2.1 Cell culture
HCT-116 cells (human colon cancer cell line) were initially obtained from the American Type Culture Collection (USA). Cells were cultured in Dulbecco’s modified eagle medium (Gibco, Invitrogen) supplemented with 10% fetal bovine serum (FBS) and 1% penicillin and streptomycin (pen/strep) solution under standard conditions (37°C, 5% CO2). HCoMECs (Innoprot, Spain) were cultured in an endothelial cell medium with 5% FBS, 1% of endothelial cell growth supplement, and 1% of pen/strep solution. The medium was replaced every 3 days. Subculture of cells was performed before 90% confluence using 0.25% trypsin/EDTA (Gibco) for 5 min at 37°C.