Compared with DNMT1 and DNMT3a, DNMT3b was significantly overexpressed in tumor tissues.50 Overexpression of DNMT1, DNMT3a, and DNMT3b has been observed in multiple cancers, including AML, CML, glioma, and breast, gastric, colorectal, hepatocellular, pancreatic, prostate, and lung cancers. This evidence concerns the gene DNMT1 and chronic myelogenous leukemia, BCR-ABL1 positive.