EZH2 and chronic myelogenous leukemia, BCR-ABL1 positive: We next explored the embedded “expression” and “regulation” tracks using UCSC genome browser to further explore if in fact histone modifications such as EZH2 mediated H3K27Me3 is observed on ID4 promoter in cells that lack ID4 expression such as chronic myelogenous leukemia cell line K562 [32].