CBL and chronic myelogenous leukemia, BCR-ABL1 positive: Furthermore, we identify the E3 ubiquitin ligase c-cbl as a candidate intermediate that drives TGFβ-mediated Lyn turnover/activation, and show that blocking TGFβ signalling activity reduces Lyn activity and concomitantly sensitizes CML cells to imatinib-mediated cell death.