Design of Bio-Responsive Hyaluronic Acid-Doxorubicin Conjugates for the Local Treatment of Glioblastoma

Design strategies for hyaluronic acid-based drug delivery systems in cancer immunotherapy

Despite its robust therapeutic potential, cancer immunotherapy has provided little progress towards improved survival rates for patients bearing immunologically refractory tumors. The implementation of advanced drug delivery systems represents a powerful means of improving cancer immunotherapy by relieving immunosuppression and promoting immune response; however, the overall impact of these systems on immunotherapy currently remains modest. Hyaluronic acid represents a widely used polymer in drug delivery; meanwhile, recent studies linking hyaluronic acid to the immune system make this polymer an attractive component in the design of next-generation cancer immunotherapies. Herein, we review our current understanding of the immunological properties of hyaluronic acid and discuss them in the context of bioactive functions and immune-related interactions with receptors, immune, and cancer cells. We analyze the potential of hyaluronic acid as a component in advanced drug delivery systems, highlighting strategies for the design of more effective vaccines and cancer chemo-immunotherapies. Finally, we discuss critical considerations to facilitate design and clinical translation to overcome existing challenges and maximize therapeutic potential.

Repurposing Chemotherapeutics in a Hyaluronic Acid-conjugate Combination Treatment Approach for the Local Immunomodulation of the Glioblastoma Microenvironment

The immunosuppressive tumor immune microenvironment (TIME) renders glioblastoma (GBM) refractory to current chemo-immunotherapeutics. We sought to explore a novel approach for local GBM-associated TIME immunomodulation based on a synergistic combination of the repurposed chemotherapeutic drugs doxorubicin (DOX), which acts to induce immunogenic cell death (ICD) and gemcitabine (GEM), which depletes immunosuppressive myeloid-derived suppressor cells (MDSCs). We conjugated DOX and GEM to hyaluronic acid (HA) to improve efficacy, given this polymer's ability to target CD44 which are overexpressed on cancer cells. The HA-DOX and HA-GEM polymer-drug conjugates provided synergistic cytotoxic effects and maintained ICD-related properties in GBM cells compared to a combination of free drugs. HA-DOX and HA-GEM also reverted the immunosuppressive GBM-associated TIME in orthotopic GL261 tumor-bearing mice by selectively depleting MDSCs and reprogramming M2-like macrophages towards a pro-inflammatory M1-like state, resulting in controlled tumor growth. Local HA-DOX and HA-GEM delivery also increased median survival and controlled tumor growth in an immune refractory SB28-GBM orthotopic mouse GBM model. These findings highlight the potential of repurposing clinically applicable chemotherapeutics in the context of polymer-drug combination treatments for novel immunomodulation strategies in unresectable GBM, which may open new avenues for developing innovative therapies.

Hyaluronic acid-functionalized nanomedicines for CD44-receptors-mediated targeted cancer therapy: A review of selective targetability and biodistribution to tumor microenvironment

Cancer is a leading cause of death globally, driven by late diagnoses, aggressive progression, and multidrug resistance (MDR). Advances in nanotechnology are tackling these challenges, paving the way for transformative cancer treatments. Hyaluronic acid (HA)-based nanoparticles (NPs) have emerged as promising platforms due to their biocompatibility, biodegradability, and natural targeting capabilities via CD44 (cluster of differentiation 44) receptors. Functionalizing NPs with HA enhances cellular uptake through CD44, improves pharmacokinetics, tumor localization, and anticancer efficacy while reducing systemic toxicity. This review provides a comprehensive overview of HA-based NPs, highlighting their potential to address limitations in cancer treatment and inspire further innovation. The targeting efficiency of HA-based NPs can be further optimized by integrating passive (e.g., PEGylation), active (e.g., ligand conjugation), and stimuli-responsive mechanisms (e.g., pH, redox, light, enzyme activity, and temperature sensitivity). These NPs also enable therapeutic combinations, such as co-delivery of chemotherapeutics with gene therapies (e.g., siRNA) and integration of photothermal and photodynamic therapies, alongside immune checkpoint inhibitors, amplifying therapeutic synergy. Despite promising preclinical results, challenges such as scalability, stability, long-term safety, ethical and regulatory hurdles, and high costs persist. Nonetheless, HA-based NPs represent a cutting-edge approach, combining biocompatibility, precision targeting, and multimodal functionality to combat cancer effectively, while mitigating side effects.

