The effect of cyclooxygenase-2 expression on tumor vascularity in advanced stage ovarian serous carcinoma

Self-assembly nanoplatform of platinum (Ⅳ) prodrug for enhanced ovarian cancer therapy

Cisplatin is a metal platinum complex commonly used in the field of anti-tumor and one of the most commonly used drugs in combination chemotherapy. However, chemotherapy with Cisplatin induced overexpression of cyclooxygenase-2 (COX-2) protein in tumor cells, which could impair the therapeutic effect of chemotherapy on tumor progression. Here, we presented a novel method for the treatment of ovarian cancer with a self-assembly based nano-system. Cisplatin and tolfenamic acid were each linked to linoleic acid to give them the ability to self-assemble into nanoparticles in water. TPNPs had flexible drug ratio adjustability, homogeneous stability, and high drug loading capacity. Compared with Cisplatin, TPNPs could promote cellular uptake and tumor aggregation, co-induce enhanced apoptosis and tumor growth inhibition by inhibiting COX-2 in the mice xenograft model of human ovarian cancer, and reduce systemic toxicity. Therefore, TPNPs is a promising antitumor drug as a kind of self-assembly nano-prodrug with high drug load.

Histone Methyltransferase KMT2D Regulates H3K4 Methylation and is Involved in the Pathogenesis of Ovarian Cancer

To investigate the function of histone-lysine N-methyltransferase 2D (KMT2D) on the methylation of H3 lysine 4 (H3K4) in the progression of Ovarian cancer (OV). KMT2D, ESR1 and H3K4me expressions in surgical resected tumors and tumor adjacent tissues of OV from 198 patients were determined using immunohistochemistry (IHC). Human OV cell lines including SKOV3, HO-8910 cells and normal ovarian epithelial cell line IOSE80 were employed for in vitro experiment, and BALB/C female nude mice were used for in vivo study. qRT-PCR and Western blotting were implemented for measuring the KMT2D, ESR1, PTGS2, STAT3, VEGFR2, H3K4me and ELF3 levels. Chromatin immunoprecipitation (ChIP) analysis was used for studying the binding between ESR1 and H3K4me. Edu staining assay was executed to determine cell viability, and colony formation and cell invasion assay. The immunofluorescence method was utilized for the visualization of protein expression and distribution in cells. In this study, KMT2D, ESR1 and H3K4me were found upregulated in OV progression. Mutated H3K4me could inhibit the proliferation, colony formation and invasion ability of OV cells. Mutated H3K4me could also hinder the ESR1 in SKOV3 expressions and HO-8910 cells, which would further mediate PTGS2/STAT3/VEGF pathway. In vivo studies also demonstrated that mutated H3K4me inhibited OV progression via targeting ESR1. All the ChIP-PCR analysis indicated the moderator effect of H3K4me on ESR1. Our findings indicated that ESR1 played an important role in the OV progression. Besides, H3K4me could promote cell proliferation and inhibit apoptosis of OV cells. Meanwhile, it could also targets the ESR1 production to enhance the migration and invasion of OV cells, which was through the activation of ESR1-ELF3-PTGS2-STAT3-VEGF cascade signaling pathway.

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.

A 3D tumor microenvironment regulates cell proliferation, peritoneal growth and expression patterns

Peritoneal invasion through the mesothelial cell layer is a hallmark of ovarian cancer metastasis. Using tissue engineering technologies, we recreated an ovarian tumor microenvironment replicating this aspect of disease progression. Ovarian cancer cell-laden hydrogels were combined with mesothelial cell-layered melt electrospun written scaffolds and characterized with proliferation and transcriptomic analyses and used as intraperitoneal xenografts. Here we show increased cancer cell proliferation in these 3D co-cultures, which we validated using patient-derived cells and linked to peritoneal tumor growth in vivo. Transcriptome-wide expression analysis identified IGFBP7, PTGS2, VEGFC and FGF2 as bidirectional factors deregulated in 3D co-cultures compared to 3D mono-cultures, which we confirmed by immunohistochemistry of xenograft and patient-derived tumor tissues and correlated with overall and progression-free survival. These factors were further increased upon expression of kallikrein-related proteases. This clinically predictive model allows us to mimic the complexity and processes of the metastatic disease that may lead to therapies that protect from peritoneal invasion or delay the development of metastasis.

Tumor-linked HER2 expression: association with obesity and lipid-related microenvironment

Obesity is associated with the risk of several health disorders including certain cancers. Among obesity-related cancers, postmenopausal breast carcinoma is a well-studied one. Apart from an increase in certain types of lipids in obesity, excess adipose tissue releases many hormone-like cytokines/adipokines, which are usually pro-inflammatory in nature. Leptin is one of such adipokines and significantly linked with the intracellular signaling pathways of other growth factors such as insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), human epidermal growth factor receptor 2 (HER2). In general, HER2 is overexpressed in roughly 30% of breast carcinomas; its presence indicates aggressive tumor behavior. Conversely, HER2 has certain effects in normal conditions such as differentiation of preadipocytes, cardiovascular health and vitamin D metabolism. HER2 has no known endogenous ligand, but it may form dimers with other three members of the epidermal growth factor receptor (EGFR) family and can activate downstream signaling pathways. Furthermore, HER2 is intimately connected with several enzymes, e.g. fatty acid synthase (FASN), phosphatidylinositol 3-kinase (PI3K), AKT and mechanistic target of rapamycin (mTOR), all of which play significant regulatory roles in lipogenic pathways or lipid metabolism. In obesity-related carcinogenesis, characteristics like insulin resistance and elevated IGF-1 are commonly observed. Both IGF-1 and leptin can modulate EGFR and HER2 signaling pathways. Although clinical studies have shown mixed results, the behavior of HER2+ tumor cells including HER2 levels can be altered by several factors such as obesity, leptin and fatty acids. A precise knowledge is useful in new therapeutic approaches against HER+ tumors.

Elevated expression of protein arginine methyltransferase 5 predicts the poor prognosis of breast cancer

Protein arginine methyltransferase 5 is one of the type II protein arginine methyltransferase family members that can symmetrically dimethylate arginine residues on target proteins in both the cytoplasm and the nucleus. Protein arginine methyltransferase 5 was reported to be an oncoprotein that participates in tumor progression through both epigenetic silencing and organelle biogenesis. So far, it has been implicated in various cancers, but its expression pattern in breast cancer has not been elucidated thoroughly. We analyzed the protein arginine methyltransferase 5 expression patterns in several breast cancer samples and tissue arrays to better characterize its contribution to breast cancer. Primary breast tumors showed increased protein arginine methyltransferase 5 expression compared with adjacent normal tissues in both the fresh tissue samples and tissue arrays. Also, there was a tendency that metastatic lymph nodes demonstrated enhanced protein arginine methyltransferase 5 expression compared to primary sites. Moreover, we found a significant correlation between protein arginine methyltransferase 5 and Ki-67, with higher Ki-67 and protein arginine methyltransferase 5 expressions in primary breast tumors compared with normal breast tissues. Moreover, the Cancer Genome Atlas cohort analysis revealed that high protein arginine methyltransferase 5 messenger RNA expression was associated with an unfavorable prognosis in human epidermal growth factor receptor 2 (HER-2) positive and triple negative breast cancer patients. Finally, the roles and mechanisms of protein arginine methyltransferase 5 in the proliferation, cell cycle progression, and apoptosis of MDA-MB-231 cells were assessed using protein arginine methyltransferase 5 and shPRMT5 transfection. In conclusion, we proposed that protein arginine methyltransferase 5 is an independent prognostic biomarker for breast cancer, and targeting protein arginine methyltransferase 5 might be a promising strategy for breast cancer treatment.

