Work

Hsp70-Bim interaction mediated mitophagy as a potential therapeutic target for CML stem cells

Year: 2025

Type: article

Abstract: In chronic myeloid leukemia (CML), disease persistence in patients is maintained by leukemic stem cells (LSCs), which drive tyrosine kinase inhibitor (TKI) resistance. Autophagy has been proposed as a potential therapy to eradicate CML LSCs. Here, using a small-molecule inhibitor of Hsp70 (heat shock protein 70)-Bim (Bcl-2-interacting mediator of cell death) interaction, S1-10, we demonstrate that Hsp70-Bim is a target for CML stemness maintenance. Hsp70-Bim is driven by Bcr-Abl and mediates particularly stronger mitophagy in CML LSCs than differentiated CML cells and HSCs. The more selective mitophagy regulation of Hsp70-Bim than ULK1 (unc-51-like autophagy activating kinase 1) is illustrated. Pharmacological inhibition of Hsp70-Bim blocks mitophagy, leading to the differentiation of CML LSCs, loss of quiescence, and loss of LSC self-renewal potential. In the patient-derived xenograft (PDX) CML models, S1g-10 reduces the number of LSCs by more than 80% after two weeks of injection, without obvious toxicity on normal red blood cells.

Source: Stem Cell Reports

DOI: 10.1016/j.stemcr.2025.102751