谷氨酰胺酶2对肝内胆管细胞癌细胞增殖和侵袭能力的影响及机制

Effect of glutaminase 2 on the proliferation and invasion ability of intrahepatic cholangiocarcinoma cells and its mechanism

目的探讨谷氨酰胺酶2(GLS2)对肝内胆管细胞癌细胞增殖和侵袭能力的影响及其机制。方法将对数生长期人肝内胆管细胞癌RBE细胞随机分为空白对照组(Con组)、GLS2过表达阴性对照组(pcDNA-NC组)、pcDNA-GLS2组和pcDNA-GLS2+磷酸化蛋白酪氨酸激酶(p-JAK)组。Con组RBE细胞不转染任何质粒,pcDNA-NC组RBE细胞转染pcDNA-NC质粒,pcDNA-GLS2组RBE细胞转染pcDNA-GLS2质粒,pcDNA-GLS2+p-JAK组RBE细胞转染pcDNA-GLS2质粒并和p-JAK多肽共培养。采用实时荧光定量聚合酶链反应法检测各组细胞中GLS2 mRNA的相对表达量,细胞计数试剂盒-8检测各组细胞增殖能力,流式细胞术检测各组细胞凋亡情况,Transwell小室实验检测各组细胞侵袭能力,Western blot法检测细胞中蛋白酪氨酸激酶2(JAK2)、p-JAK2、信号转导子与转录激活子3(STAT3)、磷酸化信号转导子与转录激活子3(p-STAT3)蛋白相对表达量。结果pcDNA-GLS2组细胞中GLS2 mRNA的相对表达量显著高于Con组和pcDNA-NC组(P<0.05);pcDNA-GLS2+p-JAK组细胞中GLS2 mRNA的相对表达量显著低于pcDNA-GLS2组(P<0.05)。pcDNA-GLS2组细胞存活率显著低于Con组(P<0.05);与pcDNA-GLS2组相比,pcDNA-GLS2+p-JAK组细胞存活率显著增加(P<0.05)。与Con组相比,pcDNA-GLS2组细胞凋亡率显著增加(P<0.05);pcDNA-GLS2+p-JAK组细胞凋亡率显著低于pcDNA-GLS2组(P<0.05)。pcDNA-GLS2组细胞迁移数显著低于Con组(P<0.05);与pcDNA-GLS2组相比,pcDNA-GLS2+p-JAK组细胞迁移数显著增加(P<0.05)。与Con组相比,pcDNA-GLS2组细胞中p-JAK2/JAK2、p-STAT3/STAT3比值显著降低(P<0.05);pcDNA-GLS2+p-JAK组细胞中p-JAK2/JAK2、p-STAT3/STAT3比值显著高于pcDNA-GLS2组(P<0.05)。结论过表达GLS2可通过抑制JAK2/STAT3信号通路调控肝内胆管癌细胞生物学活性,抑制肝内胆管癌RBE细胞增殖、侵袭、迁移能力,诱导细胞凋亡。

Objective To investigate the effect of glutaminase 2(GLS2)on the proliferation and invasion ability of intrahepatic cholangiocarcinoma cells and its mechanism.Methods Human intrahepatic cholangiocarcinoma RBE cells in the logarithmic phase were randomly divided into a blank control group(Con group),a GLS2 overexpression negative control group(pcDNA-NC group),a pcDNA-GLS2 group,and a pcDNA-GLS2+phosphorylation Janus kinase(p-JAK)group.RBE cells in the Con group did not transfect any plasmid;RBE cells in the pcDNA-NC group were transfected with pcDNA-NC plasmid;RBE cells in the pcDNA-GLS2 group were transfected with pcDNA-GLS2 plasmid;RBE cells in the pcDNA-GLS2+p-JAK group were transfected with pcDNA-GLS2 plasmid and co-cultured with p-JAK peptide.Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression of GLS2 mRNA in each group of cells;cell counting kit-8 was used to detect the proliferation ability of cells in each group;flow cytometry was used to detect the apoptotic ability of cells in each group;Transwell assay was used to detect the invasion ability of cells in each group;Western blot was used to detect the relative expression levels of Janus kinase 2(JAK2),phosphorylation JAK2(p-JAK2),signal transducer and activator of transcription 3(STAT3),and phosphorylation STAT3(p-STAT3)proteins in cells.Results The relative expression level of GLS2 mRNA in the pcDNA-GLS2 group was significantly higher than that in the Con group and pcDNA-NC group(P<0.05);the relative expression level of GLS2 mRNA in the pcDNA-GLS2+p-JAK group was significantly lower than that in the pcDNA-GLS2 group(P<0.05).The survival rate of cells in the pcDNA-GLS2 group was significantly lower than that in the Con group(P<0.05),and compared with the pcDNA-GLS2 group,the survival rate of cells in the pcDNA-GLS2+p-JAK group was significantly increased(P<0.05).Compared with the Con group,the apoptosis rate of cells in the pcDNA-GLS2 group significantly increased(P<0.05);the apoptosis rate of cells in the pcDNA-GLS2+p-JAK group was significantly lower than that in the pcDNA-GLS2 group(P<0.05).The migration number of cells in the pcDNA-GLS2 group was significantly lower than that in the Con group(P<0.05);compared with the pcDNA-GLS2 group,the pcDNA-GLS2+p-JAK group showed a significant increase in the cell migration number(P<0.05).Compared with the Con group,the p-JAK2/JAK2 and p-STAT3/STAT3 ratios in the pcDNA-GLS2 group were significantly reduced(P<0.05);the p-JAK2/JAK2 and p-STAT3/STAT3 ratios in the pcDNA-GLS2+p-JAK group were significantly higher than those in the pcDNA-GLS2 group(P<0.05).Conclusion Overexpression of GLS2 can regulate the biological activity of intrahepatic cholangiocarcinoma cells by inhibiting the JAK2/STAT3 signaling pathway,inhibit the proliferation,invasion and migration of intrahepatic cholangiocarcinoma RBE cells,and induce the cell apoptosis.