Expression of cyclooxygenase-2 in advanced stage ovarian serous carcinoma: correlation with tumor cell proliferation, apoptosis, angiogenesis, and survival

Racial Differences in Vaginal Fluid Metabolites and Association with Systemic Inflammation Markers among Ovarian Cancer Patients: A Pilot Study

The vaginal microbiome differs by race and contributes to inflammation by directly producing or consuming metabolites or by indirectly inducing host immune response, but its potential contributions to ovarian cancer (OC) disparities remain unclear. In this exploratory cross-sectional study, we examine whether vaginal fluid metabolites differ by race among patients with OC, if they are associated with systemic inflammation, and if such associations differ by race. Study participants were recruited from the Ovarian Cancer Epidemiology, Healthcare Access, and Disparities Study between March 2021 and September 2022. Our study included 36 study participants with ovarian cancer who provided biospecimens; 20 randomly selected White patients and all 16 eligible Black patients, aged 50-70 years. Acylcarnitines (n = 45 species), sphingomyelins (n = 34), and ceramides (n = 21) were assayed on cervicovaginal fluid, while four cytokines (IL-1β, IL-10, TNF-α, and IL-6) were assayed on saliva. Seven metabolites showed >2-fold differences, two showed significant differences using the Wilcoxon rank-sum test (p < 0.05; False Discovery Rate > 0.05), and 30 metabolites had coefficients > ±0.1 in a Penalized Discriminant Analysis that achieved two distinct clusters by race. Arachidonoylcarnitine, the carnitine adduct of arachidonic acid, appeared to be consistently different by race. Thirty-eight vaginal fluid metabolites were significantly correlated with systemic inflammation biomarkers, irrespective of race. These findings suggest that vaginal fluid metabolites may differ by race, are linked with systemic inflammation, and hint at a potential role for mitochondrial dysfunction and sphingolipid metabolism in OC disparities. Larger studies are needed to verify these findings and further establish specific biological mechanisms that may link the vaginal microbiome with OC racial disparities.

Overcoming adaptive resistance to anti-VEGF therapy by targeting CD5L

Antiangiogenic treatment targeting the vascular endothelial growth factor (VEGF) pathway is a powerful tool to combat tumor growth and progression; however, drug resistance frequently emerges. We identify CD5L (CD5 antigen-like precursor) as an important gene upregulated in response to antiangiogenic therapy leading to the emergence of adaptive resistance. By using both an RNA-aptamer and a monoclonal antibody targeting CD5L, we are able to abate the pro-angiogenic effects of CD5L overexpression in both in vitro and in vivo settings. In addition, we find that increased expression of vascular CD5L in cancer patients is associated with bevacizumab resistance and worse overall survival. These findings implicate CD5L as an important factor in adaptive resistance to antiangiogenic therapy and suggest that modalities to target CD5L have potentially important clinical utility.

Chitosan nanoparticles loaded with aspirin and 5-fluororacil enable synergistic antitumour activity through the modulation of NF-κB/COX-2 signalling pathway

Based on the enhancement of synergistic antitumour activity to treat cancer and the correlation between inflammation and carcinogenesis, the authors designed chitosan nanoparticles for co-delivery of 5-fluororacil (5-Fu: an as anti-cancer drug) and aspirin (a non-steroidal anti-inflammatory drug) and induced synergistic antitumour activity through the modulation of the nuclear factor kappa B (NF-κB)/cyclooxygenase-2 (COX-2) signalling pathways. The results showed that aspirin at non-cytotoxic concentrations synergistically sensitised hepatocellular carcinoma cells to 5-Fu in vitro. It demonstrated that aspirin inhibited NF-κB activation and suppressed NF-κB regulated COX-2 expression and prostaglandin E2 (PGE2) synthesis. Furthermore, the proposed results clearly indicated that the combination of 5-Fu and aspirin by chitosan nanoparticles enhanced the intracellular concentration of drugs and exerted synergistic growth inhibition and apoptosis induction on hepatocellular carcinoma cells by suppressing NF-κB activation and inhibition of expression of COX-2.

Urinary PGE-M Levels and Risk of Ovarian Cancer

BACKGROUND

Regular aspirin use may lower ovarian cancer risk by blocking the cyclooxygenase enzymes, resulting in lower expression of prostaglandins, including prostaglandin E2 (PGE2). We evaluated whether higher prediagnosis PGE-M (a urinary biomarker of PGE2) was associated with increased ovarian cancer risk in three prospective cohorts.

METHODS

We conducted a case-control study nested in the Nurses' Health Study (NHS), NHSII, and Shanghai Women's Health Study. Our analyses included 304 cases of epithelial ovarian cancer diagnosed from 1996 to 2015 and 600 matched controls. We measured urinary PGE-M using LC/MS with normalization to creatinine. Measures from each study were recalibrated to a common standard. We estimated ORs and 95% confidence intervals (CI) using conditional logistic regression, with PGE-M levels modeled in quartiles. Multivariable models were adjusted for ovarian cancer risk factors.

RESULTS

There was no evidence of an association between urinary PGE-M levels and ovarian cancer risk for women with PGE-M levels in the top versus bottom quartile (OR = 0.80; 95% CI, 0.51-1.27; P trend = 0.37). We did not observe heterogeneity by histotype (P = 0.53), and there was no evidence of effect modification by body mass index (P interaction = 0.82), aspirin use (P interaction = 0.59), or smoking (P interaction = 0.14).

CONCLUSIONS

Prediagnosis urinary PGE-M levels were not significantly associated with ovarian cancer risk. Larger sample sizes are needed to consider a more modest association and to evaluate associations for specific tumor subtypes.

IMPACT

Systemic prostaglandin levels do not appear strongly associated with ovarian cancer risk. Future research into aspirin use and ovarian cancer risk should consider local prostaglandins and prostaglandin-independent mechanisms.

