Cultured Human TNBC Cell Lines

Human TNBC cell lines were cultured in 5% carbon dioxide (CO₂). Luminal AR MDA-MB-453 cells were purchased from the American Type Culture Collection (ATCC, Rockville, MD) and maintained in DMEM with 10% FBS. SUM159PT cells, expressing moderate levels of AR [35 (link)], were obtained in 2013 from the University of Colorado Cancer Center (UCCC) Tissue Culture Core (Aurora, CO) and maintained in Ham’s/F-12 with 5% FBS, 1% HEPES, 1 μg/mL hydrocortisone and 5 μg/mL insulin. Only cells of under ten passages were used in this study. All cell lines were routinely tested for mycoplasma contamination, and human cell lines were authenticated in 2017 by short tandem repeat analysis in the UCCC Tissue Culture Core. The androgen dihydrotestosterone (DHT; Sigma-Aldrich Corporation, St. Louis, MO) used for in vitro experiments was diluted in ethanol (EtOH). The AR and CYP17 lyase inhibitor seviteronel (Sevi) was provided by Innocrin Pharmaceuticals, Inc. (Durham, NC). The CDK4/6 inhibitor Abemaciclib (Abem) was purchased from Selleck Chemical LLC. (Houston, TX). All drugs were diluted in dimethyl sulfoxide (DMSO).