Brca2 is coordinately regulated with Brca1 during proliferation and differentiation in mammary epithelial cells

摘要

We have analyzed the expression of the breast cancer susceptibility gene, Brca2, in mammary epith- elial cells as a function of proliferation and differentiation. Our results demonstrate that Brca2 mRNA expression is tightly regulated during mammary epithelial proliferation and dif- ferentiation, and that this regulation occurs coordinately with Brca1. Specifically, Brca2 mRNA expression is up-regulated in rapidly proliferating cells; is down-regulated in response to serum deprivation; is expressed in a cell cycle-dependent manner, peaking at the G_1/S boundary; and is up-regulated in differentiating mammary epithelial cells in response to glu- cocorticoids.