Coiled-Coil and C2 Domain-Containing Protein 1A (CC2D1A) Promotes Chemotherapy Resistance in Ovarian Cancer

Recurrence within 6 months of the last round of chemotherapy is clinically defined as platinum-resistant ovarian cancer. Gene expression associated with early recurrence may provide insights into platinum resistant recurrence. Prior studies identified a 14-gene model that accurately predicted early or late recurrence in 86% of patients. One of the genes identified was CC2D1A (encoding coiled-coil and C2 domain containing 1A), which showed higher expression in tumors from patients with early recurrence. Here, we show that CC2D1A protein expression was higher in cisplatin-resistant ovarian cancer cell lines compared to cisplatin-sensitive cell lines. In addition, immunohistochemical analysis of patient tumors on a tissue microarray (n = 146) showed that high levels of CC2D1A were associated with a significantly worse overall and progression-free survival (p = 0.0002 and p = 0.006, respectively). To understand the contribution of CC2D1A in chemoresistance, we generated shRNA-mediated knockdown of CC2D1A in SKOV3ip and PEO4 cell lines. Cell death and clonogenic assays of these isogenic clonal lines clearly showed that downregulation of CC2D1A resulted in increased sensitivity to cisplatin and paclitaxel in ovarian cancer cells. Moreover, nude mice bearing SKOV3ip xenografts with stably downregulated CC2D1A were more sensitive to chemotherapy as evidenced by a significantly longer survival time compared to xenografts derived from cells stably transduced with non-targeting shRNA. These results suggest CC2D1A promotes chemotherapy resistance in ovarian cancer.

EP3 receptor is a prognostic factor in TA-MUC1-negative ovarian cancer

PURPOSE

Prostaglandin-mediated inflammatory reactions play a major role in different cancers. Recently, it has been observed that prostaglandin E2-receptor 3 (EP3) might be an independent prognostic factor for overall survival in cervical and endometrial cancer. The role of EP3 expression in ovarian cancer is currently unknown.

METHODS

EP3 expression was analyzed by immunohistochemistry in 156 patient samples using the IR-scoring system. Expression levels were correlated with clinical and pathological parameters and with overall survival (OS) to assess for prognostic relevance. Data analysis was performed using Spearman's correlations, Kruskal-Wallis test and Kaplan-Meier estimates.

RESULTS

EP3 expression was significantly higher in clear-cell carcinoma (p < 0.001) compared to the other histological subtypes. No further correlations with clinical parameters could be found. EP3 expression correlated significantly with FSH-receptor expression (p < 0.001), galectin-1 expression in the tumor (p = 0.012) and with cytoplasmatic TA-MUC1 expression (p = 0.001). None of these parameters showed significant correlation with OS. In the TA-MUC1 negative subgroup, EP3 negative patients showed significantly longer OS (median OS: 102 months vs. 34 months in EP3 positive patients, p = 0.035), while EP3 did not appear to have prognostic relevance in the TA-MUC1-positive subgroup.

CONCLUSION

The potential prognostic relevance of EP3 expression for OS in TA-MUC1 negative patients might reflect an interplay between the COX and the MUC1 pathway, as it has been shown that MUC1 could induce COX2 expression. Our findings support the importance of the prostanoid signaling in TA-MUC1 negative ovarian cancer; however, future studies are necessary to characterize specific pathways and possible interactions.

Dual Actions of Ketorolac in Metastatic Ovarian Cancer

Cytoreductive surgery and chemotherapy are cornerstones of ovarian cancer treatment, yet disease recurrence remains a significant clinical issue. Surgery can release cancer cells into the circulation, suppress anti-tumor immunity, and induce inflammatory responses that support the growth of residual disease. Intervention within the peri-operative window is an under-explored opportunity to mitigate these consequences of surgery and influence the course of metastatic disease to improve patient outcomes. One drug associated with improved survival in cancer patients is ketorolac. Ketorolac is a chiral molecule administered as a 1:1 racemic mixture of the S- and R-enantiomers. The S-enantiomer is considered the active component for its FDA indication in pain management with selective activity against cyclooxygenase (COX) enzymes. The R-enantiomer has a previously unrecognized activity as an inhibitor of Rac1 (Ras-related C3 botulinum toxin substrate) and Cdc42 (cell division control protein 42) GTPases. Therefore, ketorolac differs from other non-steroidal anti-inflammatory drugs (NSAIDs) by functioning as two distinct pharmacologic entities due to the independent actions of each enantiomer. In this review, we summarize evidence supporting the benefits of ketorolac administration for ovarian cancer patients. We also discuss how simultaneous inhibition of these two distinct classes of targets, COX enzymes and Rac1/Cdc42, by S-ketorolac and R-ketorolac respectively, could each contribute to anti-cancer activity.

High Ki-67 expression is significantly associated with poor prognosis of ovarian cancer patients: evidence from a meta-analysis

OBJECTIVE

The prognostic significance of Ki-67 expression in patients with ovarian cancer was controversial in various studies. Therefore, we carried out a meta-analysis to determine the prognostic significance of Ki-67 in ovarian cancer patients.

METHODS

We searched PubMed, Cochrane Library, EMBASE, Web of Knowledge, China National Knowledge Infrastructure database and WanFang digital database for eligible studies from January 1, 1990 to June 1, 2017. The pooled hazard ratios and 95% confidence intervals were calculated to assess the prognostic significance of Ki-67 expression for overall survival in ovarian cancer patients.

RESULTS

Finally, 38 eligible studies and 5004 ovarian cancer patients were included in the current study. The pooled hazard ratio was 1.35 (95% confidence interval 1.24-1.46, P = 0.001) for overall survival in ovarian cancer patients. The funnel plot bias was obviously asymmetrical and Egger's test also detected significant publication bias (P = 0.001). The Contour-enhanced funnel plot with trim-and-fill method supplemented 11 dummy studies to balance the funnel plot and nine new supplementary studies were in area with statistical significance. Sensitivity analysis and cumulative meta-analysis further demonstrated that the association between high Ki-67 expression and poor overall survival of ovarian cancer patients was stable and reliable.

CONCLUSIONS

High Ki-67 expression is significantly related to poor overall survival and may serve as a prognostic biomarker for ovarian cancer patients.

The Role of Inflammation and Inflammatory Mediators in the Development, Progression, Metastasis, and Chemoresistance of Epithelial Ovarian Cancer

Inflammation plays a role in the initiation and development of many types of cancers, including epithelial ovarian cancer (EOC) and high grade serous ovarian cancer (HGSC), a type of EOC. There are connections between EOC and both peritoneal and ovulation-induced inflammation. Additionally, EOCs have an inflammatory component that contributes to their progression. At sites of inflammation, epithelial cells are exposed to increased levels of inflammatory mediators such as reactive oxygen species, cytokines, prostaglandins, and growth factors that contribute to increased cell division, and genetic and epigenetic changes. These exposure-induced changes promote excessive cell proliferation, increased survival, malignant transformation, and cancer development. Furthermore, the pro-inflammatory tumor microenvironment environment (TME) contributes to EOC metastasis and chemoresistance. In this review we will discuss the roles inflammation and inflammatory mediators play in the development, progression, metastasis, and chemoresistance of EOC.

