下调NEK-2表达对人肺癌A549细胞放射敏感性影响  

Effect of down-regulation NEK-2 level on radio-sensitibity of A549 cells

作　　者：陈成龙 彭逸茹 张楠[1] 薛莲[2] 于冬[1] Chen Chenglong;Peng Yiru;Zhang Nan;Xue Lian;Yu Dong(School of Radiation Medicine and Protection,Soochou University 215000;School of Public Health,Soochow University 215000)

机构地区：[1]苏州大学医学部放射医学与防护学院,215000 [2]苏州大学公共卫生学院,215000

出　　处：《中华放射肿瘤学杂志》2019年第2期131-135,共5页Chinese Journal of Radiation Oncology

摘　　要：目的探讨下调NEK-2表达对非小细胞型肺癌A549细胞放射敏感性影响方法培养人非小细胞型肺癌A549细胞,通过siRNA技术沉默A549细胞中NEK-2的表达水平,通过蛋白印迹法实验进行验证。采用克隆形成实验检测放射增敏作用,用流式细胞技术检测下调NEK-2表达对辐射诱导A549细胞凋亡和周期的影响,采用免疫荧光实验检测DNA双链断裂和修复情况。结果NEK-2siRNA可明显下调A549细胞中NEK-2的表达水平。相对于空白对照组和阴性对照组,下调NEK-2表达能抑制肿瘤细胞的增殖能力,提高A549细胞的放射敏感性,平均致死剂量由1.80Gy下降至1.40Gy,放射增敏比值为1.32。下调NEK-2表达可提高因辐射诱导引起的凋亡水平(7.85%~17.17%),使细胞在Gz/M期阻滞(9.23%~30.16%),使DNA双链断裂的数M增加至165%,使DNA双链损伤的修复效率下降至48%。结论下调A549细胞中NEK-2表达水平能降低细胞的增殖能力,提高细胞放射敏感性,其作用机制可能与细胞周期变化、细胞凋亡以及DNA双链的断裂与修复有关。Objective To investigate the influence of down-regulation NEK-2 level on the radiosensitivity of A549 cells.Methods NEK-2 siRNA was transfected to A549 cells with liposome and NEK-2 expression level was inspected by W estern l)lot.The radiosensitivitv was detected by clone formation experiment.Cell cycle and cell apoptosis were analyzed by flow cytometry.Immunofluorescence experiment was used to detect the DNA double strand break and repair.Results NEK-2 siRNA successfully suppressed NEK-2 expression in A549 cells and resuced the cell proliferation ability after irradiation compared to the l)lank control group and the negative control group.It can improve the radiosensitivity of A549 cells(The radiosensitivity of A549 cells enhanced significantly.).The Do values declined form 1.80 Gy to 1.40 Gy,and the sensitizing enhancement ratio was 1.32.After irradiation,compared to negative control group,the apoptosis rate was significantly improved(7.85%to 17.17%),cells in G2/M phase were obviously increased(9.23%to 30.16%),the DNA double strand break rate was increased(100%to 165%)and the DNA damage repair rate was reduced(100%to 48%)in NEK-2 siRNA group.The comparisons among the groups wer statistically significant(P﹤0.05).Conclusions NEK-2 siRNA reduced the proliferation and increased the radiosensitivity of A549 cell line,probably by affecting the cell cycle,promoting cell apoptosis and suppressing DNA damage repair.

关 键 词：细胞增殖 凋亡 细胞周期 DNA修复 放射增敏 

分 类 号：R734.2[医药卫生—肿瘤]