3576

CXCL8

chemokine (C-X-C motif) ligand 8;CXCL8;chemokine (C-X-C motif) ligand 8

T-cell chemotactic factor|alveolar macrophage chemotactic factor I|beta endothelial cell-derived neutrophil activating peptide|beta-thromboglobulin-like protein|emoctakin|granulocyte chemotactic protein 1|interleukin 8|interleukin-8|lung giant cell carcin

4q13-q21

protein-coding

PURPOSE: Interleukin (IL)-8 is an important mediator of angiogenesis, tumorigenicity, and metastasis in transitional cell carcinoma (TCC) of the bladder. Nuclear factor kappaB (NF-kappaB)/relA regulates IL-8 expression in several neoplasms. The purpose of this study was to determine whether the organ microenvironment (hypoxia, acidosis) regulates the expression of IL-8 in TCC via NF-kappaB, and whether inhibition of NF-kappaB function by mutant IkappaB-alpha prevents induction of IL-8 expression. EXPERIMENTAL DESIGN: IL-8 mRNA expression and protein production by human TCC cell lines (UM-UC-14, HTB-9, RT-4, KU-7 and 253J B-V) were measured by Northern blot analysis and ELISA under acidic (pH 7.35-6.0) and hypoxic (1.0% O(2)) conditions. The involvement of NF-kappaB and activator protein 1 in the regulation of IL-8 production was evaluated by electrophoretic mobility shift assay. Furthermore, the tumorigenicity and metastatic potential of UM-UC-14 cells were determined after transfection with mutant IkappaB-alpha. RESULTS: We found that acidic and hypoxic conditions increased IL-8 mRNA expression and protein production by several, but not all, TCC cell lines evaluated. NF-kappaB, but not activator protein 1, was inducibly activated in UM-UC-14 under both acidic and hypoxic conditions, but not in UM-UC-14 mutant IkappaB-alpha transfectants. tumor growth and lymph node metastasis were inhibited in UM-UC-14 mutant IkappaB-alpha transfectants compared with UM-UC-14 controls. This effect was associated with the inhibition of IL-8 production, cellular proliferation, and angiogenesis. CONCLUSIONS: These results suggest that TCCs of the bladder have heterogenic responses to physicochemical changes in the microenvironment and identify NF-kappaB as a potential molecular target for therapy.

Previously, we have shown that a strong correlation exists between the metastatic potential of breast carcinoma cell lines and their ectopic expression of IL-8. The undifferentiated, highly metastatic cell lines with high metastatic potential produce much more IL-8 than their differentiated lower metastatic counterparts. After eliminating the possibility that transcription factor activity was responsible for differences in IL-8 release, we examined the IL-8 gene for possible epigenetic modifications. Here, we report an aberrant methylation pattern that may be responsible for the differences in IL-8 release between the high and low metastatic cell lines. We determined that none of the deoxycytidylate-phosphate-deoxyguanylate (CpG) sites in the reported IL-8 promoter were methylated in either cell type. Much further upstream in the IL-8 gene, two CpG sites were identified that are differentially methylated. These two sites were fully methylated in the high metastatic cell lines, which produce large quantities of IL-8 and remain unmethylated in the low metastatic cell lines where the IL-8 gene is relatively silent. The DNA methylation results presented here differ from the common epigenetic paradigm in which methylation of promoter CpG islands silences gene expression, suggesting that there are additional epigenetic control mechanisms that as yet have not been fully appreciated or explored.

