多功能纳米金在肺腺癌A549荷瘤小鼠模型中的放射增敏作用及Micro CT成像研究

Radiosensitization and micro CT imaging of multifunctional gold nanoparticles in lung adenocarcinoma A549 cell: an in vivo animal study

目的探究多功能纳米金在肺腺癌A549荷瘤小鼠模型中的放射增敏作用及Micro CT成像。方法荷瘤小鼠瘤体内注射纳米金,分别行160 kV X线及6 MV X线不同能量级照射,并测量肿瘤体积变化。瘤体内注射纳米金,在不同时间点行Micro CT扫描,观察纳米金在瘤组织中的成像及沉积时间。结果对照组与纳米金组肿瘤体积变化无明显差异(P=0.941)。6 MV X线联合纳米金组与6 MV X线组比较肿瘤体积略缩小,但两组没有统计学差异(P=0.730)。160 kV X线联合纳米金组肿瘤体积明显小于160 kV X线组(P=0.026)。Micro CT扫描显示纳米金在肿瘤中的沉积时间可持续30天,成像效果很好,且未见纳米金相关毒性。结论多功能纳米金对160 kV X线照射肺腺癌A549移植瘤有明显的放射增敏作用;纳米金瘤体的稳定CT成像可作为图像引导放疗肿瘤靶区定位和勾画的一种潜在方法。

Objective To evaluate the radiosensitization effect and micro CT imaging of multifunctional gold nanoparticles in lung adenocarcinoma A549 tumor-bearing mouse models. Methods The tumor-bearing mice were injected with gold nanoparticles and irradiated with different energy levels of 160 kV and 6 MV X-ray. The tumor volume changes were measured. Intra-tumoral injection of gold nanoparticles was administered and micro CT scan was performed at different time points to observe the imaging and retention time of gold nanoparticles in the tumor tissues. Results The tumor volume did not significantly differ between the control and gold nanoparticles groups (P=0.941). The tumor volume in the 6 MV X-ray combined with gold nanoparticles group was slightly reduced compared with that in the 6 MV X-ray group with no statistical significance (P=0.730). The tumor volume in the 160 kV X-ray combined with gold nanoparticles group was significantly smaller than that in the 160 kV X-ray group (P=0.026). Micro CT scan demonstrated that gold nanoparticles could be deposited in the tumors for 30 d and yielded excellent imaging effect. No gold nanoparticles-induced toxicity was observed. Conclusions Multifunctional gold nanoparticles exert significant radiosensitization effect in the lung adenocarcinoma A549 transplanted tumors irradiated with 160 kV X-ray. Stable CT imaging of the gold nanoparticles-injected tumors can be used as a potential method for mapping and delineating the target area in tumor-guided radiotherapy.