expression (r = 0.96) was reported by D.C. Alfred et al. and verified by the H-scor procedure (R.A. Mc Clelland et al.). This procedure for steroid receptor expression determination is as the first unsophisticated, yet informative, method.

Determining of HER-2/neu oncogene amplification has become clinically important for managing breast cancer. Fluorescent in situ hybridization (FISH) and immunohistochemistry (IHC) are currently regarded as the standard methods. Chromogenic in situ hybridization (CISH) was investigated as a new modification with an accurate, sensitive technique. From 1998 to 2002, using CISH and IHC, the amplification and protein expression of the HER-2/neu oncogene were examined using paraffin sections in 130 breast carcinomas and to determine the prognostic role of HER-2/neu for outcome after a follow-up of 24- 64 months. Amplifications by CISH and overexpression by IHC were observed in 28 (22%) and 27 cases (20.8%), respectively. Of the 104 patients, 20 patients (19.2%) with amplification had a shorter disease-free interval (34.9 months vs. 38.0 months in controls) (p=0.372). 15 patients (14.4%) had a disease recurrence, but there is no significant difference between 3 patients amplifying the oncogene and 12 patients without oncogene (20.6 months vs. 19.6 months) (p=0.862). 6 patients (5.8%) of these died. CISH is a useful alternative, particularly for confirming the IHC results. There is no relationship between the early recurrence and the HER-2/neu positive group, but lymph node status was statistically significant.

Immunizations with the oncogenic protein Her-2/neu elicit Abs exerting diverse biological effects--depending on epitope specificity, tumor growth may be inhibited or enhanced. Trastuzumab (herceptin) is a growth-inhibitory humanized monoclonal anti-Her-2/neu Ab, currently used for passive immunotherapy in the treatment of breast cancer. However, Ab therapies are expensive and have to be repeatedly administered for long periods of time. In contrast, active immunizations produce ongoing immune responses. Therefore, the study aims to generate peptide mimics of the epitope recognized by trastuzumab for vaccine formulation, ensuring the subsequent induction of tumor growth inhibitory Abs. We used the phage display technique to generate epitope mimics, mimotopes, complementing the screening Ab trastuzumab. Five candidate mimotopes were isolated from a constrained 10 mer library. These peptides were specifically recognized by trastuzumab, and showed distinctive mimicry with Her-2/neu in two experimental setups. Subsequently, immunogenicity of a selected mimotope was examined in BALB/c mice. Immunizations with a synthetic mimotope conjugated to tetanus toxoid resulted in Abs recognizing Her-2/neu in a blotted cell lysate as well as on the SK-BR-3 cell surface. Analogous to trastuzumab, the induced Abs caused internalization of the receptor from the cell surface to endosomal vesicles. These results indicate that the selected mimotopes are suitable for formulation of a breast cancer vaccine because the resulting Abs show similar biological features as trastuzumab.

Breast cancer tissues from 271 cases were analyzed immunologically for c-erbB-2 oncoprotein (HER-2/neu), epidermal growth factor receptor (EGF-R) and estrogen receptor (ER). Overexpression of both c-erbB-2 oncoprotein and EGF-R showed an inverse association with ER and a direct association with metastatic involvement of lymph node and high histological grade. The frequency of c-erbB-2 and EGF-R overexpression was significantly higher among postmenopausal cases in comparison with premenopausal cases. Further, only in postmenopausal patients, c-erbB-2 oncoprotein (chi2 = 6.4, P < 0.05) and EGF-R (chi2 = 6.4, p < 0.05) as well as their concomitant expression (chi2 = 11.5, p < 0.01) revealed a statistically significant association with ER.

Fatty acid synthase (FAS) activity is a potential therapeutic target to treat cancer and obesity. Here, we have identified a molecular link between FAS and HER2 (erbB-2) oncogene, a marker for poor prognosis that is overexpressed in 30% of breast and ovarian cancers. Pharmacological FAS inhibitors cerulenin and C75 were found to suppress p185(HER2) oncoprotein expression and tyrosine-kinase activity in breast and ovarian HER2 overexpressors. Similarly, p185(HER2) expression was dramatically down-regulated when FAS gene expression was silenced by using the highly sequence-specific mechanism of RNA interference (RNAi). Pharmacological and RNAi-mediated silencing of FAS specifically down-regulated HER2 mRNA and, concomitantly, caused a prominent up-regulation of PEA3, a transcriptional repressor of HER2. A cytoplasmic redistribution of p185(HER2) was associated with marked morphological changes of FAS RNAi-transfected cells, whereas chemical inhibitors of FAS promoted a striking nuclear accumulation of p185(HER2). The simultaneous targeting of FAS and HER2 by chemical FAS inhibitors and the humanized antibody directed against p185(HER2) trastuzumab, respectively, was synergistically cytotoxic toward HER2 overexpressors. Similarly, concurrent RNAi-mediated silencing of FAS and HER2 genes synergistically stimulated apoptotic cell death in HER2 overexpressors. p185(HER2) was synergistically down-regulated after simultaneous inhibition of FAS and HER2 by either pharmacological inhibitors or small interfering RNA. These findings provide evidence of an active role of FAS in cancer evolution by specifically regulating oncogenic proteins closely related to malignant transformation, strongly suggesting that HER2 oncogene may act as the key molecular sensor of energy imbalance after the perturbation of tumor-associated FAS hyperactivity in cancer cells.

The HER2/neu oncoprotein is a major target for the development of new cancer therapies and is similar to the estrogen receptor, which guides hormone therapy. The HER2/neu status is used to guide therapy decisions in patients with HER2/neu-overexpressing breast cancer tumors. The HER2/neu oncogene, or c-erbB-2, encodes a transmembrane receptor protein that is expressed on normal epithelial cells and can be overexpressed in breast cancer cells. Studies have shown that the extracellular domain (ECD) of the HER2/neu oncoprotein is released from the cell and can be measured in the circulation of women with breast cancer. Enzyme-linked immunosorbent assay methods used to measure the circulating HER2/neu ECD have shown that the prevalence of elevated ECD levels is approximately 18.1% in women with primary breast cancer and approximately 45.6% in women with metastatic breast cancer (MBC). Many studies have monitored the circulating ECD levels after surgery and indicate that increasing ECD levels can indicate recurrence of breast cancer earlier than clinical diagnosis. Studies in women with MBC showed that serial changes in circulating HER2/neu ECD levels paralleled the clinical course of disease, regardless of the treatment regimen. Several studies identified a subgroup of patients with MBC who had HER2/neu-negative disease by tissue testing but developed elevated ECD levels with MBC. In contrast to tissue testing, which is a one-time event, monitoring the circulating levels of the HER2/neu ECD in patients with breast cancer provides a real-time assessment of the HER2/neu status and provides important information for managing the therapy of patients with MBC.

It has been suggested that urokinase plasminogen activator (uPA) in cancer cells is upregulated by the p185 kD form of the HER-2/neu oncogene. This study was performed to see if the extracellular domain of HER-2/neu, the p105 fraction, which is found in the circulation, has any regulatory influence on uPA in patients with cervical cancer. Levels of uPA and p105 HER-2/neu were determined in blood from age-matched controls and patients with early and advanced cervical cancer. In the patients with cervical cancer, samples were obtained before treatment only. No significant increase in either uPA or HER-2/neu was seen in the patients before their treatment for cervical cancer. Additionally, correlation analysis of circulating uPA and HER-2/neu against each other in both the controls and cervical cancer indicated no relationship except in early stage disease. It appears that circulating uPA and HER-2/neu are not altered in patients with cervical cancer, either early or advanced stages. The upregulation of uPA by HER-2/neu seen in cancer cells in vitro appears to occur in vivo in early stage cervical cancer.

PURPOSE: Chromogenic in situ hybridization (CISH) is a new modification of the fluorescence in situ hybridization (FISH) technique for detection of oncogene amplification in archival tumor samples. In CISH, the oncogene probe is detected using a peroxidase reaction, allowing use of transmitted light microscopy. We compared detection of HER-2/neu amplification by CISH with a Food and Drug Administration-approved two-color FISH test in an interlaboratory setting. EXPERIMENTAL DESIGN: Formalin-fixed paraffin-embedded tumor samples from 197 breast cancers were analyzed for HER-2 amplification by CISH. Two-color FISH (PathVysion) CISH of 17 centromere was done if the observer considered it necessary to ascertain amplification status in tumors with borderline HER-2 CISH copy numbers. RESULTS: Paired CISH/FISH results were available from 192 (97%) of 197 cases, no clear difference in success rates of either method was observed. Centromere 17 CISH was considered necessary in seven tumors. CISH and two-color FISH results were concordant in 180 cases (93.8%). There were 92 and 88 tumors found HER-2 amplified and nonamplified, respectively, by both methods. Eight tumors were amplified by CISH but not by FISH, and four tumors exhibited the opposite condition (kappa coefficient 0.875). In 7 of 12 cases differences between the two methods could have related to a lack of CISH chromosome 17 information. The remaining cases were explained by difficult histology (ductal carcinoma in situ, poor representativity, dense lymphocytic infiltration, or intratumoral heterogeneity). CONCLUSIONS: These results indicate that CISH could provide an accurate and practical alternative to FISH for clinical diagnosis of HER-2/neu oncogene amplification in archival formalin-fixed breast cancer samples.

We evaluated p186Her2 overexpression and HER2 oncogene amplification in recurrent vulvar Paget s disease. We identified six patients with recurrent vulvar Paget s disease in our archives. The number of recurrences ranged from 1 to 11 over a time period of 1-168 months. Recurrences were evaluated immunohistochemically for p185Her2 overexpression with the HercepTest and for HER2 oncogene amplification with fluorescence in situ hybridization. p185Her2 overexpression was scored as 3 in two patients, as 2 in two patients, and as 1 in two patients. ALL patients with scores 2 and 3 showed HER2 oncogene amplification. Overexpression of p185Her2 and HER2 oncogene amplification appears to be common in recurrent vulvar Paget s disease.

HER2/neu, a receptor tyrosine kinase oncogene, promotes mitogenic growth and antiapoptotic activity in cancer cells. Strong expression of HER2/neu in cancers has been associated with poor prognosis. Alternative reading frame protein (ARF), a tumor suppressor protein encoded by a gene located in the Ink4a/ARF gene locus, is frequently inactivated in human cancers. Little is known about the tumor suppressor role of ARF in HER2/neu-overexpressing cancers. Here, we applied the ARF gene as a tumor-suppressive agent for HER2/neu-overexpressing cells under the control of a tetracycline (tet)-regulated gene expression system. We found that ARF antagonized protein kinase B (PKB)/Akt-mediated p27Kip1 phosphorylation and increased p27 stability in HER2/neu-overexpressing cells. ARF expression also led to decreased levels of Cul1 and Skp2, two proteins involved in p27 degradation. We also found that ARF caused apoptosis in HER2/neu-overexpressing cells, and sensitized cells to apoptosis induced by the chemotherapeutic agents taxol and 2-methoxyestradiol. Most significantly for clinical application, we found that ARF inhibited HER2/neu-mediated cell growth, transformation, and tumorigenesis. These findings indicate that modulation of ARF activity may be a useful therapeutic intervention in HER2-overexpressing cancers.

We designed our experiments to evaluate whether fatty acid synthase (FAS), a lipogenic enzyme linked to tumor virulence in population studies of human cancer, is necessary for the malignant transformation induced by Her-2/neu (erbB-2) oncogene, which is overexpressed not only in invasive breast cancer but also in premalignant atypical duct proliferations and in ductal carcinoma in situ of the breast. To avoid the genetic complexities associated with established breast cancer cell lines, we employed NIH-3T3 mouse fibroblasts engineered to overexpress human Her-2/neu coding sequence. NIH-3T3/Her-2 cells demonstrated a significant upregulation of FAS protein expression, which was dependent on the upstream activation of mitogen-activated protein kinase and phosphatidylinositol 3 -kinase/AKT pathways. Remarkably, pharmacological FAS blockade using the mycotoxin cerulenin or the novel small compound C75 completely suppressed the state of Her-2/neu-induced malignant transformation by inhibiting the ability of NIH-3T3/Her-2 cells to grow under either anchorage-independent (i.e., to form colonies in soft agar) or low-serum monolayer conditions. Moreover, NIH-3T3/Her-2 fibroblasts were up to three times more sensitive to chemical FAS inhibitors relative to untransformed controls as determined by MTT-based cell viability assays. In addition, pharmacological FAS blockade preferentially induced apoptotic cell death of NIH-3T3/Her-2 fibroblasts, as determined by an ELISA for histone-associated DNA fragments and by the terminal deoxynucleotidyltransferase (TdT)-mediated nick end labeling assay (TUNEL). Interestingly, the degree of Her-2/neu oncogene expression in a panel of breast cancer cell lines was predictive of sensitivity to chemical FAS inhibitors-induced cytotoxicity, while low-FAS expressing and chemical FAS inhibitors-resistant MDA-MB-231 breast cancer cells became hypersensitive to FAS blockade when they were engineered to overexpress Her-2/neu. Our observations strongly suggest that inhibition of FAS activity may provide a new molecular avenue for chemotherapeutic prevention and/or treatment of Her-2/neu-related breast carcinomas.

