Effect of mifepristone on the expression of PR, PCNA and Bcl-2 in human uterine leiomyoma cells in vitro

Objective To observe mechanism of mifepristone in therapy of uterine leiomyoma and to investigate the role of progesterone in pathogenesis of leiomyoma and its relationship with apoptosis. Methods The primary cultured leiomyoma cells were treated with different concentration of mifepristone. The cell proliferation was observed and the expression of progesterone receptor (PR)?proliferating cell nuclear antigen (PCNA) and Bcl-2 were measured immunocytochemically.Results The cells from ten uterine tissue specimens could be cultured successfully. The treatment of mifepristone (10 -4 mol/L) suppressed the cell proliferation and the expression of PR, PCNA and Bcl-2. Conclusions The mechanism of mifepristone on leiomyoma growth is that it suppresses the cell proliferation directly and via the antagonistic effect of progesterone. Additionally, it induces apoptosis of leiomyoma cell. This study shows that progesterone plays a role in leiomyoma growth and leiomyoma is a related to apoptosis.