Lipid Nanoparticle Technology for Clinical Translation of siRNA Therapeutics

Nanocarrier-mediated siRNA delivery: a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

Traumatic brain injury and Alzheimer's disease share pathological similarities, including neuronal loss, amyloid-β deposition, tau hyperphosphorylation, blood-brain barrier dysfunction, neuroinflammation, and cognitive deficits. Furthermore, traumatic brain injury can exacerbate Alzheimer's disease-like pathologies, potentially leading to the development of Alzheimer's disease. Nanocarriers offer a potential solution by facilitating the delivery of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease. Unlike traditional approaches to neuroregeneration, this is a molecular-targeted strategy, thus avoiding non-specific drug actions. This review focuses on the use of nanocarrier systems for the efficient and precise delivery of siRNAs, discussing the advantages, challenges, and future directions. In principle, siRNAs have the potential to target all genes and non-targetable proteins, holding significant promise for treating various diseases. Among the various therapeutic approaches currently available for neurological diseases, siRNA gene silencing can precisely "turn off" the expression of any gene at the genetic level, thus radically inhibiting disease progression; however, a significant challenge lies in delivering siRNAs across the blood-brain barrier. Nanoparticles have received increasing attention as an innovative drug delivery tool for the treatment of brain diseases. They are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier, targeted drug delivery, enhanced drug stability, and multifunctional therapy. The use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective approach. Although this strategy is still in the preclinical exploration stage, it is expected to achieve clinical translation in the future, creating a new field of molecular targeted therapy and precision medicine for the treatment of Alzheimer's disease associated with traumatic brain injury.

siRNA-based delivery systems: Technologies, carriers, applications, and approved products

Ribonucleic acid (RNA) therapeutics are a novel category of therapeutic agents that use different types of RNAs to regulate genes and modulate protein synthesis to treat a wide range of diseases. The main advantages of RNA therapeutics over conventional small molecule drugs would be the potential to target undruggable sites, ease of production and faster development process, and longer duration of action. Various types of RNA therapeutics including antisense oligonucleotides (ASO), RNA interference (RNAi), small interfering RNA (siRNA), microRNA (miRNA), and messenger RNA (mRNA), have been developed and used for various clinical applications, especially for gene and vaccine delivery purposes. This review is focused on various therapeutic applications of RNA-based delivery systems and then siRNA technologies are discussed in more detail. Next, the FDA-approved siRNA therapeutics and those are in clinical trials are listed and summarized. Then, various viral and non-viral vectors used for RNA delivery purposes are discussed. Finally, clinical applications of siRNA therapeutics are reviewed in detail.

METTL14 Promotes Ischemic Stroke-induced Brain Injury by Stabilizing HDAC3 Expression in an m6A-IGF2BP3 Mechanism

N6-methyladenosine (m6A) modification is the most abundant post-transcriptional modification of mRNAs and has been identified to play critical roles in ischemic stroke (IS). Herein, this study aimed to investigate the function and mechanism of Methyltransferase-like 14 (METTL14) methylase in cerebral IS. Murine BV-2 microglial cell OGD/R models and rat middle cerebral artery occlusion (MCAO) models were established to mimic IS-induced neuronal damage in vitro and brain injury in vivo. Levels of METTL14, Histone Deacetylase 3 (HDAC3) and cGAS-STING axis-related proteins were detected using qRT-PCR or western blotting. Cell proliferation and inflammation were assessed by CCK-8 assay, EdU assay and ELISA. Flow cytometry detected microglia polarization. Cell pyroptosis was analyzed by detecting related-protein markers by western blotting. The m6A modification was determined by methylated RNA immunoprecipitation assay. Brain injury was analyzed by evaluating infarct volume and neurologic score. METTL14 levels were higher in OGD/R-induced microglial cells, primary microglia and infarct brain tissues of rat MCAO models. Functionally, METTL14 silencing reversed OGD/R-induced proliferation inhibition, inflammation and pyroptosis in microglial cells and primary microglia in vitro, and ameliorated cerebral ischemic injury in rat MCAO models. Mechanistically, METTL14 induced HDAC3 m6A modification in an IGF2BP3-dependent manner, and could activate cGAS-STING pathway through HDAC3. Moreover, HDAC3 overexpression reversed the neuroprotective effects of METTL14 silencing. METTL14 silencing reversed ischemic stroke-induced brain injury by inducing HDAC3 m6A modification in an IGF2BP3-dependent mechanism, recommending a novel insight for ameliorating cerebral ischemic stroke.

Targeted delivery of circPDHK1 siRNA via aptamer functionalized lipid nanoparticles inhibits ccRCC growth and migration

Clear Cell Renal Cell Carcinoma (ccRCC) is a common malignancy with high mortality in China, requiring innovative treatments. Recent advances in nucleic acid drugs, notably small interfering RNAs (siRNAs), show promise for therapeutic applications. Circular RNAs (circRNAs) play vital roles in cancer progression, and our previous work has identified that upregulated circPDHK1 can promote ccRCC growth and migration. However, the delivery strategies of si circPDHK1 targeting the circPDHK1 against ccRCC are not thoroughly investigated. Here, we developed a novel nucleic acid drug delivery system, AS1411/LNP-si circPDHK1, utilizing lipid nanoparticles (LNPs) encapsulated with siRNA targeting circPDHK1 and modified with the AS1411 aptamer for precise tumor targeting. In vitro and in vivo studies demonstrated that AS1411/LNP-si circPDHK1 efficiently delivered si circPDHK1 to ccRCC cells, resulting in a significant reduction in circPDHK1 expression. This delivery system exhibited superior tumor-targeting capabilities and prolonged circulation time compared with non-targeted formulations. Notably, AS1411/LNP-si circPDHK1 successfully inhibited the phosphorylation of the mTOR-AKT pathway, suppressed the proliferation and migration of ccRCC cells, and exhibited minimal side effects in vital organs. Taken together, the aptamer-guided LNP loaded siRNA targeting circPDHK1 (AS1411/LNP-si circPDHK1) displays great potential for ccRCC therapy.

One-Component Ionizable Amphiphilic Janus Dendrimers for Targeted mRNA Delivery

mRNA nanomedicine represents a new generation of therapeutics. However, how to deliver mRNA to the desired organs and cells effectively remains challenging. Common mRNA delivery vectors include viral and nonviral types such as four-component lipid nanoparticles (LNPs), polymer-based nanoparticles, lipid-polymer hybrid nanoparticles, and so on. One-component ionizable amphiphilic Janus dendrimers (IAJDs), are an emerging type of mRNA delivery vehicle displaying good stability and high delivery efficiency. In this review, we comprehensively present the design, synthesis, and mRNA delivery properties of IAJDs, with particular focus on the relationship between their molecular structures and organ targeted delivery properties. Other representative types of dendrimers for RNA delivery are also reviewed. Overall, this review summarizes the recent research progress on IAJDs systematically, aiming to guide the development of more efficient mRNA delivery platforms and next-generation mRNA nanomedicines.

M2 macrophage-targeted metal-polyphenol networks (MPNs) for OPN siRNA delivery and idiopathic pulmonary fibrosis therapy

Idiopathic pulmonary fibrosis (IPF) exhibits extremely high mortality rates. Targeted therapy, which utilizes specific drugs or other substances to identify and attack specific molecular targets in the lesion, holds promise as a potent means of treating IPF. M2 macrophages have been shown to express high levels of osteopontin (OPN) early in the onset of IPF and sustain this high expression to promote the progression of IPF. Intervention in OPN expression can effectively impede the development of fibrosis. While the technology for targeting proteins with siRNA has become increasingly mature, the targeted delivery of siRNA to resident M2 macrophages in the lungs remains challenging. In this study, we developed an engineered self-assembling OPN siRNA carrier complex based on a metal-polyphenol network (luteolin-Zr) and PEG conjugated with an M2 macrophage-targeting peptide (Pery-PEG-M2), termed siOPN@LuZ-M2, for the treatment of pulmonary fibrosis. Consequently, significant therapeutic effects were observed in both bleomycin-induced pulmonary fibrosis mouse models and human precision-cut lung slices (hPCLS) models. Importantly, luteolin, which is slowly released from siOPN@LuZ-M2 within cells, can gradually accumulate in fibrotic lung tissue, exerting an anti-inflammatory effect and further enhancing the treatment of IPF. It is worth mentioning that siOPN@LuZ-M2 can be labeled with 89Zr, allowing for the detection of its in vivo distribution and metabolic behavior via PET-CT. This study presents a promising new image-guided molecular targeting strategy for the treatment of fibrosis.