COX2 and PGE2 mediate EGF-induced E-cadherin-independent human ovarian cancer cell invasion

Elevated expression of cyclooxygenase 2 (COX2 (PTGS2)) has been reported to occur in human ovarian cancer and to be associated with poor prognosis. We have previously demonstrated that COX2-derived prostaglandin E2 (PGE2) promotes human ovarian cancer cell invasion. We had also demonstrated that epidermal growth factor (EGF) induces human ovarian cancer cell invasion by downregulating the expression of E-cadherin through various signaling pathways. However, it remains unclear whether COX2 and PGE2 are involved in the EGF-induced downregulation of E-cadherin expression and cell invasion in human ovarian cancer cells. In this study, we showed that EGF treatment induces COX2 expression and PGE2 production in SKOV3 and OVCAR5 human ovarian cancer cell lines. Interestingly, COX2 is not required for the EGF-induced downregulation of E-cadherin expression. In addition, EGF treatment activates the phosphatidylinositol-3-kinase (PI3K)/Akt and cAMP response element-binding protein (CREB) signaling pathways, while only the PI3K/Akt pathway is involved in EGF-induced COX2 expression. Moreover, we also showed that EGF-induced cell invasion is attenuated by treatment with a selective COX2 inhibitor, NS-398, as well as PGE2 siRNA. This study demonstrates an important role for COX2 and its derivative, PGE2, in the mediation of the effects of EGF on human ovarian cancer cell invasion.

Design, synthesis and structure-activity relationship studies of novel and diverse cyclooxygenase-2 inhibitors as anti-inflammatory drugs

Because of the pivotal role of cyclooxygenase (COX) in the inflammatory processes, non-steroidal anti-inflammatory drugs (NSAIDs) that suppress COX activities have been used clinically for the treatment of inflammatory diseases/syndromes; however, traditional NSAIDs exhibit serious side-effects such as gastrointestinal damage and hyper sensitivity owing to their COX-1 inhibition. Also, COX-2 inhibition-derived suppressive or preventive effects against initiation/proliferation/invasion/motility/recurrence/metastasis of various cancers/tumours such as colon, gastric, skin, lung, liver, pancreas, breast, prostate, cervical and ovarian cancers are significant. In this study, design, synthesis and structure-activity relationship (SAR) of various novel {2-[(2-, 3- and/or 4-substituted)-benzoyl, (bicyclic heterocycloalkanophenyl)carbonyl or cycloalkanecarbonyl]-(5- or 6-substituted)-1H-indol-3-yl}acetic acid analogues were investigated to seek and identify various chemotypes of potent and selective COX-2 inhibitors for the treatment of inflammatory diseases, resulting in the discovery of orally potent agents in the peripheral-inflammation model rats. The SARs and physicochemical properties for the analogues are described as significant findings. For graphical abstract: see Supplementary Material. ( www.informahealthcare.com/enz ).

NF-κB and COX-2 expression in nonmalignant endometrial lesions and cancer

OBJECTIVES

To examine the immunohistochemical expression of cyclooxygenase-2 (COX-2) and nuclear factor-κB (NF-κB) in benign endometrial polyps (EPs), endometrial hyperplasia (EH), endometrial intraepithelial neoplasia (EIN), and endometrioid endometrial cancer (EC).

METHODS

The immunohistochemical expression of COX-2 and NF-κB was performed using an Aperio Scanscope XT automated system in 218 patients with endometrioid EC and 107 patients with nonmalignant endometrial lesions: 53 with benign EPs, 37 with EH, and 17 with EIN.

RESULTS

COX-2 and NF-κB p50 expression were significantly lower in EC compared with nonmalignant lesions. We observed significant decreased NF-κB p65 expression in EC vs EPs (P < .001) and EH (P = .014) as well as in EIN vs. EPs (P = .01). For patients with EC, COX-2 correlated positively with NF-κB p65 and NF-κB p50 (P < .001). Grade 3 tumors had a higher mean expression of NF-κB p65 (P = .03). NF-κB p50, NF-κB p65, and COX-2 expression had no impact on survival.

CONCLUSIONS

We conclude that COX-2 and NF-κB expression are lower in EC compared with nonmalignant endometrial lesions. COX-2 and NF-κB expression have no prognostic value in EC.

Chronic inflammation and gallbladder cancer

Gallbladder cancer (GBC) is the most common biliary tract malignancy with an extremely poor prognosis. Epidemiological data have demonstrated that chronic inflammation resulting from infection of gallbladder or gallstones predispose individuals to GBC. Recent studies have begun to elucidate molecular mechanisms underlying the development of GBC in the setting of chronic inflammation. It is possible that persistently local inflammatory reactions may contribute to the development and progression of GBC through inducing genetic alterations, and subsequent promoting survival and proliferation of mutated sells, inhibiting apoptosis, stimulating angiogenesis and metastasis. This article reviews the current understanding of the involvement of chronic inflammation in gallbladder tumorigenesis.

MiR-106a is an independent prognostic marker in patients with glioblastoma

BACKGROUND

Very little is known regarding correlation of micro RNA (miR)-106a with clinical outcomes of patients with glioblastoma multiforme (GBM). This study determined whether miR-106a could be used as an independent prognostic biomarker in those patients.

METHODS

A total of 156 GBM patients were divided into 2 cohorts. In the first cohort, matched fresh frozen and formalin-fixed paraffin-embedded (FFPE) samples were collected from 24 GBM patients, while in the second cohort, only FFPE samples were collected from 132 GBM patients. MiR-106a expression levels were examined by quantitative real-time PCR in the 2 cohorts and further validated by in situ hybridization assay in the second cohort. The correlation between miR-106a expression levels and overall survival was evaluated in the second cohort of 114 GBM patients available for follow-up by a log-rank test and a multivariate Cox proportional hazards model.

RESULTS

Our data showed a very good correlation of miR-106a or U6 expression between fresh frozen and FFPE GBM specimens, with Pearson's correlation coefficients of 0.849 and 0.823, respectively (P < .001). Their expression levels in archival FFPE samples were quite stable for at least 7 years when stored at room temperature. Multivariate analysis revealed that the expression level of miR-106a was an independent and significant predictor of overall survival in GBM patients (P = .011).

CONCLUSIONS

MiR-106a expression was relatively abundant and stable in a large cohort of archival FFPE GBM specimens and could be used as an independent prognostic biomarker in those patients. Thus, miR-106a can be used to predict prognosis and treatment response in individual GBM patients.

