miR-137对U87胶质瘤细胞中EZH2表达和细胞增殖的影响

Effects of miR-137 on EZH2 expression and cell proliferation of U87 glioma cells

目的研究miR-137对U87胶质瘤细胞EZH2表达及细胞增殖的影响。方法先用双荧光素酶报告基因检测系统筛选靶向EZH2 3'-非翻译区(3'-UTR)的miRNA,然后采用逆转录聚合酶链反应(RT-PCR)和Western blot检测在胶质瘤细胞中作用最强的miRNA对EZH2 mRNA和蛋白表达的影响,再用MTT法检测该miRNA对U87胶质瘤细胞增殖的影响。结果胶质瘤细胞中低表达的9个miRNA被预测靶向EZH2的3'-UTR。双荧光素酶报告基因检测表明:miR-126、miR-137和miR-138能使荧光素酶活性显著降低,其中miR-137的作用最强(P<0.01)。RT-PCR和Western blot结果也显示miR-137能抑制EZH2 mRNA和蛋白的表达。MTT结果显示:miR-137能抑制U87胶质瘤细胞增殖,过表达EZH2基因可拮抗miR-137对胶质瘤细胞增殖的抑制作用。结论 miR-137可抑制U87胶质瘤细胞增殖,可能与抑制EZH2基因表达有关。

Objective To investigate the effects of miR-137 on EZH2 expression and cell proliferation in U87 glioma cells.Methods Dual-luciferase reporter gene system was used to screen the predicted miRNA targeting 3＇-untranslated region（3＇-UTR） of EZH2 gene.The effects of miRNA on EZH2 mRNA and protein expressions in U87 glioma cells were detected by reverse transcription-polymerase chain reaction（RT-PCR） and Western blot.The effect of miRNA on cell proliferation was detected by MTT assay.Results Nine miRNAs expressed at low level in glioma cells were predicted to target 3＇-UTR of EZH2 gene.Dual-luciferase reporter gene system showed that miR-126,miR-137 and miR-138 significantly decreased the activity of luciferase,and miR-137 resulted in the most significant decrease of luciferase activity（P0.01）.RT-PCR and Western blot results showed that miR-137 inhibited EZH2 mRNA and protein expressions.MTT assay also showed that miR-137 inhibited the proliferation of U87 cells and overexpressed EZH2 gene could antagonize the inhibitory effect of miR-137 on U87 glioma cells.Conclusions miR-137 can inhibit the proliferation of U87 glioma cells,which may be related to the inhibition of EZH2 gene expression.