脑胶质瘤中miR-98的表达及miR-98下调对脑胶质瘤细胞侵袭的促进作用

The expression of miR-98 in glioma and the promotion effect on invasion of glioma cells by miR-98 down-regulation

目的:探讨微RNA(microRNA,miRNA,miR)-98在脑胶质瘤组织中的表达及其对脑胶质瘤U251细胞迁移和侵袭的影响。方法:应用实时荧光定量PCR法检测脑胶质瘤组织和正常脑组织中miR-98的表达。miR-98 inhibitor与野生型核因子κB抑制蛋白激酶ε(inhibitor of nuclear factor kappa B kinase epsilon,IKBKE)3’-端非编码区(untranslated region,UTR)或突变型IKBKE 3’-UTR重组载体共转染后,应用萤光素酶基因报告系统检测miR-98是否与IKBKE基因3’UTR结合。miR-98 inhibitor转染脑胶质瘤U251细胞后,应用实时荧光定量PCR法和蛋白质印迹法检测细胞中miR-98、IKBKE mRNA和IKBKE蛋白的表达,Transwell法检测细胞的迁移和侵袭能力。IKBKE si RNA转染U251细胞后,应用实时荧光定量PCR法检测细胞中miR-98的表达。结果 :脑胶质瘤组织中miR-98的表达水平明显低于正常脑组织(P<0.05)。miR-98 inhibitor和野生型IKBKE 3’-UTR重组载体共转染组U251细胞的荧光强度增强(P<0.05)。miR-98 inhibitor转染后,U251细胞中miR-98的表达下调,而IKBKE mR NA和IKBKE蛋白的表达水平上调(P值均<0.05),U251细胞的迁移及侵袭能力增强(P值<0.05)。抑制IKBKE表达后,U251细胞中miR-98的表达水平无明显变化(P>0.05)。结论 :脑胶质瘤组织中miR-98低表达,miR-98 inhibitor可能通过调控IKBKE而促进脑胶质瘤U251细胞的迁移及侵袭。

Objective： To detect the expression of miR-98 in glioma tissues and investigate the effect of miR-98 on the invasion and migration of human glioma cell line U251.Methods： The expressions of miR-98 in glioma tissues and normalbrain tissues were detected by real-time fluorescent quantitative PCR. After co-transfection with miR-98 inhibitor and wide type inhibitor of nuclear factor kappa B kinase epsilon（IKBKE） 3＇-untranslated region（UTR） or mutation type IKBKE 3＇-UTR recombination vector, the specific binding ability of miR-98 to 3＇-UTR in IKBKE gene was examined by luciferase gene reporter system. The expression levels of miR-98, IKBKE mRNA and IKBKE protein in glioma cell line U251 after transfection with miR-98 inhibitor were measured by real-time fluorescent quantitative PCR and Western blotting, respectively.The abilities of migration and invasion of U251 cells after transfected with miR-98 inhibitor were detected by Transwell assay. The expression of miR-98 in U251 cells after transfection with IKBKE si RNA was detected by real-time fluorescent quantitative PCR.Results： The expression of miR-98 in glioma tissues was lower than that in normal brain tissues（P〈0.05）. The fluorescence intensity of U251 cells co-transfected with miR-98 inhibitor and wide type IKBKE recombination vector was improved（P〈0.05）.The expression of miR-98 was down-regulated, and the expressions of IKBKE mRNA and protein were upregulated in U251 cells after transfection with miR-98 inhibitor（all P〈0.05）. While the abilities of migration and invasion of U251 cells after transfection with miR-98 inhibitor were increased（both P〈0.05）. There was no change of expression of miR-98 in U251 cells after inhibition of IKBKE expression（P〉0.05）.Conclusion： The expression of miR-98 is low in glioma tissues. miR-98 inhibitor may promote the invasion and migration of glioma U251 cells by regulation of IKBKE expression.