miR-361-5p负调控靶基因FoxM1增加骨肉瘤细胞放射敏感性研究

目的 探讨miR-361-5p对骨肉瘤细胞放射敏感性的影响及其可能的下游调控机制。方法 构建放射抵抗的骨肉瘤细胞系HOS-R,利用RT-qPCR检测miR-361-5p在HOS和HOS-R细胞中的表达情况;上调或下调miR-361-5p表达、敲低FoxM1,以克隆形成实验和流式细胞术检测miR-361-5p对HOS-R细胞存活率和细胞凋亡率,通过双荧光素报告基因实验和蛋白免疫印迹实验检测miR-361-5p与FoxM1的靶向关系。构建FoxM1过表达载体,采用克隆形成实验和流式细胞术检测miR-361-5p通过FoxM1对骨肉瘤细胞放射敏感性的影响。结果 RT-qPCR检测结果显示,miR-361-5p在HOS-R细胞中低表达。克隆形成实验和流式细胞术检测结果显示,过表达miR-361-5p可显著降低HOS-R细胞的生存率,增加其细胞凋亡率,与敲低FoxM1结果相反。双荧光报告基因实验证实miR-361-5p靶向负性调控FoxM1表达,FoxM1可逆转miR-361-5p对细胞HOS-R放射敏感性的促进作用。结论 miR-361-5p可负调控FoxM1,并影响骨肉瘤细胞的放射敏感性。

Mir-361-5p enhances radiosensitivity of osteosarcoma cells by directly downregulating FOXM1

Objective To investigate the effect of microRNA361-5p on radiosensitivity of osteosarcoma cells and its downstream regulatory mechanisms.Methods The radioresistant osteosarcoma cell line HOS-R was constructed and the expression of microRNA-361-5p in HOS and HOS-R cells was detected by RT-qPCR.The survival rate and apoptosis rate were detected by clone formation assay and flow cytometry in HOS-R cells treated with up-regulated or down-regulated of miR-361-5p,or FOXM1 depletion. Dual fluorescent luciferase reporter and western blot assays were used to measure the relationship between miR-361-5p and FOXM1.he effects of miR-361-5p on radiosensitivity of osteosarcoma cells were determined by cloning formation assay and flow cytometry.Results RT-qPCRResults showed that miR-361-5p was low expressed in HOS-R cells. Colony formation and flow cytometry assays demonstrated that overexpression of miR-361-5p significantly decreased the survival rate and increased the apoptosis rate of HOS-R cells. In contrast,FOXM1 downregulation inhibited cell survival rate and induced apoptosis. Moreover,miR-361-5p negatively regulated FOXM1 expression. Besides,FOXM1 overexpression attenuated the miR-361-5p upregulation-mediated promotion of radiosensitivity in HOS-R cells.Conclusion miR-361-5p was involved in the radiosensitivity of osteosarcoma cells by inhibiting FOXM1.