Enhancing chemoimmunotherapy for colorectal cancer with paclitaxel and alantolactone via CD44-Targeted nanoparticles: A STAT3 signaling pathway modulation approach

Chemoimmunotherapy has the potential to enhance chemotherapy and modulate the immunosuppressive tumor microenvironment by activating immunogenic cell death (ICD), making it a promising strategy for clinical application. Alantolactone (A) was found to augment the anticancer efficacy of paclitaxel (P) at a molar ratio of 1:0.5 (P:A) through induction of more potent ICD via modulation of STAT3 signaling pathways. Nano drug delivery systems can synergistically combine natural drugs with conventional chemotherapeutic agents, thereby enhancing multi-drug chemoimmunotherapy. To improve tumor targeting ability and bioavailability of hydrophobic drugs, an amphiphilic prodrug conjugate (HA-PTX) was chemically modified with paclitaxel (PTX) and hyaluronic acid (HA) as a backbone. Based on this concept, CD44-targeted nanodrugs (A@HAP NPs) were developed for co-delivery of A and P in colorectal cancer treatment, aiming to achieve synergistic toxicity-based chemo-immunotherapy. The uniform size and high drug loading capacity of A@HAP NPs facilitated their accumulation within tumors through enhanced permeability and retention effect as well as HA-mediated targeting, providing a solid foundation for subsequent synergistic therapy and immunoregulation. In vitro and in vivo studies demonstrated that A@HAP NPs exhibited potent cytotoxicity against tumor cells while also remodeling the immune-suppressive tumor microenvironment by promoting antigen presentation and inducing dendritic cell maturation, thus offering a novel approach for colorectal cancer chemoimmunotherapy.

Advancing Therapeutic Strategies with Polymeric Drug Conjugates for Nucleic Acid Delivery and Treatment

The effective clinical translation of messenger RNA (mRNA), small interfering RNA (siRNA), and microRNA (miRNA) for therapeutic purposes hinges on the development of efficient delivery systems. Key challenges include their susceptibility to degradation, limited cellular uptake, and inefficient intracellular release. Polymeric drug conjugates (PDCs) offer a promising solution, combining the benefits of polymeric carriers and therapeutic agents for targeted delivery and treatment. This comprehensive review explores the clinical translation of nucleic acid therapeutics, focusing on polymeric drug conjugates. It investigates how these conjugates address delivery obstacles, enhance systemic circulation, reduce immunogenicity, and provide controlled release, improving safety profiles. The review delves into the conjugation strategies, preparation methods, and various classes of PDCs, as well as strategic design, highlighting their role in nucleic acid delivery. Applications of PDCs in treating diseases such as cancer, immune disorders, and fibrosis are also discussed. Despite significant advancements, challenges in clinical adoption persist. The review concludes with insights into future directions for this transformative technology, underscoring the potential of PDCs to advance nucleic acid-based therapies and combat infectious diseases significantly.

Carbohydrate polymer-driven nanoparticle synthesis and functionalization in the brain tumor therapy: A review

The brain tumors have been characterized with aggressive and heterogeneous nature. The treatment of brain tumors has been challenging due to their sensitive location and also, presence of blood-brain barrier (BBB) that reduces the entrance of bioactive compounds to the brain tissue. Therefore, the new treatment strategies should be focused on improving the efficacy of conventional therapeutics, crossing over biological barriers and introducing new kinds of methods for brain tumor elimination. In the recent years, the application of carbohydrate polymers in the treatment of human cancers has been increased as they possess biocompatibility, biodegradability and selective targeting of tumor cells. Moreover, carbohydrate polymer-based nanoparticles demonstrate desirable drug loading and encapsulation, making them suitable for the delivery of bioactive compounds. Accordingly, the carbohydrate polymers and their nanoparticles have been developed to improve the drug and gene delivery to brain tumors. Moreover, these nanoparticles can increase sensitivity of chemotherapy and immunotherapy. In addition to providing combination therapy, the carbohydrate polymer-based nanoparticles can elevate the phototherapy-mediated tumor ablation. These nanocarriers have demonstrated desirable particle size, zeta potential and encapsulation efficiency that are beneficial for brain tumor therapy. Moreover, these nanoparticles have high biocompatibility that can be subsequently utilized in clinical studies.

