Erythrocyte Membrane Cloaked Metal-Organic Framework Nanoparticle as Biomimetic Nanoreactor for Starvation-Activated Colon Cancer Therapy

Metal-organic frameworks: a biomimetic odyssey in cancer theranostics

This review comprehensively explores biomimetic metal-organic frameworks (MOFs) and their significant applications in cancer theranostics. Although MOFs have promising features such as adjustable porosity, improved surface area, and multifunctionality, they are limited by factors like low biocompatibility and specificity. Biomimetic strategies involving biological membranes and materials are proposed to address these challenges. The review begins by examining the unique characteristics and preparation methods of biomimetic carriers used in MOF-based nanoplatforms, with a comparative analysis of each method. It then delves into the various biomedical applications of biomimetic MOFs, including biosensing, bioimaging, immunotherapy, gene therapy, and multimodal therapies. The review also discusses the bio-interaction of these nanoplatforms, including their immunogenicity and interactions with fluids and tissues. Toxicity perspectives are also critically assessed. Overall, the article emphasizes the need for continued research into biomimetic MOFs, highlighting their potential to overcome current obstacles and provide safe, effective, and targeted therapeutic options.

Emerging glucose oxidase-delivering nanomedicines for enhanced tumor therapy

Abnormalities in glucose metabolism have been shown to characterize malignant tumors. Glucose depletion by glucose oxidase (GOD) has shown great potential in tumor therapy by causing tumor starvation. Since 2017, nanomedicines have been designed and utilized to deliver GOD for more precise and effective glucose modulation, which can overcome intrinsic limitations of different cancer therapeutic modalities by remodeling the tumor microenvironment to enhance antitumor therapy. To date, the topic of GOD-delivering nanomedicines for enhancing tumor therapy has not been comprehensively summarized. Herein, this review aims to provide an overview and discuss in detail recent advances in GOD delivery and directly involved starvation therapy strategies, GOD-sensitized various tumor therapy strategies, and GOD-mediated multimodal antitumor strategies. Finally, the challenges and outlooks for the future progress of the emerging tumor therapeutic nanomedicines are discussed. This review provides intuitive and specific insights to a broad audience in the fields of nanomedicines, biomaterials, and cancer therapy.

Anticancer effects of silymarin-loaded ACA-HA/sulfonamide IR-MOF nanoplatform in CT-26 xenograft model

Silymarin, a herbal compound with antioxidant and anti-inflammatory properties, has shown potential in inhibiting colon cancer cell growth. However, its clinical application is hindered by poor bioavailability. This study introduces a novel metal-organic framework, Sul-IRMOF, modified with 6-aminocaproic acid (ACA) and hyaluronic acid (HA) to create Sul-IRMOF-ACA-HA, which enables targeted drug delivery via HA receptors. Histological staining, biochemical analyses, and flow cytometry revealed that Sul-IRMOF-ACA-HA@Sily significantly enhances cytotoxicity against CT-26 cells compared to pure silymarin. According to oxidative stress markers, Sul-IRMOF-ACA-HA@Sily significantly reduced total thiol and glutathione (GSH) content compared to the control (p < 0.001) and silymarin (p < 0.001). Catalase (CAT) and superoxide dismutase (SOD) activities were significantly reduced in all treatment groups (p < 0.001), with Sul-IRMOF-ACA-HA@Sily showing the most pronounced effects (p < 0.001 vs. silymarin). Additionally, malondialdehyde (MDA) and nitric oxide (NO) levels were significantly elevated in the silymarin and Sul-IRMOF-ACA-HA@Sily groups compared to the control (p < 0.001), with Sul-IRMOF-ACA-HA@Sily further increasing both markers compared to silymarin (p < 0.001). The synergistic design of ACA, HA, and Sul-IRMOF offers a promising strategy to overcome silymarin's bioavailability limitations, positioning Sul-IRMOF-ACA-HA@Sily as a novel therapeutic candidate for colorectal cancer.

Erythrocyte membrane vesicles as drug delivery systems: A systematic review of preclinical studies on biodistribution and pharmacokinetics

This systematic review aims to summarize the development of erythrocyte membrane vesicles (EMVs) as drug delivery carriers, with a focus on elucidating their fate in terms of biodistribution and pharmacokinetics in preclinical studies. The PubMed database was systematically reviewed to search for original peer-reviewed published studies on the use of EMVs for drug delivery to summarize the preclinical findings, following the PRISMA guidelines. A total of 142 articles matched the selection criteria and were included in the review. For each study, the following parameters were extracted: type of active pharmaceutical ingredient (API) encapsulated into EMVs, EMVs-API formulation method and final particle size, EMVs surface modifications for active targeting, cell lines and animal models used in the study, crucial treatment data, biodistribution data and finally, where applicable, data about the EMVs circulation time and blood half-life. EMVs size did not vary significantly among the different formulation methods. A complete list of cell lines and animal models used is provided. Circulation times and data for blood half-life were grouped per animal type. For the most commonly used animal type, BALB/c mice, the average half-life of EMV-API was calculated to be 10.4 h, and in all cases, up to a 10-fold increase was observed compared with that of free API. Surface modifications did not drastically change the circulation time but did improve target tissue accumulation. The most critical weaknesses in the analysed studies were identified. Key points for future studies are provided to fill the current knowledge gaps and improve the quality of publications.

Diversified nanocarrier design to optimize glucose oxidase-mediated anti-tumor therapy: Strategy and progress

Given the inherent complexity and heterogeneity of tumors, current therapeutic approaches often fall short in meeting prognostic requirements. Starvation therapy (ST) utilizing glucose oxidase (GOx) has emerged as a promising strategy, specifically targeting tumor glucose consumption to disrupt nutrient supply. However, the therapeutic potential of GOx is significantly hampered by its inherent limitations as a protein, particularly its poor stability and short in vivo half-life. In recent years, the development of nanocarriors has provided an effective platform for intravenous and local tumor delivery of GOx. This review systematically examines three key strategies in GOx delivery: stimulus-response, biofilm modification, and local delivery. The progress in various carrier systems for GOx-mediated tumor therapy is comprehensively summarized, providing valuable insights for nanocarrier design. Furthermore, the existing challenges and future directions to advance the development of GOx-based tumor therapies are critically analyzed.

Reduced graphene oxide quantum dots/manganese dioxide/glucose oxidase nanoparticles for cascade catalytic cancer treatment in multimodal starvation therapy-augmented chemodynamic/photothermal therapy

Combination cancer therapy can boost the overall treatment efficacy using functional nanomaterials that specifically target cancer cells. Furthermore, the treatment outcome can be improved by focusing on specific characteristics in the tumor microenvironment (TME). In this study, tumor-targeting multifunctional nanoparticles were constructed from reduced graphene oxide quantum dots (rGOQD), manganese dioxide (MnO2), glucose oxidase (GOx), and cell-penetrating peptide (CPP). The rGOQD/MnO2/GOx/CPP nanoparticles can treat tumors by strengthening chemodynamic/photothermal therapy (CDT/PTT) with starvation therapy (ST). The MnO2 reacts with high concentrations of endogenous H2O2 in an acidic TME to produce reactive oxygen species (ROSs) from Mn2+. The highly cytotoxic hydroxyl radical (•OH) kills cancer cells and initiates CDT. The MnO2 can also consume the •OH scavenger glutathione (GSH) in cancer cells and eliminate their antioxidant defense. The GOx oxidizes glucose to cause cancer cell glucose starvation for ST, which produces H2O2 to boost the efficacy of CDT. By consuming glucose, ST mediated by GOx leads to reduced ATP production in the glycolysis pathway. This downregulates the expression of ATP-dependent heat shock proteins that provide cancer cell thermal resistance when the photothermal agent rGOQD is irradiated with near-infrared (NIR) light for PTT. Therefore, we prepare different rGOQD-based nanoparticles and characterize their physicochemical and biological properties. The nanoparticles were studied in vitro against U87 glioblastoma cells for targeted cancer therapy. Using nude mice bearing subcutaneous U87 tumors, the in vivo study indicates rGOQD/MnO2/GOx/CPP plus NIR irradiation can substantially inhibit the tumor growth rate without causing adverse effects from CPP-mediated trimodal ST/CDT/PTT.

