Currently two DNMT inhibitors (DNMTi), 5-azacytidine (azacitidine) and 5-aza-2′-deoxycytidine (decitabine) have been approved by Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), and chronic myelomonocytic leukemia (CMML) (Constantinides et al., 1978; Jones et al., 2019). This evidence concerns the gene DNMT1 and chronic myelomonocytic leukemia.