The mannose receptor LY75 (DEC205/CD205) modulates cellular phenotype and metastatic potential of ovarian cancer cells

The molecular basis of epithelial ovarian cancer (EOC) dissemination is still poorly understood. Previously, we identified the mannose receptor LY75 gene as hypomethylated in high-grade (HG) serous EOC tumors, compared to normal ovarian tissues. LY75 represents endocytic receptor expressed on dendritic cells and so far, has been primarily studied for its role in antigen processing and presentation. Here we demonstrate that LY75 is overexpressed in advanced EOC and that LY75 suppression induces mesenchymal-to-epithelial transition (MET) in EOC cell lines with mesenchymal morphology (SKOV3 and TOV112), accompanied by reduction of their migratory and invasive capacity in vitro and enhanced tumor cell colonization and metastatic growth in vivo. LY75 knockdown in SKOV3 cells also resulted in predominant upregulation of functional pathways implicated in cell proliferation and metabolism, while pathways associated with cell signaling and adhesion, complement activation and immune response were mostly suppressed. Moreover, LY75 suppression had an opposite effect on EOC cell lines with epithelial phenotype (A2780s and OV2008), by directing epithelial-to-mesenchymal transition (EMT) associated with reduced capacity for in vivo EOC cell colonization, as similar/identical signaling pathways were reversely regulated, when compared to mesenchymal LY75 knockdown EOC cells.To our knowledge, this is the first report of a gene displaying such pleiotropic effects in sustaining the cellular phenotype of EOC cells and points to novel functions of this receptor in modulating EOC dissemination. Our data also support previous findings regarding the superior capacity of epithelial cancer cells in metastatic colonization of distant sites, compared to cancer cells with mesenchymal-like morphology.

Resveratrol promotes regression of renal carcinoma cells via a renin-angiotensin system suppression-dependent mechanism

The aim of the present study was to investigate the effect of resveratrol on renal carcinoma cells and explore possible renin-angiotensin system-associated mechanisms. Subsequent to resveratrol treatment, the cell viability, apoptosis rate, cytotoxicity levels, caspase 3/7 activity and the levels of angiotensin II (AngII), AngII type 1 receptor (AT1R), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) were evaluated in renal carcinoma cells. The effects of AngII, AT1R, VEGF and COX-2 on resveratrol-induced cell growth inhibition and apoptosis were also examined. The results indicated that resveratrol treatment may suppress growth, induce apoptosis, and decrease AngII, AT1R, VEGF and COX-2 levels in renal carcinoma ACHN and A498 cells. In addition, resveratrol-induced cell growth suppression and apoptosis were reversed when co-culturing with AT1R or VEGF. Thus, resveratrol may suppress renal carcinoma cell proliferation and induce apoptosis via an AT1R/VEGF pathway.

Expression of cyclooxygenase-2 in cervical cancer is associated with lymphovascular invasion

Cyclooxygenase-2 (COX-2) is associated with carcinogenesis and tumor progression. The current study analyzed the effect of COX-2 expression in patients with invasive squamous cervical cancer. Tissue samples from 123 cervical cancer patients were collected for a retrospective analysis using immunohistochemistry (IHC) with an antibody against COX-2. The clinical and survival data of the patients were analyzed. Positive staining for COX-2 (defined as an immunoreactivity score of ≥4) was detected in 28 patients (23%), with significantly higher percentages of staining in tumor cells compared with peritumoral stroma cells (P<0.001). COX-2 expression was significantly associated with lymphovascular space invasion (LVSI; P=0.017). The association of COX-2 expression with LVSI suggests a possible effect of COX-2 on tumor progression in cervical cancer. Further studies including larger patient collectives are required in order to perform analyses of clinical subgroups and patient survival.

SKP2/P27Kip1 pathway is associated with Advanced Ovarian Cancer in Saudi Patients

BACKGROUND

Ovarian cancer is the most common gynecological malignancy and constitutes the fifth leading cause of female cancer death. Some biological parameters have prognostic roles in patients with advanced ovarian cancer and their expression may contribute to tumor progression. The aim of this study was to investigate the potential prognostic value of SKP2, genes P27Kip1, K-ras, c-Myc, COX2 and HER2 genes expression in ovarian cancer.

MATERIALS AND METHODS

This study was performed on two hundred formalin fixed paraffin embedded ovarian cancer and normal adjacent tissues (NAT). Gene expression levels were assessed using real time PCR and Western blotting.

RESULTS

Elevated expression levels of SKP2, K-ras, c-Myc, HER2 and COX2 genes were observed in 61.5% (123/200), 92.5% (185/200), 74% (148/200), 96 % (192/200), 90% (180/200) and 78.5% (157/200) of cancer tissues, respectively. High expression of SKP2 and down-regulation of P27 was associated with advanced stages of cancer.

CONCLUSIONS

The association between high expression of c-Myc and SKP2 with low expression of P27 suggested that the Skp2-P27 pathway may play an important role in ovarian carcinogenesis. Reduced expression of P27 is associated with advanced stage of cancer and can be used as a biological marker in clinical routine assessment and management of women with advanced ovarian cancer.

Ovarian cancer microenvironment: implications for cancer dissemination and chemoresistance acquisition

Ovarian adenocarcinoma is characterized by a late detection, dissemination of cancer cells into the whole peritoneum, and the frequent acquisition of chemoresistance. If these particularities can be explained in part by intrinsic properties of ovarian cancer cells, an increased number of studies show the importance of the tumor microenvironment in tumor progression. Ovarian cancer cells can regulate the composition of their stroma in promoting the formation of ascitic fluid, rich in cytokines and bioactive lipids, and in stimulating the differentiation of stromal cells into a pro-tumoral phenotype. In return, cancer-associated fibroblasts, cancer-associated mesenchymal stem cells, tumor-associated macrophages, or other peritoneal cells, such as adipocytes and mesothelial cells can regulate tumor growth, angiogenesis, dissemination, and chemoresistance. This review focuses on the current knowledge about the roles of stromal cells and the associated secreted factors on tumor progression. We also summarize the different studies showing that targeting the microenvironment represents a great potential for improving the prognosis of patients with ovarian adenocarcinoma.

Impact of isoflurane on malignant capability of ovarian cancer in vitro

BACKGROUND

Metastatic recurrence of ovarian cancer is the foremost cause of postoperative mortality. With recent research indicating that inhalation of anaesthetics may influence cancer cell behaviour, this study investigated the effects of isoflurane on the expression of tumorigenic markers and proliferative capacity in ovarian cancer cells.

