Design of Peptidomimetic Functionalized Cholesterol Based Lipid Nanoparticles for Efficient Delivery of Therapeutic Nucleic Acids

mRNA vaccines as cancer therapies

ABSTRACT

Cancer remains a major global health challenge, with conventional treatments like chemotherapy and radiotherapy often hindered by significant side effects, lack of specificity, and limited efficacy in advanced cases. Among emerging therapeutic strategies, mRNA vaccines have shown remarkable potential due to their adaptability, rapid production, and capability for personalized cancer treatment. This review provides an in-depth analysis of messenger RNA (mRNA) vaccines as a therapeutic approach for cancer immunotherapy, focusing on their molecular biology, classification, mechanisms, and clinical studies. Derived from reported literature and data on clinicaltrials.gov, it examines studies on mRNA vaccines encoding tumor-specific antigens (TSAs), tumor-associated antigens (TAAs), immunomodulators, and chimeric antigen receptors (CARs) across various cancer types. The review highlights the ability of mRNA vaccines to encode TSAs and TAAs, enabling personalized cancer treatments, and classifies these vaccines into non-replicating and self-amplifying types. It further explores their mechanisms of action, including antigen presentation and immune activation, while emphasizing findings from clinical studies that demonstrate the potential of mRNA vaccines in cancer therapy. Despite their promise, challenges remain in enhancing delivery systems, improving immunogenicity, and addressing tumor heterogeneity. Overcoming these obstacles will require further investigation to fully harness the potential of mRNA vaccines in personalized cancer treatment.

Small interfering RNA-based nanotherapeutics for treating skin-related diseases

INTRODUCTION

RNA interference (RNAi) has demonstrated great potential in treating skin-related diseases, as small interfering RNA (siRNA) can efficiently silence specific genes. The design of skin delivery systems for siRNA is important to protect the nucleic acid while facilitating both skin targeting and cellular ingestion. Entrapment of siRNA into nanocarriers can accomplish these aims, contributing to improved targeting, controlled release, and increased transfection.

AREAS COVERED

The siRNA-based nanotherapeutics for treating skin disorders are summarized. First, the mechanisms of RNAi are presented, followed by the introduction of challenges for skin therapy. Then, the different nanoparticle types used for siRNA skin delivery are described. Subsequently, we introduce the mechanisms of how nanoparticles enhance siRNA skin penetration. Finally, the current investigations associated with nanoparticulate siRNA application in skin disease management are reviewed.

EXPERT OPINION

The potential application of nanotherapeutic RNAi allows for a novel skin application strategy. Further clinical studies are required to confirm the findings in the cell-based or animal experiments. The capability of large-scale production and reproducibility of nanoparticle products are also critical for translation to commercialization. siRNA delivery by nanocarriers should be optimized to attain cutaneous targeting without the risk of toxicity.

Nanodelivery systems for cutaneous melanoma treatment

Cutaneous melanoma (CM) is a multifactorial disease whose treatment still presents challenges: the rapid progression to advanced CM, which leads to frequent recurrences even after surgical excision and, notably, the low response rates and resistance to the available therapies, particularly in the case of unresectable metastatic CM. Thereby, alternative innovative therapeutic approaches for CM continue to be searched. In this review we discuss relevant preclinical research studies, and provide a broad-brush analysis of patents and clinical trials which involve the application of nanotechnology-based delivery systems in CM therapy. Nanodelivery systems have been developed for the delivery of anticancer biomolecules to CM, which can be administered by different routes. Overall, nanosystems could promote technological advances in several therapeutic modalities and can be used in combinatorial therapies. Nevertheless, the results of these preclinical studies have not been translated to clinical applications. Thus, concerted and collaborative research studies involving basic, applied, translational, and clinical scientists need to be performed to allow the development of effective and safe nanomedicines to treat CM.

Peptidomimetics in cancer targeting

The low efficiency of treatment strategies is one of the main obstacles to developing cancer inhibitors. Up to now, various classes of therapeutics have been developed to inhibit cancer progression. Peptides due to their small size and easy production compared to proteins are highly regarded in designing cancer vaccines and oncogenic pathway inhibitors. Although peptides seem to be a suitable therapeutic option, their short lifespan, instability, and low binding affinity for their target have not been widely applicable against malignant tumors. Given the peptides' disadvantages, a new class of agents called peptidomimetic has been introduced. With advances in physical chemistry and biochemistry, as well as increased knowledge about biomolecule structures, it is now possible to chemically modify peptides to develop efficient peptidomimetics. In recent years, numerous studies have been performed to the evaluation of the effectiveness of peptidomimetics in inhibiting metastasis, angiogenesis, and cancerous cell growth. Here, we offer a comprehensive review of designed peptidomimetics to diagnose and treat cancer.

Microfluidic-Based Cationic Cholesterol Lipid siRNA Delivery Nanosystem: Highly Efficient In Vitro Gene Silencing and the Intracellular Behavior

Safe and efficient delivery of small interfering RNA (siRNA) is essential to gene therapy towards intervention of genetic diseases. Herein, we developed a novel cationic cholesterol lipid derivative (CEL) in which cholesterol hydrophobic skeleton was connected to L-lysine cationic headgroup via a hexanediol linker as the non-viral siRNA delivery carrier. Well-organized CEL/siRNA nanocomplexes (100-200 nm) were prepared by microfluidic-assisted assembly of CEL and siRNA at various N/P ratios. The CEL and CEL/siRNA nanocomplexes have lower cytotoxicity compared with bPEI25k. Delightfully, we disclosed that, in Hela-Luc and H1299-Luc cell lines, the micro-fluidic-based CEL/siRNA nanocomplexes exhibited high siRNA transfection efficiency under both serum-free condition (74-98%) and low-serum circumstances (80-87%), higher than that of lipofectamine 2000. These nanocomplexes also showed high cellular uptake through the caveolae/lipid-raft mediated endocytosis pathway, which may greatly contribute to transfection efficiency. Moreover, the time-dependent (0-12 h) dynamic intracellular imaging demonstrated the efficient delivery to cytoplasm after lysosomal co-localization. The results indicated that the microfluidic-based CEL/siRNA nanosystems possessed good stability, low cytotoxicity, high siRNA delivery efficiency, rapid cellular uptake and caveolae/lipid raft-dependent internalization. Additionally, this study provides a simple approach for preparing and applying a "helper lipid-free" cationic lipid siRNA delivery system as potential nanotherapeutics towards gene silencing treatment of (tumor) diseases.

Silencing of STAT3 via Peptidomimetic LNP-Mediated Systemic Delivery of RNAi Downregulates PD-L1 and Inhibits Melanoma Growth

Cutaneous melanoma is the most aggressive skin cancer with notorious drug resistance. Inhibition of immune checkpoint molecules is one of the most promising approaches for cancer therapy. Herein, we show that RNAi mediated silencing of STAT3 expression in the tumor tissue robustly inhibit tumor growth in B16F10 mouse model of melanoma. We designed a peptidomimetic-based lipid nanoparticles (LNPs) for the delivery of siRNA in mouse model of melanoma. When systemically administered, the novel formulation (denote DoCh) preferentially delivered siRNA to the tumor tissue. Remarkably, sequential intravenous injections of siRNA against STAT3 induced profound silencing of STAT3 expression in tumor tissue, which resulted in significant downregulation of PD-L1, leading to significant inhibition of tumor growth through inhibition of tumor immune checkpoint. Moreover, DoCh-mediated siRNA delivery did not show noticeable damage to the major organs. Collectively, our data demonstrated that DoCh LNP is a promising tumor-targeted siRNA delivery system.