LATS2对恶性周围神经鞘瘤细胞的调控作用及分子机制探讨

Regulatory effect and molecular mechanism of LATS2 on malignant peripheral nerve sheath tumor cells

目的:探讨大肿瘤抑制激酶2(LATS2)对恶性周围神经鞘瘤(MPNST)细胞增殖和迁移的影响及机制。方法:LATS2过表达慢病毒感染ST88-14、STS26T细胞,实验分为阴性对照组及LATS2过表达组,利用CCK-8、细胞划痕实验检测过表达LATS2对细胞增殖、迁移的影响。实时荧光定量RT-PCR和免疫印迹实验检测细胞中LATS2、多梳抑制复合物2(PRC2)核心组分、Yes相关蛋白(YAP)、含有PDZ结合位点的转录共激活因子(TAZ)的mRNA和蛋白表达,以及组蛋白H3第27位赖氨酸上的三甲基化(H3K27me3)水平。结果:与对照组相比,LATS2过表达抑制ST88-14、STS26T细胞增殖(t=4.219、14.66、11.5,均P<0.05;t=5.674、7.118、10.77,均P<0.01)、迁移(t=4.838、4.736,均P<0.01)。与对照组相比,LATS2过表达不影响ST88-14、STS26T细胞中YAP/TAZ的mRNA和总蛋白水平,但升高其蛋白磷酸化水平(t=6.233、3.759,均P<0.01;t=3.44、2.947,均P<0.05)。与对照组相比,LATS2过表达不影响ST88-14、STS26T细胞中PRC2核心组分SUZ12、EZH2、EED的mRNA和蛋白水平,但H3K27me3水平明显升高(t=6.569、16.68,均P<0.01)。结论:LATS2在MPNST细胞系中表达下降,过表达LATS2升高H3K27me3表达水平,同时促进YAP/TAZ的磷酸化,从而抑制MPNST细胞的增殖、迁移,在MPNST中发挥肿瘤抑制因子的作用。

Objective:To investigate the effect and mechanism of large tumor suppressor kinase 2(LATS2)on the proliferation and migration of malignant peripheral never sheath tumor(MPNST)cells.Methods:LATS2 overexpressing lentivirus was infected with ST88-14 and STS26T cells,and the experiment was divided into negative control group and LATS2 overexpressing group,and the effect of LATS2 overexpression on cell proliferation and migration was detected using CCK-8 assay and cell scratch assay.Real-time fluorescence quantitative(RT-PCR)and Western blotting assays were performed to detect the mRNA and protein expression levels of LATS2,core fraction of polycomb repressive complex 2(PRC2),Yes-associated protein(YAP),transcriptional co-activator with PDZ-binding motif(TAZ),and the trimethylation level on lysine 27 of histone H3(H3K27me3)in the cells.Results:Compared with the control group,LATS2 overexpression inhibited the proliferation(t=4.219,14.66,11.5,all P<0.05;t=5.674,7.118,10.77,both P<0.01)and migration(t=4.838,4.736,both P<0.01)of ST88-14 and STS26T cells.Compared with the control group,LATS2 overexpression did not affect the mRNA and total protein levels of YAP and TAZ in ST88-14 and STS26T cells,but elevated their protein phosphorylation levels(t=6.233,3.759,both P<0.01;t=3.44,2.947,both P<0.05).Compared with the control group,LATS2 overexpression did not affect the mRNA and protein levels of PRC2 core components SUZ12,EZH2 and EED in ST88-14 and STS26T cells,but H3K27me3 protein levels were significantly higher(t=6.569,16.68,both P<0.01).Conclusion:LATS2 expression is decreased in MPNST cell lines,and overexpression of LATS2 increases the expression level of H3K27me3,while promoting the phosphorylation of YAP/TAZ,thus inhibiting the proliferation and migration of MPNST cells and acting as a tumor suppressor in MPNST.