OBJECTIVES: Amplification of the proto-oncogene c-erbB-2 (HER-2/neu) has been shown to be a prognostic marker in many kinds of cancer including oral squamous cell carcinoma (OSCC). In order to obtain further information on the c-erbB-2 gene product p185, it is necessary to quantify expression levels. In this study we used an enzyme-linked immunosorbent assay (ELISA) for the extracellular domain of p185 to determine whether a soluble oncoprotein fragment can be detected in the serum of OSCC patients. METHOD: Sera from 84 OSCC patients, 51 breast cancer patients (as positive controls), and 15 healthy controls were assayed in an ELISA. To study c-erbB-2 overexpression in OSCC, and breast cancer tissue samples we used an immunohistochemical technique. RESULTS: The mean serum value (ng/ml, mean/SD) for the normal controls was 8.46/1.29. We chose the 95% level of normal controls as a cut-off to distinguish individuals with elevated levels. The breast cancer patients and OSCC patients serum values were 13.83/6.82 and 13.1/4.56, respectively. Significant differences (P < 0.0001) were observed between normal control and OSCC, normal control and the breast cancer group. Immunohistochemically detectable p185 (intermediate to high) was noted in 30 of 61 OSCC, and 24 of 51 breast cancer patients. There was a trend of association of serum oncoprotein fragment levels with tumor stages, but not with tumor sizes, nodal stages, metastases, and oral habits including betel quid chewing, alcohol drinking and smoking in the OSCC group. CONCLUSION: The results of the present study raise the possibility that soluble c-erbB-2 protein levels in serum is a useful parameter for monitoring the disease status as well as the effect of therapy on patients with OSCC.

OBJECTIVE: To detect serum HER-2 oncoprotein levels in patients with operable and metastatic breast cancers, and to study the correlations between serum HER-2 level and lymph node status as well as other clinical parameters. METHODS: A total of 120 women were studied consisting of 10 healthy volunteers, 31 benign breast disease, 53 operable breast cancer, and 26 metastatic breast cancer patients. The levels of serum HER-2 were measured using an enzyme-liked immunosorbent assay (ELISA). RESULTS: The mean serum HER-2 levels were 9.6 +/- 1.5 ng/mL in healthy volunteers, 11.9 +/- 1.6 ng/mL in benign breast disease, 13.2 +/- 4.2 ng/mL in operable breast cancer, and 30.5 +/- 30.8 ng/mL in metastatic breast cancer patients. The former is much lower than the latter three (P = 0.02, 0.001, 0.03, respectively). If using 15 ng/mL as a normal baseline, elevated serum HER-2 levels were observed in none of the healthy volunteers as well as patients with benign disease, but in 18.9% (10/53) operable breast cancer patients and 61.5% (16/26) metastatic patients. In patients with operable breast cancer, there was a positive correlation between serum concentrations of HER-2 and the size of primary tumor (P < 0.05), whereas there was no correlation between serum concentration and axillary lymph node or estrogen receptor status. In patients with metastatic disease, there was no correlation with site of metastases (P > 0.05). CONCLUSION: Serum HER-2 level was strongly correlated with tumor loads and clinical stages, thus acting as a promising predictor of cancer recurrence in breast cancer patients.

OBJECTIVE: To investigate the expression of the proto-oncogene eIF4E in laryngeal squamous cell carcinoma and its relationship with clinical pathology. METHOD: Sections of 37 samples of laryngeal squamous cell carcinoma (LSCC) and 10 samples of vocal cords polyp were analyzed with anti-eIF4E polyclonal antibody utilizing SP (Streptavidin Peroxidase) immunohistochemical technique. RESULT: ALL 37 LSCC samples overexpressed eIF4E in the tumors (eIF4E score: 30 approximately 210), whereas no staining was observed in 10 samples of vocal cords polyp (eIF4E score: 0). There was a significant correlation between overexpression of protein eIF4E with T stage, N stage, histological grade, recurrence and the states of metastases (P < 0.01). It did not correlate with age, sex, and site of tumor (P > 0.05). CONCLUSION: The eIF4E plays an important role on tumorgenesis, development, invasion and metastases of laryngeal squamous cell carcinoma. There was a correlation between the overexpression of protein eIF4E with TNM stage, histological grade, recurrence and metastases. eIF4E in the laryngeal squamous cell carcinoma can be considered as an independent prognostic factor and tumour molecular marker.

Histological differentiation between chronic pancreatitis and pancreatic cancer, especially in biopsy material, remains challenging and the frequent association of secondary chronic pancreatitis (due to ductal obstruction) with pancreatic cancer causes additional diagnostic problems. Our study, using anti-ErbB2 antibodies from Santa Cruz and Dako in tissues from the normal pancreas, chronic pancreatitis and pancreatic cancer showed that these antibodies discriminate between primary chronic pancreatitis and secondary chronic pancreatitis due to pancreatic cancer. Tissues from 28 pancreatic cancer patients, 15 chronic pancreatitis patients and 12 organ donors or early autopsy cases were subjected to immunohistochemical studies using polyclonal ErbB2 antibodies from Santa Cruz and Dako. The Santa Cruz antibody immunoreacted with islet cells in ALL tissues from the normal pancreas and pancreatic cancer but not in any chronic pancreatitis specimen. The Dako antibody showed a membrane staining of ductal and ductular cells only in chronic pancreatitis cases but in none of the normal or cancer specimens. Moreover, in chronic pancreatitis cases, ductular cells were stained with the Santa Cruz antibody only in the severe form, but not in the mild or moderate form of the disease. The utilized ErbB2 antibodies discriminate between the normal pancreas, chronic pancreatitis and pancreatic cancer. Hence, these antibodies seem to present an additional useful aid in the surgical pathology of pancreatic diseases.

OBJECTIVE: The purpose of this study was to investigate the expression of epidermal growth factor receptor and c-erbB-2 oncoprotein in trophoblast populations of placenta accreta. STUDY DESIGN: Paraffin sections of 43 placental specimens with (cases) and 43 without (controls) placenta accreta were studied immunohistochemically for epidermal growth factor receptor and c-erbB-2 expression in the syncytiotrophoblast, villous cytotrophoblast, and extravillous cytotrophoblast. Epidermal growth factor receptor and c-erbB-2 protein levels were also performed by Western blot analysis. Controls were matched for gestational age in this case-control study. RESULTS: The percentage of strong/intermediate immunoreactivity of epidermal growth factor receptor in the syncytiotrophoblast was significantly higher in cases (98%) than controls (79%; odds ratio,11.1; 95% CI, 1.3-92.0; P = .03), although strong/intermediate immunoreactivity of c-erbB-2 in the syncytiotrophoblast was significantly lower in cases (35%) than controls (81%; odds ratio, 0.1; 95% CI, 0.1-0.3; P < .001). Epidermal growth factor receptor and c-erbB-2 expression in the villous and extravillous cytotrophoblastic cells were not significantly different between controls and cases ( P > .05). Most immunoreactive bands on Western blots were consistent with the trends of immunohistochemical findings. CONCLUSION: The development of placenta accreta is related closely to the differential expression of epidermal growth factor receptor and c-erbB-2 in the syncytiotrophoblast.

PURPOSE: To evaluate EGFR and HER2 copy number changes and to assess their significance to tumor progression in a large group of patients with larynx cancer through the construction of a tissue microarray (TMA) consisting of 1,385 biopsies. METHODS: Fluorescent in situ hybridization (FISH) was applied to analyze the tumors. FISH was successful for EGFR in 1,080 (77.98%) and for HER2 in 683 (49.31%). RESULTS: HER2 was amplified in 1.02% of cases. Amplification did not correlate with the tumor phenotype-clinical stage, and grade. The low frequency of amplification of HER2 oncogene in larynx tumors showed that the mechanism responsible for the high level of receptor overexpression still remains unclear in the majority of cases. Amplification of EGFR was found in 10.37% of cases. The analysis revealed a lack of correlation between amplification of the oncogenes and the tumor phenotype. We observed a lack of difference between the samples of primary tumors and advanced disease carcinomas--tumors with regional/distant metastases and recurrent tumors regarding oncogene amplification. CONCLUSION: These results suggest that EGFR amplification is a relatively rare event in larynx carcinogenesis that obviously does not predispose to tumor progression.

Overexpression and activation of HER-2/neu (also known as c-erbB-2), a proto-oncogene, was found in about 30% of human breast cancers, promoting cancer growth and making cancer cells resistant to chemo- and radio-therapy. Wild-type p53 is crucial in regulating cell growth and apoptosis and is found to be mutated or deleted in 60-70% of human cancers. And some cancers with a wild-type p53 do not have normal p53 function, suggesting that it is implicated in a complex process regulated by many factors. In the present study, we showed that the overexpression of HER-2/neu could decrease the amount of wild-type p53 protein via activating PI3K pathway, as well as inducing MDM2 nuclear translocation in MCF7 human breast cancer cells. Blockage of PI3K pathway with its specific inhibitor LY294002 caused G1-S phase arrest, decreased cell growth rate and increased chemo- and radio-therapeutic sensitivity in MCF7 cells expressing wild-type p53. However, it did not increase the sensitivity to adriamycin in MDA-MB-453 breast cancer cells containing mutant p53. Our study indicates that blocking PI3K pathway activation mediated by HER-2/neu overexpression may be useful in the treatment of breast tumors with HER-2/neu overexpression and wild-type p53.

PURPOSE: The role of HER-2/neu in the response of esophageal cancer to radiation is not well known. The purpose of this study was to evaluate the effect of an anti-HER-2/neu antibody trastuzumab on the proliferation, cell cycle distribution, and radiosensitivity of esophageal cancer cell lines. EXPERIMENTAL DESIGN: expression of HER-2/neu protein by four esophageal squamous cancer cell lines (KE4, TE8, TE9, and TE10) and an esophageal adenocarcinoma cell line (SKGT4) was assessed using immunohistochemical (IHC) analysis and flow cytometry. We also evaluated HER-2/neu oncogene expression by fluorescence in situ hybridization. As a control for HER-2/neu protein expression and gene amplification, breast cancer cell lines (MCF7, MDA MB175VII, and SKBR3) were also examined. The cytotoxity of trastuzumab (0.1-200 microg/mL) was estimated by the MTT assay, and the cell cycle distribution was determined by flow cytometry. The effect of 10 microg/mL trastuzumab combined with radiation was assessed by a clonogenic assay. RESULTS: Flow cytometry and IHC revealed that two esophageal cancer cell lines (TE9 and SKGT4) showed HER-2/neu expression (IHC 1+ and mean fluorescence intensity of 11-20), while the other esophageal cancer cell lines were negative for HER-2/neu expression. Although trastuzumab alone had no effect on the esophageal cancer cell lines, the combination of 10 microg/mL trastuzumab with radiation showed a synergistic effect on the HER-2/neu expressing cell lines. CONCLUSIONS: This study suggested that trastuzumab plus irradiation may be effective for the treatment of esophageal cancers, including adenocarcinoma and squamous cell cancer with HER-2/neu expression.

BACKGROUND: The relationship between the intake of olive oil, the richest dietary source of the monounsaturated fatty acid oleic acid (OA; 18:1n-9), and breast cancer risk and progression has become a controversial issue. Moreover, it has been suggested that the protective effects of olive oil against breast cancer may be due to some other components of the oil rather than to a direct effect of OA. METHODS: Using flow cytometry, western blotting, immunofluorescence microscopy, metabolic status (MTT), soft-agar colony formation, enzymatic in situ labeling of apoptosis-induced DNA double-strand breaks (TUNEL assay analyses), and caspase-3-dependent poly-ADP ribose polymerase (PARP) cleavage assays, we characterized the effects of exogenous supplementation with OA on the expression of Her-2/neu oncogene, which plays an active role in breast cancer etiology and progression. In addition, we investigated the effects of OA on the efficacy of trastuzumab (Herceptin), a humanized monoclonal antibody binding with high affinity to the ectodomain of the Her-2/neu-coded p185(Her-2/neu) oncoprotein. To study these issues we used BT-474 and SKBr-3 breast cancer cells, which naturally exhibit amplification of the Her-2/neu oncogene. RESULTS: Flow cytometric analyses demonstrated a dramatic (up to 46%) reduction of cell surface-associated p185(Her-2/neu) following treatment of the Her-2/neu-overexpressors BT-474 and SK-Br3 with OA. Indeed, this effect was comparable to that found following exposure to optimal concentrations of trastuzumab (up to 48% reduction with 20 microg/ml trastuzumab). Remarkably, the concurrent exposure to OA and suboptimal concentrations of trastuzumab (5 microg/ml) synergistically down-regulated Her-2/neu expression, as determined by flow cytometry (up to 70% reduction), immunoblotting, and immunofluorescence microscopy studies. The nature of the cytotoxic interaction between OA and trastuzumab revealed a strong synergism, as assessed by MTT-based cell viability and anchorage-independent soft-agar colony formation assays. Moreover, OA co-exposure synergistically enhanced trastuzumab efficacy towards Her-2/neu overexpressors by promoting DNA fragmentation associated with apoptotic cell death, as confirmed by TUNEL and caspase-3-dependent PARP cleavage. In addition, treatment with OA and trastuzumab dramatically increased both the expression and the nuclear accumulation of p27(Kip1), a cyclin-dependent kinase inhibitor playing a key role in the onset and progression of Her-2/neu-related breast cancer. Finally, OA co-exposure significantly enhanced the ability of trastuzumab to inhibit signaling pathways downstream of Her-2/neu, including phosphoproteins such as AKT and MAPK. CONCLUSIONS: These findings demonstrate that OA, the main monounsaturated fatty acid of olive oil, suppresses Her-2/neu overexpression, which, in turn, interacts synergistically with anti-Her-2/neu immunotherapy by promoting apoptotic cell death of breast cancer cells with Her-2/neu oncogene amplification. This previously unrecognized property of OA offers a novel molecular mechanism by which individual fatty acids may regulate the malignant behavior of breast cancer cells and therefore be helpful in the design of future epidemiological studies and, eventually, dietary counseling.