Characterization of lipid nanoparticles using macro mass photometry: Insights into size and mass

BACKGROUND

Lipid nanoparticles (LNPs) have become an important delivery system for nucleic acids, as applied in the first RNAi drug and two COVID-19 mRNA vaccines approved by the FDA. Despite advantages of their high cargo capacity, low immunogenicity allowing for redosing, scalability and low-cost manufacturing, challenges such as liver accumulation and difficulties in quality control persist for LNPs development. Conjugation of antibodies or antibody fragments onto LNPs holds promise in achieving precise targeting and higher stability of the targeting moieties on LNP surfaces. However, quality control of such multiple-component products poses additional challenges compared to LNP alone. LNP size and mass are critical quality attributes which play important roles in determining LNPs' nucleic acid cargo loading, antibody conjugation level, biodistribution, targeting capability, and overall efficacy.

RESULTS

Macro mass photometry (MMP), a single-molecule technique, enabled orthogonal characterization of LNPs by incorporating contrast analysis as a proxy for particle mass and combining it with size measurement. This approach thus improves the definition of LNP species within heterogeneous systems. Using MMP, this study revealed the effects of PEG-lipid concentration, mRNA encapsulation, and antibody conjugation on LNP size and mass. Additionally, the study demonstrated the MMP's utility in monitoring LNPs under various stress conditions, including high pH, low pH, oxidation, freeze-thaw cycles, and agitation.

SIGNIFICANCE

This study represents the first use of mass photometry for LNP analysis, simultaneously characterizing the mass and size of LNPs. It highlights the potential of MMP as a valuable orthogonal tool for LNP characterization and supports LNP formulation development.

Local delivery of siRNA using lipid-based nanocarriers with ROS-scavenging ability for accelerated chronic wound healing in diabetes

Diabetic wound healing poses a significant clinical challenge with limited therapeutic efficacy due to uncontrolled reactive oxygen species (ROS), inflammatory responses, and extracellular matrix (ECM) degradation caused by abnormal macrophage activity in the wound microenvironment. To address these concerns, we propose a novel formulation that combines Tempo-conjugated lipid with the commercially cationic lipid DOTAP to expedite diabetic wound healing through targeted siRNA delivery (cLpT@siRNA) and restoration of the wound microenvironment. The developed cLpT@siRNA nanocomplexes effectively scavenge excessive ROS levels, facilitate polarization of proinflammatory M1 macrophages towards an anti-inflammatory M2 phenotype, and suppress MMP9 gene expression in macrophages. In the ICR mouse model of diabetic wounds, cLpT@siRNA nanocomplexes significantly accelerate wound healing, promoting neovascularization and collagen deposition. Overall, the cLpT@siRNA nanocomplexes based on antioxidant and cationic lipids provide a promising strategy for delivering siRNA in diabetic wound treatment and hold great potential for clinical translation.

Lipid nanoparticle (LNP) mediated mRNA delivery in neurodegenerative diseases

Neurodegenerative diseases (NDD) are characterized by the progressive loss of neurons and the impairment of cellular functions. Messenger RNA (mRNA) has emerged as a promising therapy for treating NDD, as it can encode missing or dysfunctional proteins and anti-inflammatory cytokines or neuroprotective proteins to halt the progression of these diseases. However, effective mRNA delivery to the central nervous system (CNS) remains a significant challenge due to the limited penetration of the blood-brain barrier (BBB). Lipid nanoparticles (LNPs) offer an efficient solution by encapsulating and protecting mRNA, facilitating transfection and intracellular delivery. This review discusses the pathophysiological mechanisms of neurological disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS), Huntington's disease (HD), ischemic stroke, spinal cord injury, and Friedreich's ataxia. Additionally, it explores the potential of LNP-mediated mRNA delivery as a therapeutic strategy for these diseases. Various approaches to overcoming BBB-related challenges and enhancing the delivery and efficacy of mRNA-LNPs are discussed, including non-invasive methods with strong potential for clinical translation. With advancements in artificial intelligence (AI)-guided mRNA and LNP design, targeted delivery, gene editing, and CAR-T cell therapy, mRNA-LNPs could significantly transform the treatment landscape for NDD, paving the way for future clinical applications.

Delivery of Itgb1-siRNA by triptolide-modified and anti-Flt1 peptide-guided ionizable cationic LNPs for targeted therapy of corneal neovascularization

Corneal neovascularization (CoNV) is a leading cause of visual impairment worldwide. However, CoNV remains challenging to cure clinically because of the limitations of current drugs. New and more effective therapeutic formulations for CoNV treatment are therefore urgently needed. Antisense oligonucleotide drugs hold great promise for the treatment of neovascular diseases, and ionizable cationic lipid nanoparticles (icLNPs) have shown excellent performance for nucleic acid delivery, with high encapsulation, good cellular uptake, and effective endosomal escape. In the present study, we identified integrin β1 (Itgb1) as a key gene involved in angiogenesis and revealed the significant upregulation of Flt1 in vascular endothelial cells and pericytes in CoNV using single-cell sequencing. Itgb1 knockdown significantly inhibited the proliferation and migration of vascular endothelial cells and CoNV in mice. Based on these findings, we developed Itgb1-small interfering RNA (siRNA)-loaded icLNPs, and conjugated anti-Flt1 peptide to their surface to improve CoNV targeting. Furthermore, because lipid nanoparticles reportedly trigger immune responses by upregulating pro-inflammatory cytokine expression, which may promote neovascularization, we modified triptolide (a compound with anti-inflammatory properties) into the icLNPs. The triptolide-modified, anti-Flt1 peptide-conjugated, and Itgb1-siRNA-loaded icLNPs (Itgb1-siRNA@TPL) effectively inhibited the proliferation and migration of vascular endothelial cells in vitro and CoNV in mice after eye drop administration. These effects occurred via downregulation of the PI3K/AKT and NF-κB signaling pathways. Finally, the biosafety of Itgb1-siRNA@TPL was tested, and the results revealed that it was not toxic to the cornea or major organs and had no impact on corneal epithelial healing. In conclusion, Itgb1-siRNA@TPL represent a novel, noninvasive, and effective approach for the treatment of CoNV.

Inhalable myofibroblast targeting nanoparticles for synergistic treatment of pulmonary fibrosis

Pulmonary fibrosis (PF) is a life-threatening interstitial lung disease, characterized by excessive fibroblast activation and collagen deposition, leading to progressive pulmonary function decline and limited therapeutic efficacy. Here, the inhalable, myofibroblast-targeted, and pH-responsive liposomes (FL-NI) were developed for effective codelivery of nintedanib, a mainstream antifibrotic drug in clinic, and siIL11, a small interfering RNA that silences the key profibrosis cytokine IL-11. Notably, FL-NI achieved a 117.8% increase in pulmonary drug delivery by noninvasive inhalation and a 71.5% increase in delivery specifically to fibroblast activation protein-positive myofibroblasts while reducing nonspecific immune cell and epithelial uptake by 29.8 and 55.8%, respectively. The accurate inhalation codelivery of nintedanib and siIL11 into myofibroblasts achieved synergistic effects, effectively enhanced myofibroblast deactivation, reduced pathological collagen deposition by 50.8%, and promoted epithelial tissue repair. FL-NI remodeled the aberrant immune microenvironment without inducing systemic toxicities. Therefore, this work demonstrated the notable potential for this pluripotent strategy for improving PF outcomes and its promising clinical translation.