BACKGROUND: Estrogen receptor (ER) is a very important biomarker of breast cancer. ER deletion has been consistently associated with tumor progression, recurrence, metastasis and poor prognosis, but the biological mechanism is still unclear. ER negative breast cancer expresses high levels of interleukin-8 (IL-8). ER expression can downregulate IL-8 promotor activity. As a multifunctional cytokine, IL-8 has many important biological activities in tumor genesis and development. With the goal of investigating the role of IL-8 in ER-negative breast cancer progression, we applied RNA interference technology to specifically knockdown the IL-8 expression in ER-negative breast cancer cell line MDA-MB-231. METHODS: Interfering pRNA-IL-8 and the control was transfected into ER (-) MDA-MB-231. The proliferation, cell apotosis, and invasive ability were recorded in transfected, untransfected and negative transfected cells. These cells were injected into nude mice to assess tumorigenicity, proliferation, metastasis and microvessel density (MVD). RESULTS: In vitro, decreased expression of IL-8 was associated with reduced cell invasion (P < 0.001), but had no effect on cell proliferation (P > 0.05). In vivo, neutrophils infiltration was significantly inhibited in pRNA-IL-8 transfected cells compared with untransfected and negatively transfected cells (P = 0.001, P < 0.001). Less metastasis was found in transfected cells compared with negatively transfected cells (0% vs 80%, P = 0.048). Nevertheless, we observed less MVD in transfected cells compared with control in nude mice (P < 0.001). CONCLUSIONS: IL-8 inhibits ER-negative breast cancer cell growth and promotes its metastasis in vivo, which may be correlated with neutrophils infiltration induced by IL-8.

Oncogene-mediated signaling to the host environment induces a subset of cytokines and chemokines. The Drosophila Dac gene promotes migration of the morphogenetic furrow during eye development. expression of the cell-fate determination factor Dachshund (DACH1) was lost in poor prognosis invasive breast cancer. Mouse embryo fibroblasts derived from Dach1(-/-) mice demonstrated endogenous Dach1 constitutively represses cellular migration. DACH1 inhibited cellular migration and invasion of oncogene (Ras, Myc, ErbB2, c-Raf)-transformed human breast epithelial cells. An unbiased proteomic analysis identified and immunoneutralizing antibody and reconstitution experiments demonstrated IL-8 is a critical target of DACH1 mediating breast cancer cellular migration and metastasis in vivo. DACH1 bound the endogenous IL-8 promoter in ChIP assays and repressed the IL-8 promoter through the AP-1 and NF-kappaB binding sites. Collectively, our data identify a pathway by which an endogenous cell-fate determination factor blocks oncogene-dependent tumor metastasis via a key heterotypic mediator.

Previous studies indicated that interleukins may stimulate cancer cells growth and contribute to loco regional relapse as well as metastasis. The aim in this study was to investigate the level of interleukin-6 (IL-6) and interleukin-8 (IL-8) in metastatic breast cancer patients and find out the relation between the levels of these cytokines and the clinical out come of patients and to predict the value of these cytokines as independent prognostic factors. The present study was carried out on 40 women divided into two groups; the first group included 30 patients diagnosed as having metastatic breast cancer. The second group included 10 healthy women as controls. An immunoenzymometric assays for the quantitative measurement of human IL-6 and IL-8 were used. The serum level of IL-6 and IL-8 were measured for patients and controls. Serum level of both IL-6 and IL-8 were found to be higher in patients than in healthy volunteers. Serum IL-6 was detected in all patients and controls with a mean value of (25.3 pg/ml) versus (1.5 pg/ml) for patients and controls respectively and this difference was statistically highly significant (P < 0.001). Serum IL-8 was detected in 26 patients (86.7%) and 7 controls (70%) with a mean value of (8.96 pg/ml) versus (3.9 pg/ml) for patients and controls respectively and this difference was also statistically highly significant (P < 0.001). tumors with size larger than 5 cm at diagnosis were associated with higher level of both IL-6 (32.8 pg/ml) and IL-8 (10.2 pg/ml) in comparison with those with size less than 5cm (IL-6 14 pg/ml) and (IL-8 7.2 pg/ml) and the difference in both cases was statistically significant (P < 0.05). Patients with more than 3 positive lymph nodes had higher level of both IL-6 and IL-8 with a mean value of 32.8 pg/ml and 10.2 pg/ml for IL-6 and IL-8 respectively, than those with less than 3 positive lymph nodes with mean value of 14 pg/ml and 6.9 pg/ml for IL-6 and IL-8 respectively and this difference was statistically significant (P < 0.05). Seventeen of the patients had only one metastatic site (bone or liver or lung metastasis) and 13 had more than one metastatic site and the difference between the two groups was statistically highly significant regarding both IL-6 and IL-8 (P < 0.001). The mean level of IL-6 was 14.6 pg/ml for patients with one metastatic site versus 29.2 pg/ml for patients with more than one metastatic site. The mean level of IL-8 was 6.2 pg/ml versus 11.3 pg/ml for patients with one metastatic site and patients with more than one metastatic site respectively. However, the level of IL-6 and IL-8 did not correlate with hormonal receptors status, tumour grade, menopausal status or site of metastasis. Thus, it could be concluded that serum level of IL-6 and IL-8 are useful prognostic factors in metastatic breast cancer patients.

