Carriers For Gene Therapy Research Articles

Targeted Nanocarrier-Based Drug Delivery Strategies for Improving the Therapeutic Efficacy of PARP Inhibitors against Ovarian Cancer.

The current focus of ovarian cancer (OC) research is the improvement of treatment options through maximising drug effectiveness. OC remains the fifth leading cause of cancer-induced mortality in women worldwide. In recent years, nanotechnology has revolutionised drug delivery systems. Nanoparticles may be utilised as carriers in gene therapy or to overcome the problem of drug resistance in tumours by limiting the number of free drugs in circulation and thereby minimising undesired adverse effects. Cell surface receptors, such as human epidermal growth factor 2 (HER2), folic acid (FA) receptors, CD44 (also referred to as homing cell adhesion molecule, HCAM), and vascular endothelial growth factor (VEGF) are highly expressed in ovarian cancer cells. Generation of active targeting nanoparticles involves modification with ligands that recognise cell surface receptors and thereby promote internalisation by cancer cells. Several poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) are currently used for the treatment of high-grade serous ovarian carcinomas (HGSOC) or platinum-sensitive relapsed OC. However, PARP resistance and poor drug bioavailability are common challenges, highlighting the urgent need to develop novel, effective strategies for ovarian cancer treatment. This review evaluates the utility of nanoparticles in ovarian cancer therapy, with a specific focus on targeted approaches and the use of PARPi nanocarriers to optimise treatment outcomes.

Cationic Polythiophene as Gene Carrier and Sonosensitizer for Sonodynamic Synergic Gene Therapy of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most lethal and highly malignant tumors. Sonodynamic therapy (SDT) is a new cancer treatment method. One of its unique advantages lies in the treatment of deep tumors due to its excellent tissue penetration ability caused by ultrasound (US). However, most sonosensitizers suffer from weak sonodynamic activity and poor tumor-targeting ability. In addition, small interfering RNA (siRNA) is a promising anticancer drug, and the efficacy of siRNA-based gene therapy largely depends on the cell impermeability of the gene carrier. Here, we designed and synthesized a cationic polythiophene derivative (PT2) that can be used as a siRNA carrier for gene therapy. Moreover, PT2 could generate singlet oxygen (1O2) and hydroxyl radicals (O2•-) under US irradiation, which suggests that PT2 could be used for SDT. Our study discovered that NUDT1 promoted HCC proliferation and inhibited intracellular ROS production. Therefore, si-NUDT1 was designed and synthesized. NUDT1 silencing can inhibit the proliferation of tumor cells and increase the production of intracellular ROS to further improve the efficacy of SDT. Then, si-NUDT1 assembled with PT2 and DSPE-PEG-FA to prepare a novel tumor-targeting nanodrug (PT2-siRNA@PEG-FA) for synergic SDT and gene therapy of HCC.

Acrylic acid and vinylamine copolymers: Anomalous acidity and association with short polyacids

Acrylic acid and vinylamine copolymers represent one of the simplest polyampholyte structures. The acid-base and solution properties of these copolymers are hardly studied, and there are no works devoted to the synthesis of a set of copolymers with different compositions. We have synthesized a set of acrylic acid and vinylamine copolymers containing from 21 to 95 mol% acrylic acid units. The copolymers show the hydrodynamic properties and solubility of typical polyampholytes. Potentiometric titration revealed unusual acid-base properties of the new copolymers. The addition of HCl to the copolymers in the form of sodium/potassium salt results in only partial protonation of carboxyl anions and amine groups, including the acidic range (pH 2.5). This abnormally high acidity of acrylic acid and vinylamine copolymers is probably due to the formation of strong intra- and intermolecular hydrogen or ionic bonds between partially protonated and protonated groups: ∼COO−+H3N∼, COOH∙∙∙:NH2∼, ∼H2N:∙∙∙ +H3N∼. Poly(vinylamine) and copolymers are able to stabilize curcumin in aqueous medium, significantly increasing its concentration in the neutral pH range. Polymers with high content of amine groups prevent curcumin degradation, probably by converting it to a more stable anionic form. New copolymers are promising substances for the creation of nucleic acid carriers for gene therapy and genetic engineering. The copolymer containing 21 % acrylic acid is comparable to poly(vinylamine) in terms of interaction with oligonucleotides, but yields more homogeneous polyplexes without the impurity of positively charged and potentially toxic particles.

