Polymeric nanoparticles for dual-targeted theranostic gene delivery to hepatocellular carcinoma

Somatostatin receptor-targeted polymeric nanoplatform for efficient CRISPR/Cas9 gene editing to enhance synergistic hepatocellular carcinoma therapy

INTRODUCTION

The CRISPR/Cas9 system-based gene therapy can fundamentally address the issues of cancer occurrence, development, progression, and metastasis. However, the lack of targeting and effectiveness hinders gene therapy from entering clinical application. Herein, a somatostatin receptor-targeted polymeric nanoplatform is developed for the delivery of a PD-L1-targeted CRISPR/Cas9 system and synergistic treatment of hepatocellular carcinoma. This nanoplatform can effectively incorporate the CRISPR/Cas9 system and the chemotherapeutic drug paclitaxel to simultaneously address the biological safety and packaging capacity issues of viral vectors. After the octreotide-modified polymer (LNA-PEG-OCT) guided the nanoparticle into hepatoma carcinoma cells, the nanoparticle protected the CRISPR/Cas9 ribonucleoprotein complex (RNP) and achieved lysosomal escape. Then, the RNP reached the target gene (PD-L1) under the guidance of the single guide RNA (sgRNA) in the RNP. The PD-L1 gene editing efficiency reached up to 55.8% for HepG2 cells in vitro and 46.0% for tumor tissues in vivo, leading to effective suppression of PD-L1 protein expression. Substantial inhibition of hepatocellular carcinoma cell proliferation and further 79.45% growth repression against subcutaneous xenograft tumors were achieved. Overall, this somatostatin receptor-targeted polymeric nanoplatform system not only provides a promising nanocarrier for CRISPR/Cas9 system delivery, but also expands the potential of combining gene editing and chemotherapy.

The Whole Is Greater than the Sum of Its Parts - Challenges and Perspectives in Polyelectrolytes

Polyelectrolytes offer unique properties for biological applications due to their charged nature and high water solubility. Here, the challenges in their synthesis and characterization techniques are reviewed, emphasizing that their strong interactions with the surrounding media and counterions must be considered when working with this interesting class of materials. Their potential in complexation for gene delivery, their unique stealth and anti-fouling properties, and their more specific interactions with amino acid transporters for cancer therapy are highlighted. The underlying mechanisms responsible for their biological efficacy, including the proton sponge effect for endosomal release and their interactions with cellular membranes, are addressed. For polyelectrolytes with a high level of usage, an overview is given of their historical context. This Perspective outlines the potential of polyelectrolytes for innovative applications in the field of biomedicine. Considering the physicochemical characteristics of this class of materials, this work strives to elucidate the distinctive properties and applications of polyelectrolytes.

Advanced Polymeric Nanoparticles for Cancer Immunotherapy: Materials Engineering, Immunotherapeutic Mechanism and Clinical Translation

Cancer immunotherapy, which leverages immune system components to treat malignancies, has emerged as a cornerstone of contemporary therapeutic strategies. Yet, critical concerns about the efficacy and safety of cancer immunotherapies remain formidable. Nanotechnology, especially polymeric nanoparticles (PNPs), offers unparalleled flexibility in manipulation-from the chemical composition and physical properties to the precision control of nanoassemblies. PNPs provide an optimal platform to amplify the potency and minimize systematic toxicity in a broad spectrum of immunotherapeutic modalities. In this comprehensive review, the basics of polymer chemistry, and state-of-the-art designs of PNPs from a physicochemical standpoint for cancer immunotherapy, encompassing therapeutic cancer vaccines, in situ vaccination, adoptive T-cell therapies, tumor-infiltrating immune cell-targeted therapies, therapeutic antibodies, and cytokine therapies are delineated. Each immunotherapy necessitates distinctively tailored design strategies in polymeric nanoplatforms. The extensive applications of PNPs, and investigation of their mechanisms of action for enhanced efficacy are particularly focused on. The safety profiles of PNPs and clinical research progress are discussed. Additionally, forthcoming developments and emergent trends of polymeric nano-immunotherapeutics poised to transform cancer treatment paradigms into clinics are explored.

