Apparently, the transforming growth factor-β (TGF-β) is another important extracellular factor involved in the progressive features of CK19-positive HCC cells as the inhibition of transforming growth factor-β receptor 1 (TGFβR1) could significantly attenuate the proliferation capability of CK19-positive HCC 30. The gene discussed is TGFBR1; the disease is hepatocellular carcinoma.