[1] Because the dysregulation of DNMT expression and aberrant DNA methylation widely occurs in human malignancies, the strategy to inhibit DNA methylation against cancer has been developed, and DNMT inhibitors (DNMTIs) including decitabine and 5-azacitidine(5-AZA) have been applied to the treatment of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and other malignancies. The gene discussed is DNMT1; the disease is myelodysplastic syndrome.