放射耐受性人小细胞肺癌亚株的建立

The establishment of a radiation-resistant small cell lung cancer subline

目的建立肺癌NCI-H446细胞放射抗拒性亚株,为小细胞肺癌放射抗拒和逆转研究提供配对的细胞研究工具。方法通过梯度照射NCI-H446细胞株诱导其耐放射性(共7500c Gy),并通过检测细胞总的ATP含量的方法来监测细胞倍增时间,流式细胞仪检测细胞周期分布,以及应用多靶单击模型SF=1-(1-e-D/D0)N拟合细胞存活曲线分析其放射敏感参数的变化。结果比较亲本与耐放射株的差异,放射生物学参数值分别为D0(1.9673,2.2756)、N(1.0016,2.6008)、Dq(0.6783,1.6860)、SF2(0.3623,0.7134),耐放射株SF2值为亲本的1.97倍,G2/M期细胞所占比由18.52%下降到7.84%。耐放射株的细胞形态发生变化,倍增时间比敏感株延长。结论通过梯度照射建立了小细胞肺癌NCI-H446的耐放射亚株NCI-H446-R,与亲本细胞相比放射生物学参数有显著差异(P<0.05),本研究成果为研究小细胞肺癌放射抗拒及耐放射逆转提供了新的细胞模型。

Objective To establish a radiation-resistant cell subline from a human small cell lung cancer（ SCLC）cell line NCI-H446,providing a pairing research tool for investigating mechanism of radiation tolerance and the reverse strategy in lung cancer. Methods The NCI-H446 cell was radiated repeatedly by increased dose of radiation gradually（ total 7500 c Gy） and a radiation-resistant cell substrain was induced and selected from the survival of cells. The doubling time and cell cycle distribution of the substrain were detected by ATP kit and flow cytometry Assay respectively; Radiation biology parameters were calculated and analyzed by cell survival curve fitting from multi-target model,SF = 1-（ 1- e-D /D0） N. Results Comparing with the control,The resistant substrain radiobiology parameter values were D0（ 1. 9673,2. 2756）,N（ 1. 0016,2. 6008）,Dq（ 0. 6783,1. 6860） and SF2（ 0. 3623,0. 7134） respectively. Cell morphology is more slender and has more tentacles. The SF2 value of radiation-resistant subline is 1. 97 times more than that of wild cell line.The proportion of radiation-resistant cells in G2 / M-phase was down to 7. 84%,compared with the 18. 52% of wild cells.Conclusions A radiation-resistant SCLC subline NCI-H446-R is established and may be a useful tool for studying resistant to radiation of SCLC in the future.