Double Controlled Release of Therapeutic RNA Modules through Injectable DNA–RNA Hybrid Hydrogel

Abstract

Advances in the DNA nanotechnology have enabled the fabrication of DNA-based hydrogels with precisely controlled structures and tunable mechanical and biological properties. Compared to DNA hydrogel, preparation of RNA-based hydrogel remains challenging due to the inherent instability of naked RNA. To overcome these limitations, we fabricated a DNA−RNA hybrid hydrogel via stepwise dual enzymatic polymerization. Multimeric short hairpin RNAs (shRNAs) were hybridized with functional DNA aptamers for targeting and mechanical properties of the hydrogel. The obtained DNA−RNA hybrid hydrogel was ultrasoft, robust, and injectable hence reconfigurable into any confined structures. As a model system, the hydrogel was able to mimic microtubule structures under physiological conditions and designed to release the functional small interfering RNA (siRNA)−aptamer complex (SAC) sequentially. In addition, we encoded restriction enzyme-responsive sites in DNA−RNA hybrid hydrogel to boost the release of SAC. This novel strategy provides an excellent platform for systematic RNA delivery through double-controlled release, SAC release from hydrogel, and subsequent release of siRNA from the SAC, which has promising potential in RNA therapy.

Nucleic acid-based artificial nanocarriers for gene therapy

“…The siRNA cargo in the network can be released by the substrate cleavage of a restriction enzyme, providing a new type of smart siRNA delivery strategy. 184…”

Application of Nucleic Acid Frameworks in the Construction of Nanostructures and Cascade Biocatalysts: Recent Progress and Perspective

“…Remarkably, by changing the orientation of DNA-DNA interaction parts, the shape of the hybrid nanostructures could be easily changed from fiber to triangle with different physiochemical and immunological properties. Lee et al constructed an ultrasoft DNA-RNA hybrid hydrogel with the products of rolling circle amplification (RCA) and rolling circle transcription (RCT) for the delivery of siRNA-aptamer complex (SAC) (Han et al, 2020). The sequence responsible for the production of the DNA aptamer targeting nucleolin was included in the template of RCA, while the sequence responsible for the production of the siRNA was included in the template of RCT.…”

Injectable DNA Hydrogel-Based Local Drug Delivery and Immunotherapy

“…However, siRNA is easily degraded by nucleases in the humoral environment [ 65 ]. To this end, Lee et al constructed DNA-RNA hybrid hydrogels for tumor-targeted siRNA delivery via dual enzyme polymerization employing both rolling circle amplification (RCA) and rolling circle transcription (RCT) [ 66 ]. In their design, the hybridization of multimeric short hairpin RNAs (shRNAs, the product of RCT) and polyvalent functional DNA aptamers (the product of RCA) mediated the formation of the hydrogel, and in order to facilitate the release of functional small interfering RNA (siRNA)-aptamer complexes (SACs), restriction enzyme reaction sites were edited into the nucleic acid sequences ( Figure 2 B).…”

“…( B ) DNA-RNA hybrid hydrogel synthesized by dual polymerization process for tumor-targeted delivery of SAC. (Adapted with permission from [ 66 ]. Copyright (2021) American Chemical Society.)…”