Overexpression of PRMT5 promotes tumor cell growth and is associated with poor disease prognosis in epithelial ovarian cancer

PRMT5 has been reported to be involved in the processes of tumor progression at various steps. The aim of this study was to examine the role of PRMT5 in epithelial ovarian cancer (EOC). In this study, PRMT5 and Ki-67 expression were examined by immunohistochemistry (IHC) in cohorts of normal, benign, and cancerous ovarian tissues. PRMT5 overexpression was observed in 83.1% (98/118) of EOCs, and it was significantly associated with serous type, poor differentiation, advanced tumor stage, lymph node invasion, presence of residual tumor, and high expression of Ki-67 (p<0.05, respectively). Moreover, overexpression of PRMT5 was an independent prognostic marker for decreased overall survival and progression-free survival in univariate survival analysis and multivariate Cox regression analysis. In ovarian cancer cell lines A2780 and SKOV3, PRMT5 knockdown by siRNA inhibited cell growth/proliferation and induced apoptosis via upregulation of E2F-1. These results suggest that overexpression of PRMT5 correlates with an aggressive malignant phenotype and may constitute a novel prognostic factor for EOC. Thus, PRMT5 may represent a clinically effective new target for therapy of ovarian cancer.

Effect of the combination of a cyclooxygenase-1 selective inhibitor and taxol on proliferation, apoptosis and angiogenesis of ovarian cancer in vivo

This study was designed to investigate the effects of a cyclooxygenase (COX)-1 inhibitor, SC-560, administered in combination with taxol, on the molecular mechanisms of antitumor efficacy in a SKOV-3 human ovarian carcinoma cell xenograft-bearing mouse model. The mice were treated with 6 mg/kg/day SC-560 by gavage twice every other day and 20 mg/kg taxol by intraperitoneal injection once a week for three weeks. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) mRNA levels of ovarian cancer were detected in the tumor tissues using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR), respectively. The index of proliferating and apoptotic cells in the tumor tissues was determined by staining for Ki-67 and using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method, respectively. On day 7 after the end of administration, the tumor volume of mice in the combination group was reduced by 55.35% compared with that of the control mice, and the difference was statistically significant (P<0.05). In the combination group, the expression of VEGF, MVD and the cell proliferation index were inhibited significantly, while the apoptotic index was notably increased (all P<0.01, compared with the control group). Our results indicate that the molecular mechanisms of the antitumor efficacy of SC-560 combined with taxol therapy may act in part by inhibiting tumor angiogenesis, reducing cell proliferation and inducing cell apoptosis.

ERLIN2 promotes breast cancer cell survival by modulating endoplasmic reticulum stress pathways

Background

Amplification of the 8p11-12 region has been found in approximately 15% of human breast cancer and is associated with poor prognosis. Previous genomic analysis has led us to identify the endoplasmic reticulum (ER) lipid raft-associated 2 (ERLIN2) gene as one of the candidate oncogenes within the 8p11-12 amplicon in human breast cancer, particularly in the luminal subtype. ERLIN2, an ER membrane protein, has recently been identified as a novel mediator of ER-associated degradation. Yet, the biological roles of ERLIN2 and molecular mechanisms by which ERLIN2 coordinates ER pathways in breast carcinogenesis remain unclear.

Methods

We established the MCF10A-ERLIN2 cell line, which stably over expresses ERLIN2 in human nontransformed mammary epithelial cells (MCF10A) using the pLenti6/V5-ERLIN2 construct. ERLIN2 over expressing cells and their respective parental cell lines were assayed for in vitro transforming phenotypes. Next, we knocked down the ERLIN2 as well as the ER stress sensor IRE1α activity in the breast cancer cell lines to characterize the biological roles and molecular basis of the ERLIN2 in carcinogenesis. Finally, immunohistochemical staining was performed to detect ERLIN2 expression in normal and cancerous human breast tissues

Results

We found that amplification of the ERLIN2 gene and over expression of the ERLIN2 protein occurs in both luminal and Her2 subtypes of breast cancer. Gain- and loss-of-function approaches demonstrated that ERLIN2 is a novel oncogenic factor associated with the ER stress response pathway. The IRE1α/XBP1 axis in the ER stress pathway modulated expression of ERLIN2 protein levels in breast cancer cells. We also showed that over expression of ERLIN2 facilitated the adaptation of breast epithelial cells to ER stress by supporting cell growth and protecting the cells from ER stress-induced cell death.

Conclusions

ERLIN2 may confer a selective growth advantage for breast cancer cells by facilitating a cytoprotective response to various cellular stresses associated with oncogenesis. The information provided here sheds new light on the mechanism of breast cancer malignancy

An intracellular targeted antibody detects EGFR as an independent prognostic factor in ovarian carcinomas

BACKGROUND

In ovarian cancer, the reported rate of EGFR expression varies between 4-70% depending on assessment method and data on patient outcome are conflicting.

METHODS

In this study we investigated EGFR expression and its prognostic value in a cohort of 121 invasive ovarian carcinomas, using a novel antibody against the intracellular domain of the receptor. We further evaluated an association between EGFR, the nuclear transporter CRM1 as well as COX-2. Furthermore, we evaluated EGFR expression in ten ovarian cancer cell lines and incubated cancer cells with Leptomycin B, a CRM1 specific inhibitor.

RESULTS

We observed a membranous and cytoplasmic EGFR expression in 36.4% and 64% of ovarian carcinomas, respectively. Membranous EGFR was an independent prognostic factor for poor overall survival in ovarian cancer patients (HR 2.7, CI 1.1-6.4, p = 0.02) which was also found in the serous subtype (HR 4.6, CI 1.6-13.4, p = 0.004). We further observed a significant association of EGFR with COX-2 and nuclear CRM1 expression (chi-square test for trends, p = 0.006 and p = 0.013, respectively). In addition, combined membranous EGFR/COX-2 expression was significantly related to unfavorable overall survival (HR 7.2, CI 2.3-22.1, p = 0.001).In cell culture, we observed a suppression of EGFR protein levels after exposure to Leptomycin B in OVCAR-3 and SKOV-3 cells.

CONCLUSIONS

Our results suggest that the EGFR/COX-2/CRM1 interaction might be involved in progression of ovarian cancer and patient prognosis. Hence, it is an interesting anti-cancer target for a combination therapy. Further studies will also be needed to investigate whether EGFR is also predictive for benefit from EGFR targeted therapies.

VEGF as a predictor for response to definitive chemoradiotherapy and COX-2 as a prognosticator for survival in esophageal squamous cell carcinoma

We investigated the patterns of pretreatment expression of the epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) by immunohistochemical staining and determined their correlation with treatment response and survival in 44 patients with esophageal squamous cell carcinoma (ESCC) treated with definitive concurrent chemoradiotherapy (CCRT). The definitive CCRT consisted of a median dose of 54 Gy (range: 40.0-68.4 Gy) and two cycles of concurrent administration of mostly 5-fluorouracil + cisplatinum. High expression of EGFR, VEGF, and COX-2 was found in 79.5%, 31.8%, and 38.6%, respectively. The Cox regression analysis for overall survival (OS) showed that both the treatment response and COX-2 expression were significant. The 3-yr OS rates of patients that achieved a complete response and those that did not were 46.7% and 5.3%, respectively (P = 0.006). The logistic regression analysis for treatment response with various parameters showed that only a high expression of VEGF was significantly associated with a complete response. Unlike other well-known studies, higher expression of VEGF was significantly correlated with a complete response to CCRT in this study. However, higher expression of COX-2 was significantly associated with shorter survival. These results suggest that VEGF might be a predictive factor for treatment response and COX-2 a prognostic factor for OS in patients with ESCC after definitive CCRT.

