ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The prognosis of CML patients has been dramatically ameliorated with the introduction of imatinib (IM), the first tyrosine kinase inhibitor (TKI) drug to target BCR–ABL1, thus confirming the integral role of the oncogenic fusion protein in the onset and progression of CML [3,4,5].