慢病毒载体介导的靶向沉默xrcc3基因对鼻咽癌细胞放疗增敏作用的影响

摘要

Objective To investigate the effect of xrcc3 on nasopharyngeal carcinoma cells radiosensitivity.Methods Colony formation assay was used to calculate the survival fraction under different radiation dose, and the sensitization enhancement ratio(SER) was also calculated.Cell apoptosis was examined by flow cytometry and Western blot was used to detect apoptosis proteins.DNA damage was determined by immunofluorescence.Results The results indicated that nasopharyngeal carcinoma CNE2 cells deficient in xrcc3 exhibited increased clonogenic survival in response to ionizing radiation(IR) compared with control cells, and the SER=1.232 3.Silence of xrcc3 in CNE2 cells increased radiation-induced DNA damage and apoptosis.Conclusion The fingdings show that xrcc3 may increase nasopharyngeal carcinoma cells radiation sensitivity by decreasing radiation-induced DNA damage and apoptosis.Therefore, xrcc3 might be a promising therapeutic gene for nasopharyngeal carcinoma.%目的 探讨X射线修复交叉互补蛋白3(XRCC3)对鼻咽癌细胞放疗敏感性的影响.方法 利用平板克隆实验检测不同放疗剂量下鼻咽癌细胞CNE2的存活分数,并计算放疗增敏比(SER);流式细胞仪通过Annexin V/PI双染检测细胞凋亡,并用Western blot检测凋亡蛋白的表达水平;在免疫荧光染色下观察放疗前后DNA的损伤.结果 沉默xrcc3基因能够降低CNE2细胞放疗后的存活分数,SER=1.232 3;提高射线引起的细胞凋亡,并增加细胞凋亡蛋白断裂带的产生;增加射线诱导的DNA双链损伤修复聚焦点的形成.结论 XRCC3可以通过降低鼻咽癌细胞放疗后DNA的损伤及细胞凋亡,从而增加鼻咽鳞癌细胞对放疗的抵抗,xrcc3可能作为一个提高鼻咽癌放疗敏感性的靶向基因.