Doxorubicin-Loaded Ultrasmall Gold Nanoparticles (1.5 nm) for Brain Tumor Therapy and Assessment of Their Biodistribution

Ultrasmall gold nanoparticles (1.5 nm) were covalently conjugated with doxorubicin (AuDox) and AlexaFluor647 (AuAF647) to assess their biodistribution and their efficiency toward brain tumors (glioblastoma). A thorough characterization by transmission electron microscopy, small-angle X-ray scattering, and differential centrifugal sedimentation confirmed their uniform ultrasmall nature which makes them very mobile in the body. Each nanoparticle carried either 13 doxorubicin molecules (AuDox) or 2.7 AlexaFluor-647 molecules (AuAF647). The firm attachment of the ligands to the nanoparticles was demonstrated by their resilience to extensive washing, followed by centrifugation. The particles easily entered mammalian cells (HeLa, T98-G, brain endothelial cells, and human astrocytes) due to their small size. The intravenously delivered fluorescing AuAF647 nanoparticles crossed the blood-brain barrier with ∼23% accumulation in the brain tumor in an orthotopic U87 brain tumor model in nude mice. This was confirmed by elemental analysis (gold; inductively coupled plasma optical emission spectroscopy) in various organs. The doxorubicin-loaded AuDox nanoparticles inhibited brain tumor growth and prolonged animal survival without adverse side effects. Most of the nanoparticles (84%) had been excreted from the animal after 24 h, indicating a high mobility in the body.

Doxorubicin-loaded liposome-like particles embedded in chitosan/hyaluronic acid-based hydrogels as a controlled drug release model for local treatment of glioblastoma

Glioblastoma (GBM) resection and medication treatment are limited, and local drug therapies are required. This study aims to create a hybrid system comprising liposome-like particles (LLP-DOX) encapsulated in chitosan/hyaluronic acid/polyethyleneimine (CHI/HA/PEI) hydrogels, enabling controlled local delivery of doxorubicin (DOX) into the resection cavity for treating GBM. CHI/HA/PEI hydrogels were characterized morphologically, physically, chemically, mechanically, and thermally. Findings revealed a high network and compact micro-network structure, along with enhanced physical and thermal stability compared to CHI/HA hydrogels. Simultaneously, drug release from CHI/HA/PEI/LLP-DOX hydrogels was assessed, revealing continuous and controlled release up to the 148th hour, with no significant burst release. Cell studies showed that CHI/HA/PEI hydrogels are biocompatible with low genotoxicity. Additionally, LLP-DOX-loaded CHI/HA/PEI hydrogels significantly decreased cell viability and gene expression levels compared to LLP-DOX alone. It was also observed that the viability of GBM spheroids decreased over time when interacting with CHI/HA/PEI/LLP-DOX hydrogels, accompanied by a reduction in total surface area and an increase in apoptotic tendencies. In this study, we hypothesized that creating a hybrid drug delivery system by encapsulating DOX-loaded LLPs within a CHI/HA/PEI hydrogel matrix could achieve sustained drug release, improve anticancer efficacy via localized treatment, and effectively mitigate GBM progression for 3D microtissues.

In situ administration of STING-activating hyaluronic acid conjugate primes anti-glioblastoma immune response

Glioblastoma (GBM) is an aggressive brain tumor, with a highly immunosuppressive tumor immune microenvironment (TIME). In this work, we investigated the use of the STimulator of INterferon Genes (STING) pathway as an effective means to remodel the GBM TIME through the recruitment of both innate and adaptive immune cell populations. Using hyaluronic acid (HA), we developed a novel polymer-drug conjugate of a non-nucleotide STING agonist (MSA2), called HA-MSA2 for the in situ treatment of GBM. In JAWSII cells, HA-MSA2 exerted a greater increase of STING signaling and upregulation of STING-related downstream cyto-/chemokines in immune cells than the free drug. HA-MSA2 also elicited cancer cell-intrinsic immunostimulatory gene expression and promoted immunogenic cell death of GBM cells. In the SB28 GBM model, local delivery of HA-MSA2 induced a delay in tumor growth and a significant extension of survival. The analysis of the TIME showed a profound shift in the GBM immune landscape after HA-MSA2 treatment, with higher infiltration by innate and adaptive immune cells including dendritic, natural killer (NK) and CD8 T cell populations. The therapeutic potential of this novel polymer conjugate warrants further investigation, particularly with other chemo-immunotherapeutics or cancer vaccines as a promising combinatorial therapeutic approach.

