CDKN1A and malignant colon neoplasm: In addition to colon cancer, it has been reported that 5-aza-CdR increases p53/p21Waf1/Cip1 expression in lung cancer and prostate cancer [9,10], p27kip1 in esophageal squamous cell carcinoma [11], and p57KIP2 in lung and breast cancers [12].