Prediction and control of the particle size of polyethylene glycol-free lipid nanoparticles using a design of experiment

Rigorous control of the properties of lipid nanoparticles (LNPs) such as the particle size, polydispersity index (PdI), ζ-potential, and encapsulation efficiency of small interfering RNA (siRNA) with good reproducibility is important for LNP-based siRNA delivery. In this study, polyethylene glycol (PEG)-free LNPs containing a dioleoylglycerophosphate-diethylenediamine conjugate (DOP-DEDA), which is a pH-responsive lipid derivative, were prepared by using a microfluidic technology to construct a predictive model for particle size control using the design of experiment (DoE). PEG-free DOP-DEDA-based LNPs (DEDA LNPs) encapsulating siRNA, which were prepared by using a microfluidic technology, formed uniform particles and triggered effective gene silencing. The effects of the preparation conditions such as the total flow rate, lipid concentration, and lipid solution ratio on the LNP properties were investigated, and results indicated that the lipid solution ratio is the most important parameter to control the particle size and PdI of DEDA LNPs. Conversely, the ζ-potential and siRNA encapsulation efficiency of DEDA LNPs were not affected by the preparation conditions. The predictive model constructed using the DoE data showed that the particle size of the prepared DEDA LNPs was consistent with that predicted. Therefore, our approach using the DoE will contribute to the rigorous prediction and control of the particle size of PEG-free LNPs for nucleic acid delivery.

mRNA-based vaccines and therapies - a revolutionary approach for conquering fast-spreading infections and other clinical applications: a review

Since the beginning of the COVID-19 pandemic, the development of messenger RNA (mRNA) vaccines has made significant progress in the pharmaceutical industry. The two COVID-19 mRNA vaccines from Moderna and Pfizer/BioNTech have been approved for marketing and have made significant contributions to preventing the spread of SARS-CoV-2. In addition, mRNA therapy has brought hope to some diseases that do not have specific treatment methods or are difficult to treat, such as the Zika virus and influenza virus infections, as well as the prevention and treatment of tumors. With the rapid development of in vitro transcription (IVT) technology, delivery systems, and adjuvants, mRNA therapy has also been applied to hereditary diseases such as Fabry's disease. This article reviews the recent development of mRNA vaccines for structural modification, treatment and prevention of different diseases; delivery carriers and adjuvants; and routes of administration to promote the clinical application of mRNA therapies.

Cytidinyl/Cationic Lipid Encapsulating Insulin-Like Growth Factor 1 Receptor siRNA for Hepatocellular Carcinoma Therapy

Hepatocellular carcinoma (HCC) is the most prevalent form of invasive liver cancer, representing over 90% of all liver cancer cases. Currently, there is a lack of targeted therapy for HCC. Insulin-like growth factor 1 receptor (IGF1R) is abnormally expressed in HCC, leading to the malignant proliferation and contributing to the antiapoptosis mechanisms in tumor cells. In this study, small interfering RNAs targeting IGF1R mRNA (siIGF1Rs) have been designed. Additionally, a full 2'-F/2'-OMe modification with partial phosphorothioation was applied to improve the biological properties of these siIGF1Rs. Based on previous research, stable lipid complexes with uniform particle sizes were constructed using cytidinyl lipid DNCA/cationic lipid CLD (Mix) supplemented with DSPE-PEG (siIGF1R/Mix/PEG). The complexes were formed through hydrogen-bonding, π-π stacking, and electrostatic interactions. The siIGF1R/Mix/PEG complex entered the cytoplasm and nucleus of HCC cells, reduced IGF1R mRNA and pre-mRNA levels by over 95% and 50% respectively, further arrested the cell cycle in the S phase, and promoted cell apoptosis. Importantly, siIGF1R/Mix/PEG (0.8 mg/kg, i.v.) selectively accumulated in the tumor, significantly inhibiting tumor growth by 91.31% compared to the naked siRNA group, with slower release and a more prolonged effect.

Evolution of Lipo-Xenopeptide Carriers for siRNA Delivery: Interplay of Stabilizing Subunits

Although small interfering RNA (siRNA) holds immense promise for treating genetic diseases and cancers, its clinical application is constrained by instability, cellular uptake barriers, and inefficient cytosolic delivery, underscoring the need for effective delivery systems. Therefore, this study focuses on screening novel T-shaped lipo-xenopeptide (XP) nanocarriers for siRNA polyplex formulation, integrating two single succinoyl-tetraethylene pentamine (Stp) units for electrostatic interaction and tyrosine tripeptides (Y3) for aromatic stabilization, along with structural modifications such as the addition of histidine (H) with or without terminal cysteines (C), and the incorporation of various fatty acids (FAs). A systematic evaluation of siRNA binding, nanoparticle stability, and gene silencing efficiency in multiple cell lines illustrated that the novel Stp1-HC lipo-XPs carriers outperform their Stp2-HC analogs, despite having fewer cationizable Stp units. This advantage stems from increased fatty acid, Y3, and C density, which compensates for reduced electrostatic interactions. The presence of H in combination with unsaturated FAs significantly improved the functional siRNA delivery. Our findings highlight the complex interplay of electrostatic, hydrophobic, covalent, hydrogen-bonded, and aromatic interactions to achieve efficient siRNA delivery, which is best-balanced in the oleic acid-containing Stp1-HC/OleA lipo-XP, exceeding the previously best standard carrier Stp2-HC/OleA in efficiency.

Peptide-Modified Lipid Nanoparticles Boost the Antitumor Efficacy of RNA Therapeutics

RNA therapeutics offer a promising approach to cancer treatment by precisely regulating cancer-related genes. While lipid nanoparticles (LNPs) are currently the most advanced nonviral clinically approved vectors for RNA therapeutics, their antitumor efficacy is limited by their unspecific hepatic accumulation after systemic administration. Thus, there is an urgent need to enhance the delivery efficiency of LNPs to target tumor-residing tissues. Here, we conjugated the cluster of differentiation 44 (CD44)-specific targeting peptide A6 (KPSSPPEE) to the cholesterol of LNPs via PEG, named AKPC-LNP, enabling specific tumor delivery. This modification significantly improved delivery to breast cancer cells both in vitro and in vivo, as shown by flow cytometry and confocal microscopy. We further used AKPC-siYT to codeliver siRNAs targeting the transcriptional coactivators YAP and TAZ, achieving potent gene silencing and increased cell death in both 2D cultures and 3D tumor spheroids, outperforming unmodified LNPs. In a breast tumor cell xenografted zebrafish model, systemically administered AKPC-siYT induced robust silencing of YAP/TAZ and downstream genes and significantly enhanced tumor suppression compared to unmodified LNPs. Additionally, AKPC-siYT effectively reduced proliferation in prostate cancer organoids and tumor growth in a patient-derived xenograft (PDX) model. Overall, we developed highly efficient AKPC-LNPs carrying RNA therapeutics for targeted cancer therapy.

Placental targeted drug delivery: a review of recent progress

The placenta plays a crucial role in mediating nutrient and gas exchange between the mother and fetus during pregnancy. Targeting therapeutic agents to the placenta presents significant opportunities for treating placental disorders and enhancing fetal outcomes. However, the unique structural complexity and selective permeability of the placenta pose substantial challenges for effective drug delivery. This review provides a comprehensive overview of current strategies for placental targeting, including lipid nanoparticle (LNP) delivery systems, targeted peptide modifications, specific antibody targeting of placental receptors, and the use of viral vectors. We critically analyze the advantages and limitations of each approach, emphasizing recent advancements in enhancing targeting specificity and delivery efficiency. By consolidating the latest research developments, this review aims to foster further innovation in placental drug delivery methods and contribute significantly to the advancement of therapeutic strategies for placental disorders, ultimately improving outcomes for both mother and fetus.

Familial chylomicronemia syndrome and treatments to target hepatic APOC3 mRNA

Familial chylomicronemia syndrome (FCS) is a rare, recessive monogenic disorder characterized by severely elevated plasma triglyceride (TG) levels due to absent or markedly impaired lipoprotein lipase activity, leading to a greatly increased risk of acute pancreatitis. Naturally occurring very low levels of apoC-III are associated with low TG levels; thus, apoC-III is a target for TG lowering, and therapies have been developed to reduce apoC-III. Strategies to inhibit hepatic apoC-III synthesis include antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs). In the last decade, technologies have been developed to enhance hepatic delivery of these potential therapeutic agents by conjugation of the ligand triantennary N-acetyl galactosamine to ASO and siRNA for receptor-mediated uptake by hepatocytes, where apoC-III is predominantly expressed. Enhanced delivery of these pharmacological agents to the target tissue has been found to support lower and/or less frequent dosing with consequent lower total systemic exposure. One antisense agent, the ASO olezarsen, is now approved by the US Food and Drug Administration (FDA) as an adjunct to diet to lower triglycerides in adults with FCS, and the other, the siRNA plozasiran, is in late-stage clinical development. Both agents have shown effectiveness in reducing both apoC-III and TG levels across several study populations. Reduced TG, lower rates of acute pancreatitis events, and similar proportions of adverse events in placebo and treated patients were recently demonstrated in placebo-controlled phase 3 trials of patients with FCS treated with olezarsen in Balance and with plozasiran in PALISADE. This review discusses causes and consequences of FCS and the rationale and progress made in developing APOC3 RNA-targeted therapeutics for the treatment of FCS.

