Neutral PEGylated liposomal formulation for efficient folate-mediated delivery of MCL1 siRNA to activated macrophages

Drug Delivery System Approaches for Rheumatoid Arthritis Treatment: A Review

Rheumatoid arthritis (RA) is a chronic autoimmune disease that has traditionally been treated using a variety of pharmacological compounds. However, the effectiveness of these treatments is often limited due to challenges associated with their administration. Oral and parenteral routes of drug delivery are often restricted due to issues such as low bioavailability, rapid metabolism, poor absorption, first-pass effect, and severe side effects. In recent years, nanocarrier-based delivery methods have emerged as a promising alternative for overcoming these challenges. Nanocarriers, including nanoparticles, dendrimers, micelles, nanoemulsions, and stimuli-sensitive carriers, possess unique properties that enable efficient drug delivery and targeted therapy. Using nanocarriers makes it possible to circumvent traditional administration routes' limitations. One of the key advantages of nanocarrier- based delivery is the ability to overcome resistance or intolerance to traditional antirheumatic therapies. Moreover, nanocarriers offer improved drug stability, controlled release kinetics, and enhanced solubility, optimizing the therapeutic effect. They can also protect the encapsulated drug, prolonging its circulation time and facilitating sustained release at the target site. This targeted delivery approach ensures a higher concentration of the therapeutic agent at the site of inflammation, leading to improved therapeutic outcomes. This article explores potential developments in nanotherapeutic regimens for RA while providing a comprehensive summary of current approaches based on novel drug delivery systems. In conclusion, nanocarrier-based drug delivery systems have emerged as a promising solution for improving the treatment of rheumatoid arthritis. Further advancements in nanotechnology hold promise for enhancing the efficacy and safety of RA therapies, offering new hope for patients suffering from this debilitating disease.

Overcoming delivery barriers for RNA therapeutics in the treatment of rheumatoid arthritis

RNA therapeutics can manipulate gene expression or protein production, making them suitable for treating a wide range of diseases. Theoretically, any disease that has a definite biological target would probably find feasible therapeutic approach from RNA-based therapeutics. Numerous clinical trials using RNA therapeutics fighting against cancer, infectious diseases or inherited diseases have been reported and achieved desirable therapeutic efficacy. So far, encouraging findings from various animal experimental studies have also confirmed the great potential of RNA-based therapies in the treatment of rheumatic arthritis (RA). However, the in vivo multiple physiological barriers still seriously compromise the therapeutic efficacy of RNA drugs. Thus, safe and effective delivery strategies for RNA therapeutics are quite essential for their further and wide application in RA therapy. In this review, we will discuss the recent progress achieved using RNA-based therapeutics and focus on delivery strategies that can overcome the in vivo delivery barriers in RA treatment. Furthermore, discussion about the existing problems in current RNA delivery systems for RA therapy has been also included here.

Pro-inflammatory polarization and colorectal cancer modulate alternative and intronic polyadenylation in primary human macrophages

Introduction

Macrophages are essential cells of the immune system that alter their inflammatory profile depending on their microenvironment. Alternative polyadenylation in the 3'UTR (3'UTR-APA) and intronic polyadenylation (IPA) are mechanisms that modulate gene expression, particularly in cancer and activated immune cells. Yet, how polarization and colorectal cancer (CRC) cells affect 3'UTR-APA and IPA in primary human macrophages was unclear.

Methods

In this study, we isolated primary human monocytes from healthy donors, differentiated and polarized them into a pro-inflammatory state and performed indirect co-cultures with CRC cells. ChrRNA-Seq and 3'RNA-Seq was performed to quantify gene expression and characterize new 3'UTR-APA and IPA mRNA isoforms.

