Glioblastoma Multiforme Selective Nanomedicines for Improved Anti-Cancer Treatments

Insights into 2D and 3D cell culture models for nanoparticle-based drug delivery to glioblastoma

Glioblastoma (GBM) remains a formidable challenge due to its aggressive nature, protected location within the brain, and resistance to conventional treatments. Its complex tumor microenvironment (TME), coupled with the blood-brain barrier (BBB), hinders drug delivery leading to poor treatment outcomes. Nanoparticles (NPs) offer a promising solution, as they can improve the pharmacokinetic properties of anticancer agents. By functionalizing NPs with targeting molecules, researchers aim to enhance drug concentration in the brain. However, developing effective NP-based therapies requires robust in vitro models that accurately capture the complexities of GBM. Two-dimensional (2D) and three-dimensional (3D) cell culture models provide a versatile platform for studying NP-cell interactions. By customizing cell types, incorporating TME components, and adjusting flow conditions, researchers can tailor these models to specific research questions. While 2D models offer a simpler starting point, 3D models, such as multicellular spheroids and organoids, can more accurately replicate the complex TME, including the BBB and tumor heterogeneity. These models enable a more comprehensive evaluation of NP efficacy and safety, ultimately accelerating drug development and reducing reliance on animal testing.

Biomimetic Nanoparticle Based Targeted mRNA Vaccine Delivery as a Novel Therapy for Glioblastoma Multiforme

The prognosis for patients with glioblastoma multiforme (GBM), an aggressive and deadly brain tumor, is poor due to the limited therapeutic options available. Biomimetic nanoparticles have emerged as a promising vehicle for targeted mRNA vaccine delivery, thanks to recent advances in nanotechnology. This presents a novel treatment method for GBM. This review explores the potential of using biomimetic nanoparticles to improve the specificity and effectiveness of mRNA vaccine against GBM. These nanoparticles can evade immune detection, cross the blood-brain barrier, & deliver mRNA directly to glioma cells by mimicking natural biological structures. This allows glioma cells to produce tumor-specific antigens that trigger strong immune responses against the tumor. This review discusses biomimetic nanoparticle design strategies, which are critical for optimizing transport and ensuring targeted action. These tactics include surface functionalization and encapsulation techniques. It also highlights the ongoing preclinical research and clinical trials that demonstrate the therapeutic advantages and challenges of this strategy. Biomimetic nanoparticles for mRNA vaccine delivery represent a new frontier in GBM treatment, which could impact the management of this deadly disease and improve patient outcomes by integrating cutting-edge nanotechnology with immunotherapy.

Comprehensive insights into glioblastoma multiforme: drug delivery challenges and multimodal treatment strategies

Glioblastoma multiforme (GBM) is one of the most common and malignant brain tumors, with a high prevalence in elderly population. Most chemotherapeutic agents fail to reach the tumor site due to various challenges. However, smart nanocarriers have demonstrated excellent drug-loading capabilities, enabling them to cross the blood brain tumor barrier for the GBM treatment. Surface modification of nanocarriers has significantly enhanced their potential for targeting therapeutics. Moreover, recent innovations in drug therapies, such as the incorporation of theranostic agents in nanocarriers and antibody-drug conjugates, have offered newer insights for both diagnosis and treatment. This review focuses on recent advances in new therapeutic interventions for GBM, with an emphasis on the nanotheranostics systems to maximize therapeutic and diagnostic outcomes.

Comparison of Drug Delivery Systems with Different Types of Nanoparticles in Terms of Cellular Uptake and Responses in Human Endothelial Cells, Pericytes, and Astrocytes