METHODS

Ovarian cancer (SK-OV3) cells were cultured and then exposed to 2% isoflurane for 2 h. The expression of markers involved in cell proliferation, angiogenesis, and migration were assessed up to 24 h after treatment using immunofluorescence staining, western blotting, and flow cytometry. The effects of isoflurane on in vitro angiogenesis and migration were also determined.

RESULTS

Isoflurane exposure significantly increased insulin-like growth factor (IGF)-1 and IGF-1R expression, cell cycle progression, and cell proliferation in SK-OV3 cells. Increased expression of the angiogenic markers vascular endothelial growth factor (VEGF) by 56% (P<0.05) and angiopoietin-1 by 62% (P<0.05) was also observed 24 h after isoflurane exposure together with an enhanced in vitro angiogenesis. Cell migration was significantly increased after exposure to isoflurane together with increased production of both matrix metalloproteinases 2 and 9 (both P<0.05) by almost five-fold relative to control. These effects were abolished when IGF-1R signalling was blocked either by neutralizing antibody or by small interfering RNA.

CONCLUSIONS

Our data indicate that isoflurane increases the malignant potential of ovarian cancer cells through the up-regulation of markers associated with the cell cycle, proliferation, and angiogenesis. This study warrants further investigations.

Meloxicam executes its antitumor effects against hepatocellular carcinoma in COX-2- dependent and -independent pathways

BACKGROUND

Cyclooxygenase (COX)-2 is overexpressed in many types of cancers including hepatocellular carcinoma (HCC). Meloxicam, a selective COX-2 inhibitor, has shown potential therapeutic effects against HCC, but the mechanisms accounting for its anti-cancer activities remain unclear.

METHODS AND FINDINGS

Meloxicam inhibited the ability of human HCC cells expressing higher levels of COX-2 to migrate, invade, adhere and form colonies through upregulating the expression of E-cadherin and downregulating the expression of matrix metalloproteinase (MMP) -2. Meloxicam induced cell apoptosis by upregulating pro-apoptotic proteins including Bax and Fas-L, and downregulating anti-apoptotic proteins including survivin and myeloid cell leukemia-1 (Mcl-1), through inhibiting phosphorylation of AKT. Addition of prostaglandin E2 (PGE2), the major product of COX-2, could abrogate the effects of meloxicam on the expression of survivin and myeloid cell leukemia-1 (Mcl-1), but not Bax and Fas-L, indicating that meloxicam induces cell apoptosis via both COX-2-dependent and -independent pathways. Meloxicam also induced cell autophagy by upregulating Beclin 1 and light chain 3-II. Specific inhibition of autophagy by 3-methyladenine and chloroquine had little effect on cell apoptosis but could enhance the pro-apoptotic effects of meloxicam by further upregulating the expression of Bax.

CONCLUSIONS

Meloxicam executes its antitumor effects by targeting the COX-2/MMP-2/E-cadherin, AKT, apoptotic and autophagic pathways in COX-2-dependent and -independent pathways, and inhibition of cell autophagy could help to overcome the resistance to meloxicam-induced apoptosis in HCC.

Meloxicam executes its antitumor effects against hepatocellular carcinoma in COX-2- dependent and -independent pathways

Background

Cyclooxygenase (COX)-2 is overexpressed in many types of cancers including hepatocellular carcinoma (HCC). Meloxicam, a selective COX-2 inhibitor, has shown potential therapeutic effects against HCC, but the mechanisms accounting for its anti-cancer activities remain unclear.

Methods and Findings

Meloxicam inhibited the ability of human HCC cells expressing higher levels of COX-2 to migrate, invade, adhere and form colonies through upregulating the expression of E-cadherin and downregulating the expression of matrix metalloproteinase (MMP) -2. Meloxicam induced cell apoptosis by upregulating pro-apoptotic proteins including Bax and Fas-L, and downregulating anti-apoptotic proteins including survivin and myeloid cell leukemia-1 (Mcl-1), through inhibiting phosphorylation of AKT. Addition of prostaglandin E2 (PGE2), the major product of COX-2, could abrogate the effects of meloxicam on the expression of survivin and myeloid cell leukemia-1 (Mcl-1), but not Bax and Fas-L, indicating that meloxicam induces cell apoptosis via both COX-2-dependent and -independent pathways. Meloxicam also induced cell autophagy by upregulating Beclin 1 and light chain 3-II. Specific inhibition of autophagy by 3-methyladenine and chloroquine had little effect on cell apoptosis but could enhance the pro-apoptotic effects of meloxicam by further upregulating the expression of Bax.

Conclusions

Meloxicam executes its antitumor effects by targeting the COX-2/MMP-2/E-cadherin, AKT, apoptotic and autophagic pathways in COX-2-dependent and -independent pathways, and inhibition of cell autophagy could help to overcome the resistance to meloxicam-induced apoptosis in HCC.

Prognostic biomarkers in endometrial and ovarian carcinoma

This article reviews the main prognostic and predictive biomarkers of endometrial (EC) and ovarian carcinoma (OC). In EC, prognosis still relies on conventional pathological features such as histological type and grade, as well as myometrial or lymphovascular space invasion. Estrogen receptor, p53, Ki-67, and ploidy analysis are the most promising biomarkers among a long list of molecules that have been proposed. Also, a number of putative predictive biomarkers have been proposed in molecular targeted therapy. In OC, prognosis is predominantly dependent on disease stage at diagnosis and the extent of residual disease at primary operation. Diagnostic markers which aid in establishing histological type in OC are available. However, not a single universally accepted predictive or prognostic marker exists to date. Targeted therapy has been growingly focused at in recent years, in view of the frequent development of chemoresistance at recurrent disease. The present review emphasizes the crucial role of correct pathological classification and stringent selection criteria of the material studied as basis for any evaluation of biological markers. It further emphasizes the promise of targeted therapy in EC and OC, while simultaneously highlighting the difficulties remaining before this can become standard of care.

Cross-talk between EphA2 and BRaf/CRaf is a key determinant of response to Dasatinib

PURPOSE

EphA2 is an attractive therapeutic target because of its diverse roles in cancer growth and progression. Dasatinib is a multikinase inhibitor that targets EphA2 and other kinases. However, reliable predictive markers and a better understanding of the mechanisms of response to this agent are needed.

EXPERIMENTAL DESIGN

The effects of dasatinib on human uterine cancer cell lines were examined using a series of in vitro experiments, including MTT, Western blot analysis, and plasmid transfection. In vivo, an orthotopic mouse model of uterine cancer was utilized to identify the biologic effects of dasatinib. Molecular markers for response prediction and the mechanisms relevant to response to dasatinib were identified by using reverse phase protein array (RPPA), immunoprecipitation, and double immunofluorescence staining.

