Cell Line Acquisition and Cultivation

MCF7, CN34-LM1, MDA-MB-231 and their metastatic derivatives were kindly provided by Dr Joan Massague (Memorial Sloan Kettering Cancer Center), and Dr Sohail Tavazoie (Rockefeller University)6 (link). Human umbilical vein endothelial cells (HUVEC) were purchased from LONZA (Basel, Switzerland) and cultured in EGM-2 bullet kit media (LONZA)5 (link). 4T1 derivatives and RAW 264.7 cells were provided by Drs Fred Miller (University of Michigan) and Suk-Jo Kang (KAIST), respectively. CN34-LM1 cells were cultured in M199 medium containing 2.5% FBS, 10 μg ml⁻¹ insulin, 0.5 μg ml⁻¹ hydrocortisone, 20 ng ml⁻¹ EGF and 100 ng ml⁻¹ cholera toxin. All the other cells were cultured in in DMEM supplemented with 10% FBS. The cell lines were recently authenticated by DNA fingerprinting analysis and regularly tested for mycoplasma contamination.