碘-125粒子照射对骨组织影响的细胞生物学及放射物理学研究

项目名称： 碘-125粒子照射对骨组织影响的细胞生物学及放射物理学研究

项目编号： No.81502652

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 黄明伟

作者单位： 北京大学

项目金额： 18万元

中文摘要： 减少对骨组织的毒副反应是放射治疗头颈肿瘤关注的一项重要内容和难点。临床应用125I粒子治疗头颈肿瘤取得较好疗效，且放射性骨损伤少。本研究拟揭示125I粒子照射对成骨细胞增殖和分化的影响，并从放射物理学上评价计算骨组织对125I粒子剂量分布的影响，为125I粒子在头颈部的应用提供理论依据。利用125I粒子和60Co外照射分别对成骨细胞进行等剂量照射，检测其对细胞凋亡和增殖的影响；RT-PCR及Western-blot检查骨分化相关基因的表达，并检测Runx2相关TGF/β1和IGF-1信号通路关键因子的基因和蛋白表达，拟揭示成骨细胞增殖和分化能力变化，并探讨相关机制。利用蒙特卡罗运算，构建125I粒子照射骨组织的模型，并利用人工材料实际测量，在国际上首次得出骨组织对125I射线的半价层厚度；并模拟头颈部125I粒子治疗过程中骨组织接受的剂量分布及其对靶区粒子剂量分布的影响，指导临床合理布源。

中文关键词： 成骨细胞；蒙特卡罗；剂量分布；细胞增殖；细胞分化

英文摘要： It is an important and difficult problem to reduce the radiation toxicity to bone tissue associated with radiation therapy of head and neck tumors. 125I brachytherapy of head and neck tumors achieved good effect with less radiation complications to bone tissues. This study will reveal the influence of 125I radiation on osteoblast proliferation and differentiation, and to evaluate the influence of bone tissues on 125I dose distribution, which will provide a theoretical basis for the application of 125I brachytherapy on the head and neck tumors. Using 125I seeds and 60Co external radiation irradiated the osteoblasts with different doses, and then detecting the influence of radiation on apoptosis and proliferation.Then RT-PCR and Western-blot technique will be used to examine bone differentiation-related genes and Runx2 related TGF/β1 and IGF-1 signal pathways key factors, which will reveal the changes of bone cell proliferation and differentiation and explore the mechanism. Using Monte Carlo calculation builds models of 125I brachytherapy on bone tissues, and the dose distribution in artificial materials will be measured. The 125I-ray bone tissue half thickness will be calculated the first time in the world. The bone dose distribution of 125I brachytherapy and the impact of bone on the dose distribution of the soft tissue target area in head and neck will be simulated, which will guide clinical rational seeds distribution.

英文关键词： Osteoblasts;Monte Carlo;Dose distribution;Cell proliferation;Cell differentiation