7157

TP53

tumor protein p53;TP53;tumor protein p53

antigen NY-CO-13|cellular tumor antigen p53|mutant tumor protein 53|p53 tumor suppressor|phosphoprotein p53|transformation-related protein 53|tumor protein 53

17p13.1

protein-coding

BACKGROUND: Determination of prognosis factors associated with survival, recurrence, progression, and development of metastasis in T1 and T2a transitional cell carcinoma (TCC) of the bladder is discussed. METHODS: A study was conducted of a group of 210 patients with primary bladder TCC at classification T1 (n = 175) and T2aN0M0 (n = 35). A total of 177 variables were studied in each patient. The monoclonal antibodies used were the following: DO7 (p53) and MIB-1 (Ki-67). Prognosis was obtained using Kaplan-Meier methodology and Cox proportional hazards model. RESULTS: The average follow-up period was 6.7 years. cancer-related survival rates at 5 and 10 years were 82.96% and 74.78%, respectively. The independent survival variables were the following: age and expression of p53. Recurrence free survival at 5 and 10 years stood at 51.80% and 42.71%, respectively. The independent recurrence variables were T2a classification, tumor multifocality, tumor size of greater than 3 cm, carcinoma in situ in random biopsy, and expression of Ki-67. Progression free survival rates at 5 and 10 years were 75.31% and 69.16%, respectively. The independent progression variables were age, T2a classification, and expression of p53. metastasis free survival rates at 5 and 10 years stood at 87.23% and 84.55%, respectively. The expression of p53 was the sole variable to provide an independent prediction of metastasis. CONCLUSIONS: The expression of p53 clearly has an independent effect on the prediction of survival, progression and development of metastasis, showing a dose-response effect. tumor multifocality and T2a classification are the variables that best predict recurrence.

Chemokine receptor CXCR4 and its ligand CXCL12 are suggested to be involved in migration, invasion and metastasis of breast cancer cells. mutation of the tumor suppressor gene p53 in breast cancer is associated with metastasis and aggressive clinical phenotype. In this report, we demonstrate that wild type but not the dominant-negative mutant (V143A) or cancer-specific mutants (R175H or R280K) of p53 repress CXCR4 expression. Recently described cancer-specific p53 isoform, Delta133p53, also failed to repress CXCR4 promoter activity. Short-interfering RNA-mediated depletion of p53 increased endogenous CXCR4 expression in MCF-7 breast cancer cells that contain wild-type p53. Basal CXCR4 promoter activity in HCT116 colon carcinoma cells deleted of p53 [HCT116(p53KO)] was 10-fold higher compared to that in parental HCT116 cells with functional wild-type p53. Deletion analysis of CXCR4 promoter identified a seven-base pair p53-repressor element homologous to cyclic AMP/AP-1 response (CRE/AP-1) element. Electrophoretic mobility shift and chromatin immunoprecipitation assays revealed binding of ATF-1 and cJun to the CRE/AP-1 element. The p53 rescue drug PRIMA-1 reduced CXCR4 mRNA and cell surface expression in MDA-MB-231 cells, which express R280K mutant p53. CP-31398, another p53 rescue drug, similarly reduced cell surface levels of CXCR4. PRIMA-1-mediated decrease in CXCR4 expression correlated with reduced invasion of MDA-MB-231 cells through matrigel. These results suggest a mechanism for elevated CXCR4 expression and metastasis of breast cancers with p53 mutations or isoform expression. We propose that p53 rescue drugs either alone or in combination with chemotherapeutic drugs may be effective in reducing CXCR4-mediated metastasis.

Second-site suppressor (SSS) mutations in p53 found by random mutagenesis have shown to restore the inactivated function of some tumor-derived p53. To screen novel SSS mutations against common mutant p53s, intragenic second-site (SS) mutations were introduced into mutant p53 cDNA in a comprehensive manner by using a p53 missense mutation library. The resulting mutant p53s with background and SS mutations were assayed for their ability to restore the p53 transactivation function in both yeast and human cell systems. We identified 12 novel SSS mutations including H178Y against a common mutation G245S. Surprisingly, the G245S phenotype is rescued when coexpressed with p53 bearing the H178Y mutation. This result indicated that there is a possibility that intragenic suppressor mutations might restore the protein function in an intermolecular manner. The intermolecular mechanism may lead to novel strategies for restoring inactivated p53 function and tumor suppression in cancer treatment.

We conducted this study to examine whether the expression of c-erbB-2 and p53 is the prognostic indicator for patients with early-stage breast cancer in which axillary lymph node metastasis is absent. We examined 326 patients with early-stage breast cancer in which axillary lymph node metastasis is absent. Tissue microarrays were constructed. Following this, immunohistochemical staining was done for estrogen receptor (ER), progesterone receptor (PR), c-erbB2, and p53. The results were as follows: (1) expression of c-erbB-2 was correlated with other clinicopathologic factors (eg, patient's age, presence of menopause, tumor size, histologic and nuclear grade, and presence of hormone receptors such as ER and PR); and (2) expression of p53 was correlated with survival rate, patient's age, presence of menopause, and tumor size. However, these results were not statistically significant. In conclusion, our results indicate that expression of c-erbB-2 and p53 did not have any prognostic value in patients with early-stage breast cancer in which axillary lymph node metastasis is absent.

In this study, we establish an MCF-7 xenograft model that mimics the progression of human breast carcinomas typified by loss of p53 integrity, development of centrosome amplification, acquired estrogen receptor (ERalpha) heterogeneity, overexpression of Mdm2 and metastatic spread from the primary tumor to distant organs. MCF-7 cells with abrogated p53 function (vMCF-7(Dnp53)) maintained nuclear ERalpha expression and normal centrosome characteristics in vitro. However, following mitogen stimulation, they developed centrosome amplification and a higher frequency of aberrant mitotic spindles. Centrosome amplification was dependent on cdk2/cyclin activity since treatment with the small molecule inhibitor SU9516 suppressed centriole reduplication. In contrast to the parental MCF-7 cells, when introduced into nude mice as xenografts, tumors derived from the vMCF-7(DNp53) cell line developed a strikingly altered phenotype characterized by increased tumor growth, higher tumor histopathology grade, centrosome amplification, loss of nuclear ERalpha expression, increased expression of Mdm-2 oncoprotein and resistance to the antiestrogen tamoxifen. Importantly, while MCF-7 xenografts did not develop distant metastases, primary tumors derived from vMCF-7(DNp53) cells gave rise to lung metastases. Taken together, these observations indicate that abrogation of p53 function and consequent deregulation of the G1/S cell cycle transition leads to centrosome amplification responsible for breast cancer progression.

Recent studies have suggested that genetic polymorphisms in the TP53 pathway influence tumour formation, progression and response to therapy. We analysed the three most common TP53 gene polymorphisms as potential genetic markers to predict the development and prognosis of breast cancer. The incidence of R72P, PIN3 Ins 16bp and PIN6 G13494A polymorphisms was determined in a cohort of 117 breast cancer tissues and 108 control specimens by PCR-RFLP. No significant difference was observed in the polymorphism variants in breast cancer specimens compared to controls. Furthermore, no statistically significant association of these polymorphisms with the outcome of the patients was observed. On the other hand we found positive correlation of lymph node metastases with both PIN3 Ins 16bp and PIN6 G13494A polymorphisms. The association of intronic TP53 variants with an aggressive breast cancer phenotype may represent a useful predictive biomarker, particularly in patients of clinical stage I with low or intermediate risk.

BACKGROUND: Brain metastasis from breast cancer is usually associated with a poor prognosis and early death. Alteration of p53 may contribute to malignant progression by abrogation of apoptosis induced by oncogene activation and by acquisition of gain-of-function properties, which promote tumour aggression. mutation in TP53 occurs at high frequency in carcinomas of the lung and gastro-intestinal tract, but is much less frequent, at 25%, in primary breast cancer. The frequency of TP53 alteration in the central nervous system (CNS) metastatic breast cancer is not known. METHODS: In all, 23 cases of histologically confirmed CNS metastatic breast cancer were identified and the coding sequence of TP53 determined. TP53 was also sequenced in two control series of primary breast carcinomas from independent clinical centres. RESULTS: We demonstrate a strikingly high frequency of TP53 mutation in the CNS metastatic lesions with an over-representation of complex mutations (non-sense/deletions/insertions). Complex mutations occur in metastatic lesions in both triple-negative breast cancer and hormone receptor/HER2-positive cases. Analysis of paired primary carcinomas and brain metastatic lesions revealed evidence for both clonal selection and generation of new mutations (missense and complex) in progression from a primary breast carcinoma to brain metastasis. CONCLUSION: mutation in TP53 is the most common genetic alteration reported during metastasis to the brain in breast cancer.