The IL-8 and MMP-7 genes participate in the carcinogenesis of many malignancies, but the role of both genes in cervical cancer is not fully elucidated. The aim of this study was to determine the frequency of IL-8 and MMP-7 gene mutations and to assess their effects on the risk of early stage cervical cancer and lymph node metastasis. The clinical stage and histological grade of cervical cancer were also studied. The peripheral blood from the patients with early stage cervical cancers and normal controls was collected and the DNA was extracted. The incidence of IL-8 and MMP-7 gene mutations was assessed by using tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) and restriction fragment length polymorphism (RFLP). The data were statistically analyzed by x2 test. The results showed that: (1) The genotype frequency of IL-8 -251AT and TT was significantly higher in the cervical cancer group than in the normal control group (OR=2.290 and 2.619 respectively, P=0.001), and it was also higher in the lymphatic metastasis group than that without metastasis (OR=2.917, P=0.035); (2) The frequency of MMP-7 -181G/G genotype was significantly higher in the cervical cancer group and in the lymphatic metastasis group (P<0.05); (3) The incidence of IL-8 mutation was two times higher in IIa cervical cancer group than in Ib1 and Ib2 cervical cancer group (P=0.006). For the MMP-7 gene, there was statistically significant difference in the incidence of mutation between the Ib1, Ib2 and the IIa (P=0.000); (4) Different histological types and different grades of cervical cancer had different incidence of mutations, statistically. It was suggested that there was significant difference in the genotype of IL-8 -251TT and MMP-7 -181GG polymorphism between the cervical cancer group and the lymph node metastasis group. Moreover, individuals with IL-8 T allele or MMP-7 G allele carriers were at significantly higher risk of cervical cancer, particularly the early (IIa) and medium, poorly differentiated cervical cancer (G2+G3).

The aim of this study was to investigate the relationship of Interleukin-8 (IL-8) with vascular endothelial growth factor (VEGF) and plasminogen activator system (PA system) in the progression of colorectal cancer (CRC). In eighty-seven patients with CRC, the levels of IL-8, and VEGF as representative angiogenic factors and urokinase-type plasminogen activator (uPA), uPA receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), and PAI-2 as representative invasive factors were quantitatively assayed in tumor and adjacent normal tissues. The levels of IL-8, VEGF, and PA system factors in tumor tissues were all significantly higher than those in normal tissues. The IL-8 level was significantly associated with tumor size, depth of infiltration, Dukes stage, and liver metastasis, and also significantly correlated with the levels of VEGF, uPAR, uPA, and PAI-1. The VEGF level was significantly associated with tumor size, vascular involvement. The levels of uPAR and PAI-1 were significantly associated with tumor size and depth of infiltration, and the uPAR level was associated with liver metastasis. The VEGF level was significantly correlated with the levels of uPAR and PAI-1. These results reveal that IL-8, VEGF, and PA system factors are contributed to tumor growth, invasion, and metastasis in CRC. Univariate analysis revealed that high levels of IL-8, VEGF, and uPAR were significantly associated with a shorter overall survival time; however, multivariate analysis identified only liver metastasis as an independent prognostic factor. In conclusion, IL-8 is responsible to tumor progression and liver metastasis of CRC, and the activation of PAS induced by IL-8 as well as VEGF may play an important role in the progression of CRC.