Background/Objectives: The key components of the blood-brain barrier (BBB) are endothelial cells, pericytes, astrocytes, and the capillary basement membrane. The BBB serves as the main barrier for drug delivery to the brain and is the most restrictive endothelial barrier in the body. Nearly all large therapeutic molecules and over 90% of small-molecule drugs cannot cross the BBB. To overcome this challenge, nanotechnology, particularly drug delivery systems such as nanoparticles (NPs), have gained significant attention. Methods: Poly(lactide-co-glycolide) (PLGA) and albumin-based NPs (bovine/human), with or without transferrin (Tf) ligands (BSA, HSA, BSA-Tf, HSA-Tf), and nanolipid carriers (NLC) were synthesized. The interactions of these NPs with human brain microvascular endothelial cells (hBMECs), human brain vascular pericytes (hBVPs), and human astrocytes (hASTROs) were analyzed. Results: At doses of 15.62 µg/mL, 31.25 µg/mL, and 62.5 µg/mL, none of the NPs caused toxic effects on hBMECs, hBVPs, or hASTROs after 3 h of incubation. All NPs were internalized by the cells, but BSA-Tf and HSA-Tf showed significantly higher uptake in hBMECs in a dose-dependent manner. Ultrastructural analysis revealed notable differences between NP formulation and cell type. Conclusions: Our findings underscore the potential of ligand-targeted NPs to selectively interact with BBB endothelial cells. Ultrastructural analysis reveals distinct cellular processing pathways for various NP formulations across BBB-associated cell types, with autophagy emerging as a crucial mechanism for NP handling in pericytes and astrocytes. Changes in NP chemical properties upon biological exposure present significant challenges for nanomedicine design, emphasizing the need for further investigation into NP interactions at the cellular and subcellular levels.

Challenges of enzyme therapy: Why two players are better than one

Enzyme-based therapy has garnered significant attention for its current applications in various diseases. Despite the notable advantages associated with the use of enzymes as therapeutic agents, that could have high selectivity, affinity, and specificity for the target, their application faces challenges linked to physico-chemical and pharmacological properties. These limitations can be addressed through the encapsulation of enzymes in nanoplatforms as a comprehensive solution to mitigate their degradation, loss of activity, off-target accumulation, and immunogenicity, thus enhancing bioavailability, therapeutic efficacy, and circulation time, thereby reducing the number of administrations, and ameliorating patient compliance. The exploration of novel nanomedicine-based enzyme therapeutics for the treatment of challenging diseases stands as a paramount goal in the contemporary scientific landscape, but even then it is often not enough. Combining an enzyme with another therapeutic (e.g., a small molecule, another enzyme or protein, a monoclonal antibody, or a nucleic acid) within a single nanocarrier provides innovative multidrug-integrated therapy and ensures that both the actives arrive at the target site and exert their therapeutic effect, leading to synergistic action and superior therapeutic efficacy. Moreover, this strategic approach could be extended to gene therapy, a field that nowadays has gained increasing attention, as enzymes acting at genomic level and nucleic acids may be combined for synergistic therapy. This multicomponent therapeutic approach opens opportunities for promising future developments. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

Polymer-lipid hybrid nanomedicines to deliver siRNA in and against glioblastoma cells

Small interfering RNA (siRNA) holds great potential to treat many difficult-to-treat diseases, but its delivery remains the central challenge. This study aimed at investigating the suitability of polymer-lipid hybrid nanomedicines (HNMeds) as novel siRNA delivery platforms for locoregional therapy of glioblastoma. Two HNMed formulations were developed from poly(lactic-co-glycolic acid) polymer and a cationic lipid: 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol). After characterization of the HNMeds, a model siRNA was complexed onto their surface to form HNMed/siRNA complexes. The physicochemical properties and siRNA binding ability of complexes were assessed over a range of nitrogen-to-phosphate (N/P) ratios to optimize the formulations. At the optimal N/P ratio of 10, complexes effectively bound siRNA and improved its protection from enzymatic degradation. Using the NIH3T3 mouse fibroblast cell line, DOTAP-based HNMeds were shown to possess higher cytocompatibility in vitro over the DC-Chol-based ones. As proof-of-concept, uptake and bioefficacy of formulations were also assessed in vitro on U87MG human glioblastoma cell line expressing luciferase gene. Complexes were able to deliver anti-luciferase siRNA and induce a remarkable suppression of gene expression. Noteworthy, the effect of DOTAP-based formulation was not only about three-times higher than DC-Chol-based one, but also comparable to lipofectamine model transfection reagent. These findings set the basis to exploit this nanosystem for silencing relevant GB-related genes in further in vitro and in vivo studies.

