APC and colorectal cancer: Somatic mutations inactivating both copies of APC are present in most sporadic colorectal cancers; A germ-line mutation in familial adenomatous polyposis with an 80% to 100% lifetime risk of colorectal cancer. Activation of Wnt signaling due to inability to degrade the β-catenin oncoprotein [27,28,29,30,31].