Interleukin-8 (IL-8), a chemokine with a defining CXC amino acid motif, is known to possess tumorigenic and proangiogenic properties. Overexpression of IL-8 has been detected in many human tumors, including colorectal cancer (CRC), and is associated with poor prognosis. The goal of our study was to determine the role of IL-8 overexpression in CRC cells in vitro and in vivo. We stably transfected the IL-8 cDNA into two human colon cancer cell lines, HCT116 and Caco2, and selected IL-8-secreting transfectants. Real-time RT-PCR confirmed that IL-8 mRNA was overexpressed in IL-8 transfectants with 45- to 85-fold higher than parental cells. The IL-8-transfected clones secreted 19- to 28-fold more IL-8 protein than control and parental cells as detected by ELISA. The IL-8 transfectants demonstrated increased cellular proliferation, cell migration and invasion based on functional assays. Growth inhibition studies showed that IL-8 overexpression lead to a significant resistance to oxaliplatin (p < 0.0001). Inhibition of IL-8 overexpression with small interfering RNA reversed the observed increases in tumorigenic functions and oxaliplatin resistance, suggesting that IL-8 not only provides a proliferative advantage but also promotes the metastatic potential of colon cancer cells. Using a tumor xenograft model, IL-8-expressing cells formed significantly larger tumors than the control cells with increased microvessel density. Together, these findings indicate that overexpression of IL-8 promotes tumor growth, metastasis, chemoresistance and angiogenesis, implying IL-8 to be an important therapeutic target in CRC.

BACKGROUND: Interleukin-8 (IL-8) also referred to as CXCL8, a member of the CXC chemokine family that attracts neutrophils and other leukocytes, has been associated with cancer. Angiogenesis is a prime regulator of tumour expansion and data support that IL-8 is a potent angiogenic factor. Epigenomic instability has been postulated to play a role for the development of multiple neoplasias including colorectal cancer (CRC). DNA methylation of cytosine residues in CpG dinucleotides leads to transcriptional silencing of associated genes. METHOD: In this study, we comparatively analysed the protein expression of IL-8 in plasma, tumour and paired normal tissue and methylation status of the IL-8 gene to evaluate its impact on CRC. RESULTS: Collectively, by using Luminex technology, we noted a significantly higher IL-8 level in cancer tissue compared to paired normal tissue and that CRC patients exhibit significantly higher plasma levels than healthy controls. Analysed by methylation-specific polymerase chain reaction, we detected IL-8 hypomethylation in 64% of the cancerous tissue cases but no hypomethylation was found in paired normal tissue. We noted that the CRC patients with IL-8 hypomethylation revealed a significant higher level of IL-8 protein in cancerous tissue, which tended to be associated with distant metastasis. We also observed that patients with distant metastasis showed a significantly higher plasma level of IL-8 in relation to patients without distant metastasis. CONCLUSION: Our results suggest that the predominance of high plasma levels of IL-8 in patients with distant metastasis in combination with the hypomethylation of the IL-8 promoter region might be a useful marker of the disease advancement.

Liver metastases represent the major cause of death in patients with colorectal cancer (CRC). Recent studies have suggested that the chemotactic responses of tumor cells are necessary for metastatic spread to the liver, and CCL20 and CXCL8 have a strong association with CRC metastasis. The aim of our study was to identify the mechanisms by which CCL20 and CXCL8 synergize to promote metastatic progression and evaluated their potential as prognostic markers for CRC patients. The abilities of CCL20 and CXCL8 to promote CRC cell progression and epithelial-mesenchymal transition(EMT)phenotype were analyzed in vitro. Possible signaling pathways were investigated with specific pathway inhibitors and small interfering RNA (siRNA). 213 Patients with CRC who underwent surgery were enrolled for analysis of CCL20, CXCL8 and E-cadherin expressions in tumor tissues. Prognostic factors were then identified. CCL20 or CXCL8 alone was not sufficient to induce complete EMT in CRC cells, but both of them could coordinately induce EMT-like phenotype that was required to maintain CRC cell proliferation, migration and invasion. PI3K/AKT-ERK1/2 pathway crosstalk was demonstrated to be responsible for this process. Coexpression of CCL20 and CXCL8 was negatively correlated with E-cadherin expression in human CRC tissues. CRC patients with coexpression of CCL20 and CXCL8 were more likely to develop liver metastases and both coexpression was an independent high-risk factor for a most poor prognosis. CCL20 and CXCL8 synergize to promote CRC metastatic progression by coordinated induction of EMT via PI3K/AKT-ERK1/2 signaling axis. Detection of both coexpressions can be used to predict clinical outcomes in CRC patients.