RESULTS

We show that high levels of CAV-1, EphA2 phosphorylation at S897, and the status of PTEN are key determinants of dasatinib response in uterine carcinoma. A set of markers essential for dasatinib response was also identified and includes CRaf, pCRaf(S338), pMAPK(T202/Y204) (mitogen-activated protein kinase [MAPK] pathway), pS6(S240/244), p70S6k(T389) (mTOR pathway), and pAKT(S473). A novel mechanism for response was discovered whereby high expression level of CAV-1 at the plasma membrane disrupts the BRaf/CRaf heterodimer and thus inhibits the activation of MAPK pathway during dasatinib treatment.

CONCLUSIONS

Our in vitro and in vivo results provide a new understanding of EphA2 targeting by dasatinib and identify key predictors of therapeutic response. These findings have implications for ongoing dasatinib-based clinical trials.

Prognostic significance of cyclooxygenase-2 in cervical cancer: a meta-analysis

Published data on the prognostic value of cyclooxygenase-2 (COX-2) overexpression in cervical cancer are conflicting and heterogeneous. We performed a meta-analysis to more precisely estimate its prognostic significance. The pooled hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were used to estimate the effects. Twenty-three studies with 1,477 cervical cancer patients were selected to evaluate the association between COX-2 and overall survival (OS), disease-free survival (DFS), response to chemoradiation (RC) and clinicopathological parameters. High COX-2 expression predicted poor OS (HR: 2.53, 95% CI: 1.54-4.18), DFS (HR: 2.41, 95% CI: 1.58-3.69) and RC (OR: 3.03, 95% CI: 1.97-4.64). Subgroup analyses showed that COX-2 overexpression was related significantly with poor OS in patients treated by chemoradiation or surgery, and in patients with squamous cell carcinoma, respectively. Besides, COX-2 overexpression was related significantly with poor DFS in chemoradiation subgroup. Furthermore, COX-2 overexpression was associated with poor RC in patients who received "FP" regimen or "P" regimen. Additionally, there were significant associations between COX-2 expression and all clinicopathological parameters except tumor grade. The pooled ORs (95% CI) were as follows: 1.49 (1.09-2.04) for age, 1.77 (1.22-2.56) for lymph node metastasis, 1.04 (0.74-1.47) for tumor grade, 1.71 (1.12-2.64) for tumor size, 2.38 (1.28-4.45) for FIGO stage, 3.96 (2.32-6.77) for histological type, 2.45(1.10-5.42) for parametrical involvement. This meta-analysis indicated that COX-2 overexpression might be an unfavorable prognostic and a chemoradiation resistance predictive factor for cervical cancer; it could potentially help to stratify patients further in clinical treatment.

Angiogenesis and molecular markers in advanced epithelial ovarian cancer: a retrospective study

OBJECTIVE

The role of molecular markers in ovarian cancer is still a matter of debate. Angiogenesis is a necessary condition for tumor growth. Hypoxia induces angiogenesis, and cyclooxygenase-2 (COX-2), p53 and HER2 are involved in cancer proliferation and angiogenesis regulation. The aims of this study were to evaluate the relationship between intratumoral microvessel density (IMD) and the expression of molecular markers that affect angiogenesis (COX-2, p53 and HER2) in advanced epithelial ovarian cancer (EOC), to analyze their prognostic and predictive value and their association with clinicopathological features, such as serum hemoglobin level at diagnosis (Hb).

METHODS

Immunohistochemical staining with CD34 (for IMD), COX-2, p53 and HER2 antibodies was performed in 113 patients with advanced EOC who had undergone primary surgery. Clinicopathological data were collected and statistical analyses were performed.

RESULTS

Neither IMD, COX-2 nor HER2 had any predictive or prognostic value in EOC. A relationship that approached statistical significance was found between p53 expression and a complete response to treatment (p=0.05). p53 expression and tumor grade were inversely associated (p=0.012). Hb<12g/dl had predictive value (p=0.02).

CONCLUSIONS

In our series IMD, COX-2 and HER2 had neither prognostic nor predictive value in advanced EOC. p53 and Hb may be predictive factors. The results and clinical usefulness of immunohistochemistry are controversial. Further evaluations are required to determine whether the serum levels of molecular markers correlate with the results of immunohistochemical assays and whether they offer any prognostic and/or predictive value. Targeted therapy remains the ultimate goal of these studies.

Clinicopathologic Implications of the Epidermal Growth Factor Receptor, Cyclooxygenase 2 Expression, and Human Papillomavirus Status in Squamous Cell Carcinoma of the Uterine Cervix in the Elderly

Objectives:

To find information on invasive squamous cervical carcinoma in the elderly, 110 invasive squamous cervical carcinomas obtained from 2 groups of patients (aged <60 and >60 years) were analyzed for human papillomavirus (HPV) status by polymerase chain reaction study, for immunohistochemical epidermal growth factor receptor (EGFR), cyclooxygenase 2 (Cox-2) expression, and clinicopathologic features.

Methods:

The HPV status and the expression of Cox-2 and EGFR in the younger and older women were compared and correlated with the grading, staging neoplasm, and lymph nodal status, using Fisher test and Spearman nonparametric correlation test. Overall survival curves were drawn using Kaplan-Meier estimates and were compared using log-rank tests in the whole series of 110 patients. Multinomial logistic regression was also used.

Results and Conclusions:

The number of neoplasms with higher staging was significantly greater than those in the younger women (P= 0.04). The mortality was higher in the older group than in the younger patients (P= 0.006).

In the elderly, the presence of HPV DNA in 65% of cases, and in the absence of sexual activity, could be due to reactivation of latent HPV infection, which might be due to an impairment of host immunologic response.

The overexpression of Cox-2 in a number of cases was significantly higher in the older group than in the younger group (P= 0.032, Fisher exact test), but this immunoreactivity is not related to the staging, grading, EGFR expression, or to the presence of HPV.

The simultaneous expression of Cox-2 and EGFR had a poor prognostic significance, showing lower survival rates than cases without this immunoreactivity (P= 0.002), on univariate analysis.

On multivariate analysis, Cox-2 and EGFR immunopositivity did not reveal any correlation between these markers and prognosis probably because the number of cases considered was not particularly high.

Expression of GLUT-1 in epithelial ovarian carcinoma: correlation with tumor cell proliferation, angiogenesis, survival and ability to predict optimal cytoreduction

OBJECTIVE

GLUT-1 is involved at various steps in the processes of tumor progression. The objective of this study was to examine the relationship between GLUT-1 expression and tumor proliferation and angiogenesis in epithelial ovarian carcinoma.