BACKGROUND: The protein encoded by the c-erbB-2 gene is a membrane receptor expressed in a variety of solid human cancers and directly related to poor prognosis. The objective of this work was to evaluate the clinical value of the quantification of membranous oncoprotein levels in gastric cancer. MATERIALS AND METHODS: Membranous c-erbB-2 levels were examined by means of a sandwich immunoenzymatic assay in 82 patients with gastric cancer. The median follow-up period for these patients was 16 months. In addition, c-erbB-2 expression was analyzed by immunohistochemistry in 57 gastric carcinomas. RESULTS: Membranous c-erbB-2 levels ranged widely in the studied tumors (44-112,000 NHU/mg protein). Median c-erbB2 content was significantly higher in intestinal-type tumors than in diffuse-type tumors (p = 0.01). In addition, high levels of c-erbB-2 were significantly associated with shorter relapse-free survival and overall survival in patients with resectable gastric carcinomas (p = 0.01 and p = 0.04, respectively). However, the correlation between immunohistochemistry and ELISA determinations did not reach statistical significance. CONCLUSION: Our results suggest a potential prognostic value of membranous c-erbB-2 quantification by immunoenzymatic assay in gastric cancer. However, its possible role in the selection of patients with a view to the possible introduction of Herceptin as a novel drug against gastric cancer is at present uncertain.

The critical Val/Glu mutation in the membrane spanning domain of the rat Neu receptor confers the ability for ligand-independent signaling and leads to increased dimerization and transforming ability. There is evidence that the two transmembrane interacting helices play a role in receptor activation by imposing orientation constraints to the intracellular tyrosine kinase domains. By using MD simulations we have attempted to discriminate between correct and improper helix-helix packing by examining the structural and energetic properties of preformed left-handed and right-handed structures in a fully hydrated DMPC bilayer. The best energetic balance between the residues at the helix-helix interface and the residues exposed to the lipids is obtained for helices in symmetrical left-handed interactions packed together via Glu side chain/Ala backbone interhelical hydrogen bonds. Analyses demonstrate the importance of the ATVEG motif in helix-helix packing and point to additional contacting residues necessary for association. Our findings, ALL consistent with experimental data, suggest that a symmetrical left-handed structure of the helices could be the transmembrane domain configuration that promotes receptor activation and transformation. The present study may provide further insight into signal transduction mechanisms of the ErbB/Neu receptors.

High levels of the Wilms tumor 1 (WT1) protein and mRNA had been associated with aggressive phenotypes of breast tumors. Here we report that the HER2/neu oncogene increases WT1 expression. Approximately threefold higher levels of WT1 protein were observed in MCF-7 breast cancer cells transfected with the HER2/neu oncogene than in parental MCF-7 cells. Conversely, inhibition of HER2/neu with the anti-HER2/neu trastuzumab (Herceptintrade mark) antibody decreased WT1 protein levels in HER2/neu-overexpressing BT-474 and SKBr3 cells. We also found that HER2/neu engages Akt to regulate WT1 levels since inhibition of Akt reduced WT1 levels. Decreased expression of WT1 protein led to cell cycle arrest at the G1 phase and increased apoptosis in HER2/neu-overexpressing cells, which is correlated with decreased cyclin D1 and Bcl-2 levels. Our data indicate that HER2/neu engages Akt to increase WT1 expression, and that WT1 protein plays a vital role in regulating cell cycle progression and apoptosis in HER2/neu-overexpressing breast cancer cells.

I-2PP2A/SET, the translocation breakpoint-encoded protein expressed in acute undifferentiated leukemia, was identified as an inhibitor of protein phosphatase 2A (PP2A). Induction of exogenous I-2PP2A/SET at a ratio of 1:1 to the endogenous protein resulted in suppression of cell proliferation. In contrast, siRNA-mediated depletion of I-2PP2A/SET resulted in enhanced cell proliferation. Depletion of I-2PP2A/SET was accompanied with a decrease in the number of cells in G1 and an increase in cells in S phase. To examine the mode of action by which I-2PP2A/SET suppresses cell proliferation, we determined the effect of over-expressed I-2PP2A/SET on ERK activation. I-2PP2A/SET suppressed activation of ERK following EGF stimulation but did not affect activation levels of stress kinases, JNK and p38. By contrast, knocking down I-2PP2A/SET by siRNA resulted in enhancement of ERK and MEK activations, suggesting that I-2PP2A/SET negatively regulates MEK/ERK. These data suggest that I-2PP2A/SET negatively regulates cell growth by inhibiting the G1/S transition and inhibiting the MEK/ERK pathway stimulated by external stimuli. These data demonstrate that I-2PP2A/SET potentially functions as a tumor suppressor.

OBJECTIVES: Our aim is to determine the expression of the cerbB-2 oncoprotein in prostate cancers using an immunohistochemistry staining and to compare these results with several clinical and histological prognostic factors. METHODS: An immunohistochemical staining using the cerbB-2 monoclonal antibody (Dako) was performed in 32 radical prostatectomy specimens diagnosed of adenocarcinoma. The intensity of cerbB-2 expression was evaluated with a scale that variated from 0 (no staining) to 3+ (strong complete membrane staining) according to published guidelines. Association of cerbB-2 index immunoreactivity with clinical and histological prognostic factors was examined. RESULTS: Definite positive membranous staining was detected in 14 of 32 neoplastic cases (44%). Such overexpression was correlated with higher Gleason grade (p=0.04) and higher stage of disease (p=0.038). CONCLUSIONS: 1) This study shows that 44% of ALL prostate cancer express the cerbB-2 oncoprotein with immunohistochemical technique. 2) These findings suggest that is necessary to standardize the immunohistochemical staining procedure with cerbB-2 in prostate adenocarcinoma. 3) The level of cerbB-2 expression was correlated with Gleason grade and clinical stage.

Antigene oligonucleotides have the potential to regulate gene expression through site-specific DNA binding. However, in vivo applications have been hindered by inefficient cellular uptake, degradation, and strand displacement. Peptide nucleic acids (PNAs) address several of these problems, as they are resistant to degradation and bind DNA with high affinity. We designed two cationic pyrimidine bis-PNAs (cpy-PNAs) to target the polypurine tract of the HER-2/neu promoter and compared them to an unmodified phosphodiester triplex-forming oligonucleotide (TFO1) and a TFO-nitrogen mustard conjugate (TFO2). PNA1 contains a + 2 charge and bound two adjacent 9-bp target sequences with high affinity and specificity, but only at low pH. PNA2 contains a +5 charge and bound one 11-bp target with high affinity up to pH 7.4, but with lower specificity. The PNA:DNA:PNA triplex formed by these cpy-bis-PNAs presented a stable barrier to DNA polymerase extension. The cpy-bis-PNAs and the TFO-alkylator conjugate prevented HER-2/neu transcription in a reporter gene assay (TFO2 = PNA1 > PNA2 >> TFO1). Both PNAs and TFOs were effective at binding the target sequence in naked genomic DNA, but only the TFO-alkylator (TFO2) and the more cationic PNA (PNA2) were detected at the endogenous HER-2/neu promoter in permeabilized cells. This work demonstrates the potential for preventing HER-2/neu gene expression with cpy-bis-PNAs in tumor cells.

BACKGROUND: proto-oncogene c-erbB-2 is located in chromosome 17 region q21 and codifies a 185 Kd protein, with tyrosine kinase activity. The amplification of this gene is associated with relapse and lower survival in breast cancer. Overexpression of this gene can be detected by immunohistochemistry (IHC). However, fluorescence in situ hybridization (FISH) and chromogenic in situ hybridization (CISH) allow the simultaneous analysis of morphology and overexpression of the gene. AIM: To evaluate the relationship of c-erbB-2 oncogene amplification measured by FISH with histological graduation, presence of positive Iymph nodes and evolution of breast cancer. PATIENTS AND METHODS: One hundred and ten tissue samples of invasive ductal or lobulillar breast cancer, positive for c-erbB-2 oncogene by IHC were analysed. The presence of c-erbB-2 oncogene amplification was subsequently analyzed by FISH. RESULTS: There was a significant association of c-erbB-2 amplification by FISH with pathological graduation of the tumor, number of regional Iymph nodes involved and disease free survival. CONCLUSIONS: proto-oncogene c-erbB-2 amplification is a good indicator of bad prognosis in invasive breast cancer.

An emerging paradigm holds that loss of negative signalling to receptor tyrosine kinases (RTKs) is permissive for their oncogenic activity. Herein, we have addressed tumor suppression by RALT/MIG-6, a transcriptionally controlled feedback inhibitor of ErbB RTKs, in breast cancer cells. Knockdown of RALT expression by RNAi enhanced the EGF-dependent proliferation of normal breast epithelial cells, indicating that loss of RALT signalling in breast epithelium may represent an advantageous condition during ErbB-driven tumorigenesis. Although mutational inactivation of the RALT gene was not detected in human breast carcinomas, RALT mRNA and protein expression was strongly and selectively reduced in ERBB2-amplified breast cancer cell lines. Reconstitution of RALT expression in ERBB2-amplified SKBr-3 and BT474 cells inhibited ErbB-2-dependent mitogenic signalling and counteracted the ability of ErbB ligands to promote resistance to the ErbB-2-targeting drug Herceptin. Thus, loss of RALT expression cooperates with ERBB2 gene amplification to drive full oncogenic signalling by the ErbB-2 receptor. Moreover, loss of RALT signalling may adversely affect tumor responses to ErbB-2-targeting agents.

BACKGROUND: Orlistat (Xenicaltrade mark), a US Food and Drug Administration (FDA)-approved drug for bodyweight loss, has recently been demonstrated to exhibit antitumor properties towards prostate cancer cells by virtue of its ability to block the lipogenic activity of fatty acid synthase (FAS). FAS (oncogenic antigen-519) is up-regulated in about 50% of breast cancers, is an indicator of poor prognosis, and has recently been functionally associated with the Her2/neu (erbB-2) oncogene. MATERIALS AND METHODS: We assessed the antitumoral effects of orlistat against the human breast cancer cell line SK-Br3, an in vitro paradigm of FAS and Her2/neu overexpression in breast cancer. RESULTS: Cell cycle analyses revealed that micromolar concentrations of orlistat induced, in a time- and dose-dependent manner, significant changes in the distribution of cell populations including a complete loss of G2-M phase, S-phase accumulation and a concomitant increase in the emerging sub-G1 (apoptotic) cells. Poly (ADP-ribose) polymerase (PARP) cleavage, an early event required for cells committed to apoptosis, was more predominant in orlistat-treated G1 phase cells. When we characterized signaling molecules participating in the cellular events following orlistat-induced inhibition of FAS activity and preceded inhibition of breast cancer cell proliferation, a dramatic down-regulation of Her2/neu-coded p185(Her2/neu) oncoprotein was found in orlistat-treated SK-Br3 cells (>90% reduction). Interestingly, a significant accumulation of the DNA-binding protein PEA3, a member of the Ets transcription factor family that specifically targets a PEA3-binding motif present on the Her2/neu gene promoter and down-regulates its activity, was observed in orlistat-treated SK-Br3 cells. When a Luciferase reporter gene driven by the Her2/neu promoter was transiently transfected in SK-Br3 cells, orlistat exposure was found to dramatically repress the promoter activity of Her2/neu gene, whereas a Her2/neu promoter bearing a mutated binding DNA sequence was not subject to negative regulation by orlistat, thus demonstrating that the intact PEA3 binding site on the Her2/neu promoter is required for the orlistat-induced transcriptional repression of Her2/neu overexpression. RNA interference (RNAi)-mediated silencing of FAS gene expression similarly repressed Her2/neu gene expression in a PEA3-dependent manner, thus ruling out a role for non-FAS orlistat-mediated effects. When the combination of orlistat and the anti-Her2/neu antibody trastuzumab (Herceptintrade mark) in either concurrent (orlistat + trastuzumab) or sequential (orlistat --> trastuzumab; trastuzumab --> orlistat) schedules was tested for synergism, addition or antagonism using the combination index (CI) method of Chou-Talalay, co-exposure of orlistat and trastuzumab demonstrated strong synergistic effects (CI10-90 = 0.110-0.847), whereas sequential exposure to orlistat followed by trastuzumab (CI10-90 = 0.380-1.210) and trastuzumab followed by orlistat (CI10-90 = 0.605-1.278) mainly showed additive or antagonistic interactions. Indeed, orlistat-induced FAS inhibition synergistically promoted apoptotic cell death when concurrently combined with trastuzumab as determined by an ELISA for histone-associated DNA fragments. Importantly, the degree of FAS expression in a panel of human breast cancer cell lines was predictive of sensitivity to orlistat-induced anti-proliferative effects as determined by a MTT-based characterization of metabolically viable breast cancer cells. Moreover, hypersensitivity to orlistat-induced cytotoxicity was observed in MCF-7 breast cancer cells engineered to overexpress Her2/neu (MCF-7/Her2-18 cells), which exhibit a significant up-regulation of FAS expression and activity. CONCLUSIONS: These findings reveal that the development of more potent and/or bioavailable orlistat s variants targeting the lipogenic activity of FAS may open a novel therapeutic avenue for treating Her2/neu-overexpressing breast carcinomas.