Charge-Reversed Exosomes for Targeted Gene Delivery to Cartilage for Osteoarthritis Treatment.

Gene therapy has the potential to facilitate targeted expression of therapeutic proteins to promote cartilage regeneration in osteoarthritis (OA). The dense, avascular, aggrecan-glycosaminoglycan (GAG) rich negatively charged cartilage, however, hinders their transport to reach chondrocytes in effective doses. While viral vector mediated gene delivery has shown promise, concerns over immunogenicity and tumorigenic side-effects persist. To address these issues, this study develops surface-modified cartilage-targeting exosomes as non-viral carriers for gene therapy. Charge-reversed cationic exosomes are engineered for mRNA delivery by anchoring cartilage targeting optimally charged arginine-rich cationic motifs into the anionic exosome bilayer by using buffer pH as a charge-reversal switch. Cationic exosomes penetrated through the full-thickness of early-stage arthritic human cartilage owing to weak-reversible ionic binding with GAGs and efficiently delivered the encapsulated eGFP mRNA to chondrocytes residing in tissue deep layers, while unmodified anionic exosomes do not. When intra-articularly injected into destabilized medial meniscus mice knees with early-stage OA, mRNA loaded charge-reversed exosomes overcame joint clearance and rapidly penetrated into cartilage, creating an intra-tissue depot and efficiently expressing eGFP; native exosomes remained unsuccessful. Cationic exosomes thus hold strong translational potential as a platform technology for cartilage-targeted non-viral delivery of any relevant mRNA targets for OA treatment.

Impact of DNA on interactions between core proteins of Hepatitis B virus-like particles comprising different C-terminals

Hepatitis B virus (HBV) virus-like particles (VLPs) are promising therapeutic agents derived from HBV core proteins (Cp). This study investigates the assembly dynamics of HBV VLPs, which is crucial for their potential as drug carriers or gene delivery systems. Coarse-grained molecular dynamics simulations explore the impact of C-terminal domain length (in the Cp ranging from Cp149 to wild-type Cp183) on Cp assembly and stability, particularly in the presence of DNA. Our findings reveal that the C-terminal nucleic acid binding region significantly influences Cp assembly and stability of trimers comprising Cp dimers. Shorter C-terminal domains (Cp164, Cp167) enhance stability and protein-protein interactions, while interactions between naturally occurring Cp183 are destabilized in the absence of DNA. Interestingly, DNA addition further stabilizes Cp assemblies, and this effect is influenced by the length of the nucleic acid binding region. Shorter C-terminal domains show less dependency on DNA content. This stabilization is attributed to electrostatic forces between positively charged C-terminal chains and negatively charged nucleic acids. Our study sheds light on the molecular mechanisms governing protein-protein and protein-DNA interactions in HBV VLP assembly, providing insights into Cp processability and informing the development of efficient gene therapy carriers using VLP technology.

ShRNA Targeting Lentiviral Vector Minus-Strand Product Improves the Viral Titer During Viral Packaging.

Lentiviral vector (LVV) has been used as one of the common carriers for gene therapy in clinical trials. LVV-mediated clinical trials have being reported in successfully treating hundreds of β-thalassemia cases. These LVVs bear an inversely placed β-hemoglobin (HBB) gene expression cassette for preserving introns during the viral RNA packaging. Consequently, these LVVs often produce a small amount of negatively orientated transcript driven by its internal gene promoter and would lower the viral titer by the minus-strand complemented with the viral backbone. To overcome this problem, we designed shRNAs specifically target the minus-strand RNA driven by the LVV internal promoter that resulted in a notable increase in the viral titer. This report demonstrates a simple and positive mean for increasing the effectiveness for gene therapy with the LVV system.

Adeno-associated virus vector hydrogel formulations for brain cancer gene therapy applications

Gelatin-based formulations are utilized in neurosurgical procedures, with Medisponge® serving as an illustration of a secure and biocompatible hemostatic formulation. Noteworthy are combined hemostatic products that integrate pharmacological agents with gelatin. Gelatin matrices, which host biologically active substances, provide a platform for a variety of molecules. Biopolymers function as carriers for chemicals and genes, a facet particularly pertinent in brain cancer therapy, as gene therapy complement conventional approaches. The registration of Zolgensma underscores the efficacy of rAAV vectors in therapeutic gene delivery to the CNS. rAAVs, renowned for their safety, stability, and neuron-targeting capabilities, predominate in CNS gene therapy studies. The effectiveness of rAAV vector therapy varies based on the serotype and administration route. Local gene therapy employing hydrogel (e.g., post-tumor resection) enables the circumvention of the blood-brain barrier and restricts formulation diffusion. This study formulates gelatin rAAV gene formulations and evaluates vector transduction potential. Transduction efficiency was assessed using ex vivo mouse brains and in vitro cancer cell lines. In vitro, the transduction of rAAV vectors in gelatin matrices was quantified through qPCR, measuring the itr and Gfp expression. rAAVDJ and rAAV2 demonstrated superior transduction in ex vivo and in vitro models. Among the cell lines tested (Hs683, B16-F10, NIH:OVCAR-3), gelatin matrix F1 exhibited selective transduction, particularly with Hs683 human glioma cells, surpassing the performance Medisponge®. This research highlights the exploration of local brain cancer therapy, emphasizing the potential of gelatin as an rAAV vector carrier for gene therapy. The functional transduction activity of gelatin rAAV formulations is demonstrated.

Intravenous Injection of PEI-Decorated Iron Oxide Nanoparticles Impacts NF-kappaB Protein Expression in Immunologically Stressed Mice.

Nanoparticle-based formulations are considered valuable tools for diagnostic and treatment purposes. The surface decoration of nanoparticles with polyethyleneimine (PEI) is often used to enhance their targeting and functional properties. Here, we aimed at addressing the long-term fate in vivo and the potential "off-target" effects of PEI decorated iron oxide nanoparticles (PEI-MNPs) in individuals with low-grade and persistent systemic inflammation. For this purpose, we synthesized PEI-MNPs (core-shell method, PEI coating under high pressure homogenization). Further on, we induced a low-grade and persistent inflammation in mice through regular subcutaneous injection of pathogen-associated molecular patterns (PAMPs, from zymosan). PEI-MNPs were injected intravenously. Up to 7 weeks thereafter, the blood parameters were determined via automated fluorescence flow cytometry, animals were euthanized, and the organs analyzed for iron contents (atomic absorption spectrometry) and for expression of NF-κB associated proteins (p65, IκBα, p105/50, p100/52, COX-2, Bcl-2, SDS-PAGE and Western blotting). We observed that the PEI-MNPs had a diameter of 136 nm and a zeta-potential 56.9 mV. After injection in mice, the blood parameters were modified and the iron levels were increased in different organs. Moreover, the liver of animals showed an increased protein expression of canonical NF-κB signaling pathway members early after PEI-MNP application, whereas at the later post-observation time, members of the non-canonical signaling pathway were prominent. We conclude that the synergistic effect between PEI-MNPs and the low-grade and persistent inflammatory state is mainly due to the hepatocytes sensing infection (PAMPs), to immune responses resulting from the intracellular metabolism of the uptaken PEI-MNPs, or to hepatocyte and immune cell communications. Therefore, we suggest a careful assessment of the safety and toxicity of PEI-MNP-based carriers for gene therapy, chemotherapy, and other medical applications not only in healthy individuals but also in those suffering from chronic inflammation.

Second-Generation Polyamidoamine Dendrimer Conjugated with Oligopeptides Can Enhance Plasmid DNA Delivery In Vitro.

Poly(amidoamine) (PAMAM) dendrimers have attracted considerable attention in the field of gene therapy due to their flexibility in introducing different functional moieties and reduced toxicity at low generations. However, their transfection efficiency remains a limitation. Therefore, an essential approach for improving their transfection efficiency as gene carriers involves modifying the structure of PAMAM by conjugating functional groups around their surface. In this study, we successfully conjugated an RRHRH oligopeptide to the surface of PAMAM generation 2 (PAMAM G2) to create RRHRH-PAMAM G2. This construction aims to condense plasmid DNA (pDNA) and facilitate its penetration into cell membranes, leading to its promising potential for gene therapy. RRHRH-PAMAM G2/pDNA complexes were smaller than 100 nm and positively charged. Nano-polyplexes can enter the cell and show a high transfection efficiency after 24 h of transfection. The RRHRH-PAMAM G2 was non-toxic to HeLa, NIH3T3, A549, and MDA-MB-231 cell lines. These results strongly suggest that RRHRH-PAMAM G2 holds promise as a gene carrier for gene therapy owing to its biocompatibility and ability to deliver genes to the cell.

