SHC004-221A1, a novel tyrosine kinase, potently inhibits T315I mutant BCR-ABL in chronic myeloid leukemia.

Although judicious use of tyrosine kinase inhibitors that target BCR-ABL constitutes an effective strategy for the control of chronic myeloid leukemia (CML), drug resistance is observed due to kinase domain mutations, among which a major one is BCR-ABLT315I. In this study, we identified SHC004-221A1 as a potent inhibitor of T315I and other BCR-ABL mutants. Biochemical assays demonstrated that SHC004-221A1 has an inhibitory effect on all selected BCR-ABL mutants. In vitro studies showed that SHC004-221A1 inhibited the proliferation of tumor cell lines carrying native and T315I mutant BCR-ABL. Signaling pathway analysis revealed that SHC004-221A1 inhibited the phosphorylation of STAT5 and CrkL, which contributed to the apoptosis of CML cells. In vivo studies indicated that SHC004-221A1 suppressed BCR-ALBT315I-driven tumor growth in mice. Taken together, the results of this study suggested that SHC004-221A1 may be a promising BCR-ABLT315I inhibitor for the treatment of CML.