AFP and neoplasm: p62 was previously shown to induce the expression of the imprinted gene IGF2. 10, 13 Another gene of the same imprinted gene cluster,12DLK1, represents a marker of hepatic stem cells.15DLK1 was significantly overexpressed and its promoter was hypomethylated in human tumor tissue compared with normal samples (P=1.3e−7; Figure 1a and b) and strongly correlated with IMP2 (R2=0.548; P<2.2e−16) and AFP (R2=0.535; P<2.2e−16).