In the study, we analyzed role of p53 in predicting outcome in visceral metastasis breast cancer (VMBC) patients. 97 consecutive VMBC patients were studied. P53 positivity rate was 29.9%. In the p53-negative group, median disease free survival (DFS), and time from primary breast cancer diagnosis to death (OS1), time from metastases to death (OS2) were 25, 42.5, and 13.5 months, respectively. In the p53-positive group, they were 10, 22, and 8 months, respectively. Statistically significant differences in DFS and OS1 were detected between the p53-negative and p53-positive subtypes. However, p53 appears to have no influence on OS2. In Cox regression analysis, p53 expression and TNM stage were predictive factors of DFS. In the multivariate analysis, p53 expression and the duration of DFS correlated with OS1, but not for OS2. Taken together, our data indicate p53 showing predicting role in OS1 for VMBC, but not for OS2.

Mutant p53 (mtp53) gain of function (GOF) contributes to various aspects of tumor progression including cancer stem cell (CSC) property acquisition. A key factor of GOF is stabilization and accumulation of mtp53. However, the precise molecular mechanism of the mtp53 oncogenic activity remains unclear. Here, we show that ribophorin II (RPN2) regulates CSC properties through the stabilization of mtp53 (R280K and del126-133) in breast cancer. RPN2 stabilized mtp53 by inactivation of glycogen synthase kinase-3beta (GSK3beta) which suppresses Snail, a master regulator of epithelial to mesenchymal transition. RPN2 knockdown promoted GSK3beta-mediated suppression of heat shock proteins that are essential for mtp53 stabilization. Furthermore, our study reveals that high expression of RPN2 and concomitant accumulation of mtp53 were associated with cancer tissues in a small cohort of metastatic breast cancer patients. These findings elucidate a molecular mechanism for mtp53 stabilization and suggest that RPN2 could be a promising target for anti-CSC therapy.

HYPOTHESIS: We hypothesized that p53 mutations (mp53) are associated with decreased expression of thrombospondin 1 (TSP-1) and that decreased TSP-1 expression is associated with lymph node metastases. DESIGN: A retrospective study of lymphatic mapping and pathologic determination of angiogenesis markers in primary colorectal cancer. SETTING: Tertiary care cancer institute. PATIENTS: Sixty-one patients with colorectal cancer underwent lymphatic mapping. Lymph nodes that stained negative by hematoxylin-eosin were examined with immunohistochemistry for micrometastases. Primary tumors were analyzed by immunohistochemistry for mp53 and TSP-1 expression. The t test and the Mann-Whitney U test were used to examine the mean difference in TSP-1 expression between tumors. MAIN OUTCOME MEASURES: Mutant p53 expression, TSP-1 expression, and metastatic progression. RESULTS: Thirty-six of the 61 patients (59%) had nodal metastases shown by hematoxylin-eosin or immunohistochemistry in the sentinel node (N2, N1, N1mi, or N0[i+]). Patients with a truly negative sentinel node (pN0[i-][sn]) had significantly higher TSP-1 expression compared with those with some degree of nodal metastases (57.7 vs 30.1; P < .001). Acquisition of mp53 was associated with a decreased mean TSP-1 expression. tumors without mp53 expression had a mean TSP-1 optical density value of 51.3 while tumors with elevated mp53 had a mean TSP-1 optical density value of 31.8 (P < .03). CONCLUSIONS: Patients with primary colorectal cancer with low TSP-1 expression, with or without detection of mp53 gene product, are more likely to harbor lymph node metastasis than patients with higher expression. Patients with a truly negative sentinel node (pN0[i-][sn]) frequently have higher expression of TSP-1 that may have inhibited metastatic progression. Further studies will investigate the relationship between mp53, TSP expression, and disease progression.

Recent studies have suggested that activation of the EGFR pathway leads to malignant transformation only if the p53 protein is inactivated. Therefore, we evaluated the impact of TP53 mutations on cetuximab-based chemotherapy (CT) sensitivity in combination with KRAS mutations that have been associated with cetuximab resistance. KRAS and TP53 status were assessed in tumours from 64 metastatic colorectal cancer patients treated with cetuximab-based CT and correlated to clinical response using the Fishers exact test. Times to progression (TTPs) according to gene status were calculated using the Kaplan-Meier method and compared with log-rank test. TP53 mutations were found in 41 patients and were significantly associated with controlled disease (CD), as defined as complete response, partial response or stable disease (P=0.037) and higher TTP (20 vs 12 weeks, P=0.004). Remarkably, in the subgroup of 46 patients without KRAS mutation, but not in patients with KRAS mutation, TP53 mutations were also associated with CD (P=0.008) and higher TTP (24 vs 12 weeks, P=0.0007). This study suggests that TP53 mutations are predictive of cetuximab sensitivity, particularly in patients without KRAS mutation, and that TP53 genotyping could have a clinical interest to select patients who should benefit from cetuximab-based CT.

To investigate the expression levels of S100A4 in human colorectal carcinoma (CC) and its relationship with clinicopathological parameters and metastatic potential, 73 pathological specimens from patients with CC were examined for S100A4 expression by RT-PCR and immunohistochemistry. An increase of S100A4 mRNA was observed in 19/23 (82.6%) CC specimens, and S100A4 was up-regulated in 40/73 (54.7%) CC cases compared with non-neoplastic mucosal tissues. Upregulation of S100A4 was significantly related to invasion, nodal status, distant metastasis and p53 expression. Next, we investigated whether S100A4 could affect p53 transactivation and stability. Interestingly, it was revealed that treatment with exogenous S100A4 protein reduced transcriptional activity of p53 and abrogated the modification of calcium binding affinity of S100A4 protein. These findings suggested that S100A4 might be involved in the progression and metastasis of human CC, presumably via modulation of the wild-type p53 protein.

Beta-catenin and p53 play key roles in tumorigenesis. The relationships between these 2 signaling pathways and their contribution to colorectal cancer metastatic progression have not been completely elucidated. We analyzed 141 cases of primary sporadic colorectal cancer, 45 matched metastases, and 80 samples of normal mucosa by immunohistochemistry on paraffin-embedded specimens. The expression profiles were also related to patients clinicopathologic features and 5-year survival. In primary tumors, beta-catenin immunoreactivity was nuclear (27%), predominantly membrane/cytosolic (46.0%) or negative (27%). This latter subgroup was strongly related to microsatellite instability, in particular to MLH-1 deficiency. Remarkably, beta-catenin membrane/cytosolic expression in primary tumors was reduced in the corresponding matched metastases. p53 showed a significant increase in immunoreactivity in (66.7%), whereas it was negative in (33.3%) of tumors. When we considered the expression of both genes, the combination of negative beta-catenin and positive p53 nuclear staining (21%) was strongly related to a higher frequency of liver metastases. Such an association was significantly related to a worse prognosis than any other combination. In a multivariate analysis, beta-catenin and distant metastases were independent prognostic markers. We suggest that a combination of low beta-catenin and high p53 expression in primary colorectal cancers may be a prognostic factor in predicting the progression of the disease, the occurrence of metastasis, and a more severe outcome.

BACKGROUND/AIMS: The aim of the present study was to investigate the clinicopathological significance of p53, Ki-67, and p16 expression in patients with colorectal adenocarcinoma. METHODOLOGY: We evaluated p53, Ki-67, and p16 expression in 356 patients with primary colorectal adenocarcinoma using an immunohistochemical staining method. The relationships between these protein expressions and clinicopathological factors were statistically analyzed. RESULTS: Positive p53 staining was detected more often in typical adenocarcinoma compared to mucinous adenocarcinoma (49% versus 17%, p = 0.007) and in well or moderately differentiated adenocarcinoma compared to poorly differentiated adenocarcinoma (50% versus 32%, p = 0.030). The level of expression of p53 protein was related to lymph node metastasis (p < 0.001) and the TNM stage of the colorectal adenocarcinoma (p = 0.006). The p53 protein expression was related to an increased tendency of lymphovascular invasion (p = 0.058). However, Ki-67 and p16 expression levels were not associated with any of the clinicopathological variables. The overexpression of p53 was correlated with a higher level of Ki-67 (p = 0.001) and positive staining of p16 (p < 0.001). CONCLUSIONS: Our data suggest that overexpression of p53, which was correlated with Ki-67 and p16 expression, plays a critical role in aggressive tumor behaviors in patients with colorectal adenocarcinoma. However, further long-term followup studies are warranted to evaluate the clinical impacts of p53 in a larger group of patients.

We previously reported that the chemopreventive agent lupulone induces apoptosis through activation of the extrinsic pathway via TRAIL DR4/DR5 death receptors overcoming SW620 cell resistance to TRAIL. However, the underlying molecular mechanisms remain unknown. Since the mitogen-activated protein kinases (MAPKs), Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38 control fundamental cellular processes such as apoptosis, we determined the role of these MAPKs in lupulone-triggered apoptosis. We analyzed the effects of JNK, ERK and p38 MAPK inhibitors on lupulone-induced apoptosis by flow cytometry using specific antibodies and real-time RT-PCR. Our data showed that among the MAPKs, only p38 played a major role in lupulone-triggered apoptosis. In contrast to JNK and ERK inhibition, the specific inactivation of p38 inhibited the lupulone-triggered up-regulation of p53 and TRAIL-death receptor DR4/DR5 expression, and prevented DNA fragmentation. Lupulone treatment enhanced the expression of the anti-apoptotic Mcl-1 protein by 60% favoring the preservation of mitochondrial integrity. The inactivation of p38 initiated a 50% reduction in Mcl-1, Bcl-2 and Bax expression without changing the Mcl-1/Bax ratio suggesting that p38 was not involved in the protective effect of lupulone on mitochondria. Our data support the view that the lupulone-triggered enhanced expression of p38 plays a major role in the activation of p53 and of the TRAIL-death receptor apoptotic pathway in SW620 human colon cancer-derived metastatic cells.

