中文摘要：

目的：筛选能提高鼻咽癌CNE-2细胞对β射线放射敏感性的CpGODN序列，观察筛选获得的CpGODN序列放射增敏的作用特点，为寻找新的鼻咽癌放疗增敏剂提供实验依据。方法：应用MTT实验筛选21种CpGODN序列中对人鼻咽癌CNE-2细胞放射增敏作用最强的序列，以MTT实验、集落形成实验、划痕实验和流式细胞术检测该最强作用序列与β射线联合作用对CNE-2细胞的增殖、集落形成、细胞迁移、细胞周期与凋亡的影响。结果：筛选实验显示CpGODN107对CNE-2细胞具有最高的增敏比（1．59±0．06），CpGODN107和β射线联合作用能以剂量依赖方式显著抑制CNE-2细胞的增殖，抑制效应显著高于单纯照射（P〈0．05，P〈0．01）；联合作用显著抑制CNE-2细胞集落形成和迁移能力，显著诱导细胞周期阻滞于G0／G1期，显著增加细胞凋亡（P〈0．01），上述作用效应均明显强于单纯B射线照射（P〈0．05或P〈0．01）。结论：CpGODN107可显著增强人鼻咽癌CNE-2细胞对β射线的照射敏感性，其放射增敏作用可能与诱导细胞周期阻滞和凋亡有关。

英文摘要：

Objective： To screen for specific CpG ODN sequence which can enhance the radiosensitivity of nasopharyngeal carcinoma cell line CNE-2 cells to β-ray and to observe the sensitivity-enhancing characters of the screened CpG ODN sequence, so as to provide evidence for searching novel sensitizer of nasopharyngeal carcinoma to radiation. Methods： MTT assay was used to select the strongest sequence to sensitize CNE-2 ceils to β-ray irradiation from 21 CpG ODN sequences. The effect of the selected sequence combined with β-ray irradiation were used to treat CNE-2 cells and the proliferation, colony forming, cell migration, cell cycle and apoptosis were all observed. Results： Screen assay found CpG ODN107 had the highest SER （1.59±0.06） for CNE-2 cells. CpG ODN107 combined with β-ray irradiation inhibited CNE-2 cell proliferation in a close - dependent manner, and the inhibitory effect was significantly higher than that of radiation alone （P 〈 0.05, P 〈 0.01 ）. CpG ODN107 combined with β-ray irradiation significantly inhibited the formation and migration of CNE-2 cell colony, and induced G0/G1 arrest and significantly increased cell apoptosis compared with that of radiation alone （P 〈 0.05 or 0.01 ）. Conclusion： Our results suggest that CpG ODN107 can greatly enhance the radiosensitivities of human nasopharyngeal carcinoma cell line CNE-2 to β-ray radiation, which might be related to the induction of cell cycle arrest and apoptosis.