BMB Rep. 2016; 49(9): 488-496  
Extra-gonadal sites of estrogen biosynthesis and function
Radwa Barakat1,2, Oliver Oakley3, Heehyen Kim4, Jooyoung Jin4 & CheMyong Jay Ko1,*
1Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Illinois 61802, Unites States, 2Department of Toxicology, Faculty of Veterinary Medicine, Benha University, Benha 13518, Egypt, 3Department of Biology, College of Arts and Sciences, Eastern Kentucky University, Kentucky 40475, United States, 4Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea
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Received: August 2, 2016; Published online: September 30, 2016.
© Korean Society for Biochemistry and Molecular Biology. All rights reserved.

Estrogens are the key hormones regulating the development and function of reproductive organs in all vertebrates. Recent evidence indicates that estrogens play important roles in the immune system, cancer development, and other critical biological processes related to human well-being. Obviously, the gonads (ovary and testis) are the primary sites of estrogen synthesis, but estrogens synthesized in extra-gonadal sites play an equally important role in controlling biological activities. Understanding non-gonadal sites of estrogen synthesis and function is crucial and will lead to therapeutic interventions targeting estrogen signaling in disease prevention and treatment. Developing a rationale targeting strategy remains challenging because knowledge of extra-gonadal biosynthesis of estrogens, and the mechanism by which estrogen activity is exerted, is very limited. In this review, we will summarize recent discoveries of extra-gonadal sites of estrogen biosynthesis and their local functions and discuss the significance of the most recent novel discovery of intestinal estrogen biosynthesis.
Keywords: Estrogen, Estrogen receptor, Extra-gonadal

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