There is conflicting evidence on the predictive role of KRAS status when cetuximab is added to oxaliplatin-based regimens. This study investigated the impact of KRAS, NRAS, BRAF, PI3KCA and TP53 status on outcome of elderly metastatic colorectal cancer patients enrolled in TEGAFOX-E (cetuximab, oxaliplatin and oral uracil/ftorafur--UFT) phase II study. Twenty-eight patients were enrolled and all were evaluable for safety and activity. Twenty-three specimens were analysed for KRAS, BRAF, NRAS, PI3KCA and TP53 mutational status by means of polymerase chain reaction and correlated with objective response, progression-free survival and overall survival. An evident increase of response rate was noted in KRAS/NRAS wild-type cases (70 versus 33%, P = 0.198). KRAS/NRAS wild-type status showed an independent association with a longer progression-free survival (44 versus 9 weeks, P = 0.009). Considering the combined assessment of BRAF, KRAS/NRAS and TP53, a trend towards an increase of response rate was noted in patients without mutations (83 versus 33%, P = 0.063). Moreover, patients with all wild-type genes had significantly longer progression-free survival than patients with any mutation (48 versus 10 weeks, P = 0.007). As a single biomarker, only KRAS/NRAS proteins maintained an independent value for outcome prediction. Patients with KRAS/NRAS, BRAF and TP53 wild-type tumours could derive the maximal benefits from treatment with cetuximab, oxaliplatin and UFT.

The transcription factor AP4 mediates epithelial-mesenchymal transition (EMT) in colorectal cancer but its control in this setting is not fully understood. Here, we report the definition of a double-negative feedback loop involving AP4 and miR-15a/16-1 that regulates EMT and metastatic progression. In colorectal cancer cells, AP4 was downregulated by DNA damage in a p53-dependent manner. AP4 downregulation by p53 was mediated indirectly by the tumor-suppressive microRNAs miR-15a and miR-16-1, which targeted the 3 untranslated region (3-UTR) of AP4 mRNA, induced mesenchymal-epithelial transition (MET), and inhibited colorectal cancer cell migration and invasion. The downregulation of AP4 was necessary for induction of MET and cell cycle arrest by miR-15a/16-1. In tumor xenoplants, ectopic miR-15a/16-1 suppressed formation of lung metastases. Furthermore, AP4 directly suppressed expression of miR-15a/16-1. In clinical specimens of colorectal cancer, miR-15a levels inversely correlated with AP4 protein levels shown previously to correlate with distant metastasis and poor survival. In summary, our results define a double-negative feedback loop involving miR-15a/16-1 and AP4 that stabilizes epithelial and mesenchymal states, respectively, which may determine metastatic prowess.

BACKGROUND: Evidence for TP53 mutations as biomarker in colorectal cancer (CRC) is conflicting. METHODS: We assessed TP53 mutations in 51 patients with advanced CRC enrolled into a phase II, randomised trial of first-line tegafur-uracil (UFT)/leucovorin (LV) plus irinotecan (n = 23) versus UFT/LV plus oxaliplatin (n = 28). RESULTS: Non-functional TP53 mutations were found in 35% of patients. The response rate was not significantly different according to TP53 status. Progression-free and overall survival were longer in patients with TP53 mutations compared to those with wild-type TP53 (9 vs. 6.5 months, p = 0.0504, and 39.2 vs. 19.6 months, p = 0.0055, respectively). On multivariable analysis, TP53 mutation was independently associated with a decreased risk of death (hazard ratio 0.329, 95% CI 0.159-0.679; p = 0.0026). Treatment arm did not interact with TP53 in influencing outcomes. CONCLUSION: TP53 was not predictive of benefit from first-line irinotecan- or oxaliplatin-based chemotherapy. TP53 mutations may possibly be associated with a more indolent course of CRC after the diagnosis of metastatic disease.

Immunohistochemical expression of bcl-2, p53, PR and ER in cases with endometrial carcinomas arrayed on a tissue microarray (TMA) was tested and correlated with clinicopathologic features, overall survival (OS), cancer-related survival (CRS) and disease-free survival (DFS). Seventy-seven patients with endometrial cancer were reviewed. Slides were evaluated by two pathologists blinded to patient clinical characteristics and survival data. Mean age of patients was 62.5 years (range 35-80), median follow up 60 months (range 9-120). Seventy-nine percent of patients were FIGO Stage I; 39% of the cases showed bcl-2 cytoplasmic staining and its expression was significantly correlated with low-grade tumor differentiation and age < or = 60 years. Nuclear p53 overexpression was detected in 23.4% of the cases and was significantly correlated with advanced stages (IIB-IV), non-endometrioid histology, nodal metastasis and advanced age (> 60 years). PR and ER were positive in 63.6% and 30% of the cases, respectively. Analysis of p53 overexpression and bcl-2 expression in relationship with PR and ER status showed a direct correlation between bcl-2 expression and PR positivity (p = 0.001). In a multivariate analysis FIGO staging was the only clinicopathologic parameter independently correlated with DFS. In conclusion p53 overexpression was directly associated with unfavorable clinicopathologic factors such as advanced stage, histologic subtype, advanced patient age and nodal metastasis. Bcl-2 expression was related with younger age, favorable grade and PR expression by tumor cells. Patient survival was not related to the tested biomarkers.

Loss of heterozygosity (LOH) is implicated in the initiation and progression of various human neoplasia, and is observed in both early or in advanced-stage human cancers. The current study was aimed at investigating the frequency of LOH TP53 in human endometrial carcinoma (EC) metastases. LOH was analyzed using 3 intragenic polymorphisms in 38 primary ECs and corresponding metastatic lesions. Allelic loss at intron 1 was detected in 14 out of 38 (37%) primary carcinomas and in 11 out of 38 (29%) metastatic lesions. LOH at intron 1 in primary and metastatic tumors was concomitantly noted in 8 out of 38 (21%) cases. LOH at intron 4 was seen in 46% (17 out of 37) primary ECs and in 35% (13 out of 37) metastatic lesions. LOH at intron 4 in primary tumor/metastasis was concomitantly demonstrated in 27% (10 out of 33) cases. Allelic loss at exon 4 was detected in 5 out of 33 (15%) primary ECs and in one out of 33 (3%) corresponding metastases. Coexistence of LOH TP53 in primary ECs with metastases at intron 1 and intron 4 was observed in three out of 33 (9%) cases. Correlation between allelic loss at intron 1 in primary ECs and corresponding metastases was found (R = 0.475, p = 0.003). Moreover, there was correlation between LOH at intron 1 in metastastic ECs and allelic imbalance at intron 4 in primary uterine tumors (R = 0.416, p = 0.01). There was a relationship between LOH at intron 4 in primary ECs and corresponding metastatic lesions (R = 0.457, p = 0.004). LOH TP53 at intron 4 correlated with the presence of the neoplasm in the uterine cervix (R = 0.319, p = 0.049), and with the non-endometrioid type of primary tumor (R = 0.371, p = 0.024). There was a significant correlation between exon 4 LOH and patient age (less or equal to 50 years and above this age; R = -0.375, p = 0.032). p53 overexpression was present in thirteen out of 38 (34%) cases, both in primary ECs and in metastatic lesions. Overexpression of p53 was higher in non-endometrioid ECs (three out of 5; 60%) than in endometrioid-type uterine tumors (ten out of 33; 30.3%; p = 0.315). p53 overexpression correlated with the presence of cancer in the lumen of fallopian tube(s) (R = 0.032, p = 0.046), and with allelic loss at intron 1 in primary ECs (R = 0.599, p = 0.0001). In conclusion, LOH occurs not only in primary uterine tumors but also in corresponding metastases, with the higher incidence being reported at intron 4 of the TP53. A significant link existed between LOH TP53 at intron 1 and p53 overexpression in primary ECs, but not in the corresponding metastatic lesions.

Dysregulation of cell cycle control, especially G1/S phase transition, is implicated in the pathogenesis of most human cancers, including esophageal squamous cell carcinoma (ESCC). However, the clinicopathological significance of aberrant expression of G1/S phase-related proteins in ESCC remains unclear. In the present study, cyclin D1, p21WAF1/Cip1 and p53 protein expression were examined in 148 ESCC cases using immunohistochemistry combined with tissue microarray. We then analyzed the correlations between their expression and clinicopathological parameters and found that overexpression of p53 was associated with lymph node metastasis (P=0.001). p21WAF1/Cip1 down-regulation was an independent prognostic factor by multivariate analysis (RR=0.418, P<0.001). Further more, array-CGH results revealed that cyclin D1 gene was amplified in 45.4% of ESCC patients. This study confirms that dysregulation of G1/S related genes is common in ESCC and reduced expression of p21WAF1/Cip1 protein can predict shorter overall survival time of patients with ESCC.