Both vascular endothelial growth factor (VEGF) and interleukin 8 (IL-8) play an important role in the progression of gastric cancer (GC). In this study, we investigated whether circulating levels of VEGF or IL-8 in drainage veins of GC patients were correlated with any clinicopathological factors. Thirty-seven patients with primary GC who underwent gastrectomy at our department between 1999 and 2002 were analyzed. Blood samples were drawn from a peripheral vein just before surgery and from a drainage vein immediately after laparotomy. Plasma VEGF levels were significantly higher than those in 10 healthy controls. There was no correlation between VEGF levels in drainage veins and any clinicopathological variable, whereas there was a significant relationship in the case of VEGF levels in peripheral veins; the levels were higher in patients with venous invasion. We found a significant relationship between IL-8 levels in drainage veins and both tumor size and lymph node metastasis, whereas no significant relationship between IL-8 levels in peripheral veins and any variable was found. There was no correlation between VEGF and IL-8 levels in drainage veins. Large tumors, deeply invasive tumors, lymph node involvement, venous invasion and high IL-8 levels in drainage veins were all significantly associated with shorter disease-free survival, although multivariate analysis revealed that lymph node involvement was the only independent prognostic factor. In conclusion, the measurement of IL-8 levels in drainage veins of GC patients may reflect production mainly by the primary lesion and is valuable as an indicator of risk for recurrent disease.

PURPOSE: In this study, we measured the serum interleukin-8 (IL-8) levels in patients with hepatocellular carcinoma (HCC) to evaluate its correlation with clinicopathological features and prognosis. EXPERIMENTAL DESIGN: ELISA was used to detect the concentrations of IL-8, vascular endothelial growth factor, and macrophage migration inhibitory factor in preoperative sera of 59 patients with resection of HCC and 15 healthy subjects. RESULTS: Preoperative serum IL-8 was found to be significantly elevated in patients with HCC compared with healthy subjects (median, 17.6 versus 1.0 pg/ml, P=0.046). The levels of IL-8 correlated significantly with a large tumor size (>5 cm), absence of tumor capsule, presence of venous invasion, and advanced pathological tumor-node-metastasis stage. Serum IL-8 level was a significant prognostic factor in terms of disease-free and overall survival. Patients with a serum IL-8 level of >17.6 pg/ml had a poorer disease-free survival than those with a level of <17.6 pg/ml (median disease-free survival 4.7 versus 19.2 months). Multivariate analyses showed that serum IL-8 level was a significant and independent prognostic factor of survival. CONCLUSIONS: Significant correlations of serum IL-8 levels with tumor size and tumor stage suggest that IL-8 may be directly or indirectly involved in the progression of HCC. These findings indicate that serum IL-8 may be a useful biological marker of tumor invasiveness and an independent prognostic factor for patients with HCC.

Rapid growth of cancer cells often creates insufficient supply of oxygen and nutrients in the tumour nest. The frequent detection of hypoxia-inducible factor (HIF) and interleukin-8 (IL-8) in afflicted tissues suggests that IL-8 expression could be associated with elevated levels of HIF. Recently, we found that hypoxia also upregulated the expression of hepatocyte growth factor (HGF) in lung adenocarcinoma (LAD) cells. However, the relationship between HGF and IL-8 has not been investigated in LAD cells. In this study, we found that HGF induced IL-8 expression in LAD. Interestingly, hypoxia also increased the level of prostaglandin F(2alpha) (PGF(2alpha)), a product of dihydrodiol dehydrogenase (DDH). When expression of DDH was suppressed by siRNA, the levels of PGF(2alpha), HGF and IL-8 were reduced; however, their levels returned to normal after DDH was reintroduced. These data suggest that hypoxia induces biosynthesis of PGF(2alpha), which then activates HGF and IL-8 expression. The results provide a reasonable explanation of how PGF(2alpha), HGF and IL-8 exert their effects on cancer cell metastasis.

OBJECTIVE: The aim of this study was to evaluate the prognostic value of VEGF and IL-8 in pleural effusion in patients with lung cancer. MATERIALS AND METHOD: Commercially available ELISA was used to determine VEGF and IL-8 levels. RESULTS: The level of VEGF showed significant correlations with lymph node metastasis and distant metastasis. But, IL-8 was only correlated with lymph node metastasis. Univariate and multivariate analysis revealed elevated VEGF level was an independent predictor of shorter OS and DFS. CONCLUSION: VEGF could be an important component that contributes to pleural effusion formation, and an important prognostic factor for lung cancer.

