Indeed, HCC-M and HCC-T show high levels of linker phosphorylation of Smad3 and nuclear staining, making the relevance of such mechanism probable in these HCC cell lines and as well in human disease, since preliminary data with HCC patient samples suggest the occurrence of Smad3L-phosphorylation in late stage disease (data not shown), which now will be systematically investigated. Here, SMAD3 is linked to hepatocellular carcinoma.