H19 and cancer: The most frequently epimutated regions varied depending on tissue origin, with the maternally methylated ZNF597 DMR being affected in 66.6% of hepatocarcinoma cell lines, H19 in 28.9 % of lung, ZNF331 DMR1 in 32% of colon and GRB10 in 44.9% of breast-derived cancer cell lines.