Bimetallic peroxide-based nanotherapeutics for immunometabolic intervention and induction of immunogenic cell death to augment cancer immunotherapy

Immunotherapy has transformed cancer treatment, but its efficacy is often limited by the immunosuppressive characteristics of the tumor microenvironment (TME), which are predominantly influenced by the metabolism of cancer cells. Among these metabolic pathways, the indoleamine 2,3-dioxygenase (IDO) pathway is particularly crucial, as it significantly contributes to TME suppression and influences immune cell activity. Additionally, inducing immunogenic cell death (ICD) in tumor cells can reverse the immunosuppressive TME, thereby enhancing the efficacy of immunotherapy. Herein, we develop CGDMRR, a novel bimetallic peroxide-based nanodrug based on copper-cerium peroxide nanoparticles. These nanotherapeutics are engineered to mitigate tumor hypoxia and deliver therapeutics such as 1-methyltryptophan (1MT), glucose oxidase (GOx), and doxorubicin (Dox) in a targeted manner. The design aims to alleviate tumor hypoxia, reduce the immunosuppressive effects of the IDO pathway, and promote ICD. CGDMRR effectively inhibits the growth of 4T1 tumors and elicits antitumor immune responses by leveraging immunometabolic interventions and therapies that induce ICD. Furthermore, when CGDMRR is combined with a clinically certified anti-PD-L1 antibody, its efficacy in inhibiting tumor growth is enhanced. This improved efficacy extends beyond unilateral tumor models, also affecting bilateral tumors and lung metastases, due to the activation of systemic antitumor immunity. This study underscores CGDMRR's potential to augment the efficacy of PD-L1 blockade in breast cancer immunotherapy.

Engineered cell membrane-cloaked metal-organic framework nanocrystals for intracellular cargo delivery

This investigation demonstrates the development and functionality of cell membrane-cloaked UiO-67 nanosized metal-organic frameworks (NMOFs), which are engineered for precise intracellular delivery of encapsulated cargoes. Utilizing the robust and porous nature of UiO-67, we enveloped these NMOFs with fusogenic cell membrane-derived nanovesicles (FCSMs) sourced from adenocarcinomic human alveolar basal epithelial (A549) cells. This biomimetic coating enhances biocompatibility and leverages the homotypic targeting capabilities of the cell-derived coatings, facilitating direct cytoplasmic delivery and avoiding endolysosomal entrapment. Our nanoplatform exhibited high efficiency in loading and releasing two model cargoes: cresyl violet (CV), a staining agent, and carboplatin (CbPt), a chemotherapeutic agent. This approach demonstrated substantial potential in drug delivery in both 2D cell cultures and 3D spheroids. This study underscores the enhanced cellular uptake facilitated by the engineered biomimetic shell and highlights the system's capacity for sustained release, offering a promising strategy for targeted drug delivery.

Metal-organic framework-based smart stimuli-responsive drug delivery systems for cancer therapy: advances, challenges, and future perspectives

Cancer treatment is currently one of the most critical healthcare issues globally. A well-designed drug delivery system can precisely target tumor tissues, improve efficacy, and reduce damage to normal tissues. Stimuli-responsive drug delivery systems (SRDDSs) have shown promising application prospects. Intelligent nano drug delivery systems responsive to endogenous stimuli such as weak acidity, complex redox characteristics, hypoxia, active energy metabolism, as well as exogenous stimuli like high temperature, light, pressure, and magnetic fields are increasingly being applied in chemotherapy, radiotherapy, photothermal therapy, photodynamic therapy, and various other anticancer approaches. Metal-organic frameworks (MOFs) have become promising candidate materials for constructing SRDDSs due to their large surface area, tunable porosity and structure, ease of synthesis and modification, and good biocompatibility. This paper reviews the application of MOF-based SRDDSs in various modes of cancer therapy. It summarizes the key aspects, including the classification, synthesis, modifications, drug loading modes, stimuli-responsive mechanisms, and their roles in different cancer treatment modalities. Furthermore, we address the current challenges and summarize the potential applications of artificial intelligence in MOF synthesis. Finally, we propose strategies to enhance the efficacy and safety of MOF-based SRDDSs, ultimately aiming at facilitating their clinical translation.

Tumor-Homing Biomimetic Near-Infrared II SERS Probes for Targeted Intraoperative Resection Guidance of Orthotopic Glioblastoma

In vivo optical imaging holds great potential for surgical guidance with the ability to intraoperatively identify tumor lesions in a surgical bed and navigate their surgical excision in real time. Nevertheless, its full potential remains underexploited, mainly due to the dearth of high-performance optical probes. Herein, hybrid cell membrane-biomimetic near-infrared II surface-enhanced Raman spectroscopy (NIR-II SERS) probes are reported for intraoperative resection guidance of orthotopic glioblastoma. A novel class of plasmonic Au nanorod (AuNR)@Au-Ag frames is developed with remarkable plasmonic properties tunable beyond 1700 nm. We demonstrate the exceptional NIR-II SERS performance both in vitro and in vivo of the biomimetic NIR-II SERS probes created with AuNR@Au-Ag frames and hybrid cell membranes. The biomimetic NIR-II SERS probes are successfully applied in an orthotopic glioblastoma mouse model for intraoperative resection guidance with complete tumor removal and improved surgical outcomes. This study presents a promising strategy for precise NIR-II SERS surgical navigation.

Iron-glucose oxidase nanogel assembly for amplified starvation-ferroptosis anti-tumor therapy

Developing advanced and effective enzyme-drug systems for cancer treatment is of significant interest. Herein, a novel approach is reported to create a highly active and robust enzyme-drug system. Glucose oxidase nanogels (nGOx) are first synthesized by polymerization on the surface of GOx using vinylimidazole as comonomers. Fe3+ are utilized to induce self-assembly of nGOx through the imidazole-metal coordination interaction to form GOx nanogel clusters (Fe@nGOx), enhancing the permeability and retention of nGOx into tumor cells by EPR effect. nGOx can deplete glucose in the presence of oxygen and generate H2O2, which is converted to highly cytotoxic hydroxyl radical (·OH) by Fe3+ and GSH, and the proximity between Fe3+ and GOx act in tandem for enhanced tumor therapy. The FeIII/FeII redox cycle reacts with GSH and H2O2, enabling continuous generation of ·OH within tumor cells, thus facilitating the anticancer effect. Moreover, the generation of H2O2 and ·OH can further promote the repolarization of tumor-associated macrophages from an M2 phenotype towards an M1 phenotype polarization, thus enhancing immune response. The cascade reaction between GOx and Fe3+/Fe2+ endows Fe@nGOx with excellent anti-tumor efficacy in mice models, highlighting its potential as a promising anticancer drug for clinical applications. This work establishes a new platform for utilizing enzyme/protein and metal ion complexes in versatile applications, advancing the field of enzyme-based cancer therapies.