Current advances in nanoparticle-based approaches for the hepatocellular carcinoma treatment

Hepatocellular carcinoma (HCC) is the most common form of liver (LC) with a high mortality rate, driven by risk factors including viral hepatitis, alcoholic liver disease, and nonalcoholic steatohepatitis. The incident of HCC increases 2-4% of the worldwide population each year which would most certainly exceed one million per year by 2025. Despite advances in our knowledge, 25% of HCC tumors have actionable mutations which demands for innovative treatments strategies. In this perspective, we are providing a comprehensive summary of nanoparticles (NPs) based therapeutic approaches for HCC. We begin with an overview of HCC, concentrating on its pathogenesis, current conventional therapies, and their limitations. Then we delve into the therapeutic application of various nanoparticles (NPs) platforms for HCC, including polymeric micelles, dendrimers, liposomes, solid-lipid nanoparticles, nanostructured lipid carriers, exosomes, niosomes, mesoporous silica nanoparticles, carbon nanotubes. Special attention is given to the application of NPs in photothermal and photodynamic treatment was also investigated, with a focus on their effectiveness in targeted cancer ablation. Additionally, the review discusses recent patents and clinical studies that demonstrate the promise of NPs-based therapies in improving HCC treatment outcomes. This article underscores the potential of NPs based technologies to address the challenges faced by traditional therapies and offers insights into future directions for HCC management.

Synthesis and characterization of poly (β-amino ester) polyplex nanocarrier with high encapsulation and uptake efficiency: impact of extracellular conditions

BACKGROUND

Poly (β-amino Ester) nanocarriers show promise for gene therapy, but their effectiveness can be limited by the environment within the body. This study aims to understand how common cell culture media components affect optimized PBAE nanocarrier performance in gene delivery.

METHODS

Optimized PBAE was synthesized based on Michael addition reaction and characterized by different assays, this study employed techniques like DLS and TEM to characterize PBAE nanocarriers, followed by cellular uptake analysis (flow cytometry and confocal imaging) and evaluation of gene expression under different polymer/DNA ratio ratios and media conditions.

RESULTS

The nanocarriers exhibited size under 200 nm and surface positive charge, with high encapsulation efficiency (up to 95%). Cellular uptake, transfection efficiency, and cytotoxicity were evaluated. Flow cytometry analysis revealed high cellular uptake (over 77% at 1 hour and up to 95% after 3 hours) and good viability. Transfection efficiency reached up to 80% with 2 μg DNA, particularly at weight ratios of 60 and 90.

CONCLUSION

The study also identified factors affecting transfection efficiency, including serum concentration and antibiotics in the culture medium, highlighting the importance of optimizing these conditions for future applications.

Suprachoroidal Delivery of Viral and Nonviral Vectors for Treatment of Retinal and Choroidal Vascular Diseases

PURPOSE

Current treatments for retinal and choroidal neovascular diseases suffer from insufficient durability, including anti-vascular endothelial growth factor-A agents. It is, therefore, of interest to explore alternative methods that could allow for robust improvement in visual acuity with fewer injections required.

DESIGN

Literature review.

RESULTS

Among various preclinical and clinical studies in the literature, a promising approach is the use of suprachoroidal injection with viral and nonviral gene delivery vectors. Compared with other ocular injection methods, suprachoroidal injection has demonstrated wide biodistribution of injected agents and safety as an outpatient procedure. In terms of viral vectors, suprachoroidal injection of an adeno-associated virus 8 vector expressing an anti-vascular endothelial growth factor-A antibody fragment has shown an excellent safety profile and evidence of biological activity. In terms of nonviral vectors, lipid nanoparticles and polymeric nanoparticles both demonstrate strong promise for ocular gene therapy in large animal models. In particular, biodegradable poly(β-amino ester) nanoparticles show excellent biodistribution, safety, and efficacy for gene therapy via the suprachoroidal route. Nonviral nanoparticle approaches can have notable advantages over viral vectors in terms of carrying capacity, redosability, and manufacturing costs. An advantage of gene therapy is that once a delivery vector has been optimized, genetic cargos can be readily tailored without changing the safety, efficacy, and pharmacokinetic properties of the delivery vector.

CONCLUSIONS

This review highlights recent progress that has been made and compares viral and nonviral suprachoroidal gene delivery for the treatment of retinal and choroidal vascular diseases. Suprachoroidal gene therapy is an emerging biotechnology that holds substantial potential to make a translational impact in treating these diseases.

