【摘要】 目的探讨环氧化酶-2选择性抑制药NS398对放射抗拒食管癌细胞的放疗增敏效应。方法通过γ射线反复照射EC9706细胞,每次照射剂量200cGy,再克隆培养,重复以上过程达到累计放射剂量6000cGy,筛选得到放射抗拒细胞株EC9706R,采用克隆形成实验检测EC9706R及其亲本细胞的放射敏感性。采用不同浓度的NS398处理EC9706R细胞,研究它对EC9706R细胞放射敏感性的影响。结果筛选得到的放射抗拒人食管鳞癌细胞株EC9706R较亲本细胞显示出明显的放射抗性,不同浓度的NS398对食管癌EC9706R细胞均具有放疗增敏效应,25,50,100,150μmol.L-1的NS398作用24h后均能检测到放疗增敏作用,其放射增敏比SERSF2、SERDq分别为1.05,1.10,1.15,1.23和1.14,1.28,1.36,1.67,呈剂量依赖关系。结论NS398对放射抗拒食管癌细胞EC9706R具有明显的放疗增敏作用。更多还原

【Abstract】 Objective To investigate the effect of radiosensitization of NS398（selective cyclooxygene-2 inhibitor） on radioresistant esophageal carcinoma cells. Methods A radioresistant cell line,EC9706R,was established from a human esophageal cancer cell line EC9706 by repeatedly irradiating using gamma rays with each dose exposure 200 cGy,and repeatedly cloning training until total dose exposures 6 000 cGy.The tumor radiosensitivity of EC9706R and its pro-cells were measured by clone forming assay.EC9706R was processed with NS398 of different concentrations,so as to study its influence on the radiosensitivity of EC9706R. Results A radioresistant esophageal cancer cell line EC9706R was successfully established.EC9706R cells showed more obvious radiation resistance than their pro-cells.NS398 of 25,50,100 and 150 μmol·L^-1 all had radiosensitizing effect on EC9706R cells.The sensitization enhancement ratios of SF2,Dq in EC9706R cells were 1.05,1.10,（1.15）,1.23 and 1.14,1.28,1.36,1.67,respectively,which showed a dose-dependant relationship. Conclusion It is suggested that selective COX-2 inhibitor obviously enhance the radiosentivity of human esophageal carcinoma cell line EC9706R.更多还原