Application of Chitosan-Based Polysaccharide Biomaterials in Tissue Engineering

Chitosan-based polysaccharide biomaterials have gained interest as viable options in tissue engineering due to their distinctive properties and wide range of potential applications. Biomaterials play a crucial role in regenerative medicine because they foster an environment conducive to cell growth and tissue repair. The chitin-derived polysaccharide chitosan is superior than synthetic materials in several ways: it has a similar structure to the extracellular matrix, is biocompatible, biodegradable, antimicrobial, and can incorporate bioactive chemicals. In this article, check how chitosan can be used in tissue engineering as a scaffold for different types of tissue, a hydrogel for wound healing, and a carrier for gene therapy, stem cell culture, and drug delivery. Scaffolds made from chitosan have shown tremendous promise in tissue engineering for the neurological system, bone and cartilage transplantation, and skin regeneration. Hydrogels made from chitosan have been shown to be useful in treating wounds and stopping bleeding. Chitosan's medicinal potential in gene therapy, stem cell culture, and targeted medication administration is further enhanced by the addition of bioactive components such as growth factors, genes, or medicines. In addition, using chitosan in tissue engineering can pave the way for future developments in stem cell techniques, nanotechnology, biofabrication, and 3D bioprinting, among other areas of study. These advances may one day lead to individualized and highly effective therapies for tissue repair and regeneration. The use of chitosan in tissue engineering has the potential to advance regenerative medicine and address the growing demand for more effective techniques to heal damaged tissues. Tissue engineers can revolutionize the field of regenerative medicine and enhance patient outcomes by taking use of chitosan's adaptability and bioactivity to create cutting-edge biomaterials and therapeutic techniques.

A polymer nanoplatform with high transfection rate for the efficient gene therapy of peripheral arterial diseases

Gene therapy has great potential in the treatment of peripheral arterial diseases (PAD). However, the commercial used carrier for gene therapy, polyethyleneimine (PEI) 25 kDa is not efficient in transfection in vivo and is difficult to degrade. In this work, PEI 1.8 kDa was cross-linked with glutaraldehyde, and glutaraldehyde-PEI (GAPEI) was obtained by a simple wet chemistry synthetic process. The prostacyclin synthase (PTGIS) plasmid was further wrapped by GAPEI to form a polymer with a size of ∼150 nm and a positive potential for transfection. The western blotting experiment showed that the level of PTGIS protein synthesis in cells transfected by GAPEI was 1.48 times higher than that of PEI25kDa. He cytotoxicity test showed that GAPEI had lower cytotoxicity. In vitro and in vivo experiments showed a significant increase in locally secreted prostacyclin (PGI2) after transfection of PTGIS plasmid. The ability of cells to establish tube and chemotaxis to stem cells increased, and these phenotypic changes may be involved in the vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGF-β1), and fibroblast growth factor 2 (FGF2) pathways. This work promotes the potential applications of GAPEI-PTGIS nanoparticles for PAD therapy and provides design concepts for the synthesis of therapeutic agents for PAD therapy.

Complexes formed between polyelectrolyte and acetylated cationic dendrimers

Gene therapies are receiving a revival, especially because of the potential for use in cancer and infectious disease vaccination. However, effectively condensing and maintaining deoxyribonucleic acid (DNA) carriers for gene therapy are used, such as dendrimers. The penetrable sphere model developed by Qamhieh et al., explain the interaction between linear polyelectrolyte (LPE) and an ion-penetrable sphere was employed to study the complexation of negatively charged DNA and acetylated dendrimer. Throughout the study, we emphasized the effect of acetylation on two types of complexations: single dendrimer-DNA chain complex and multiple dendrimers-DNA chain complex. The interaction between three different DNA lengths: L = 90 nm of 265; L = 184 nm of 541 bp; and L = 680 nm of 2000 bp individually with the poly (amido amine) (PAMAM) dendrimer of generation 5 was studied. For a single dendrimer-DNA complex, the number of condensed monomers around the dendrimer and the fraction of optimal length wrapping around the dendrimer was studied. It was found that by increasing acetylation, the number of condensed monomers and the fraction of optimal length decreased. For multiple dendrimers-DNA complex, the optimal length wrapping around the dendrimer and the linker that forms between complexes were studied. As a result, with increasing acetylation, the will shorten while the linker will increase significantly. The acetylation also affected the number of turns wrapping around the dendrimer and the net charge of the complex for single and multiple dendrimer-DNA complexes, and it was found that the longer the chain length, the more turns there are around the dendrimer. The net charge of all complexes was negative due to increased acetylation. In this study, it is revealed that the developed model is suitable for demonstrating the complexation between the dendrimer and the DNA.