The aim of this study was to examine TP53 gene deletion in esophageal cancer (EC) tissues obtained from patients and to evaluate its clinical significance. Forty surgical specimens from patients with esophageal squamous cell carcinoma were examined for TP53 gene deletion using the fluorescence in situ hybridization (FISH) technique. Thirty-two male and 8 female patients were enrolled, with an average age of 56 years. TP53 gene deletion was significantly higher in poorly-differentiated EC cases compared to well-differentiated cases (P=0.028). The TP53 gene deletion rate was also significantly higher in the group with lymph node metastasis compared to the group without lymph node metastasis (P=0.0313). The TP53 gene deletion rate was shown to be correlated with the level of differentiation and lymph node metastasis in EC; it may therefore be an important molecular marker for evaluating the condition of EC in patients.

BACKGROUND & OBJECTIVE: Molecular biological studies indicated that abnormal expression of cyclooxygenase-2(COX-2), p53, proliferating cell nuclear antigen(PCNA), and nm23 correlate with the development of gastric cancer, but the relationship between abnormal expression of above gene proteins and the biological behavior of gastric cancer was not yet clear. This study was designed to investigate the relationship between expressions of COX-2, p53, PCNA, and nm23 and the clinicopathological behavior in gastric cancer. METHODS: The expressions of COX-2, p53, PCNA, and nm23 were detected by using immunohistochemical(SP) method. RESULTS: (1) The overexpression rate of COX-2 in gastric cancer was 70.4% (50/71), and the overexpression of COX-2 was correlated to tumor size, gross morphology, histological type, lymph node metastases, and clinicopathological stage of gastric cancer (P < 0.05, or P < 0.01). (2) The overexpression rates of p53 and PCNA in 71 surgically removed specimens from the patients with gastric cancer were 74.6% and 78.9%, respectively. And the expressions of p53 (86.7%) and PCNA (88.8%) in gastric cancer patients with lymph node metastasis were significantly higher than those in patients without lymph node metastasis (53.8% and 61.5%) (both, P < 0.05), respectively. Moreover, expressions of p53(52.2%) and PCNA(60.9%) in stage I + II patients were lower than those(85.4% and 87.5%) in stage III + IV (both, P < 0.05). (3) The low-expression of nm23 in gastric cancer was 71.8%, and its low-expression rate of nm23 in patients without lymph node metastasis(88.5%) and in stage I + II (91.3%) were much higher than those in the patients with lymph node metastasis (62.2%) and in stage III + IV (62.5%) (respectively, P < 0.05). (4) The differences of histological types, depth of invasion, lymph node metastasis and clinical stage were significantly different(P < 0.05 or P < 0.001), between the patients with two or more genes expression of COX-2, p53, PCNA, and nm23 and those with less one gene expression. CONCLUSION: Our results suggest that abnormal expressions of COX-2, p53, PCNA, and nm23 associate with malignant potential, lymph node metastasis and clinical stage, and they might therefore play a role in development of gastric cancer.

PURPOSE: To investigate the effects of the expression of hypoxia-inducible factor 1alpha (HIF-1alpha) and p53 on the prognosis of human gastric cancer, the clinicopathologic characteristics of the tumors and the clinical outcome were analyzed. EXPERIMENTAL DESIGN: The expressions of HIF-1alpha and p53 proteins were studied by immunohistochemistry in 216 specimens of primary gastric cancer. RESULTS: HIF-1alpha(+)/p53(+) tumors more frequently showed an undifferentiated type, an infiltrative growth appearance, and an invasive lymphatic involvement compared with HIF-1alpha(-)/p53(-) tumors. HIF-1alpha(+)/p53(+) tumors also had more lymph node metastasis compared with HIF-1alpha(-)/p53(-) tumors. When stratified for HIF-1alpha and p53 positivity, the patients who were p53-negative and HIF-1alpha-negative had the most favorable prognosis, whereas patients who were p53-positive and HIF-1alpha-positive had the worst prognosis (P=0.0018). Using a multivariate Cox regression analysis, the depth of invasion, lymph node metastasis, and HIF-1alpha positivity were all found to be independent prognostic factors in patients with gastric cancer. CONCLUSION: Thus, HIF-1alpha is considered to be a useful independent prognostic factor in gastric cancer, and the combination of a HIF-1alpha protein overexpression with nonfunctional p53 tends to indicate a dismal prognosis.

AIM: To investigate the role of FAT10 and mutant p53 in the pathogenesis, severity and prognosis of gastric cancer. METHODS: FAT10, mutant p53 mRNA and protein levels were measured by reverse transcription (RT)-PCR and immunohistochemistry in gastric cancer tissue (n = 62), tumor-adjacent tissue (n = 62) and normal gastric tissue (n = 62). Relation of FAT10 and mutant p53 expression with clinicopathological features and clinical outcomes of gastric cancer patients were analyzed. RESULTS: The FAT10, mutant p53 mRNA and protein levels were significantly higher in gastric cancer than in its adjacent and normal tissue. The FAT10 and mutant p53 levels in gastric cancer tissue were significantly correlated with lymph node metastasis and tumor, nodes, metastasis (TNM) staging. Moreover, the high FAT10 level was associated with the overall survival rate of patients. Multivariate Cox-proportional hazards model analysis showed that mRNA and protein levels of FAT10 and mutant p53, lymph node metastasis, distant metastasis and TNM stage were the independent prognostic factors for gastric cancer. CONCLUSION: FAT10 may be involved in gastric carcinogenesis, and is a potential marker for the prognosis of gastric cancer patients. FAT10 and mutant p53 may play a common role in the carcinogenesis of gastric cancer.

INTRODUCTION: Polymorphism in codon 72, exon 4 of p53 may alter apoptosis and cancer progression. PATIENTS AND METHODS: P53 Arg72Pro genotype was assessed by PCR from 84 gastric cancer patients and 185 controls. The control group was comparable in sex, race, age, smoking, and alcohol intake to the cancer group. RESULTS AND DISCUSSION: There was no difference among the frequency of the alleles or genotypes between the groups. P53 Pro/Pro was associated to a lower risk of metastatic disease (p = 0.02) but not to lymph nodes metastasis or worst prognosis. Arg/Arg or Arg/Pro genotype may be associated to metastatic disease.

BACKGROUND/AIMS: The aim of this study was to evaluate the association of genetic polymorphisms of p53, p21, and p73 genes with susceptibility to gastric carcinoma (GC), its clinicopathologic features, and prognosis. METHODOLOGY: In a case-control study including 419 controls and 389 patients with sporadic GC, single nucleotide polymorphisms (SNPs) of p53 Arg72Pro, p21 Ser31Arg, and p73 G4C14-to-A4T14 at exon 2 were genotyped. tumor tissue was immunostained with p53 and examined for mutations in exons 5 to 8 of p53 using PCR -based single strand conformational polymorphism analysis and direct sequencing. RESULTS: The SNPs of p53, p21, and p73 genes were not significantly associated with susceptibility to GC. p53 SNP (Pro/Pro) was significantly associated with increased risks for the following subgroups: invasive infiltration-type carcinoma (odds ratio [OR], 2.09; 95% CI, 1.01 to 4.34; p = 0.048), carcinoma with peritoneal dissemination (OR, 3.42; 95%CI, 1.05 to 11.08; p = 0.04), and carcinoma with distant metastasis (OR, 3.90; 95% CI, 1.14 to 13.38; p = 0.03), but not with p53 immunoreactivity or mutations when compared with wild type. With respect to prognosis, p53 SNP (Pro/Pro) was an independent marker of poor overall survival in GC with TNM IB to IV stages (hazard ratio, 2.31; 95% CI, 1.14 to 4.69; p = 0.02), especially in GC treated by chemotherapy (hazard ratio, 2.17; 95% CI, 1.06 to 4.41; p = 0.03). CONCLUSIONS: This study provides evidence supporting the association of p53 SNP Arg72Pro with GC with invasive phenotype, peritoneal dissemination, distant metastasis, chemoresistance, and poor prognosis.

To investigate the association between p53 codon 72 polymorphisms and gastric cancer risk, a meta-analysis published in 2007 was updated with new data. Relevant literature was retrieved by searching PubMed and statistical analysis conducted using Review Manager software. Twenty-eight case-control studies were included in this meta-analysis, with 6,859 cases and 9,277 controls. The pooled results for all included studies showed that patients with gastric cancer had a borderline lower frequency of the Arg/Arg phenotype (odds ratio (OR) = 0.91, 95 % CI = 0.83-1.00, p = 0.04). When stratified for race, the difference in Arg/Arg frequency was significant among Asians (OR = 0.87, 95 % CI = 0.78-0.97, p = 0.01). On stratifying the various studies we found that, among Asians: (i) patients with cardial gastric cancer had a significantly higher frequency of the Pro/Pro genotype (OR = 1.35, 95 % CI = 1.03-1.77, p = 0.04) than those with non-cardial gastric cancer; (ii) patients with advanced (stage III/IV) gastric cancer had a significantly higher frequency of Arg/Arg (OR = 1.30, 95 % CI = 1.06-1.61, p = 0.01) than those with early (stage I/II) cancer; and (iii) patients with metastasis had a significantly higher frequency of Pro/Pro (OR = 3.31, 95 % CI = 1.31-8.41) than those without metastasis. Our study suggests that, among Asians, the p53 codon 72 Arg/Arg genotype is associated with a modestly decreased risk of gastric cancer, and that this difference in genotype distribution may be associated with cancer stage, location, differentiation and metastasis.

