HDAC9 and chronic myelogenous leukemia, BCR-ABL1 positive: To conclude, the cell differentiation induced by I13 is likely due to the block of the chronic myeloid leukemia signaling pathway via the modulation of BCR-ABL, which is mediated by the inhibition of HDAC activity and presented by the increase of the acetylation of histones H3 and H4 in CML cells harboring BCR-ABL-T315I.