HER-2/neu is an oncogene located on chromosome 17, encoding a type 1 tyrosine kinase growth factor receptor. HER-2/neu is overexpressed in 25-30% of breast cancers, increasing the aggressiveness of the tumor. We describe HER-2/neu overexpression and her-2/neu oncogene amplification in a case of uterine carcinosarcoma occurring in a 46-year-old women who had undergone mastectomy and a 2-year postoperative treatment with tamoxifen for invasive breast cancer. This is the first study demonstrating HER-2/neu expression and her-2/neu oncogene amplification in a uterine carcinosarcoma that has developed in a patient given tamoxifen therapy. It still needs to be clarified whether HER-2/neu overexpression increases the aggressiveness of carcinosarcoma, or whether HER-2/neu has a direct role in its pathogenesis, as described in breast cancers. Our observation of the her-2/neu oncogene amplification does not shed light on the prognostic impact of uterine carcinosarcoma following tamoxifen therapy, but it may indicate the need for further studies of HER-2/neu overexpression in a larger series of uterine carcinosarcoma patients, and it may permit us to hypothesize about a therapeutic concept, including the inhibition of HER-2/neu by humanized monoclonal antibodies also in uterine carcinosarcoma patients.

Omega-3 polyunsaturated fatty acid (PUFA), docosahexaenoic acid (DHA; 22:6n-3) and other omega-3 and omega-6 PUFAs have raised interest as novel anticancer agents by exerting selective cytotoxic effects on human cancer cells without affecting normal tissues. Here, we examined the in vitro relationship between exogenous supplementation with DHA and breast cancer chemosensitivity to taxanes. We measured cell viability in the highly metastatic human breast cancer cell line MDA-MB-231 exposed sequentially to DHA followed by paclitaxel (Taxol) or docetaxel (Taxotere). As DHA by itself showed cytotoxic effects, possible synergistic interactions between DHA and taxanes were assessed, employing the combination index (CI) method and the isobologram analysis. Both methods showed a strong synergism (CI approximately 0.5; P<0.005) between DHA and taxanes in MDA-MB-231 cells. When the increase in taxanes efficacy was measured by dividing the IC50 values (50% inhibitory concentrations) obtained when the cells were exposed to taxanes alone by those after DHA pre-exposure, we found that DHA enhanced the cytotoxic activity of taxanes against MDA-MB-231 cells in a dose-dependent manner (up to 13- and 5-fold increase in Taxol and Taxotere efficacy, respectively). Importantly, sequential exposure to DHA followed by taxanes also yielded strong synergism in Her-2/neu (c-erbB-2)-overexpressing and taxanes-resistant SK-Br3 and BT-474 breast cancer cells. Moreover, exogenous supplementation with DHA significantly decreased the expression of Her-2/neu-codified p185(Her-2/neu) oncoprotein (up to 78% reduction in BT-474 cells). Our results provide experimental support to the hypothesis that omega-3 PUFAs can be used as modulators of tumor cell chemosensitivity and provide the rationale for in vivo preclinical investigation. In addition, this is the first study demonstrating that omega-3 PUFA DHA downregulates Her-2/neu oncogene expression in human breast cancer cells.

OBJECTIVES: To investigate whether pleural levels of the soluble oncoprotein 185 HER-2 (sp185(HER-2)), individually or in combination with CEA and CA 15-3, were useful for the diagnosis of malignant effusions. DESIGN AND METHODS: Levels of CEA, CA 15-3, and sp185(HER-2) were measured in the pleural fluid from 135 malignant and 103 benign effusions. Thresholds of these tumor markers were chosen for a diagnostic specificity of >or=99%. RESULTS: Pleural sp185(HER-2) levels greater than 25 ng/mL were observed in 20% of breast and 10% of lung adenocarcinomas, and predicted a malignant effusion with a sensitivity of 7% and a likelihood ratio of 7.6. Combination of CEA and CA 15-3 resulted in 50% sensitivity, while adding sp185(HER-2) to this panel nonsignificantly increased sensitivity by 5% (P = 0.45). Only 1 patient with breast adenocarcinoma among 45 cytology-negative malignant effusions had sp185(HER-2) above the diagnostic cutoff point. CONCLUSION: Measurement of pleural fluid sp185(HER-2) has poor diagnostic performance in patients with malignant effusions.

49 breast cancer tissues were investigated by imunnohistochemical method, to reveal the expression and distribution of the oncoprotein HER-2/neu. It was found, that expression of the oncoprotein HER-2/neu in the tumor tissues is very variable, which depends on the cancer histogenesis, histological form, differentiation and stage of tumor development. Intensity of expression of the oncoprotein HER-2/neu is higher in the ductal forms of the cancer, there is reciprocal relationship between the intensity of the expression of the oncoprotein HER-2/neu and steroid hormones. Using these data we can define histogenesis, rate of maturation and other tumor features in more objective manner. This is very important for selection of the breast cancer treatment methods.

INTRODUCTION: The HER2/neu proto-oncogene encodes a transmembrane receptor protein involved in the development and progression of the majority of cancers. Prior studies have shown that HER2/neu oncogene is overexpressed in approximately 15-30% of ovarian carcinomas. However findings regarding the overexpression and prognosis are still conflicting. METHODS: Our retrospective study was performed on 194 ovarian carcinoma tissues obtained at the time of first surgery. The staining procedure for HER2/neu overexpression was performed using a polyclonal antibody. RESULTS: HER2/neu overexpression was found in 53 out of 194 (27.3%) investigated cases of which 26 (13.4%) carcinomas were weakly positive (score 1+) and 27 (13.9%) moderately (score 2+) to intensely positive (score 3+). No significant relationship was found between HER2/neu score and main clinical and pathological features. Significant difference in overall survival was evident between negative women (0/1+) and positive women (2+/3+): 48 and 29 months, respectively (p = 0.04). In multivariate analysis HER2/neu overexpression appeared to be the only variable significantly correlated with progression and death. CA125 normalization at 3 and 6 months appeared a strong predictor of progression and survival. CONCLUSION: In this study HER2/neu overexpression was associated with an increased risk of progression and death, especially among women with FIGO Stage I and II ovarian carcinoma.

BACKGROUND: Overexpression of the epidermal growth factor type II receptor HER-2/neu has been associated with resistance to chemotherapy and poor survival in several human tumors. In the current study, the authors have determined the frequency and clinical significance of HER-2/neu gene amplification in uterine serous papillary endometrial carcinoma (USPC), a highly aggressive variant of endometrial carcinoma. METHODS: Fluorescence in situ hybridization (FISH) assay was used to analyze gene amplification in paraffin blocks from 30 women harboring Stage IA-IV USPC treated at the University of Arkansas for Medical Sciences (Little Rock, AR) from 1997 to 2004. Chromosome 17 polysomy status by FISH was also assessed in ALL specimens. USPC patient survival in relation to HER-2/neu gene amplification was analyzed using Kaplan-Meier curves in conjunction with the log-rank test. RESULTS: Amplification of the HER-2/neu gene by FISH was observed in 14 of the 30 (47%) cases. Heterogeneity was noted in 4 of 14 cases in the amplification of the HER-2/neu gene within the same tumor samples with pockets of amplified tumor cells amidst nonamplified tumor cells. Patients with USPC harboring tumors with HER-2/neu gene amplification had a significantly shorter survival time from diagnosis to disease-related death when compared with FISH-negative patients (P = 0.0008). African-American (AA) patients were found to have a poorer prognosis compared with Caucasian (C) women (P = 0.01) and to harbor USPC with significantly higher levels of HER-2/neu gene amplification (P = 0.02). CONCLUSIONS: HER-2/neu gene amplification in USPC was found to be an important prognostic indicator for poor outcome that occurs more frequently in AA when compared with C patients. Determination of HER-2/neu gene amplification may guide clinical management of patients with USPC and may have important implications for the implementation of novel treatment strategies.

Recombinant antibody fragments represent useful tools for cancer diagnosis and therapy. Aberrant expression of the HER2 receptor is implicated in metastatic breast and ovary cancers, two malignancies with a high prevalence in young women. In this study, we focussed on a single-chain fragment of variable antibody regions specific for HER2 (scFv800E6) that can be expressed in a functional form in the cytoplasm of Escherichia coli. ScFv800E6 was extracted from bacterial cultures following induction at different temperatures and purified. The yield of both soluble and insoluble forms was measured. We found that scFv800E6 was functional when expressed in the soluble fraction in the bacteria cytosol. In addition, scFv800E6 extracted from inclusion bodies was easily refolded and largely recovered its functionality. Thus, scFv800E6 is intrinsically capable of efficient and functional folding in a reducing environment and represents one of the few described antibody fragments with a framework well adapted for cytoplasmic expression.

Recombinant antibody fragments represent useful tools for cancer diagnosis and therapy. Aberrant expression of the HER2 receptor is implicated in metastatic breast and ovary cancers, two malignancies with a high prevalence in young women. In this study, we focussed on a single-chain fragment of variable antibody regions specific for HER2 (scFv800E6) that can be expressed in a functional form in the cytoplasm of Escherichia coli. ScFv800E6 was extracted from bacterial cultures following induction at different temperatures and purified. The yield of both soluble and insoluble forms was measured. We found that scFv800E6 was functional when expressed in the soluble fraction in the bacteria cytosol. In addition, scFv800E6 extracted from inclusion bodies was easily refolded and largely recovered its functionality. Thus, scFv800E6 is intrinsically capable of efficient and functional folding in a reducing environment and represents one of the few described antibody fragments with a framework well adapted for cytoplasmic expression.

The treatment options for synovial sarcoma (SS) are very limited, though this type of sarcoma seems to be more heterogeneous than it has been traditionally considered. The present study investigates the Her-2 oncogene status of 20 cases of SS, to determine whether Her-2 amplification can be considered as a prognostic factor. Her-2 oncogene amplification was determined on smears (frozen material was used from our tumor bank in each case), using fluorescence in situ hybridization technique (dual color FISH with centromeric probe for chromosome 17 and specific probe for Her-2 oncogene). Moreover, protein expression was assessed by immunohistochemistry, and DNA ploidy status was measured using image analysis. We had 5 biphasic and 15 monophasic SSs, patients age ranged from 13 to 68 years (mean, 39.8 years). tumor size was larger than 5 cm in each case. Follow-up time ranged from 6 to 78 months (mean, 38.5 months). For statistical analysis the chi-square test was used. Her-2 oncogene amplification was found in three cases (15.0%) of 20 SSs. These cases proved to be 2+ positive by immunohistochemistry, but massive amplification, characteristic of a subset of breast carcinomas, was not observed. Her-2 oncogene amplification was significantly associated with a lower risk of developing metastasis (P<0.05) (none of the 3 amplified cases had metastases), while no association was found with recurrence. Six cases proved to be aneuploid and 14 were diploid, but no association was found between Her-2 amplification status and ploidy, and between ploidy status and metastasis or recurrence. Our results emphasize and confirm that Her-2 oncogene amplification is a rare event in SS, but the small subset of SS with Her-2 amplification has a better overall prognosis. Furthermore, this may open a theoretically new treatment possibility with Trastuzumab for Her-2-amplified cases of SS.

The omega-6 polyunsaturated fatty acid gamma-linolenic acid (GLA; 18:3n-6), which is found in several plant oils and is used as an herbal medicine, has antitumor activity in vitro. We examined the effect of GLA on the expression of the Her-2/neu (erbB-2) oncogene, which is involved in development of numerous types of human cancer. Flow cytometric and immunoblotting analyses demonstrated that GLA treatment substantially reduced Her-2/neu protein levels in the Her-2/neu-overexpressing cell lines BT-474, SK-Br3, and MDA-MB-453 (breast cancer), SK-OV3 (ovarian cancer), and NCI-N87 (gastrointestinal tumor derived). GLA exposure led to a dramatic decrease in Her-2/neu promoter activity and a concomitant increase in the levels of polyomavirus enhancer activator 3 (PEA3), a transcriptional repressor of Her-2/neu, in these cell lines. In transient transfection experiments, a Her-2/neu promoter bearing a PEA3 site-mutated sequence was not subject to negative regulation by GLA in Her-2/neu-overexpressing cell lines. Concurrent treatments of Her-2/neu-overexpressing cancer cells with GLA and the anti-Her-2/neu antibody trastuzumab led to synergistic increases in apoptosis and reduced growth and colony formation.