Recent advances in zeolitic imidazolate frameworks as drug delivery systems for cancer therapy

Biological nanotechnologies based on functional nanoplatforms have synergistically catalyzed the emergence of cancer therapies. As a subtype of metal-organic frameworks (MOFs), zeolitic imidazolate frameworks (ZIFs) have exploded in popularity in the field of biomaterials as excellent protective materials with the advantages of conformational flexibility, thermal and chemical stability, and functional controllability. With these superior properties, the applications of ZIF-based materials in combination with various therapies for cancer treatment have grown rapidly in recent years, showing remarkable achievements and great potential. This review elucidates the recent advancements in the use of ZIFs as drug delivery agents for cancer therapy. The structures, synthesis methods, properties, and various modifiers of ZIFs used in oncotherapy are presented. Recent advances in the application of ZIF-based nanoparticles as single or combination tumor treatments are reviewed. Furthermore, the future prospects, potential limitations, and challenges of the application of ZIF-based nanomaterials in cancer treatment are discussed. We except to fully explore the potential of ZIF-based materials to present a clear outline for their application as an effective cancer treatment to help them achieve early clinical application.

Self-Boosting Programmable Release of Multiple Therapeutic Agents by Activatable Heterodimeric Prodrug-Enzyme Assembly for Antitumor Therapy

Endogenous stimuli-responsive prodrugs, due to their disease lesion specificity and reduced systemic toxicity, have been widely explored for antitumor therapy. However, reactive oxygen species (ROS) as classical endogenous stimuli in the tumor microenvironment (TME) are not enough to achieve the expected drug release. Herein, a ROS-activatable heterodimeric prodrug-loaded enzyme assembly is developed for self-boosting programmable release of multiple therapeutic agents. The heterodimeric prodrug NBS-TK-PTX (namely NTP) is composed of 5-(ethylamino)-9-diethylaminobenzo[a]phenothiazinium chloride analog (NBS), paclitaxel (PTX) and ROS-responsive thioketal (TK) linker, which shows a strong binding affinity with glucose oxidase (GOx), thus obtaining NTP@GOx assembly. Notably, the enzymatic activity of GOx in NTP@GOx is inhibited by NTP. The programmable release is achieved by following steps: i) NTP@GOx is partially dissociated in acidic TME, thus releasing a small segment of NTP and GOx. Thereupon, the enzymatic activity of GOx is recovered; ii) GOx-triggered pH reduction further facilitates the dissociation of NTP@GOx, thus accelerating a large amount of NTP and GOx release; iii) The TK linker of prodrug NTP is cleaved by hydrogen peroxide generated by GOx catalysis, thus expediting the release of NBS for Type-I photodynamic therapy and PTX for chemotherapy, respectively. The NTP@GOx shows great potential for multimodal synergistic cancer therapy.

Focused starvation of tumor cells using glucose oxidase: A comprehensive review

Starvation therapy targets the high metabolic demand of tumor cells. It primarily leans over the consumption of intracellular glucose and simultaneous blockade of alternative metabolic pathways. The strategy involves the use of glucose oxidase (GOx) for catalyzing the conversion of glucose into gluconic acid and hydrogen peroxide. Under these conditions, metabolic re-programming of tumor cells enables the utilization of substrates such as amino acids, fatty acids and lipids. This can be overcome by co-administration of chemo-, photo- and immuno-therapeutics together with glucose oxidase. Targeted delivery of glucose oxidase at tumor site can be enabled with the use of nanoformulations. In this review, we highlight that the outcomes of starvation therapy can be improved using rationally developed nano-formulations. It is possible to load synergistically acting bioactives in these formulations and deliver in site-specific manner and hence achieve the elimination of tumors cells with greater efficacy.

Gene-Engineered Cerium-Exosomes Mediate Atherosclerosis Therapy Through Remodeling of the Inflammatory Microenvironment and DNA Damage Repair

The pro-inflammatory immune microenvironment in the localized lesion areas and the absence of DNA damage repair mechanisms in endothelial cells serve as essential accelerating factors in the development of atherosclerosis. The lack of targeted therapeutic strategies represents a significant limitation in the efficacy of therapeutic agents for atherosclerosis. In this study, Genetically engineered SNHG12-loaded cerium-macrophage exosomes (Ce-Exo) are designed as atherosclerosis-targeting agents. In vivo studies demonstrated that Ce-Exo exhibited multivalent targeting properties for macrophages, with a 4.1-fold higher atherosclerotic plaque-aggregation ability than that of the control drugs. This suggests that Ce-Exo has a higher homing capacity and deeper penetration into the atherosclerotic plaque. In apolipoprotein E-deficient mice, Ce-Exo found to effectively remodel the immune microenvironment in the lesion area, repair endothelial cell damage, and inhibit the development of atherosclerosis. This study provides a novel approach to the treatment of atherosclerosis and demonstrates the potential of cell-derived drug carriers in biomedicine.

Nano- and Micro-Platforms in Therapeutic Proteins Delivery for Cancer Therapy: Materials and Strategies

Proteins have emerged as promising therapeutics in oncology due to their great specificity. Many treatment strategies are developed based on protein biologics, such as immunotherapy, starvation therapy, and pro-apoptosis therapy, while some protein biologics have entered the clinics. However, clinical translation is severely impeded by instability, short circulation time, poor transmembrane transportation, and immunogenicity. Micro- and nano-particles-based drug delivery platforms are designed to solve those problems and enhance protein therapeutic efficacy. This review first summarizes the different types of therapeutic proteins in clinical and research stages, highlighting their administration limitations. Next, various types of micro- and nano-particles are described to demonstrate how they can overcome those limitations. The potential of micro- and nano-particles are then explored to enhance the therapeutic efficacy of proteins by combinational therapies. Finally, the challenges and future directions of protein biologics carriers are discussed for optimized protein delivery.

A Nanoreactor Based on Metal-Organic Frameworks With Triple Synergistic Therapy for Hepatocellular Carcinoma

The transformation of monotherapy into multimodal combined targeted therapy to fully exploit synergistic efficacy is of increasing interest in tumor treatment. In this work, a novel nanodrug-carrying platform based on iron-based MOFs, which is loaded with doxorubicin hydrochloride (DOX), dihydroartemisinin (DHA), and glucose oxidase (GOx), and concurrently covalently linked to the photosensitizer 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) in polydopamine (PDA)-encapsulated MIL-101(Fe) (denoted as MIL-101(Fe)-DOX-DHA@TCPP/GOx@PDA, MDDTG@P), is successfully developed. Upon entering the tumor microenvironment, MDDTG@P catalyzes the hydrogen peroxide (H2O2) into hydroxyl radicals (·OH) and depletes glutathione (GSH); thus, exerting the role of chemodynamic therapy (CDT). The reduced Fe2+ can also activate DHA, further expanding CDT and promoting tumor cell apoptosis. The introduced GOx will rapidly consume glucose and oxygen (O2) in the tumor; while, replenishing H2O2 for Fenton reaction, starving the cancer cells; and thus, realizing starvation and chemodynamic therapy. In addition, the covalent linkage of TCPP endows MDDTG@P with good photodynamic therapeutic (PDT) properties. Therefore, this study develops a nanocarrier platform for triple synergistic chemodynamic/photodynamic/starvation therapy, which has promising applications in the efficient treatment of tumors.

