Among the genes with the most significantly altered expression in Iqgap2−/− HCC tumors were Pdfa5, Ccnd1, Ccnd2, Fgf21, and E2f7 (up-regulation); and Igfbp2, Igfbp3, and Igfbp5 (down-regulation). This evidence concerns the gene IGFBP5 and hepatocellular carcinoma.