Li Lin, Hu Xiaoqin, Zhang Min, Ma Siyu, Yu Fanglin, Zhao Shiqing, Liu Nan, Wang Zhiyuan, Wang Yu, Guan Hua, Pan Xiujie, Gao Yue, Zhang Yue, Liu Yan, Yang Yang, Tang Xuemei, Li Mingyuan, Liu Cheng, Li Zhiping, Mei Xingguo
State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China.
Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China.
Mol Ther Nucleic Acids. 2017 Sep 15;8:169-183. doi: 10.1016/j.omtn.2017.06.014. Epub 2017 Jun 21.
Highly specific and efficient delivery of siRNA is still unsatisfactory. Herein, a dual tumor-targeting siRNA delivery system combining pRNA dimers with chitosan nanoparticles (CNPPs) was designed to improve the specificity and efficiency of siRNA delivery. In this dual delivery system, folate-conjugated and PEGylated chitosan nanoparticles encapsulating pRNA dimers were used as the first class of delivery system and would selectively deliver intact pRNA dimers near or into target cells. pRNA dimers simultaneously carrying siRNA and targeting aptamer, the second class of delivery system, would specifically deliver siRNA into the target cells via aptamer-mediated endocytosis or proper particle size. To certify the delivering efficiency of this dual system, CNPPs, pRNA dimers alone, chitosan nanoparticles containing siRNA with folate conjugation and PEGylation (CNPS), and chitosan nanoparticles containing pRNA dimers alone (CN) were first prepared. Then, we observed that treatment with CNPPs resulted in increased cellular uptake, higher cell apoptosis, stronger cell cytotoxicity, and more efficacious gene silencing compared to the other three formulations. Higher accumulation of siRNA in the tumor site, stronger tumor inhibition, and longer circulating time were also observed with CNPPs compared to other formulations. In conclusion, this dual nanocarrier system showed high targeting and favorable therapeutic efficacy both in vitro and in vivo. Thereby, a new approach is provided in this study for specific and efficient delivery of siRNA, which lays a foundation for the development of pRNA hexamers, which can simultaneously carry six different substances.
小干扰RNA（siRNA）的高度特异性和高效递送仍不尽人意。在此，设计了一种将pRNA二聚体与壳聚糖纳米颗粒（CNPPs）相结合的双肿瘤靶向siRNA递送系统，以提高siRNA递送的特异性和效率。在这个双递送系统中，包裹pRNA二聚体的叶酸偶联和聚乙二醇化壳聚糖纳米颗粒被用作第一类递送系统，它将选择性地将完整的pRNA二聚体递送至靶细胞附近或进入靶细胞。作为第二类递送系统的同时携带siRNA和靶向适体的pRNA二聚体，将通过适体介导的内吞作用或合适的粒径将siRNA特异性递送至靶细胞。为了验证这个双系统的递送效率，首先制备了CNPPs、单独的pRNA二聚体、含有叶酸偶联和聚乙二醇化siRNA的壳聚糖纳米颗粒（CNPS）以及仅含有pRNA二聚体的壳聚糖纳米颗粒（CN）。然后，我们观察到与其他三种制剂相比，用CNPPs处理导致细胞摄取增加、更高的细胞凋亡、更强的细胞毒性以及更有效的基因沉默。与其他制剂相比，用CNPPs还观察到siRNA在肿瘤部位的积累更高、更强的肿瘤抑制作用以及更长的循环时间。总之，这种双纳米载体系统在体外和体内均显示出高靶向性和良好的治疗效果。因此，本研究为siRNA的特异性和高效递送提供了一种新方法，为可同时携带六种不同物质的pRNA六聚体的开发奠定了基础。
