HGF and neoplasm: HSC, as the central modulators of the tumor microenvironment, have long been considered as a tumor promoter during hepatocarcinogenesis by the secretion of growth factors such as hepatocyte growth factor (HGF), platelet-derived growth factor (PDGF) and connective tissue growth factor (CTGF), altering components of the ECM, regulating angiogenesis and immune surveillance [17–21].