FTO基因对人脑胶质瘤A172细胞放射敏感性的影响及其机制  

Effects of FTO gene on the radiosensitivity of A172 cells and its mechanism

作　　者：聂亮琴[1] 周菊英[1] 王利利[1] 秦颂兵[1] 徐晓婷[1] 

机构地区：[1]苏州大学附属第一医院,215006

出　　处：《中华放射医学与防护杂志》2015年第4期252-256,共5页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的 通过改变人脑胶质瘤细胞系A172中脂肪量与肥胖相关基因（FTO）的表达,研究FTO基因对细胞放射敏感性的影响及其机制.方法 按FTO表达情况将细胞分为正常表达组（A172）、低表达对照组（A172/NC）、低表达组（A172/siRNA）、高表达对照组（A172/PC）和高表达组（A172/FTO）.Western blot法检测受X射线照射后A172组内FTO蛋白的表达水平;克隆集落形成实验检测5组细胞的放射敏感性;免疫荧光法和Western blot法检测FTO对受照后A172细胞内DNA损伤及损伤修复相关蛋白的影响.结果 A172细胞内FTO蛋白表达水平与照射剂量和照后时间有关;A172/siRNA组和A172/FTO组的放射增敏比（SERD0）分别为1.829、0.812;抑制FTO表达能使γ-H2AX foci数目增加（t=-21.884,P＜0.05）,Ku80和p-p95/NBS1蛋白下调（t=24.731、23.293,P＜0.05）,Rad50蛋白表达上调（=3.140,P＜0.05）;FTO高表达后DNA损伤修复相关蛋白表达结果与前面相反（t=0.642、-8.364、26.829,P＜0.05）.结论 FTO是一种辐射抗性基因.改变FTO表达能显著改变A172细胞的放射敏感性,其机制可能与FTO能调控电离辐射引起肿瘤细胞的原发性损伤、改变照射后DNA损伤修复有关.Objective To evaluate the effect of Fat Mass and Obesity Associated （FTO） gene on radiosensitivity of human glioma cell A172 and investigate its potential mechanism by changing the expression of FTO gene.Methods Cells were divided into five groups according to their FTO protein expression level.The normal expression group was recorded as A172 Group,the low-expression and its negative control group was A172/siRNA and A172/NC Group,and the over-expression and its negative control group was A172/FTO and A172/PC group.FTO protein expressions were assayed by Western blot in A172 Group after irradiation.Clonogenic assay was executed to evaluate the relationship between FTO gene and radiosensitivity.Immunofluorescence and Western blot assay were applied to detect the proteins of DNA damage and repair.Results FTO protein expression level in A172 Group was significantly related to the irradiation dose and the time post-irradiation.The radiosensitization ratio （SERD0） of A172/siRNA and A172/FTO group were 1.829 and 0.812 respectively.Not only the number of γ-H2AX foci increased （t =-21.884,P 〈 0.05） in A172/siRNA 1 h post-irradiation but the decreases of p-p95/NBS1 and Ku80 proteins were also detected （t =24.731,23.293,P 〈 0.05） together with the increase of Rad50 protein （t =3.140,P 〈 0.05）.But the expressions of these proteins in A172/FTO group were opposite to the above phenomenon （t =0.642,-8.364,26.829,P 〈 0.05）.Conclusions FTO gene is a radiation-resistant gene,which may because the regulation of FTO gene could alter the primary injury and DNA damage repair in the irradiated tumor cells.

关 键 词：人脑胶质瘤 放射敏感性 肥胖相关基因 

分 类 号：R739.41[医药卫生—肿瘤] R730.55[医药卫生—临床医学]