HSPG2 and hepatocellular carcinoma: Of particular note was, for both genes, the region of differential methylation between the proposed subgroup-2 (PLC/PRF-5, SNU-182) and non-subgroup-2 (HepG2, Huh-7) cell lines corresponded exactly to the region of differential methylation identified in the HCC subgroup-2 primary samples, thus providing good evidence that both PLC/PRF-5 and SNU-182 are likely to be derived from HCC subgroup-2 primary samples (Figure 4).