Enhancing anti-melanoma outcomes in mice using novel chitooligosaccharide nanoparticles loaded with therapeutic survivin-targeted siRNA

Dissecting the antitumor effects of Scutellaria barbata: Initial insights into the metabolism of scutellarin and luteolin by gut microbiota

The high prevalence of cancer and detrimental side effects associated with many cancer treatments necessitate the search for effective alternative therapies. Natural products are increasingly being recognized and investigated for their potential therapeutic benefits. Scutellaria barbata D. Don (SBD), a plant with potent antitumor properties, has attracted significant interest from oncology researchers. Its primary flavonoid components-scutellarin and luteolin-which have limited oral bioavailability due to poor absorption. This hinders its application for cancer treatment. The gut microbiota, which is considered a metabolic organ, can modulate the biotransformation of compounds, thereby altering their bioavailability and efficacy. In this study, we employed liquid chromatography tandem mass spectrometry (LC-MS/MS 8060) and ion trap-time of flight (LC-MSn-IT-TOF) analysis to investigate the ex vivo metabolism of scutellarin and luteolin by the gut microbiota. Five metabolites and one potential metabolite were identified. We summarized previous studies on their antitumor effects and performed in vitro tumor cell line studies to prove their antitumor activities. The possible key pathway of gut microbiota metabolism in vitro was validated using molecular docking and pure enzyme metabolic experiments. In addition, we explored the antitumor mechanisms of the two components of SBD through network pharmacology, providing a basis for subsequent target identification. These findings expand our understanding of the antitumor mechanisms of SBD. Notably, this study contributes to the existing body of knowledge regarding flavonoid biotransformation by the gut microbiota, highlighting the therapeutic potential of SBD in cancer treatment. Moreover, our results provide a theoretical basis for future in vivo pharmacokinetic studies, aiming to optimize the clinical efficacy of SBD in oncological applications.

Nanotechnology strategies to address challenges in topical and cellular delivery of siRNAs in skin disease therapy

Gene therapy is one of the most advanced therapies in current medicine. In particular, interference RNA-based therapy by small interfering RNA (siRNA) has gained attention in recent years as it is a highly versatile, selective and specific therapy. In dermatological conditions, topical delivery of siRNA offers numerous therapeutic advantages, mainly by inhibiting the expression of target transcripts directly in the skin. However, crossing the stratum corneum and overcoming intracellular barriers is an inherent challenge. Substantial efforts by scientists have moved towards the use of multimodal and multifunctional nanoparticles to overcome these barriers and achieve greater bioavailability in their site of action, the cytoplasm. In this review the most innovative strategies based on nanoparticle and physical methods are presented, as well as the design principles and the main factors that contribute to the performance of these systems. This review also highlights the synergistic contributions of medicine, nanotechnology, and molecular biology to advancing translational research into siRNA-based therapeutics for skin diseases.

Chitosan-Based Nanoparticles for Nucleic Acid Delivery: Technological Aspects, Applications, and Future Perspectives

Chitosan is a naturally occurring polymer derived from the deacetylation of chitin, which is an abundant carbohydrate found mainly in the shells of various marine and terrestrial (micro)organisms. Chitosan has been extensively used to construct nanoparticles (NPs), which are biocompatible, biodegradable, non-toxic, easy to prepare, and can function as effective drug delivery systems. Moreover, chitosan NPs have been employed in gene and vaccine delivery, as well as advanced cancer therapy, and they can also serve as new therapeutic tools against viral infections. In this review, we summarize the most recent developments in the field of chitosan-based NPs intended as nucleic acid delivery vehicles and gene therapy vectors. Special attention is given to the technological aspects of chitosan complexes for nucleic acid delivery.

Targeting active sites of inflammation using inherent properties of tissue-resident mast cells

Mast cells play a pivotal role in initiating and directing host's immune response. They reside in tissues that primarily interface with the external environment. Activated mast cells respond to environmental cues throughout acute and chronic inflammation through releasing immune mediators via rapid degranulation, or long-term de novo expression. Mast cell activation results in the rapid release of a variety of unique enzymes and reactive oxygen species. Furthermore, the increased density of mast cell unique receptors like mas related G protein-coupled receptor X2 also characterizes the inflamed tissues. The presence of these molecules (either released mediators or surface receptors) are particular to the sites of active inflammation, and are a result of mast cell activation. Herein, the molecular design principles for capitalizing on these novel mast cell properties is discussed with the goal of manipulating localized inflammation. STATEMENT OF SIGNIFICANCE: Mast cells are immune regulating cells that play a crucial role in both innate and adaptive immune responses. The activation of mast cells causes the release of multiple unique profiles of biomolecules, which are specific to both tissue and disease. These unique characteristics are tightly regulated and afford a localized stimulus for targeting inflammatory diseases. Herein, these important mast cell attributes are discussed in the frame of highlighting strategies for the design of bioresponsive functional materials to target regions of inflammations.

