Gene expression analysis of hormone treated MCF7 breast cancer cells in the presence or absence of cycloheximide

Estrogen receptors (ERs), which mediate the proliferative action of estrogens in breast cancer cells, are ligand-dependent transcription factors that regulate expression of their primary target genes through several mechanisms. In addition to direct binding to cognate DNA sequences, ERs can be recruited to DNA through other transcription factors (tethering), or affect gene transcription through modulation of signaling cascades by non-genomic mechanisms of action. To better characterize the mechanisms of gene regulation by estrogens, we have identified more than 700 putative primary and more than 1500 putative secondary target genes of estradiol in MCF7 cells through microarray analysis performed in the presence or absence of the translation inhibitor cycloheximide. Keywords: drug treatment RNA samples were collected 24 h after treatment of MCF7 cells with vehicle or 17{beta}-estradiol (25 nM). Cells were pre-treated 1 h before E2 stimulation with cycloheximide (CHX, 10 microg/ml). Microarray analysis was performed with four replicates for each condition.