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.

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.

Analysis of the expression of human tumor antigens in ovarian cancer tissues

Biomarkers for early detection of cancer have great clinical diagnostic potential. Numerous reports have documented the generation of humoral immune responses that are triggered in response to changes in protein expression patterns in tumor tissues and these biomarkers are referred to as tumor associated antigens (TAAs). Using a high-throughput technology, we previously identified 65 proteins as diagnostically useful TAAs by profiling the humoral immune responses in ovarian cancer (OVCA) patients. Here we determined the expression status of some of those TAAs in tissues from OVCA patients. The protein expression patterns of 4 of those 65 antigens, namely NASP, RCAS1, Nijmegen breakage syndrome1 (NBS1) and eIF5A, along with p53 and Her2 (known molecular prognosticators) and two proteins that interact with NBS1, MRE11 and RAD50, were assessed by immunohistochemistry (IHC). NASP and RCAS1 proteins were more frequently expressed in ovarian cancer tissues than with normal ovarian tissue and serous cystadenomas and MRE11 was less frequently expressed. When evaluated simultaneously, only NASP and MRE11 remained statistically significant with sensitivity of 66% and specificity of 89%. None of these proteins' expression levels were prognostic for survival. Together, our results indicate that occurrence of humoral immune responses against some of these TAAs in OVCA patients is triggered by antigen protein overexpression.

Cyclooxygenase-2 inhibition inhibits PI3K/AKT kinase activity in epithelial ovarian cancer

Cyclooxygenase-2 (COX-2) expression contributes to tumor growth and invasion in epithelial ovarian cancer (EOC). COX-2 inhibitors exhibit important anticarcinogenic potential against EOC, but the molecular mechanisms underlying this effect and relation with PI3-kinase/AKT signaling remain the subject of intense investigations. Therefore, the role of COX-2 in EOC and its cross talk with PI3-kinase/AKT pathway were investigated using a large series of EOC tissues in a tissue micro array (TMA) format followed by in vitro and in vivo studies using EOC cell lines and NUDE mice. Clinically, COX-2 was overexpressed in 60.3% of EOC and was significantly associated with activated AKT (p < 0.0001). Cox-1 expression was seen in 59.9% but did not associate with AKT. Our in vitro data using EOC cell line showed that inhibition of COX-2 by aspirin, selective inhibitor NS398 and gene silencing by COX-2 specific siRNA impaired phosphorylation of AKT resulting decreased downstream signaling leading to cell growth inhibition and induction of apoptosis. Finally, treatment of MDAH2774 cell line xenografts with aspirin resulted in growth inhibition of tumors in NUDE mice via down-regulation of COX-2 and AKT activity. These data identify COX-2 as a potential biomarker and therapeutic target in distinct molecular subtypes of ovarian cancer.

Inflammation and cancer: how friendly is the relationship for cancer patients?

Evidence has emerged in the last two decades that at the molecular level most chronic diseases, including cancer, are caused by a dysregulated inflammatory response. The identification of transcription factors such as NF-kappaB, AP-1 and STAT3 and their gene products such as tumor necrosis factor, interleukin-1, interleukin-6, chemokines, cyclooxygenase-2, 5 lipooxygenase, matrix metalloproteases, and vascular endothelial growth factor, adhesion molecules and others have provided the molecular basis for the role of inflammation in cancer. These inflammatory pathways are activated by tobacco, stress, dietary agents, obesity, alcohol, infectious agents, irradiation, and environmental stimuli, which together account for as much as 95% of all cancers. These pathways have been implicated in transformation, survival, proliferation, invasion, angiogenesis, metastasis, chemoresistance, and radioresistance of cancer, so much so that survival and proliferation of most types of cancer stem cells themselves appear to be dependent on the activation of these inflammatory pathways. Most of this evidence, however, is from preclinical studies. Whether these pathways have any role in prevention, progression, diagnosis, prognosis, recurrence or treatment of cancer in patients, is the topic of discussion of this review. We present evidence that inhibitors of inflammatory biomarkers may have a role in both prevention and treatment of 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.

Phosphorylated epidermal growth factor receptor and cyclooxygenase-2 expression in localized non-small cell lung cancer

PURPOSE

The prognostic significance of epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) expression remains unestablished, although EGFR and COX-2 are frequently overexpressed in non-small cell lung cancer (NSCLC). Considering the importance of EGFR activation after ligand binding, however, the expression of phosphorylated EGFR (p-EGFR) may have more significance in predicting tumor aggressiveness in NSCLC than either EGFR or COX-2 expression.

PATIENTS AND METHODS

We studied the relationships between p-EGFR, EGFR, and COX-2 overexpression and examined their association with prognosis in localized NSCLC. The expression of p-EGFR, EGFR, and COX-2 was studied by immunohistochemistry in 77 surgically-resected stage I/II NSCLC cases. EGFR mutational status was determined by sequencing exons 18-21. Correlation of expression with clinical outcome and other biomarkers, including Ki-67 and microvessel density (MVD), was also examined.

RESULTS

Out of the 77 patients, EGFR overexpression was observed in 37 (48.1%), p-EGFR expression was found in 22 (28.6%), and COX-2 overexpression was seen in 45 (58.4%). Expression of p-EGFR was associated with COX-2 overexpression (P = 0.047), but not EGFR overexpression or high Ki-67 (P = 0.087 and P = 0.092, respectively). COX-2 overexpression was significantly associated with high Ki-67 (P = 0.011). Expression of p-EGFR correlated with lower disease-free survival (P = 0.045), but not overall survival. Neither EGFR nor COX-2 overexpression was associated with prognosis.

CONCLUSION

p-EGFR appears to be a better indicator for lower disease-free survival than EGFR overexpression itself in localized NSCLC. Pathways other than EGFR activation may influence COX-2 overexpression.

Matrix Metalloproteinases (MMP-2 and MMP-9) and Cyclooxygenase-2 (COX-2) Expressions in Vocal Fold Polyps

The objective of this study was to investigate the roles of matrix metalloproteinases (MMP-2, MMP-9) and cyclooxygenase-2 (COX-2) in the pathogenesis of vocal fold polyps (VFPs). In this study, 20 VFPs and 8 normal vocal fold (VF) specimens were obtained from subjects undergoing surgery. Staining intensities were semiquantitatively assessed and statistically analyzed. Significant increases were observed in the expressions of MMP-2, MMP-9, and COX-2 in stromal spindle cells (P=0.00) and vascular wall (P=0.04, P=0.00, P=0.00) of VFPs compared with normal VFs. MMP-2 expression in surface epithelium basal cells (P=0.00) of VFPs showed enhancement compared with normal vocal folds, whereas MMP-9 and COX-2 expressions showed no significant differences. Our study showed that gelatinases and COX-2 may play a role in the development of VFPs. This is the first study to document the expression of gelatinases and COX-2 in VFPs.