Recent Advancements in the Design of Nanodelivery Systems of siRNA for Cancer Therapy

RNA interference (RNAi) has increased the possibility of restoring RNA drug targets for cancer treatment. Small interfering RNA (siRNA) is a promising therapeutic RNAi tool that targets the defective gene by inhibiting its mRNA expression and stopping its translation. However, siRNAs have flaws like poor intracellular trafficking, RNase degradation, rapid kidney filtration, off-targeting, and toxicity, which limit their therapeutic efficiency. Nanocarriers (NCs) have been designed to overcome such flaws and increase antitumor activity. Combining siRNA and anticancer drugs can give synergistic effects in cancer cells, making them a significant gene-modification tool in cancer therapy. Our discussion of NCs-mediated siRNA delivery in this review includes their mechanism, limitations, and advantages in comparison with naked siRNA delivery. We will also discuss organic NCs (polymers and lipids) and inorganic NCs (quantum dots, carbon nanotubes, and gold) that have been reported for extensive delivery of therapeutic siRNA to tumor sites. Finally, we will conclude by discussing the studies based on organic and inorganic NCs-mediated siRNA drug delivery systems conducted in the years 2020 and 2021.

Advances in nanotechnology-based platforms for survivin-targeted drug discovery

INTRODUCTION

Due to its unique functional impact on multiple cancer cell circuits including proliferation, apoptosis, tumor dissemination, DNA damage repair and immune response, the inhibitor of apoptosis protein (IAP) survivin has gained high interest as a molecular target and a multitude of therapeutics were developed to interfere with survivin expression and functionality. First clinical evaluations of these therapeutics, however, were disappointing highlighting the need to develop advanced delivery systems of survivin-targeting molecules to increase stability, bioavailability as well as the selective guidance to tumor tissue.

AREAS COVERED

: This review focuses on advancements in nanocarriers to molecularly target survivin in human malignancies. A plethora of nanoparticle platforms, including liposomes, polymeric systems, dendrimers, inorganic nanocarriers, RNA/DNA nanotechnology and exosomes are discussed in the background of survivin-tailored RNA interference, small molecule inhibitors, dominant negative mutants or survivin vaccination or combined modality treatment with chemotherapeutic drugs and photo- dynamic/photothermal strategies.

EXPERT OPINION

Novel therapeutic approaches include the use of biocompatible nanoformulations carrying gene silencing or drug molecules to directly or indirectly target proteins, allow for a more precise and controlled delivery of survivin therapeutics. Moreover, surface modification of these nanocarriers may result in a tumor entity specific delivery. Therefore, nanomedicine exploiting survivin-tailored strategies in a multimodal background is considered the way forwaerd to enhance the development of future personalized medicine.

Prolonged cultured human hepatocytes as an in vitro experimental system for the evaluation of potency and duration of activity of RNA therapeutics: Demonstration of prolonged duration of gene silencing effects of a GalNAc-conjugated human hypoxanthine phosphoribosyl transferase (HPRT1) siRNA

We report here the evaluation of a novel in vitro experimental model, prolonged cultured human hepatocytes (PCHC), as an experimental system to evaluate the potency and duration of effects of oligonucleotide therapeutics. A novel observation was made on the redifferentiation of PCHC upon prolonged culturing based on mRNA profiling of characteristic hepatic differentiation marker genes albumin, transferrin, and transthyretin. Consistent with the known de-differentiation of cultured human hepatocytes, decreases in marker gene expression were observed upon culturing of the hepatocytes for 2 days. A novel observation of re-differentiation was observed on day 7 as demonstrated by an increase in expression of the marker genes to levels similar to that observed on the first day of culture. The expression of the differentiation marker genes was highest on day 7, followed by a gradual decrease but remained higher than that on day 2 for up to the longest culture duration evaluated of 41 days. The redifferentiation phenomenon suggests that PCHC may be useful for the evaluation of the duration of effects of oligonucleotide therapeutics on gene expression in human hepatocytes. A proof of concept study was thereby conducted with PCHC with a GalNAc-conjugated siRNA targeting human hypoxanthine phosphoribosyl transferase1 (HPRT1). HPRT1 mRNA expression in siRNA-treated cultures decreased to 21% of that in untreated hepatocytes on day 1, <10% from days 2 to 12, <20% from days 16 to 33, and eventually recovered to 64% by day 41. Our results suggest that PCHC represent a clinically-relevant cost- and time-efficient experimental tool to aid in the evaluation of GalNAc-siRNA silencing activity, providing information on both efficacy and duration of efficacy. PCHC may be applicable in the drug development setting as a species- and cell type-relevant experimental tool to aid the development of oligonucleotide therapeutics.