OBJECTIVE: To evaluate the clinical significance of microvessel density (MVD) and investigate the relationship of Endoglin (CD105), VEGF and p53 protein and their significance of clinical pathology. METHOD: Pathologic paraffin-embedded tissues and clinic data of 40 patients with primary squamous cell carcinoma of larynx were studied. Serial sections were respectively stained with Endoglin (CD105), VEGF and p53 by immunohistochemistry and its expressions were investigated. Microvessel density (MVD) highlighted by Endoglin (CD105) were counted according to a standard protocol. RESULT: Endoglin (CD105) expression in tumour tissue was significantly higher than in normal mucosa (P < 0.05). The mean MVD value for Endoglin (CD105) was 14. 90 +/- 7.40. The mean CD105-MVD value of T3 and T4 tumours showed a significantly higher staining than that of T1 and T2 tumours; The mean CD105-MVD value of tumours with metastasis was also higher than that of tumours with no metastasis (P < 0.05); The expression of VEGF was observed in cytoplasm of tumour cell and its positive rate was 77.5% in laryngeal carcinoma, which was significantly correlated with TNM stage and pathological differentiation of laryngeal carcinoma (P < 0.05). The expression of p53 protein was mainly observed in nucleolus of tumour cell and its positive rate was 67.5%, which was significantly correlated with metastasis of lymph node. Positive relevance was found between CD105-MVD and VEGF (r = 0.641, P < 0.01); Positive relevance was also found between CD105-MVD and p53 (r = 0.534, P < 0.01). CONCLUSION: Endoglin (CD105) is a marker of tumour angiogenesis for its significant associated with active angiogenesis in laryngeal carcinoma. The study shows that CD105-MVD in laryngeal carcinoma is an independent indicator of predicting invasion, metastasis and recurrence, and evaluating prognosis of malignant tumours. CD105-MVD, VEGF and p53 could be important indicators to evaluate invasion, metastasis and recurrence of laryngeal carcinoma.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide with poor prognosis associated with tumor invasion and metastasis. The tumor suppressor p53 plays critical roles in tumor development, but there is increasing evidence for its involvement in tumor metastasis with the underlying mechanisms largely unexplored. METHODS: Using combinatorial analysis of a p53 binding database with HCC microarray expression profile, we identified a novel metastasis-related gene Lasp1 as a potential p53 target. RESULTS: In this study, we demonstrate that Lasp1 is indeed a bona fide p53 target by validating the functional repression effect of p53 on Lasp1 via a p53 response element. Transient transfection of wild-type p53 but not the mutant form suppressed Lasp1 in Hep3B (p53-/-) cells, while p53 siRNA up-regulated its expression in HepG2 (p53+/+) cells. p53 mutations at key residues involved in DNA binding abrogates the p53-mediated suppression of Lasp1 expression. In addition, Lasp1 regulates HCC cell growth as well as cell migration and invasion ability. CONCLUSIONS: p53 transcriptionally represses Lasp1, which is a partner protein in affecting HCC cell motility. This suggests that p53 may play a role in influencing tumor metastasis through Lasp1.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental pollutant that binds the aryl hydrocarbon receptor (AhR), a transcription factor that triggers various biological responses. In this study, we show that TCDD treatment counteracts the p53 activation (phosphorylation and acetylation) elicited by a genotoxic compound, etoposide, in the human hepatocarcinoma cell line HepG2 and we delineated the mechanisms of this interaction. Using small interfering RNA knockdown experiments, we found that the newly described metastasis marker, anterior gradient-2 (AGR2), is involved in this effect. Both AGR2 messenger RNA (mRNA) and protein levels were increased (sixfold and fourfold, respectively) by TCDD treatment, and this effect was mediated by the AhR receptor. The half-life of AGR2 mRNA was unchanged by TCDD treatment. Analysis of the promoter of the AGR2 gene revealed three putative xenobiotic-responsive elements (XREs) in the proximal 3.5-kb promoter. Transient transfection of HepG2 cells by the Gaussia luciferase reporter gene driven by various deleted and mutated fragments of the promoter indicated that only the most proximal XRE was active. Binding of the AhR to the endogenous AGR2 promoter was also triggered by TCDD treatment. These results suggest that AhR ligands such as TCDD might contribute to tumor progression by inhibiting p53 regulation (phosphorylation and acetylation) triggered by genotoxicants via the increased expression of the metastasis marker AGR2.

Melanoma cell lines and normal human melanocytes (NHM) were assayed for p53-dependent G1 checkpoint response to ionizing radiation (IR)-induced DNA damage. Sixty-six percent of melanoma cell lines displayed a defective G1 checkpoint. Checkpoint function was correlated with sensitivity to IR with checkpoint-defective lines being radio-resistant. Microarray analysis identified 316 probes whose expression was correlated with G1 checkpoint function in melanoma lines (Pmetastasis-free survival. Thus, p53 function, radio-sensitivity, and metastatic spread may be estimated in melanomas from a signature of gene expression.

A 61-year-old Japanese woman underwent a partial mastectomy for cancer of the right breast (pT1cN0M0, stage I). Eight months later, chest computed tomography revealed two small nodules in the left lower lobe (Segmentum basale laterale and Segmentum basale posterius; S9 and S10). She thereafter underwent partial pulmonary resections for both diagnostic and treatment purposes. The nodule of S10 was pathologically diagnosed to be primary lung cancer. The nodule of S9 was pathologically diagnosed to be poorly differentiated adenocarcinoma. The same pattern of the distribution of the p53 mutation was observed in the DNA samples of the S9 nodule and the treated breast cancer. We therefore finally diagnosed the S9 nodule to be metastatic pulmonary carcinoma. A mutation analysis of the p53 gene is thus considered to be a good modality for differentiating metastases from primary carcinomas of the lung.

TGFbeta ligands act as tumor suppressors in early stage tumors but are paradoxically diverted into potent prometastatic factors in advanced cancers. The molecular nature of this switch remains enigmatic. Here, we show that TGFbeta-dependent cell migration, invasion and metastasis are empowered by mutant-p53 and opposed by p63. Mechanistically, TGFbeta acts in concert with oncogenic Ras and mutant-p53 to induce the assembly of a mutant-p53/p63 protein complex in which Smads serve as essential platforms. Within this ternary complex, p63 functions are antagonized. Downstream of p63, we identified two candidate metastasis suppressor genes associated with metastasis risk in a large cohort of breast cancer patients. Thus, two common oncogenic lesions, mutant-p53 and Ras, selected in early neoplasms to promote growth and survival, also prefigure a cellular set-up with particular metastasis proclivity by TGFbeta-dependent inhibition of p63 function.

The tumour suppressor p53 is known to prevent cancer progression by inhibiting proliferation and inducing apoptosis of tumour cells. Slug, an invasion promoter, exerts its effects by repressing E-cadherin transcription. Here we show that wild-type p53 (wtp53) suppresses cancer invasion by inducing Slug degradation, whereas mutant p53 may stabilize Slug protein. In non-small-cell lung cancer (NSCLC), mutation of p53 correlates with low MDM2, high Slug and low E-cadherin expression. This expression profile is associated with poor overall survival and short metastasis-free survival in patients with NSCLC. wtp53 upregulates MDM2 and forms a wtp53-MDM2-Slug complex that facilitates MDM2-mediated Slug degradation. Downregulation of Slug by wtp53 or MDM2 enhances E-cadherin expression and represses cancer cell invasiveness. In contrast, mutant p53 inactivates Slug degradation and leads to Slug accumulation and increased cancer cell invasiveness. Our findings indicate that wtp53 and p53 mutants may differentially control cancer invasion and metastasis through the p53-MDM2-Slug pathway.