Nucleic acid-loaded poly(beta-aminoester) nanoparticles for cancer nano-immuno therapeutics: the good, the bad, and the future

Immunotherapy has emerged as a promising approach to cancer treatment, offering improved survival rates and enhanced patients' quality of life. However, realizing the full potential of immunotherapy in clinical practice remains a challenge, as there is still plenty of room for modulating the complexity of the human immune system in favor of an antitumor immunogenicity. Nanotechnology, with its unique properties, holds promise in augmenting the efficacy of cancer immunotherapies in biotherapeutic protection and site- and time-controlled delivery of the immune modulator biologicals. Polymeric nanoparticles are promising biomaterials among different nanocarriers thanks to their robustness, versatility, and cost-efficient design and production. This perspective paper overviews critical concepts in nanometric advanced delivery systems applied to cancer immunotherapy. We focus on a detailed exploration of the current state of the art and trends in using poly(beta-aminoester) (pBAE) polymers for nucleic acid-based antitumor immunotherapies. Through different examples of the use of pBAE polymers reported in the literature, we revise the main advantages these polymers offer and some challenges to overcome. Finally, the paper provides insights and predictions on the path toward the clinical implementation of cancer nano-immunotherapies, highlighting the potential of pBAE polymers for advancements in this field.

Self-targeted smart polyester nanoparticles for simultaneous Delivery of photothermal and chemotherapeutic agents for efficient treatment of HCC

Advances in nanotechnology offer promising strategies to overcome the limitations of single-drug therapies in hepatocellular carcinoma (HCC) and other cancers such as multidrug resistance and variable drug tolerances. This study proposes a targeted nanoparticle system based on a poly(β-aminoester) (PβAE) core and a hyaluronic acid (HA) shell, designed for the codelivery of doxorubicin (DOX) and indocyanine green (ICG) to effectively treat HCC. These nanoparticles demonstrated remarkable physicochemical and colloidal stability, pH- and temperature-responsive release, enhanced cellular uptake, and drug retention within tumors. Upon near-infrared (NIR) irradiation, the photothermal conversion of ICG elevated local tumor temperatures up to 53.6 °C, enhancing apoptotic cell death significantly compared to chemotherapy alone (p < 0.05). Furthermore, the dual delivery system significantly enhanced therapeutic efficacy, as evidenced by a marked decrease in tumor growth in vivo compared to controls (p < 0.01). These findings illustrate that the HA/PβAE/DOX/ICG nanoparticles are not only able to precisely target tumor cells but also overcome the limitations associated with traditional chemotherapies and photothermal treatments, suggesting a promising avenue for clinical translation of cancer therapy.

Combinatorial Synthesis of Alkyl Chain-Capped Poly(β-Amino Ester)s for Effective siRNA Delivery

Poly (β-amino ester) (PBAE) is a class of biodegradable polymers containing ester bonds in their main chain, extensively investigated as cationic polymer carriers for siRNA. Most current PBAE carriers rely on termination with hydrophilic or charged amines. In this study, a polymer platform consisting of 168 PBAE polymers with hydrophobic alkyl chain terminals is constructed through sequential aza-Michael addition. A large number of effective carriers are identified through in vitro screening of the PBAE platform for siLuc delivery to HeLa-Luc cells. Specifically, PA8-C6 and PA8-C8 achieve remarkable gene knockdown efficacies of up to 80% with low cytotoxicity. Certain materials from the PA2 and PA5 series demonstrate potent siRNA delivery capabilities associated with elevated cytotoxicity. The pKa value of PBAE is predominantly determined by the hydrophilic amine side chains rather than the end-capping groups. A pKa range of ≈6.2-6.5 may contribute to the excellent delivery capability for PA8 series carriers. The co-formulation of PBAE carriers with helper lipids leads to the reduced size and surface charges of the polyplex NPs with siRNA, consequently decreasing the cytotoxicity and enhancing siRNA delivery efficacy. These findings hold significant implications for the development of novel degradable polymer carriers for siRNA delivery.

