Changes in β-Catenin Expression in the Anterior Vaginal Wall Tissues of Women With Pelvic Organ Prolapse: A Potential Pathophysiological Mechanism.

OBJECTIVES

The purpose of this study was to investigate the expression of β-catenin in the lamina propria of the anterior vaginal wall of women with pelvic organ prolapse (POP) compared with the expression in the controls.

METHODS

Anterior vaginal wall tissues were obtained from women undergoing POP surgery for stage 3 or greater POP (POP group, n = 30; age, 58 ± 7.839 years), with a menopause rate of 70%, and from women without POP undergoing hysterectomy for benign indications (control group, n = 30; age, 54.7 ± 7.173 years), with a menopause rate of 50%. Hematoxylin and eosin staining and Masson trichrome staining were performed on anterior vaginal wall sections. β-Catenin, p-β-catenin, glycogen synthase kinase 3β (GSK3β), p-GSK3β, collagen I, collagen III, MMP2, MMP9, TIMP2, caspase 3, proliferating cell nuclear antigen, and cyclin D1 were evaluated using immunohistochemical analysis. Lamina propria tissues were obtained for Western blot analyses.

RESULTS

Hematoxylin and eosin staining and Masson trichrome staining showed that the collagen fibers were more disorganized and fragmented in the POP group than in the control group. In the POP samples, β-catenin (mean density, POP vs control, 0.43 ± 0.13 vs 0.58 ± 0.16), p-GSK3β, collagen I, collagen III, proliferating cell nuclear antigen, and cyclin D1 were downregulated in the lamina propria, whereas in the control group, p-β-catenin, TIMP2, and caspase 3 were downregulated (P < 0.05 for all). GSK3β was not different between the 2 groups (P > 0.05).

CONCLUSION

We demonstrated that decreased β-catenin may play an important role in the onset of POP by affecting collagen anabolism.