Ayatollahi Sara, Salmasi Zahra, Hashemi Maryam, Askarian Saeedeh, Oskuee Reza Kazemi, Abnous Khalil, Ramezani Mohammad
Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Nanotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Int J Biochem Cell Biol. 2017 Nov;92:210-217. doi: 10.1016/j.biocel.2017.10.005. Epub 2017 Oct 12.
RNAi-based gene therapy has been recently considered as a promising approach against cancer. Targeted delivery of drug, gene or therapeutic RNAi-based systems to tumor cells is one of the important issues in order to reduce side effects on normal cells. Several strategies have been developed to improve the safety and selectivity of cancer treatments including antibodies, peptides and recently aptamers with various attractive characteristics including higher target specificity, affinity and reduced toxicity. Here we described a novel targeted delivery platform comprising modified PAMAM with 10-bromodecanoic acid (10C) and 10C-PEG for improvement of transfection efficiency, AS1411 aptamer for targeting nucleolin ligand on target cancer cells and shRNA plasmid for specific knockdown of Bcl-xL protein. Modified vector could significantly improve the transfection efficiency even after covalent or non-covalent aptamer binding compared to the non-targeted vector in A549 cells. The results of gene silencing and apoptosis assay indicated that our targeted shRNA delivery system could efficiently down-regulate the Bcl-xL expression up to 25% and induce 14% late apoptosis in target cancer cells with strong cell selectivity. This study proposed a novel targeted non-viral system for shRNA-mediated gene-silencing in cancer cells.
基于RNA干扰的基因疗法最近被认为是一种有前景的抗癌方法。将药物、基因或基于RNA干扰的治疗系统靶向递送至肿瘤细胞是减少对正常细胞副作用的重要问题之一。已经开发了几种策略来提高癌症治疗的安全性和选择性，包括抗体、肽以及最近具有各种吸引人特性（如更高的靶标特异性、亲和力和更低毒性）的适体。在此，我们描述了一种新型的靶向递送平台，其包含用10-溴代癸酸（10C）和10C-聚乙二醇修饰的聚酰胺-胺型树枝状大分子（PAMAM）以提高转染效率，用于靶向靶癌细胞上核仁素配体的AS1411适体，以及用于特异性敲低Bcl-xL蛋白的短发夹RNA（shRNA）质粒。与A549细胞中的非靶向载体相比，即使在共价或非共价适体结合后，修饰载体仍能显著提高转染效率。基因沉默和凋亡检测结果表明，我们的靶向shRNA递送系统能够有效地将靶癌细胞中的Bcl-xL表达下调高达25%，并诱导14%的晚期凋亡，具有很强的细胞选择性。本研究提出了一种新型的靶向非病毒系统，用于在癌细胞中进行shRNA介导的基因沉默。
