IMRT、VMAT模式照射离体人肺癌细胞的生物学效应研究  

Study on the biological effects of IMRT and VMAT irradiation for the human lung cancer cells in vitro

作　　者：董俊林[1] 赵静[2] 朱定清[1] 王思阳[3] 龚五星[1] 李小亮[1] 张振林[1] 

机构地区：[1]广东省珠海市人民医院,广东珠海519000 [2]澳门大学,澳门999078 [3]中山大学第五附属医院,广东珠海519000

出　　处：《中国医药导报》2016年第24期36-39,共4页China Medical Herald

基　　金：广东省珠海市科技计划项目(2014130)

摘　　要：目的观察调强适形放射治疗(IMRT)、容积旋转调强放射治疗(VMAT)模式照射离体人肺癌细胞的生物效应,研究IMRT、VMAT模式放疗照射的作用机制,为制订合理的临床放疗方案提供理论依据。方法选取人肺鳞癌细胞SK-MES-1、人肺小细胞癌细胞NCI-H446,分别进行体外琼脂悬浮克隆培养法建立肿瘤模型。分别使用9个不同的照射剂量点进行急速照射研究,照射3 min后计算细胞存活分数,采用Graph Pad Prism软件处理数据,根据线性二次方程拟合细胞存活曲线,再把呈指数生长期的SK-MES-1、NCI-H446分别分成四个组:1VMAT模式照射组(直线型加速器能量为6 MV 6 min照射);IMRT模式15 min照射组;IMRT模式30 min照射组;IMRT模式45 min照射组。每组照射总量为8 Gy,1次/d,2 Gy/次,4 d内完成。最后,采用克隆分析法计算细胞的存活分数,对比IMRT模式和VMAT模式的放射特点及生物效应。结果①急速照射完成后,分析得到SK-MES-1、NCI-H446细胞的放射生物学参数。SK-MES-1细胞各参数详细数值分别为(D_0、Dq、N值、α值、β值、α/β值):0.87 Gy、0.48 Gy、3.6、0.17 Gy^(-1)、0.091 Gy^(-2)、1.87 Gy;NCI-H446细胞以上各参数数值分别为0.61 Gy、0.35 Gy、4.0、0.98 Gy^(-1)、0.089 Gy^(-2)、11.01 Gy。②总量为8 Gy的4 d照射中,SK-MES-1细胞各照射组(VMAT模式照射组和IMRT模式15、30、45 min照射组)的细胞存活率分别为7.25%、8.95%、9.63%、11.32%,IMRT模式照射下的细胞存活率较VMAT模式明显增加。NCI-H446细胞以上各组照射后的细胞存活率分别为0.192%、0.205%、0.208%、0.209%,差异不明显。结论人肺鳞癌细胞SK-MES-1的细胞放射敏感性(D_0、N值)相对人肺小细胞癌细胞NCI-H446更低,亚致死性损伤修复能力(Dq值和α/β值)相对NCI-H446细胞更强,剂量率改变对其放射生物效应影响明显,IMRT模式单次剂量输出时间延长导致SK-MES-1细胞生存率增加,NCI-H446细胞增加不明显。Objective To observe the biological effects of intensity-modulated radiotherapy （IMRT） and volumetric modulated arc therapy （VMAT） irradiation for the human lung cancer Cells in vitro, and to study the mechanism of IMRT and VMAT irradiation, in order to provide evidence for formulating reasonable Clinical radiotherapy plan. Methods The human lung squamous carcinoma cells SK-MES-1 and human lung small cell~ cancer cells NCI-H446 were selected to establish tumor model by agar suspension culture method in vitro, then the cells were given rapid radiation research at 9 dose levels. After irradiation for 3 min,＇the survival percentage of cells was calculated, GraphPad Prism software was used to process data, the cell survival curve was fit with linear-quadratic formula, then the SK-MES-i, NCI-H446 at exponential growth phase were divided into four groups： VMAT irradiation group （the energy of linear accelerator was 6 MV, for 6 min）; IMRT irradiation for 15 min group; IMRT irradiation for 30 rain group; IMRT irradiation for 45 min group. The total irradiation of each group was 8 Gy, once a day, 2 Gy every time, finished in 4 days. At last, the cloning assay was used to calculate the survival rate of cells, to compare the radiation characteristics and biological effects between IMRT model and VMAT model. Results （1）After finishing rapid radiation, the radiobiological parameters of SK-MES-1, NCI-H446 cells were achieved. The detailed numerical value of each parameter of SK-MES-1 cells （DO, Dq, N value, α value, β value, α/β value） was 0.87 Gy, 0.48 Gy, 3.6, 0.17 Gy-l, 0.091 Gy-2, 1.87 Gy respectively; which of NCl-H446 cells was 0.61 Gy, 0.35 Gy, 4.0, 0.98 Gy-1, 0.089 Gy-2, 11.01 Gy respectively. （2）In the irradiation of 4 d with 8 Gy, the survival rate of SK-MES-1 ceils in au groups （VMAT irradiation group and IMRT irradiation for 15, 30, 45 min group） was 7.25%, 8.95%, 9.63%, 11.32% respectively, the survival rate under the IMRT irradiation was higher than that of VMAT irradiation. Th

关 键 词：人肺癌细胞 调强适形放射治疗 容积旋转调强放射治疗 生物效应 

分 类 号：R734.2[医药卫生—肿瘤]