Editorial

Roles for estrogen and progesterone in breast cancer prevention

D Joseph Jerry^1,2

¹  Department of Veterinary & Animal Sciences, University of Massachusetts-Amherst, 161 Holdsworth Way, Amherst, Massachusetts 01003, USA

²  Pioneer Valley Life Sciences Institute, 3601 Main Street, Springfield, Massachusetts 01199, USA

author email corresponding author email

Breast Cancer Research 2007, 9:102doi:10.1186/bcr1659

Published:	21 March 2007

See related research article by Rajkumar et al,. http://breast-cancer-research.com/content/9/1/R12 and related letter by Ferretti et al., http://breast-cancer-research.com/content/9/6/402

Abstract

Prevention has long been the holy grail of breast cancer research. The significant reduction in breast cancer risk afforded by a full-term pregnancy early in life suggests the great potential of preventive strategies. In contrast to the risks associated with prolonged exposures, exogenous estrogen and progesterone for short durations can mimic the protective effects of pregnancy in carcinogen-induced mammary tumor models. Rajkumar and coworkers have now demonstrated that these hormones protect mice from mammary tumors initiated by a spectrum of oncogenic alterations that are common in breast cancers. Although differences between rodent models and humans remain, the results reveal that exogenous estrogen and progesterone potently inhibit tumorigenesis through multiple pathways and establish a foundation for strategies to prevent breast cancer.