Results

Our results show that polarization of human macrophages from naïve to a pro-inflammatory state causes a marked increase of proximal polyA site selection in the 3'UTR and IPA events in genes relevant to macrophage functions. Additionally, we found a negative correlation between differential gene expression and IPA during pro-inflammatory polarization of primary human macrophages. As macrophages are abundant immune cells in the CRC microenvironment that either promote or abrogate cancer progression, we investigated how indirect exposure to CRC cells affects macrophage gene expression and 3'UTR-APA and IPA events. Co-culture with CRC cells alters the inflammatory phenotype of macrophages, increases the expression of pro-tumoral genes and induces 3'UTR-APA alterations. Notably, some of these gene expression differences were also found in tumor-associated macrophages of CRC patients, indicating that they are physiologically relevant. Upon macrophage pro-inflammatory polarization, SRSF12 is the pre-mRNA processing gene that is most upregulated. After SRSF12 knockdown in M1 macrophages there is a global downregulation of gene expression, in particular in genes involved in gene expression regulation and in immune responses.

Discussion

Our results reveal new 3'UTR-APA and IPA mRNA isoforms produced during pro-inflammatory polarization of primary human macrophages and CRC co-culture that may be used in the future as diagnostic or therapeutic tools. Furthermore, our results highlight a function for SRSF12 in pro-inflammatory macrophages, key cells in the tumor response.

Potential of siRNA in COVID-19 therapy: Emphasis on in silico design and nanoparticles based delivery

Small interfering RNA (siRNA)-mediated mRNA degradation approach have imparted its eminence against several difficult-to-treat genetic disorders and other allied diseases. Viral outbreaks and resulting pandemics have repeatedly threatened public health and questioned human preparedness at the forefront of drug design and biomedical readiness. During the recent pandemic caused by the SARS-CoV-2, mRNA-based vaccination strategies have paved the way for a new era of RNA therapeutics. RNA Interference (RNAi) based approach using small interfering RNA may complement clinical management of the COVID-19. RNA Interference approach will primarily work by restricting the synthesis of the proteins required for viral replication, thereby hampering viral cellular entry and trafficking by targeting host as well as protein factors. Despite promising benefits, the stability of small interfering RNA in the physiological environment is of grave concern as well as site-directed targeted delivery and evasion of the immune system require immediate attention. In this regard, nanotechnology offers viable solutions for these challenges. The review highlights the potential of small interfering RNAs targeted toward specific regions of the viral genome and the features of nanoformulations necessary for the entrapment and delivery of small interfering RNAs. In silico design of small interfering RNA for different variants of SARS-CoV-2 has been discussed. Various nanoparticles as promising carriers of small interfering RNAs along with their salient properties, including surface functionalization, are summarized. This review will help tackle the real-world challenges encountered by the in vivo delivery of small interfering RNAs, ensuring a safe, stable, and readily available drug candidate for efficient management of SARS-CoV-2 in the future.

Small interfering RNAs in the management of human rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) has unclear pathogenesis, but the molecules that feed its inflammatory state are known. Small interfering RNAs (siRNAs) are useful to identify molecular targets and evaluate the efficacy of specific drugs, and can themselves be used for therapeutic purposes.

SOURCES OF DATA

A systematic search of different databases to March 2022 was performed to define the role of siRNAs in RA therapy. Twenty suitable studies were identified.

AREAS OF AGREEMENT

Small interfering RNAs can be useful in the study of inflammatory processes in RA, and identify possible therapeutic targets and drug therapies.

AREAS OF CONTROVERSY

Many genes and cytokines participate in the inflammatory process of RA and can be regulated with siRNA. However, it is difficult to determine whether the responses to siRNAs and other drugs studied in human cells in vitro are similar to the responses in vivo.

GROWING POINTS

Inflammatory processes can be affected by the gene dysregulation of siRNAs on inflammatory cytokines.

AREAS TIMELY FOR DEVELOPING RESEARCH

To date, it is not possible to determine whether the pharmacological response of siRNAs on cells in vitro would be similar to what takes place in vivo for the diseases studied so far.

