GONADOTROPIN-RELEASING-HORMONE AGONIST THERAPY INDUCES APOPTOSIS IN UTERINE LEIOMYOMA

Objective: We examined uterine tissue samples obtained from premenopau sal women with uterine leiomyoma treated with gonadotropin-releasing h ormone agonist (GnRHa) to investigate the mechanism of the effects of GnRHa. Study design: Surgically resected myoma tissue obtained from 26 premenopausal patients with uterine leiomyoma treated with GnRHa, 20 premenopausal patients with uterine leiomyoma who did not receive GnRH a treatment, and 15 postmenopausal women with uterine leiomyoma were e xamined histologically. Results: GnRHa treatment reduced the size of u terine leiomyomata and induced significant hyaline degeneration in tum or tissue. Le(Y)-antigen expression was detected in 18 (69.3%) of 26 G nRHa-treated patients (P <0.02) and in 12 (80.0%) of 15 postmenopausal women (P <0.05), but in only eight (40.0%) of the 20 premenopausal pa tients who did not receive GnRHa. Apoptotic cells, detected by the nic k-end labeling method were observed in 14 patients (53.8%) in the GnRH a-treated group, 10 patients (50.0%) in the non-treated group, and 12 postmenopausal women (80.0%). Conclusion: Our findings suggest that in duction of apoptosis may be a mechanism of the effect of GnRHa in leio myoma.