Inflammation facilitates tumor progression including metastasis. Interleukin-8 (IL-8) is a chemokine that regulates polymorphonuclear neutrophil (PMN) mobilization and activity and we hypothesize that this cytokine influences tumor behavior. We have demonstrated that IL-8 is crucial for PMN-mediated melanoma extravasation under flow conditions. In addition, IL-8 is up-regulated in PMNs upon co-culturing with melanoma cells. Melanoma cells induce IkappaB-alpha degradation in PMNs indicating that NF-kappaB signaling is active in PMNs. Furthermore, the production of IL-8 in PMNs is NF-kappaB dependent. We have further identified that interleukin-6 (IL-6) and interleukin-1beta (IL-1beta) from PMN-melanoma co-cultures synergistically contribute to IkappaB-alpha degradation and IL-8 synthesis in PMNs. Taken together, these findings show that melanoma cells induce PMNs to secrete IL-8 through activation of NF-kappaB and suggest a model in which this interaction promotes a microenvironment that is favorable for metastasis.

CXCL-8, a chemokine secreted by melanoma and stromal cells, serves as a growth and angiogenic factor for melanoma progression. This study evaluated how modulation of CXCL-8 levels in melanoma cell lines with different tumorigenic and metastatic potentials affected multiple tumor phenotypes. A375P cells (CXCL-8 low expressor) were stably transfected with a CXCL-8 mammalian expression vector to overexpress CXCL-8, whereas A375SM cells (CXCL-8 high expressor) were transfected with a CXCL-8 antisense expression vector to suppress CXCL-8 expression. Subsequent cell proliferation, migration, invasion, and soft-agar colony formation were analyzed, and in vivo tumor growth and metastasis were evaluated using mouse xenograft models. Our data demonstrate that overexpression of CXCL-8 significantly enhanced primary tumor growth and lung metastasis, accompanied by increased microvessel density in vivo, as compared with vector control-transfected cells. We also observed increased clonogenic ability, growth, and invasive potential of CXCL-8 overexpressing cells in vitro. Knockdown of CXCL-8 using an antisense vector resulted in increased cell death and reduced tumor growth relative to control. Taken together, these data confirm that CXCL-8 expression plays a critical role in regulating multiple cellular phenotypes associated with melanoma growth and metastasis.

Interleukin 8 (IL-8) is a member of the alpha chemokine family of cytokines originally identified as a neutrophil chemoattractant. Recently, we reported that elevated levels of IL-8, but not parathyroid hormone-related protein (PTHrP), correlated with increased bone metastasis in a population of human breast cancer cells. We hypothesized that IL-8 expression by breast cancer cells would either indirectly influence osteoclastogenesis via nearby stromal cells or directly influence osteoclast differentiation and activity. In the present study, we investigated the role of IL-8 in the process of osteoclast formation and bone resorption, which is associated with metastatic breast cancer. The addition of recombinant human (rh) IL-8 (10 ng/ml) to cultures of stromal osteoblastic cells stimulated both RANKL mRNA expression and protein production, with no effect on the expression of osteoprotegerin. In addition, rhIL-8 also directly stimulated the differentiation of human peripheral blood mononuclear cells into bone-resorbing osteoclasts. In these cultures, IL-8 was able to stimulate human osteoclast formation even in the presence of excess (200 ng/ml) RANK-Fc. The effect of IL-8 on osteoclasts and their progenitors was associated with the cell surface expression of the IL-8-specific receptor (CXCR1) on the cells. These results demonstrate a direct effect of IL-8 on osteoclast differentiation and activity. Together, these data implicate IL-8 in the osteolysis associated with metastatic breast cancer.