Exploring enzyme-immobilized MOFs and their application potential: biosensing, biocatalysis, targeted drug delivery and cancer therapy

Enzymes are indispensable in several applications including biosensing and degradation of pollutants and in the drug industry. However, adverse conditions restrict enzymes' utility in biocatalysis due to their inherent limitations. Metal-organic frameworks (MOFs), with their robust structure, offer an innovative avenue for enzyme immobilization, enhancing their resilience against harsh solvents and temperatures. This advancement is pivotal for application in bio-sensing, bio-catalysis, and specifically, targeted drug delivery in cancer therapy, where enzyme-MOF composites enable precise therapeutic localization, minimizing the side effects of traditional treatment. The adaptable nature of MOFs enhances drug biocompatibility and availability, significantly improving therapeutic outcomes. Moreover, the integration of enzyme-immobilized MOFs into bio-sensing represents a leap forward in the rapid and accurate identification of biomarkers, facilitating early diagnosis and disease monitoring. In bio-catalysis, this synergy promotes efficient and environmentally safe chemical synthesis, enhancing reaction rates and yields and broadening the scope of enzyme application in pharmaceutical and bio-fuel production. This review article explores the immobilization techniques and their biomedical applications, specifically focusing on drug delivery in cancer therapy and bio-sensing. Additionally, it addresses the challenges faced in this expanding field.

Advances in multifunctional metal-organic framework (MOF)-based nanoplatforms for cancer starvation therapy

Cancer remains a significant threat to human health today. Even though starvation therapy and other treatment methods have recently advanced to a new level of rapid development in tumour treatment, their limited therapeutic effectiveness and unexpected side effects prevent them from becoming the first option in clinical treatment. With rapid advancement in nanotechnology, the utilization of nanomaterials in therapeutics offers the potential to address the shortcomings in cancer treatment. Notably, multifunctional metal-organic framework (MOF) has been widely employed in cancer therapy due to their customizable shape, adjustable diameter, high porosity, diverse compositions, large specific surface area, high degree of functionalization and strong biocompatibility. This paper reviews the current progress and success of MOF-based multifunctional nanoplatforms for cancer starvation therapy, as well as the prospects and potential barriers for the application of MOF nanoplatforms in cancer starvation therapy.

Tailored Metal-Based Catalysts: A New Platform for Targeted Anticancer Therapies

Innovative strategies for targeted anticancer therapies have gained significant momentum, with metal complexes emerging as tunable catalysts for more effective and safer treatments. Rational design and engineering of metal complexes enable the development of tailored molecular structures optimized for precision oncology. The strategic incorporation of metal complex catalysts within combinatorial therapies amplifies their anticancer properties. This perspective highlights the advancements in synthetic strategies and rational design since 2019, showing how tailored metal catalysts are optimized by designing structures to release or in situ synthesize active drugs, leveraging the target-specific characteristics to develop more precise cancer therapies. This review explores metal-based catalysts, including those conjugated with biomolecules, nanostructures, and metal-organic frameworks (MOFs), highlighting their catalytic activity in biological environments and their in vitro/in vivo performance. To sum up, the potential of metal complexes as catalysts to reshape the landscape of anticancer therapies and foster novel avenues for therapeutic advancement is emphasized.

Current status and prospects of MOFs loaded with H2O2-related substances for ferroptosis therapy

Ferroptosis is a programmed cell death mechanism characterized by the accumulation of iron (Fe)-dependent lipid peroxides within cells. Ferroptosis holds excellent promise in tumor therapy. Metal-organic frameworks (MOFs) offer unique advantages in tumor ferroptosis treatment due to their high porosity, excellent stability, high biocompatibility, and targeting capabilities. Inducing ferroptosis in tumor cells primarily involves the production of reactive oxygen species (ROS), like hydroxyl radicals (˙OH), through iron-mediated Fenton reactions. However, the intrinsic H2O2 levels in tumor cells are often insufficient to sustain prolonged consumption, limiting therapeutic efficacy if ˙OH production is inadequate. Therefore, catalyzing or supplementing the intracellular H2O2 levels in tumor cells is essential for inducing ferroptosis by nanoscale metal-organic frameworks. This article reviews the biological characteristics and molecular mechanisms of ferroptosis, introduces H2O2-related substances, and reviews MOF-based nanoscale strategies for enhancing intracellular H2O2 levels in tumor cells. Finally, the challenges and prospects of this approach are discussed, aiming to provide insights into improving the effectiveness of ferroptosis induced by MOFs.

Cell Membrane-Coated Nanoparticles for Dental, Oral, and Craniofacial Diseases

Dental, oral, and craniofacial diseases can substantially impact the quality of human life, thereby posing a serious public health concern. Although conventional therapies such as surgery have solved these problems largely, the prognosis of patients is not always satisfactory. Cell membrane-coated nanoparticles (CMCNPs) carry nanodrugs with the help of natural cell membranes, therefore utilizing their remarkable ability to interface and interact with their surrounding environment. These nanoparticles have demonstrated substantial advantages in drug targeting, prolonging blood circulation time, penetrating biofilms, and immune escape. With the assistance of CMCNPs, the therapeutic effects of dental, oral, and craniofacial diseases can reach a higher level. CMCNPs have been applied for dental, oral, and craniofacial diseases for various conditions such as head and neck cancer, periodontal disease, and oral biosignal detection. For the therapies of head and neck cancer, CMCNPs have been widely utilized as a tool of chemotherapy, phototherapy, and immunotherapy, while yet to be exploited in imaging technique. In the end, we summarized the challenges and prospectives of CMCNPs for dental, oral, and craniofacial diseases: large-scale production with uniform standards and high quantity, extensive application directions in dental, oral, and craniofacial regions (implant, endodontics), and the promotion of its clinical application.

Biomimetic Iron-Based Nanoparticles Remodel Immunosuppressive Tumor Microenvironment for Metabolic Immunotherapy

Introduction

Immunotherapy has led to a paradigm shift in reinvigorating treatment of cancer. Nevertheless, tumor associated macrophages (TAMs) experience functional polarization on account of the generation of suppressive metabolites, contributing to impaired antitumor immune responses.

Methods

Hence, metabolic reprogramming of tumor microenvironment (TME) can synergistically improve the efficacy of anti-tumor immunotherapy. Herein, we engineered an iron-based nanoplatform termed ERFe3O4 NPs. This platform features hollow Fe3O4 nanoparticles loaded with the natural product emodin, the outer layer is coated with red blood cell membrane (mRBCs) inserted with DSPE-PEG2000-galactose. This effectively modulates lactate production, thereby reversing the tumor immune suppressive microenvironment (TIME).

