IL6 and liver cancer: To examine whether IL-6 participates in the immunoregulatory capacity of MDSCs mediated by HSCs, liver cancer cells (HCCs, Hepa 1-6 cell line, 1 × 106 cells per mouse) were implanted into the left liver with or without HSCs (3.3 × 105 cells per mouse) harvested from wild-type or IL-6 knockout mice by using the orthotopic liver tumor inoculation model.