Overcoming matrix barriers for enhanced immune infiltration using siRNA-coated metal-organic frameworks

The extracellular matrix (ECM) of solid tumor constitutes a formidable physical barrier that impedes immune cell infiltration, contributing to immunotherapy resistance. Breast cancer, particularly triple-negative breast cancer (TNBC), is characterized by a collagen-rich tumor microenvironment, which is associated with T cell exclusion and poor therapeutic outcomes. Discoidin domain receptor 2 (DDR2) and integrins, key ECM regulatory receptors on cancer cells, play pivotal role in maintaining this barrier. In this study, we developed a dual-receptor-targeted strategy using metal-organic frameworks (MOFs) to deliver DDR2-specific siRNA (siDDR2) and ITGAV-specific siRNA (siITGAV) to disrupt the ECM barrier. siDDR2 modulates immune infiltration by regulating collagen-cell interactions, while siITGAV suppresses TGF-β1 activation. The MOF@siDDR2+siITGAV complex significantly reduced collagen deposition, enhanced CD8+ T cell infiltration, and downregulated programmed cell death ligand 1 (PD-L1) expression in TNBC. Consequently, this approach markedly inhibited tumor growth. Our findings demonstrate that dual-receptor-targeted MOF-based nanocarriers (MOF@siDDR2+siITGAV) can effectively reprogram the tumor ECM to enhance immune cell access, offering a promising prospect for synergistic cancer immunotherapy. STATEMENT OF SIGNIFICANCE: A dual-receptor-targeted MOF nanocarrier is developed to improve immune accessibility in tumors. Concurrent blockade of DDR2 and ITGAV effectively decreases collagen deposition, increases CD8+ T cell infiltration, and suppresses PD-L1 expression. Modulating the mechanical properties of the extracellular matrix (ECM) to enhance immune accessibility offers an innovative strategy for cancer treatment.

Lipid-siRNA Organization Modulates the Intracellular Dynamics of Lipid Nanoparticles

Lipid nanoparticles (LNPs) are widely used for delivering therapeutic nucleic acids, yet the relationship between their internal structure and intracellular behavior, particularly before RNA release, remains unclear. Here, we elucidate how lipid-siRNA organization within LNPs can modulate their intracellular delivery dynamics. We use cryo-electron microscopy and photochemical assays to reveal that increased siRNA loading can reduce helper lipids' distribution to the LNP surface, while siRNA consistently localizes near the surface. These alterations in lipid-siRNA organization affect LNP membrane fluidity, enhancing LNP fusion with cellular membranes and promoting cytosolic siRNA delivery, primarily via macropinocytosis. Using photosensitive lipids and live cell imaging, we demonstrate that lipid-siRNA organization regulates LNP responsiveness to external stimuli, significantly affecting siRNA endosomal escape efficiency upon light activation. We further confirm this observation using convex lens-induced confinement microscopy and single-particle imaging. Overall, our findings provide critical insights into how lipid-siRNA organization shapes LNP intracellular dynamics, offering rational design principles for optimizing LNP-based RNA therapeutics.

Lipid Nanoparticles for mRNA Delivery in Cancer Immunotherapy

Cancer immunotherapy is poised to be one of the major modalities for cancer treatment. Messenger RNA (mRNA) has emerged as a versatile and promising platform for the development of effective cancer immunotherapy. Delivery systems for mRNA therapeutics are pivotal for their optimal therapeutic efficacy and minimal adverse side effects. Lipid nanoparticles (LNPs) have demonstrated a great success for mRNA delivery. Numerous LNPs have been designed and optimized to enhance mRNA stability, facilitate transfection, and ensure intracellular delivery for subsequent processing. Nevertheless, challenges remain to, for example, improve the efficiency of endosomal escape and passive targeting. This review highlights key advancements in the development of mRNA LNPs for cancer immunotherapy. We delve into the design of LNPs for mRNA delivery, encompassing the chemical structures, characterization, and structure-activity relationships (SAR) of LNP compositions. We discuss the key factors influencing the transfection efficiency, passive targeting, and tropism of mRNA-loaded LNPs. We also review the preclinical and clinical applications of mRNA LNPs in cancer immunotherapy. This review can enhance our understanding in the design and application of LNPs for mRNA delivery in cancer immunotherapy.

Shielding siRNA by peptide-based nanofibers: An efficient approach for turning off EGFR gene in breast cancer

Peptide-based self-assembled nanosystems show great promise as non-viral gene and siRNA delivery vectors. In the current study, we designed and functionalized nanofibers for the delivery of siRNA, targeting and silencing EGFR gene overexpressed in triple-negative breast cancer. The nanofiber-mediated siRNA delivery was characterized in terms of zeta potential, morphology, and structural stability by circular dichroism spectroscopy. In cytotoxicity studies, nanofibers presented high biocompatibility showing a negligible effect on cell viability both on healthy and cancer cell lines. The binding between nanofibers and EGFR-siRNA was investigated and ascertained by performing different biophysical studies. The complex siRNA:NF was stable over time, under fetal bovine serum, temperature and ionic strength effects. Moreover, nanofibers effectiveness in stabilizing and delivering an ad hoc selected siRNA for EGFR gene expression silencing was verified in a preclinical model of triple-negative breast cancer. Specifically, a significant gene knockdown was obtained with the complex siRNA:NF, that is comparable with the effect obtained by lipofectamine/siRNA transfection. This effective gene silencing derived from the successful internalization of nanofibers by cancer cells as observed by confocal microscopy. These results suggested that this peptide-based nanofiber could be an effective and safe systemic siRNA delivery system for application in biomedical areas.

Circular RNAs as key regulators in cancer hallmarks: New progress and therapeutic opportunities

Circular RNAs (circRNAs) have emerged as critical regulators in cancer biology, contributing to various cancer hallmarks, including cell proliferation, apoptosis, metastasis, and drug resistance. Defined by their covalently closed loop structure, circRNAs possess unique characteristics like high stability, abundance, and tissue-specific expression. These non-coding RNAs function through mechanisms such as miRNA sponging, interactions with RNA-binding proteins (RBPs), and modulating transcription and splicing. Advances in RNA sequencing and bioinformatics tools have enabled the identification and functional annotation of circRNAs across different cancer types. Clinically, circRNAs demonstrate high specificity and sensitivity in samples, offering potential as diagnostic and prognostic biomarkers. Additionally, therapeutic strategies involving circRNA mimics, inhibitors, and delivery systems are under investigation. However, their precise mechanisms remain unclear, and more clinical evidence is needed regarding their roles in cancer hallmarks. Understanding circRNAs will pave the way for novel diagnostic and therapeutic approaches, potentially improving patient outcomes.

Bioengineered protein nanocarrier facilitating siRNA escape from lysosomes for targeted RNAi therapy in glioblastoma

RNA interference (RNAi) represents a promising gene-specific therapy against tumors. However, its clinical translation is impeded by poor performance of lysosomal escape and tumor targeting. This challenge is especially prominent in glioblastoma (GBM) therapy, necessitating the penetration of the blood-brain barrier (BBB). Leveraging the intrinsic tumor-targeting and BBB traversing capability of human H-ferritin, we designed a series of ferritin variants with positively charged cavity and truncated carboxyl terminus, termed tHFn(+). These nanocarriers respond to weak acid and disassemble in endosomal compartments, exposing the internal positive charges to facilitate the lysosomal escape of loaded small interfering RNA (siRNA). Functioning as universal siRNA nanocarriers, tHFn(+) significantly enhanced the uptake of different siRNAs and suppressed gene expressions associated with GBM progression. Furthermore, tHFn(+) traversed the BBB and targeted glioma in vivo by binding to its receptors (e.g., transferrin receptor 1). tHFn(+)-delivered siRNAs exhibited exceptional therapeutic effects against glioma in vivo, advancing RNAi therapeutics beyond GBM for the treatment of various diseases.

