ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Given the crucial role of Sp1 in BCR/ABL kinase activity, we employed BORT, a well-established Sp1 inhibitor [19, 20], and found that exposure of CML cells to BORT resulted in impairment of the Sp1-BCR/ABL axis and subsequent suppression of CML cell proliferation.