In the last decade, several groups have shown a direct correlation between the inappropriate or ectopic release of interleukin (IL)-8 by tumor cells in vitro and their growth and metastatic potential using in vivo models of tumor growth. IL-8 is a potent neutrophil chemoattractant. Neutrophils, as "early responders" to wounds and infections, release enzymes to remodel the extracellular matrix of the tissues through which they migrate to reach the site of the wound or infection. It is proposed that the host's cellular response to IL-8 released by tumor cells enhances angiogenesis and contributes to tumor growth and progression. The activities released by the responding neutrophils could serve as enablers of tumor cell migration through the extracellular matrix, helping them enter the vasculature and journey to new, metastatic sites. The reactive oxygen species produced by neutrophilic oxidases to kill invading organisms have the potential to interact with tumor cells to attenuate their apoptotic cascade and increase their mutational rate. It is proposed that the increase in metastatic potential of tumors ectopically releasing IL-8 is, in part, attributable to their ability to attract neutrophils. Discussed here are possible mechanisms by which the neutrophils responding to ectopic IL-8 contribute to the in vivo growth, progression, and metastatic potential of tumor cells. Possible targets are also presented for the development of therapies to attenuate the effects of the ectopic IL-8 release by tumor cells.

OBJECTIVE: To investigate the expressions of matrix metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8) in nasopharyngeal carcinoma and their association with Epstein-Barr virus latent membrane protein-1 (LMP-1). METHOD: The expressions of MMP-9, IL-8 and LMP-1 were immunohistochemical studied in 53 nasopharyngeal carcinoma sections. We statistically analyzed the correlation of these data and also the relationship between the clinical features and the experimental data of these patients. RESULT: The positive expression rate of MMP-9, IL-8 and LMP-1 were all 66.04% (35/53) and their average expression score were (33.19 +/- 29.73)%, (33.46 +/- 30.23)%, (35.49 +/- 29.63)% respectively. The expressions of MMP-9 and IL-8 both showed positive correlation with the expression of LMP-1 (r = 0.792, 0.786 respectively). The expressions of MMP-9, IL-8 and LMP-1 showed significant relationship with lymph nodes metastasis (P < 0.05), but no-significant association with age, gender, pathological classification, and clinical stage. CONCLUSION: The expressions of MMP-9, IL-8 and LMP-1 were significantly associated with neck lymph nodes metastasis in nasopharyngeal carcinoma. The correlation between LMP-1 and MMP-9, IL-8 showed LMP-1 might enhance neck lymph nodes metastasis by up-regulating the expressions of MMP-9 and IL-8.

BACKGROUND AND OBJECTIVES: We aim at the association of macrophage migration inhibitory factor (MIF) with neovascularization and survival of nasopharyngeal carcinoma (NPC), and determine whether MIF is a valuable prognostic predictor for NPC patients. METHODS: One hundred and forty one cases of NPC and 25 normal tissues of nasopharynx were collected. The expression of MIF and interleukin 8 (IL-8) was evaluated in tissues microarray by immunostaining. Intratumoral microvessel density (IMD) in relation to immunostainings and clinicopathological factors were analyzed statistically as well as the follow-up data of patients. RESULTS: High-expression of both MIF (69.5%) and IL-8 (56.0%) were significantly associated with increased microvessels and lymph node metastasis. High-expression of MIF, IL-8 and higher level of IMD were correlated with either patients' overall survival or disease-specific survival in univariate analysis, but only angiogenesis and lymph node status exhibited in relation to survival of patients as independent prognostic factor of NPC by multivariate analysis. In addition, high-expression of MIF and higher level of IMD were closely associated with locoregional failure of NPC patients. CONCLUSIONS: MIF may contribute to lymph node metastasis in NPC by inducing angiogenesis through the way of upregulation of IL-8 expression in an autocrine EBV-independent pathway.

OBJECTIVE: cancer patients usually develop malnutrition which may alter their innate immune system integrity. The aim of this study was to investigate the clinical relevance of chemokine response after lipopolysaccharide (LPS)-stimulation in metastatic non-small cell lung cancer (NSCLC). METHODS: Blood samples from metastatic NSCLC patients were incubated with LPS before the onset of systemic therapy. Interleukin (IL)-6 and IL-8 levels at baseline and after LPS-stimulation were measured and the fold change compared to baseline levels was evaluated as the stimulation index for each cytokine per patient. Results were correlated with sex, age, smoking status, histologic subtype, performance status (PS), albumin, Mini Nutritional Assessment (MNA) status and clinical outcomes. RESULTS: Totally 103 patients were evaluated. Mean (+/-SD) stimulation index was 37.6 (+/-57.8) for IL-6 and 76.7 (+/-133.4) for IL-8. The disease control rate after first-line chemotherapy was 44/80 (55 %) and the mean (+/-SD) progression-free survival (PFS) and overall survival (OS) were 4.2 (+/-3.9) and 9.2 (+/-1.1) months, respectively. MNA, PS, albumin, IL-6 and IL-8 stimulation indices were univariately associated with PFS and OS. IL-8 stimulation index emerged as an independent predictor of both PFS and OS, along with PS, and albumin levels. CONCLUSION: The extent of IL-6 and IL-8 stimulation after ex vivo induction with LPS is an important predictor of clinical outcome in metastatic NSCLC patients.