Cyclooxygenase-2 in cancer and angiogenesis

Tumor angiogenesis is a process where new blood vessels are formed from preexisting ones, resulting in several pathologies. Solid tumors induce angiogenesis to obtain the required nutrients and oxygen. Otherwise, tumors do not grow beyond 2 to 3 mm in diameter. Cyclooxygenase-2, an inducible enzyme important in inflammation, catalyzes the production of prostanoids from arachidonic acid. Cyclooxygenase-2 plays an important role in several cancer types, including colorectal, gastric, prostate, breast, lung, and endometrial cancer. Besides, cyclooxygenase-2 has been implicated in the progression and angiogenesis of cancers. Cyclooxygenase-2 inhibitors have been used to block angiogenesis and tumor proliferation. In this review, the recent studies related to the role of cyclooxygenase-2 in several cancer types and tumor-induced angiogenesis were compiled.

15-Lipoxygenase-2 is differentially expressed in normal and neoplastic ovary

Ovarian cancer is a major cause of lethality from gynecological malignancies, and there is a lack of reliable and specific serum markers for this disease. Eicosanoid-related enzymes have previously been implicated in the pathogenesis of various types of cancer, but little is known about the relevance of lipoxygenase isoforms in ovarian cancer and the results on cyclooxygenases are conflicting. For this study, we quantified the expression of eicosanoid-related enzymes (cyclooxygenase-1 and cyclooxygenase-2, 15-lipoxygenase-1 and lipoxygenase-2, 5-lipoxygenase) in normal and malignant human ovarian tissue by real-time polymerase chain reaction and found a 22-fold elevated expression of 15-lipoxygenase-2 in malignant specimens when compared with normal ovarian tissue (P=0.001). In ovarian carcinoma metastases, expression of the enzyme was also augmented (20-fold upregulation, P=0.004). For 15-lipoxygenase-1 and cyclooxygenase-2, we did not observe differential expression, but there was a trend for increased steady-state concentrations of cyclooxygenase-1 (P=0.1 for ovarian carcinoma, P=0.011 for metastases) and 5-lipoxygenase (P=0.1 for ovarian carcinoma, P=0.018 for metastases, respectively). These data indicate that expression of 15-lipoxygenase-2 mRNA is strongly augmented during ovarian carcinogenesis and that the enzyme may constitute a suitable candidate as a tumor marker.

Clinical implications of the ErbB/epidermal growth factor (EGF) receptor family and its ligands in ovarian cancer

The ERBB or EGF receptor (EGFR) proto-oncogene family, which consists of four structurally-related transmembrane receptors (i.e., EGFR, ErbB2, ErbB3, and ErbB4), plays an etiological role in the molecular pathogenesis of cancer and is a key therapeutic target in many types of cancer, including ovarian cancer. These ErbB/EGF receptor tyrosine kinases play important physiologic roles in cell proliferation, survival, adhesion, motility, invasion, and angiogenesis. It is, therefore, not surprising that gene amplification, genetic mutation, and altered transcription/translation result in aberrant ErbB/EGF receptor expression and/or signal transduction, contributing to the development of malignant transformation. Clinically, the diagnostic, prognostic, and theragnostic significance of any single ErbB receptor and/or ErbB ligand is controversial, but generally, ErbB receptor overexpression has been correlated with poor prognosis and decreased therapeutic responsiveness in ovarian cancer patients. Thus, anticancer agents targeting ErbB/EGF receptors hold great promise for personalized cancer treatment. Yet, challenges remain in designing prospective clinical trials to assess the clinical utility of ErbB receptors and their ligands to diagnose cancer; to predict progression-free and overall survival, therapeutic responsiveness, and disease recurrence; and to monitor treatment responsiveness. Here, we review the tissue expression and serum biomarker studies that have evaluated the diagnostic, prognostic, and theragnostic utility of ErbB/EGF receptors, their circulating soluble isoforms (sEGFR/sErbBs), and their cognate ligands in ovarian cancer patients.

The prognostic significance of COX-2 and survivin expression in ovarian cancer

We investigated the prognostic significance of cyclooxygenase-2 (COX-2) and survivin in ovarian carcinoma. Imprint smears were obtained from 100 ovarian carcinoma specimens and were studied immunocytochemically for the expression of COX-2 and survivin. The results were correlated with several clinicopathological parameters, including 5-year survival. Increased COX-2 staining pattern correlated with a non-mucinous histological type (p=0.008), increased stage (p<0.0001), high histological grade (p<0.0001), and reduced survival rates (p<0.00001). Survivin expression was strongly associated with increased stage (p<0.0001), increased histological grade (p<0.0001), and reduced survival (p<0.00001). Elevated survivin expression also correlated significantly with pre-menopausal status (p=0.033). In addition, COX-2 and survivin staining patterns correlated strongly with one another (p<0.0001). However, on multivariate analysis, an independent prognostic value was found only for tumor stage and grade. The findings of our study indicate that the increased expression of COX-2 and survivin in ovarian cancer is associated with one another and with several adverse clinicopathologic parameters, including reduced survival, thus suggesting a role of these molecules in disease progression. Further investigations of the exact prognostic and therapeutic implications of COX-2 and survivin expression are strongly warranted.

Expression and biological role of the prostaglandin D synthase/SOX9 pathway in human ovarian cancer cells

New therapeutic strategies for ovarian cancer include the identification of involved signaling pathways that could potentially serve as a source of biomarkers for early stages of the disease. In this study, we show that the embryonic male prostaglandin D synthase (Pgds)/SOX9 pathway is expressed at both the RNA and protein levels in different types of human ovarian tumors, pointing to Pgds and SOX9 as possible diagnostic markers for ovarian carcinomas. Using ovarian cancer cell lines, we found, first, that components of the Pgds/SOX9 pathway are expressed in these cells, and second, that treatment of these cells with prostaglandin D2 (PGD2) can inhibit their growth via its DP1 receptor and induce apoptosis. Finally, using siRNA and overexpression strategies, we demonstrate that SOX9 expression is induced by PDG2 and is responsible for PDG2-mediated growth inhibition. Accordingly, as stimulating the PGD2/DP1 signal transduction pathway upregulates SOX9 expression, either activators of this pathway or DP1 agonists may be useful as new therapeutic agents.

Immunohistochemical Expression of Cyclooxygenase-2 in Canine Ovarian Carcinomas

Ovarian tumours among domestic animals are frequently encountered in bitch. Cyclooxygenase-2 (COX-2) expression has been evaluated in different kind of canine primary epithelial neoplasms. Eleven canine ovarian carcinomas and two normal samples were evaluated immunohistochemically for COX-2 expression. Nine of 11 carcinoma samples (81%) expressed COX-2 enzyme isoform. The immunoreactivity was intracytoplasmically recorded and the intensity ranged from faint to strong. Our results show that COX-2 is expressed in canine ovarian carcinoma, suggesting a potential role of COX-2 in canine ovarian carcinogenesis.

