Synergistic control of sex hormones by 17b-HSD type 7 : a novel target for estrogen-dependent breast cancer

Authors: Wang, Xiao QiangGérard, CatherineThériault, Jean-FrançoisPoirier, DonaldDoillon, CharlesLin, Sheng-Xiang
Abstract: 17b-hydroxysteroid dehydrogenase (17b-HSD) type 1 is known as a critical target to block the final step of estrogen production in estrogen-dependent breast cancer. Recent confirmation of the role of dyhydroxytestosterone (DHT) in counteracting estrogeninduced cell growth prompted us to study the reductive 17b-HSD type 7 (17b-HSD7), which activates estrone while markedly inactivating DHT. The role of DHTin breast cancer cell proliferationis demonstrated byitsindependent suppression of cell growthin the presence of a physiological concentration of estradiol (E2). Moreover, an integral analysis of a large number of clinical samples in Oncomine datasets demonstrated the overexpression of 17b-HSD7 in breast carcinoma. Inhibition of 17b-HSD7 in breast cancer cells resulted in a lower level of E2 and a higher level of DHT, successively induced regulation of cyclinD1, p21, Bcl-2, and Bik, consequently arrested cell cycle in the G0/G1 phase, and triggered apoptosis and auto-downregulation feedback of the enzyme. Such inhibition led to signifi- cant shrinkage of xenograft tumors with decreased cancer cell density and reduced 17b-HSD7 expression. Decreased plasma E2 and elevated plasma DHT levels were also found. Thus, the dual functional 17b-HSD7 is proposed as a novel target for estrogen-dependent breast cancer by regulating the balance of E2 and DHT. This demonstrates a conceptual advance on the general belief that the major role of this enzyme is in cholesterol metabolism.
Document Type: Article de recherche
Issue Date: 12 May 2015
Open Access Date: Restricted access
Document version: VoR
This document was published in: Journal of molecular cell biology, Vol. 7 (6), 568 (2015)
Oxford University Press
Alternative version: 10.1093/jmcb/mjv028
Collection:Articles publiés dans des revues avec comité de lecture

Files in this item:
Description SizeFormat 
J Mol Cell Biol-2015-Wang-568-79.pdf
1.26 MBAdobe PDF    Request a copy
All documents in CorpusUL are protected by Copyright Act of Canada.