Results

The ERFe3O4 NPs actively targeted TAMs on account of their ability to bind to M2-like TAMs with high expression of galectin (Mgl). ERFe3O4 NPs achieved efficient ability to reverse TIME via the production of reducing lactate and prompting enrichment iron of high concentrations. Furthermore, ERFe3O4 NPs resulted in heightened expression of CD16/32 and enhanced TNF-α release, indicating promotion of M1 TAMs polarization. In vitro and in vivo experiments revealed that ERFe3O4 NPs induced significant apoptosis of tumor cells and antitumor immune response.

Discussion

This study combines Traditional Chinese Medicine (TCM) with nanomaterials to synergistically reprogram TAMs and reverse TIME, opening up new ideas for improving anti-tumor immunotherapy.

Hollow CeO2-Based Nanozyme with Self-Accelerated Cascade Reactions for Combined Tumor Therapy

Nanozymes have obvious advantages in improving the efficiency of cancer treatment. However, due to the lack of tissue specificity, low catalytic efficiency, and so on, their clinical applications are limited. Herein, the nanoplatform CeO2@ICG@GOx@HA (CIGH) with self-accelerated cascade reactions is constructed. The as-prepared nanozyme shows the superior oxidase (OXD)-like, superoxide dismutase (SOD)-like, catalase (CAT)-like and peroxidase (POD)-like activities. At the same time, under 808 nm near-infrared (NIR) irradiation, the photodynamic and photothermal capabilities are also significantly enhanced due to the presence of indocyanine green (ICG). We demonstrate that the nanozyme CIGH can efficiently accumulate in the tumor and exhibit amplified cascade antitumor effects with negligible systemic toxicity through the combination of photodynamic therapy (PDT), photothermal therapy (PTT), chemodynamic therapy (CDT) and starvation therapy. The nanozyme prepared in this study provides a promising candidate for catalytic nanomedicines for efficient tumor therapy.

Catalytic Nanoparticles in Biomedical Applications: Exploiting Advanced Nanozymes for Therapeutics and Diagnostics

Catalytic nanoparticles (CNPs) as heterogeneous catalyst reveals superior activity due to their physio-chemical features, such as high surface-to-volume ratio and unique optical, electric, and magnetic properties. The CNPs, based on their physio-chemical nature, can either increase the reactive oxygen species (ROS) level for tumor and antibacterial therapy or eliminate the ROS for cytoprotection, anti-inflammation, and anti-aging. In addition, the catalytic activity of nanozymes can specifically trigger a specific reaction accompanied by the optical feature change, presenting the feasibility of biosensor and bioimaging applications. Undoubtedly, CNPs play a pivotal role in pushing the evolution of technologies in medical and clinical fields, and advanced strategies and nanomaterials rely on the input of chemical experts to develop. Herein, a systematic and comprehensive review of the challenges and recent development of CNPs for biomedical applications is presented from the viewpoint of advanced nanomaterial with unique catalytic activity and additional functions. Furthermore, the biosafety issue of applying biodegradable and non-biodegradable nanozymes and future perspectives are critically discussed to guide a promising direction in developing span-new nanozymes and more intelligent strategies for overcoming the current clinical limitations.

Current advance of nanotechnology in diagnosis and treatment for malignant tumors

Cancer remains a significant risk to human health. Nanomedicine is a new multidisciplinary field that is garnering a lot of interest and investigation. Nanomedicine shows great potential for cancer diagnosis and treatment. Specifically engineered nanoparticles can be employed as contrast agents in cancer diagnostics to enable high sensitivity and high-resolution tumor detection by imaging examinations. Novel approaches for tumor labeling and detection are also made possible by the use of nanoprobes and nanobiosensors. The achievement of targeted medication delivery in cancer therapy can be accomplished through the rational design and manufacture of nanodrug carriers. Nanoparticles have the capability to effectively transport medications or gene fragments to tumor tissues via passive or active targeting processes, thus enhancing treatment outcomes while minimizing harm to healthy tissues. Simultaneously, nanoparticles can be employed in the context of radiation sensitization and photothermal therapy to enhance the therapeutic efficacy of malignant tumors. This review presents a literature overview and summary of how nanotechnology is used in the diagnosis and treatment of malignant tumors. According to oncological diseases originating from different systems of the body and combining the pathophysiological features of cancers at different sites, we review the most recent developments in nanotechnology applications. Finally, we briefly discuss the prospects and challenges of nanotechnology in cancer.

Opportunities for nanomaterials in enzyme therapy

In recent years, enzyme therapy strategies have rapidly evolved to catalyze essential biochemical reactions with therapeutic potential. These approaches hold particular promise in addressing rare genetic disorders, cancer treatment, neurodegenerative conditions, wound healing, inflammation management, and infectious disease control, among others. There are several primary reasons for the utilization of enzymes as therapeutics: their substrate specificity, their biological compatibility, and their ability to generate a high number of product molecules per enzyme unit. These features have encouraged their application in enzyme replacement therapy where the enzyme serves as the therapeutic agent to rectify abnormal metabolic and physiological processes, enzyme prodrug therapy where the enzyme initiates a clinical effect by activating prodrugs, and enzyme dynamic or starving therapy where the enzyme acts upon host substrate molecules. Currently, there are >20 commercialized products based on therapeutic enzymes, but approval rates are considerably lower than other biologicals. This has stimulated nanobiotechnology in the last years to develop nanoparticle-based solutions that integrate therapeutic enzymes. This approach aims to enhance stability, prevent rapid clearance, reduce immunogenicity, and even enable spatio-temporal activation of the therapeutic catalyst. This comprehensive review delves into emerging trends in the application of therapeutic enzymes, with a particular emphasis on the synergistic opportunities presented by incorporating enzymes into nanomaterials. Such integration holds the promise of enhancing existing therapies or even paving the way for innovative nanotherapeutic approaches.

Effective strategies to enhance the diagnosis and treatment of RCC: The application of biocompatible materials

Renal cell carcinoma (RCC) is recognized as one of the three primary malignant tumors affecting the urinary system, posing a significant risk to human health and life. Despite advancements in understanding RCC, challenges persist in its diagnosis and treatment, particularly in early detection and diagnosis due to issues of low specificity and sensitivity. Consequently, there is an urgent need for the development of effective strategies to enhance diagnostic accuracy and treatment outcomes for RCC. In recent years, with the extensive research on materials for applications in the biomedical field, some materials have been identified as promising for clinical applications, e.g., in the diagnosis and treatment of many tumors, including RCC. Herein, we summarize the latest materials that are being studied and have been applied in the early diagnosis and treatment of RCC. While focusing on their adjuvant effects, we also discuss their technical principles and safety, thus highlighting the value and potential of their application. In addition, we also discuss the limitations of the application of these materials and possible future directions, providing new insights for improving RCC diagnosis and treatment.

