Expression and regulation of estrogen-converting enzymes in ectopic human endometrial tissue.

OBJECTIVE

To investigate the regulation of estrogen-converting enzymes in human ectopic endometrial tissue.

DESIGN

Animal study.

SETTING

Academic medical center.

ANIMAL(S): Sixty female nude mice with implanted human endometrial tissue.

PATIENT(S): Twenty-two premenopausal women undergoing endometrial biopsy or hysterectomy.

INTERVENTION(S): Human endometrial tissue was implanted into the peritoneal cavity of nude mice, and the effect of therapeutic drugs on transcription of steroid receptors and estrogen-converting enzymes was analyzed.

MAIN OUTCOME MEASURE(S): Transcript levels of steroid hormone receptors, 17beta-hydroxysteroid dehydrogenase type 1 and 2, aromatase, and steroid sulfatase as well as proliferation rate were analyzed in the human ectopic endometrial tissue.

RESULT(S): Steroid receptors and estrogen-converting enzymes were expressed in the ectopic human endometrial fragments. Application of medroxyprogesterone acetate, dydrogesterone, danazol, and the aromatase inhibitor finrozole significantly inhibited aromatase transcription. In addition, danazol caused a significant decrease in transcription of steroid sulfatase, and finrozole, of 17beta-hydroxysteroid dehydrogenase type 1 in parallel to a decrease in proliferation rate in the ectopic human endometrial tissue.

CONCLUSION(S): Pharmacological regulation of transcription of estrogen-converting enzymes in human endometrium cultured in nude mice may help to develop new therapeutic concepts based on local regulation of estrogen metabolism in endometriosis.