Advance of the relationship between esophageal cancer and cyclooxygenase-2

Cyclooxygenase (COX) is a rate-limiting enzyme in the arachidonate metabolism. COX-2, as one of the isoenzymes of COX, is responsible for the pathogenesis, development, metastasis and prognosis of carcinoma through various mechanisms. Esophageal cancer is one of the common cancers with high incidence and high mortality. It is reported that COX-2 plays important roles in it, through xenobiotic metabolism, inhibiting apoptosis, development of inflammation-stimulated hyperplasia and metaplasia, suppressing host immune responses, inducing angiogenesis and promoting infiltration and metastasis. Recently, some trials demonstrated that selective COX-2 inhibitors can inhibit COX-2 to prevent carcinogenesis. In this article, we reviewed the roles of COX-2 in the carcinogenesis and analyzed COX-2 inhibitors for the chemoprevention of esophageal cancer.

Cell proliferation activity unrelated to COX-2 expression in ovarian tumors

The objective of this study was to assess the expression of Cyclooxygenase-2 (COX-2) and cell proliferation activity (Ki67 expression) in benign, borderline, and malignant serous and mucinous ovarian tumors. Expression of COX-2 and Ki67 proteins were evaluated by immunohistochemistry, in paraffin-embedded sections of ovarian epithelial tumors. The study included 113 serous (67 benign, 15 borderline, and 31 malignant) and 85 mucinous (48 benign, 28 borderline, and 9 malignant) tumors, removed from women who underwent laparotomy between January 1997 and December 2003. From benign to malignant tumors, there was a progressive positive trend in COX-2 expression in both serous and mucinous tumors, more evident in mucinous ones (P < 0.001). Comparing histologic types, COX-2 expression was more prominent in serous than in mucinous benign tumors (P < 0.01), but this difference was not significant in the borderline (P= 0.11) or malignant categories (P= 0.71). There was a progressive Ki67 positivity in line with the tumor histologic gradient for both serous (P < 0.01) and mucinous lesions (P < 0.01), but this increasing expression did not correlate with COX-2 expression in the present series (P= 0.78). There was a higher COX-2 expression in serous ovarian adenomas than in mucinous ones. COX-2 positivity increases in line with the morphologic gradient, from benign to malignant in both histologic types, but it was more prominent in mucinous lesions, pointing to different oncogenic pathways related to different histologic types. A correlation between the expression of COX-2 and Ki67 was not found, suggesting that COX-2 may be required for carcinogenesis, but this pathway is not responsible for cell proliferation in ovarian tumors.

Increased expression of hypoxia-inducible factor 1alpha in type I and type II endometrial carcinomas

Hypoxia-inducible factor 1alpha (HIF-1alpha) is a nuclear protein that is upregulated in many tumors and triggers biologic events intimately associated with aggressive tumor behavior. The aim of this study was to analyze the expression of HIF-1alpha, vascular endothelial growth factor (VEGF), Ki-67 and p53 in type I and type II endometrial adenocarcinoma. In total, 149 patients diagnosed with endometrial adenocarcinoma in our institute from 1995 to 2001 were included in this study, of which 108 were type I and 41 were type II endometrial adenocarcinoma. Patient demographics, clinical and pathological data were reviewed. Tissue microarrays were prepared from the paraffin blocks and immunohistochemistry was performed for antibodies against HIF-1alpha, VEGF, Ki-67 and p53. High expression of HIF-1alpha, VEGF, Ki-67 and p53 were significantly more frequent in type II than type I endometrial adenocarcinoma (P<0.001). HIF-1alpha expression was highly correlated with VEGF expression in the tumor cells (P=0.001). In type I endometrial adenocarcinoma, high expression of HIF-1alpha showed a significant correlation with higher grade of the tumor, depth of myometrial invasion, adnexal invasion and clinical stage. A similar correlation was not observed in type II endometrial adenocarcinoma. Surgical stage was the only independent prognostic marker for survival. In conclusion, high expression of HIF-1alpha is more frequent in type II than in type I endometrial adenocarcinoma. In type I endometrial adenocarcinoma, HIF-1alpha expression correlates with morphologic features of aggressiveness. In type II endometrial adenocarcinoma, there is no correlation between HIF-1alpha expression and these features. Thus, HIF-1alpha may play an important role in endometrial adenocarcinoma progression, particularly in type I endometrial adenocarcinoma. Additional investigations of HIF-1alpha as a biomarker of aggressive potential and as a novel target for therapeutics in endometrial adenocarcinoma are warranted.

Overexpression of cyclooxygenase-2 correlates with tumor angiogenesis in endometrial carcinoma

The inducible enzyme cyclooxygenase-2 (COX-2) is an important mediator of angiogenesis and tumor growth. Several reports have indicated that vascular endothelial growth factor (VEGF)-positive tumors are associated with an increased amount of COX-2 protein. This study evaluated the significance of COX-2 in 34 patients with endometrial carcinoma and its relationship to angiogenesis. Immunohistochemical expression of COX-2 and VEGF was analyzed on paraffin-embedded tissue sections. Microvessel density (MVD) of endometrial carcinoma was also determined with anti-CD(34) as the label. COX-2 messenger RNA (mRNA) was analyzed by reverse transcription-polymerase chain reaction. The expression rate of COX-2 in 34 cases was 64.7% but not in control endometrium. COX-2 mRNA was higher in tumor specimens than in normal tissues. The level of COX-2 expression was higher in grade 2 tumors than in grade 3 tumors (P < 0.05). MVD was higher in COX-2-positive and VEGF-positive cases than in COX-2-negative and VEGF-negative cases (P < 0.05). The expression of COX-2 was positively correlated with the expression of VEGF and MVD (P < 0.05 and P < 0.01, respectively). The present findings suggest that overexpression of COX-2 may induce the expression of VEGF, increase angiogenesis, and enhance tumor growth.

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.

Expression of cyclooxygenase-2 and inducible nitric oxide synthase in ovarian surface epithelial carcinomas: is there any correlation with angiogenesis or clinicopathologic parameters?

Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) products have been implicated in the regulation of immune system, tumor cell apoptosis, and angiogenesis in many human tumors. In this study, we investigated the expression of COX-2 and iNOS in ovarian carcinomas by immunohistochemistry and correlated the results with other prognostic parameters. Specimens from 100 ovarian carcinomas were studied by immunohistochemistry for COX-2 and iNOS expression, and angiogenesis microvessel density (MVD) was evaluated by CD34-stained microvessels. High COX-2 expression was observed in 85% of carcinomas. No correlation was found between COX-2 expression and clinicopathologic variables. Patients with high COX-2-expressed tumors had shorter overall survival, but it is not statistically significant. Expression of iNOS in serous and low-grade carcinomas was significantly higher than that in nonserous and high-grade carcinomas (P < 0.05). There was a positive correlation between COX-2 and iNOS expression (P= 0.009). No correlation of COX-2 and iNOS expression with MVD was found. Expression of iNOS showed no effect on survival of the patients. We found that iNOS expression might act in the first steps of carcinogenesis, whereas COX-2 expression was seen in more advanced tumors. Shorter overall survival of patients with high COX-2 expression might indicate new targets for therapy.

