Transforming Growth Factor Beta 1 and p44/42 Expression in Cardinal Ligament Tissues of Patients with Pelvic Organ Prolapse

BACKGROUND: Pelvic organ prolapse (POP) is a disease associated with collagen loss and decreased fibroblast proliferation. Transforming growth factor beta 1 (TGF-β1) controls collagen synthesis and degradation in pelvic connective tissue. Although the p44/42 MAPK pathway has been implicated in collagen production and extracellular matrix disorders, its expression in POP remains unknown. This study aimed to investigate TGF-β1 and p44/42 expression in cardinal ligament tissues in patients with POP. MATERIAL/METHODS: Cardinal ligament tissues were obtained from 30 patients with POP (POP group) and 30 patients with benign gynecological disorders who had undergone total hysterectomy (control group). The clinical characteristics of the 2 groups were summarized. Immunohistochemical staining and western blotting analysis were performed to measure the expression of TGF-β1, p44/42, phospho-p44/42, MMP9, TIMP1, caspase 3, collagen I, and collagen III in the cardinal ligament tissues. RESULTS: Patients with POP had significantly lower TGF-β1 and phospho-p44/42 levels than did control patients (P<0.05). The expression of TIMP1, collagen I, and collagen III was significantly lower, and the expression of MMP9 and caspase 3 was significantly higher in the POP group than in the control group (P<0.05). Moreover, the expression of phospho-p44/42 was positively correlated with the expression of TGF-β1, collagen I, and collagen III. CONCLUSIONS: The expression levels of phospho-p44/42 and TGF-β1 were decreased in patients with POP and were positively correlated with collagen expression. Low levels of TGF-β1 and phospho-p44/42 expression in patients with POP may be associated with the occurrence of POP.