High-performance self-cascade nanoreactors for combined ferroptosis, photothermal therapy, and starving therapy

Despite the great potential of starving therapy caused by nanoreactor based on glucose oxidase (GOX) in tumor therapy, efficiency and uncontrolled reaction rates in vivo lead to inevitable toxicity to normal tissues, which seriously hindering their clinical conversion. Herein, a cascade nanoreactor (GOX/Mn/MPDA) was constructed by coating mesoporous polydopamine nanoparticles (MPDA) with MnO2 shell and then depositing GOX into honeycomb-shaped manganese oxide nanostructures to achieve a combination of ferroptosis, photothermal therapy and starving therapy. Upon uptake of nanodrugs to cancer cells, the MnO2 shell would deplete glutathione (GSH) and produce Mn2+, while a large amount of H2O2 generated from the catalytic oxidation of glucose by GOX would accelerate the Fenton-like reaction mediated by Mn2+, producing high toxic •OH. More importantly, the cascade reaction between GOX and MnO2 would be further strengthened by localized hyperthermia caused by irradiated by near-infrared laser (NIR), inducing significant anti-tumor effects in vitro and in vivo. Regarding the effectiveness of tumor treatment in vivo, the tumor inhibition rate achieved an impressive 64.33%. This study provided a new strategy for anti-tumor therapeutic by designing a photothermal-enhanced cascade catalytic nanoreactor.

Biomimetic Hydrogel Strategies for Cancer Therapy

Recent developments in biomimetic hydrogel research have expanded the scope of biomedical technologies that can be used to model, diagnose, and treat a wide range of medical conditions. Cancer presents one of the most intractable challenges in this arena due to the surreptitious mechanisms that it employs to evade detection and treatment. In order to address these challenges, biomimetic design principles can be adapted to beat cancer at its own game. Biomimetic design strategies are inspired by natural biological systems and offer promising opportunities for developing life-changing methods to model, detect, diagnose, treat, and cure various types of static and metastatic cancers. In particular, focusing on the cellular and subcellular phenomena that serve as fundamental drivers for the peculiar behavioral traits of cancer can provide rich insights into eradicating cancer in all of its manifestations. This review highlights promising developments in biomimetic nanocomposite hydrogels that contribute to cancer therapies via enhanced drug delivery strategies and modeling cancer mechanobiology phenomena in relation to metastasis and synergistic sensing systems. Creative efforts to amplify biomimetic design research to advance the development of more effective cancer therapies will be discussed in alignment with international collaborative goals to cure cancer.

Nanoparticles as Drug Delivery Systems for the Targeted Treatment of Atherosclerosis

Atherosclerosis continues to be a leading cause of morbidity and mortality globally. The precise evaluation of the extent of an atherosclerotic plaque is essential for forecasting its likelihood of causing health concerns and tracking treatment outcomes. When compared to conventional methods used, nanoparticles offer clear benefits and excellent development opportunities for the detection and characterisation of susceptible atherosclerotic plaques. In this review, we analyse the recent advancements of nanoparticles as theranostics in the management of atherosclerosis, with an emphasis on applications in drug delivery. Furthermore, the main issues that must be resolved in order to advance clinical utility and future developments of NP research are discussed. It is anticipated that medical NPs will develop into complex and advanced next-generation nanobotics that can carry out a variety of functions in the bloodstream.

Metal organic framework-based polymeric hydrogel: A promising drug delivery vehicle for the treatment of breast cancer

The constraints associated with current cancer therapies have inspired scientists to develop advanced, precise, and safe drug delivery methods. These delivery systems boost treatment effectiveness, minimize harm to healthy cells, and combat cancer recurrence. To design advanced drug delivery vehicle with these character, in the present manuscript, we have designed a self-healing and injectable hybrid hydrogel through synergistically interacting metal organic framework, CuBTC with the poly(vinyl alcohol) (PVA). This hybrid hydrogel acts as a localized drug delivery system and was used to encapsulate and release the anticancer drug 5-Fluorouracil selectively at the targeted site in response to the physiological pH. The hydrogel was formed through transforming the gaussian coil like matrix of PVA-CuBTC into a three-dimensional network of hydrogel upon the addition of crosslinker; borax. The biocompatible character of the hydrogel was confirmed through cell viability test. The biocompatible hybrid hydrogel then was used to encapsulate and studied for the pH responsive release behavior of the anti-cancer drug, 5-FU. The in vitro cytotoxicity of the drug-loaded hydrogel was evaluated against MCF-7 and HeLa cells. The study confirms that the hybrid hydrogel is effective for targeted and sustained release of anticancer drugs at cancer sites.

Facile Synthesis of a Multifunctional Porous Organic Polymer Nanosonosensitizer (mHM@HMME) for Enhanced Cancer Sonodynamic Therapy

Sonodynamic therapy (SDT), which involves the activation of sonosensitizers to generate cytotoxic reactive oxygen species under ultrasound irradiation, is a promising noninvasive modality for cancer treatment. However, the clinical translational application of SDT is impeded by the lack of efficient sonosensitizers, the inefficient accumulation of sonosensitizers at tumor sites, and the complicated immunosuppressive tumor microenvironment. Herein, we developed a facilely synthesized multifunctional porous organic polymer nanosonosensitizer (mHM@HMME) for enhanced SDT. Specifically, mHM@HMME nanosonosensitizers were prepared by incorporating chemotherapeutic mitoxantrone into the one-step synthesis process of disulfide bond containing porous organic polymers, followed by loading with organic sonosensitizer (HMME) and camouflaging with a cancer cell membrane. Due to the cancer cell membrane camouflage, this multifunctional mHM@HMME nanosonosensitizer showed prolonged blood circulation and tumor targeting aggregation. Under ultrasound irradiation, the mHM@HMME nanosonosensitizer exhibited a satisfactory SDT performance both in vitro and in vivo. Moreover, the potent SDT combined with glutathione-responsive drug release in tumor cells induced robust immunogenic cell death to enhance the antitumor effect of SDT in turn. Overall, this facilely synthesized multifunctional mHM@HMME nanosonosensitizer shows great potential application in enhanced SDT.

Engineering Nanoplatforms for Theranostics of Atherosclerotic Plaques

Atherosclerotic plaque formation is considered the primary pathological mechanism underlying atherosclerotic cardiovascular diseases, leading to severe cardiovascular events such as stroke, acute coronary syndromes, and even sudden cardiac death. Early detection and timely intervention of plaques are challenging due to the lack of typical symptoms in the initial stages. Therefore, precise early detection and intervention play a crucial role in risk stratification of atherosclerotic plaques and achieving favorable post-interventional outcomes. The continuously advancing nanoplatforms have demonstrated numerous advantages including high signal-to-noise ratio, enhanced bioavailability, and specific targeting capabilities for imaging agents and therapeutic drugs, enabling effective visualization and management of atherosclerotic plaques. Motivated by these superior properties, various noninvasive imaging modalities for early recognition of plaques in the preliminary stage of atherosclerosis are comprehensively summarized. Additionally, several therapeutic strategies are proposed to enhance the efficacy of treating atherosclerotic plaques. Finally, existing challenges and promising prospects for accelerating clinical translation of nanoplatform-based molecular imaging and therapy for atherosclerotic plaques are discussed. In conclusion, this review provides an insightful perspective on the diagnosis and therapy of atherosclerotic plaques.

