Objective: To investigate the expression of vascular endothelial growth factor (VEGF) mRNA and thrombospondin-1 (TSP-1) mRNA in endometriosis.
Design: Molecular studies in human tissue.
Setting: Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, P. R. China.
Patient(s): Patients undergoing laparoscopy for infertility or other benign gynecologic conditions.
Intervention(s): Biopsies were taken from endometriotic lesions (red peritoneal lesion, ovarian endometrioma, and unterosacral ligament nudule) and eutopic endometrium during laparoscopy.
Main outcome measure(s): mRNA expression from endometriotic lesion and eutopic endometrium was analyzed by reverse transcriptase polymerase chain reaction (PCR) and Northern blotting.
Result(s): Among the endometriotic lesions, red peritoneal lesions expressed higher levels of VEGF mRNA and lower levels of TSP-1 mRNA, whereas ovarian endometrioma expressed lower levels of VEGF mRNA and higher levels of TSP-1 mRNA. Eutopic endometrium of women with endometriosis had higher expression levels of VEGF mRNA and lower expression levels of TSP-1 mRNA than that of women without endometriosis.
Conclusion(s): The expression of VEGF and TSP-1 in endometriotic lesions appears to be associated with the extent of their neovascularization. The imbalance in expression of VEGF and TSP-1 in the endometrium may play a role in the development of endometriosis.