Dasatinib inhibits the proliferation of chronic lymphocytic leukemia cells and function of BTKC481S in vitro
Objective To investigate the effect of dasatinib(BMS-354825)on the proliferation of chronic lymphocytic leukemia(CLL)cell lines and the activation and function of wild-type/ibrutinib-resistant bruton tyrosine kinase(BTK)in vitro.Methods The inhibitory effect of dasatinib at different concentrations on the proliferation of CLL cell lines were observed.After transfection of indicated plasmids(wild-type BTK and its mutants BTKC481S,BTKT474F and BTKT474I/C481S)and treatment with dasatinib and ibrutinib,the phosphorylation levels of BTK and its initial downstream target PLCγ2 were measured by Western blot.Results The proliferation of CLL cell lines MEC-1 and JVM3 cells were significantly inhibited by dasatinib in a dose-dependent manner with an IC50 value of 3.54 mol/L and 0.65 mol/L,respectively.The phosphorylation of wild-type BTK and PLCγ2 was inhibited by 0.5 mol/L ibrutinib and 0.2 mol/L dasatinib.Upon activation of the BCR signaling,BTKC481S,BTKT474F and BTKT474I/C481S were functionally activated and phosphorylated its downstream target PLCγ2.All the mutations were resistant to ibrutinib at physical concentrations.Furthermore,0.5 mol/L dasatinib inhibited the activation of BTKC481S followed by inhibition of PLCγ2 activation,but did not suppress the activation of BTKT474F and BTKT474I/C481S,which suggested that dasatinib might overcome BTKC481S-induced resistance to ibrutinib,without effect on"gatekeeper"BTK alterations.Conclusions Dasatinib inhibits the activation and function of both wild-type BTK and BTKC481S and hence inhibits the proliferation of CLL cells,which is promising to overcome ibrutinib resistance caused by BTKC481S.
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NSTL
万方数据
维普
