中文摘要：

目的观察微小RNA-218（miR-218）靶定SOX5对胶质瘤细胞生长和侵袭的影响。方法培养U87胶质瘤细胞株，将其分为对照组、无义序列组和miR-218转染组。取40例胶质瘤组织标本，35例正常脑组织。利用生物信息学方法、荧光素酶报告系统验证SOX5是miR-218的直接作用靶点。通过RT—PCR和Westernblot方法检测U87细胞、胶质瘤组织及其正常脑组织中miR-218对SOX5mRNA和蛋白表达的影响。在U87细胞中过表达miR．218后，利用MTT实验、Tanswell实验检测U87细胞表型的变化。利用RNA干扰技术沉默SOX5，利用MTY实验、Tanswell实验检测U87细胞表型的变化。结果与对照组、无义序列组比较，miRNA-218转染组的miRNA-218相对表达量升高42．2倍；MTT法结果显示，过表达miRNA-218后，胶质瘤细胞生长明显受到抑制，第5天细胞增殖率仅为49．2％；Transwell法结果显示，miRNA一218组穿过Transwell小室的细胞数为（13．0±2．1）个，低于对照组和无义序列组的（35．0±2．3）个和（32．0±3．1）个（均P〈0．05）。生物学信息预测SOX5是miR-218的靶基因之一，在SOX53’端非编码区含有miR-218的结合位点；双荧光素酶实验提示，SOX5为miR．218的直接作用靶点。过表达miR-218后，RT-PCR和Westernblot检测显示，miR-218转染组SOX5mRNA和蛋白的表达明显低于对照组和无义序列组，差异有统计学意义（P〈0．01）。与正常脑组织比较，胶质瘤组织中miRA-218mRNA的相对表达量降低，而SOX5mRNA相对表达量升高（P〈0．01）。沉默SOX5后，MTF法结果显示，细胞培养第5天，SOX5沉默[小干扰RNA（siRNA）-SOX5]组细胞增值率仅为siControl（无序列）组的51．0％；Transwell法分析显示，SOX5沉默组穿过Transwell小室的细胞数为（12．0±1．3）个，低于siControl组的（23．0±2．0）个（P〈0．05）。结论SOX5是miR-218的靶基因，并受其负向调控。miR-218可能通过靶定SOX5在胶

英文摘要：

Objective To observe effect of microRNA-218 （miR-218） targeting SOX5 on the growth and invasiveness of glioblastoma cells. Methods U87 glioma cell lines were cultured, and they were divided into a control group, a nonsense sequence group and a miR-218 mimics transfection group. Forty glioma tissue specimens and 35 normal brain tissue samples were selected. The biological information method and the luciferase report system were used to verify that SOX5 was the direct acting target of miR- 218. The effect of miR-218 on mRNA and protein expression Qf SOX5 in U87 cells, glioma tissue and their normal brain tissue were detected by RT-PCR and Western blot. After overexpressing miR-218 in U87 cells, the changes of U87 cell phenotype were detected by using the MTT experiment and Tanswell experiment. Results Compared with the control and the nonsense sequence groups, the relative expression quantity of miRNA-218 increased about 42.23 times in the miRNA-218 mimics transfection group. The results of MTT assay showed that the growth of glioma cells was inhibited significantly after overexpreesing miRNA-218. The cell proliferation rate of at day 5 was only 49.2%. The results of Transwell assay showed that the number of cells passing through the Transwell chambers was 13.0±2.1. It was lower than 35.0±2.3 and 32.0±3.1 in the control and the nonsense sequence groups （ all P 〈 0.05 ）. The biological information predicted that the SOX5 was one of the target genes of miR-218. UTR contained the binding site of miR-218 in SOX5 3＇. The dual luciferase assays indicated that SOX5 was the direct acting target of miR-218. After overexpressing miR-218, RT-PCR and Western blot showed that the expression of SOX5 mRNA and protein in the miR-218 mimics transfection group was significantly lower than that the control and the nonsense sequence groups. There was significant difference （P 〈 0.01 ）. After silencing SOX5, the results of the MTT assay showed that the cell increment rate of the siRNA-SOX5 group at day 5 of cell cu