In CRC and some CRC cell lines, mRNA expression of TET1 and global 5hmC level were detected lower than normal tissue or normal colon cells [13–17]; TET1 was capable to react with TSGs by depressing DNA methylation [14, 18], suggesting that enhancement of TET1 expression could be a feasible way of preventing methylation of TSGs of CRC. This evidence concerns the gene TET1 and colorectal carcinoma.