Combined Inhibition of FOSL-1 and YAP Using siRNA-Lipoplexes Reduces the Growth of Pancreatic Tumor

Simple Summary

Intercepting the molecular mechanisms implicated in pancreatic cancer progression can be an efficient therapeutic approach to treat this aggressive tumor. The Hippo pathway is a key mechanism driving tumor progression, even in the absence of KRAS activation. When this pathway is switched off, the transcriptional coactivator YAP is translocated into the nucleus and induces the activation of several genes implicated in tumor progression and apoptosis inhibition. FOSL-1 is a transcription factor that synergizes with YAP, forming a transcriptional complex. It has been shown to have a good therapeutic outcome when they are individually inhibited. In this work, we showed for the first time that the combined inhibition of YAP and FOSL-1 mRNA expression, using siRNA-lipoplexes, induces superior control over tumor growth in vitro and in vivo, compared to the individual treatments, and a reduction of the tumor stroma. The results offer a new therapeutic approach for pancreatic cancer treatment.

Abstract

Pancreatic cancer evades most of the current therapies and there is an urgent need for new treatments that could efficiently eliminate this aggressive tumor, such as the blocking of routes driving cell proliferation. In this work, we propose the use of small interfering RNA (siRNA) to inhibit the combined expression of FOSL-1 and YAP, two signaling proteins related with tumor cell proliferation and survival. To improve the efficacy of cell transfection, DODAB:MO (1:2) liposomes were used as siRNA nanocarriers, forming a complex denominated siRNA-lipoplexes. Liposomes and lipoplexes (carrying two siRNA for each targeted protein, or the combination of four siRNAs) were physico-chemically and biologically characterized. They showed very good biocompatibility and stability. The efficient targeting of FOSL-1 and YAP expression at both mRNA and protein levels was first proved in vitro using mouse pancreatic tumoral cell lines (KRAS^G12V and p53 knockout), followed by in vivo studies using subcutaneous allografts on mice. The peri-tumoral injection of lipoplexes lead to a significant decrease in the tumor growth in both Athymic Nude-Foxn1^nu and C57BL/6 mice, mainly in those receiving the combination of four siRNAs, targeting both YAP and FOSL-1. These results open a new perspective to overcome the fast tumor progression in pancreatic cancer.

Nanotechnology-enabled immunoengineering approaches to advance therapeutic applications

Immunotherapy has reached clinical success in the last decade, with the emergence of new and effective treatments such as checkpoint blockade therapy and CAR T-cell therapy that have drastically improved patient outcomes. Still, these therapies can be improved to limit off-target effects, mitigate systemic toxicities, and increase overall efficacies. Nanoscale engineering offers strategies that enable researchers to attain these goals through the manipulation of immune cell functions, such as enhancing immunity against cancers and pathogens, controlling the site of immune response, and promoting tolerance via the delivery of small molecule drugs or biologics. By tuning the properties of the nanomaterials, such as size, shape, charge, and surface chemistry, different types of immune cells can be targeted and engineered, such as dendritic cells for immunization, or T cells for promoting adaptive immunity. Researchers have come to better understand the critical role the immune system plays in the progression of pathologies besides cancer, and developing nanoengineering approaches that seek to harness the potential of immune cell activities can lead to favorable outcomes for the treatment of injuries and diseases.

miRNA Delivery by Nanosystems: State of the Art and Perspectives

MicroRNAs (miRNAs) are short (~21-23 nucleotides), non-coding endogenous RNA molecules that modulate gene expression at the post-transcriptional level via the endogenous RNA interference machinery of the cell. They have emerged as potential biopharmaceuticals candidates for the treatment of various diseases, including cancer, cardiovascular and metabolic diseases. However, in order to advance miRNAs therapeutics into clinical settings, their delivery remains a major challenge. Different types of vectors have been investigated to allow the delivery of miRNA in the diseased tissue. In particular, non-viral delivery systems have shown important advantages such as versatility, low cost, easy fabrication and low immunogenicity. Here, we present a general overview of the main types of non-viral vectors developed for miRNA delivery, with their advantages, limitations and future perspectives.