A Fentanyl Hapten-Displaying Lipid Nanoparticle Vaccine that Non-Covalently Encapsulates a TLR7/8 Agonist and T-Helper Epitope Induces Protective Anti-Fentanyl Immunity

Opioid use disorder - particularly involving fentanyl - has precipitated a public health crisis characterized by a significant increase in addiction and overdose-related deaths. Fentanyl-specific immunotherapy, which aims at inducing fentanyl-specific antibodies capable of binding fentanyl molecules in the bloodstream, preventing their entry in the central nervous system, is therefore gaining momentum. Conventional opioid designs rely on the covalent conjugation of fentanyl analogues to immunogenic carrier proteins that hold the inherent capacity of mounting immunodominant responses. Here, we present an alternative fentanyl vaccine design that utilizes a non-covalent assembly of lipid nanoparticles (LNPs) to deliver fentanyl haptens in conjunction with a CD4+ T-helper peptide epitope and an imidazoquinoline TLR7/8 agonist. Our results demonstrate that a single intramuscular administration of the LNP-based nanovaccine elicits fentanyl-specific antibodies, significantly mitigating the effects of opioid overdose in preclinical mouse models. Furthermore, we analyzed the immunobiological behavior of the vaccine in vivo in mouse models, providing evidence that covalent attachment of a fentanyl hapten to a carrier proteins or peptide epitope is not necessary for inducing an effective immune response. However, co-delivery - specifically, the physical assembly of all immune cues into an LNP - remains essential for inducing hapten-specific immunity.

Self-Assembly and Biological Properties of Highly Fluorinated Oligonucleotide Amphiphiles

Nucleic acids, used as therapeutics to silence disease-related genes, offer significant advantages over small molecule drugs: they provide high specificity, the ability to target "undruggable" molecules, and adaptability to a wide range of disease phenotypes. However, their instability in biological media, as well their rapid clearance from the organism limit their applicability, necessitating the use of nanocarriers to overcome these challenges. Among these strategies, spherical nucleic acids (SNA)-composed of a densely packed corona of oligonucleotides around a nanoparticle-have emerged as a powerful tool, in particular when self-assembled from DNA amphiphiles. This non-covalent strategy however has caveats, especially when it comes to stability in complex biological media, where these SNAs disassemble in contact to serum proteins. Here, we developed highly fluorinated DNA amphiphiles that readily self-assemble into SNAs and have tunable stability profiles in biological media. They are made of branched fluorinated moieties with potentially improved biodegradability as compared to their linear counterparts. Depending on the number of fluorophilic interactions, the self-assembled SNAs can have excellent serum stabilities-up to days-and readily deliver nucleic acid therapeutics for gene silencing applications. These systems show great potential as promising candidates for nucleic acid-based therapies.

Applications of liposomes and lipid nanoparticles in cancer therapy: current advances and prospects

Liposomes and lipid nanoparticles are common lipid-based drug delivery systems and play important roles in cancer treatment and vaccine manufacture. Although significant progress has been made with these lipid-based nanocarriers in recent years, efficient clinical translation of active targeted liposomal nanocarriers remains extremely challenging. In this review, we focus on targeted liposomes, stimuli-responsive strategy and combined therapy in cancer treatment. We also summarize advances of liposome and lipid nanoparticle applications in nucleic acid delivery and tumor vaccination. In addition, we discuss limitations and challenges in the clinical translation of these lipid nanomaterials and make recommendations for the future research in cancer therapy.

Lipid nanoparticle delivery of siRNA to dorsal root ganglion neurons to treat pain

Sensory neurons within the dorsal root ganglion (DRG) are the primary trigger of pain, relaying activity about noxious stimuli from the periphery to the central nervous system; however, targeting DRG neurons for pain management has remained a clinical challenge. Here, we demonstrate the use of lipid nanoparticles (LNPs) for effective intrathecal delivery of small interfering RNA (siRNA) to DRG neurons, achieving potent silencing of the transient receptor potential vanilloid 1 (TRPV1) ion channel that is predominantly expressed in nociceptor sensory neurons. This leads to a reversible interruption of heat-, capsaicin-, and inflammation-induced nociceptive conduction, as observed by behavioral outputs. Our work provides a proof-of-concept for intrathecal siRNA therapy as a novel and selective analgesic modality.

Engineering Lipid Nanoparticles to Enhance Intracellular Delivery of Transforming Growth Factor-Beta siRNA (siTGF-β1) via Inhalation for Improving Pulmonary Fibrosis Post-Bleomycin Challenge

Background/Objectives: Transforming Growth Factor-beta (TGFβ1) plays a core role in the process of pulmonary fibrosis (PF). The progression of pulmonary fibrosis can be alleviated by siRNA-based inhibiting TGF-β1. However, the limitations of naked siRNA lead to the failure of achieving therapeutic effect. This study aimed to design lipid nanoparticles (LNPs) that can deliver siTGF-β1 to the lungs for therapeutic purposes. Methods: The cytotoxicity and transfection assay in vitro were used to screen ionizable lipids (ILs). Design of Experiments (DOE) was used to obtain novel LNPs that can enhance resistance to atomization shear forces. Meanwhile, the impact of LNPs encapsulating siTGF-β1 (siTGFβ1-LNPs) on PF was investigated. Results: When DLin-DMA-MC3 (MC3) was used as the ILs, the lipid phase ratio was MC3:DSPC:DMG-PEG2000:cholesterol = 50:10:3:37, and N/P = 3.25; the siTGFβ1-LNPs could be stably delivered to the lungs via converting the siTGFβ1-LNPs solution into an aerosol (atomization). In vitro experiments have confirmed that siTGFβ1-LNPs have high safety, high encapsulation, and can promote cellular uptake and endosomal escape. In addition, siTGFβ1-LNPs significantly reduced inflammatory infiltration and attenuated deposition of extracellular matrix (ECM) and protected the lung tissue from the toxicity of bleomycin (BLM) without causing systemic toxicity. Conclusions: The siTGFβ1-LNPs can be effectively delivered to the lungs, resulting in the silencing of TGF-β1 mRNA and the inhibition of the epithelial-mesenchymal transition pathway, thereby delaying the process of PF, which provides a new method for the treatment and intervention of PF.

Robust peptide/RNA complexes prepared with microfluidic mixing for pulmonary delivery by nebulisation

Small interfering RNA (siRNA) and messenger RNA (mRNA) have drawn considerable attention in recent years due to their ability to modulate the expression of specific disease-related proteins. However, it is difficult to find safe, robust, and effective RNA delivery systems suitable for pulmonary delivery to treat lung diseases. In this study, two cationic peptides, namely LAH4-L1 and PEG12KL4, were employed as non-viral vectors for siRNA and mRNA delivery. Four formulations (i.e. LAH4-L1/siRNA; PEG12KL4/siRNA; LAH4-L1/mRNA and PEG12KL4/mRNA) were investigated. Microfluidic mixing method was utilised to fabricate RNA complexes in a controllable and reproducible manner. Upon optimisation of the microfluidic mixing protocol, a vibrating mesh nebuliser was employed to aerosolise the RNA complexes, and their transfection efficiency was evaluated on A549 and BEAS-2B cells. Following nebulisation, inhalable mist was generated for all RNA formulations with mass median aerodynamic diameter below 5 μm. Although the hydrodynamic particle sizes of the RNA complexes were significantly reduced to around 100 nm after nebulisation regardless of the original size of the complexes prior to nebulisation, the RNA binding efficiency and the in vitro RNA transfection ability of all the peptide formulations were successfully preserved with no significant differences compared to the same system before nebulisation. The current result indicates that both LAH4-L1 and PEG12KL4 hold significant potential for future clinical application for pulmonary siRNA and mRNA delivery through nebulisation.

