Dataset Information

Rationally Designed Polycationic Carriers for Potent Polymeric siRNA-Mediated Gene Silencing.

ABSTRACT: The delivery of small interfering RNA (siRNA) remains a major hurdle for the clinical translation of RNA interference (RNAi) therapeutics. Because of its low valency and rigid nature, siRNA typically requires high excesses of cationic delivery materials to package it stably and deliver it to the cytoplasm of target cells, resulting in high toxicities and inefficient gene silencing in vivo. To address these challenges, we pair a polymeric form of siRNA, p-shRNA, with optimized biodegradable polycations to form stable complexes that induce far more potent gene silencing than with siRNA complexes. Furthermore, we unveil a set of design rules governing p-shRNA delivery, using degradable polycations containing hydrophobic and stabilizing polyethylene glycol domains that enable both stable condensation and efficient release inside cells. We demonstrate the therapeutic potential of this approach by silencing the oncogene STAT3 in a well-established B16F10 mouse melanoma model to significantly prolong survival. By blending nucleic acid engineering and polymer design, our system provides a potentially translatable platform for RNAi-based therapies.

SUBMITTER: Wu C

PROVIDER: S-EPMC6152829 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Rationally Designed Polycationic Carriers for Potent Polymeric siRNA-Mediated Gene Silencing.

Wu Connie C Li Jiahe J Wang Wade W Hammond Paula T PT

ACS nano 20180628 7

The delivery of small interfering RNA (siRNA) remains a major hurdle for the clinical translation of RNA interference (RNAi) therapeutics. Because of its low valency and rigid nature, siRNA typically requires high excesses of cationic delivery materials to package it stably and deliver it to the cytoplasm of target cells, resulting in high toxicities and inefficient gene silencing in vivo. To address these challenges, we pair a polymeric form of siRNA, p-shRNA, with optimized biodegradable polyc ...[more]

PMID: 29944833

Similar Datasets

Project description:The ability of small interfering RNA (siRNA) to efficiently silence the expression of specific genes provides the basis for exciting new therapies based on RNA interference (RNAi). The efficient intracellular delivery of siRNA from cell uptake through the endosomal trafficking pathways into the cytoplasm remains a significant challenge. Previously we described the synthesis of a new family of diblock copolymer siRNA carriers using controlled reversible addition-fragmentation chain transfer (RAFT) polymerization. The carriers were composed of a positively charged block of dimethylaminoethyl methacrylate (DMAEMA) to mediate siRNA binding and a second pH-responsive endosome releasing block composed of DMAEMA and propylacrylic acid (PAA) in roughly equimolar ratios and butyl methacylate (BMA). Here we describe the development of a new generation of siRNA delivery polymers based on this design that exhibit enhanced transfection efficiency and low cytotoxicity. This design incorporates a longer endosomolytic block with increased hydrophobic content to induce micelle formation. These polymers spontaneously form spherical micelles in the size range of 40 nm with CMC (critical micelle concentration) values of approximately 2 μg/mL based on dynamic light scattering (DLS), (1)H NMR, electron microscopy, and selective partitioning of the small molecule pyrene into the hydrophobic micelle core. The siRNA binding to the cationic shell block did not perturb micelle stability or significantly increase particle size. The self-assembly of the diblock copolymers into particles was shown to provide a significant enhancement in mRNA knockdown at siRNA concentrations as low as 12.5 nM. Under these conditions, the micelle-based systems showed an 89% reduction in GAPDH mRNA levels as compared to only 23% (10 nM siRNA) for the nonmicelle system. The reduction in mRNA levels becomes nearly quantitative as the siRNA concentration is increased to 25 nM and higher. Flow cytometry analysis of fluorescent-labeled siRNA showed uptake in 90% of cells and a 3-fold increase in siRNA per cell compared to a standard lipid transfection agent. These results demonstrate the potential utility of this carrier design for siRNA drug delivery.

Dataset Information

Rationally Designed Polycationic Carriers for Potent Polymeric siRNA-Mediated Gene Silencing.

Publications

Rationally Designed Polycationic Carriers for Potent Polymeric siRNA-Mediated Gene Silencing.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets