Cell culture

The human liver cancer cell lines Huh7 and PLC/PRF/5 were obtained from the Korean Cell Line Bank (Seoul, Korea) and maintained in Roswell Park Memorial Institute medium (RPMI 1640; Welgene, Daegu, Korea) containing 10% fetal bovine serum (FBS; Gibco, Grand Island, NY, USA) and 1% penicillin–streptomycin (P/S; Gibco). The LX2 human HSC line was purchased from Merck Millipore (Darmstadt, Germany) and maintained with Dulbecco’s modified Eagle’s medium (DMEM; Welgene) containing 2% FBS and 1% P/S. Another human HSC line, LI90, was purchased from JCRB Cell Bank (Japan) and cultured in DMEM containing 10% FBS and 1% P/S. An HCC cell line, HepG2, and the WI38 human fibroblast cell line were obtained from ATCC (Manassas, VA, USA). These cell lines were maintained in minimum essential media (Welgene) supplemented with 10% FBS and 1% P/S. Human umbilical vein endothelial cells (HUVECs) were purchased from PromoCells (Heidelberg, Germany) and cultured in endothelial basal medium with supplementary reagents from PromoCells. All cells were maintained at 37 °C in a humidified incubator with 5% CO₂.