The Application of Ultrasmall Gold Nanoparticles (2 nm) Functionalized with Doxorubicin in Three-Dimensional Normal and Glioblastoma Organoid Models of the Blood-Brain Barrier

Among brain tumors, glioblastoma (GBM) is very challenging to treat as chemotherapeutic drugs can only penetrate the brain to a limited extent due to the blood-brain barrier (BBB). Nanoparticles can be an attractive solution for the treatment of GBM as they can transport drugs across the BBB into the tumor. In this study, normal and GBM organoids comprising six brain cell types were developed and applied to study the uptake, BBB penetration, distribution, and efficacy of fluorescent, ultrasmall gold nanoparticles (AuTio-Dox-AF647s) conjugated with doxorubicin (Dox) and AlexaFluor-647-cadaverine (AF647) by confocal laser scanning microscopy (CLSM), using a mixture of dissolved doxorubicin and fluorescent AF647 molecules as a control. It was shown that the nanoparticles could easily penetrate the BBB and were found in normal and GBM organoids, while the dissolved Dox and AF647 molecules alone were unable to penetrate the BBB. Flow cytometry showed a reduction in glioblastoma cells after treatment with AuTio-Dox nanoparticles, as well as a higher uptake of these nanoparticles by GBM cells in the GBM model compared to astrocytes in the normal cell organoids. In summary, our results show that ultrasmall gold nanoparticles can serve as suitable carriers for the delivery of drugs into organoids to study BBB function.

Dual-targeting CD44 and mucin by hyaluronic acid and 5TR1 aptamer for epirubicin delivery into cancer cells: Synthesis, characterization, in vitro and in vivo evaluation

One of the revolutionized cancer treatment is active targeting nanomedicines. This study aims to create a dual-targeted drug delivery system for Epirubicin (EPI) to cancer cells. Hyaluronic acid (HA) is the first targeting ligand, and 5TR1 aptamer (5TR1) is the second targeting ligand to guide the dual-targeted drug delivery system to the cancer cells. HA is bound to highly expressed receptors like CD44 on cancer cells. 5TR1, DNA aptamer, is capable of recognizing MUC1 glycoprotein, which is overexpressed in cancer cells. The process involved binding EPI and 5TR1 to HA using adipic acid dihydrazide (AA) as a linker. The bond between the components was confirmed using 1H NMR. The binding of 5TR1 to HA-AA-EPI was confirmed using gel electrophoresis. The particle size (132.6 ± 9 nm) and Zeta Potential (-29 ± 4.4 mV) were measured for the final nanoformulation (HA-AA-EPI-5TR1). The release of EPI from the HA-AA-EPI-5TR1 nanoformulation was also studied at different pH levels. In the acidic pH (5.4 and 6.5) release pattern of EPI from the HA-AA-EPI-5TR1 nanoformulation was higher than physiological pH (7.4). The cytotoxicity and cellular uptake of the synthetic nanoformula were evaluated using MTT and flow cytometry analysis. Flow cytometry and cellular cytotoxicity studies were exhibited in a negative MUC1-cell line (CHO) and two positive MUC1+cell lines (MCF-7 and C26). Results confirmed that there is a notable contrast between the dual-targeted (HA-AA-EPI-5TR1) and single-targeted (HA-AA-EPI) nanoformulation in MCF-7 and C26 cell lines (MUC1+). In vivo studies showed that HA-AA-EPI-5TR1 nanoformulation has improved efficiency with limited side effect in C26 tumor-bearing mice. Also, Fluorescence imaging and pathological evaluation showed reduced side effects in the heart tissue of mice receiving HA-AA-EPI-5TR1 than free EPI. So, this targeted approach effectively delivers EPI to cancer cells with reduced side effects.

Combination nanochemotherapy of brain tumor using polymeric nanoparticles loaded with doxorubicin and paclitaxel: An in vitro and in vivo study

This study aims to overcome physiological barriers and increase the therapeutic index for the treatment of glioblastoma (GBM) tumors by using Paclitaxel (PTX) loaded Poly(lactic co-glycolic acid) nanoparticles (PTX-PLGA-NPs) and Doxorubicin (DOX) loaded Poly (lactic co-glycolic acid) nanoparticles (DOX-PLGA-NPs). The hydrodynamic diameter of nanoparticles (NPs) was characterized by dynamic light scattering (DLS) which was 94 ± 4 nm and 133 ± 6 nm for DOX-PLGA-NPs, and PTX-PLGA-NPs, respectively. The zeta potential for DOX-PLGA-NPs and PTX-PLGA-NPs were -15.2 ± 0.18 mV and -17.3 ± 0.34 mV, respectively. The cytotoxicity of PTX-PLGA-NPs and DOX-PLGA-NPs was augmented compared to DOX and PTX on C6 GBM cells. The Lactate dehydrogenase (LDH) tests for various formulations were carried out. The results indicated that the amount of released LDH was 262 ± 7.84 U.L-1 at the concentration of 2 mg/mL in the combination therapy, which was much higher than other groups (DOX-PLGA-NPs (210 ± 6.92 U.L-1), PTX-PLGA-NPs (201 ± 8.65 U.L-1), DOX (110 ± 9.81 U.L-1), PTX (95 ± 5.02 U.L-1) and PTX + DOX (67 ± 4.89 U.L-1)). MRI results of the combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs indicated that GBM tumor size decreased considerably compared to the other formulations. Also, combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs demonstrated a longer median survival of more than 80 days compared to PTX (38 days), DOX (37 days) and PTX + DOX (48 days), PTX-NPs (58 days) and DOX-NPs (62 days). The results of locomotion, body weight, rearing and grooming assays indicated that combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs had the most positive effect on the movements of rats compared to the other formulations.

Progressing nanotechnology to improve targeted cancer treatment: overcoming hurdles in its clinical implementation

The use of nanotechnology has the potential to revolutionize the detection and treatment of cancer. Developments in protein engineering and materials science have led to the emergence of new nanoscale targeting techniques, which offer renewed hope for cancer patients. While several nanocarriers for medicinal purposes have been approved for human trials, only a few have been authorized for clinical use in targeting cancer cells. In this review, we analyze some of the authorized formulations and discuss the challenges of translating findings from the lab to the clinic. This study highlights the various nanocarriers and compounds that can be used for selective tumor targeting and the inherent difficulties in cancer therapy. Nanotechnology provides a promising platform for improving cancer detection and treatment in the future, but further research is needed to overcome the current limitations in clinical translation.

Hyaluronic acid-antigens conjugates trigger potent immune response in both prophylactic and therapeutic immunization in a melanoma model

Immunotherapy of advanced melanoma has encountered significant hurdles in terms of clinical efficacy. Here, we designed a clinically translatable hyaluronic acid (HA)-based vaccine delivering a combination of major histocompatibility complex (MHC) class I- and class II-restricted melanoma antigens (TRP2 and Gp100, respectively) conjugated to HA. HA-nanovaccine (HA-TRP2-Gp100 conjugate) exhibited tropism in the lymph nodes and promoted stimulation of the immune response (2.3-fold higher than the HA+TRP2+Gp100). HA-nanovaccine significantly delayed the growth of B16F10 melanoma and extended survival in both the prophylactic and therapeutic settings (median survival of 22 and 27, respectively, vs 17 days of the untreated group). Moreover, mice prophylactically treated with the HA-nanovaccine displayed significantly higher CD8+ and CD4+ T-cell/Treg ratios in both the spleen and tumor at day 16, suggesting that the HA-nanovaccine overcame the immunosuppressive tumor microenvironment. Superior infiltration of active CD4+ and CD8+ T cells was observed at the endpoint. This study supports the conclusion that HA potentiates the effect of a combination of MHC I and MHC II antigens via a potent immune response against melanoma.

En route to local glioblastoma treatment with temozolomide doped hyaluronan fibres: formulation and in vitro cell studies

We report the preparation, characterisation and in vitro tests of hyaluronan fibres containing up to 50 w/w% of temozolomide for local glyoblastoma treatment. These fibres form a hydrogel upon contact with cerebrospinal fluid on the treatment spot.

Unravelling the Glioblastoma Tumour Microenvironment: Can Aptamer Targeted Delivery Become Successful in Treating Brain Cancers?

The key challenges to treating glioblastoma multiforme (GBM) are the heterogeneous and complex nature of the GBM tumour microenvironment (TME) and difficulty of drug delivery across the blood-brain barrier (BBB). The TME is composed of various neuronal and immune cells, as well as non-cellular components, including metabolic products, cellular interactions, and chemical compositions, all of which play a critical role in GBM development and therapeutic resistance. In this review, we aim to unravel the complexity of the GBM TME, evaluate current therapeutics targeting this microenvironment, and lastly identify potential targets and therapeutic delivery vehicles for the treatment of GBM. Specifically, we explore the potential of aptamer-targeted delivery as a successful approach to treating brain cancers. Aptamers have emerged as promising therapeutic drug delivery vehicles with the potential to cross the BBB and deliver payloads to GBM and brain metastases. By targeting specific ligands within the TME, aptamers could potentially improve treatment outcomes and overcome the challenges associated with larger therapies such as antibodies.

Combination of hyaluronic acid conjugates with immunogenic cell death inducer and CpG for glioblastoma local chemo-immunotherapy elicits an immune response and induces long-term survival

The efficacy of standard glioblastoma (GBM) treatments has been limited due to the highly immunosuppressive tumor immune microenvironment, interpatient tumor heterogenicity and anatomical barriers, such as the blood brain barrier. In the present work, we hypothesized that a new local therapy based on the combination of doxorubicin (DOX) as an immunogenic cell death (ICD) inducer and CpG, a Toll-like receptor (TLR)-9 agonist, would act synergistically to eradicate GBM. DOX and CpG were first tested in an orthotopic GL261 GBM model showing enhanced survival. To improve the outcome with a reduced dose, we designed bioresponsive hyaluronic acid (HA)-drug conjugates for effective in situ chemoimmunotherapy. HA was derivatized with CpG. The new HA-CpG conjugate showed high efficacy in re-educating protumoral M2-like microglia into an antitumoral M1-like phenotype, inducing the expression of immune-stimulatory cytokines. DOX was also conjugated to HA. DOX conjugation increased ICD induction in GL261 cells. Finally, a combination of the conjugates was explored in an orthotopic GL261 GBM model. The local delivery of combined HA-DOX + HA-CpG into the tumor mass elicited antitumor CD8⁺ T cell responses in the brain tumor microenvironment and reduced the infiltration of M2-like tumor-associated macrophages and myeloid-derived suppressor cells. Importantly, the combination of HA-DOX and HA-CpG induced long-term survival in >66% of GBM-bearing animals than other treatments (no long-term survivor observed), demonstrating the benefits of conjugating synergistic drugs to HA nanocarrier. These results emphasize that HA-drug conjugates constitute an effective drug delivery platform for local chemoimmunotherapy against GBM and open new perspectives for the treatment of other brain cancers and brain metastasis.

Recent advances in pH/enzyme-responsive polysaccharide-small-molecule drug conjugates as nanotherapeutics

Now-a-days, the polysaccharides are extensively employed for the delivery of small-molecule drugs ascribed to their excellent biocompatibility, biodegradability and modifiability. An array of drug molecules is often chemically conjugated with different polysaccharides to augment their bio-performances. As compared to their therapeutic precursors, these conjugates could typically demonstrate an improved intrinsic solubility, stability, bioavailability and pharmacokinetic profiles of the drugs. In current years, various stimuli-responsive particularly pH and enzyme-sensitive linkers or pendants are also exploited to integrate the drug molecules into the polysaccharide backbone. The resulting conjugates could experience a rapid molecular conformational change upon exposure to the microenvironmental pH and enzyme changes of the diseased states, triggering the release of the bioactive cargos at the targeted sites and eventually minimize the systemic side effects. Herein, the recent advances in pH and enzyme -responsive polysaccharide-drug conjugates and their therapeutic benefits are systematically reviewed, following a brief description on the conjugation chemistry of the polysaccharides and drug molecules. The challenges and future perspectives of these conjugates are also precisely discussed.

A peroxidase-like magneto-gold nanozyme AuNC@Fe3O4 with photothermal effect for induced cell apoptosis of hepatocellular carcinoma cells in vitro

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed and malignant cancers worldwide. Conventional therapy strategies may not completely eradicate the tumor and may cause side effects during treatment. Nano-catalytic therapy, as a novel strategy, has attracted a great deal of attention. This study aimed to synthesize a multifunctional magneto-gold nanozyme AuNC@Fe₃O₄ and evaluate its anti-cancer potential in HepG2 cells in vitro. The characteristics of AuNC@Fe₃O₄ were assessed using a transmission electron microscope, dynamic light scattering, and energy-dispersive X-ray. The photothermal performance and peroxidase (POD)-like activity of AuNC@Fe₃O₄ were detected, using thermal camera and ultraviolet-visible spectrophotometer, respectively. The anti-cancer potential of AuNC@Fe₃O₄ was examined using cell counting kit-8, live/dead cell staining, and apoptosis analysis. Further research on HepG2 cells included the detection of intracellular reactive oxygen species (ROS) and lysosomal impairment. We observed that the AuNC@Fe₃O₄ had a small size, good photothermal conversion efficiency and high POD-like activity, and also inhibited cell proliferation and enhanced cell apoptotic ability in HepG2 cells. Furthermore, the AuNC@Fe₃O₄ enhanced ROS production and lysosomal impairment via the synergistic effect of photothermal and nano-catalytic therapies, which induced cell death or apoptosis. Thus, the magneto-gold nanozyme AuNC@Fe₃O₄ may offer a potential anti-cancer strategy for HCC.

Synergistic effect of doxorubicin lauroyl hydrazone derivative delivered by α-tocopherol succinate micelles for the treatment of glioblastoma

We hypothesized that tocopherol succinate (TOS) and D-α-tocopherol polyethylene2000 succinate (TPGS₂₀₀₀) micelles could work as a drug delivery system while enhancing the anti-cancer efficacy of doxorubicin lauryl hydrazone derivative (DOXC₁₂) for the treatment of glioblastoma. The DOXC₁₂-TOS-TPGS₂₀₀₀ micelles were formulated with synthesized DOXC₁₂ and TPGS₂₀₀₀. They showed a high drug loading of hydrophobic DOXC₁₂ (29%), a size of <100 nm and a pH sensitive drug release behaviour. In vitro, fast uptake of DOXC₁₂-TOS-TPGS₂₀₀₀ micelles by GL261 cells was observed. For cytotoxicity, DOXC₁₂-TOS-TPGS₂₀₀₀ micelles were evaluated on two glioblastoma cell lines and showed synergism between DOXC₁₂ and TOS-TPGS_2000. The higher cytotoxicity of DOXC₁₂-TOS-TPGS₂₀₀₀ micelles was mainly caused by necrosis. The DOXC₁₂-TOS-TPGS₂₀₀₀ micelles seem to be a promising delivery system for enhancing the anticancer efficacy of doxorubicin in glioblastoma (GBM).

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.

Prostate Apoptosis Response-4 (Par-4): A Novel Target in Pyronaridine-Induced Apoptosis in Glioblastoma (GBM) Cells

Simple Summary

GBM treatment is an area of high unmet need due to the heterogeneous and anaplastic character of this cancer in turn leading to an extremely poor prognosis. Finding new molecular entities by traditional or de novo approaches to drug discovery is lengthy and expensive. Repurposing existing drugs can be attractive as the process is often less risky, more cost, and time-effective. Amongst potential drug-repurposing candidates, Pyronaridine (PYR), an antimalarial drug has shown anti-cancer effects against several cancers, however, its potential for the treatment of GBM has not been explored. In this study, we have identified a unique mechanism of action of PYR against GBM by upregulating a tumor suppressor protein, Par-4 along with the elucidation of the complex network of pathways mediated through Par-4 leading to GBM cell death.

Abstract

Glioblastoma (GBM) is an aggressive form of brain tumor with a median survival of approximately 12 months. With no new drugs in the last few decades and limited success in clinics for known therapies, drug repurposing is an attractive choice for its treatment. Here, we examined the efficacy of pyronaridine (PYR), an anti-malarial drug in GBM cells. PYR induced anti-proliferative activity in GBM cells with IC₅₀ ranging from 1.16 to 6.82 µM. Synergistic activity was observed when PYR was combined with Doxorubicin and Ritonavir. Mechanistically, PYR triggered mitochondrial membrane depolarization and enhanced the ROS levels causing caspase-3 mediated apoptosis. PYR significantly decreased markers associated with proliferation, EMT, hypoxia, and stemness and upregulated the expression of E-cadherin. Interestingly, PYR induced the expression of intracellular as well as secretory Par-4, a tumor suppressor in GBM cells, which was confirmed using siRNA. Notably, Par-4 levels in plasma samples of GBM patients were significantly lower than normal healthy volunteers. Thus, our study demonstrates for the first time that PYR can be repurposed against GBM with a novel mechanism of action involving Par-4. Herewith, we discuss the role of upregulated Par-4 in a highly interconnected signaling network thereby advocating its importance as a therapeutic target.