Advanced nanomedicines for the treatment of age-related macular degeneration

The critical and unmet medical need for novel therapeutic advancements in the treatment of age-related macular degeneration (AMD) cannot be overstated, particularly given the aging global population and the increasing prevalence of this condition. Current AMD therapy involves intravitreal treatments that require monthly or bimonthly injections to maintain optimal efficacy. This underscores the necessity for improved approaches, prompting recent research into developing advanced drug delivery systems to prolong the intervals between treatments. Nanoparticle-based therapeutic approaches have enabled the controlled release of drugs, targeted delivery of therapeutic materials, and development of smart solutions for the harsh microenvironment of diseased tissues, offering a new perspective on ocular disease treatment. This review emphasizes the latest pre-clinical treatment options in ocular drug delivery to the retina and explores the advantages of nanoparticle-based therapeutic approaches, with a focus on AMD, the leading cause of irreversible blindness in the elderly.

Targeted Drug Delivery Strategies for the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks among the most prevalent malignant tumors, exhibiting a high incidence rate that presents a substantial threat to human health. The use of sorafenib and lenvatinib, commonly employed as single-agent targeted inhibitors, complicates the treatment process due to the absence of definitive targeting. Nevertheless, the advent of nanotechnology has injected new optimism into the domain of liver cancer therapy. Nanocarriers equipped with active targeting or passive targeting mechanisms have demonstrated the capability to deliver drugs to tumor cells with high efficiency. This approach not only facilitates precise delivery to the affected site but also enables targeted drug release, thereby enhancing therapeutic efficacy. As medical technology progresses, there is an increasing call for innovative treatment modalities, including novel chemotherapeutic agents, gene therapy, phototherapy, immunotherapy, and combinatorial treatments for HCC. These emerging therapies are anticipated to yield improved clinical outcomes for patients, while minimizing systemic toxicity and adverse effects. Consequently, the application of nanotechnology is poised to significantly improve HCC treatment. This review focused on targeted strategies for HCC and the application of nanotechnology in this area.

RNA nanomedicine in liver diseases

The remarkable impact of RNA nanomedicine during the COVID-19 pandemic has demonstrated the expansive therapeutic potential of this field in diverse disease contexts. In recent years, RNA nanomedicine targeting the liver has been paradigm-shifting in the management of metabolic diseases such as hyperoxaluria and amyloidosis. RNA nanomedicine has significant potential in the management of liver diseases, where optimal management would benefit from targeted delivery, doses titrated to liver metabolism, and personalized therapy based on the specific site of interest. In this review, we discuss in-depth the different types of RNA and nanocarriers used for liver targeting along with their specific applications in metabolic dysfunction-associated steatotic liver disease, liver fibrosis, and liver cancers. We further highlight the strategies for cell-specific delivery and future perspectives in this field of research with the emergence of small activating RNA, circular RNA, and RNA base editing approaches.

Application of PPAR Ligands and Nanoparticle Technology in Metabolic Steatohepatitis Treatment

Metabolic dysfunction-associated steatotic liver disease/steatohepatitis (MASLD/MASH) is a major disease worldwide whose effective treatment is challenging. Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily and function as ligand-activated transcription factors. To date, three distinct subtypes of PPARs have been characterized: PPARα, PPARβ/δ, and PPARγ. PPARα and PPARγ are crucial regulators of lipid metabolism that modulate the transcription of genes involved in fatty acid (FA), bile acid, and cholesterol metabolism. Many PPAR agonists, including natural (FAs, eicosanoids, and phospholipids) and synthetic (fibrate, thiazolidinedione, glitazar, and elafibranor) agonists, have been developed. Furthermore, recent advancements in nanoparticles (NPs) have led to the development of new strategies for MASLD/MASH therapy. This review discusses the applications of specific cell-targeted NPs and highlights the potential of PPARα- and PPARγ-targeted NP drug delivery systems for MASLD/MASH treatment.

