TCTP在辐射诱导胶质瘤细胞旁效应中的作用及机制研究

目的:研究肿瘤翻译控制蛋白(TCTP)在辐射诱导胶质瘤细胞旁效应中的作用及机制。方法:给予不同剂量的X射线照射U87、SHG44两种胶质瘤细胞,观察U87以及SHG44细胞的克隆形成率,并在给予最佳照射剂量后,通过Western Blot检测TCTP蛋白表达水平。将经过最佳X射线照射剂量的U87以及SHG44两种胶质瘤细胞与未经过辐射照射的细胞放在一起共培养,通过MTT实验检测胶质瘤细胞的增殖率,Western Blot检测共培养的胶质瘤细胞与经过辐射的胶质瘤细胞中Caspase3蛋白表达水平。结果:U87以及SHG44两种胶质瘤细胞的克隆形成率随着X射线照射剂量增加而显著性降低(P0.05),给予最佳X射线照射剂量后,与未经过X射辐射照射后的细胞相比,其TCTP蛋白表达水平明显升高(P0.05)。经过辐射照射与未经过辐射照射的胶质瘤细胞经过共培养后,与经过辐射的胶质瘤细胞相比,细胞的增殖率明显升高,同时共培养的胶质瘤细胞与经过辐射的胶质瘤细胞相比,Caspase3的蛋白表达明显降低(P0.05)。结论:TCTP的表达增高能够诱导未经过辐射的U87以及SHG44两种胶质瘤细胞的抗凋亡作用增强,其作用机制可能与Caspase3的表达降低有关。

Effects and Mechanisms of Translationally Controlled Tumor Protein in the Radiation-induced Bystander Effect of Glioma Cells

ABSTRACT Objective: To study the protective effects and the mechanism of Translationally Controlled Tumor Protein in the radia- tion-induced bystander effect of glioma cells. Methods: The colony formation of U87 and SHG44 cells treated by different doses of radia- tion were detected, and western blot was used to analyze the expression of TCTP after the treatment by optimal dose of radiation. The glioma cells of U87 and SHG44 which were treated by optimal dose of radiation were co-cultured with the glioma cells of U87 and SHG44 which hadn''t been treated by the radiation. The changes of relative cell proliferation of U87 and SHG44 after the radiation were detected through MTT assay, and western blot was used to analyze the expression of Caspase3 between the co-cultured and the radiation of glioma cells on U87 and SHG44. Results: In the glioma cells of U87 and SHG44, the colony formation was significantly decreased with the increase of X ray radiation dose (P<0.05). After being treated by optimal dose of radiation, the expression of TCTP was signifi- cantly increased compared with the glioma cells of U87 and SHG44 which hadn''t been treated by the radiation (P<0.05). After co-cul- tured the glioma cells of U87 and SHG44 which were treated by optimal dose of radiation and the glioma cells of U87 and SHG44 which hadn''t been treated by the radiation, the relative cell proliferation was significantly increased compared with the glioma cells of U87 and SHG44 which were treated by optimal dose of radiation, and meanwhile the expression of Caspase-3 was significantly reduced (P<0.05). Conclusion: Increase the expression of TCTP could induce the anti-apoptotic effect of glioma cells of U87 and SHG44 which hadn''t been treated by the radiation, and the mechanism might be related to the expression of Caspase-3.