A ROS-responsive hydrogel encapsulated with matrix metalloproteinase-13 siRNA nanocarriers to attenuate osteoarthritis progression

RNA interference (RNAi) and oxidative stress inhibition therapeutic strategies have been extensively utilized in the treatment of osteoarthritis (OA), the most prevalent degenerative joint disease. However, the synergistic effects of these approaches on attenuating OA progression remain largely unexplored. In this study, matrix metalloproteinase-13 siRNA (siMMP-13) was incorporated onto polyethylenimine (PEI)-polyethylene glycol (PEG) modified Fe3O4 nanoparticles, forming a nucleic acid nanocarrier termed si-Fe NPs. Subsequently, a poly(vinyl alcohol) (PVA) crosslinked phenylboronic acid (PBA)-modified hyaluronic acid (HA) hydrogel (HPP) was used to encapsulate the si-Fe NPs, resulting in a bifunctional hydrogel (si-Fe-HPP) with reactive oxygen species (ROS)-responsive and RNAi therapeutic properties. Studies in vitro demonstrated that si-Fe-HPP exhibited excellent biocompatibility, anti-inflammatory effects and prolonged stable retention time in knee joint. Intra-articular injection of si-Fe-HPP significantly attenuated cartilage degradation in mice with destabilization of the medial meniscus (DMM)-induced OA. The si-Fe-HPP treatment not only notably alleviated synovitis, osteophyte formation and subchondral bone sclerosis, but also markedly improved physical activity and reduced pain in DMM-induced OA mice. This study reveals that si-Fe-HPP, with its ROS-responsive and RNAi abilities, can significantly protect chondrocytes and attenuate OA progression, providing novel insights and directions for the development of therapeutic materials for OA treatment.

Thrombospondin-1 Small Interfering RNA-Loaded Lipid Nanoparticles Inhibiting Intimal Hyperplasia of Electrospun Polycaprolactone Vascular Grafts

Synthetic vascular grafts are promising conduits for small caliber arteries. However, due to restenosis caused by intimal hyperplasia, they cannot keep long patency in vivo. In this work, through single cell RNA sequencing, we found that thrombospondin-1 (THBS1) was highly expressed in the regenerated smooth muscle cells (SMCs) in electrospun polycaprolactone (PCL) vascular grafts. The expression of THBS1 by injured SMCs was confirmed in a balloon-induced vascular injury model. Downregulation of Thbs1 expression maintained contractile phenotypes of SMCs and reduced neointimal hyperplasia after vascular injury via inhibition of FGFR1/EGR1 signaling by decreasing THBS1 expression. THBS1 small interfering RNA (THBS1-siRNA) was then loaded into macrophage membrane (MM) hybrid lipid nanoparticles (Lipid NP@MM), which were used to modify PCL vascular grafts via polydopamine (PDA) coatings. Lipid NP@MM not only protected THBS1-siRNA from degradation but also improved its internalization by SMCs to decrease the level of THBS1 expression. PCL vascular grafts modified with PDA coatings and Thbs1-siRNA-loaded Lipid NP@MM showed significantly reduced intimal hyperplasia. Thus, the downregulation of THBS1 expression in regenerated SMCs in vascular grafts is a promising strategy to inhibit intimal hyperplasia during vascular graft regeneration in vivo.

Toward a Complete Elucidation of the Primary Structure-Activity in Pentaerythritol-Based One-Component Ionizable Amphiphilic Janus Dendrimers for In Vivo Delivery of Luc-mRNA

Four-component lipid nanoparticles (LNPs) and viral vectors are key for mRNA vaccine and therapeutics delivery. LNPs contain ionizable lipids, phospholipids, cholesterol, and polyethylene glycol (PEG)-conjugated lipids and deliver mRNA for COVID-19 vaccines to liver when injected intravenously or intramuscularly. In 2021, we elaborated one-component ionizable amphiphilic Janus dendrimers (IAJDs) accessing targeted delivery of mRNA. Simplified synthesis and assembly processes allow for rapid IAJD screening for discovery. The role of the primary structure of IAJDs in activity indicated, with preliminary investigations, that ionizable amine (IA), sequence, and architecture of hydrophilic and hydrophobic domains are important for in vivo targeted delivery. Here, we study the role of the interconnecting linker length between the IA and the hydrophobic domain of pentaerythritol-based IAJDs. The linker length determines, through inductive effects, the position of the IA and the pKa of the IAJDs and through flexibility, the stability of the DNPs, highlighting their extraordinarily important role in effective targeted delivery.

Galloyl Dialkyl Lipids Drive Encapsulation of Peptides into Lipid Nanoparticles by Hydrogen Bonding

The intracellular delivery of peptides and proteins is crucial for various biomedical applications. Lipid nanoparticles (LNPs) have emerged as a promising strategy for delivering peptides to phagocytic cells. However, the diverse physicochemical properties of peptides necessitate tailored formulations. This study introduces a generic approach using galloyl (GA)-functionalized lipids for the encapsulation of peptides in LNPs via hydrogen bonding between the ubiquitously present amides in peptides and the multivalently displayed galloyl phenol groups in GA-LNPs. In vitro studies showed that GA-LNPs significantly improved the cellular uptake of peptides and activated immune responses when combined with Toll-like receptor (TLR) agonists MPLA and IMDQ. In vivo, GA-LNPs accumulated in the spleen and enhanced peptide delivery to antigen-presenting cells. GA-LNPs coencapsulating peptide antigens and TLR agonists elicited robust antigen-specific CD8+ T-cell responses in mice.

Combinatorial design of siloxane-incorporated lipid nanoparticles augments intracellular processing for tissue-specific mRNA therapeutic delivery

Systemic delivery of messenger RNA (mRNA) for tissue-specific targeting using lipid nanoparticles (LNPs) holds great therapeutic potential. Nevertheless, how the structural characteristics of ionizable lipids (lipidoids) impact their capability to target cells and organs remains unclear. Here we engineered a class of siloxane-based ionizable lipids with varying structures and formulated siloxane-incorporated LNPs (SiLNPs) to control in vivo mRNA delivery to the liver, lung and spleen in mice. The siloxane moieties enhance cellular internalization of mRNA-LNPs and improve their endosomal escape capacity, augmenting their mRNA delivery efficacy. Using organ-specific SiLNPs to deliver gene editing machinery, we achieve robust gene knockout in the liver of wild-type mice and in the lungs of both transgenic GFP and Lewis lung carcinoma (LLC) tumour-bearing mice. Moreover, we showed effective recovery from viral infection-induced lung damage by delivering angiogenic factors with lung-targeted Si5-N14 LNPs. We envision that our SiLNPs will aid in the clinical translation of mRNA therapeutics for next-generation tissue-specific protein replacement therapies, regenerative medicine and gene editing.

β-Cyclodextrin-based geometrically frustrated amphiphiles as one-component, cell-specific and organ-specific nucleic acid delivery systems

We introduce an innovative β-cyclodextrin (βCD)-prototype for delivering nucleic acids: "geometrically frustrated amphiphiles (GFAs)." GFAs are designed with cationic centers evenly distributed across the primary O6 and secondary O2 positions of the βCD scaffold, while hydrophobic tails are anchored at the seven O3 positions. Such distribution of functional elements differs from Janus-type architectures and enlarges the capacity for accessing strictly monodisperse variants. Changes at the molecular level can then be correlated with preferred self-assembly and plasmid DNA (pDNA) co-assembly behaviors. Specifically, GFAs undergo pH-dependent transition between bilayered to monolayered vesicles or individual molecules. GFA-pDNA nanocomplexes exhibit topological and internal order characteristics that are also a function of the GFA molecular architecture. Notably, adjusting the pKa of the cationic heads and the hydrophilic-hydrophobic balance, pupa-like arrangements implying axial alignments of GFA units flanked by quasi-parallel pDNA segments are preferred. In vitro cell transfection studies revealed remarkable differences in relative performances, which corresponded to distinct organ targeting outcomes in vivo. This allowed for preferential delivery to the liver and lung, kidney or spleen. The results collectively highlight cyclodextrin-based GFAs as a promising class of molecular vectors capable of finely tuning cell and organ transfection selectivity.