"Combo" Multi-Target Pharmacological Therapy and New Formulations to Reduce Inflammation and Improve Endogenous Remyelination in Traumatic Spinal Cord Injury

Spinal cord injury (SCI) is characterized by a cascade of events that lead to sensory and motor disabilities. To date, this condition is irreversible, and no cure exists. To improve myelin repair and limit secondary degeneration, we developed a multitherapy based on nanomedicines (NMeds) loaded with the promyelinating agent triiodothyronine (T3), used in combination with systemic ibuprofen and mouse nerve growth factor (mNGF). Poly-L-lactic-co-glycolic acid (PLGA) NMeds were optimized and loaded with T3 to promote sustained release. In vitro experiments confirmed the efficacy of T3-NMeds to differentiate oligodendrocyte precursor cells. In vivo rat experiments were performed in contusion SCI to explore the NMed biodistribution and efficacy of combo drugs at short- and long-term post-lesion. A strong anti-inflammatory effect was observed in the short term with a reduction of type M1 microglia and glutamate levels, but with a subsequent increase of TREM2. In the long term, an improvement of myelination in NG2-IR, an increase in MBP content, and a reduction of the demyelination area were observed. These data demonstrated that NMeds can successfully be used to obtain more controlled local drug delivery and that this multiple treatment could be effective in improving the outcome of SCIs.

Recent Advances on Surface-Modified GBM Targeted Nanoparticles: Targeting Strategies and Surface Characterization

Glioblastoma multiforme (GBM) is the most common malignant brain tumor, associated with low long-term survival. Nanoparticles (NPs) developed against GBM are a promising strategy to improve current therapies, by enhancing the brain delivery of active molecules and reducing off-target effects. In particular, NPs hold high potential for the targeted delivery of chemotherapeutics both across the blood-brain barrier (BBB) and specifically to GBM cell receptors, pathways, or the tumor microenvironment (TME). In this review, the most recent strategies to deliver drugs to GBM are explored. The main focus is on how surface functionalizations are essential for BBB crossing and for tumor specific targeting. We give a critical analysis of the various ligand-based approaches that have been used to target specific cancer cell receptors and the TME, or to interfere with the signaling pathways of GBM. Despite the increasing application of NPs in the clinical setting, new methods for ligand and surface characterization are needed to optimize the synthesis, as well as to predict their in vivo behavior. An expert opinion is given on the future of this research and what is still missing to create and characterize a functional NP system for improved GBM targeting.

Optimization of an Injectable Hydrogel Depot System for the Controlled Release of Retinal-Targeted Hybrid Nanoparticles

A drawback in the development of treatments that can reach the retina is the presence of barriers in the eye that restrain compounds from reaching the target. Intravitreal injections hold promise for retinal delivery, but the natural defenses in the vitreous can rapidly degrade or eliminate therapeutic molecules. Injectable hydrogel implants, which act as a reservoir, can allow for long-term drug delivery with a single injection into the eye, but still suffer due to the fast clearance of the released drugs when traversing the vitreous and random diffusion that leads to lower pharmaceutic efficacy. A combination with HA-covered nanoparticles, which can be released from the gel and more readily pass through the vitreous to increase the delivery of therapeutic agents to the retina, represents an advanced and elegant way to overcome some of the limitations in eye drug delivery. In this article, we developed hybrid PLGA-Dotap NPs that, due to their hyaluronic acid coating, can improve in vivo distribution throughout the vitreous and delivery to retinal cells. Moreover, a hydrogel implant was developed to act as a depot for the hybrid NPs to better control and slow their release. These results are a first step to improve the treatment of retinal diseases by protecting and transporting the therapeutic treatment across the vitreous and to improve treatment options by creating a depot system for long-term treatments.

Hyaluronic Acid Scaffolds for Loco-Regional Therapy in Nervous System Related Disorders

Hyaluronic acid (HA) is a Glycosaminoglycan made of disaccharide units containing N-acetyl-D-glucosamine and glucuronic acid. Its molecular mass can reach 10 MDa and its physiological properties depend on its polymeric property, polyelectrolyte feature and viscous nature. HA is a ubiquitous compound found in almost all biological tissues and fluids. So far, HA grades are produced by biotechnology processes, while in the human organism it is a major component of the extracellular matrix (ECM) in brain tissue, synovial fluid, vitreous humor, cartilage and skin. Indeed, HA is capable of forming hydrogels, polymer crosslinked networks that are very hygroscopic. Based on these considerations, we propose an overview of HA-based scaffolds developed for brain cancer treatment, central and peripheral nervous systems, discuss their relevance and identify the most successful developed systems.