Culturing Human Breast Cancer and Non-Malignant Cells

Human breast cancer and non-malignant epithelial cells were obtained from the American Type Culture Collection (Rockville, MD, USA). MDA-MB-231 cells stably expressing luciferase (MDA-MB-231-Luc) were obtained from Caliper Lifesciences (Hopkinton, MA, USA). All cell culture media contained 10% FBS and 1% penicillin–streptomycin unless otherwise specified. Human MCF-7, MDA-MB-231 and MDA-MB-435 cells were grown in DMEM media. The MCF-7 p53 KD and MCF-7 MDM2 KD inducible cells were generated using the previously described method^{53 (link),54 (link)} and were grown in the same media as MCF-7 cells, but supplemented with 0.5 μg ml ⁻¹ puromycin or 10 μg ml ⁻¹ blasticidin and 0.5 μg ml ⁻¹ puromycin (Sigma-Aldrich Co.), respectively. MDAMB-468 cells were grown in DMEM/F-12 Ham’s media (DMEM/F-12 1:1 mixture). The MCF-10A growth medium was composed of DMEM/F-12, supplemented with 5% donor horse serum, 20 ng ml ⁻¹ epidermal growth factor, 10 μg ml ⁻¹ insulin, 0.5 μg ml ⁻¹ hydrocortisone (Sigma-Aldrich Co.) and 100 μg ml ⁻¹ cholera toxin (Cambrex, Westborough, MA, USA). Human MDAMB-231-Luc cells were grown in DMEM media containing 0.1 mM MEM non-essential amino acids and 2 mM L-glutamine.