The HDAC6 inhibitor 7b induces BCR-ABL ubiquitination and downregulation and synergizes with imatinib to trigger apoptosis in chronic myeloid leukemia

•Compound 7b is a selective HDAC6i in CML.•Compound 7b induces BCR-ABL ubiquitination and degradation.•Imatinib-7b combination causes a synergistic anticancer effect in vitro and in vivo.•Imatinib-7b combination reduces the CML CSC population.