MATERIALS AND METHODS

Specimens from 213 patients with epithelial ovarian carcinoma were evaluated by immunohistochemistry for GLUT-1, Ki-67, and vascular endothelial growth factor. Tumor microvessel density was assessed with CD34 immunostaining. We investigated the relationships between GLUT-1 expression and clinicopathologic characteristics, tumor angiogenesis (tumor MVD and vascular endothelial growth factor expression), and tumor proliferation (Ki-67). The effect of GLUT-1 expression on patient survival and on the volume of residual disease after cytoreduction was determined.

RESULTS

There was a significant positive correlation between expression of GLUT-1, Ki-67, and microvessel density. In univariate survival analysis, high GLUT-1 expression, high Ki-67 expression and high tumor microvessel density showed a significant impact on patient survival (p=0.0001). In multivariate analysis including patients with all tumor stages, after controlling for age, race, stage, grade, MVD, and the 3 markers (GLUT-1, Ki-67 and VEGF), only age (HR 1.5; 95% CI 1-2.3), stage (HR 3.6; 95% CI 1.8-7.5) and grade (HR 2.3; 95% CI 1.2-4.5) retained their significance as independent poor prognostic factors. Tumors simultaneously overexpressing GLUT-1 and Ki-67 were less likely to be optimally cytoreduced as compared to tumors overexpressing only one or neither of those two markers (OR: 3.8, p=0.01).

CONCLUSION

Expression of GLUT-1 correlates with tumor proliferation and microvessel density in epithelial ovarian carcinoma. In addition, patients with rapidly proliferating advanced stage tumors overexpressing GLUT-1 have a lesser chance for optimal cytoreduction.

Molecular typing of epithelial ovarian carcinomas using inflammatory markers

BACKGROUND

Ovarian epithelial carcinomas have recently been classified as slow growing type I tumors and rapidly growing highly aggressive type II tumors. The present study sought to molecularly characterize type I and II tumors using known molecular markers.

METHODS

Specimens from 213 patients with ovarian carcinoma were categorized as type I or type II, and evaluated by immunohistochemistry for the inflammatory markers glucose transporter protein-1 (Glut-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and nuclear factor kappa B. Statistical analysis was performed to investigate whether these molecular markers could distinguish between type I and type II tumors. Kaplan-Meier survival curves and COX regression analysis were used to determine the prognostic effect of these markers on survival in the 2 types of tumors.

RESULTS

Overexpression of COX-1, COX-2, iNOS, and Glut-1 was significantly higher in type II tumors (P < .05). Women with type II tumors had a poorer median survival (60 months) as compared with those with type I tumors (141 months) (P = .0001). Multivariate analysis revealed type II tumors, late stage, and age >60 years as significant predictors of poor survival. For type II tumors, median survival of patients with tumors overexpressing COX-2 was 44 compared with 85 months for those with tumors with low COX-2 expression (P = .029). Looking at both type I and II tumors, the number of markers simultaneously overexpressed in each tumor was a significant predictor of poor patient survival (P = .005).

CONCLUSIONS

The present study demonstrates that the new proposed histologic classification of ovarian epithelial carcinomas correlates with a distinct expression of inflammatory pathway proteins. High expression of these markers may explain the different biologic behavior of these 2 tumor types and provide targets for therapy.

Regulation of tumor angiogenesis by EZH2

Although VEGF-targeted therapies are showing promise, new angiogenesis targets are needed to make additional gains. Here, we show that increased Zeste homolog 2 (EZH2) expression in either tumor cells or in tumor vasculature is predictive of poor clinical outcome. The increase in endothelial EZH2 is a direct result of VEGF stimulation by a paracrine circuit that promotes angiogenesis by methylating and silencing vasohibin1 (vash1). Ezh2 silencing in the tumor-associated endothelial cells inhibited angiogenesis mediated by reactivation of VASH1, and reduced ovarian cancer growth, which is further enhanced in combination with ezh2 silencing in tumor cells. Collectively, these data support the potential for targeting ezh2 as an important therapeutic approach.

Bid mediates anti-apoptotic COX-2 induction through the IKKbeta/NFkappaB pathway due to 5-MCDE exposure

Although Bid has been considered as a cell apoptotic mediator, current studies suggest a possible role in cell survival in mouse embryonic fibroblasts (MEFs) response to low doses of anti-(+/-)-5- methylchrysene-1,2-diol-3,4-epoxide(<or=0.25 microM) (5-MCDE). We found that exposure of MEFs to 0.25 microM 5-MCDE resulted in a slight apoptotic induction, while this apoptotic response was substantially increased in the Bid knockout MEFs (Bid(-/-)), suggesting Bid-mediated anti-apoptotic function in this response. This notion was further supported by the findings that re-constitution expression of Bid into Bid(-/-) cells could inhibit the increased apoptosis. Further studies showed that Bid anti-apoptotic function was associated with its mediation of COX-2 expression, which was based on the results of the reduction of COX-2 expression in Bid(-/-) cells, restoration of low sensitivity to 5-MCDE apoptotic response by the introduction of Bid into Bid(-/-) cells and increased sensitivity of WT MEFs to 5-MCDE apoptosis by knockdown of COX-2 expression. Furthermore, Bid mediated COX-2 expression through the IKKbeta/NFkappaB pathway because the deficiency of Bid in Bid(-/-) MEFs resulted in blockade of IKK/NFkappaB activation and knockout of IKKbeta caused abrogation of COX-2 expression induced by 5-MCDE. Collectively, our results demonstrate that Bid is critical for COX-2 induction through the IKKbeta/NFkappaB pathway, which mediates its anti-apoptotic function, in cell response to low doses of 5-MCDE exposure.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Cox-2 expression in ovarian malignancies: a review of the clinical aspects

COX-2 is an inducible enzyme expressed only in response to stimuli such as mitogens, cytokines, growth factors or hormones, and is pro-inflammatory. It plays an important role in tumorigenesis. The purpose of the present report is to review the clinical aspects of COX-2 expression in ovarian malignancies. A PubMed (http://www.pubmed.gov/) search of investigations published from July 2001 until August 2008 and containing the term COX-2 in combination with ovarian malignancies was conducted. The clinical aspects of the relevant investigations were reviewed. COX-2 is expressed in ovarian tumors of low malignant potential (LMP), in epithelial ovarian carcinoma (EOC) and primary peritoneal carcinoma (PPC) and apparently plays a role in their carcinogenesis. Its expression seems to be correlated with VEGF that serves as a predictor of poor prognosis in some non-gynecologic malignancies. COX-2 expression is higher in EOC than in LMPs. The results with regard to the association between COX-2 expression and prognostic factors, response to treatment and outcome in ovarian malignancies are inconsistent. Clinical studies dealing with the effect of COX-2 inhibitors on outcome are scarce. The use of COX-2 expression in gynecological malignancies in clinical practice remains to be elucidated.

