Hormone-replacement therapy influences gene expression profiles and is associated with breast-cancer prognosis: a cohort study.

ABSTRACT:

Background

Postmenopausal hormone-replacement therapy (HRT) increases breast-cancer risk. The influence of HRT on the biology of the primary tumor, however, is not well understood.

Methods

We obtained breast-cancer gene expression profiles using Affymetrix human genome U133A arrays. We examined the relationship between HRT-regulated gene profiles, tumor characteristics, and recurrence-free survival in 72 postmenopausal women.

Results

HRT use in patients with estrogen receptor (ER) protein positive tumors (n = 72) was associated with an altered regulation of 276 genes. Expression profiles based on these genes clustered ER-positive tumors into two molecular subclasses, one of which was associated with HRT use and had significantly better recurrence free survival despite

SUBMITTER: Hall P 

PROVIDER: S-EPMC1555602 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature