Assessment of cholesterol-derived ionic copolymers as potential vectors for gene delivery

Synthetic-polymer-assisted antisense oligonucleotide delivery: targeted approaches for precision disease treatment

This review explores the recent advancements in polymer-assisted delivery systems for antisense oligonucleotides (ASOs) and their potential in precision disease treatment. Synthetic polymers have shown significant promise in enhancing the delivery, stability, and therapeutic efficacy of ASOs by addressing key challenges such as cellular uptake, endosomal escape, and reducing cytotoxicity. The review highlights key studies from the past decade demonstrating how these polymers improve gene silencing efficiencies, particularly in cancer and neurodegenerative disease models. Despite the progress achieved, barriers such as immunogenicity, delivery limitations, and scalability still need to be overcome for broader clinical application. Emerging strategies, including stimuli-responsive polymers and advanced nanoparticle systems, offer potential solutions to these challenges. The review underscores the transformative potential of polymer-enhanced ASO delivery in personalised medicine, emphasising the importance of continued innovation to optimise ASO-based therapeutics for more precise and effective disease treatments.

pH-Responsive Amphiphilic Carboxylate Polymers: Design and Potential for Endosomal Escape

The intracellular delivery of emerging biomacromolecular therapeutics, such as genes, peptides, and proteins, remains a great challenge. Unlike small hydrophobic drugs, these biotherapeutics are impermeable to the cell membrane, thus relying on the endocytic pathways for cell entry. After endocytosis, they are entrapped in the endosomes and finally degraded in lysosomes. To overcome these barriers, many carriers have been developed to facilitate the endosomal escape of these biomacromolecules. This mini-review focuses on the development of anionic pH-responsive amphiphilic carboxylate polymers for endosomal escape applications, including the design and synthesis of these polymers, the mechanistic insights of their endosomal escape capability, the challenges in the field, and future opportunities.

Translational Advances of Hydrofection by Hydrodynamic Injection

Hydrodynamic gene delivery has proven to be a safe and efficient procedure for gene transfer, able to mediate, in murine model, therapeutic levels of proteins encoded by the transfected gene. In different disease models and targeting distinct organs, it has been demonstrated to revert the pathologic symptoms and signs. The therapeutic potential of hydrofection led different groups to work on the clinical translation of the procedure. In order to prevent the hemodynamic side effects derived from the rapid injection of a large volume, the conditions had to be moderated to make them compatible with its use in mid-size animal models such as rat, hamster and rabbit and large animals as dog, pig and primates. Despite the different approaches performed to adapt the conditions of gene delivery, the results obtained in any of these mid-size and large animals have been poorer than those obtained in murine model. Among these different strategies to reduce the volume employed, the most effective one has been to exclude the vasculature of the target organ and inject the solution directly. This procedure has permitted, by catheterization and surgical procedures in large animals, achieving protein expression levels in tissue close to those achieved in gold standard models. These promising results and the possibility of employing these strategies to transfer gene constructs able to edit genes, such as CRISPR, have renewed the clinical interest of this procedure of gene transfer. In order to translate the hydrodynamic gene delivery to human use, it is demanding the standardization of the procedure conditions and the molecular parameters of evaluation in order to be able to compare the results and establish a homogeneous manner of expressing the data obtained, as ‘classic’ drugs.

The endocytic pathway and therapeutic efficiency of doxorubicin conjugated cholesterol-derived polymers

Previously synthesized poly(methacrylic acid-co-cholesteryl methacrylate) P(MAA-co-CMA) copolymers were examined as potential drug delivery vehicles.

Reductively-sheddable cationic nanocarriers for dual chemotherapy and gene therapy with enhanced release

The development of a versatile strategy to synthesize cationic nanocarriers capable of co-delivery and enhanced release of drugs and oligonucleotides is promising for synergic dual chemotherapy and gene therapy. Herein, we report a novel cationic amphiphilic diblock copolymer having a single reduction-responsive disulfide linkage at a junction between a FDA-approved polylactide (PLA) block and a cationic methacrylate block (C-ssABP). The amphiphilic design of the C-ssABP enables the formation of cationic micellar aggregates possessing hydrophobic PLA cores, encapsulating anticancer drugs; cationic coronas, ensuring complementary complexation with negatively-charged oligonucleotides through electrostatic interactions; and disulfides at interfaces, leading to enhanced release of both encapsulated drugs and complexed oligonucleotides. The reduction-responsive intracellular trafficking results from flow cytometry, confocal laser scanning microscopy, and cell viability, as well as in vitro gene transfection assay suggest that C-ssABP offers versatility as an effective nanocarrier platform for dual chemotherapy and gene therapy.