Enzyme hybrid nanoflowers and enzyme@metal-organic frameworks composites: fascinating hybrid nanobiocatalysts

Hybrid nanomaterials have recently emerged as a new interface of nanobiocatalysis, serving as a host platform for enzyme immobilization. Enzyme immobilization in inorganic crystal nanoflowers and metal-organic frameworks (MOFs) has sparked the bulk of scientific interest due to their superior performances. Many breakthroughs have been achieved recently in the preparation of various types of enzyme@MOF and enzyme-hybrid nanoflower composites. However, it is unfortunate that there are few reviews in the literature related to enzyme@MOF and enzyme-hybrid nanoflower composites and their improved synthesis strategies and their applications in biotechnology. In this review, innovative synthetic strategies for enzyme@MOF composites and enzyme-hybrid nanoflower composites are discussed. Enzyme@MOF composites and enzyme-hybrid nanoflower composites are reviewed in terms of biotechnological applications and potential research directions. We are convinced that a fundamental study and application of enzyme@MOF composites and enzyme-hybrid nanoflower composites will be understood by the reader as a result of this work. The summary of different synthetic strategies for enzyme@MOF composites and enzyme-hybrid nanoflower composites and the improvement of their synthetic strategies will also benefit the readers and provide ideas and thoughts in the future research process.

Biochemical hallmarks-targeting antineoplastic nanotherapeutics

Tumor microenvironments (TMEs) have received increasing attention in recent years as they play pivotal roles in tumorigenesis, progression, metastases, and resistance to the traditional modalities of cancer therapy like chemotherapy. With the rapid development of nanotechnology, effective antineoplastic nanotherapeutics targeting the aberrant hallmarks of TMEs have been proposed. The appropriate design and fabrication endow nanomedicines with the abilities for active targeting, TMEs-responsiveness, and optimization of physicochemical properties of tumors, thereby overcoming transport barriers and significantly improving antineoplastic therapeutic benefits. This review begins with the origins and characteristics of TMEs and discusses the latest strategies for modulating the TMEs by focusing on the regulation of biochemical microenvironments, such as tumor acidosis, hypoxia, and dysregulated metabolism. Finally, this review summarizes the challenges in the development of smart anti-cancer nanotherapeutics for TME modulation and examines the promising strategies for combination therapies with traditional treatments for further clinical translation.

Advancing stroke therapy: the potential of MOF-based nanozymes in biomedical applications

In this study, we explored the growing use of metal-organic framework (MOF)-based Nanozymes in biomedical research, with a specific emphasis on their applications in stroke therapy. We have discussed the complex nature of stroke pathophysiology, highlighting the crucial role of reactive oxygen species (ROS), and acknowledging the limitations of natural enzymes in addressing these challenges. We have also discussed the role of nanozymes, particularly those based on MOFs, their structural similarities to natural enzymes, and their potential to improve reactivity in various biomedical applications. The categorization of MOF nanozymes based on enzyme-mimicking activities is discussed, and their applications in stroke therapy are explored. We have reported the potential of MOF in treating stroke by regulating ROS levels, alleviation inflammation, and reducing neuron apoptosis. Additionally, we have addressed the challenges in developing efficient antioxidant nanozyme systems for stroke treatment. The review concludes with the promise of addressing these challenges and highlights the promising future of MOF nanozymes in diverse medical applications, particularly in the field of stroke treatment.

A biomimetic camouflaged metal organic framework for enhanced siRNA delivery in the tumor environment

Gene silencing through RNA interference (RNAi), particularly using small double-stranded RNA (siRNA), has been identified as a potent strategy for targeted cancer treatment. Yet, its application faces challenges such as nuclease degradation, inefficient cellular uptake, endosomal entrapment, off-target effects, and immune responses, which have hindered its effective delivery. In the past few years, these challenges have been addressed significantly by using camouflaged metal-organic framework (MOF) nanocarriers. These nanocarriers protect siRNA from degradation, enhance cellular uptake, and reduce unintended side effects by effectively targeting desired cells while evading immune detection. By combining the properties of biomimetic membranes and MOFs, these nanocarriers offer superior benefits such as extended circulation times, enhanced stability, and reduced immune responses. Moreover, through ligand-receptor interactions, biomimetic membrane-coated MOFs achieve homologous targeting, minimizing off-target adverse effects. The MOFs, acting as the core, efficiently encapsulate and protect siRNA molecules, while the biomimetic membrane-coated surface provides homologous targeting, further increasing the precision of siRNA delivery to cancer cells. In particular, the biomimetic membranes help to shield the MOFs from the immune system, avoiding unwanted immune responses and improving their biocompatibility. The combination of siRNA with innovative nanocarriers, such as camouflaged-MOFs, presents a significant advancement in cancer therapy. The ability to deliver siRNA with precision and effectiveness using these camouflaged nanocarriers holds great promise for achieving more personalized and efficient cancer treatments in the future. This review article discusses the significant progress made in the development of siRNA therapeutics for cancer, focusing on their effective delivery through novel nanocarriers, with a particular emphasis on the role of metal-organic frameworks (MOFs) as camouflaged nanocarriers.

Boosting Enzyme Activity in Enzyme Metal-Organic Framework Composites

Enzymes, as highly efficient biocatalysts, excel in catalyzing diverse reactions with exceptional activity and selective properties under mild conditions. Nonetheless, their broad applications are hindered by their inherent fragility, including low thermal stability, limited pH tolerance, and sensitivity to organic solvents and denaturants. Encapsulating enzymes within metal-organic frameworks (MOFs) can protect them from denaturation in these harsh environments. However, this often leads to a compromised enzyme activity. In recent years, extensive research efforts have been dedicated to enhancing enzymatic activity within MOFs, leading to the development of new enzyme-MOF composites that not only preserve their catalytic potential but also outperform their free counterparts. This Review provides a comprehensive review on recent developments in enzyme-MOF composites with a specific emphasis on their enhanced enzymatic activity compared to free enzymes.

Intelligent Delivery Systems in Tumor Metabolism Regulation: Exploring the Path Ahead

Cancer metabolism plays multifaceted roles in the initiation and progression of tumors, and interventions in metabolism are considered fundamental approaches for cancer control. Within the vast metabolic networks of tumors, there exist numerous potential therapeutic targets, intricately interconnected with each other and with signaling networks related to immunity, metastasis, drug resistance, and more. Based on the characteristics of the tumor microenvironment, constructing drug delivery systems for multi-level modulation of the tumor microenvironment is proven as an effective strategy for achieving multidimensional control of cancer. Consequently, this article summarizes several features of tumor metabolism to provide insights into recent advancements in intelligent drug delivery systems for achieving multi-level regulation of the metabolic microenvironment in cancer, with the aim of offering a novel paradigm for cancer treatment.

Biomedical application of metal-organic frameworks (MOFs) in cancer therapy: Stimuli-responsive and biomimetic nanocomposites in targeted delivery, phototherapy and diagnosis

The nanotechnology is an interdisciplinary field that has become a hot topic in cancer therapy. Metal-organic frameworks (MOFs) are porous materials and hybrid composites consisted of organic linkers and metal cations. Despite the wide application of MOFs in other fields, the potential of MOFs for purpose of cancer therapy has been revealed by the recent studies. High surface area and porosity, significant drug loading and encapsulation efficiency are among the benefits of using MOFs in drug delivery. MOFs can deliver genes/drugs with selective targeting of tumor cells that can be achieved through functionalization with ligands. The photosensitizers and photo-responsive nanostructures including carbon dots and gold nanoparticles can be loaded in/on MOFs to cause phototherapy-mediated tumor ablation. The immunogenic cell death induction and increased infiltration of cytotoxic CD8+ and CD4+ T cells can be accelerated by MOF platforms in providing immunotherapy of tumor cells. The stimuli-responsive MOF platforms responsive to pH, redox, enzyme and ion can accelerate release of therapeutics in tumor site. Moreover, MOF nanocomposites can be modified ligands and green polymers to improve their selectivity and biocompatibility for cancer therapy. The application of MOFs for the detection of cancer-related biomarkers can participate in the early diagnosis of patients.

