Semin Reprod Med 2004; 22(1): 45-50
DOI: 10.1055/s-2004-823026
Copyright © 2004 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Aromatase and Endometriosis

Serdar E. Bulun1 , Zongjuan Fang1 , Gonca Imir1 , Bilgin Gurates1 , Mitsutoshi Tamura2 , Bertan Yilmaz1 , David Langoi2 , Sanober Amin1 , Sijun Yang2 , Santanu Deb1
  • 1Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Northwestern University, Chicago, Illinois
  • 2Department of Obstetrics and Gynecology, University of Illinois at Chicago, Illinois
Further Information

Publication History

Publication Date:
13 April 2004 (online)

Aromatase P450 (P450arom) is the key enzyme for biosynthesis of estrogen, which is an essential hormone for the establishment and growth of endometriosis. There is no detectable aromatase enzyme activity in normal endometrium; therefore, estrogen is not locally produced in endometrium. Endometriosis tissue, however, contains very high levels of aromatase enzyme, which leads to production of significant quantities of estrogen. Moreover, one of the best-known mediators of inflammation and pain, prostaglandin E2, strikingly induces aromatase enzyme activity and formation of local estrogen in this tissue. Additionally, estrogen itself stimulates cyclo-oxygenase-2 and therefore increases the formation of prostaglandin E2 in endometriosis. We were able to target this positive feedback cycle in endometriosis using aromatase inhibitors. In fact, pilot trials showed that aromatase inhibitors could decrease pelvic pain associated with endometriosis.


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Serdar E BulunM.D. 

Department of Obstetrics and Gynecology, Northwestern University

333 E. Superior Street, Suite 484, Chicago, IL 60611