【摘要】 目的　通过辐射人喉鳞癌细胞株Hep- 2获得辐射耐受细胞株Hep- 2R ,建立一个放射敏感性研究的对比模型。方法　用γ线反复照射Hep- 2细胞,建立辐射耐受细胞Hep- 2R。成克隆实验法测定两株细胞不同剂量照射后的细胞存活分数,拟合细胞存活曲线比较两种细胞株的放射生物学参数。光镜、电镜、活细胞计数、染色体分析及流式细胞仪周期分布比较其生物学差异。结果　经7个月辐射诱导得到了一个放射敏感性不同于亲本细胞株的Hep -2R细胞株,并已稳定传30代以上且辐射耐受性能稳定。其SF2 =0 .6 80、D0 =3.2 4Gy、Dq=1.90Gy、N =1.80 ,而Hep 2细胞SF2 =0 .4 15、D0=2 .0 6Gy、Dq=1.0 1Gy、N =1.6 4。Hep -2R细胞形态及染色体数目发生了改变,群体倍增时间较亲本细胞延长。细胞周期分析显示G1期细胞增多,S、G2 期细胞减少。结论　通过辐射诱导可以从Hep -2细胞株得到辐射耐受细胞株Hep -2R ,这种相同背景、不同放射敏感细胞株为进一步研究放射敏感性的分子机制提供了一个良好对比模型。更多还原

【Abstract】 Objective Objective To establish a radioresistant tumor cell line and a radio sensitivity comparison model. Methods A radioresistant cell line, Hep-2R, was e stablished from a human larynx squamous carcinoma cell line Hep-2 by repeatedly irradiating for 7 months using γ-ray. Cell survival fraction was calculated b y colony forming assay, the radiobiology parameters of these two cell lines were compared by integrated cell survival curve. The biological difference between th ese two cell lines were determined by light microscopy, electronic microscopy, s urvival cell counting, flow cytometry(FCM) and chromosome analysis. Results Th e radioresistant cell line, Hep-2R, has already been maintained for more than 3 0 passages and has proved to be stable in passage culture as well as in frozen sa mples. The SF 2,D 0,D q,N were: 0.680,3.24,1.90,1.80 and 0.415,2.0 6,1.01,1 .64 for Hep-2 and Hep-2R cell line, respectively. The morphology and chromosom e number of Hep-2R changed; double time prolonged; and the cell number of G 1-p hase increased while those in S-phase and G 2-phase decreased when compared with it s parental cells. Conclusions Hep-2R cell line shows stable radioresistance. The comparison model between Hep-2R and Hep-2 is helpful for studying the molecula r mechanism of radiosensitivity.更多还原