Expression of vascular endothelial cell growth factor and its receptor flk-1 in endometriosis

Objective To study the expressions of vascular endothelial cell growth factor (VEGF) and its receptor flk-1 in ectopic and eutopic endometrium of endometriosis and their correlation with microvessel density (MVD).Methods Endometrium specimens were collected from 26 health women and 31 patients with endometriosis. Expression of VEGF and flk-1 were examined by immunohistochemical staining and Western blot.Results ① The VEGF expression in ectopic endometrium was significantly higher than that in eutopic endometrium of endometriosis. VEGF expression in the secretory phase of eutopic endometrium of endometriosis was stronger than that in control group. ② A significant cyclic changes were observed both in eutopic and ectopic endometrium of endometriosis. VEGF expression in secretory phase was significantly higher than that in poliferative phase. ③ The receptor flk-1 was mainly expressed in the vascular endothelial cells. VEGF expression was positively related to microvessel density (MVD) in endometrial gland of endometriosis. Conclusion VEGF is an important factor that may contribute to the pathegenesis of endometriosis by promoting neovascularization.