Gene Expression Profiles of Estrogen Receptor–Positive and Estrogen Receptor–Negative Breast Cancers Are Detectable in Histologically Normal Breast Epithelium

Abstract

Gene expression differs in NlEpi of breasts containing ER+ compared with ER- breast cancers. These differences echo differences in ER+ and ER- invasive cancers. NlEpi gene expression may help elucidate subtype-specific risk signatures, identify early genomic events in cancer development, and locate targets for prevention and therapy.