新型纳米金材料的合成及其对HepG2细胞放射增敏的影响  

Synthesis of novel gold nanoparticles and its radiosensitizing effect on HepG2 cells

作　　者：王礼学[1] 王国相 丁建勋[3] 徐瀚峰[1] 童金龙[1] 郑勤[1] 

机构地区：[1]东南大学附属第二医院肿瘤科,南京210003 [2]南京至泰生物医药科技有限公司,南京210061 [3]中国科学院长春应用化学研究所中国科学院生态环境高分子材料重点实验室,长春130022

出　　处：《中华放射医学与防护杂志》2016年第12期881-887,共7页Chinese Journal of Radiological Medicine and Protection

基　　金：江苏省自然科学基金面上项目（BK20141084）

摘　　要：目的 合成新型纳米金复合物GAL-PEG-GNPs，探讨其体外放射增敏效应及增敏机制。方法 制备GAL-PEG-GNPs并进行表征。将HepG2细胞分为对照组、GNPs组和GAL-PEG-GNPs组。CCK-8法检测GAL-PEG-GNPs的细胞毒性，并计算IC50值；TEM和ICP-MS检测细胞对2种纳米材料的摄取；克隆形成实验检测放射增敏水平；流式细胞术分析细胞周期的变化；免疫蛋白印迹分析细胞凋亡相关蛋白变化；酶标仪检测细胞内过氧化氢酶（CAT）、超氧化物歧化酶（SOD）、总还原型谷胱甘肽（GSH）的表达水平。结果 GNPs和GAL-PEG-GNPs溶液的紫外可见吸收峰分别位于520和530 nm，GNPs和GAL-PEG-GNPs的直径分别为（22.6±2.12）和（32.0±1.41）nm。GAL-PEG-GNPs的细胞毒性与GNPs类似（P〉0.05），IC50值分别为5.001和4.997 μg/ml。GAL-PEG-GNPs被HepG2细胞的摄取量高于GNPs。GNPs和GAL-PEG-GNPs的放射增敏比（SER）分别为1.46和1.95。细胞经过处理后，处于G2/M期的比例明显提高（t=14.20，P〈0.05）。GNPs组和GAL-PEG-GNPs组Cytochrome C、Bax、Caspase-3、Caspase-9的表达水平较对照组明显提高，而Bcl-2的表达呈现降低趋势。GAL-PEG-GNPs组CAT、SOD、总GSH较对照组均明显减少（t=12.34、29.39、12.85，P〈0.05）。结论 GAL-PEG-GNPs对HepG2细胞具有较好的放射增敏效应，增敏机制可能与GNPs诱导大量自由基产生，进而启动凋亡基因程序有关。Objective To synthesize novel gold nanoparticles of GAL-PEG-GNPs, study its radiation effect on hepatocellular carcinoma cells HepG2 cells in vitro, and investigate the underlying mechanisms. Methods GAL-PEG-GNPs were synthesized and characterized successfully. HepG2 cells were divided into three groups of control, GNPs and GAL-PEG-GNPs. The cytotoxicities of these compounds were tested by the CCK-8 assay and their IC50 values of HepG2 cells were calculated. Cell uptake of nanoparticles was detected by TEM and ICP-MS. The radiosensitization effect of nanoparticles was tested by the colony formation assay. Cell cycle distribution was detected by FCM. The expressions of CAT, SOD, and total GSH were detected with a microplate reader, and the expressions of apoptosis-related proteins were tested by Western blot. Results The GNPs and GAL-PEG-GNPs had absorption peaks at 520 and 530 nm, respectively, and their diameters were （22.6±2.12） and （32.0±1.41） nm detected by ICP-MS. The GAL-PEG-GNPs and GNPs had similar cytotoxicity profiles （P〉0.05）, while GAL-PEG-GNPs could be more effectively uptaken by HepG2 cells than GNPs. The sensitive enhancement ratio （SER） of GNPs and GAL-PEG-GNPs to HepG2 cells were 1.46和1.95, respectively. The percentage of cells at phase of G2/M in HepG2 population treated with GNP was higher than that of untreated cells （t=14.20, P〈0.05）. The protein expressions of Cytochrome C, Bax, Caspase-3, and Caspase-9 were up-regulated while Bcl-2 expression was down-regulated in the cells treated with GNPs/radiation or GAL-PEG-GNPs/radiation. The expressions of CAT, SOD and total GSH in the GNP treated groups were significantly decreased compared with the control group（t=12.34, 29.39, 12.85, P〈0.05）. Conclusions GAL-PEG-GNPs has obvious radiosensitization effect on HepG2 cells, which is related to the induction of cell apoptosis and the generation of free radicals.

关 键 词：纳米金 半乳糖酸 Γ-H2AX 放射增敏 肝癌细胞 

分 类 号：R735.7[医药卫生—肿瘤]