Investigating the Anticancer and Antioxidant Potentials of a Polymer-Grafted Sodium Alginate Composite Embedded with CuO and TiO2 Nanoparticles

In this study, we conducted the synthesis of a composite material by grafting an acrylonitrile-co-styrene (AN-co-St) polymer into sodium alginate and incorporating CuO (copper oxide) and TiO2 (titanium dioxide) nanoparticles. The primary objective was to investigate the potential anticancer and antioxidant activities of the composite material. First, CuO and TiO2 nanoparticles were synthesized and characterized for their size, morphology, and surface properties. Subsequently, these nanoparticles were integrated into the sodium alginate matrix, which had been grafted with the AN-co-St polymer, resulting in the formation of the composite material. To confirm successful nanoparticle incorporation and assess the structural integrity of the composite, various techniques such as X-ray diffraction analysis (XRD), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) were employed. The composite material’s anticancer and antioxidant activities were then evaluated. In vitro cell viability assays using the HepG-2 cell line were performed to assess potential cytotoxic effects, while antioxidant (DPPH) assays were conducted to determine the composite’s ability to scavenge free radicals and protect against oxidative stress. Preliminary results indicate that the composite material demonstrated promising anticancer and antioxidant activities. The presence of CuO and TiO2 nanoparticles within the composite contributed to these effects, as these nanoparticles are known to possess anticancer and antioxidant properties. Furthermore, the grafting of the AN-co-St polymer into sodium alginate enhanced the overall performance and stability of the composite material.

Strategies for Improved pDNA Loading and Protection Using Cationic and Neutral LNPs with Industrial Scalability Potential Using Microfluidic Technology

Purpose

In recent years, microfluidic technologies have become mainstream in producing gene therapy nanomedicines (NMeds) following the Covid-19 vaccine; however, extensive optimizations are needed for each NMed type and genetic material. This article strives to improve LNPs for pDNA loading, protection, and delivery, while minimizing toxicity.

Methods

The microfluidic technique was optimized to form cationic or neutral LNPs to load pDNA. Classical "post-formulation" DNA addition vs "pre" addition in the aqueous phase were compared. All formulations were characterized (size, homogeneity, zeta potential, morphology, weight yield, and stability), then tested for loading efficiency, nuclease protection, toxicity, and cell uptake.

Results

Optimized LNPs formulated with DPPC: Chol:DOTAP 1:1:0.1 molar ratio and 10 µg of DOPE-Rhod, had a size of 160 nm and good homogeneity. The chemico-physical characteristics of cationic LNPs worsened when adding 15 µg/mL of pDNA with the "post" method, while maintaining their characteristics up to 100 µg/mL of pDNA with the "pre" addition remaining stable for 30 days. Interestingly, neutral LNPs formulated with the same method loaded up to 50% of the DNA. Both particles could protect the DNA from nucleases even after one month of storage, and low cell toxicity was found up to 40 µg/mL LNPs. Cell uptake occurred within 2 hours for both formulations with the DNA intact in the cytoplasm, outside of the lysosomes.

Conclusion

In this study, the upcoming microfluidic technique was applied to two strategies to generate pDNA-LNPs. Cationic LNPs could load 10x the amount of DNA as the classical approach, while neutral LNPs, which also loaded and protected DNA, showed lower toxicity and good DNA protection. This is a big step forward at minimizing doses and toxicity of LNP-based gene therapy.

Synthetic Cells Revisited: Artificial Cells Construction Using Polymeric Building Blocks

The exponential growth of research on artificial cells and organelles underscores their potential as tools to advance the understanding of fundamental biological processes. The bottom-up construction from a variety of building blocks at the micro- and nanoscale, in combination with biomolecules is key to developing artificial cells. In this review, artificial cells are focused upon based on compartments where polymers are the main constituent of the assembly. Polymers are of particular interest due to their incredible chemical variety and the advantage of tuning the properties and functionality of their assemblies. First, the architectures of micro- and nanoscale polymer assemblies are introduced and then their usage as building blocks is elaborated upon. Different membrane-bound and membrane-less compartments and supramolecular structures and how they combine into advanced synthetic cells are presented. Then, the functional aspects are explored, addressing how artificial organelles in giant compartments mimic cellular processes. Finally, how artificial cells communicate with their surrounding and each other such as to adapt to an ever-changing environment and achieve collective behavior as a steppingstone toward artificial tissues, is taken a look at. Engineering artificial cells with highly controllable and programmable features open new avenues for the development of sophisticated multifunctional systems.

