In order to connect IMP2, AFP, and DLK1 overexpression to already known molecular subsets of HCC,16 we performed hierarchical clustering of data set GSE14520 according to the marker genes identified by Hoshida et al.17 for three HCC subtypes in mouse and by Chiang et al.18 for five HCC subtypes in human (Supplementary Figure S1). This evidence concerns the gene DLK1 and hepatocellular carcinoma.