蛋白酶体抑制剂MG132诱导KG-1细胞凋亡的机制研究

Study on the Mechanism of Apoptosis by Proteasome Inhibitor MG132 in Acute Myeloid Leukeima Cell Line KG-1

研究蛋白酶体抑制剂MG132对人急性髓性白血病细胞株KG-1的致凋亡作用及其对细胞内信号传导因子NF-κB与凋亡蛋白PARP表达的影响。采用CCK-8法检测MG132对KG-1细胞增殖的抑制作用;利用Hoechst33342染色法,从形态学上观察凋亡的KG-1细胞;Western blot检测NF-κB活性及与凋亡相关的蛋白变化情况。CCK-8法检测结果表明,MG132能明显抑制KG-1细胞生长,并呈现时间依赖性和浓度依赖性;Hoechst染色和Western blot检测实验证明,MG132诱导KG-1细胞发生凋亡的同时,NF-κB活性明显降低,细胞凋亡蛋白PARP降解为P89蛋白。以上结果显示,MG132能诱导KG-1细胞凋亡,其机制可能与MG132抑制NF-κB信号转导通路,下调NF-κB表达继而增加凋亡蛋白PARP剪切有关。

The study is aimed to explore the apoptosis effect of proteasome inhibitor MG132 on human acute myeloid leukemia（AML） cell line KG-1 and the expression of nuclear factor-kappa B（NF-κB） and the apoptotic signaling pathway protein.CCK-8 assay tests the growth inhibition effect of MG132 on KG-1 cell;the apoptosis of KG-1 cells induced by MG132 is observed through Hoechst 33342 staining under fluorescent microscope;the NF-κB activity and the expression of apoptotic signaling pathway protein are found by Western blot analysis.CCK-8 assay shows that the growth of KG-1 cell was inhibited by MG132 and presented double manners of concentration and time dependence;the Hoechst 33342 staining and Western blot analysis indicated that the activity of NF-κB is decreased by MG132 on KG-1 cell,and the apoptotic signaling pathway protein PARP is cleaved to a 89KD protein.All the results confirmed that MG132 can obviously inhibit the growth of KG-1 cells,and the possible mechanism was that the apoptotic signaling pathway of NF-κB is inhibited by MG132 and the low expression of NF-κB in turn increasing the apoptotic protein PARP cleavage.