Self-Assembly and In Situ Quaternization of Triblock Bottlebrush Block Copolymers via Organized Spontaneous Emulsification for Effective Loading of DNA

Microspheres bearing large pores are useful in the capture and separation of biomolecules. However, pore size is typically poorly controlled, leading to disordered porous structures with limited performances. Herein, ordered porous spheres with a layer of cations on the internal surface of the nanopores are facilely fabricated in a single step for effective loading of DNA bearing negative charges. Triblock bottlebrush copolymers (BBCPs), (polynorbornene-g-polystyrene)-b-(polynorbornene-g-polyethylene oxide)-b-(polynorbornene-g-bromoethane) (PNPS-b-PNPEO-b-PNBr), are designed and synthesized for fabrication of the positively charged porous spheres through self-assembly and in situ quaternization during an organized spontaneous emulsification (OSE) process. Pore diameter as well as charge density increase with the increase of PNBr content, resulting in a significant increase of loading density from 4.79 to 22.5 ng µg-1 within the spheres. This work provides a general strategy for efficient loading and encapsulation of DNA, which may be extended to a variety of different areas for different real applications.

Advances of Nanotechnology in the Diagnosis and Treatment of Hepatocellular Carcinoma

Nanotechnology has emerged as a promising technology in the field of hepatocellular carcinoma (HCC), specifically in the implementation of diagnosis and treatment strategies. Nanotechnology-based approaches, such as nanoparticle-based contrast agents and nanoscale imaging techniques, have shown great potential for enhancing the sensitivity and specificity of HCC detection. These approaches provide high-resolution imaging and allow for the detection of molecular markers and alterations in cellular morphology associated with HCC. In terms of treatment, nanotechnology has revolutionized HCC therapy by enabling targeted drug delivery, enhancing therapeutic efficacy, and minimizing off-target effects. Nanoparticle-based drug carriers can be functionalized with ligands specific to HCC cells, allowing for selective accumulation of therapeutic agents at the tumor site. Furthermore, nanotechnology can facilitate combination therapy by co-encapsulating multiple drugs within a single nanoparticle, allowing for synergistic effects and overcoming drug resistance. This review aims to provide an overview of recent advances in nanotechnology-based approaches for the diagnosis and treatment of HCC. Further research is needed to optimize the design and functionality of nanoparticles, improve their biocompatibility and stability, and evaluate their long-term safety and efficacy. Nonetheless, the integration of nanotechnology in HCC management holds great promise and may lead to improved patient outcomes in the future.

CL4-modified exosomes deliver lncRNA DARS-AS1 siRNA to suppress triple-negative breast cancer progression and attenuate doxorubicin resistance by inhibiting autophagy

Triple-negative breast cancer (TNBC) is a fatal disease. Drug resistance and the lack of effective drugs are the leading causes of death in patients with TNBC. Recently, long non-coding RNAs have been proven to be effective drug design targets owing to their high tissue specificity; however, an effective drug delivery system is necessary for their clinical application. In this study, we constructed a novel nanodrug delivery system based on the epidermal growth factor receptor (EGFR)-targeted aptamer CL4-modified exosomes (EXOs-CL4) for the targeted delivery of aspartyl-tRNA synthetase-antisense RNA 1 (DARS-AS1) small interfering RNA (siRNA) and doxorubicin (DOX) to TNBC cells in vitro and in vivo. This delivery system exerted potent anti-proliferation, anti-migration, and pro-apoptotic effects on TNBC cells. Silencing DARS-AS1 increased the sensitivity of TNBC cells to DOX by suppressing the transforming growth factor-β (TGF-β)/Smad3 signaling pathway-induced autophagy, thereby enhancing the synergetic antitumor effects. Collectively, our findings revealed that EXOs-CL4-mediated delivery of DARS-AS1 siRNA can be used as a new treatment strategy for DOX-resistant TNBC. Moreover, EXOs-CL4 can be used as effective drug delivery systems for targeted TNBC therapy.

Bladder microenvironment actuated proteomotors with ammonia amplification for enhanced cancer treatment

Enzyme-driven micro/nanomotors consuming in situ chemical fuels have attracted lots of attention for biomedical applications. However, motor systems composed by organism-derived organics that maximize the therapeutic efficacy of enzymatic products remain challenging. Herein, swimming proteomotors based on biocompatible urease and human serum albumin are constructed for enhanced antitumor therapy via active motion and ammonia amplification. By decomposing urea into carbon dioxide and ammonia, the designed proteomotors are endowed with self-propulsive capability, which leads to improved internalization and enhanced penetration in vitro. As a glutamine synthetase inhibitor, the loaded l-methionine sulfoximine further prevents the conversion of toxic ammonia into non-toxic glutamine in both tumor and stromal cells, resulting in local ammonia amplification. After intravesical instillation, the proteomotors achieve longer bladder retention and thus significantly inhibit the growth of orthotopic bladder tumor in vivo without adverse effects. We envision that the as-developed swimming proteomotors with amplification of the product toxicity may be a potential platform for active cancer treatment.

