Peng Yi-Yang, Hu Haimei, Diaz-Dussan Diana, Zhao Jianyang, Hao Xiaojuan, Narain Ravin
Department of Chemical & Materials Engineering, University of Alberta, Edmonton T6G 1H9, Alberta Canada.
The Commonwealth Scientific and Industrial Research Organization, Clayton, Victoria 3168, Australia.
ACS Macro Lett. 2022 Apr 19;11(4):580-587. doi: 10.1021/acsmacrolett.2c00046. Epub 2022 Apr 7.
Overexpression of epidermal growth factor receptor (EGFR) is observed in multiple cancers such as colorectal, lung, and cervical solid tumors. Regulating the EGFR expression is an efficient strategy to manage these malignancies, and it can be achieved by using short interfering RNA (siRNA). Cell-penetrating peptides (CPPs) demonstrated an excellent capability to enhance the cellular uptake of siRNA, but high knockdown efficiencies have not been achieved due to endosomal entrapment. In this work, Schiff's base reaction was used to modify a block {P[LAEMA(2-lactobionamidoethyl methacrylamide)]--P[FPMA(4-formyl phenyl methacrylate)--DMA(N,N-dimethylacrylamide)], } and two statistical [P(LAEMA--FPMA) () and P(LAEMA--FPMA--DMA) ()] aldehyde-based and galactose-based polymers, prepared via reversible addition-fragmentation chain-transfer (RAFT) polymerization. An arginine-rich peptide (ARP, KRRKRRRRRK) was used as a cell-penetrating peptide (CPP) and conjugated to the polymers via a Schiff base reaction. The resulting glycopolymer-peptide conjugates were utilized to condense the siRNA to prepare polyplexes with multivalent CPPs (MCPPs, a nanoparticle with multiple copies of the CPP) to enhance the endosomal escape. The polyplexes have different surface properties as determined by the architecture of polymers and the insertion of dimethyl amide moieties. The enhancement of cellular internalization of ARP was observed by labeling the polyplexes with fluorescein isothiocyanate (FITC)-siRNA showing a localization of polyplexes in the cytoplasm of a HeLa (cervical cancer) cell line. In the EFGR silencing study, the statistical glycopolymer-peptide (-P) polyplexes had superior EGFR silencing efficiency in comparison with the other polymers that were studied. Furthermore, -P polyplexes led to less off-targeting silencing than lipofectamine 3000. These encouraging results confirmed the potency of decorating galactose-based polymers with CPP, like ARP for their application in siRNA delivery and management of cervical carcinomas.
在多种癌症中，如结直肠癌、肺癌和宫颈癌实体瘤中，均观察到表皮生长因子受体（EGFR）的过表达。调控EGFR表达是治疗这些恶性肿瘤的有效策略，可通过使用小干扰RNA（siRNA）来实现。细胞穿透肽（CPP）展现出增强siRNA细胞摄取的出色能力，但由于内体截留，尚未实现高敲低效率。在这项工作中，利用席夫碱反应修饰了一种嵌段聚合物{P[LAEMA（2 - 乳糖酰胺基乙基甲基丙烯酸酯）] - - P[FPMA（4 - 甲酰基苯基甲基丙烯酸酯） - - DMA（N，N - 二甲基丙烯酰胺）]}以及两种统计共聚物[P（LAEMA - - FPMA）（）和P（LAEMA - - FPMA - - DMA）（）]，它们是通过可逆加成 - 断裂链转移（RAFT）聚合制备的基于醛和半乳糖的聚合物。一种富含精氨酸的肽（ARP，KRRKRRRRRK）用作细胞穿透肽（CPP），并通过席夫碱反应与聚合物共轭。所得的糖聚合物 - 肽共轭物用于凝聚siRNA，以制备具有多价CPPs（MCPPs，一种带有多个CPP拷贝的纳米颗粒）的多聚体，以增强内体逃逸。根据聚合物结构和二甲基酰胺部分的插入情况，多聚体具有不同的表面性质。通过用异硫氰酸荧光素（FITC） - siRNA标记多聚体，观察到ARP细胞内化的增强，显示多聚体在HeLa（宫颈癌）细胞系的细胞质中定位。在EGFR沉默研究中，统计糖聚合物 - 肽（ - P）多聚体与所研究的其他聚合物相比，具有更高的EGFR沉默效率。此外， - P多聚体导致的脱靶沉默比脂质体3000少。这些令人鼓舞的结果证实了用CPP修饰基于半乳糖的聚合物（如ARP）在siRNA递送和宫颈癌治疗中的潜力。
