Effect of PI3K/Akt/mTOR signal pathway-mediated N822K mutation on apoptosis induced by c-KIT inhibitor in AML cells / 中国免疫学杂志

ABSTRACT

Objective:To investigate the effect of c-KIT N822K mutation on the apoptosis of AML cells induced by c-KIT inhibitor and to explore the underlying molecular mechanisms.Methods: Kasumi-1 cells that carry the c-KIT N822K mutation were used as experimental group,and HL-60 and NB4 cells with non-c-KIT N822K mutation were used as control group.These AML cells were treated with 0,0.04,0.16 and 0.64 μmol/L c-KIT inhibitor sunitinib for 24 h,respectively.Apoptosis-related proteins and PI3K/Akt/mTOR pathway proteins were detected by Western blot,compared the changes of cell-related signal pathway proteins in each group.Results: With the increase of sunitinib concentration,the expression of apoptosis-related proteins Bax,CytoC,Caspase-9, Actived-Caspase-3 and PARP in HL-60 and NB4 cells were increased (P<0.05),and the expression of anti-apoptotic protein Bcl-2 was down-regulated (P<0.01).However,the trend of this change was obviously weakened in Kasumi-1 cells with N822K mutation.In Kasumi-1 cells,the phosphorylation levels of PI3K/Akt/mTOR pathway proteins such as PI3K,Akt,4EBP1 and mTOR were down-regulated in a dose-dependent manner(P<0.05),but not in HL-60 cells and NB4 cells.Conclusion:The constitutive activation of c-KIT induced by N822K mutation may affect the apoptosis induction of c-KIT inhibitor sunitinib to Kasumi-1 cells,which may be related to the inhibition of PI3K/Akt/mTOR pathway.