LX2 (a human immortalized hepatic stellate cell line), HSC-T6 (a rat immortalized hepatic stellate cell line), and HeLa (a human cervical carcinoma cell line) cells were cultured at 37°C in an atmosphere of 5% CO2 in Dulbecco's Modified Eagle Medium (Euroclone - Milan, Italy) supplemented with 10% Fetal Bovine Serum (Euroclone), 2 mM L-Glutamine and antibiotics. HepG2 cells (a human hepatocarcinoma cell line) were cultured at 37°C in an atmosphere of 5% CO2 in Eagle's Minimum Essential Medium (Euroclone) containing 10% Fetal Bovine Serum, 2 mM L-Glutamine and antibiotics.