Table 2.

Enzymes related to DNA modification and their functions

	Methylase/ demethylase	Downstream targets	Functions	References
DNA methylation	DNMT1	ADAM23, Hint1, RASSF1A, and RECK	Affects the proliferation, G0/G1 cell cycle arrest and invasion of CRC cells	[121]
		Socs3	Affects the migration and invasion of SW620 cells induced by IL-23	[122]
	DNMT1 and DNMT3b	MEG3-DMR	DNMT1/DNMT3b double knockout increases 14q32 miRNAs expression and inhibits CRC liver metastasis	[119]
		E-cadherin, MGMT and P16	Affects the proliferation, migrative and invasive ability and chemosensitivity of CRC cells	[120]
		CXCL12	Ablation of both DNMT1 and DNMT3b restores CXCL12 expression and further reduces metastatic tumor formation in mice	[123]
DNA demethylation	TET1	VEGF, Glut1, EPO	Mediates the binding of HIF-1α to HREs of these target genes and increases the migration ability of CRC cells	[131]