放射抗拒食管癌细胞系的建立及抗拒机制研究

[目的]建立食管癌放射抗拒细胞系模型并观察食管癌细胞经射线反复照射后放射敏感性的变化。[方法]60Coγ射线对食管癌EC9706细胞系进行照射,每次2Gy,共照射30次,采用克隆形成实验等测定所得的EC9706R60细胞亚系及其亲代细胞EC9706的放射敏感性,检测细胞周期特征、细胞凋亡率及SP细胞(side population cells)比例。[结果]与亲代EC9706细胞相比,EC9706R60细胞显示出明显放射抗性,其D0、Dq及N值增大,细胞存活曲线肩区增宽,EC9706R60细胞的放射抗性(D0)是EC9706的1.375倍(P<0.05)。EC9706R60细胞S期比例较其EC9706细胞明显增高(32.1%vs.3.8%),G0/G1期比例则明显下降(67.9%vs.96.2%)。食管癌细胞EC9706在经30Gy照射后12h细胞凋亡达到峰值11.17%,经60Gy照射后降低到最低点0.99%。EC9706R60细胞SP细胞的比例较EC9706明显增高。[结论]EC9706R60细胞显示出与亲代细胞不同的细胞周期特征,放射抗拒性与SP细胞的比例存在一定关联。高的放射诱导凋亡率可能意味着放射越...

Establishment of Radioresistant Esophageal Cancer Cell Line and Its Radioresistance Mechanism

[Purpose] To establish a stable radioresistant esophageal cancer cell line model and to observe the variation of radiosensitivity with different dose of irradiation. [Methods] Human esophageal cancer cell line EC9706 was irradiated with 60Co γ-ray, 2Gy for 30 times. The radiosensitivity, cell cycle distribution, apoptosis rate and side population (SP) cells proportion of cloned cell subline EC9706R60, together with its parental EC9706 cells line were measured by clone formation assay, etc. [Results] Compari...