We also noted that all the lines with known PTEN mutations fall into either the synergistic or additive category with the exception of the HCC-38 cell line, which upon review of the Sanger database contains an interchromosomal breakpoint within PTEN (Table 1), and confirmed that all the PTEN mutant lines lack PTEN expression (Fig. 1B). This evidence concerns the gene PTEN and hepatocellular carcinoma.