Targeting HSP90 dimerization via theC terminus is effective in imatinib-resistant

Heat shock protein 90 (HSP90) stabilizes many client proteins, including the BCR-ABL1

oncoprotein. BCR-ABL1 is the hallmark of chronic myeloid leukemia (CML) in which
treatment-free remission (TFR) is limited, with clinical and economic consequences. Thus,
there is an urgent need for novel therapeutics that synergize with current treatment
approaches. Several inhibitors targeting the N-terminal domain of HSP90 are under investigation, but side effects such as induction of the heat shock response (HSR) and toxicity
have so far precluded their US Food and Drug Administration approval. We have developed a novel inhibitor (aminoxyrone [AX]) of HSP90 function by targeting HSP90 dimerization via the C-terminal domain.