CDKN1A and malignant colon neoplasm: Bladder cancer, colon cancer, liver hepatocellular carcinoma, and thyroid carcinoma show a lower CDKN1A expression in tumors, whereas cervical squamous cell carcinoma, lung squamous carcinoma, prostate adenocarcinoma, sarcoma, skin cutaneous carcinoma, and uterine corpus endometrial carcinoma show a higher p21cip1/waf1 encoding mRNA expression in tumors compared to their normal counterparts (Figure 1).