Use of nonsteroidal antiinflammatory agents and incidence of ovarian cancer in 2 large prospective cohorts

Epidemiologic data on the association between nonsteroidal antiinflammatory drugs (NSAIDs) and ovarian cancer risk have been inconsistent. The authors prospectively examined the association between regular use of aspirin and nonaspirin NSAIDs and ovarian cancer incidence among 197,486 participants of the Nurses' Health Study (NHS) and the Nurses' Health Study-II (NHS-II) over 24 and 16 years of follow-up, respectively. Information on aspirin was initially assessed in 1980 (NHS) and 1989 (NHS-II) and on nonaspirin NSAIDs and acetaminophen in 1990 (NHS) and 1989 (NHS-II) and updated throughout follow-up. The authors used Cox proportional hazards models adjusting for ovarian cancer risk factors. A total of 666 confirmed cases of epithelial ovarian cancer were identified over 2,790,986 person-years of follow-up. The hazard ratios associated with regular use of aspirin, nonaspirin NSAIDs, and acetaminophen were 1.11 (95% confidence interval (CI): 0.92, 1.33), 0.81 (95% CI: 0.64, 1.01), and 1.14 (95% CI: 0.92, 1.43), respectively. The authors did not observe a dose-response relation with increased frequency or duration of regular use of any of these medications and ovarian cancer incidence. The results did not differ substantially by tumor histology. In this large prospective study, the authors found no compelling evidence to support an association between regular use of aspirin, nonaspirin NSAIDs, or acetaminophen and ovarian cancer incidence.

Analysis of Cox-2 expression in Wilms' tumor

Cylooxygenase-2 (Cox-2) inhibitors have increasingly become therapeutic alternatives in some Cox-2-overexpressing neoplasms. As the treatment eligibility for these drugs hinges on Cox-2 expression, Cox-2 immunostaining has recently been widely examined in several malignant neoplasms. However, data on the expression of Cox-2 in Wilms' tumor (WT) are limited. In this study, we examined Cox-2 expression in 40 examples of WT to identify the prognostic impact, to evaluate the effects on tumorigenesis, and to answer the question of whether neoplasms with Cox-2 expression could benefit from treatment with specific Cox-2 inhibitors. Sections from paraffin-embedded tumor samples were immunostained by a standard ABC technique using Cox-2 mouse monoclonal antibody. As in other rare examples reported in the literature, Cox-2 immunoreactivity was analyzed and correlated with histological features and the staging of neoplasms. However, in contrast to other studies, we also evaluated the relation of Cox-2 positivity to age, sex, and survival of patients. The results of this study demonstrated that Cox-2 was ubiquitously expressed in all cases of WT and their neovasculature, independently of the type of neoplasm (tumors with a favorable or unfavorable histology), tissues which constitute the neoplasm (blastemal, mesenchymal and epithelial, heterologous or non-heterologous elements), patient age, sex, or stage of development and survival rate. Thus, Cox-2 inhibitors could be used for treating all cases of WT. Further studies, including molecular investigations, would be useful to confirm our hypotheses.

Tumor markers in ovarian carcinoma

This review analyzes in 2 ways the prognostic value of markers found in ovarian carcinomas before chemotherapy. It is known that neoangiogenesis, cyclooxygenase activity, and host responsiveness to chemotherapy can be evaluated by means of specific molecules recognized as tumor markers. However, host response as well as tumor histotype, grade of differentiation, clinical characteristics, and histopathologic characteristics must also be taken into account when selecting a treatment. Analysis must therefore focus on the molecular basis of aggressive disease, on tumor peculiarity, on the efficacy of chemotherapy, and on the host's response to the tumor. Although treatment may be more aggressive in patients with unfavorable prognostic elements, it may be modulated according to the molecular and cellular biology of the tumor and the host's response. When the tumor's molecular characterization contributes to the choice of treatment, prognostic markers may turn into predictive markers.

The prognostic importance of cyclooxygenase 2 and HER2 expression in epithelial ovarian cancer

Both cyclooxygenase 2 (COX2) and human epidermal growth factor receptor 2 (HER2, also called c-erbB-2) overexpression have been related to a worse prognosis in epithelial ovarian cancer (EOC), but the data are conflicting and the percentage of tumors with overexpression varies widely in different studies. The aim of this study was to investigate the potential prognostic value of COX2 and HER2 expression in EOC. A further purpose was to investigate a possible coexpression of the two markers, and finally, to elucidate the agreement between fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) for evaluation of the HER2 status in EOC. Immunostaining was performed for COX2/HER2 together with FISH analysis for HER2 gene amplification in 160 patients with EOC, FIGO stages IIB-IV. Follow-up was more than 10 years. COX2 overexpression was found in 20.0% of the tumors. With HER2 staining, 64.4% were scored as 0, 24.4% as 1+, 6.9% as 2+, and 4.4% as 3+. Median survival time for COX2-negative tumors was 21.6 versus 36 months for COX2-positive tumors. The longer survival for COX2 positive was significant by both univariate analysis (P= 0.015) and multivariate analysis (P= 0.025). Positive immunostaining for HER2 was associated with poor overall survival (P= 0.03). Agreement between IHC and FISH was seen in all cases (P < 0.0000001). With long-term observation, patients with negative COX2 expression had significantly shorter survival compared to patients with COX2-positive tumors. Positive HER2 expression also notified a grave prognosis, but the low rate of overexpression reduces its potential clinical application.

Ovarian epithelial cancer: a role for PGE2-synthesis and signalling in malignant transformation and progression

Background

The involvement of the cyclooxygenases (COX), in particular COX-2, is well documented for many tumours, e.g. colon, breast and prostate cancer, by both experimental and clinical studies. There are epidemiological data from subjects using NSAIDs, and experimental evidence supporting the hypothesis of prostaglandins (PGs) as regulators of tumourigenesis in the ovary. One of the end products of PG-synthesis, PGE₂, regulates several key-processes, which are characteristic for tumour growth, e.g. angiogenesis, proliferation and apoptosisis. The present study investigated the pathway for PGE₂ – synthesis and signalling in ovarian tumourigenesis by analysing specimen from normal ovaries (n = 18), benign (B) (n = 8), borderline type (BL) (n = 6) and malignant tumours (AC) (n = 22). The expression and cell-specific localization of COX-1, COX-2, microsomal prostaglandin E synthase-1 (mPGES-1) and two of the receptors for PGE₂, EP₁ and EP₂, were examined by immunoblotting (IB) and immunohistochemistry (IHC).