Non-Viral Carriers for Nucleic Acids Delivery: Fundamentals and Current Applications.

Over the past decades, non-viral DNA and RNA delivery systems have been intensively studied as an alternative to viral vectors. Despite the most significant advantage over viruses, such as the lack of immunogenicity and cytotoxicity, the widespread use of non-viral carriers in clinical practice is still limited due to the insufficient efficacy associated with the difficulties of overcoming extracellular and intracellular barriers. Overcoming barriers by non-viral carriers is facilitated by their chemical structure, surface charge, as well as developed modifications. Currently, there are many different forms of non-viral carriers for various applications. This review aimed to summarize recent developments based on the essential requirements for non-viral carriers for gene therapy.

Polysaccharides: A Carrier for Gene Therapy.

Recently, polysaccharides have been proved to be an interesting drug delivery system as gene carriers, and natural polysaccharides have attracted more attention in the field of biomaterials due to their unique non-toxicity, good biocompatibility, and biodegradability. Compared with other polysaccharides, chitosan and dextran have more extensive and profound applications and can directly or indirectly deliver therapeutic genes. Chinese medicinal polysaccharides often do not have cationic groups and cannot directly deliver therapeutic genes. They usually need certain chemical modifications. The operation process is difficult, but better therapeutic effects are achieved. In this paper, the classification of polysaccharides and the research progress in modified polysaccharides as novel gene carriers are reviewed to provide a reference for polysaccharides as novel gene carriers in gene therapy. Moreover, efficient transfection of DNA and RNA therapeutic genes requires the development of new efficient and low-toxic vectors as well as the optimization of existing delivery vectors. Therefore, the research on polysaccharide gene vector has a long way to go and has good prospects in scientific research and biomedicine.

A miRNA-based gene therapy nanodrug synergistically enhances pro-inflammatory antitumor immunity against melanoma

MicroRNA (miRNA)-based gene therapy is a robust approach to treating human cancers. However, the low target specificity and safety issues associated with viral vectors have limited the clinical use of miRNA therapeutics. In the present study, we aimed to develop a biocompatible nanocarrier to deliver the tumor suppressor miR-30a-5p for gene therapy of ocular melanoma. The quasi-mesoporous magnetic nanospheres (MMNs) were prepared by polyelectrolytes-mediated self-assembling Fe3O4 nanocrystals; the cationic polymer capped quasi-mesoporous inner tunnels of the MMNs facilitate high miRNA loading and protect from nuclease degradation. Then, the outer layer of the MMNs was modified with a disulfide bond bridged very low molecular weight polyethyleneimine (PEI) network to form redox-responsive nanospheres (rMMNs) that enhance the miRNA payload and enable miRNA release under glutathione-dominant tumor microenvironment. The miR-30a-5p loaded rMMNs nanodrug (miR-30a-5p@rMMNs) upregulated miR-30a-5p level and inhibited malignant phenotypes of ocular melanoma by targeting the transcription factor E2F7 both in vitro and in vivo. Additionally, rMMNs act as an enhancer to increase cancer cell apoptosis by modulating M1-like macrophage polarization and activating Fenton reaction. Thus, the rMMNs is a promising miRNA carrier for gene therapy and could enhance pro-inflammatory immunity in melanoma and other cancers. Statement of significance• miR-30a-5p@rMMNs inhibited malignant phenotypes of ocular melanoma both in vitro and in vivo.• The rMMNs promoted M1 macrophage polarization thus synergistically enhancing pro-inflammatory anti-tumor immunity against melanoma.• The rMMNs showed no obvious toxicity under the injection dose.

