Expressions and roles of TGFβ/Smad signal pathway in peritoneum of endometriosis

Abstract

To investigate the expression of transforming growth factor (TGF)-β and Smad pathway expressed in adhesion peritoneums in patients with endometriosis (EM). From Dec. 2009 to Mar. 2010, 11 patients with EM [including 3 patients treated by gonadotropin releasing hormone agonist (GnRH-a) treatment] underwent laparoscopy surgery in Peking Union Medical College Hospital. In the mean time, 9 patients with benign ovarian tumor without EM and peritoneum adhesion were chosen as control. Peritoneum from lateral peritoneal cavity, adjacent from lesion and grossly normal was obtained during surgery. Microstructure of peritoneums was observed by HE staining and Masson staining. The expression of TGF-β1, TGF-β3, Smad 3 and Smad 7 in peritoneums were measured by immunohistochemistry staining and real-time PCR. The effect of GnRH-a on expressions of these markers were also analyzed. (1) Microstructures of peritoneum: enlargement of nucleus of peritoneal mesothelial cells, thickening of connective tissue, distributive disorder of fiber, increasing numbers of fibroblast and inflammatory cells in EM were significantly different from those in control group. (2) The expression of TGF-β1 and 3 in peritoneum were 0.170 ± 0.020 and 0.110 ± 0.010 in EM group, which were significantly higher than 0.070 ± 0.010 and 0.050 ± 0.020 in control group. TGF-β1 was downregulated to 0.130 ± 0.030 and TGF-β3 was upregulated to 0.490 ± 0.090 by GnRH-a. (3) The expression of Smad 3 and 7 were 0.140 ± 0.020 and 0.110 ± 0.020 in peritoneum in EM group, which were significantly higher than 0.024 ± 0.004 and 0.014 ± 0.007 in control group. GnRH-a could upregualted the expression of smad 7 (0.040 ± 0.020), however, but no significant effect was observed on regulating Smad3 expression. The changes of microstructure and the alteration of TGF-β/Smad expression in peritoneum of endometriosis were observed. GnRH-a could regulate the expression of TGF-β and Smad.