As the representative HCC cell lines we investigated were established from samples obtained from different patients, it is possible that the difference in chemosensitivity of the EpCAM+ and CD90+ HCC cells to sorafenib treatment may be related to the different genetic/epigenetic/genomic changes that these cell lines have acquired independently (intertumor heterogeneity). This evidence concerns the gene EPCAM and hepatocellular carcinoma.