Double Click-Functionalized siRNA Polyplexes for Gene Silencing in Epidermal Growth Factor Receptor-Positive Tumor Cells

Abstract

Sequence-defined lipo-oligomers generated via solid-phase assisted synthesis have been developed as siRNA delivery systems for RNA-interference (RNAi) based gene silencing. Here, novel siRNA lipo-polyplexes were established, which were postmodified with monovalent or bivalent DBCO-PEG24 agents terminated with peptide GE11 (YH­WYG­YTP­QN­VI) for epidermal growth factor receptor (EGFR)-targeted siRNA delivery into EGFR-positive tumor cells. Lipo-oligomers containing eight cationizable succinoyltetraethylene-pentamine (Stp) units mediated higher siRNA nanoparticle core stability than those containing four Stp units, and the incorporation of histidines for enhanced endosomal buffer capacity resulted in an improved gene silencing efficiency. Lipo-polyplexes modified with monovalent or bivalent PEG-GE11 via the copper-free click reaction possessed significantly enhanced cellular internalization and transfection efficiency in EGF receptor-positive human cervical KB and hepatoma Huh7 cells in comparison with the corresponding lipo-polyplexes shielded with PEG24 without targeting. Furthermore, modification with the bivalent DBCO-PEG24-GE11 ligand resulted in higher gene silencing efficiency than modification with the same equivalents of the monovalent DBCO-PEG24-GE11 ligand.

Transferrin Receptor Targeted Polyplexes Completely Comprised of Sequence‐Defined Components

“…All of them contain an N ‐terminal azidolysine, enabling postfunctionalization with DBCO agents via click chemistry as previously reported. [ 56–59 ]…”

Selective sodium iodide symporter (NIS) gene therapy of glioblastoma mediated by EGFR-targeted lipopolyplexes

“… 42 , 43 The peptide GE11 was selected for EGFR targeting based on its convincingly demonstrated capacity to provide EGFR-specific transfection efficiency in nanoparticle delivery both in vitro and in vivo in our previous studies. 8 , 28 , 29 , 30 , 31 , 44 , 45 , 46 , 47 , 48 In the present study, we monitored vector biodistribution and transfection efficiency by non-invasive imaging in an orthotopic GBM mouse model and subsequently demonstrated the potential therapeutic efficacy of our novel GE11-targeted NIS polyplexes after 131 I application.…”

“…The shielding and EGFR targeting agents, bearing one or two DBCO units as attachment sites for orthogonal click reaction, were synthesized as described previously. 45 , 47 …”

Smart Nanocarriers for the Delivery of Nucleic Acid‐Based Therapeutics: A Comprehensive Review

“…have developed a double‐click functionalized histidine‐bearing lipo‐oligomers for enhanced delivery of the epidermal growth factor receptor (EGFR)‐siRNA to target the EGFR‐positive cancer cells. [ 64 ] The presence of eight cationizable succinoyltetraethylene‐pentamine (Stp) units enhanced the nanoparticle stability, while histidine enhanced the gene silencing effect by augmenting the endosomal buffer capacity. [ 65 ] Higher gene silencing could be achieved by constructing multivalent siRNA conjugates by the conjugation of multiple siRNA to the poly(amino acids) [poly(lysine) derivatives].…”