Objective: To investigate the expressions of vascular endothelial growth factor (VEGF), VEGFRs and activation of signal transducers and activators of transcription (STATs) in ovarian epithelial carcinoma and the relationships among them.
Methods: The tissue samples of 42 primary ovarian epithelial carcinoma, 29 benign ovarian tumor and 11 normal ovarian tissue were used to determine the expression of VEGF, VEGFR1, VEGFR2, P-STAT1, P-STAT3, P-STAT5 and P-STAT6 proteins by immunohistochemical staining.
Results: VEGF in ovarian carcinomas was significantly higher than that in benign and normal ovarian tissues. VEGFRs expression was in agreement with VEGF expression. In tumor cells and endothelial cells of ovarian carcinomas, expressions of P-STAT3 and P-STAT5 were significantly higher than those in benign and normal ovarian tissues. In endothelial cells, the expression of VEGFR1 and P-STAT5 closely correlated with each other, as well as VEGFR2 and P-STAT3. However, in ovarian carcinoma cells, expressions of VEGF, VEGFR1 and VEGFR2 were significantly correlated with P-STAT3 and P-STAT5, but not with P-STAT1 and P-STAT6.
Conclusions: There exist overexpressions of VEGF, VEGFRs, and STAT3, STAT5 activation. Furthermore, these results indicate that VEGF secreted by ovarian carcinoma cells may activate STAT pathway via VEGFRs in ovarian carcinoma themselves.