Expression of angiogenic factors in endometriosis: relationship to fibrinolytic and metalloproteinase systems.

BACKGROUND Endometriosis is a highly prevalent, benign disease in which the angiogenic, fibrinolytic and metalloproteinase (MMP) systems may be implicated. The objective of this study is to analyse mRNA expression and protein levels of several angiogenic factors and to correlate them with several components of the fibrinolytic and MMP systems in samples from 71 women with endometriosis and 50 controls. METHODS AND RESULTS Eutopic endometrium showed higher mRNA expression of vascular endothelial growth factor (VEGF) in patients than in controls. However, ovarian endometrioma had lower VEGF mRNA levels than did the eutopic endometrium of patients. Similar results were obtained for VEGF protein levels. On the other hand, a significant increase in thrombospondin-1 (TSP-1) levels was observed in ovarian endometrioma than in eutopic endometrium. The peritoneal fluid from women with endometriosis showed a significant increase in VEGF, urokinase-type plasminogen activator (uPA) and MMP-3 levels than that of controls. A significant correlation was observed between the levels of VEGF and uPA in endometrium and in peritoneal fluid. CONCLUSIONS Endometrium and peritoneal fluid from women with endometriosis have increased levels of VEGF, uPA and MMP-3 levels. Therefore, the development of endometriotic implants at ectopic sites may be facilitated, promoting the progress of the endometriosis.