Gene expression changes caused by estrogen treatment of breast cancer cells that re-express ERalpha was investigated by infecting ER-negative MDA-MB-231 breast cancer cells for 24 h with recombinant adenovirus encoding full-length human ERalpha (Ad-ERalpha) or control vector (Ad-LacZ), and treating them with 0ยท01% ethanol (vehicle control) or 10-8 M 17beta-estradiol (E2). After 48 h of treatment, total RNA was isolated and used for transcript profiling on Affymetrix GeneChips. Three independent biological replicates of this experiment were carried out.
