APC and colorectal carcinoma: The Wnt/β-catenin pathway is central to CRC, with the initial step in carcinogenesis determined to be mutations in the adenomatous polyposis coli gene, which then results in the activation of β-catenin, a transcription factor critical in the maintenance of the normal intestinal stem cell compartment as well as the cells-of-origin or carcinoma-initiating cells (CICs) for CRC (6–8).