Inhibition of Pellino-1 reverts the progression and tyrosine kinase inhibitor resistance in chronic myeloid leukemia.

BCR-ABL1, derived from structural chromosome rearrangements, is the driver mutation in chronic myeloid leukemia (CML). Targeting BCR-ABL1 for degradation is an ideal therapeutic strategy for CML, however, the regulatory mechanisms controlling BCR-ABL1 expression in CML remained unclear. Here, we identified PELI1 as a key regulator for maintaining BCR-ABL1 in CML. BCR-ABL1 upregulates PELI1 via the STAT5/FOXP3 pathway, and the increased PELI1 then interacts with and protects BCR-ABL1 from degradation in CML cells. Concurrently, PELI1 functions as a downstream effector to promote CML cell proliferation. Notably, genetic or pharmacological inhibition of PELI1 effectively suppresses the proliferation of both tyrosine kinase inhibitors (TKIs)-sensitive and TKI-resistant CML cells, as well as Leukemia stem cells (LSCs), which consequently ameliorates the disease burden and progression of CML. Collectively, our findings demonstrated that targeting PELI1 is a promising therapeutic strategy for CML that can overcome TKI resistance and eliminates LSCs.