Legumain protease-sheddable PEGylated, tuftsin-modified nanoparticles for selective targeting to tumor-associated macrophages

Tumor-associated macrophages (TAMs) represent an attractive cell target for anticancer therapy. However, selective and efficient targeting of TAMs remains difficult. Here, we constructed a novel dually functionalized nanoparticle platform (s-T_pep-NPs) by surface co-modification of nanoparticles (NPs) with tuftsin (T_pep) and legumain protease-sheddable polyethylene glycol 5k (PEG_5k) to achieve selective targeted delivery to TAMs. The fluorescence resonance energy transfer experiment and in vitro cellular uptake assay confirmed that s-T_pep-NPs can responsively shed PEG_5k and transform into active T_pep-NPs upon the cleavage of legumain that is overexpressed on TAM surfaces, which then promotes TAM phagocytosis through Fc receptor-mediated pathways. Owing to the shielding effect by legumain-sheddable PEG_5k, s-T_pep-NPs can effectively decrease the T_pep-induced non-specific accumulation in mononuclear phagocyte system (MPS) organs during systemic circulation. Moreover, s-T_pep-NPs can significantly enhance the tumoral accumulation and improve the specificity and efficiency of targeting to TAMs, as compared with both controls of T_pep-NPs and non-sheddable ns-T_pep-NPs. Overall, this study provides a robust nanoplatform with a novel avenue for improved selectivity of targeted delivery to TAMs.

PLGA/PCADK composite microspheres containing hyaluronic acid-chitosan siRNA nanoparticles: A rational design for rheumatoid arthritis therapy

Myeloid cell leukemia-1 (Mcl-1), a member of the Bcl-2 anti-apoptotic family, is overexpressed in the synovial macrophages of patients with rheumatoid arthritis (RA). Small interfering RNA (siRNA) Mcl-1 can induce macrophage apoptosis in the joints and is a potential therapeutic target of RA. Nevertheless, the application of siRNA is limited owing to its instability and susceptibility to degradation in vivo. To address these shortcomings, we developed composite microspheres (MPs) loaded with hyaluronic acid (HA)-chitosan (CS) nanoparticles (NPs). First, we synthesized HA-CS/siRNA NPs (HCNPs) using ionotropic gelation process. Then, HCNPs, as an internal aqueous phase, were loaded into poly (D, L-lactide-co-glycolide) (PLGA) and poly (cyclohexane-1,4-diyl acetone dimethylene ketal) (PCADK) MPs using the double emulsion method. The NPs-in-MPs (NiMPs) composite system provided sustained release of NPs, protected siRNA against nuclease degradation in the serum, and could readily cross the cellular membrane. In addition, we evaluated the advantages of NiMPs in an adjuvant-induced arthritis rat model. Our experimental results demonstrate that NiMPs have greater pharmacodynamic effects than common MPs. Meanwhile, compared with HCNPs, NiMPs reduced the frequency of drug administration. Therefore, NiMPs are a promising and novel siRNA delivery vehicle for RA therapy.

Multi-Component Hydrogel Beads Incorporated with Reduced Graphene Oxide for pH-Responsive and Controlled Co-Delivery of Multiple Agents

The development of combination therapy has received great attention in recent years because of its potential to achieve higher therapeutic efficacy than that achieved by mono-drug therapy. Carriers for effective and stimuli-responsive co-delivery of multiple agents, however, are highly deficient at the moment. To address this need, this study reports the generation of multi-component hydrogel beads incorporated with reduced graphene oxide (rGO). The beads are prepared by incorporating doxorubicin (DOX)-loaded gelatine (GL) microbeads into hydrogel beads containing rGO and 5-fluorouracil (5-FU). rGO-containing beads are shown to be more effective in inhibiting the growth of MCF-7 cells via the induction of reactive oxygen species (ROS) generation. In addition, the drug release sustainability of the beads is affected by the pH of the release medium, with the release rate increasing in neutral pH but decreasing in the acidic environment. Our beads warrant further development as carriers for pH-responsive and controlled co-delivery of multiple agents.

