Imatinib Blocks Tyrosine Phosphorylation of Smad4 and Restores TGF-β Growth-Suppressive Signaling in BCR-ABL1-Positive Leukemia

Investigators showed that the oncogenic BCR-ABL1 of chronic myelogenous leukemia and the cellular ABL1 tyrosine kinases phosphorylated and inactivated Smad4 to block antiproliferative TGF-β signaling.