Expression and Significance of Transforming Growth Factor-β1 and Connective Tissue Growth Factor in Pubocervical Fascia of Women With Pelvic Organ Prolapse

Abstract

Objective To investigate the role of transforming growth factor (TGF)-β1 and connective tissue growth factor (CTGF) in the development of pelvic organ prolapse (POP). Methods From May 2009 to December 2009, 30 patients with POP underwent vaginal hysterectomy in Renmin Hospital of Wuhan University were enrolled in POP group, among whom according to pelvic organ prolapse quantitation (POP-Q) were divided into POP-Q Ⅱ° group (n=10), POP-Q Ⅲ° group (n=10) and POP-Q Ⅳ° group (n=10). Meanwhile, pubocervical fascia samples of 20 patients were selected as controls treated by vaginal hysterectomy (control group, n=20). Immunohistochemical staining and Western blot were performed to detect the expression of TGF-β1 and CTGF. The study protocol was approved by the Ethical Review Board of Investigation in Human Being of Renmin Hospital of Wuhan University. Informed consent was obtained from all participants. Results ① By Immunohistochemical staining, TGF-β1 and CTGF were mainly expressed in the cytoplasm. The positive rate of TGF-β1 and CTGF expression in pubocervical fascia in POP group were 46.7%(14/30) and 50.0%(15/30), with 70.0% (7/10) and 80.0%(8/10) in POP-Q Ⅱ° group, 50.0% (5/10) and 60.0%(6/10) in POP-Q Ⅲ° group, and 20.0%(2/10) and 10.0%(1/10) in POP-QⅥ° group, respectively, which was significantly lower than those of control group [(90.0%, 18/20) and 85.0% (17/20)] (χ2=27.242,χ2= 23.958; P<0.05). The expression of TGF-β1 and CTGF were significantly negatively correlated with POP-Q grade (r=-0.409, -0.572 ; P <0.05). There were significantly positive correlation between the expression of TGF-β1 and CTGF (r=0.401, P<0.05).② The expression of TGF-β1 and CTGF in POP-Q Ⅱ°, POP-Q Ⅲ° and POP-Q Ⅳ° groups were 0.4344±0.097, 0.2441± 0.060, 0.1844±0.041, 0.1345±0.033 and 1.2732±0.180,0.2132±0.028, 0.1045±0.023, 0.0034± 0.001, respectively, through Western blot. The expression of TGF-β1 in POP-Q Ⅱ°, POP-QⅢ° and POP-Q Ⅳ° groups were all significantly lower than those of control group (P= 0.000). There were no significant differences in the expression of TGF-β1 for each other among POP groups (P= 0.068, 0.126) excluding the comparison between POP-QⅡ°, POP-Q Ⅲ° and POP-Q Ⅳ° groups (P= 0.000). The expression of connective tissue growth factor in POP-Q Ⅱ°, POP-Q Ⅲ° and POP-QⅣ° groups were all significantly lower than those of control group (P= 0.000) and significant differences were also detected among POP-Q Ⅱ°, POP-QⅢ° and POP-QⅣ° groups (P=0.000). Conclusion TGF-β1 and CTGF expression is associated with POP, especially POP-Q grade. Key words: pelvic organ prolapse; transforming growth factor-β1; connective tissue growth factor