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

Expression of cyclooxygenase-2 (COX-2) in epithelial ovarian cancers in an Indigenous African population of Kano, Nigeria

The high case-fatality of epithelial ovarian cancer (EOC) stems from the absence of recognisable premalignant lesion, lack of effective screening, advanced stage at presentation, high recurrence and COX-2 over-expression. Expression of COX-2 in EOCs is associated with unfavorable survival outcomes. In Nigeria, younger age affectation, rising incidence and poor survival outcomes of EOC provide the driving forces for researchers in terms of screening, prevention and targeted therapy.

Methods

All the 52 EOC cases over a 5-year period were included, but only 48 formalin-fixed paraffin-embedded tissue blocks were sectioned and stained with COX-2 antibody. COX-2 expression was scored for distribution (no cells = 0, 1%-10% = 1, 11%-50% = 2, 51%-80% = 3, 81%-100% = 4) and intensity (no stain = 0; weak = 1; moderate = 2, strong = 3). The immunoreactive score (IRS) is a product of intensity (I) and distribution (D) as: 9-12 strongly +, 5-8 moderately +, 1-4 weakly + and 0 negative. Over-expression of COX-2 is an IRS of 5-12. Outcomes were statistically evaluated with clinicopathological data.

Results

EOC cases have a mean age of 50.0 years, and peaked in the 6th decade. High-grade serous carcinoma (HGSC) accounted for the majority (50%), followed by low-grade serous carcinoma and mucinous carcinomas each at 17.3%. High-grade carcinomas accounted for 61.5% of cases. Over-expression of COX-2 was observed in 52.1% of the cases with significant associations between COX-2 expression and high-grade EOC, type II EOC or HGSC but not with the other histological sub-type or age.

Conclusion

More than one-third of EOCs occurred ≤50 years and more than half of EOCs over-expressed COX-2. There were significant statistical associations between COX-2 over-expression and grade, type II tumours or HGSC indicating that it may influence the outcomes of EOC with possible variation in tumour type and grade.

COX-2 expression in ovarian cancer: an updated meta-analysis

The prognostic role of COX-2 expression in ovarian cancer patients has been studied for years, while results remain controversial. Thus we performed a meta-analysis to evaluate the prognostic impact of COX-2 expression on survival of ovarian cancer patients. The databases PubMed, Embase and CNKI were searched. Summary hazard ratio (HR) and 95% confidence intervals (CIs) were calculated to analyze the correlations between COX-2 expression and overall survival (OS), and disease-free survival (DFS). A total of 1,867 patients from 18 studies were enrolled in the final analysis. The results showed that patients with higher COX-2 expression had a poor OS (HR: 1.48; 95% CI: 1.19-1.85) and DFS (HR: 1.81, 95% CI: 1.28-2.55). Subgroup analysis showed that there had significant associations between COX-2 expression and survival rate in most of the subgroups. Furthermore, there were significant associations between COX-2 expression and several clinical parameters such as FIGO stage, histological type and age. These results showed the patients with higher COX-2 expression had a significantly poorer survival rate, COX-2 expression had the potential to be a prognostic marker of ovarian cancer.

Prognostic value of HER-2/neu expression in epithelial ovarian cancer: a systematic review and meta-analysis

This study aimed to conduct a meta-analysis to investigate the association between human epidermal growth factor receptor 2 (HER-2/neu) expression and survival in patients with epithelial ovarian cancer (EOC). HER-2/neu is one of the most frequently studied molecular biological parameters in EOC, but its prognostic impact has not been fully assessed. PubMed and Embase were searched for studies that reported HER-2/neu expression and survival in patients with EOC. The primary outcome was overall survival (OS), and the secondary outcome was progression-free survival (PFS). Hazard ratios (HRs) with 95% confidence interval (CI) were determined using Mantel-Haenszel random-effects model. Publication bias was investigated using funnel plots and Egger's test. A total of 56 studies (N=7212) were included in the analysis. The results showed that patients possessing HER-2/neu expression had significant disadvantages in OS (HR = 1.41; 95%CI, 1.31 to 1.51; P < 0.001) and PFS (HR = 1.38; 95% CI, 1.23-1.56; P < 0.001). The trim-and-fill method, Copas model, and subgroup analyses stratified by the study characteristics confirmed the robustness of the results. The present study findings provided further indication that HER-2/neu expression in patients with EOC has an adverse impact on OS and PFS.