PURPOSE: Altered resident cellular genetic sequences (oncogenes) may result in malignant transformation, maintenance of tumor growth, and metastatic propensity. In this pilot study, we have elected to probe c-myc oncogene in evaluating specimens from human squamous cell carcinoma. MATERIALS AND METHODS: Samples were obtained from 24 patients with squamous cell carcinoma of the head and neck. The ratio of tumor DNA values to that of control DNA was used to estimate the c-myc copy number. RESULTS: Data from material obtained from eight patients was analyzed to the point of c-myc copy number. tumors varied from stage II through IV. Five originated in the oral cavity and three in the larynx. Analysis of primary tumors demonstrated that two of eight had increased c-myc copy numbers. Histologically positive neck specimens were encountered in five of the study patients. Three demonstrated elevated c-myc copy numbers, two of which had had increased copy number at the primary site. CONCLUSION: This study confirms that c-myc amplification can be present in squamous cell carcinoma of the head and neck. c-myc Amplification may also be present in neck metastasis. oncogene amplification in neck metastasis may indicate an increased metastatic propensity for individual tumor cells demonstrating c-myc amplification.

The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression. We demonstrate that focal adhesion kinase (FAK) is essential for oncogenic transformation and cell invasion that is induced by ErbB-2 and -3 receptor signaling. ErbB-2/3 overexpression in FAK-deficient cells fails to promote cell transformation and rescue chemotaxis deficiency. Restoration of FAK rescues both oncogenic transformation and invasion that is induced by ErbB-2/3 in vitro and in vivo. In contrast, the inhibition of FAK in FAK-proficient invasive cancer cells prevented cell invasion and metastasis formation. The activation of ErbB-2/3 regulates FAK phosphorylation at Tyr-397, -861, and -925. ErbB-induced oncogenic transformation correlates with the ability of FAK to restore ErbB-2/3-induced mitogen-activated protein kinase (MAPK) activation; the inhibition of MAPK prevented oncogenic transformation. In contrast, the inhibition of Src but not MAPK prevented ErbB-FAK-induced chemotaxis. In migratory cells, activated ErbB-2/3 receptors colocalize with activated FAK at cell protrusions. This colocalization requires intact FAK. In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

AIM: The invasive mammary cancer is the most frequent malign tumor of a woman. Among the potential prognostic factors are included the biomarkers which measure or are associated with biological processes involved in the tumoral progression. We study the prognostic importance of the c-erbB2 oncoprotein in the invasive mammary cancer. MATERIAL AND METHODS: We included in the study 56 female patients suffering of invasive mammary cancer. The tissue fragments were fitted in formol, included to paraffin, commonly colored haematoxylin-eosine (HE); for the determination of the c-erbB2 we used the immunohistochemical method of avidin-biotin (ABC) complex. RESULTS: From the total of 56 tumors, 38 (67.9%) presented different degrees of positivity; 18 (32.1%) did not express the oncoprotein c-erbB2. CONCLUSIONS: The positivity of c-erbB2 oncoprotein was correlated with the size of the tumor; the carcinomas which are not infiltrative ductal, knows as having a better prognostic, were c-erbB2 negative.

Determination of Her-2/neu oncogene amplification is important in the current treatment of breast carcinoma. In addition to fluorescence in situ hybridization (FISH) and immunohistochemical stain (HercepTest), chromogenic in situ hybridization (CISH) has been shown to be a sensitive and specific method to determine the Her-2/neu status of surgical specimens. The effectiveness of CISH in detecting the Her-2/neu oncogene in cytologic specimens has not been well documented. Twenty-five cases of fine needle aspirate smears and touch imprints from infiltrating ductal carcinomas were examined. Both CISH and FISH were performed on each case using a digoxigenin-labeled Her-2 DNA probe for CISH (Zymed) and both Her-2 and chromosome 17 probes for FISH (Vysis). Sixty tumor cells were evaluated in each case. The scoring system and interpretation of CISH were as follows: (1) no amplification (<5 brown dots/nucleus), (2) amplification (>10 brown dots/nucleus), and (3) low-level amplification (5-9 brown dots/nucleus). Of the 25 cases analyzed, 23 (3 amplified and 20 nonamplified) showed similar results for both methods. Two cases were discordant. In these cases, low-level amplification was suggested by CISH but nonamplification by FISH. One of the cases can be explained by polysomy for chromosome 17 by FISH. In conclusion, our preliminary data suggest that CISH is a useful technique to determine Her-2/neu oncogene status in cytologic specimens. In a case of low-level amplification, a CISH chromosome 17 probe should be used, or FISH is recommended for confirmation.

There have long been indications of a role for PI3K (phosphatidylinositol 3-kinase) in cancer pathogenesis. Experimental data document a requirement for deregulation of both transcription and translation in PI3K-mediated oncogenic transformation. The recent discoveries of cancer-specific mutations in PIK3CA, the gene that encodes the catalytic subunit p110alpha of PI3K, have heightened the interest in the oncogenic potential of this lipid kinase and have made p110alpha an ideal drug target.

The HER-2/neu oncogene (a member of the Erb-like oncogene family) is distinct from but closely related to the c-erb B gene which encodes the epidermal growth factor receptor (EGFr). HER-2/neu gene amplification was found in a large number of mammary carcinomas and there was a strong correlation between this phenomenon and poor prognosis. In our study HER-2/neu oncogene expression was determined in 16 malignant ovarian tumors, 2 ovarian lymphomas and 5 normal ovaries. The HER-2/neu gene was found both in normal ovaries and malignant tumors, without any apparent difference among the various histological types. In ALL the specimens examined, HER-2/neu expression did not seem to be related to EGF binding capacity.

AIMS: c-erbB-2 overexpression has been shown to be a potential marker of aggressive biological behaviour in a varity of tumours, whereas its role played in thyroid papillary thyroid carcinoma (PTC) remains unclear. Objective of the study is to determine whether c-erbB-2 overexpression correlates with the clinical course. METHODS: We have studied 32 PTC by a two-step immunocytochemical staining procedure for paraffin-embedded specimens (DAKO Hercep-Test). Semiquantitative evaluations were performed, based on the intensity of immunostaining and the percentage of tumor cells. RESULTS: 34% (11/32) of the PTC showed a membranous overexpression of the HER2/neu oncoprotein. Correlating the pathological and clinical data revealed that 81% (9/11) c-erbB-2 positive patients and only 33% (7/21) c-erbB-2 negative patients developed a tumor recurrence or a progression (p = 0.02 in Fisher s exact test). 3/11 c-erbB-2 positive patients died from PTC whereas ALL (21/21) c-erbB-2 negative patients are still alive (p = 0.03). CONCLUSIONS: Our results strongly suggest that c-erbB-2 oncoprotein overexpression is related to the clinical course of PTC.

NEU (ERBB2) and other members of the epidermal growth factor receptor (EGFR) family have been implicated in human prostate cancer (CAP) development and progression to an androgen-independent state, but the extent of involvement and precise role of this signaling pathway remain unclear. To begin addressing such open questions in an animal model, we have developed a transgenic line in which an oncogenic Neu cDNA (Neu*) driven by the probasin gene promoter is overexpressed in the mouse prostate and causes development of prostatic intraepithelial neoplasia (PIN) that progresses to invasive carcinoma. expression profiling using microarrays, which was selectively validated and extended by immunophenotyping of Neu*-induced PIN and CAP, led to the identification of some novel biomarkers and also revealed increased expression of Egfr, Erbb3 and phosphorylated androgen receptor. In view of this information from our mouse model, which can be used to analyze further the role of Erbb signaling in prostatic tumorigenesis, we examined human prostate cancer tissue arrays by immunohistochemistry. Based on statistical analyses of the results, we propose the testable hypothesis that ERBB3, shown to be expressed in 86% of the human CAP cases that we examined, is the pivotal element of the Erbb pathway promoting tumorigenesis by heterodimerization with NEU or EGFR, while a NEU/EGFR dimer does not appear to play a significant role in CAP.

Olive oil is an integral ingredient of the "Mediterranean diet" and accumulating evidence suggests that it may have a potential role in lowering risk of several cancers. We recently hypothesized that the anti-cancer actions of olive oil may relate to its monounsaturated fatty acid (MUFA) oleic acid (OA; 18:1n-9) content to specifically regulate oncogenes. In this study, transient transfection experiments with human Her-2/neu promoter-driven luciferase gene established the ability of OA to specifically repress the transcriptional activity of Her-2/neu gene. Gene repression was seen in tumour-derived cell lines with Her-2/neu gene amplification and overexpression, including SK-Br3 (56% reduction), SK-OV3 (75% reduction) and NCI-N87 (55% reduction) breast, ovarian and stomach cancer cell lines, respectively. Also marginal decreases in promoter activity were observed in cancer cells expressing physiological levels of Her-2/neu (20% reduction in MCF-7 breast cancer cells). Remarkably, OA treatment in Her-2/neu-overexpressing cancer cells was found to induce up-regulation of the Ets protein polyomavirus enhancer activator 3 (PEA3), a transcriptional repressor of Her-2/neu promoter. Also, an intact PEA3 DNA-binding-site at endogenous Her-2/neu gene promoter was essential for OA-induced repression of this gene. Moreover, OA treatment failed to decrease Her-2/neu protein levels in MCF-7/Her2-18 transfectants, which stably express full-length human Her-2/neu cDNA controlled by a SV40 viral promoter. OA-induced transcriptional repression of Her-2/neu through the action of PEA3 protein at the promoter level may represent a novel mechanism linking "Mediterranean diet" and cancer.

Molecular dynamics (MD) simulations of proteins in a lipid bilayer environment are usually undertaken with one or a few starting structures. Here we report a search protocol for systematically exploring the possible interactions in helical bundle transmembrane proteins, a frequently occurring structural motif. The search protocol correctly identifies the experimentally known structure of the dimeric human glycophorin A transmembrane domain as the lowest energy structure among five different models without any prior assumptions, whilst an identical in vacuo search fails to identify the correct structure. The lowest energy structure from the search in a lipid bilayer has a root mean square deviation of 1.1A to the experimental structure. We have applied the same search protocol to the unknown transmembrane structure of the oncogenic mutant ErbB-2 protein, a member of the family of epidermal growth factor receptors. Resulting structures show the role of glutamic acid hydrogen bonding and close helical packing. Water molecules may also play a key role in stabilisation of the transmembrane helix association.

Mucoepidermoid carcinomas (MECs) of the salivary and bronchial glands are characterized by a recurrent t(11;19)(q21;p13) translocation resulting in a MECT1-MAML2 fusion in which the CREB-binding domain of the CREB coactivator MECT1 (also known as CRTC1, TORC1 or WAMTP1) is fused to the transactivation domain of the Notch coactivator MAML2. To gain further insights into the molecular pathogenesis of MECs, we cytogenetically and molecularly characterized a series of 29 MECs. A t(11;19) and/or an MECT1-MAML2 fusion was detected in more than 55% of the tumors. Several cases with cryptic rearrangements that resulted in gene fusions were detected. In fusion-negative MECs, the most common aberration was a single or multiple trisomies. Western blot and immunohistochemical studies demonstrated that the MECT1-MAML2 fusion protein was expressed in ALL MEC-specific cell types. In addition, cotransfection experiments showed that the fusion protein colocalized with CREB in homogeneously distributed nuclear granules. Analyses of potential downstream targets of the fusion revealed differential expression of the cAMP/CREB (FLT1 and NR4A2) and Notch (HES1 and HES5) target genes in fusion-positive and fusion-negative MECs. Moreover, clinical follow-up studies revealed that fusion-positive patients had a significantly lower risk of local recurrence, metastases, or tumor-related death compared to fusion-negative patients (P = 0.0012). When considering tumor-related deaths only, the estimated median survival for fusion-positive patients was greater than 10 years compared to 1.6 years for fusion-negative patients. These findings suggest that molecularly classifying MECs on the basis of an MECT1-MAML2 fusion is histopathologically and clinically relevant and that the fusion is a useful marker in predicting the biological behavior of MECs.

Surgery is the treatment of choice for uterine carcinosarcomas; nevertheless, the poor effect of chemotherapy and radiotherapy represents an insidious problem for patients with metastatic or unresectable disease, and indeed, new therapeutic approaches are clearly required to improve survival of uterine carcinosarcoma patients. The HER-2 oncogene, located on chromosome 17, encodes for a tyrosine kinase growth factor receptor. We analyzed HER-2/neu overexpression by immunohistochemistry in 28 uterine carcinosarcomas. HER-2/neu amplification with fluorescence in situ hybridization (FISH) was tested in positive cases. The expression of HER-2/neu was correlated with disease-free interval and survival (Kaplan-Meier estimates). We observed HER-2/neu overexpression in nine cases (32.1%) and HER-2/neu amplification in ALL the four HER-2/neu 3+ score positive cases tested by FISH. HER-2/neu expression was not correlated with clinical outcome. Patients with disease limited to the uterus (stages I-II) displayed a significantly better disease-free survival (P= 0.004) and actuarial survival (P= 0.01). Demonstration of HER-2/neu overexpression and amplification in uterine carcinosarcoma may represent the first rationale step for further investigations. Hence, the results of this analysis may support the challenge of a new therapeutic approach, which could test the role of anti-HER-2 (trastuzumab) in patients with advanced or metastatic uterine carcinosarcoma.

