NANOG-positive cells also exhibit enhanced ability of self-renewal, clonogenicity, and initiation of tumors, which are consistent with crucial hallmarks in the definition of CSCs (Shan et al., 2012) and its increased expression in cancer cells is correlated with a worse clinical outcome in hepatocellular carcinoma (HCC) (Shan et al., 2012). This evidence concerns the gene NANOG and cancer.