The purpose of this study was to determine whether p53 immunoreactivity in tumor-stromal fibroblasts assessed by the Allred scoring system in biopsy specimens obtained before neoadjuvant therapy and assessed in surgical specimens obtained after neoadjuvant therapy is significantly associated with nodal metastasis by invasive ductal carcinoma and with the outcome of 318 patients with invasive ductal carcinoma who received neoadjuvant therapy, according to UICC pathologic TNM stage, in multivariate analyses with well-known clinicopathologic factors. The Allred scores for p53 in tumor-stromal fibroblasts in the surgical specimens were significantly associated with the presence of nodal metastasis. The Allred scores for p53 in the tumor-stromal fibroblasts of biopsy and surgical specimens were a very important outcome predictive factor for patients who received neoadjuvant therapy, independent of UICC pathologic TNM status, but the outcome predictive power of the Allred scores for p53 in tumor-stromal fibroblasts assessed in the surgical specimens was superior to that of the Allred scores for p53 in tumor-stromal fibroblasts in the biopsy specimens. The results indicated a close association between p53 protein expression in tumor-stromal fibroblasts, especially in surgical specimens, and both the presence of nodal metastasis and the outcome of invasive ductal carcinoma patients who received neoadjuvant therapy.

p53 is a tumor suppressor protein whose function is frequently lost in cancers through missense mutations within the Tp53 gene. This results in the expression of point-mutated p53 proteins that have both lost wild-type tumor suppressor activity and show gain of functions that contribute to transformation and metastasis. Here, we show that mutant p53 expression can promote invasion, loss of directionality of migration, and metastatic behavior. These activities of p53 reflect enhanced integrin and epidermal growth factor receptor (EGFR) trafficking, which depends on Rab-coupling protein (RCP) and results in constitutive activation of EGFR/integrin signaling. We provide evidence that mutant p53 promotes cell invasion via the inhibition of TAp63, and simultaneous loss of p53 and TAp63 recapitulates the phenotype of mutant p53 in cells. These findings open the possibility that blocking alpha5/beta1-integrin and/or the EGF receptor will have therapeutic benefit in mutant p53-expressing cancers.

BACKGROUND: Gallbladder cancers have a very poor prognosis without specific molecular marker being identified. In this study we studied PUMA, c-Myb and p53 expression in benign and malignant lesions of gallbladder and analyzed their clinicopathological significance. METHOD: Immunohistochemical staining of PUMA, c-Myb and p53 protein was performed in 108 gallbladder adenocarcinomas, 46 peritumoral tissues, 15 polyps, and 35 chronic cholecystitis. RESULTS: We demonstrated that the percent of positive PUMA, c-Myb and p53 expression was significantly higher in gallbladder adenocarcinomas than in peritumoral tissues, polyps and chronic cholecystitis (p < 0.05 or 0.01). Benign gallbladder epithelium with positive PUMA, c-Myb or p53 expression showed moderately or severely atypical hyperplasia. The percent of positive PUMA, c-Myb and p53 expression was significantly higher in the cases having poorly differentiated adenocarcinoma with large tumor mass, lymph node metastasis and high invasiveness than cases with well-differentiated adenocarcinoma with small tumor mass and without metastasis and invasiveness (p < 0.05 or p < 0.01). The percent of positive PUMA, c-Myb and p53 expression was significantly higher in cases with radical resection than without resection (p < 0.05). Univariate Kaplan-Meier analysis showed that PUMA, c-Myb and p53 expression was associated with decreased overall survival (p < 0.05 or p < 0.01). Multivariate Cox regression analysis showed that PUMA, c-Myb or p53 expression was a poor-prognostic predictor in gallbladder adenocarcinoma. CONCLUSION: PUMA, c-Myb and p53 expression closely relates to the carcinogenesis, fast-progression, easy-metastasis, high-invasion, and poor-prognosis in gallbladder adenocarcinoma.

The tumor suppressor gene p53 has been implicated in the regulation of epithelial-mesenchymal transition (EMT) and tumor metastasis by regulating microRNA (miRNA) expression. Here, we report that mutant p53 exerts oncogenic functions and promotes EMT in endometrial cancer (EC) by directly binding to the promoter of miR-130b (a negative regulator of ZEB1) and inhibiting its transcription. We transduced p53 mutants into p53-null EC cells, profiled the miRNA expression by miRNA microarray and identified miR-130b as a potential target of mutant p53. Ectopic expression of p53 mutants repressed the expression of miR-130b and triggered ZEB1-dependent EMT and cancer cell invasion. Loss of an endogenous p53 mutation increased the expression of miR-130b, which resulted in reduced ZEB1 expression and attenuation of the EMT phenotype. Furthermore, re-expression of miR-130b suppressed mutant p53-induced EMT and ZEB1 expression. Importantly, the expression of miR-130 was significantly reduced in EC tissues, and patients with higher expression levels of miR-130b survived longer. These data provide a novel understanding of the roles of p53 gain-of-function mutations in accelerating tumor progression and metastasis through modulation of the miR-130b-ZEB1 axis.

BACKGROUND: mutations in the p53 gene are amongst the most frequent aberrations seen in human cancer. Our objective was to characterize the clinical characteristics associated with p53 mutation in patients with advanced cancer. METHODS: We retrospectively reviewed and analyzed the clinical features and response to standard systemic therapy of 145 patients with documented tumor p53 mutational status (mutant-type [mtp53] vs. wild-type [wtp53]) referred to the Clinical Center for Targeted Therapy. RESULTS: Sixty-six (45.5%) patients had mtp53. mutations in p53 occurred more frequently in older patients (p= 0.015) and in Caucasians (p=0.024). The incidence of liver metastases was 69.2% vs. 43%, p=0.002 in mtp53 and wtp53, respectively. PTEN loss by immunohistochemistry was found more frequently in mtp53-bearing tumors compared to wtp53 (33.3% vs. 10%, p=0.007). The best progression-free survival (PFS) on standard systemic therapy was significantly longer with bevacizumab-containing regimens as compared to non-bevacizumab containing regimen in patients with mtp53 (median 11.0 [95%

The control and processing of microRNAs (miRs) is critical in the regulation of all cellular responses. Previous studies have suggested that a reduction in the expression of certain miRs, or an overall decrease in miR processing through the partial depletion of Dicer, can promote enhanced metastatic potential. We show here that Dicer depletion can promote the invasive behavior of cells that is reflected in enhanced recycling and activation of the growth factor receptors Met and EGF receptor. These responses are also seen in response to the expression of tumor-derived mutant p53s, and we show that mutant p53 can down-regulate Dicer expression through both direct inhibition of the TAp63-mediated transcriptional activation of Dicer and a TAp63-independent control of Dicer protein expression. Our results delineate a clear relationship between mutant p53, TAp63, and Dicer that might contribute to the metastatic function of mutant p53 but, interestingly, also reveal TAp63-independent functions of mutant p53 in controlling Dicer activity.

Development of metastatic cancer is a complex series of events that includes genesis of tumor-related vascular and lymphatic systems, enhanced cellular motility, and the capacity to invade and survive at distant sites, as well as evasion of host defences. The wild-type p53 protein plays key roles in controlling these facets of tumor progression, and loss of normal p53 function can be sufficient to predispose tumor cells to gain metastatic properties. In contrast, dominant p53 mutants that have gained oncogenic functions can actively drive metastasis through a variety of mechanisms. This chapter aims to highlight these processes.

OBJECTIVE: To observe PCNA p53 gene expression and their relationship with clinicopathologic factors in primary nasopharyngeal carcinoma(NPC). METHOD: PCNA, p53 proteins were assayed with immunohistochemical technique. RESULT: The expression of p53 protein was 9.5% in chronic inflammation of nasopharyngeal epithelium(CINE), which was significantly lower than it in NPCs with 76.3% (P < 0.01). In NPCs. p53 gene expression was significantly correlated with cervical lymph node metastasis of NPCs (P < 0.01), The expression of p53 in stage II, III, lV (93.3%, 80.0% and 100% respectively) were significantly higher than that in stage I (40.0%) (P < 0.01), the expression of PCNA and p53 protein was highly correlated (P < 0.01). CONCLUSION: The expression of p53 is the useful factor in diagnosis of NPC, the overexpression of p53 is related with the stage and cervical lymph node metastasis of NPC. And PCNA PI may represent the proliferative state of NPC, all of them may play important roles in the pathogenesis of nasopharyngeal carcinoma.

The prognostic value of p53 and c-erbB-2 immunostaining and preoperative serum levels of CEA and CA125 was investigated in a prospective multicentric study including 465 consecutive non-small cell lung cancer (NSCLC) patients with resectable tumors. Four end-points were used: lung cancer death, first relapse (either locoregional or metastasis), loco-regional recurrence and metastasis development. Standard statistical survival methods (Kaplan-Meier and Cox regression) were used. The specificity of the prognostic effect across different types of tumors was also explored, as had been planned in advance. Our results showed, once again, that pathological T and N classifications continue to be the strongest predictors regarding either relapse or mortality. Three of the studied markers seemed to add further useful information, however, but in a more specific context. For example, increased CEA concentration defined a higher risk population among adenocarcinomas but not among people with squamous tumors; and p53 overexpression implied a worse prognosis mainly in patients with well differentiated tumors. The analysis of type of relapse proved to be very informative. Thus, CA125 level was associated with a worse prognosis mainly related with metastasis development. Another interesting result was the influence of smoking, which showed a clear dose-response relationship with the probability of metastasis. For future studies, we recommend the inclusion of different endpoints, namely considering the relationship of markers with the type of relapse involved in lung-cancer recurrence. They can add useful information regarding the complex nature of prognosis.

