CDKN2A and malignant colon neoplasm: The antibodies used in this study were the following: 1) p16Ink4a, which is an important factor in carcinogenesis and was shown to be linked to oncogene-induced senescence in the serrated route to colon cancer [14]; 2) Ki67, which represents a established proliferation marker; 3) α-methylacyl-coenzyme A racemase (AMACR;p504s).