Construction of reduction-sensitive heterodimer prodrugs of doxorubicin and dihydroartemisinin self-assembled nanoparticles with antitumor activity

Doxorubicin (DOX) is used as a first-line chemotherapeutic drug, whereas dihydroartemisinin (DHA) also shows a certain degree of antitumor activity. Disulfide bonds (-SS-) in prodrug molecules can be degraded in highly reducing environments. Thus, heterodimer prodrugs of DOX and DHA linked by a disulfide bond was designed and subsequently prepared as reduction-responsive self-assembled nanoparticles (DOX-SS-DHA NPs). In an in vitro release study, DOX-SS-DHA NPs exhibited reduction-responsive activity. Upon cellular evaluation, DOX-SS-DHA NPs were found to have better selectivity toward tumor cells and less cytotoxicity to normal cells. Compared to free DiR, DOX-SS-DHA NPs showed improved accumulation at the tumor site and even had a longer clearance half-life. More importantly, DOX-SS-DHA NPs possessed a much higher tumor inhibition efficacy than DOX-sol and MIX-sol in 4T1 tumor-bearing mice. Our results suggested the superior antitumor efficacy of DOX-SS-DHA NPs with less cytotoxicity.

Hyaluronic Acid: Known for Almost a Century, but Still in Vogue

Hyaluronic acid (HA) has a special position among glycosaminoglycans. As a major component of the extracellular matrix (ECM). This simple, unbranched polysaccharide is involved in the regulation of various biological cell processes, whether under physiological conditions or in cases of cell damage. This review summarizes the history of this molecule's study, its distinctive metabolic pathway in the body, its unique properties, and current information regarding its interaction partners. Our main goal, however, is to intensively investigate whether this relatively simple polymer may find applications in protecting against ionizing radiation (IR) or for therapy in cases of radiation-induced damage. After exposure to IR, acute and belated damage develops in each tissue depending upon the dose received and the cellular composition of a given organ. A common feature of all organ damage is a distinct change in composition and structure of the ECM. In particular, the important role of HA was shown in lung tissue and the variability of this flexible molecule in the complex mechanism of radiation-induced lung injuries. Moreover, HA is also involved in intermediating cell behavior during morphogenesis and in tissue repair during inflammation, injury, and would healing. The possibility of using the HA polymer to affect or treat radiation tissue damage may point to the missing gaps in the responsible mechanisms in the onset of this disease. Therefore, in this article, we will also focus on obtaining answers from current knowledge and the results of studies as to whether hyaluronic acid can also find application in radiation science.

Fabrication and Modelling of a Reservoir-Based Drug Delivery System for Customizable Release

Localized therapy approaches have emerged as an alternative drug administration route to overcome the limitations of systemic therapies, such as the crossing of the blood–brain barrier in the case of brain tumor treatment. For this, implantable drug delivery systems (DDS) have been developed and extensively researched. However, to achieve an effective localized treatment, the release kinetics of DDS needs to be controlled in a defined manner, so that the concentration at the tumor site is within the therapeutic window. Thus, a DDS, with patient-specific release kinetics, is crucial for the improvement of therapy. Here, we present a computationally supported reservoir-based DDS (rDDS) development towards patient-specific release kinetics. The rDDS consists of a reservoir surrounded by a polydimethylsiloxane (PDMS) microchannel membrane. By tailoring the rDDS, in terms of membrane porosity, geometry, and drug concentration, the release profiles can be precisely adapted, with respect to the maximum concentration, release rate, and release time. The release is investigated using a model dye for varying parameters, leading to different distinct release profiles, with a maximum release of up to 60 days. Finally, a computational simulation, considering exemplary in vivo conditions (e.g., exchange of cerebrospinal fluid), is used to study the resulting drug release profiles, demonstrating the customizability of the system. The establishment of a computationally supported workflow, for development towards a patient-specific rDDS, in combination with the transfer to suitable drugs, could significantly improve the efficacy of localized therapy approaches.