Luminal a

T47D and MCF-7 breast cancer cell lines of the Luminal A subtype (American Type Culture Collection (ATCC), Manassas, Virginia) were used. The MCF-7 cell line was cultured in DMEM (Biowest, France) supplemented with 10% FBS, 1% P/S, and 0,01 mg/mL insulin. The T47D line was cultured in RPMI-1640 (Thermo Fisher Scientific, France) with 10% FBS and 1% P/S. Cells were passaged with 0.25% trypsin-EDTA (Merck Millipore Corporation, Germany) when they reached 80–90% confluency.

The human breast cancer cell lines: MCF-7 (Invasive breast ductal carcinoma, Luminal A, was obtained from American Type Culture Collection, Manassas, VA, USA), MDA-MB-468 (Metastatic breast adenocarcinoma, Triple negative) and BT-549 (Invasive breast ductal carcinoma, Triple negative) were cultured as previously reported^{23 (link)}, and were provided by Dr. Pedro Romero (Ludwig Center for Cancer Research, Department of Oncology, Faculty of Biology and Medicine University of Lausanne, Switzerland). Tumor cells were proven Mycoplasma free using a MycoProbe Mycoplasma Detection Kit (R&D Systems) and maintained with ciprofloxacin (0.5 μg/mL).