CRC tissues with the repression of PEPT1 had higher levels of DNA methylation in the sequenced region (−264 bp to +36 bp) compared with adjacent non-tumor colonic tissue samples, especially in the 25th to 30th CpG sites, suggesting that hypermethylation occurs at the PEPT1 promoter in CRC (Fig. 3C). Here, SLC15A1 is linked to colorectal carcinoma.