Preclinical gene therapy in glioblastoma multiforme: Using olfactory ensheathing cells containing a suicide gene

AimsGlioblastoma multiforme (GBM) is the most malignant type of brain tumor resistant to current treatments. Recently, suicide gene therapy with the Herpex Simplex Virus thymidine kinase (HSV-tk) gene has been developed with high therapeutic potency, even in clinical trials. The primary challenge to establishing a gene therapy strategy is how to transfer the desired gene into the tumor site. The olfactory ensheathing cells (OECs) secreting neurotropic and anti-inflammatory factors have a high migration capacity, making them applicable for gene therapy. We examined our new construct OECs containing the HSV-tk gene for their migration and tumoricidal ability in animal models of GBM. Main methodsIsolated OECs were transduced by the HSV-tk gene (OEC-tks). OEC-tks or PBS were injected ipsilaterally or contralaterally into the tumor-bearing rats, followed by gancyclovir (GCV) or PBS administration. At the end of the treatment, tumor size, apoptosis, and animal survival were assessed. Key findingsOur findings demonstrated that tumor size was significantly decreased in OEC-tks ipsilateral and contralateral groups, followed by GCV injections. Furthermore, both groups' pro-apoptotic protein and gene expressions were up-regulated, whereas Bcl-2 protein expression was down-regulated. Besides, apoptosis in the OEC-tks ipsilateral/GCV group was higher in the intratumoral region, and this percentage was higher in the OEC-tks contralateral/GCV group in the peritumoral region. Interestingly, our new construct increased animal survival rate and reduced body weight loss. SignificanceOECs could serve as a novel carrier for gene therapy, have a high migration capability to the GBM and eventually suppress tumor progression.

Design of Cyclic Peptide-Based Nanospheres and the Delivery of siRNA.

In recent years, cyclic peptides have attracted much attention due to their chemical and enzymatic stability, low toxicity, and easy modification. In general, the self-assembled nanostructures of cyclic peptides tend to form nanotubes in a cyclic stacking manner through hydrogen bonding. However, studies exploring other assembly strategies are scarce. In this context, we proposed a new assembly strategy based on cyclic peptides with covalent self-assembly. Here, cyclic peptide-(DPDPDP) was rationally designed and used as a building block to construct new assemblies. With cyclo-(DP)3 as the structural unit and 2,2′-diamino-N-methyldiethylamine as the linker, positively charged nanospheres ((CP)6NS) based on cyclo-(DP)3 were successfully constructed by covalent self-assembly. We assessed their size and morphology by scanning electron microscopy (SEM), TEM, and DLS. (CP)6NS were found to have a strong positive charge, so they could bind to siRNA through electrostatic interactions. Confocal microscopy analysis and cell viability assays showed that (CP)6NS had high cellular internalization efficiency and low cytotoxicity. More importantly, real-time polymerase chain reaction (PCR) and flow cytometry analyses indicated that (CP)6NS-siRNA complexes potently inhibited gene expression and promoted tumor cell apoptosis. These results suggest that (CP)6NS may be a potential siRNA carrier for gene therapy.

Materiomically Designed Polymeric Vehicles for Nucleic Acids: Quo Vadis?

Despite rapid advances in molecular biology, particularly in site-specific genome editing technologies, such as CRISPR/Cas9 and base editing, financial and logistical challenges hinder a broad population from accessing and benefiting from gene therapy. To improve the affordability and scalability of gene therapy, we need to deploy chemically defined, economical, and scalable materials, such as synthetic polymers. For polymers to deliver nucleic acids efficaciously to targeted cells, they must optimally combine design attributes, such as architecture, length, composition, spatial distribution of monomers, basicity, hydrophilic-hydrophobic phase balance, or protonation degree. Designing polymeric vectors for specific nucleic acid payloads is a multivariate optimization problem wherein even minuscule deviations from the optimum are poorly tolerated. To explore the multivariate polymer design space rapidly, efficiently, and fruitfully, we must integrate parallelized polymer synthesis, high-throughput biological screening, and statistical modeling. Although materiomics approaches promise to streamline polymeric vector development, several methodological ambiguities must be resolved. For instance, establishing a flexible polymer ontology that accommodates recent synthetic advances, enforcing uniform polymer characterization and data reporting standards, and implementing multiplexed in vitro and in vivo screening studies require considerable planning, coordination, and effort. This contribution will acquaint readers with the challenges associated with materiomics approaches to polymeric gene delivery and offers guidelines for overcoming these challenges. Here, we summarize recent developments in combinatorial polymer synthesis, high-throughput screening of polymeric vectors, omics-based approaches to polymer design, barcoding schemes for pooled in vitro and in vivo screening, and identify materiomics-inspired research directions that will realize the long-unfulfilled clinical potential of polymeric carriers in gene therapy.

