miR-206靶向MAPK-1通路增强胶质瘤细胞放射敏感性

目的 研究miR-206对胶质瘤细胞放射敏感可能作用的信号通路,为深入研究其调控机理奠定基础。方法 将miR-206模拟剂或miR-206抑制剂转染到胶质瘤U87细胞中,使用抑制剂PD98059抑制MAPK通路活性并照射处理细胞,MTT和克隆形成实验检测细胞放射敏感性变化。分别用qRT-PCR和蛋白印迹法检测miR-206和MAPK1的表达变化,TargetScan软件预测和双荧光素酶报告实验验证miR-206和MAPK1的相互作用。结果 胶质瘤细胞放射处理后miR-206表达下调,MAPK1表达上调。miR-206模拟剂过表达miR-206,细胞增殖和克隆形成能力下降,放射敏感性增高;转染抑制剂抑制miR-206表达,细胞增殖和克隆形成能力加强,放射敏感性降低。使用TargetScan软件查找发现MAPK1可能是miR-206的靶基因,双荧光素酶报告实验进一步验证了miR-206和MAPK1具有相互作用。过表达或降低miR-206表达,MAPK1与miR-206呈相反变化趋势。使用抑制剂抑制MAPK信号通路,胶质瘤细胞放射敏感性升高。结论 miR-206可能靶向MAPK1,通过抑制MAPK信号通路活性调节胶质瘤细胞的放射敏感性。

miR-206 enhances radiosensitivity of glioma cells by targeting MAPK1 pathway

Objective To investigate the signaling pathway probably targeted by miR-206 in regulation of the radiosensitivity of glioma cells,and to provide a basis for further understanding of its regulatory mechanism.Methods The miR-206 mimic or miR-206 inhibitor was transfected into U87 glioma cells.The activity of the MAPK pathway was inhibited by PD98059.The cells were exposed to radiation.MTT assay and colony formation assay were used to determine the changes in the radiosensitivity of cells.Quantitative RT-PCR and Western blot were used to determine the expression of miR-206 and MAPK1,respectively.TargetScan prediction and dual luciferase reporter system were used to verify the interaction between miR-206 and MAPK1.Results After exposure to radiation,the glioma cells had downregulated expression of miR-206 and upregulated expression of MAPK1.Overexpression of miR-206 induced by the miR-206 mimic reduced cell proliferation and colony formation ability and enhanced the radiosensitivity;inhibition of miR-206 expression by the miR-206 inhibitor reversed the effects of the miR-206 mimic.MAPK1 was predicted to be the possible target gene of miR-206 by TargetScan software.The dual luciferase reporter assay further confirmed the interaction between miR-206 and MAPK1.The expression of MAPK1 was negatively correlated with that of miR-206.The radiosensitivity of glioma cells was enhanced when the MAPK pathway was blocked by the inhibitor.Conclusions miR-206 probably targets MAPK1.It may regulate the radiosensitivity of glioma cells by inhibiting the activity of the MAPK signaling pathway.