Selective estrogen receptor modulator with estrogen does not affect the proliferation and apoptosis of uterine leiomyoma cells

Background: The administration of menopausal hormone therapy (MHT) in women with uterine leiomyomas is still debated. The purpose of this article is to study the proliferation and apoptosis of uterine leiomyoma cells under the impact of selective estrogen receptor modulator (SERM) combined with estrogen. Methods: Primary cultured uterine leiomyoma cells in the perimenopausal period were treated with estrogen (17- beta estradiol) + SERM (raloxifene) as the tissue selective estrogen complex (TSEC) group, while both estrogen + medroxyprogesterone acetate (E+P) and estrogen (E) alone as were used as control groups. The expression of proliferating cell nuclear antigen (PCNA) and B-cell lymphoma-2 (Bcl-2) proteins was assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay and western-blot analysis, respectively. Results: The proliferation in the TSEC group was weaker than the control groups (P<0.001). There was no statistical difference between the TSEC and blank control group on cell proliferation at 72 h (P=0.13). However, there was a significant difference between the other groups (P<0.001). PCNA expression of TSEC was lower than that of the E + P and E groups (P<0.05). There was no statistical difference in the expression of PCNA between the TSEC and blank control groups (P=0.63). Bcl-2 expression of TSEC was lower than that of the E + P and E groups (P<0.05). There was no statistical difference in the expression of Bcl-2 between the TSEC group and the blank control group (P=0.60). Conclusions: SERM combined with estrogen may have a better safety for perimenopausal women with uterine leiomyoma in MHT.