SUZ12-Increased NRF2 Alleviates Cardiac Ischemia/Reperfusion Injury by Regulating Apoptosis, Inflammation, and Ferroptosis

Nuclear factor erythroid 2-related factor 2 (NRF2) is a redox-sensitive transcriptional factor that enables cells to resist oxidant responses, ferroptosis and inflammation. Here, we set out to probe the effects of NRF2 on cardiomyocyte injury under acute myocardial infarction (AMI) condition and its potential mechanism. Human cardiomyocytes were exposed to hypoxia/reoxygenation (H/R) to induce cell injury. qRT-PCR and western blot assays were used to detect the levels of mRNAs and proteins. Cardiomyocyte injury was determined by detecting the levels of lactate dehydrogenase and creatine Kinase MB (CK-MB). Cell apoptosis was investigated by flow cytometry and related markers. Levels of IL-6, IL-10, and TNF-α were measured by ELISA. Cell ferroptosis was assessed by detecting the production of reactive oxygen species (ROS), malonaldehyde (MDA), reduced glutathione/oxidized glutathione disulfide (GSH/GSSG) ratio, Fe + content, and related regulators. The interaction between NRF2 and the suppressor of zest 12 (SUZ12) was analyzed by using dual-luciferase reporter and RNA immunoprecipitation assays. AMI rat models were established for in vivo analysis. NRF2 was lowly expressed in AMI patients and H/R-induced cardiomyocytes. Forced expression of NRF2 reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis. Moreover, NRF2 overexpression improved cardiac function and injury in vivo. Mechanistically, SUZ12 bound to the promoter of NRF2 and promoted its expression. Further functional analyses showed that SUZ12 overexpression reduced H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis, which were reversed by NRF2 silencing. SUZ12-increased NRF2 suppressed H/R-induced cardiomyocyte injury, apoptosis, inflammation, and ferroptosis in vitro and improved cardiac functions in rats with I/R injury, suggesting the potential cardioprotective effect of NRF2 in cardiac injury during AMI.

Lipid-Based Nanocarriers for Targeted Gene Delivery in Lung Cancer Therapy: Exploring a Novel Therapeutic Paradigm

Lung cancer is a significant cause of cancer-related death worldwide. It can be broadly categorised into small-cell lung cancer (SCLC) and Non-small cell lung cancer (NSCLC). Surgical intervention, radiation therapy, and the administration of chemotherapeutic medications are among the current treatment modalities. However, the application of chemotherapy may be limited in more advanced stages of metastasis due to the potential for adverse effects and a lack of cell selectivity. Although small-molecule anticancer treatments have demonstrated effectiveness, they still face several challenges. The challenges at hand in this context comprise insufficient solubility in water, limited bioavailability at specific sites, adverse effects, and the requirement for epidermal growth factor receptor inhibitors that are genetically tailored. Bio-macromolecular drugs, including small interfering RNA (siRNA) and messenger RNA (mRNA), are susceptible to degradation when exposed to the bodily fluids of humans, which can reduce stability and concentration. In this context, nanoscale delivery technologies are utilised. These agents offer encouraging prospects for the preservation and regulation of pharmaceutical substances, in addition to improving the solubility and stability of medications. Nanocarrier-based systems possess the notable advantage of facilitating accurate and sustained drug release, as opposed to traditional systemic methodologies. The primary focus of scientific investigation has been to augment the therapeutic efficacy of nanoparticles composed of lipids. Numerous nanoscale drug delivery techniques have been implemented to treat various respiratory ailments, such as lung cancer. These technologies have exhibited the potential to mitigate the limitations associated with conventional therapy. As an illustration, applying nanocarriers may enhance the solubility of small-molecule anticancer drugs and prevent the degradation of bio-macromolecular drugs. Furthermore, these devices can administer medications in a controlled and extended fashion, thereby augmenting the therapeutic intervention's effectiveness and reducing adverse reactions. However, despite these promising results, challenges remain that must be addressed. Multiple factors necessitate consideration when contemplating the application of nanoparticles in medical interventions. To begin with, the advancement of more efficient delivery methods is imperative. In addition, a comprehensive investigation into the potential toxicity of nanoparticles is required. Finally, additional research is needed to comprehend these treatments' enduring ramifications. Despite these challenges, the field of nanomedicine demonstrates considerable promise in enhancing the therapy of lung cancer and other respiratory diseases.

Bioengineered Nanomaterials for siRNA Therapy of Chemoresistant Cancers

Chemoresistance remains a long-standing challenge after cancer treatment. Over the last two decades, RNA interference (RNAi) has emerged as a gene therapy modality to sensitize cancer cells to chemotherapy. However, the use of RNAi, specifically small-interfering RNA (siRNA), is hindered by biological barriers that limit its intracellular delivery. Nanoparticles can overcome these barriers by protecting siRNA in physiological environments and facilitating its delivery to cancer cells. In this review, we discuss the development of nanomaterials for siRNA delivery in cancer therapy, current challenges, and future perspectives for their implementation to overcome cancer chemoresistance.

Targeted lipid nanoparticles distributed in hydrogel treat osteoarthritis by modulating cholesterol metabolism and promoting endogenous cartilage regeneration

Osteoarthritis (OA) is the most common disease in aging joints and has characteristics of cartilage destruction and inflammation. It is currently considered a metabolic disease, and the CH25H-CYP7B1-RORα axis of cholesterol metabolism in chondrocytes plays a crucial catabolic regulatory role in its pathogenesis. Targeting of this axis in chondrocytes may provide a therapeutic approach for OA treatment. Here, in this study, we propose to use a combination of stem cell-recruiting hydrogels and lipid nanoparticles (LNPs) that modulate cholesterol metabolism to jointly promote a regenerative microenvironment. Specifically, we first developed an injectable, bioactive hydrogel composed of self-assembling peptide nanofibers that recruits endogenous synovial stem cells (SMSCs) and promotes their chondrogenic differentiation. At the same time, LNPs that regulate cholesterol metabolism are incorporated into the hydrogel and slowly released, thereby improving the inflammatory environment of OA. Enhancements were noted in the inflammatory conditions associated with OA, alongside the successful attraction of mesenchymal stem cells (MSCs) from the synovial membrane. These cells were then observed to differentiate into chondrocytes, contributing to effective cartilage restoration and chondrocyte regeneration, thereby offering a promising approach for OA treatment. In summary, this approach provides a feasible siRNA-based therapeutic option, offering a potential nonsurgical solution for treatment of OA.

Nanoparticles Codelivering mRNA and SiRNA for Simultaneous Restoration and Silencing of Gene/Protein Expression In Vitro and In Vivo

RNA-based agents (siRNA, miRNA, and mRNA) can selectively manipulate gene expression/proteins and are set to revolutionize a variety of disease treatments. Nanoparticle (NP) platforms have been developed to deliver functional mRNA or siRNA inside cells to overcome their inherent limitations. Recent studies have focused on siRNA to knock down proteins causing drug resistance or mRNA technology to introduce tumor suppressors. However, cancer needs multitargeted approaches to selectively manipulate multiple gene expressions/proteins. In this proof-of-concept study, we developed NPs containing Luc-mRNA and siRNA-GFP as model agents ((M+S)-NPs) and showed that NPs can simultaneously deliver functional mRNA and siRNA and impact the expression of two genes/proteins in vitro. Additionally, after in vivo administration, (M+S)-NPs successfully knocked down GFP while introducing luciferase into a TNBC mouse model, indicating that our NPs have the potential to develop RNA-based anticancer therapeutics. These studies pave the way to develop RNA-based, multitargeted approaches for complex diseases like cancer.

Technologies for Targeted RNA Degradation and Induced RNA Decay

The vast majority of the human genome codes for RNA, but RNA-targeting therapeutics account for a small fraction of approved drugs. As such, there is great incentive to improve old and develop new approaches to RNA targeting. For many RNA targeting modalities, just binding is not sufficient to exert a therapeutic effect; thus, targeted RNA degradation and induced decay emerged as powerful approaches with a pronounced biological effect. This review covers the origins and advanced use cases of targeted RNA degrader technologies grouped by the nature of the targeting modality as well as by the mode of degradation. It covers both well-established methods and clinically successful platforms such as RNA interference, as well as emerging approaches such as recruitment of RNA quality control machinery, CRISPR, and direct targeted RNA degradation. We also share our thoughts on the biggest hurdles in this field, as well as possible ways to overcome them.

