Mian, Afsar AliHaberbosch, IsabellaKhamaisie, HazemAgbarya, AbedPietsch, LarissaEshel, ElizabehNajib, DallyChiriches, ClaudiaOttmann, Oliver GerhardHantschel, OliverBiondi, Ricardo M.Ruthardt, MartinMahajna, Jamal2021-07-032021-07-032021-07-032021-06-1010.1007/s00277-020-04357-zhttps://infoscience.epfl.ch/handle/20.500.14299/179752WOS:000659803200001Resistance remains the major clinical challenge for the therapy of Philadelphia chromosome-positive (Ph+) leukemia. With the exception of ponatinib, all approved tyrosine kinase inhibitors (TKIs) are unable to inhibit the common "gatekeeper" mutation T315I. Here we investigated the therapeutic potential of crizotinib, a TKI approved for targeting ALK and ROS1 in non-small cell lung cancer patients, which inhibited also the ABL1 kinase in cell-free systems, for the treatment of advanced and therapy-resistant Ph+ leukemia. By inhibiting the BCR-ABL1 kinase, crizotinib efficiently suppressed growth of Ph+ cells without affecting growth of Ph- cells. It was also active in Ph+ patient-derived long-term cultures (PD-LTCs) independently of the responsiveness/resistance to other TKIs. The efficacy of crizotinib was confirmed in vivo in syngeneic mouse models of BCR-ABL1- or BCR-ABL1(T315I)-driven chronic myeloid leukemia-like disease and in BCR-ABL1-driven acute lymphoblastic leukemia (ALL). Although crizotinib binds to the ATP-binding site, it also allosterically affected the myristol binding pocket, the binding site of GNF2 and asciminib (former ABL001). Therefore, crizotinib has a seemingly unique double mechanism of action, on the ATP-binding site and on the myristoylation binding pocket. These findings strongly suggest the clinical evaluation of crizotinib for the treatment of advanced and therapy-resistant Ph+ leukemia.Hematologycrizotinibphiladelphia chromosome-positive leukemiabcr-abl1tki resistanceallosteric inhibitioncompound mutationskinasemutationsdomainsitebcrtext::journal::journal article::research article