INTRODUCTION: Amplification of the HER-2 receptor tyrosine kinase has been implicated in the pathogenesis and aggressive behavior of approximately 25% of invasive human breast cancers. Clinical and experimental evidence suggest that aberrant HER-2 signaling contributes to tumor initiation and disease progression. Transforming growth factor beta (TGF-beta) is the dominant factor opposing growth stimulatory factors and early oncogene activation in many tissues, including the mammary gland. Thus, to better understand the mechanisms by which HER-2 overexpression promotes the early stages of breast cancer, we directly assayed the cellular and molecular effects of TGF-beta1 on breast cancer cells in the presence or absence of overexpressed HER-2. METHODS: Cell proliferation assays were used to determine the effect of TGF-beta on the growth of breast cancer cells with normal or high level expression of HER-2. Affymetrix microarrays combined with Northern and western blot analysis were used to monitor the transcriptional responses to exogenous TGF-beta1 in luminal and mesenchymal-like breast cancer cells. The activity of the core TGF-beta signaling pathway was assessed using TGF-beta1 binding assays, phospho-specific Smad antibodies, immunofluorescent staining of Smad and Smad DNA binding assays. RESULTS: We demonstrate that cells engineered to over-express HER-2 are resistant to the anti-proliferative effect of TGF-beta1. HER-2 overexpression profoundly diminishes the transcriptional responses induced by TGF-beta in the luminal MCF-7 breast cancer cell line and prevents target gene induction by a novel mechanism that does not involve the abrogation of Smad nuclear accumulation, DNA binding or changes in c-myc repression. Conversely, HER-2 overexpression in the context of the mesenchymal MDA-MB-231 breast cell line potentiated the TGF-beta induced pro-invasive and pro-metastatic gene signature. CONCLUSION: HER-2 overexpression promotes the growth and malignancy of mammary epithelial cells, in part, by conferring resistance to the growth inhibitory effects of TGF-beta. In contrast, HER-2 and TGF-beta signaling pathways can cooperate to promote especially aggressive disease behavior in the context of a highly invasive breast tumor model.

The oncogene BRAF(V600E) is the most frequent genetic event in papillary thyroid carcinoma (PTC) but its prognostic impact still remains to be elucidated. We evaluated a representative series of 67 individuals with PTC who underwent total thyroidectomy. BRAF-positive tumours correlated with early recurrences (32% vs 7.6%; P=0.02) during a median postoperative follow-up period of 3 years. Interestingly, within the recurrences, a significant majority had negative radioiodine ((131)I) total body scans, predicting a poorer outcome as treatment with (131)I is not effective. This last observation led us to investigate the role of BRAF(V600E) and the MEK-ERK pathway in thyroid dedifferentiation, particularly in Na(+)/I(-) symporter (NIS) impairment, as this thyroid-specific plasma membrane glycoprotein mediates active transport of I(-) into the thyroid follicular cells. A subset of 60 PTC samples was evaluated for NIS immunoreactivity and, accordingly, we confirmed a significant low NIS expression and impaired targeting to membranes in BRAF-positive samples (3.5% vs 30%; P=0.005). Furthermore, experiments with differentiated PCCl3 thyroid cells demonstrated that transient expression of BRAF(V600E) sharply impaired both NIS expression and targeting to membrane and, surprisingly, this impairment was not totally dependent on the MEK-ERK pathway. We have concluded that BRAF(V600E) is a new prognostic factor in PTC that correlates with a high risk of recurrences and less differentiated tumours due to the loss of NIS-mediated (131)I uptake.

In a thyroid hormone-sensitive mouse preadipocyte cell line (Ob 17), the concentration of nuclear T3 receptors increases during differentiation in an insulin-independent manner and decreases by 50-60 p.cent after medium supplementation with physiological concentrations of T3. The down-regulation of T3 receptors implies both quantitative and qualitative changes. The preadipocyte T3 receptors were previously reported to be heterogeneous in gel filtration and in their reactivity towards rabbit antibodies raised against large erb A alpha peptides. This report shows that the receptor heterogeneity is not modified during cell development, whereas T3 mainly depletes the receptor species that are both the most retarded in gel filtration and preferentially recognized by c-erb A alpha-specific antisera. The c-erb A alpha-related T3 receptors which predominate in preadipocytes, are thus probably mainly involved in receptor depletion by T3. A similar T3 receptor half-life of 12-13 h was estimated after cycloheximide addition to cells at confluence or later in the differentiation phase with or without T3. This suggested that development, or T3, might have mainly affected the production of T3 receptors. In Northern hybridization studies, using alpha- or beta-type c-erb A cDNA probes containing the entire coding sequence, only alpha-type mRNAs were detected with a predominant band of 2.8 kbases and two fainter bands of about 5.5 and 6.0 kbases. The alpha-type mRNA abundance relative to beta-actin significantly increased during differentiation and decreased after T3 addition.

To investigate the mechanisms through which p130Cas adaptor protein is linked to tumorigenesis, we generated mouse mammary tumor virus (MMTV)-p130Cas mice overexpressing p130Cas in the mammary gland. MMTVp130Cas transgenic mice are characterized by extensive mammary epithelial hyperplasia during development and pregnancy and by delayed involution at the end of lactation. These phenotypes are associated with activation of Src kinase, extracellular signal-regulated kinase 1/2, mitogen-activated protein kinase, and Akt pathways, leading to an increased rate of proliferation and a decreased apoptosis. A double-transgenic line derived from crossing MMTV-p130Cas with MMTV-HER2-Neu mice expressing the activated form of the HER2-Neu oncogene develops multifocal mammary tumors with a significantly shorter latency than the HER2-Neu parental strain alone. Mammary epithelial cells isolated from tumors of double-transgenic mice display increased tyrosine phosphorylation, c-Src, and Akt activation compared with cells derived from HER2-Neu tumors. In addition, p130Cas down-regulation by RNA interference increases apoptosis in HER2-Neu-expressing cells, indicating that p130Cas regulates cell survival. Consistently with the double-transgenic mice model, p130Cas is overexpressed in a significant subset of human breast cancers and high levels of p130Cas in association with HER2 expression correlate with elevated proliferation. These findings provide evidences for a role of p130Cas as a positive regulator of both proliferation and survival in normal and transformed mammary epithelial cells. Its overexpression contributes to HER2-Neu-induced breast tumorigenesis, thus identifying this protein as a putative target for clinical therapy.

The expression of the VAV proto-oncogene in 57 patients with chronic myeloproliferative disease (CMD), B-cell acute lymphoblastic leukaemia (B-ALL) and B-cell non-Hodgkin Lymphoma (B-NHL), and 61 with B-cell chronic lymphocytic leukaemia (B-CLL) was analysed. VAV overexpression was observed in 19.5% of cases and 81% of VAV-positive tumours also displayed VAV phosphorylation. Overexpression was not observed in B-ALL or CMD, but 13% of B-NHL and 34.4% of B-CLL patients (P = 0.002) overexpressed VAV. The overexpression and phosphorylation of VAV was detected more frequently in 13q- chronic lymphocytic leukaemias (71.4%) versus other B-CLLs (23.4%, P = 0.001). Overexpression of VAV protein is a frequent event in patients with B-CLL displaying loss of 13q sequences.

The adenovirus type 5 early region 1A (E1A) gene was introduced into neu-transformed B104-1-1 cells. Cells that expressed E1A possessed reduced transforming activity in vitro and reduced tumorigenicity in nude mice. These results demonstrate that the E1A gene products can act negatively to suppress the transformed phenotype in neu-transformed cells.

The E3 region of adenovirus induces down-regulation of epidermal growth factor receptor (EGFR) through endocytosis. Here we report that an EGFR-related protein, the HER-2/c-erbB-2 gene product, p185, is also down-regulated by adenovirus, but via a different mechanism. We found that the adenovirus E1a gene is responsible for the repression of HER-2/c-erbB-2 at the RNA level.

Sections of formalin-fixed, paraffin-embedded primary salivary gland tumours were stained with a monoclonal antibody to the c-erbB-2 oncoprotein to determine the incidence and significance of expression of this protein. The series of 131 tumours comprised 33 cases of pleomorphic adenoma, 2 of malignant mixed tumour, 1 oxyphil adenoma, 31 Warthin s tumours, 4 basal cell adenomas, 6 mucoepidermoid carcinomas, 14 acinic cell carcinomas, 19 adenoid cystic carcinomas, 3 squamous carcinomas, and 18 poorly differentiated adenocarcinomas. Positive staining, as defined in previous studies, was present in five tumours (three cases of poorly differentiated adenocarcinoma, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma). A review of the medical records of ALL patients did not disclose any clear difference between the clinical behaviour of positive and negative cases over a period of follow-up that ranged from 18 to 120 months. The findings of this study indicate that the protein product of the c-erbB-2 proto-oncogene is infrequently expressed in salivary gland tumours, and when it is localized on the tumour cell surface membrane, there is no clear evidence that this determines the biological behaviour of the tumour.

The avian erythroblastosis virus v-erbA oncogene is imprecisely derived from a cellular gene (c-erbA) encoding a thyroid hormone receptor: the v-erbA protein has sustained both small terminal deletions and internal amino acid sequence changes relative to c-erbA. We report here that one of these missense differences between v- and c-erbA proteins, located in a zinc finger DNA binding domain, has dramatic effects on the biological activities of the encoded protein. Back mutation of the viral coding sequence to resemble c-erbA at this site severely impairs erythroid transformation and produces subtle changes in DNA binding by the encoded protein, suggesting that differences in DNA binding by the viral and cellular proteins may be involved in the activation of v-erbA as an oncogene.

Immunoreactivity for c-erbB-2 oncogene product expression has been investigated in patients with breast cancer using the polyclonal antibody 21N. Three series of patients were studied, 602 presenting with primary operable cancer, 57 with stage 3 and 123 with stage 4 disease. Representative tissue sections of each primary tumour were stained using a standard immunoperoxidase technique. Invasive tumour membrane immunoreactivity was assessed and identified in 15% of patients with primary operable cancer and 20% in the advanced breast cancer group. The results demonstrate a relationship between poorer survival and oncogene expression in ALL three patient groups. Patients in the primary operable cancer group with membrane oncoprotein expression had a poorer outcome, 35% 10-year survival, compared with those in which membrane expression was absent, 55% 10-year survival. The median survival of patients with stage 3 disease with c-erbB-2 membrane positivity was 17 months compared to 24 months with membrane negativity. In stage 4 disease median survival with membrane expression was 8.8 months compared to 19.7 months with no membrane expression. In addition in the series of primary cancers a correlation existed between histological grade and membrane immunoreactivity. Multivariate analysis showed histological grade to be a more powerful prognostic factor than c-erbB-2 protein expression. In conclusion, this study demonstrates, in a large series of patients presenting to one centre, that c-erbB-2 protein expression is a prognostic indicator in patients with primary operable and advanced breast disease.

In a previous series we have shown poor short-term (3-5 years) survival for patients with tumours overexpressing the c-erbB-2 oncoprotein. In this study we employed archival paraffin-embedded tissue from patients who underwent mastectomy 10-12 years prior to assessment (n = 187). Immunohistochemical staining was carried out by an indirect immunoperoxidase technique using the novel monoclonal antibody NCL-CB11. tumours were scored according to intensity of membrane staining. Patient and tumour information was obtained by scrutiny of clinical records. Survival analysis was carried out for both time to relapse and time to death, using the log rank test. Patients with tumours demonstrating intense membrane staining had a poor prognosis compared with the rest, with a steeply sloped survival curve over the first 4 years; the survival difference was still evident at 12 years follow-up (P less than 0.001). The survival advantage for c-erbB-2 negative patients was maintained in lymph node negative patients (P less than 0.001). However, c-erbB-2 status did not influence survival in the node positive group, where ALL patients had a uniformly poor outlook. These results applied to both time to relapse and time to death. In conclusion, c-erbB-2 status, determined using NCL-CB11, is a powerful prognostic indicator, defining in particular node negative patients with a particularly poor prognosis, and for whom alternative therapeutic strategies may be appropriate.

An antigen, immunologically related to the external domain of the c-erbB-2 (HER-2/neu) protein, was found shed into the serum of nude mice bearing tumors that overexpress the c-erbB-2 protein (gp185). Utilizing paired combinations from a panel of monoclonal antibodies (TAbs 250-265), with specificity for extracellular epitopes of gp185, an immunoradiometric assay was developed to quantitate this shed antigen. The immunoradiometric assay detected membrane-bound and soluble gp185 as well as a soluble derivative corresponding in sequence to the extracellular domain of gp185 (designated gp75). This recombinantly expressed gp75 was immunoaffinity purified and used to generate a standard curve from which serum samples were quantitated. Increases in antigen levels measured in the sera of tumor-bearing nude mice correlated with both overexpression of the c-erbB-2 protein and increased tumor volume. Positive sera were obtained from mice given implants of NIH3T3 cells transfected with c-erbB-2 complementary DNA (NIH3T3t), or ovarian (SK-OV-3) or breast (MDA-MB-361) tumor cell lines overexpressing the c-erbB-2 protein. In mice bearing NIH3T3t tumors, increases in tumor volume from 80 to 9000 mm3 resulted in levels of shed antigen from 8 to greater than 1000 ng/ml gp75 equivalents. Sera from mice with c-erbB-2-negative tumors or tumors overexpressing the epidermal growth factor receptor were negative in the assay. This assay, and the quantitation of shed antigen levels, may have diagnostic or monitoring utility in cancers, such as breast and ovarian, in which the c-erbB-2 protein is overexpressed.

