Li Jun, Liu Jing, Li Shengnan, Hao Yanli, Chen Lei, Zhang Xiaoning
School of Medicine, Tsinghua University, Beijing 100084, China.
Collaborative Innovation Center for Biotherapy, Tsinghua University, Beijing 100084, China.
Oncotarget. 2016 Mar 22;7(12):13782-96. doi: 10.18632/oncotarget.7368.
The major obstacle to developing siRNA delivery is their extracellular and intracellular barriers. Herein, a humanized anti-EGFR monoclonal antibody h-R3 was developed to modify the self-assembled binary complexes (dendriplexes) of PAMAM and siRNA via electrostatic interactions, and two common ligands HSA and EGF were used as a control. Compared to dendriplexes, h-R3/EGF/HSA-dendriplexes showed increased particle size, decreased zeta potentials and lower cytotoxicity. Moreover, h-R3-dendriplexes presented greater cellular uptake and excellent endosomal escape ability in HepG2 cells. Ex vivo fluorescence imaging revealed that h-R3-dendriplexes showed higher targeted delivery and gene expression in the tumors than dendriplexes, HSA-dendriplexes and EGF-dendriplexes, which was in agreement with confocal results of cryosections. Furthermore, h-R3-dendriplexes for siPLK1 delivery indicated efficient gene silencing, potentiated cell growth inhibition and cell apoptosis, and suppressed cellular migration/invasion. These results indicate that h-R3-dendriplexes represent a great potential to be used as efficient targeted siRNA delivery carriers.
开发小干扰RNA（siRNA）递送的主要障碍是其细胞外和细胞内屏障。在此，开发了一种人源化抗表皮生长因子受体（EGFR）单克隆抗体h-R3，通过静电相互作用修饰聚酰胺-胺（PAMAM）与siRNA的自组装二元复合物（树枝状复合物），并使用两种常见配体人血清白蛋白（HSA）和表皮生长因子（EGF）作为对照。与树枝状复合物相比，h-R3/EGF/HSA-树枝状复合物粒径增大、zeta电位降低且细胞毒性更低。此外，h-R3-树枝状复合物在肝癌细胞系（HepG2）中表现出更高的细胞摄取率和出色的内体逃逸能力。体外荧光成像显示，h-R3-树枝状复合物在肿瘤中的靶向递送和基因表达高于树枝状复合物、HSA-树枝状复合物和EGF-树枝状复合物，这与冷冻切片的共聚焦结果一致。此外，用于递送针对纺锤体和着丝粒相关蛋白1（siPLK1）的h-R3-树枝状复合物显示出有效的基因沉默、增强的细胞生长抑制和细胞凋亡，并抑制细胞迁移/侵袭。这些结果表明，h-R3-树枝状复合物作为高效的靶向siRNA递送载体具有巨大潜力。
