中文摘要：

目的探讨单细胞凝胶电泳用于肿瘤细胞辐射敏感性检测的可行性。方法选取三种不同肿瘤细胞株：肝癌细胞（HepG2）、食管癌细胞（EC-9706）和乳腺癌细胞（MCF-7）。采用MTY法检测肿瘤细胞经γ射线照射后的存活分数（SF）；单细胞凝胶电泳（Single cell gel electrophoresis，SCGE）检测肿瘤细胞的DNA断裂水平。结果MTT法．2Gy、4Gy和SGy照射后，HepG2和EC-9706的SF显著低于MCF-7，表明HepG2和EC-9706细胞具有更高的辐射敏感性。SCGE：三种肿瘤细胞在8Gy照后表现出的辐射敏感性差别最显著。结论多种生物学指标的综合应用，有希望更加客观准确地评价肿瘤细胞的辐射敏感性。

英文摘要：

Objective ＇To explore the feasibility of determining radiosensitivity of human tumor cell lines in vitro using single cell gel electrophoresis（SCGE）. Methods Three human tumor cell lines were selected in this study, HepG2 ,EC -9706 and MCF -7. The surviving fraction（SF） and DNA damage were detected by MTT assay, nested PCR technique and comet assay respectively. Results MTT assay：The SF of HepG2 and EC -9706 after irradiated by 2,4and 8Gy was lower sig- nificantly than that of MCF - 7, which showed that the radiosensitivity of HepG2 and EC - 9706 was higher than that of MCF - 7. But there was no statistical difference of SF between HepG2 and EC - 9706. SCGE ： The difference of radiosensitivity among these three tumor cell lines was significant after 8Gy γ - ray irradiation. Conclusion The multi - utilization of many biological parameter is hopeful to evaluate the radiosensitivity of tumor cells more objectively and exactly.