In the early stage, long-term survival with non-small cell lung carcinoma has never been ideal. The aim of this study was to compare pathologically proven N0 lymph nodes obtained during mediastinoscopy with p53 gene mutation, and to correlate these with postoperative recurrence. Thirty patients undergoing mediastinoscopy for staging of non-small cell lung carcinoma were studied prospectively. Standard cervical mediastinoscopy was performed in all cases, and the specimens were divided into two pieces for histopathological and genetic investigations. All but one of the patients were male, and the mean age was 61.2 years (range, 42-74 years). Although the histopathology was negative in all cases, p53 gene mutation was observed in 6 (20%) patients. Recurrence was detected in 3 patients who had negative histopathology but were positive for p53 mutation, and in one who had negative histopathology and no p53 mutation. Patients with pathologically N0 disease and p53 gene mutation must be carefully monitored for local recurrence or distant metastasis. Neoadjuvant and/or adjuvant therapies may be considered in this group of patients.

BACKGROUND: To obtain insight into the cancer progression and metastatic process, we evaluate p53/epidermal growth factor receptor (EGFR) somatic aberrations in non-small-cell lung cancers to compare accumulated genetic alterations between primary tumors and lymph node metastases. MATERIALS AND METHODS: A total of 56 primary lung cancers with corresponding lymph node metastases were identified to investigate somatic mutations and altered expressions of p53 and EGFR for clonality assessment. Genomic DNA was extracted from macrodissected cells of paraffin-embedded primary tumor and metastatic lymph node tissues. Overexpression and somatic mutations in exons of p53 (exons 5-8) and tyrosine kinase domain of EGFR (exons 18-21) were examined by immunohistochemical staining and DNA sequencing, respectively. RESULTS: p53 and EGFR mutation/overexpression status were different between primary tumors and lymph node metastases in 5.4/7.2% and 28.6/33.9%, respectively. In most cases, the p53 and EGFR mutations usually preceded lymph node metastasis, and these gene statuses in the primary cancer and their lymph node metastasis were concordant (92.9 and 69.6%, respectively), which further supported the hypothesis that when these p53 mutations occur before the establishment of lymph node metastasis, they subsequently persist in the metastatic nodes. The expressions of p53 and EGFR showed 7.1 and 33.9% discordance in that order. CONCLUSIONS: Our results reveal that p53 and EGFR mutations usually precede lymph node metastasis. The higher prevalence of EGFR heterogeneity existing in the primary tumor is not reflected in all lymph node metastasis and thus might have therapeutic implications when adjuvant therapy is considered.

BACKGROUND AND OBJECTIVE: Tissue inhibitor of metalloproteinase-3 (TIMP-3) can regulate tumor infiltration and metastasis through multiple channels and is likely associated with mutant-type p53 (mtp53). This study detected the expressions of TIMP-3 and mtp53 in non-small cell lung cancer (NSCLC) and lymph node metastasis using tissue microarray and evaluated their significance. METHODS: TIMP-3 and mtp53 expressions were detected in 288 cases of NSCLC (NSCLC group), 106 cases of metastatic carcinoma in lymph nodes (metastasis group), and 24 cases of benign lesions in the bronchial mucosa epithelium (control group) by immunohistochemical staining (LSAB and Elivision). RESULTS: The expression of TIMP-3 in the NSCLC and metastasis groups was lower than that in the control group (P<0.001), but the reverse was true for the expression of mtp53 (P<0.001). TIMP-3 and mtp53 expressions differed between NSCLC with (P=0.015) and without (P=0.030) lymph node metastasis. TIMP-3 expression correlated with NSCLC grade (P=0.030), whereas mtp53 expression correlated with TNM stage (P=0.016) and NSCLC histological type (P=0.004). Moreover, the expressions of TIMP-3 and mtp53 were negative in NSCLC cases (P=0.008) and correlated with patient survival (P=0.011 and P=0.003, respectively). CONCLUSIONS: Low expression of TIMP-3 and high expression of mtp53 in NSCLC can promote tumor metastasis and inhibit each other. TIMP-3 and mtp53 are promising targets for studying the metastatic mechanism of NSCLC.

Distinguishing primary ovarian cancer from metastatic colorectal cancer is often difficult by a conventional pathological examination alone. We assessed the usefulness of p53 gene mutation analysis for the differential diagnosis of ovarian adenocarcinoma. A 66-year-old woman suffered multiple organ metastases, including the liver, para-aortic lymph node, and right ovary, following an operation for advanced sigmoid colon cancer. She underwent ovarian resection after effective chemotherapy against the liver and para-aortic lymph node cancer. Histological analysis suggested primary ovarian cancer. Therefore, we applied p53 gene mutation analysis for the differential diagnosis of primary versus metastatic ovarian cancer from sigmoid colon cancer. The direct sequence of the p53 gene demonstrated the same gene mutation in codon 211 (ACT to ATT) in both the sigmoid colon and ovarian cancers. According to the International Agency for Research on cancer TP53 mutation database, this type of p53 mutation in colorectal cancer and ovarian cancer is 0.13% (5/3,693) and 0% (0/1,494), respectively. Therefore, we determined that the ovarian tumor was metastatic. Although p53 gene mutation analysis has been applied in some cases, this modality is very useful for the differential diagnosis of primary and metastatic cancer.

The aim of our study was to evaluate p53 gene/protein status and MMP-2 expression in respect to ovarian tumors progress to define the role of these markers in the metastasis of ovarian carcinomas. MMP-2 and p53 alterations were evaluated on 80 malignant, 30 benign ovarian tumors, and 62 metastatic lesions by using HRM method for mutations in p53 gene and by using RT-PCR for mRNA MMP-2 level. Our data indicate that parallel expression of MMP-2 epithelial/stromal cells and p53 may enhance cells invasion and metastasis in ovarian carcinoma.

PURPOSE: Inactivation of TP53, which occurs predominantly by missense mutations in exons 4-9, is a major genetic alteration in a subset of human cancer. In spite of growing evidence that gain-of-function (GOF) mutations of p53 also have oncogenic activity, little is known about the clinical relevance of these mutations. METHODS: The clinicopathological features of high-grade serous ovarian carcinoma (HGS-OvCa) patients with GOF p53 mutations were evaluated according to a comprehensive somatic mutation profile comprised of whole exome sequencing, mRNA expression, and protein expression profiles obtained from the cancer Genome Atlas (TCGA). RESULTS: Patients with a mutant p53 protein (mutp53) with a GOF mutation showed higher p53 mRNA and protein expression levels than patients with p53 mutation with no evidence of GOF (NE-GOF). GOF mutations were more likely to occur within mutational hotspots, and at CpG sites, and resulted in mutp53 with higher functional severity (FS) scores. Clinically, patients with GOF mutations showed a higher frequency of platinum resistance (22/58, 37.9%) than patients with NE-GOF mutations (12/56, 21.4%) (p=0.054). Furthermore, patients with GOF mutations were more likely to develop distant metastasis (36/55, 65.5%) than local recurrence (19/55, 34.5%), whereas patients with NE-GOF mutations showed a higher frequency of locoregional recurrence (26/47, 55.3%) than distant metastasis (21/47, 44.7%) (p=0.035). There were no differences in overall or progression-free survival between patients with GOF or NE-GOF mutp53. CONCLUSION: This study demonstrates that patient with GOF mutp53 is characterized by a greater likelihood of platinum treatment resistance and distant metastatic properties in HGS-OvCa.

The virtual lack of well-characterized metastatic pancreatic cancer tissues for study has limited systematic studies of the metastatic process of this deadly disease. To address this important issue, we have instituted a rapid autopsy protocol for the collection of high quality tissues from patients with metastatic pancreatic cancer, called the Gastrointestinal cancer Rapid Medical Donation Program (GICRMDP). At the time of preparation of this manuscript, 20 patients with metastatic pancreatic cancer and one patient with metastatic colon cancer have undergone a rapid autopsy in association with the GICRMDP. The average time interval achieved for these 21 patients was 8.0 hours, with more than 500 individual samples of matched high quality primary and metastatic pancreatic cancer tissues, peritoneal/pleural fluid and blood obtained so far. For the first four patients in which the autopsy was performed in <6 hours, we have successfully xenografted the primary tumor and/or two to four independent matched metastases from a variety of target organ sites, with a take rate of almost 60% for the first 26 xenografted tumors attempted. In an initial survey of KRAS2, TP53 and DPC4 genetic status in lethal metastatic pancreatic cancers, activating KRAS2 mutations were detected in 82% of cases and inactivating TP53 mutations in 55% of cases, consistent with rates of genetic alteration of these genes in early stage pancreatic cancers. However, DPC4 inactivation was found in 75% of patients analyzed, suggesting that genetic inactivation of the DPC4 tumor suppressor gene continues to be selected for with growth at the primary site and metastatic spread to other organs. The invaluable tissue resources generated by the success of the GICRMDP will provide an unparalleled resource for study of metastatic pancreatic cancer and of the metastatic process in general.

