摘要
目的探讨由核酸适配体介导的新型靶向铁磁纳米颗粒增强上皮细胞黏附分子（EpCAM）阳性肿瘤细胞热疗效应的作用。方法利用生物素与链霉亲和素的亲合作用将EpCAM核酸适配体SYL3C与铁磁纳米颗粒连接构建核酸适配体一铁纳米粒复合物（AptNPs），应用动态光散射粒径仪评估其直径大小，普鲁士蓝染色观察AptNPs对EpCAM阳性肿瘤细胞的靶向结合特性，乳酸脱氢酶检测AptNPs在交变电磁场作用下对EpCAM阳性肿瘤细胞的热杀伤效应，吖啶橙／溴化乙锭双染观察其引起EpCAM阳性肿瘤细胞的凋亡情况。结果生物素一链霉亲和素将SYL3C与铁磁纳米颗粒连接成功构建AptNPs，AptNPs直径为282nm。流式细胞仪检测和普鲁士蓝染色显示，AptNPs对EpCAM阳性肿瘤细胞有较强的选择结合特异性，对EpCAM阴性肿瘤细胞结合较弱。在交变电磁场加热5h后，1．5×10^8个AptNPs使EpCAM阳性细胞HCTll6存活率仅为28．9％，A549细胞为54．4％，与EpCAM阴性细胞HepG2细胞（76．7％）比较，差异均有统计学意义（均P〈0．05）。结论AptNPs可以靶向性地提高对EpCAM阳性肿瘤细胞热疗的效应，在肿瘤靶向治疗新策略中具有潜在的应用价值。
Objective To explore the thermal damage to epithelial cell adhesion molecule （EpCAM）-positive tumor cells by novel aptamer-guided magnetic nanoparticles（AptNPs）. Methods EpCAM aptamer SYL3C was connected to NPs via biotin-streptavidin reaction. The diameter of AptNPs were characterized by Dynamic Light Scattering （DLS）. The binding feature of the aptamer to EpCAM-positive tumor ceils was evaluated by Prussian blue dyeing. Thermal damage under alternative magnetic field was measured bylactate dehydrogenase （LDH）. The apoptosis of EpCAM-positive tumor cells was detected by acridine orange/ethidium bromide （AO/EB） double staining. Results The average size of AptNPs was 282 nm. Flow cytometry and Prussian blue dyeing showed that AptNPs exhibited strong binding to the EpCAM- positive tumor cells hut not to the EpCAM-negative tumor cells. Moreover, when incubated with 1.5×10^8 AptNPs under alternative electromagnetic fieldfor 5 hours, the viability of EpCAM-positive HCTll6 cells and A549 cells was 28.9% and 54.4%, respectively, significantly lower than 76.7% of EpCAM-negative HepG2 cells （P〈0.05）. Conclusions AptNPs can improve the thermal damage to EpCAM-positive tumor cells, and may have potential utility in the development of tumor targeted therapy.
出处
《中华肿瘤杂志》
CAS
CSCD
北大核心
2017年第10期726-731,共6页
Chinese Journal of Oncology
基金
西安市科技计划项目[SFl510（4）]