Expression of cyclooxygenase-2 related to angiogenesis in uterine cervical cancers

Angiogenesis is essential for development, growth and advancement of solid tumors. Cyclooxygenase (COX)-2 is recognized as an angiogenic factor in various tumors. This prompted us to study the clinical implications of COX-2 expression related to angiogenesis in uterine cervical cancers. There was a significant correlation between microvessel counts and COX-2 levels in uterine cervical cancers. COX-2 localized in the cancer cells, but not in the stromal cells of uterine cervical cancer tissues. COX-2 levels increased with advancement, and the prognosis of the 30 patients with high COX-2 expression in uterine cervical cancers was poor (60%), while the 24-month survival rate of the other 30 patients with low COX-2 expression was 90%. Furthermore, COX-2 levels significantly correlated with VEGF levels in uterine cervical cancers. VEGF associated with COX-2 might work on angiogenesis in advancement. Therefore, long-term administration of COX-2 inhibitors might be effective on the suppression of regrowth or recurrence after intensive treatment for advanced uterine cervical cancers.

Increasing cyclooxygenase-2 (cox-2) gene expression in the progression of Barrett's esophagus to adenocarcinoma correlates with that of Bcl-2

Previous studies from our laboratory and others have suggested that increased expression of cox-2 is important in the genesis of esophageal adenocarcinoma. In vitro studies suggest that cox-2 regulates expression of the anti-apoptotic protein bcl-2, thus possibly accounting for reduced apoptosis in carcinogenesis. The aim of this study was to investigate the relationship of these 2 genes in the development of Barrett's-associated adenocarcinoma. Histologic sections from endoscopic biopsies or esophagectomy specimens were classified as non-dysplastic Barrett's (n = 30), intraepithelial neoplasia (n = 12) and adenocarcinoma (n = 48). The desired tissue was isolated by laser capture microdissection and expression levels of cox-2 and bcl-2 were measured by quantitative real-time PCR (Taqman). Gene expression levels were compared to samples of the distal esophageal squamous epithelium (n = 55) and reflux-esophagitis (n = 25), without Barrett's or cancer. Expression of both bcl-2 and cox-2 were increased in non-dysplastic Barrett's (p = 0.0077, p = 0.0037), intraepithelial neoplasia (p = 0.0053, p = 0.0220) and adenocarcinoma (p < 0.0001, p < 0.0001) compared to squamous epithelium or reflux-esophagitis. Furthermore, there is a significant correlation between these two genes, especially in carcinoma (p < 0.0001).

Cyclo-oxygenase-2 (Cox-2) expression and resistance to platinum versus platinum/paclitaxel containing chemotherapy in advanced ovarian cancer

Background

Cyclo-oxygenase-2 (COX-2), the key enzyme in the conversion of arachidonic acid to prostaglandins, is involved in critical steps of tumor onset and progression, and is a strong predictor of chemotherapy resistance and poor outcome in advanced ovarian cancer. To our knowledge, no data has been reported until now about the association between COX-2 status and response to different chemotherapy regimens.

Methods

A retrospective study was performed to investigate the association of COX-2 with outcome and response to platinum versus platinum/paclitaxel in 68 primary ovarian cancer. COX-2 immunoreaction was performed on paraffin-embedded sections by using rabbit polyclonal antiserum against COX-2.

Results

In the overall series, COX-2 positivity was found in a statistically significant higher percentage of not responding cases than in patients responding to chemotherapy (n = 15/21; 71.4% versus n = 17/47; 36.1%; p value = 0.0072). A higher percentage of COX-2 positivity was found in patients unresponsive (n = 11/13; 84.6%) versus patients responsive to platinum-based chemotherapy (n = 9/26; 34.6%). In cases administered platinum/paclitaxel, COX-2 positivity was found in 4 out of 8 (50%) of un responsive versus 8 out of 21 (38.1%) of responsive cases. Logistic regression analysis of parameters likely to affect response to treatment resulted in a p value = 0.17 for the interaction COX-2/type of treatment.

Conclusion

Although these findings need to be confirmed in a larger series, our study suggests a possible indication that there is a difference in the influence of COX-2 on response depending on treatment regimen.

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.

The racial disparity in outcomes in endometrial cancer: could this be explained on a molecular level?

OBJECTIVE

The racial disparities among patients with endometrial carcinoma have been previously reported. The objective of this study is to analyze and compare the molecular profiles in endometrial cancer in Caucasian and African American patients using a number of known molecular markers.

MATERIALS AND METHODS

147 patients diagnosed with endometrial cancer between 1995 and 2001 were included in the study. Patients' demographics, clinical and pathological data were reviewed. Immunohistochemical staining for p53, VEGF, Ki-67 and HIF-1alpha was performed on tissue micro array sections. Tumors' expression of p53, VEGF, Ki-67, and HIF-1alpha was compared based on ethnicity and tumor type (Type I = endometrioid carcinomas and Type II = non-endometrioid carcinomas). Spearman's correlation and Fisher's Exact Tests were used for statistical analysis and Kaplan-Meier, log-rank and Cox regression were used for survival analysis.

RESULTS

97 patients were Caucasian and 50 patients were African American. The mean age was 62 (33-91) years for Caucasian patients and 63.5 (24-89) years for the African American patients. African American patients had more Type II carcinoma than Caucasian patients (P = 0.055). High p53 expression was statistically significant among the African American patients (49% vs. 30%, P = 0.035) versus Caucasian patients. There was no significant difference demonstrated when comparing the VEGF, Ki-67, and HIF-1alpha expression between the racial groups. Survival analysis showed a trend toward a shorter survival in the African American patients compared to the Caucasian patients; median survival 62 versus 77 months (P = 0.061). On the other hand, we did not find a significant difference in survival by ethnicity when we adjusted for tumor histology.

CONCLUSION

While African American patients with endometrial cancer seem to show a trend toward a shorter survival, this seems to be mainly due to the fact that they have a higher proportion of Type II tumors. The molecular profiles for p53, Ki-67, VEGF and HIF-1alpha expression of histologically matched tumors were similar between the two ethnic groups.

Diagnostic markers of ovarian cancer by high-throughput antigen cloning and detection on arrays

A noninvasive screening test would significantly facilitate early detection of epithelial ovarian cancer. This study used a combination of high-throughput selection and array-based serologic detection of many antigens indicative of the presence of cancer, thereby using the immune system as a biosensor. This high-throughput selection involved biopanning of an ovarian cancer phage display library using serum immunoglobulins from an ovarian cancer patient as bait. Protein macroarrays containing 480 of these selected antigen clones revealed 65 clones that interacted with immunoglobulins in sera from 32 ovarian cancer patients but not with sera from 25 healthy women or 14 patients having other benign or malignant gynecologic diseases. Sequence analysis data of these 65 clones revealed 62 different antigens. Among the markers, we identified some known antigens, including RCAS1, signal recognition protein-19, AHNAK-related sequence, nuclear autoantogenic sperm protein, Nijmegen breakage syndrome 1 (Nibrin), ribosomal protein L4, Homo sapiens KIAA0419 gene product, eukaryotic initiation factor 5A, and casein kinase II, as well as many previously uncharacterized antigenic gene products. Using these 65 antigens on protein microarrays, we trained neural networks on two-color fluorescent detection of serum IgG binding and found an average sensitivity and specificity of 55% and 98%, respectively. In addition, the top 6 of the most specific clones resulted in an average sensitivity and specificity of 32% and 94%, respectively. This global approach to antigenic profiling, epitomics, has applications to cancer and autoimmune diseases for diagnostic and therapeutic studies. Further work with larger panels of antigens should provide a comprehensive set of markers with sufficient sensitivity and specificity suitable for clinical testing in high-risk populations.

