CAJ | 학술논문

目的探讨肺腺癌细胞株表皮生长因子受体(EGFR)酪氨酸激酶区域突变对放射线诱导的DNA双链断裂后修复的影响.方法对A549细胞株(wt EGFR)和H1975细胞株(mutEGFR)进行6MVX射线照射.免疫荧光方法观察两种细胞株经4 GyX射线照射后不同时间点细胞核中γH2AX焦点数.免疫共沉淀法检测EGFR与DNA-PKcs的结合情况.Western blot方法检测细胞核中RAD51表达以及EGFR核转运情况.结果 H1975细胞株(mutEGFR)经X射线照射后DNA双链断裂修复延缓,EGFR不进行核转运,细胞核中无EGFR-DNA-PKcs复合物形成,且不影响细胞核RAD51的表达.A549细胞株(wt EGFR)经射线诱导后EGFR发生核转运,并与DNA-PKcs结合,发挥非同源修复,同时RAD51进入细胞核,发挥同源修复作用.结论 EGFR酪氨酸激酶区突变的肺腺癌细胞株能减少X射线诱导的DNA双链断裂后非同源修复和同源修复,延缓DNA修复动力学,从而增加放射敏感性.
목적 탐토폐선암세포주표피생장인자수체(EGFR)락안산격매구역돌변대방사선유도적DNA쌍련단렬후수복적영향.방법 대A549세포주(wt EGFR)화H1975세포주(mutEGFR)진행6MVX사선조사.면역형광방법관찰량충세포주경4 GyX사선조사후불동시간점세포핵중γH2AX초점수.면역공침정법검측EGFR여DNA-PKcs적결합정황.Western blot방법검측세포핵중RAD51표체이급EGFR핵전운정황.결과 H1975세포주(mutEGFR)경X사선조사후DNA쌍련단렬수복연완,EGFR불진행핵전운,세포핵중무EGFR-DNA-PKcs복합물형성,차불영향세포핵RAD51적표체.A549세포주(wt EGFR)경사선유도후EGFR발생핵전운,병여DNA-PKcs결합,발휘비동원수복,동시RAD51진입세포핵,발휘동원수복작용.결론 EGFR락안산격매구돌변적폐선암세포주능감소X사선유도적DNA쌍련단렬후비동원수복화동원수복,연완DNA수복동역학,종이증가방사민감성.
Objective To observe the effect of EGFR mutation on radiation induced DNA repair in pulmonary adenocarcinoma ceils.Methods A549 cells with wild-type EGFR and H1975 cells with mutated-type of EGFR were irradiated by 4 Gy of 6 MV X-rays.After irradiation,the formation of nuclear γ-H2AX foci was assayed with immunostaining method,the level of DNA-PKcs-EGFR interaction was detected with coimmunoprecipitation,and nuclear RAD51 expression and EGFR nuclear translocation were detected using Western blot.Results DNA repair in the H1975 cells was significantly lower than that in A549 cells.In the irradiated H1975 cells,there was no EGFR translocation with further nuclear DNA-PKcs binding,and the expression of nucleus RAD51 was not altered.But in the irradiated A549 cells,EGFRDNA-PKcs interaction and nucleus RAD51 were increased.Conclusions Lung adenocarcinoma cell line with mutations in the tyrosine kinase domain (TKD) of EGFR exhibits a high radiosensitivity due to the reduction of the non-homologous end-joining (NHEJ) and homologous recombination (HR) DNA DSB repair kinetics.