Glycopolymers Mediate Suicide Gene Therapy in ASGPR-Expressing Hepatocellular Carcinoma Cells in Tandem with Docetaxel

Cationic glycopolymers stand out as gene delivery nanosystems due to their inherent biocompatibility and high binding affinity to the asialoglycoprotein receptor (ASGPR), a target receptor overexpressed in hepatocellular carcinoma (HCC) cells. However, their synthesis procedure remains laborious and complex, with problems of solubilization and the need for protection/deprotection steps. Here, a mini-library of well-defined poly(2-aminoethyl methacrylate hydrochloride-co-poly(2-lactobionamidoethyl methacrylate) (PAMA-co-PLAMA) glycopolymers was synthesized by activators regenerated by electron transfer (ARGET) ATRP to develop an efficient gene delivery nanosystem. The glycoplexes generated had suitable physicochemical properties and showed high ASGPR specificity and high transfection efficiency. Moreover, the HSV-TK/GCV suicide gene therapy strategy, mediated by PAMA₁₄₄-co-PLAMA₁₉-based nanocarriers, resulted in high antitumor activity in 2D and 3D culture models of HCC, which was significantly enhanced by the combination with small amounts of docetaxel. Overall, our results demonstrated the potential of primary-amine polymethacrylate-containing-glycopolymers as HCC-targeted suicide gene delivery nanosystems and highlight the importance of combined strategies for HCC treatment.

Recent progress and applications of poly(beta amino esters)-based biomaterials

Poly(beta-amino esters, PBAEs) are a promising class of cationic polymers synthesized from diacrylates and amines via Michael addition. Recently, PBAEs have been widely developed for drug delivery, immunotherapy, gene therapy, antibacterial, tissue engineering and other applications due to their convenient synthesis, good bio-compatibility and degradation properties. Herein, we mainly summarize the recent progress in the PBAEs synthesis and their applications. The amine groups of PBAEs could be protonated in low pH environment, exhibiting proton sponge and pH-sensitive abilities. Furthermore, the positive PBAEs can interact with negative genes via electrostatic interactions for efficient delivery of nucleic acids. Moreover, positive PBAEs could also directly kill bacteria by disrupting their membranes at high doses. Finally, PBAEs can augment the immune responses, and improve the bioactivity of hydrogels in tissue engineering.

Non-Viral Gene Delivery to Hepatocellular Carcinoma via Intra-Arterial Injection

Purpose

Hepatocellular carcinoma (HCC) has limited treatment options, and modest survival after systemic chemotherapy or procedures such as transarterial chemoembolization (TACE). There is therefore a need to develop targeted therapies to address HCC. Gene therapies hold immense promise in treating a variety of diseases, including HCC, though delivery remains a critical hurdle. This study investigated a new approach of local delivery of polymeric nanoparticles (NPs) via intra-arterial injection for targeted local gene delivery to HCC tumors in an orthotopic rat liver tumor model.

Methods

Poly(beta-amino ester) (PBAE) nanoparticles were formulated and assessed for GFP transfection in N1-S1 rat HCC cells in vitro. Optimized PBAE NPs were next administered to rats via intra-arterial injection with and without orthotopic HCC tumors, and both biodistribution and transfection were assessed.

Results

In vitro transfection of PBAE NPs led to >50% transfected cells in adherent and suspension culture at a variety of doses and weight ratios. Administration of NPs via intra-arterial or intravenous injection demonstrated no transfection of healthy liver, while intra-arterial NP injection led to transfection of tumors in an orthotopic rat HCC model.

Conclusion

Hepatic artery injection is a promising delivery approach for PBAE NPs and demonstrates increased targeted transfection of HCC tumors compared to intravenous administration, and offers a potential alternative to standard chemotherapies and TACE. This work demonstrates proof of concept for administration of polymeric PBAE nanoparticles via intra-arterial injection for gene delivery in rats.