Fc-empowered exosomes with superior epithelial layer transmission and lung distribution ability for pulmonary vaccination

Mucosal vaccines offer potential benefits over parenteral vaccines for they can trigger both systemic immune protection and immune responses at the predominant sites of pathogen infection. However, the defense function of mucosal barrier remains a challenge for vaccines to overcome. Here, we show that surface modification of exosomes with the fragment crystallizable (Fc) part from IgG can deliver the receptor-binding domain (RBD) of SARS-CoV-2 to cross mucosal epithelial layer and permeate into peripheral lung through neonatal Fc receptor (FcRn) mediated transcytosis. The exosomes F-L-R-Exo are generated by genetically engineered dendritic cells, in which a fusion protein Fc-Lamp2b-RBD is expressed and anchored on the membrane. After intratracheally administration, F-L-R-Exo is able to induce a high level of RBD-specific IgG and IgA antibodies in the animals' lungs. Furthermore, potent Th1 immune-biased T cell responses were also observed in both systemic and mucosal immune responses. F-L-R-Exo can protect the mice from SARS-CoV-2 pseudovirus infection after a challenge. These findings hold great promise for the development of a novel respiratory mucosal vaccine approach.

Discovery of Ketal-Ester Ionizable Lipid Nanoparticle with Reduced Hepatotoxicity, Enhanced Spleen Tropism for mRNA Vaccine Delivery

The safety and efficacy of the lipid nanoparticle (LNP) delivery system are crucial for the successful development of messenger RNA vaccines. We designed and synthesized a series of ketal ester lipids (KELs), featuring a biodegradable ketal moiety in the linker and ester segments in the tail. Through iterative optimization of the head and tail groups of KELs, we tuned the pKa and molecular shapes, and identified (4S)-KEL12 as a safe and efficient ionizable lipid for mRNA delivery. (4S)-KEL12 LNP showed significantly higher delivery efficacy and lower toxicity than the DLin-MC3-DMA LNP. In comparison to SM-102 LNP, (4S)-KEL12 LNP exhibited better spleen tropism, reduced liver tropism, and hepatotoxicity. Additionally, (4S)-KEL12 demonstrated good biodegradability following intramuscular or intravenous injection. Notably, (4S)-KEL12 LNP encapsulated with a therapeutic mRNA cancer vaccine elicited robust cellular immune responses leading to substantial tumor regression along with prolonged survival in tumor-bearing mice. Our results suggest that (4S)-KEL12 LNP holds great promise for mRNA vaccine delivery. The comprehensive analysis of the structure-activity relationship, toxicity, biodegradability, distribution, expression, efficacy, and stereochemistry of these LNPs will greatly contribute to the rational design and discovery of novel lipid-based delivery systems.

Sustained release of MAPK14-targeting siRNA from polyelectrolyte complex hydrogels mitigates MSC osteogenesis in vitro with potential application in growth plate injury

The growth plate is a cartilage structure at the end of long bones which mediates growth in children. When fractured, the formation of bony repair tissue known as a "bony bar" can occur and cause limb deformities. There are currently no effective clinical solutions for the prevention of the bony bar formation or regeneration of healthy growth plate cartilage after a fracture. This study employs previously developed alginate/chitosan polyelectrolyte complex (PEC) hydrogels as a sustained release vehicle for the delivery of short-interfering RNA (siRNA). Specifically, the siRNA targets the p38-MAPK pathway in mesenchymal stem cells (MSCs) to prevent their osteogenic differentiation. In vitro experimental findings show sustained release of siRNA from the hydrogels for 6 months. Flow cytometry and confocal imaging indicate that the hydrogels release siRNA to effectively knockdown GFP expression over a sustained period. MAPK-14 targeting siRNA was used to knockdown the expression of MAPK-14 and correspondingly decrease the expression of other osteogenic genes in MSCs in vitro over the span of 21 days. These hydrogels were used in a rat model of growth plate injury to determine whether siMAPK-14 released from the gels could inhibit bony bar formation. No significant reduction of bony bar formation was seen in vivo at the one concentration of siRNA examined. This PEC hydrogel represents a significant advancement for siRNA sustained delivery, and presents an interesting potential therapeutic delivery system for growth plate injuries and other regenerative medicine applications.

Nucleic acid drugs: recent progress and future perspectives

High efficacy, selectivity and cellular targeting of therapeutic agents has been an active area of investigation for decades. Currently, most clinically approved therapeutics are small molecules or protein/antibody biologics. Targeted action of small molecule drugs remains a challenge in medicine. In addition, many diseases are considered 'undruggable' using standard biomacromolecules. Many of these challenges however, can be addressed using nucleic therapeutics. Nucleic acid drugs (NADs) are a new generation of gene-editing modalities characterized by their high efficiency and rapid development, which have become an active research topic in new drug development field. However, many factors, including their low stability, short half-life, high immunogenicity, tissue targeting, cellular uptake, and endosomal escape, hamper the delivery and clinical application of NADs. Scientists have used chemical modification techniques to improve the physicochemical properties of NADs. In contrast, modified NADs typically require carriers to enter target cells and reach specific intracellular locations. Multiple delivery approaches have been developed to effectively improve intracellular delivery and the in vivo bioavailability of NADs. Several NADs have entered the clinical trial recently, and some have been approved for therapeutic use in different fields. This review summarizes NADs development and evolution and introduces NADs classifications and general delivery strategies, highlighting their success in clinical applications. Additionally, this review discusses the limitations and potential future applications of NADs as gene therapy candidates.

Emerging prospects of mRNA cancer vaccines: mechanisms, formulations, and challenges in cancer immunotherapy

Cancer continues to pose an alarming threat to global health, necessitating the need for the development of efficient therapeutic solutions despite massive advances in the treatment. mRNA cancer vaccines have emerged as a hopeful avenue, propelled by the victory of mRNA technology in COVID-19 vaccines. The article delves into the intricate mechanisms and formulations of cancer vaccines, highlighting the ongoing efforts to strengthen mRNA stability and ensure successful translation inside target cells. Moreover, it discusses the design and mechanism of action of mRNA, showcasing its potential as a useful benchmark for developing efficacious cancer vaccines. The significance of mRNA therapy and selecting appropriate tumor antigens for the personalized development of mRNA vaccines are emphasized, providing insights into the immune mechanism. Additionally, the review explores the integration of mRNA vaccines with other immunotherapies and the utilization of progressive delivery platforms, such as lipid nanoparticles, to improve immune responses and address challenges related to immune evasion and tumor heterogeneity. While underscoring the advantages of mRNA vaccines, the review also addresses the challenges associated with the susceptibility of RNA to degradation and the difficulty in identifying optimum tumor-specific antigens, along with the potential solutions. Furthermore, it provides a comprehensive overview of the ongoing research efforts aimed at addressing these hurdles and enhancing the effectiveness of mRNA-based cancer vaccines. Overall, this review is a focused and inclusive impression of the present state of mRNA cancer vaccines, outlining their possibilities, challenges, and future predictions in the fight against cancer, ultimately aiding in the development of more targeted therapies against cancer.

Insight into Preventing Global Dengue Spread: Nanoengineered Niclosamide for Viral Infections

Millions of cases of dengue virus (DENV) infection yearly from Aedes mosquitoes stress the need for effective antivirals. No current drug effectively combats dengue efficiently. Transient immunity and severe risks highlight the need for broad-spectrum antivirals targeting all serotypes of DENV. Niclosamide, an antiparasitic, shows promising antiviral activity against the dengue virus, but enhancing its bioavailability is challenging. To overcome this issue and enable niclosamide to address the global dengue problem, nanoengineered niclosamides can be the solution. Not only does it address cost issues but also with its broad-spectrum antiviral effects nanoengineered niclosamide offers hope in addressing the current health crisis associated with DENV and will play a crucial role in combating other arboviruses as well.

Intestinal probiotic-based nanoparticles for cytotoxic siRNA delivery in immunotherapy against cancer

Immunogene therapy has emerged as strategy against cancer by introducing immune-stimulating components into gene therapy. However, there is still a need for an ideal platform to achieve both immune stimulation and efficient gene delivery. Lactobacillus reuteri has potential immunomodulatory activity owing to its unique antigenicity, which is potentially relevant to cancer progression. Here, we designed a novel non-viral siRNA vector (DMPLAC) by encapsulating Lactobacillus reuteri lysate in DMP. DMPLAC can promote maturation and activation of immune cells, increase infiltration of APC and cytotoxic T cells in tumor microenvironment, and exhibit tumor suppressive effects. Loading of siRNA targeting Stat3, DMPLAC/siStat3 further inhibits tumor in multiple models. We designed a strategy that combines immune activation with Stat3 silencing, triggering an immune response and tumor killing. This dual-functional design provides a new choice in development of effective immunogene therapy.