Bt474

Breast cancer cell lines MCF-7 (TCHu74), MDA-MB-231 (TCHu104) were purchased from the Shanghai Cell Bank, Chinese Academy of Sciences. BT474 (HTB-20™), and T-47D (HTB-133) and normal mammary epithelial cell line MCF 10A (CRL-10317) were obtained from the American Type Culture Collection (Manassas, VA, USA). The cell identity was confirmed by STR analysis. The MCF-7, BT474, MDA-MB-231 and T-47D cells were cultured in Dulbecco's modified Eagle's medium (DMEM; HyClone; GE Healthcare Life Sciences, Logan, UT, USA) supplemented with 10% fetal bovine serum (FBS) (HyClone; GE Healthcare Life Sciences). The MCF-10A cells were cultured in DMEM/F12 medium (HyClone; GE Healthcare Life Sciences) containing 5% horse serum (Gibco; Thermo Fisher Scientific, Inc., Waltham, MA, USA), 1% penicillin/streptomycin (HyClone; GE Healthcare Life Sciences), 20 ng/ml of EGF (Gibco; Thermo Fisher Scientific, Inc.), 0.5 µg/ml of hydrocortisone (Sigma, St. Louis, MO, USA). All cells were incubated in a humidified atmosphere with 5% CO₂ and humidified sphere of 95% at 37°C.

The human breast cancer cell lines T-47D, MCF-7, MDA-MB-231 and BT-474, as well as 293T cells were purchased from the Type Culture Collection of the Chinese Academy of Sciences; all cell lines were authenticated by American Type Culture Collection. The T-47D, MDA-MB-231 and 293T cells were routinely cultured in DMEM (HyClone; GE Healthcare Life Sciences) supplemented with 10% fetal bovine serum (FBS; Lonsera Science); the BT-474 cells were cultured in RPMI-1640 medium (HyClone; GE Healthcare Life Sciences) supplemented with 10% FBS; and the MCF-7 cells were cultured in DMEM supplemented with 10% FBS, 1% sodium glutamate and 0.01 mg/ml bovine insulin. All the cells were incubated at 37°C in a humidified atmosphere with 5% CO₂.