Currently, CCNA1 expression has been illustrated to be downregulated in various tumors, including head and neck squamous-cell cancer (HNSCC) and nasopharyngeal carcinoma; and the promoter of the CCNA1 gene is found to be frequently methylated in colon cancer and HNSCC [14–16]. The gene discussed is CCNA1; the disease is malignant colon neoplasm.