The presence of oestrogen-alpha receptor (ER), progesterone receptor (PR), and HER-2/neu (c-erbB-2) oncoprotein in the uterine walls of 10 healthy cats and 20 subjects with cystic endometrial hyperplasia-pyometra (CEH-P) were evaluated. Lesions were graded according to the severity of cystic dilation, hyperplasia and inflammation, and were classified as normal, mild uterine hyperplasia and severe uterine hyperplasia. The ER, PR and c-erbB-2 expression in the endometrium, glandular epithelium, stromal fibroblasts and myometrial smooth muscle cells was quantified by immunohistochemistry. The ER, PR and c-erbB-2 staining patterns differed between normal uteri and uteri with CEH-P. The ER expression was tended to be higher in the endometrial surface and glandular epithelium in the severe hyperplasia group (P > 0.05) and significantly lower in the mild hyperplasia cases compared with normal endometrium (P < 0.05), whereas the PR expression in both severe and mild hyperplasia cases tended to be higher in stromal cells and glandular epithelium than those in the normal uteri. C-erbB-2 immunoreactivity was observed only in the endometrial surface and glandular epithelium of the uterine wall and immunostaining was found to be highest in cases with severe hyperplasia. As a conclusion, we suggest that c-erbB-2 oncoprotein may play a role in the pathogenesis of the CEH together with the ER and PR in cats, and that ER does not have a role in the mechanism of pyometra, whereas PR plays a role in the pathogenesis of both CEH and pyometra.

Correlations of c-erbB-2 protein expression with clinical outcomes of gastric carcinomas were studied in 189 gastric carcinomas. There were 23 (12.2%) carcinomas with evidence of c-erbB-2 protein in which the reaction was localized to the cell membrane. There was no significant association between c-erbB-2 staining and the macroscopic or histologic type of the carcinomas. c-erbB-2-stained tumors were more likely to be associated with serosal invasion, nodal involvement, and peritoneal metastasis, than c-erbB-2-unstained ones. In addition, c-erbB-2 was stained in none of early gastric carcinomas. The 5-year survival rates of the c-erbB-2 protein-positive and the protein-negative group were 11% and 50%, respectively. When the c-erbB-2 tissue status and seven clinicopathologic variables as conventional prognostic factors were entered simultaneously into the Cox regression model, serosal invasion, hepatic metastasis, peritoneal metastasis, nodal status, and c-erbB-2 tissue status emerged as independent prognostic variables. The results suggested that c-erbB-2 protein expression might be enhanced in advanced stages during the progression of gastric carcinoma. In this particular group of patients, immunoreactivity for c-erbB-2 protein is an indicator of poor short-term prognosis.

Amplified expression of p185HER-2, the protein product of the HER-2/neu proto-oncogene, appears to be involved in carcinogenesis of human mammary epithelial cells. Our data suggest that an extracellular 130 Kda glycoprotein released from breast carcinoma cells may be related to the ectodomain of p185HER-2: (1) Both cellular p185HER-2 and extracellular p130, when reduced and alkylated, reacted with antipeptide antibody against the N-terminus of the HER-2 protein [alpha N(HER-21)] and reactivity was blocked by cognate peptide; (2) Neither p130 nor other extracellular proteins reacted with antiserum against the C-terminus of p185HER-2 [alpha C(HER-2)]; (3) Partial proteolysis of p185HER-2 generated an immunoreactive fragment of 130 kDa that was similar to extracellular p130; (4) Both p130 and p185HER-2 contained carbohydrate that bound to Con-A Sepharose; (5) The amount of p130 released from breast cells corresponded to the levels of expression of cellular p185HER-2. Release of the ectodomain of p185HER-2 from breast carcinoma cells may be involved in their malignant growth and may be a useful marker for assessing the expression of p185HER-2 in human tumors.

Her-2/neu protein product was immunocytochemically analyzed in 139 breast cancers. Epidermal growth factor receptors were similarly analyzed in 74 breast cancers from the same patient pool. These results were also separated on the basis of estrogen receptor proteins and of combined aneuploidy with elevated S-phase from flow cytometry. Invasive breast cancer yielded a positive label for Her-2/neu protein (26%) and for epidermal growth factor receptor (25%), with no significant difference. Correlations with estrogen receptor labeling yielded differences significant inversely for both Her-2/neu protein (p less than 0.02) and epidermal growth factor receptor (p less than 0.01). Positive Her-2/neu protein labels correlated with a positive combination of aneuploidy and elevated S-phase (37%) and a negative combination of aneuploidy and elevated S-phase (21%), with a statistically nonsignificant difference. Positive epidermal growth factor receptor cases with aneuploidy and an elevated S-phase (75%) and without aneuploidy and elevated S-phase (42%) did differ with significance at p less than 0.05. There were eight cases positive for both Her-2/neu protein and epidermal growth factor receptor, four of six cases with negative estrogen receptor, four of six cases with negative estrogen receptor, six of six cases aneuploid, and five of six cases with an elevated S-phase. ALL eight cases had threatening disease--either stage III or stage IV, with one case of extensive ductal carcinoma in situ (comedo). Correlation of negative Her-2/neu protein with negative epidermal growth factor receptor was significant (p less than 0.05) in 74 cases. However, positive Her-2/neu protein did not correlate with positive epidermal growth factor receptor; there was a trend toward inverse correlation. We conclude that epidermal growth factor receptor labeling results show similarities to Her-2/neu protein results, but epidermal growth factor receptor tended to correlate with unfavorable ploidy and S-phase. Epidermal growth factor receptor labeling might be useful in breast cancers with macrocysts reported to show high epidermal growth factor activity.

The c-erbB-2 oncogene, is a member of tyrosine kinase oncogene family and expected to play a role in the regulation of cell growth. In the present study, prognostic significance of the expression of c-erbB-2 oncoprotein was investigated by immunocytochemical assay with 130 primary breast cancer patients. The positive expression of c-erbB-2 oncoprotein was found in 53 out of 130 patients (40.8%). There was no significant correlation between expression of c-erbB-2 oncoprotein and conventional prognostic factors, estrogen receptor (ER), axillary lymph node metastasis and epidermal growth factor receptor (EGFR). Relapse free survival rate of the patients with positive c-erbB-2 expression was significantly worse than those with negative at 49 month after operation. Similar result was found in overall survival rate but the difference was not significant. Furthermore, when patients were stratified by regional nodal status, in the patients with lymph node metastasis, the prognosis of the patients with positive c-erbB-2 expression was significantly worse than those with negative, while no significant difference was found in the patients without lymph node metastasis. These results suggest that c-erbB-2 oncoprotein may act as a prognostic factor independently, predicting the prognosis of breast cancer patients.

AIM: Considering the roles of c-erB-2 and p53 oncoproteins in tumor progression, we aimed to evaluate their expression in hydatidiform moles, and the possible predictive value of this immunoexpression in postmolar follow-up. METHODS: Group I comprised 35 patients with progression to gestational trophoblastic tumor, and group II included 32 patients with progression to spontaneous remission. Immunohistochemical tests were performed by streptavidin-peroxidase method. c-erbB-2 immunoexpression was evaluated according to quantitative and semiquantitative criteria; p53 according to percentage of cells with stained nuclei. Data were analyzed by Student t-test, Mann-Whitney test, ROC curve and logistic regression analysis. RESULTS: c-erbB-2 and p-53 expressions were significantly increased in group I. Quantitative and semiquantitative analysis of c-erb-2 showed that its expression may be associated with mole hydatidiform progression to gestational trophoblastic tumor. Taking into account cells with complete membranous delineation we proposed a cut-off value of 10.8%. Similarly, considering the percentage of cells presenting nuclei marked by p53 we suggested a cut-off value of 40.1% for the prediction of malignant transformation of mole hydatidiform. CONCLUSIONS: c-erbB-2 and p53 immunoexpression in hydatidiform mole are usually increased with malignant transformation. In addition to beta-fraction of human chorionic gonadotropin, they could possibly help the establishment of a therapeutic protocol.

The neu/HER2 proto-oncogene encodes a transmembrane tyrosine kinase homologous to receptors for polypeptide growth factors. The oncogenic potential for the presumed receptor is released through multiple genetic mechanisms including a specific point mutation, truncation at the extracellular domain and overexpression of the protooncogene. Here we show that ALL these modes of oncogenic activation result in a constitutively phosphorylated neu protein and an increase in tyrosine phosphorylation of a phosphatidylinositol-specific phospholipase (PLC gamma). The examined transforming neu/HER2 proteins, unlike the normal gene product, also co-immunoprecipitated with PLC gamma molecules. A kinase-defective mutant of a transforming neu failed to mediate both tyrosine phosphorylation and association with PLC gamma, suggesting direct interaction of the neu kinase with PLC gamma. This possibility was examined by employing a chimeric protein composed of the extracellular ligand-binding domain of the epidermal growth factor receptor and the neu cytoplasmic portion. The chimeric receptor mediated rapid ligand-dependent modification of PLC gamma on tyrosine residues. It also physically associated, in a ligand-dependent manner, with the phosphoinositidase. Based on the presented results we suggest that the mechanism of cellular transformation by the neu/HER2 receptor involves tyrosine phosphorylation and activation of PLC gamma.

Lobular carcinoma in situ (LCIS) has uncertain malignant potential; biologic markers that will identify patients at risk for a poor clinical outcome have been sought actively. Amplification of the c-erbB-2 protooncogene has been correlated with poor prognosis in invasive mammary carcinoma, and immunohistochemical evaluation for expression of the oncogene protein has been correlated with gene amplification. The authors retrospectively evaluated 62 cases of lobular neoplasia for expression of the c-erbB-2 gene product on formalin-fixed, deparaffinized sections, using two monoclonal anti-erbB-2 (p185) antibodies (c-neu Ab3 and m-erb) and one polyclonal anti-erbB-2 antibody (pAb 1) by the avidin-biotin-peroxidase method. ALL 62 cases were negative with the pAb 1 antibody; one of 62 cases was weakly positive with the c-neu Ab3 in a membranous pattern. expression of c-erbB-2 gene product was identified on adjacent invasive ductal carcinoma in one case and in adjacent ductal carcinoma in situ in another. None of 15 cases if infiltrating lobular carcinoma was positive with either of the two anti-c-erbB-2 antibodies. Strong positivity was found on benign epithelium in one case, demonstrating epitheliosis. In summary, evidence of expression of the c-erbB-2 gene product was found in one of 57 cases of LCIS and none of 15 cases of invasive lobular carcinoma. This suggests that, in contrast to reported data concerning intraductal and invasive ductal carcinoma, c-erbB-2 oncogene amplification and/or overexpression does not play a significant role in the progression of lobular breast neoplasia.

The c-erbB-2 proto-oncogene encodes a growth factor receptor which is over-expressed in a variety of human adenocarcinomas. Recent reports suggest that it may be of value in arriving at prognosis in breast and ovarian cancer. In this study, c-erbB-2 expression was investigated in 93 routinely processed cases of gastric carcinoma, using an immunohistochemical technique. c-erbB-2 membrane immunoreactivity was observed in 11% (10/93) of tumours, ALL of which were of the well differentiated intestinal type (p less than 0.01). Overall, patients with tumours expressing this proto-oncogene had a significantly improved prognosis (p less than 0.05). Within the group of intestinal-type tumours, those that were c-erbB-2-positive formed a distinct sub-population which had a better prognosis (p less than 0.02), suggesting possible differences in aetiology.

Heavy chain gene rearrangements were analyzed in 67 independently derived reticuloendotheliosis virus (REV-T) transformed avian lymphoid cell lines. The status of the heavy chain genes in these REV-T transformed cell lines was determined, in part, by the age of the chicken whose spleen cells were transformed. Cell lines derived by the in vitro transformation of splenic lymphocytes obtained from embryos did not contain heavy chain gene Ig rearrangements. By contrast, splenic lymphocytes transformed by REV-T obtained from birds 1 week or older generally exhibited heavy chain gene rearrangements. The REV-T transformed lymphoid cell lines with heavy chain rearrangements also had light chain gene rearrangements. The Ig gene rearrangements in REV-T transformed cells were functional. The majority of the cells which had heavy chain rearrangements expressed a 2.2-kb mu transcript and synthesized and secreted IgM. An REV-T transformant was also identified which produced IgG, suggesting that v-rel can transform a terminally differentiated cell. Irrespective of their Ig chain gene status the REV-T transformed cell lines expressed variable amounts of some but not ALL normal B cell-specific markers and failed to express T cell markers. ALL the cell lines analyzed expressed the B-L (Ia-like) antigen as well as a common leukocyte antigen. Based on the expression of these surface molecules, the transformants with or without Ig gene rearrangements ALL appear to be committed to the B cell pathway.

