Among this list of genes that are predicted to be targeted by miR-122, we selected miR-122:Pkm2 pair for an in-depth analysis, because the embryonic isoform of pyruvate kinase (Pkm2) is reported in the literature to be highly expressed in actively proliferating hepatic progenitor stem cells (hepatoblasts), as well as many cancer cells [31]–[34]. This evidence concerns the gene PKM and cancer.