Expression data for Control and SMRT-Depleted MCF-7 Cells

Estrogens are an important regulator of breast cancer disease progression, and they function by binding the estrogen receptor-α (ERα) to regulate changes in gene expression. ERα is able to both activate and inhibit gene transcription in a gene-specific manner and do so by binding target DNA sequences and recruiting coactivators and corepressors which can modulate the chromatin environment. Silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) is known to act as coactivator and corepressor of ERα in a gene-specific manner. We used a microarray analysis to examine the gene expression changes that occur when the coregulator SMRT is depleted from the ERα positive MCF-7 breast cancer cell line. We sought to determine the genes that are regulated by depletion of the coregulator SMRT using Affymetrix Human Gene 1.0 ST Array. To this end, we transfected MCF-7 cells with control siRNA or SMRT-targeting siRNA for 48 h and treated for an additional 4 or 24 h with vehicle (0.1% EtOH) or 1 nM estradiol (E2). A total of 24 samples were analyzed, separated into eight groups each with three experimental replicates in each group, siControl-Veh 4 h, siControl -E2 4 h, siSMRT-Veh 4 h, siSMRT-E2 4 h, siControl-Veh 24 h, siControl-E2 24 h, siSMRT-Veh 24 h, siSMRT-E2 24 h.