金葡菌杀白细胞素S组分LukS-PV抑制急性髓系白血病细胞增殖的机制研究

Study on the Inhibitory Mechanism of Staphylococcus Aureus Leukocidin S Component Luk S-PV on the Proliferation in Acute Myeloid Leukemia Cells

目的 探讨金葡菌杀白细胞素S组分LukS-PV通过下调甲基转移酶SET8对急性髓系白血病(AML)细胞THP-1和HL-60增殖的影响。方法 采用实时荧光定量PCR(qRT-PCR)和Western blot检测不同浓度LukS-PV处理后THP-1和HL-60细胞的SET8 mRNA和蛋白的表达水平。将敲低SET8表达的慢病毒载体转染至THP-1和HL-60细胞中,qRT-PCR和Western blot检测SET8敲低效率,EdU实验检测敲低SET8对细胞增殖的影响。在敲低SET8的基础上,加入LukS-PV处理,通过EdU检测细胞增殖探究LukS-PV是否通过下调SET8抑制白血病细胞THP-1和HL-60的增殖。结果 在AML细胞系THP-1和HL-60中,与PBS对照组相比,LukS-PV处理组SET8及其修饰位点H4K20me1的表达水平明显降低并具有浓度依赖性(P<0.05)。与阴性对照组相比,在THP-1和HL-60细胞转染敲低SET8慢病毒载体后,SET8表达水平明显降低(P<0.05),细胞增殖能力明显降低(P<0.05)。与PBS对照组相比,敲低SET8可抑制细胞增殖(P<0.05),而在此基础上加入LukS-PV处理后,细胞增殖抑制更加明显(P<0.05)。结论 下调SET8抑制AML细胞THP-1和HL-60的增殖;且LukS-PV可以通过下调SET8抑制细胞增殖,发挥抗白血病作用。

Objective To explore the effect of LukS-PV on the proliferation in acute myeloid leukemia(AML)cells THP-1 and HL-60 by down-regulating methyltransferase SET8.Methods Real-time fluorescence quantitative PCR(qRT-PCR)and Western blot were used to detect the expression levels of SET8 mRNA and protein in THP-1 and HL-60 cells after treatment with different concentrations of LukS-PV.The lentiviral vector with knock-down SET8 expression was transfected into THP-1 and HL-60 cells.SET8 knockdown efficiency was detected by qRT-PCR and Western blot,and the effects of SET8 knock-down on cell proliferation was detected by EdU assay.Finally,on the basis of knocking down SET8,adding LukS-PV treatment for detecting cell proliferation by EdU to explore whether LukS-PV inhibits the proliferation of leukemic cells THP-1 and HL-60 by down-regulating SET8.Results In AML cell lines THP-1 and HL-60,the expression of SET8 and H4K20me1 in LukS-PV treated group was significantly lower than that in PBS control group in a concentration-dependent manner(P<0.05).Compared with the negative control group,SET8 expression level was significantly decreased in THP-1 and HL-60 cells transfected with knock-down SET8 lentiviral(P<0.05),and cell proliferation ability showed the same trend(P<0.05).Compared with the PBS control group,knocking down SET8 could inhibit cell proliferation(P<0.05),and the inhibition of cell proliferation was more obvious when LukS-PV was added on this basis(P<0.05).Conclusion Down-regulating SET8 inhibits the proliferation of THP-1 and HL-60 AML cells,and LukS-PV can inhibit cell proliferation by down-regulating SET8 and play an anti-leukemia effect.