A previous comparative genomics study discriminated two subtypes of human HCC cell lines based on TGF-β1 gene signatures24: PLC/PRF/5, Huh7, Huh6, and HepG2 cells were characterized by an early TGF-β1 gene signature associated with TGF-β1-induced cytostasis and apoptosis; and SNU387, SNU449, SNU475, and SK-Hep1 cells were defined by a late TGF-β1 gene signature lacking TGF-β receptors, and exhibited high levels of epithelial-to-mesenchymal transition (EMT)-associated proteins. Here, TGFB1 is linked to hepatocellular carcinoma.