Exosome-like Nanoparticles: A New Type of Nanocarrier

Nanoparticles are one of the most commonly used systems for imaging or therapeutic drug delivery. Exosomes are nanovesicular carriers that transport cargo for intercellular communication. These nanovesicles are linked to the pathology of some major diseases, in some cases with a central role in their progression. The use of these carriers to transport therapeutic drugs is a recent and promising approach to treat diseases such as cancer and Alzheimer disease. The physiological production of these structures is limited impairing its collection and subsequent purification. These drawbacks inspired the search for mimetic alternatives. The collection of exosome-like nanoparticles from plants can be a good alternative, since they are easier to extract and do not have the drawbacks of those produced in animal cells. Both natural and synthetic exosome-like nanoparticles, produced from serial extrusion of cells or by bottom up synthesis, are currently some of the most promising, biocompatible, high efficiency systems for drug delivery.

Targeted drug-delivery systems in the treatment of rheumatoid arthritis: recent advancement and clinical status

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that is characterized by synovial inflammation, cellular infiltration in joints which leads to progressive joint destruction and bone erosion. RA is associated with many comorbidities including pulmonary disease, rheumatoid nodules and can have a pessimistic impact on quality of life. The current therapies of RA treatment comprise conventional, small molecule and biological antirheumatic drugs. Their utility as therapeutic agents is limited because of poor absorption, rapid metabolism and adverse effects (dose-escalation, systemic toxicity, lack of selectivity and safety). To overcome these limitations, the novel drug delivery systems are being investigated. This review has compiled currently approved therapies along with emerging advanced drug-delivery systems for RA treatment. Further, active targeting of therapeutic agents to inflamed joints via folate receptor, CD44, angiogenesis, integrins and other provided an improved therapeutic efficacy in the treatment of RA.

Lipid-based Nanocarriers for siRNA Delivery: Challenges, Strategies and the Lessons Learned from the DODAX: MO Liposomal System

The possibility of using the RNA interference (RNAi) mechanisms in gene therapy was one of the scientific breakthroughs of the last century. Despite the extraordinary therapeutic potential of this approach, the need for an efficient gene carrier is hampering the translation of the RNAi technology to the clinical setting. Although a diversity of nanocarriers has been described, liposomes continue to be one of the most attractive siRNA vehicles due to their relatively low toxicity, facilitated siRNA complexation, high transfection efficiency and enhanced pharmacokinetic properties. This review focuses on RNAi as a therapeutic approach, the challenges to its application, namely the nucleic acids' delivery process, and current strategies to improve therapeutic efficacy. Additionally, lipid-based nanocarriers are described, and lessons learned from the relation between biophysical properties and biological performance of the dioctadecyldimethylammonium:monoolein (DODAX: MO) system are explored. Liposomes show great potential as siRNA delivery systems, being safe nanocarriers to protect nucleic acids in circulation, extend their half-life time, target specific cells and reduce off-target effects. Nevertheless, several issues related to delivery must be overcome before RNAi therapies reach their full potential, namely target-cell specificity and endosomal escape. Understanding the relationship between biophysical properties and biological performance is an essential step in the gene therapy field.

