Down-regulation of proliferation and up-regulation of apoptosis by gonadotropin-releasing hormone agonist in cultured uterine leiomyoma cells

Abstract

Objective: To elucidate the direct effects of gonadotropin-releasing hormone agonist (GnRHa) on the growth of human uterine leiomyoma cells, cell proliferation and apoptosis in cultured leiomyoma cells treated with GnRHa were investigated. Methods: Isolated leiomyoma cells were subcultured in DMEM supplemented with 10% FBS for 5 days and stepped down to serum-free conditions for an additional 6 days in the presence or absence of graded concentrations of GnRHa (10 29 mol/l to 10 212 mol/l). The effects of GnRHa on the number of viable cells, expression of proliferating cell nuclear antigen (PCNA), Fas and Fas ligand, and apoptosis in cultured leiomyoma cells were examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide) assay, immunocytochemical analysis, Western blot analysis and TUNEL assay respectively. RT-PCR was performed to detect the expression of GnRH receptor mRNA in cultured leiomyoma cells. Results: Treatment with GnRHa resulted in a decrease in the number of cultured viable leiomyoma cells assessed by MTT assay in a dose-dependent manner compared with that in control cultures ðP , 0:01Þ: The growth inhibition of cultured leiomyoma cells treated with GnRHa in concentrations higher than 10 210 mol/l was associated with the suppression of the proliferative potential characterized by a decrease in PCNA-positive rate of the cultured cells ðP , 0:01Þ and an increase in the apoptosis-positive rate assessed by TUNEL assay ðP , 0:05 and P , 0:01Þ: GnRHa markedly increased the expression of Fas and induced the expression of Fas ligand in the cultured leiomyoma cells on the basis of Western blot analysis. These direct effects of GnRHa on the number of viable cultured leiomyoma cells, PCNA-positive rate, apoptosis-positive rate and Fas/Fas ligand expression in the cultured leiomyoma cells were only attained after the 4-day treatment. RT-PCR analysis revealed that GnRH receptor mRNA was expressed in cultured leiomyoma cells. Conclusions:The present results demonstrate that GnRHa directly inhibits the growth of human uterine leiomyoma cells by suppressing cell proliferation and inducing apoptosis, which might be associated with the increase in Fas expression and the induction of Fas ligand expression in the cells.

Ethnic distribution of estrogen receptor-α polymorphism is associated with a higher prevalence of uterine leiomyomas in black Americans

“…Receptor function could also be affected through differential splicing of mRNA (46,47) or alternation of other transcriptional elements within the introns (48). Further, it is possible that some of these polymorphisms serve as markers by being in linkage disequilibrium with other as yet undetected sequence alterations of functional significance for the ER␣ gene (49).…”

The −2549 insertion/deletion polymorphism of VEGF gene associated with uterine leiomyoma susceptibility in women from Southeastern Iran

“…They www. journals.viamedica.pl/ginekologia_polska include not only ovarian steroids, angiogenesis, and growth factors, but also the apoptosis related factors [6]. It is well known that ULs respond to the ovarian hormones such as estrogen and progesterone, and their epidemiology parallels the ontogeny and life-cycle changes in genital hormones [7].…”

Antioxidant status in women with uterine leiomyoma: relation with sex hormones

“…Through this mechanism, GnRH can reduce fibroid volume by 50% within 3-6 months (Wang et al 2002, Maruo et al 2004. Clinical evidence of sex steroids involvement in leiomyoma growth can be seen with the shrinkage of leiomyoma during menopause and after GnRH administration in hypoestrogenic and hypoprogesterone states (Neuwirth and Moritz 2008).…”