miR-205通过靶向调控TBX18抑制神经胶质瘤细胞的侵袭能力

目的:探讨微小RNA-205(miR-205)在神经胶质瘤组织中的表达模式及其在胶质瘤细胞侵袭中的作用及可能机制。方法:用real-time PCR检测配对神经胶质瘤组织中miR-205的表达,同时用免疫组化方法检测配对组织中TBX18蛋白的表达量;用脂质体将miR-205模拟物(miR-205 mimics)、miR-205抑制物(miR-205 inhibitor)以及相应对照(control)导入U251胶质瘤细胞后,Transwell实验检测细胞的侵袭能力变化;生物信息学分析结合萤光素酶报告基因实验观察miR-205对TBX18的靶向调控作用;采用RNA干扰技术下调U251细胞中TBX18的表达,用Transwell实验检测细胞侵袭能力变化。结果:miR-205在82.6%所检测的神经胶质瘤组织中表达下调,而TBX18在神经胶质瘤组织中表达上调,两者表达呈负相关;过表达miR-205使U251细胞的侵袭细胞数下降(P0.01),抑制miR-205表达后U251侵袭细胞数增加(P0.01);miR-205在U251胶质瘤细胞中能直接靶向抑制TBX18的表达,干扰TBX18的表达亦使U251细胞的侵袭细胞数下降(P0.01)。结论:miR-205在神经胶质瘤中表达下调,miR-205可能通过靶向调控TBX18影响胶质瘤细胞的侵袭能力,这将为完善胶质瘤侵袭的分子机制及开发新治疗策略以提高胶质瘤治疗效果提供有力的理论依据。

miR-205 inhibits invasion of glioma cells via targeting TBX18

AIM: To explore the expression pattern of microRNA-205 (miR-205) in glioma tissues and its role in the invasion of glioma cells. METHODS: The expression of miR-205 and TBX18 was detected by real-time PCR and immunohistochemical observation, respectively. Transwell assay was used to examine the invasion change of U251 glioma cells after miR-205 overexpression via miR-205 mimics or decrease in miR-205 expression by miR-205 inhibitor. The target of miR-205 was searched by bioinformatics analysis combined with experimental analysis. The protein level of TBX18 was determined by Western blotting after siRNA transfection and Transwell assay was conducted. RESULTS: miR-205 expression was downregulated in 82.6% of detected glioma tissues and TBX18 was significantly overexpressed in glioma tissues compared with normal tissues. miR-205 overexpression remarkably inhibited the invasion potential of U251 glioma cells with a decrease in the invasive cells (P<0.01), while inhibition of miR-205 significantly enhanced the invasion ability of U251 cells. Mechanically, miR-205 directly targeted TBX18 and downregulation of TBX18 also significantly inhibited the invasion potential of U251 cells with a decrease in the invasive cells (P<0.01). CONCLUSION: miR-205 expression is decreased in glioma, and miR-205 inhibits glioma cell invasion via targeting TBX18. Our research contributes to the mechanisms responsible for glioma invasion and provides theoretical base for developing new therapeutic strategy to treat glioma.