Lysophosphatidic acid (LPA) is a bioactive lipid with a growth factor-like activity on a large range of cell types. Several pieces of evidence raise the possibility that LPA may play an important role in bone metastasis. Bone is a frequent metastatic site for oral cancer. However, the role of LPA in the progression of oral cancer metastasis to the bone is poorly understood. Here, we provide evidence for the role of LPA in the progression of oral cancer bone metastases and its regulatory mechanism. LPA induced the secretion of IL-6 and IL-8 in oral squamous cell carcinoma (OSCC). LPA-stimulated secretion of IL-6 and IL-8 is partly dependent on the LPA and EGF receptor (EGFR) pathways. ERK1/2 and Akt-mediated NF-kappaB and AP-1 were responsible for the LPA-induced IL-6 and IL-8 secretion. Moreover, conditioned medium (CM) derived from the LPA-stimulated OSCC supported osteoclast formation in bone marrow-derived macrophages (BMMs). Neutralization against both human IL-6 and IL-8 suppressed osteoclast formation induced by CM derived from the LPA-stimulated OSCC. Direct treatment with recombinant IL-6 (rIL-6) and/or soluble IL-6 receptor (sIL-6R), or IL-8 (rIL-8) reproduced the effect of the CM derived from the LPA-stimulated OSCC on osteoclast formation. In addition, CM derived from the LPA-stimulated OSCC induced receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) expression in human osteoblasts and direct treatment with rIL-6 and/or sIL-6R or rIL-8 mimicked the effect of the CM derived from the LPA-stimulated OSCC for RANKL expression. Taken together, LPA may be a potent inducer of osteolytic factor IL-6 and IL-8 in OSCC. LPA-induced IL-6 and IL-8 exerted propound effects on RANKL expression in osteoblast and thereby promoted osteoclast formation from osteoclast precursors.

CONTEXT: Development of novel strategies in the treatment of advanced thyroid cancer are needed. Our laboratory has previously identified a role for nuclear factor kappaB (NF-kappaB) signaling in human thyroid cancer cell growth, survival, and invasion. OBJECTIVE: Our goal was to establish the role of NF-kappaB signaling on thyroid cancer growth and metastases in vivo and to begin to dissect mechanisms regulating this effect. SETTING AND DESIGN: We examined tumor formation of five thyroid cancer cell lines in an in vivo model of thyroid cancer and observed tumor establishment in two of the cell lines (8505C and BCPAP). RESULTS: Inhibition of NF-kappaB signaling by overexpression of a dominant-negative IkappaBalpha (mIkappaBalpha) significantly inhibited thyroid tumor growth in tumors derived from both cell lines. Further studies in an experimental metastasis model demonstrated that NF-kappaB inhibition impaired growth of tumor metastasis and prolonged mouse survival. Proliferation (mitotic index) was decreased in 8505C tumors, but not in BCPAP tumors, while in vitro angiogenesis and in vivo tumor vascularity were significantly inhibited by mIkBalpha only in the BCPAP cells. Cytokine antibody array analysis demonstrated that IL-8 secretion was blocked by mIkappaBalpha expression. Interestingly, basal NF-kappaB activity and IL-8 levels were significantly higher in the two tumorigenic cell lines compared with the nontumorigenic lines. Furthermore, IL-8 transcript levels were elevated in high-risk human tumors, suggesting that NF-kappaB and IL-8 are associated with more aggressive tumor behavior. CONCLUSIONS: These studies suggest that NF-kappaB signaling is a key regulator of angiogenesis and growth of primary and metastatic thyroid cancer, and that IL-8 may be an important downstream mediator of NF-kappaB signaling in advanced thyroid cancer growth and progression.