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

Abstract

Cyclo-oxygenase-2 seems to be involved at various steps in the processes of tumor progression. The objective of this study was to examine the relationship between cyclo-oxygenase-2 expression and tumor proliferation, apoptosis and angiogenesis in patients with advanced stage high-grade ovarian carcinoma. Specimens from 118 patients with high-grade and advanced stage (III, IV) serous ovarian carcinoma were evaluated by immunohistochemistry for cyclo-oxygenase-2, Ki-67, vascular endothelial growth factor, and bcl-2 expression. Tumor microvessel density was assessed with CD34 immunostaining. We investigated the relationships between cyclo-oxygenase-2 expression and clinicopathologic characteristics, tumor angiogenesis (tumor microvessel density and vascular endothelial growth factor expression), and tumor proliferation and apoptosis. The effect of cyclooxygenase-2 expression on patient survival was determined. There was a significant positive correlation between cyclo-oxygenase-2 expression in tumor cells and markers of tumor proliferation and angiogenesis. In univariate survival analysis, high cyclo-oxygenase-2 and high Ki-67 expression showed a significant impact of on patient survival (P < .001). In multivariate regression analysis, only Ki-67 expression retained its significance as an independent poor prognostic factor (death hazard ratio, 2.0; 95% CI, 1.2-3.3; P < .001). Expression of cyclo-oxygenase-2 correlates with tumor proliferation and tumor angiogenesis but not with apoptotic markers (bcl-2 expression) in high-grade, advanced-stage serous ovarian carcinoma.