Liposomal delivery of CRISPR/Cas9

Liposomes are one of the most widely investigated carriers for CRISPR/Cas9 delivery. The surface properties of liposomal carriers, including the surface charge, PEGylation, and ligand modification can significantly affect the gene silencing efficiency. Three barriers of systemic CRISPR/Cas9 delivery (long blood circulation, efficient tumor penetration, and efficient cellular uptake/endosomal escape) are analyzed on liposomal carriers with different surface charges, PEGylations, and ligand modifications. Cationic formulations dominate CRISPR/Cas9 delivery and neutral formulations also have good performance while anionic formulations are generally not proper for CRISPR/Cas9 delivery. The PEG dilemma (prolonged blood circulation vs. reduced cellular uptake/endosomal escape) and the side effect of repeated PEGylated formulation (accelerated blood clearance) were discussed. Effects of ligand modification on cationic and neutral formulations were analyzed. Finally, we summarized the achievements in liposomal CRISPR/Cas9 delivery, outlined existing problems, and provided some future perspectives. Liposomes are one of the most widely investigated carriers for CRISPR/Cas9 delivery. The surface properties of liposomal carriers, including the surface charge, PEGylation, and ligand modification can significantly affect the gene silencing efficiency. Three barriers of systemic siRNA delivery (long blood circulation, efficient tumor penetration, and efficient cellular uptake/endosomal escape) are analyzed on liposomal carriers with different surface charges, PEGylations, and ligand modifications. Cationic formulations dominate CRISPR/Cas9 delivery and neutral formulations also have good performance while anionic formulations are generally not proper for CRISPR/Cas9 delivery. The PEG dilemma (prolonged blood circulation vs. reduced cellular uptake/endosomal escape) and the side effect of repeated PEGylated formulation (accelerated blood clearance) were discussed. Effects of ligand modification on cationic and neutral formulations were analyzed. Finally, we summarized the achievements in liposomal CRISPR/Cas9 delivery, outlined existing problems, and provided some future perspectives.

The folate receptor β as a macrophage-mediated imaging and therapeutic target in rheumatoid arthritis

Macrophages play a key role in the pathophysiology of rheumatoid arthritis (RA). Notably, positive correlations have been reported between synovial macrophage infiltration and disease activity as well as therapy outcome in RA patients. Hence, macrophages can serve as an important target for both imaging disease activity and drug delivery in RA. Folate receptor β (FRβ) is a glycosylphosphatidyl (GPI)-anchored plasma membrane protein being expressed on myeloid cells and activated macrophages. FRβ harbors a nanomolar binding affinity for folic acid allowing this receptor to be exploited for RA disease imaging (e.g., folate-conjugated PET tracers) and therapeutic targeting (e.g., folate antagonists and folate-conjugated drugs). This review provides an overview of these emerging applications in RA by summarizing and discussing properties of FRβ, expression of FRβ in relation to macrophage polarization, FRβ-targeted in vivo imaging modalities, and FRβ-directed drug targeting.

Strategies for improving the specificity of siRNAs for enhanced therapeutic potential

INTRODUCTION

RNA interference has become a tool of choice in the development of drugs in various therapeutic areas of Post Transcriptional Gene Silencing (PTGS). The critical element in developing successful RNAi therapeutics lies in designing small interfering RNA (siRNA) using an efficient algorithm satisfying the designing criteria. Further, translation of siRNA from bench-side to bedside needs an efficient delivery system and/or chemical modification. Areas covered: This review emphasizes the importance of dicer, the criteria for efficient siRNA design, the currently available algorithms and strategies to overcome off-target effects, immune stimulatory effects and endosomal trap. Expert opinion: Specificity and stability are the primary concerns for siRNA therapeutics. The design criteria and algorithms should be chosen rationally to have a siRNA sequence that binds to the corresponding mRNA as it happens in the Watson and Crick base pairing. However, it must evade a few more hurdles (Endocytosis, Serum stability etc.) to be functional in the cytosol.

Enhancing the Therapeutic Delivery of Oligonucleotides by Chemical Modification and Nanoparticle Encapsulation

Oligonucleotide (ON) drugs, including small interfering RNA (siRNA), microRNA (miRNA) and antisense oligonucleotides, are promising therapeutic agents. However, their low membrane permeability and sensitivity to nucleases present challenges to in vivo delivery. Chemical modifications of the ON offer a potential solution to improve the stability and efficacy of ON drugs. Combined with nanoparticle encapsulation, delivery at the site of action and gene silencing activity of chemically modified ON drugs can be further enhanced. In the present review, several types of ON drugs, selection of chemical modification, and nanoparticle-based delivery systems to deliver these ON drugs are discussed.