RASSF1 and hepatocellular carcinoma: In a more focused study, tumor suppressor genes were identified that are hypermethylated in the early stages of HCC.16 Eight genes (HIC1, GSTP1, SOCS1, RASSF1, CDKN2A, APC, RUNX3 and PRDM2) displayed significantly increased methylation in early HCCs and were associated with shorter-time-to-HCC occurrence.