Hypoxia inducible factor down-regulation, cancer and cancer stem cells (CSCs): ongoing success stories

In cancers, hypoxia inducible factor 1 (HIF-1) is an over-expressed transcription factor, which regulates a large set of genes involved in tumour vascularization, metastases, and cancer stem cells (CSCs) formation and self-renewal. This protein has been identified as a relevant target in oncology and several HIF-1 modulators are now marketed or in advanced clinical trials. The purpose of this review is to summarize the advances in the understanding of its regulation and its inhibition, from the medicinal chemist point of view. To this end, we selected in the recent literature relevant examples of "hit" compounds, including small-sized organic molecules, pseudopeptides and nano-drugs, exhibiting in vitro and/or in vivo both anti-HIF-1 and anti-tumour activities. Whenever possible, a particular emphasis has been dedicated to compounds that selectively target CSCs.

Development and Validation of a Histological Method to Measure Microvessel Density in Whole-Slide Images of Cancer Tissue

Despite all efforts made to develop predictive biomarkers for antiangiogenic therapies, no unambiguous markers have been identified so far. This is due to among others the lack of standardized tests. This study presents an improved microvessel density quantification method in tumor tissue based on stereological principles and using whole-slide images. Vessels in tissue sections of different cancer types were stained for CD31 by an automated and validated immunohistochemical staining method. The stained slides were digitized with a digital slide scanner. Systematic, uniform, random sampling of the regions of interest on the whole-slide images was performed semi-automatically with the previously published applications AutoTag and AutoSnap. Subsequently, an unbiased counting grid was combined with the images generated with these scripts. Up to six independent observers counted microvessels in up to four cancer types: colorectal carcinoma, glioblastoma multiforme, ovarian carcinoma and renal cell carcinoma. At first, inter-observer variability was found to be unacceptable. However, after a series of consensus training sessions and interim statistical analysis, counting rules were modified and inter-observer concordance improved considerably. Every CD31-positive object was counted, with exclusion of suspected CD31-positive monocytes, macrophages and tumor cells. Furthermore, if interconnected, stained objects were considered a single vessel. Ten regions of interest were sufficient for accurate microvessel density measurements. Intra-observer and inter-observer variability were low (intraclass correlation coefficient > 0.7) if the observers were adequately trained.

Clinicopathological correlation of endocan expression and survival in epithelial ovarian cancer

INTRODUCTION

Endothelial-cell-specific molecule-1 or endocan is a proteoglycan with tumorigenic activity through both its glycan and protein cores. Endocan mRNA is identified as one of the most significant molecular signatures defining a poor prognosis in lung, breast, kidney, and hepatocellular cancer.

OBJECTIVE

To assess the clinical value of endocan expression in ovarian cancer tissues in association with other prognostic factors and its impact on overall survival.

SETTING

Oncology unit of Zagazig University Hospitals, Egypt.

STUDY DESIGN

Prospective observational cohort.

PATIENTS AND METHODS

One hundred primary ovarian cancer patients were recruited as study group, another 100 patients undergoing hysterectomy and oophorectomy due to uterine fibroid were the control group. Angiogenesis was determined by immunohistochemical staining, using anti-endocan, and anti vascular endothelial growth factor (VEGF) monoclonal antibodies.

RESULTS

Endocan was expressed in endothelium of ovarian cancer tissue specimens in all patients with no expression in endothelium of normal ovarian tissue in the control group. VEGF was also expressed in endothelium of all specimens of ovarian cancer tissue, compared with 70% expression in normal ovarian tissue specimens in the control group. A significant association was found between endocan-microvessel density (MVD) and tumor histology, tumor size, staging, and grading. No significant association was found between VEGF expression and any of the clinicopathological variables. Overall survival of patients was inversely associated with endocan-MVD (P < 0.01). Multivariate analysis showed that endocan-MVD was an independent prognostic marker for overall survival of epithelial ovarian cancer (P < 0.01).

CONCLUSION

Endocan could be a reliable marker to predict the survival in epithelial ovarian cancer patients.