We investigated the DNA methylation of KGs at CpG sites by MethSurv web-tool with TCGA database and bserved that seven KGs (CEMIP, MMP7, CA4, GUCA2B, ZG16, CLCA4, MS4A12) are significantly methylated at CpG sites (Table 5) that may play the vital role in CRC progression. This evidence concerns the gene CA4 and colorectal carcinoma.