PEI-PEG-Coated Mesoporous Silica Nanoparticles Enhance the Antitumor Activity of Tanshinone IIA and Serve as a Gene Transfer Vector.

Tanshinone IIA (TanIIA) and gene therapy both hold promising potentials in hepatocellular carcinoma (HCC) treatment. However, low solubility and poor bioavailability of TanIIA limit its clinical application. Similarly, gene therapy with GPC3-shRNA, a type of short hairpin RNAs (shRNAs) capable of silencing the glypican-3 (GPC3) expression, is seriously limited due to its susceptibility to nuclease degradation and high off-target effects. In the present study, polyethyleneimine (PEI)-polyethylene glycol (PEG)-coated mesoporous silica nanoparticles (MSN-PEG) were used as a drug carrier. By encapsulating TanIIA into MSN-PEG, we synthesized MSN-TanIIA-PEG nanoparticles and observed the involved characteristics. This was followed by exploration of antitumor activity on the HepG2 cell lines in vitro. Meanwhile, in order to construct GPC3-shRNA plasmids, a shRNA sequence targeting GPC3 was synthesized and cloned into the pSLenti-U6 vector. Accordingly, the performance of MSN-PEG as a gene transfer carrier for GPC3-shRNA gene therapy of HCC in vitro was evaluated, including transfection efficiency and DNA binding biological characteristics. The results indicated successful encapsulation of TanIIA in MSN-PEG, which had satisfactory efficacy, favorable dispersity, suitable particle size, and sustained release effect. The in vitro anti-HCC effects of nano-TanIIA were greatly improved, which outperformed free-TanIIA in terms of proliferation and invasion inhibition, as well as apoptosis induction of HCC cells. As expected, MSN-PEG possessed excellent gene delivery capacity with good binding, release, and protection from RNase digestion. Using MSN-PEG as a gene carrier, the plasmids were successfully transfected into HepG2 cells, and both the mRNA and protein expressions of GPC3 were significantly downregulated. It was thus concluded that a sustained release TanIIA delivery system for HCC treatment was synthesized and that MSN-PEG could also serve as a gene transfer carrier for gene therapy. More interestingly, MSN-PEG may be a potential delivery platform that combines TanIIA and GPC3-shRNA together to enhance their synergistic effect.

Carbon Dioxide-Derived Biodegradable and Cationic Polycarbonates as a New siRNA Carrier for Gene Therapy in Pancreatic Cancer.

Pancreatic cancer is an aggressive malignancy associated with poor prognosis and a high tendency in developing infiltration and metastasis. K-ras mutation is a major genetic disorder in pancreatic cancer patient. RNAi-based therapies can be employed for combating pancreatic cancer by silencing K-ras gene expression. However, the clinical application of RNAi technology is appreciably limited by the lack of a proper siRNA delivery system. To tackle this hurdle, cationic poly (cyclohexene carbonate) s (CPCHCs) using widely sourced CO2 as the monomer are subtly synthesized via ring-opening copolymerization (ROCOP) and thiol-ene functionalization. The developed CPCHCs could effectively encapsulate therapeutic siRNA to form CPCHC/siRNA nanoplexes (NPs). Serving as a siRNA carrier, CPCHC possesses biodegradability, negligible cytotoxicity, and high transfection efficiency. In vitro study shows that CPCHCs are capable of effectively protecting siRNA from being degraded by RNase and promoting a sustained endosomal escape of siRNA. After treatment with CPCHC/siRNA NPs, the K-ras gene expression in both pancreatic cancer cell line (PANC-1 and MiaPaCa-2) are significantly down-regulated. Subsequently, the cell growth and migration are considerably inhibited, and the treated cells are induced into cell apoptotic program. These results demonstrate the promising potential of CPCHC-mediated siRNA therapies in pancreatic cancer treatment.