Expression of cyclooxygenase-2 in epithelial ovarian tumors and its relation to vascular endothelial growth factor and p53 expression

The purpose of this study was to evaluate cyclooxygenase-2 (COX-2) expression in epithelial ovarian tumors and its correlation with vascular endothelial growth factor (VEGF) and p53 expression. Immunohistochemical studies with anti-COX-2, anti-VEGF, and anti-p53 antibodies were carried out in 54 malignant and 23 borderline epithelial ovarian tumors. Elevated COX-2 expression was detected in 77.8% of ovarian carcinomas, which was significantly higher than that of borderline tumors (26.1%) (P < 0.001). In ovarian carcinomas, there was no significant correlation between COX-2 expression and other clinicopathologic features. Elevated VEGF expression was detected in 74.1% of ovarian carcinomas, and p53 expression was found in 64.8% of ovarian carcinomas. COX-2 expression was statistically correlated with elevated VEGF expression (P < 0.001) and p53 positivity (P < 0.05). On a univariate analysis, FIGO stage (P < 0.0001), histologic type (P= 0.0104), and COX-2 expression (P= 0.0135) were significant prognostic factors for overall survival. In a multivariate analysis, FIGO stage (P < 0.0001) was the only independent prognostic factor for poor survival. These findings suggest that COX-2 may play a role in the progression of epithelial ovarian tumors and that COX-2 expression may contribute to ovarian tumor angiogenesis by stimulating VEGF expression. p53 may be responsible for the regulation of COX-2 expression.

Cytoplasmic HuR expression correlates with epithelial cancer cell but not with stromal cell cyclooxygenase-2 expression in mucinous ovarian carcinoma

Cyclooxygenase-2 (COX-2) expression has been found to associate with poor prognosis in several types of carcinomas. HuR is an mRNA stability protein and it regulates the expression of COX-2.

OBJECTIVES AND METHODS

We analyzed the expression of COX-2 and HuR in 64 mucinous ovarian carcinoma specimens by immunohistochemistry.

RESULTS

In mucinous tumors, high COX-2 protein expression was found in epithelial cancer cells in 39% (22/56) and in stromal cells in 24% (13/55) of the specimens. The expression of COX-2 in cancer cells correlated with high grade (P = 0.0285), but stromal COX-2 expression had no correlation with any clinical parameter tested. Cytoplasmic HuR protein expression was observed in cancer cells in 47% (27/57) and in stromal cells in 7% (4/56) of the mucinous tumors, and it correlated with COX-2 expression in the cancer cells (P = 0.0162) but not in the stroma.

CONCLUSION

Our results support the hypothesis that cytoplasmic HuR is connected to COX-2 expression in ovarian carcinoma, but that its role is restricted to the transformed epithelial cancer cells.

The impact of c-kit and ki-67 expression on patients prognosis in advanced ovarian serous carcinoma

The transmembrane-tyrosine-kinase receptor, c-kit, is involved in cell differentiation and has been found to be expressed in normal human cell types and solid tumors. This study was designed to investigate the effects of c-kit expression on: 1) tumor proliferation and apoptosis, and 2) survival in patients with high-grade advanced stage ovarian serous carcinoma (OSC). We identified 118 patients with high-grade advanced stage OSC from our files. Clinical data, including demographics and overall survival, were collected. Immunohistochemical panel consisting of c-kit, ki-67, p53, and bcl-2 was performed. C-kit was categorized as positive if any cytoplasmic or membranous staining pattern was identified. Correlation between c-kit expression and the other markers was performed. Survival analysis was performed using COX proportional hazards regression and Kaplan-Meier test. Of 118 cases, 25 (21.2%) expressed c-kit. Of 93 c-kit-negative tumors, 87.1% had a high proliferation index. High p53 and bcl-2 expression was identified in 96 (81.4%) and 59 (50%) cases respectively. No significant statistical correlation was identified between c-kit and apoptosis markers. Tumors lacking c-kit expression showed a trend toward having high proliferation index, but this did not achieve statistical significance (p = 0.07). Of the seven variables included in the multivariate survival analysis, only c-kit (odds ratio, 2.12; 95% confidence interval, 08-4.17; p = 0.02) and ki-67 (odds ratio, 1.9; 95% confidence interval, 1.1-3.1; p = 0.03) showed an independent statistically significant impact on survival. High-grade advanced stage OSC lacking c-kit expression correlates with poor outcome. Interestingly, cases lacking c-kit expression also showed a trend to have high proliferation index.

Correlation of epidermal growth factor receptor expression with tumor microdensity vessels and with vascular endothelial growth factor expression in ovarian carcinoma

We analyzed in advanced ovarian serous G3 carcinoma the correlation between epidermal growth factor receptor (EGFR) overexpression and tumor angiogenesis and their relation with clinical outcome. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were statistically correlated with disease-free interval and death from disease both in univariate and multivariate analyses while EGFR expression was not correlated with clinical outcome. MVD was significantly associated with progression of disease during chemotherapy while VEGF and EGFR expression were not correlated with responsiveness to chemotherapy (Fisher's exact test). VEGF expression was correlated with MVD (Fisher's exact test). EGFR showed a trend to correlation with MVD. Further studies focusing on the use of angiogenesis inhibitors in addition to EGFR inhibitors on ovarian carcinoma cells may produce therapeutic strategies in the selection of tailored therapies in ovarian cancer patients.

Prostaglandin E2 production in ovarian cancer cell lines is regulated by cyclooxygenase-1, not cyclooxygenase-2

The significance of cyclooxygenase-2 (COX-2) expression in ovarian cancer has been discussed. In this study, we found increased expression of COX-1 mRNA and protein in three out of 10 ovarian cancer cell lines. Prostaglandin E 2 (PGE2) production was elevated in these three cell lines, but not in other seven cell lines. COX-2 protein was not detected in any of the cell lines. Cytosolic prostaglandin E synthase (cPGES) mRNA and protein were detected in all 10 cell lines. Membrane-associated PGES-1 (mPGES-1) was detected in some of the ovarian cell lines, but its presence did not correspond with PGE2 production. In contrast, mPGES-2 mRNA and protein were detected in all 10 cell lines. A nonselective COX inhibitor (indometacin) and a selective COX-1 inhibitor (SC-560) strongly inhibited PGE2 production by the three cell lines, while selective COX-2 inhibitors (NS-398 and rofecoxib) did not inhibit PGE2 production. In addition, increased expression of COX-1, not COX-2 protein was observed in the mass of ovarian cancer tissues from 22 patients when compared with that in normal tissue. These findings suggest that COX-1 might be a major enzyme regulating PGE2 production in ovarian cancer cells.