Cell lines and cell culture

CT26, HUVECs, SW480, SW620 and HCT116 were obtained from the American Type Culture Collection (ATCC; Manassas, VA, USA). CT26 and SW480 cells were grown in 100-cm² cell culture plates and maintained in RPMI-1640 medium (Gibco; Thermo Fisher Scientific, Inc., Waltham, MA, USA) supplemented with 10% heat-inactivated fetal bovine serum (Gibco; Thermo Fisher Scientific, Inc.), 100 U/ml penicillin and 100 µg/ml streptomycin at 37°C in a humidified atmosphere containing 95% air and 5% CO₂. SW620 and HCT116 cells were maintained in Dulbecco's modified Eagle's medium (DMEM; Gibco; Thermo Fisher Scientific, Inc.) and HUVECs were maintained in DMEM-F12 (Gibco; Thermo Fisher Scientific, Inc.). DMEM and DMEM-F12 were also supplemented with 10% heat-inactivated fetal bovine serum (Gibco; Thermo Fisher Scientific, Inc.), 100 U/ml penicillin and 100 µg/ml streptomycin at 37°C in a humidified atmosphere containing 5% CO₂. Cells in the exponential growth phase were used for all experiments.