Of particular significance, the p.1125Val>Ala mutation of the APC gene in the CRC cancer patients increased expression levels of not only genes downstream of APC in the Wnt/β-catenin signaling pathway but also a gene upstream of APC, GSK-3β, for feedback, providing further evidence indicating the involvement of the APC gene in the pathogenesis of CRC. This evidence concerns the gene APC and colorectal carcinoma.