TP53 mutation occurs in 50-75% of human pancreatic ductal adenocarcinomas (PDAC) following an initiating activating mutation in the KRAS gene. These p53 mutations frequently result in expression of a stable protein, p53(R175H), rather than complete loss of protein expression. In this study we elucidate the functions of mutant p53 (Trp53(R172H)), compared to knockout p53 (Trp53(fl)), in a mouse model of PDAC. First we find that although Kras(G12D) is one of the major oncogenic drivers of PDAC, most Kras(G12D)-expressing pancreatic cells are selectively lost from the tissue, and those that remain form premalignant lesions. Loss, or mutation, of Trp53 allows retention of the Kras(G12D)-expressing cells and drives rapid progression of these premalignant lesions to PDAC. This progression is consistent with failed growth arrest and/or senescence of premalignant lesions, since a mutant of p53, p53(R172P), which can still induce p21 and cell cycle arrest, is resistant to PDAC formation. Second, we find that despite similar kinetics of primary tumor formation, mutant p53(R172H), as compared with genetic loss of p53, specifically promotes metastasis. Moreover, only mutant p53(R172H)-expressing tumor cells exhibit invasive activity in an in vitro assay. Importantly, in human PDAC, p53 accumulation significantly correlates with lymph node metastasis. In summary, by using knock-in mutations of Trp53 we have identified two critical acquired functions of a stably expressed mutant form of p53 that drive PDAC; first, an escape from Kras(G12D)-induced senescence/growth arrest and second, the promotion of metastasis.

Missense mutations in the p53 tumor suppressor inactivate its antiproliferative properties but can also promote metastasis through a gain-of-function activity. We show that sustained expression of mutant p53 is required to maintain the prometastatic phenotype of a murine model of pancreatic cancer, a highly metastatic disease that frequently displays p53 mutations. Transcriptional profiling and functional screening identified the platelet-derived growth factor receptor b (PDGFRb) as both necessary and sufficient to mediate these effects. Mutant p53 induced PDGFRb through a cell-autonomous mechanism involving inhibition of a p73/NF-Y complex that represses PDGFRb expression in p53-deficient, noninvasive cells. Blocking PDGFRb signaling by RNA interference or by small molecule inhibitors prevented pancreatic cancer cell invasion in vitro and metastasis formation in vivo. Finally, high PDGFRb expression correlates with poor disease-free survival in pancreatic, colon, and ovarian cancer patients, implicating PDGFRb as a prognostic marker and possible target for attenuating metastasis in p53 mutant tumors.

The principal problem arising from prostate cancer (PCa) is its propensity to metastasize to bone and the mechanism(s) need to be further elucidated. The tumor suppressor p53 plays an important role in regulating the epithelial-mesenchymal transition (EMT) and cancer cell stemness, which have been proposed to play critical roles in cancer metastasis. MiR-145, a direct target of p53, represses bone metastasis of PCa and is involved in regulating EMT and cancer cell stemness. However, it is unknown whether wildtype p53 (WT-p53) plays a role in regulating invasion, EMT and cancer cell stemness of PCa cells and whether miR-145 mediates the function of WT-p53. In the present study, we found that ectopic expression of WT-p53 inhibited the migration and invasion, and enhanced the adhesion of p53-null PC-3 cells derived from PCa bone metastasis. Furthermore, WT-p53 suppressed the expression of the mesenchymal markers fibronectin, vimentin, N-cadherin, ZEB2 and upregulated the expression of the epithelial marker E-cadherin in PC-3 cells. Moreover, WT-p53 also suppressed colony formation, tumor sphere formation and expression of CSC markers and stemness factors including CD44, Oct4, c-Myc and Klf4 in PC-3 cells. Importantly, WT-p53 upregulated the expression of miR-145, and the inhibitory effects of WT-p53 on migration, invasion, EMT and stemness of PC-3 cells were reversed by anti-miR-145. Together, our findings demonstrate that WT-p53 suppresses migration, invasion, EMT and stemness in PC-3 cells at least partially through modulating miR-145. These results suggest that loss of WT-p53 may promote the bone metastasis of PCa at least partially through repressing miR-145 to elevate EMT and stemness of cancer cells.

Prostate cancer is a lethal cancer for the invasion and metastasis in its earlier period. P53 is a tumor suppressor gene which plays a critical role on safeguarding the integrity of genome. However, loss of P53 facilitates or inhibits the invasion and metastasis of tumor is still suspended. In this study, we are going to explain whether loss of P53 affect the invasion and metastasis of prostate cancer cells. To explore whether loss of P53 influences the invasion and metastasis ability of prostate cancer cells, we first compared the invasion ability of si-P53 treated cells and control cells by wound healing, transwell assay, and adhesion assay. We next tested the activity of MMP-2, MMP-9, and MMP-14 by western blot and gelatin zymography. Moreover, we employed WB and IF to identify the EMT containing E-cad, N-cad, vimentin, etc. We also examined the expression of cortactin, cytoskeleton, and paxillin by immunofluorescence, and tested the expression of ERK and JNK by WB. Finally, we applied WB to detect the expression of FAK, Src, and the phosphorylation of them to elucidate the mechanism of si-P53 influencing invasion and metastasis. According to the inhibition rate of si-P53, we choose the optimized volume of si-P53. With the volume, we compare the invasion and metastasis ability of Du145 and si-P53 treated cells. We find si-P53 promotes the invasion and metastasis in prostate cancer cells, increases the expression and activity of MMP-2/9 and MMP-14. Also, si-P53 promotes EMT and cytoskeleton rearrangement. Further analyses explain that this effect is associated with FAK-Src signaling pathway. Loss of P53 promotes the invasion and metastasis ability of prostate cancer cells and the mechanism is correlated with FAK-Src signaling pathway. P53 is involved in the context of invasion and metastasis.

PURPOSE: The purpose of this study was to detect mutation of the p53 gene, to assess its relationship with p53 or p21(WAF1/CIP1) expression, and to evaluate the correlation between p53 mutation or p21(WAF1/CIP1) expression and clinicopathologic findings in sebaceous carcinoma of the eyelid. METHODS: Fifteen conventional paraffin-embedded samples of sebaceous carcinoma of the eyelid were analyzed. Using the single-strand conformation polymorphism technique, the authors sequenced coding exons 5-8 of the p53 gene. The expression of p53 and p21(WAF1/CIP1) protein was analyzed by immunohistochemistry. RESULTS: In 10 of the 15 cases (66.7%), point mutations were detected in the p53 gene. CC to TT double-base changes (tandem mutations), which are known to be induced only by UV, were not detected in any of the mutations. Correlations between p53 mutation and expression were found to be statistically significant (P = 0.007). There was no significant correlation between p53 mutation and clinicopathologic findings or p21(WAF1/CIP1) expression. However, there was a significant inverse correlation between p21(WAF1/CIP1) expression and presence of lymph node metastasis (P = 0.007). CONCLUSIONS: Among human cancers, sebaceous carcinoma of the eyelid may be one of those showing most frequent mutation of the p53 gene, which may not be caused by exposure to UV. p21(WAF1/CIP1) downregulation may be associated with lymph node metastasis.

Human soft tissue sarcoma (STS) is a highly lethal malignancy in which control of metastasis determines survival. Little is known about the molecular determinants of STS dissemination. Here, we show that human STS express high levels of matrix metalloproteinase-9 (MMP-9) and that MMP-9 expression levels correlate with sequence analysis-defined p53 mutational status. Reintroduction of wild-type p53 (wtp53) into mutant p53 STS cell lines decreased MMP-9 mRNA and protein levels, decreased zymography-assessed MMP-9 proteolytic activity, and decreased tumor cell invasiveness. Reintroduction of wtp53 into STS xenografts decreased tumor growth and MMP-9 protein expression. Luciferase reporter studies showed that reintroduction of wtp53 into mutant p53 STS cells decreased MMP-9 promoter activity. Deletion constructs of the MMP-9 promoter identified a region containing a p53-responsive element that lacked a p53 consensus binding site but did contain a nuclear factor-kappaB (NF-kappaB) site. Mutating this NF-kappaB binding site eliminated the wtp53-repressive effect. Electrophoretic mobility shift assays confirmed decreased NF-kappaB binding in STS cells in the presence of wtp53. Our findings suggest a role for MMP-9 in STS progression and expand the role of p53 in molecular control of STS growth and metastasis. Therapeutic interventions in human STS targeting MMP-9 activity directly or via reintroduction of wtp53 merit further investigation.

BACKGROUND: Lymph node metastasis is the mayor cause of mortality in patients with head and neck squamous cell carcinomas (45%). The genetic changes underlying metastasis are still largely unknown and genetic markers to predict lymph node positivity still need to be found. The aim of this study was to search such markers by using Multiplex Ligation-dependent Probe Amplification (MLPA), a semi-quantitative PCR technique to detect gene copy number alterations. METHODS: Thirty-seven genes were analysed by MLPA in 34 larynx and 22 pharynx carcinomas. RESULTS: Losses of CDKN2A (9p21) and MLH1 (3p22) and gains of CCND1, EMS1 (both at 11q13), RECQL4 and PTP4A3 (both at 8q24) were the most frequent aberrations in both larynx and pharynx carcinomas. Amplifications were detected at EMS1, CCND1 and ERBB2 (17q21). A correlation between loss of N33 (8p22) and poor survival was found (p=0.02). Gain of EMS1 had the same relation with survival but not significant (p=0.08). Lymph node positive tumors presented a specific pattern of genetic alterations, with losses of N33, STK11 (19p13) and TP53 (17p13), the latter especially in larynx tumors. CONCLUSION: We propose that these 3 genes might play a role in the development of metastasis in larynx and pharynx squamous cell carcinomas.