Nuclear β-catenin could be a treatment target for patients whose chronic myeloid leukaemia (CML) is resistant to tyrosine kinase inhibitors (TKIs) independent of additional BCR–BL1 mutations, US researchers suggest.
“Collectively, our data implicate nuclear β-catenin in intrinsic BCR-ABL1 kinase-independent TKI resistance, but argue against a direct role for β-catenin in BM [bone marrow]-mediated (extrinsic) TKI resistance”, write Michael Deininger, from the University of Utah in Salt Lake City, and co-investigators.
However, writing in Leukemia, they add “the caveat that even primary CML cells cultured ex vivo on primary MSCs [mesenchymal stromal cells] may not fully recapitulate persistent leukemia cells in patients on long-term imatinib therapy, including heterogeneity across patients.”
The team demonstrated that imatinib therapy reduced β-catenin levels in TKI-sensitive cell lines but had no impact on β-catenin in cells lines with either intrinsic or extrinsic BCR-ABL1 kinase-independent TKI resistance, indicating that “imatinib-resistant cells have uncoupled β-catenin expression from BCR-ABL1 activity.”