New therapeutic approaches are based on the use of demethylating agents, such as 5′-azacytidineand 4-phenilbutyrate, that leads to a decrease of BCR-ABL1 expression and to a decrease in the proliferation rate of Ph+ human CML cell lines [51,52]. Here, ABL1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.