The mutant c-erbB-2 gene encoding a protein with Glu instead of Val-659 in the transmembrane domain is able to transform NIH3T3 cells, while the wild type c-erbB-2 unless overexpressed does not. The mutant c-erbB-2 protein shows enhanced tyrosine kinase activity in vitro. Transient expression of this active c-erbB-2 stimulated the 12-O-tetradecanoylphorbol-13-acetate (TPA) response element, serum response element, and cyclic AMP response element. Particularly, stimulation of the TPA response element by active c-erbB-2 was prominent. In contrast, transient expression of wild type c-erbB-2 stimulated none of these elements. Transactivation of the TPA response element was also observed in a cell line that stably expresses active c-erbB-2. The active c-erbB-2-induced transactivation of the TPA response element was partially prevented either by down-regulation of protein kinase C or by the protein kinase C inhibitor H7. These results indicate that protein kinase C is partly involved in oncogenic signalling of the active c-erbB-2 protein that leads to Jun/Fos-mediated transcriptional activation in nuclei.

HER-2/neu oncoprotein overexpression was compared in fresh frozen and paraffin-embedded formalin-fixed invasive breast cancer material from the same patients. The HER-2/neu protein was detected by an immunohistochemical staining method, and the average amount of protein staining per cell was measured using the CAS-200 image analysis system and expressed relative to the amount of HER-2/neu protein of calibration cells of the SKBR3 cell line which are known to have amplification of the HER-2/neu gene and overexpression of the HER-2/neu protein. There was a significant correlation between degree of HER-2/neu protein overexpression and DNA-hyperdiploidy (P less than 0.01, chi 2 test). No significant correlation could be demonstrated between degree of HER-2/neu overexpression and tumor size, lymph node status, number of positive nodes or morphometric features. There was in general a good concordance (r = 0.83) in HER-2/neu expression values between fresh and paraffin-embedded material. Pairwise comparison of the two series (Wilcoxon signed ranks test) revealed no significant differences, indicating that there were no systematic differences between HER-2/neu assessments in fresh and paraffin material. When analysing the HER-2/neu expression values according to thresholds used earlier for overexpression, comparable results for fresh and paraffin material were obtained for most cases. In the fresh and paraffin material a different staining pattern was observed (more membrane staining in the fresh material in contrast to a more diffuse staining pattern in the paraffin material). It was concluded that both fresh-frozen and paraffin-embedded, formalin-fixed material is suitable for assessment of HER-2/neu protein overexpression by image analysis and provides comparable HER-2/neu expression values in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)FAU - van Diest, P J

OBJECTIVES: To investigate the usefulness of the overexpression of the human epidermal growth factor receptor (HER-2) oncoprotein in patients with bone metastatic prostate cancer as a marker for the time to recurrence and outcome after endocrine therapy. METHODS: We studied 50 patients who had been diagnosed with bone metastatic prostate cancer. HER-2 overexpression in the prostatic tissue by biopsy was evaluated by immunohistochemistry using the Hercep test. The results were scored into four levels by two pathologists; scores greater than 1+ were considered positive. RESULTS: The HER-2 staining score was 0, 1+, 2+, 3+, and indeterminate in 28, 4, 11, 6, and 1 case, respectively. HER-2 was overexpressed (greater than 1+) in 21 patients (42%). The cause-specific survival and nonrecurrence rates were significantly lower in the HER-2-positive group than in the negative group (P = 0.0084 and P = 0.0485, respectively). Furthermore, the cause-specific survival rate after recurrence was significantly greater in the HER-2-negative group than in the positive group (P = 0.0247). CONCLUSIONS: We consider that HER-2 overexpression, as measured by immunohistochemistry, may be useful as a marker of an unfavorable prognosis by predicting the interval until relapse and outcome after endocrine therapy in patients with bone metastatic prostate cancer.

The expression of neu oncoprotein was assayed by immunohistochemistry (IHC) on 245 paraffin-embedded, Stage I and II breast cancers from patients treated at the City of Hope between the years 1980 and 1987. Only cases showing membrane staining were scored as positive. Fifty-four (22%) of the tumors stained positively for neu. Probability of disease-free survival (DFS) and overall survival (OS) was compared based on neu positivity and other prognostic factors. Overall, DFS and OS did not differ significantly among neu-positive and neu-negative cases. However, when only cases with favorable (Stages I and II) nuclear grade were analyzed, OS and DFS were significantly lower in neu-positive cases, with a 9-fold increase in risk of death and a 3-fold increase in risk of relapse. Our findings suggest that immunohistologic study of neu oncoprotein may help to define patients at greater risk among low-stage/low-nuclear-grade patients with breast cancer, a group hitherto recognized as having a good prognosis.

Epidermal growth factor (EGF) and EGF-related growth factors are present in the urine, and EGF has been identified as a urinary component that enhances urinary bladder tumor formation in rats. Neu oncogene encodes a cell surface receptor similar to the EGF receptor and is known to be activated by a point mutation of DNA that encodes the transmembrane domain of the neu protein (p185). In this study, we examined the possible mutational activation of neu oncogene in 50 urinary bladder transitional cell carcinomas (TCC) induced in F344 rats by the following carcinogenesis models: (i) 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) (4 weeks)----3% uracil (20 weeks); (ii) 0.2% N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) (6 weeks)----5% sodium saccharin (72 weeks); and (iii) N-methyl-N-nitrosourea (MNU) 20 mg/kg body wt, i.p. twice per week for 4 weeks----3% uracil (20 weeks). The DNA sequence around the transmembrane domain of neu gene was amplified by PCR and sequenced. The results showed no mutation within the examined DNA sequences, indicating that neu oncogene is not activated by a point mutation in the transmembrane domain in urinary bladder carcinomas induced by BBN, FANFT or MNU.

Chromogenic in situ hybridization (CISH), which uses an enzymatic reaction to detect the hybridized DNA probe, is a new alternative to fluorescence in situ hybridization (FISH) for the assessment of HER-2 oncogene amplification status in breast cancer. The main advantage of CISH over FISH is the use of bright-field microscopy, which is rapid and allows the histopathological evaluation of tumour tissue sections. The main disadvantage of CISH has been the use of a single probe, thereby making it necessary to hybridize the control probe (chromosome 17 centromere) on an adjacent tissue section. The present paper presents an efficient protocol for dual-colour CISH (dc-CISH) based on the co-hybridization of probes to the HER-2 oncogene and chromosome 17 centromere. The probes were detected sequentially with antibodies to digoxigenin and biotin and with secondary antibody polymers labelled with horseradish peroxidase and alkaline phosphatase. The peroxidase reaction was visualized with tetramethyl benzidine (green reaction product) and the alkaline phosphatase reaction with New Fuchsin (red reaction product). The accuracy of the method was verified by comparing the results for four cell lines and 40 tumour samples with those obtained using FISH (Vysis Inc.). The results of FISH and dc-CISH showed high concordance (91%, Kappa coefficient = 0.82). It is concluded that dual-colour CISH, which is a new alternative to FISH enables the assessment of copy number ratio (HER-2/17 centromere) in conjunction with proper histopathological evaluation and the ease of bright-field microscopy.

The Nottingham prognostic index (NPI) is a widely adopted prognostic tool in breast cancer. The HER-2 oncogene overexpression is also associated with higher risk. The aim of our study is to investigate the correlation between the NPI and HER-2 in breast cancer. Two hundred and five patients with breast cancer managed in the Department of Surgery, University of Hong Kong Medical Centre, at Queen Mary Hospital between January 1995 and December 1997 were studied. This is a retrospective analysis of prospectively collected database. Variables evaluated for the analysis of prognostic significance included tumor size, axillary lymph node status, histological grade, estrogen and progesterone receptor status and HER-2 oncogene expression. NPI was calculated from tumor size, lymph node status and histological grade. In univariate analysis, tumor size, axillary lymph node status, distant metastasis status, HER-2 oncogene overexpression and NPI score were found to be significant variables. Significant poorer overall survival was also observed with higher NPI category and positive HER-2. Only tumor size and NPI category with subdivision by HER-2 status were independent factors in multivariate analysis . The combination of the HER-2 oncogene expression status with the widely adopted NPI provides a reliable way to predict prognosis in breast cancer patients.

A novel multiparameter flow-cytometric method was used to quantify the expression of epidermal growth factor receptor (EGFR) and c-erbB-2 oncoprotein on 85 cryopreserved normal tissues (30 ovary, 29 endometrium, 16 cervix) and 67 carcinomas (31 ovarian, 18 cervical, 15 endometrial, 3 vulvar). Overexpression of the EGFR and c-erbB-2 oncoproteins was found in respectively 3/31 (9%) and 10/31 (32%) ovarian carcinomas, 13/18 (72%) and 7/18 (38%) cervical carcinomas, and 2/15 (13%) and 2/15 (13%) endometrial carcinomas. oncoprotein expression was significantly higher in the malignant tumors (for ALL tumor sites) than in the corresponding normal tissues (P less than 0.034 for ALL combinations). Aneuploid tumors expressed levels of EGFR and c-erbB-2 oncoprotein significantly higher than those of DNA diploid tumors (P = 0.042 and P = 0.048, respectively). oncoprotein could be detected in nearly ALL normal tissues: expression was higher in premenopausal than in postmenopausal patients (EGFR, P = 0.07; c-erbB-2, P less than 0.001). The present study supports the idea that EGFR and c-erbB-2 may play an important role in the autocrine, paracrine, and/or endocrine growth control and differentiation of normal tissues. Alteration in the expression of these oncoproteins is probably involved in malignant transformation and tumorigenesis.

A series of 21 male breast carcinomas were immunostained using NCL-CB11, an antibody directed against the internal domain of the c-erbB-2 transmembrane oncoprotein. In contrast to female breast cancer, where up to 35% of cases show positivity, ALL of these cases were negative. This suggests that no prognostic information regarding patient survival can be made in these patients and that male breast carcinomas may be under different growth control mechanisms from female breast carcinomas.

A sandwich radioimmunometric assay using monoclonal antibodies 6G10 and SV2-61 gamma directed to the extracellular domain of the c-erbB-2 oncogene product was developed and the antigen levels in sera from normal donors and patients with breast carcinoma were determined. The antigen levels in normal donors were uniformly low (9.52 +/- 0.91 ng/ml) and 3.0% (2/66 cases) slightly exceeded the cutoff value (11.4 ng/ml). In patients with breast carcinoma, serum c-erbB-2 protein levels increased and the positivity was as high as 45.7% (16/35 cases) in recurrent cases. Determination of c-erbB-2 protein may be a useful marker for serological diagnosis of breast carcinoma.

The expression of c-erb B-2 oncoprotein was studied immunohistochemically in paraffin embedded biopsy specimens of 91 female breast carcinomas. The mean (+/- SD) age of the patients at diagnosis was 59.0 (+/- 13.2) years and they were prospectively followed-up for a mean of 12.4 years (range 11.5-13.3 years). The c-erb B-2 expression was analysed in relation to clinical stage, menopausal status, histological grade, tubular growth pattern, irregularity of nuclei, DNA ploidy and clinical outcome during the follow-up. Grade III tumours showed higher c-erb B-2 expression than low grade tumours and the c-erb B-2 expression than low grade tumours and the c-erb B-2 positivity was also related to the irregularity of the nuclei (p = 0.0815). Crude survival (p = 0.0635) and breast cancer survival (p = 0.072) could be predicted by c-erb B-2 expression, in that the c-erb B-2 negative tumours survived longer. The prediction of crude survival (p = 0.03), breast cancer survival (p = 0.04) and disease-free survival (p = 0.037) was more reliable in postmenopausal women. The results suggest that c-erb B-2 oncogene expression can be used as a prognostic parameter in predicting the biological behaviour of female breast cancer.

Incubation of Swiss 3T3 murine fibroblasts at low temperatures induces phosphorylation on tyrosine of a transmembrane protein of 175 kDa. This phenomenon is time and temperature dependent and reaches a maximum after 2 hr at 4 degrees C. The 175 kDa protein phosphorylated in vivo at low temperatures can be immunoprecipitated by phosphotyrosine antibodies and displays auto-kinase activity in vitro in the presence of radiolabelled ATP. This molecule was found to react with anti-peptide antibodies directed against the product of the HER2/neu proto-oncogene only when immunoprecipitated with phosphotyrosine antibodies from cold-stimulated cells. Activation of protein kinase-C by treatment of the cells with phorbol esters, bombesin or PDGF inhibits the effect of the exposure to low temperatures. Phosphorylation of p175 is not induced by treatment of the cells with the phosphatases inhibitor sodium orthovanadate. These results suggest that, at low temperatures, the tyrosine kinase associated with the putative receptor encoded by c-neu is activated by physico-chemical modifications of the plasma membrane.

The proto-oncogenes c-erbB-2 and epidermal growth factor (EGF) receptor which encode 2 closely homologous transmembrane glycoproteins have been found amplified and/or overexpressed in a range of epithelial malignancies. In a series of 46 head and neck squamous cell cancers (SCCs), immunohistochemical reactivity for the EGF receptor was detected in ALL cases, particularly at the invading edge of cellular islands of SCC and in the basal cells of normal adjacent squamous epithelium. Southern blot analysis demonstrated EGF receptor gene amplification in 3 cases. In contrast, strong membrane staining for the c-erbB-2 oncoprotein was not detected in any sample, and there were no cases of c-erbB-2 gene amplification. Despite a close structural and (presumed) functional homology between these 2 receptor-oncoproteins in the development of malignancy, we report that their expression in SCCs is markedly different. Furthermore, unlike the situation for breast cancer, quantitation of the c-erbB-2 or EGF receptor oncoproteins is unlikely to yield important prognostic information in this group of patients.