Results

The results are in line with earlier studies demonstrating an increase of COX-2 in AC compared to the normal ovary, B and BL tumours. Increased expressions were also observed for COX-1, mPGES-1 and EP-1 which all were significantly (p < 0.05) augmented in less differentiated AC (grades: moderately-, poorly- and undifferentiated). The increase of COX-2 was also correlated to stage (FIGO classification) with significant elevations in stages II and III. EP₁ was increased in stage III while no significant alterations were demonstrated for COX-1, mPGES-1 or EP₂ for stage. IHC revealed staining of the tumour cells, but also increase of COX-1, COX-2, mPGES-1 and EP_1–2 in the stromal compartment of AC (grades: moderately-, poorly- and undifferentiated). This observation suggests interactions between tumour cells and stromal cells (fibroblasts, immune cells), e.g. paracrine signalling mediated by growth factors, cytokines and possibly PGs.

Conclusion

The increases of COX-1, COX-2, mPGES-1 and EP_1–2 in epithelial ovarian cancer, supports the hypothesis that PGE₂-synthesis and signalling are of importance for malignant transformation and progression. The observed augmentations of COX-1, COX-2 and mPGES-1 have implications for future therapeutic strategies.

Potential predictors of chemotherapy response in ovarian cancer--how do we define chemosensitivity?

OBJECTIVE

The aim of this study was to assess whether microvessel density (measured by CD31), vascular endothelial growth factor (VEGF) or multidrug resistance (MDR1) could determine the response to chemotherapy or act as prognostic factors in ovarian cancer.

METHODS

Seventy-nine ovarian specimens were immunostained. Pearson correlation, 1-way ANOVA and chi-square were used for univariate analysis. Kaplan Meier survival curves were used, log-rank was used for univariate analysis and a Cox proportional hazards regression model was used for multivariate evaluation. Response to chemotherapy was assessed after 6 months and again after 1 year.

RESULT

Quantifying VEGF proved to be a valuable independent prognostic indicator in progression-free survival (PFS) (p<0.05) and overall survival (OS) (p<0.0001). VEGF correlated with response to chemotherapy at the 6-month interval (r=0.446, p<0.001) but failed to correlate at the 1-year interval. Increased staining with CD31 was associated with decreased PFS (p<0.01) and OS (p<0.01) in univariate but not multivariate analysis. MDR1 failed to act as a prognostic marker or as a predictor of response to chemotherapy.

CONCLUSION

VEGF correlates with response to chemotherapy at the 6-month but not the 12-month interval. What should our criteria be for determining sensitivity to chemotherapy? CD31, VEGF and MDR1 do play a role in some ovarian malignancies but other factors are likely to be involved and perhaps molecular profiling will determine which factors will be important for determining the response to chemotherapy.

Cyclooxygenase-2 Induction by Arsenite Is through a Nuclear Factor of Activated T-cell-dependent Pathway and Plays an Antiapoptotic Role in Beas-2B Cells

Arsenite is a well known metalloid human carcinogen, and epidemiological evidence has demonstrated its association with the increased incidence of lung cancer. However, the mechanism involved in its lung carcinogenic effect remains obscure. The current study demonstrated that exposure of human bronchial epithelial cells (Beas-2B) to arsenite resulted in a marked induction of cyclooxygenase (COX)-2, an important mediator for inflammation and tumor promotion. Exposure of the Beas-2B cells to arsenite also led to significant transactivation of nuclear factor of activated T-cells (NFAT), but not activator protein-1 (AP-1) and NFkappaB, suggesting that NFAT, rather than AP-1 or NFkappaB, is implicated in the responses of Beas-2B cells to arsenite exposure. Furthermore, we found that inhibition of the NFAT pathway by either chemical inhibitors, dominant negative mutants of NFAT, or NFAT3 small interference RNA resulted in the impairment of COX-2 induction and caused cell apoptosis in Beas-2B cells exposed to arsenite. Site-directed mutation of two putative NFAT binding sites between-111 to +65 in the COX-2 promoter region eliminated the COX-2 transcriptional activity induced by arsenite, confirming that those two NFAT binding sites in the COX-2 promoter region are critical for COX-2 induction by arsenite. Moreover, knockdown of COX-2 expression by COX-2-specific small interference RNA also led to an increased cell apoptosis in Beas-2B cells upon arsenite exposure. Together, our results demonstrate that COX-2 induction by arsenite is through NFAT3-dependent and AP-1- or NFkappaB-independent pathways and plays a crucial role in antagonizing arsenite-induced cell apoptosis in human bronchial epithelial Beas-2B cells.

Maspin expression and localization impact on angiogenesis and prognosis in ovarian cancer

INTRODUCTION

The goal of this study is to evaluate the relation of maspin expression and its cellular localization to markers of angiogenesis in epithelial ovarian serous carcinoma (OSC).

MATERIALS AND METHODS

We identified 118 patients with high-grade advanced stage OSC who were treated at our institution. Clinical data were collected, and immunohistochemistry (IHC) with antibodies to VEGF, CD34, COX-2, and maspin was performed on paraffin-embedded tumor blocks. CD34 immunostaining was used to determine microvessel density. The correlation between the various molecular markers was assessed using the Chi-square test. Survival analysis was computed using the Kaplan-Meier model, and various prognostic variables were compared using Cox regression analysis.

RESULTS

Maspin expression was noted in 81.4% (96/118) of tumors. Expression was localized to the nuclear compartment in 21.2% of cases, whereas 60.2% of cases showed evidence of cytoplasmic +/- nuclear expression. Tumors that exhibited nuclear maspin expression had lower VEGF and COX-2 expression than tumors with negative or cytoplasmic expression. Tumors with high nuclear maspin expression had lower mean MVD than those with low or negative expression. The median survival based on localization of maspin was 1146 days for those with negative tumors, 1803 days for those with nuclear maspin, and 637 days for those with cytoplasmic maspin (P < 0.001). In a Cox regression analysis, maspin localization was an independent prognostic factor.

CONCLUSION

Maspin expression and localization seem to play a role in ovarian cancer angiogenesis and progression. High nuclear expression was associated with reduced markers of angiogenesis and prolonged survival.