Current advances in modulating tumor hypoxia for enhanced therapeutic efficacy

Hypoxia is a common feature of most solid tumors, which promotes the proliferation, invasion, metastasis, and therapeutic resistance of tumors. Researchers have been developing advanced strategies and nanoplatforms to modulate tumor hypoxia to enhance therapeutic effects. A timely review of this rapidly developing research topic is therefore highly desirable. For this purpose, this review first introduces the impact of hypoxia on tumor development and therapeutic resistance in detail. Current developments in the construction of various nanoplatforms to enhance tumor treatment in response to hypoxia are also systematically summarized, including hypoxia-overcoming, hypoxia-exploiting, and hypoxia-disregarding strategies. We provide a detailed discussion of the rationale and research progress of these strategies. Through a review of current trends, it is hoped that this comprehensive overview can provide new prospects for clinical application in tumor treatment. STATEMENT OF SIGNIFICANCE: As a common feature of most solid tumors, hypoxia significantly promotes tumor progression. Advanced nanoplatforms have been developed to modulate tumor hypoxia to enhanced therapeutic effects. In this review, we first introduce the impact of hypoxia on tumor progression. Current developments in the construction of various nanoplatforms to enhance tumor treatment in response to hypoxia are systematically summarized, including hypoxia-overcoming, hypoxia-exploiting, and hypoxia-disregarding strategies. We discuss the rationale and research progress of the above strategies in detail, and finally introduce future challenges for treatment of hypoxic tumors. By reviewing the current trends, this comprehensive overview can provide new prospects for clinical translatable tumor therapy.

Recent advances in metal-organic frameworks for stimuli-responsive drug delivery

After entering the human body, drugs for treating diseases, which are prone to delivery and release in an uncontrolled manner, are affected by various factors. Based on this, many researchers utilize various microenvironmental changes encountered during drug delivery to trigger drug release and have proposed stimuli-responsive drug delivery systems. In recent years, metal-organic frameworks (MOFs) have become promising stimuli-responsive agents to release the loaded therapeutic agents at the target site to achieve more precise drug delivery due to their high drug loading, excellent biocompatibility, and high stimuli-responsiveness. The MOF-based stimuli-responsive systems can respond to various stimuli under pathological conditions at the site of the lesion, releasing the loaded therapeutic agent in a controlled manner, and improving the accuracy and safety of drug delivery. Due to the changes in different physical and chemical factors in the pathological process of diseases, the construction of stimuli-responsive systems based on MOFs has become a new direction in drug delivery and controlled release. Based on the background of the rapidly increasing attention to MOFs applied in drug delivery, we aim to review various MOF-based stimuli-responsive drug delivery systems and their response mechanisms to various stimuli. In addition, the current challenges and future perspectives of MOF-based stimuli-responsive drug delivery systems are also discussed in this review.

A critical review on metal-organic frameworks (MOFs) based nanomaterials for biomedical applications: Designing, recent trends, challenges, and prospects

Nanomaterials (NMs) have garnered significant attention in recent decades due to their versatile applications in a wide range of fields. Thanks to their tiny size, enhanced surface modifications, impressive volume-to-surface area ratio, magnetic properties, and customized optical dispersion. NMs experienced an incredible upsurge in biomedical applications including diagnostics, therapeutics, and drug delivery. This minireview will focus on notable examples of NMs that tackle important issues, demonstrating various aspects such as their design, synthesis, morphology, classification, and use in cutting-edge applications. Furthermore, we have classified and outlined the distinctive characteristics of the advanced NMs as nanoscale particles and hybrid NMs. Meanwhile, we emphasize the incredible potential of metal-organic frameworks (MOFs), a highly versatile group of NMs. These MOFs have gained recognition as promising candidates for a wide range of bio-applications, including bioimaging, biosensing, antiviral therapy, anticancer therapy, nanomedicines, theranostics, immunotherapy, photodynamic therapy, photothermal therapy, gene therapy, and drug delivery. Although advanced NMs have shown great potential in the biomedical field, their use in clinical applications is still limited by issues such as stability, cytotoxicity, biocompatibility, and health concerns. This review article provides a thorough analysis offering valuable insights for researchers investigating to explore new design, development, and expansion opportunities. Remarkably, we ponder the prospects of NMs and nanocomposites in conjunction with current technology.

In-situ-sprayed therapeutic hydrogel for oxygen-actuated Janus regulation of postsurgical tumor recurrence/metastasis and wound healing

Surgery is the mainstay of treatment modality for malignant melanoma. However, the deteriorative hypoxic microenvironment after surgery is recognized as a stemming cause for tumor recurrence/metastasis and delayed wound healing. Here we design and construct a sprayable therapeutic hydrogel (HIL@Z/P/H) encapsulating tumor-targeted nanodrug and photosynthetic cyanobacteria (PCC 7942) to prevent tumor recurrence/metastasis while promote wound healing. In a postsurgical B16F10 melanoma model in female mice, the nanodrug can disrupt cellular redox homeostasis via the photodynamic therapy-induced cascade reactions within tumor cells. Besides, the photosynthetically generated O2 by PCC 7942 can not only potentiate the oxidative stress-triggered cell death to prevent local recurrence of residual tumor cells, but also block the signaling pathway of hypoxia-inducible factor 1α to inhibit their distant metastasis. Furthermore, the long-lasting O2 supply and PCC 7942-secreted extracellular vesicles can jointly promote angiogenesis and accelerate the wound healing process. Taken together, the developed HIL@Z/P/H capable of preventing tumor recurrence/metastasis while promoting wound healing shows great application potential for postsurgical cancer therapy.

Biomimetic Nano-Drug Delivery System: An Emerging Platform for Promoting Tumor Treatment

With the development of nanotechnology, nanoparticles (NPs) have shown broad prospects as drug delivery vehicles. However, they exhibit certain limitations, including low biocompatibility, poor physiological stability, rapid clearance from the body, and nonspecific targeting, which have hampered their clinical application. Therefore, the development of novel drug delivery systems with improved biocompatibility and high target specificity remains a major challenge. In recent years, biofilm mediated biomimetic nano-drug delivery system (BNDDS) has become a research hotspot focus in the field of life sciences. This new biomimetic platform uses bio-nanotechnology to encapsulate synthetic NPswithin biomimetic membrane, organically integrating the low immunogenicity, low toxicity, high tumor targeting, good biocompatibility of the biofilm with the adjustability and versatility of the nanocarrier, and shows promising applications in the field of precision tumor therapy. In this review, we systematically summarize the new progress in BNDDS used for optimizing drug delivery, providing a theoretical reference for optimizing drug delivery and designing safe and efficient treatment strategies to improve tumor treatment outcomes.

Hypoxia and Singlet Oxygen Dual-Responsive Micelles for Photodynamic and Chemotherapy Therapy Featured with Enhanced Cellular Uptake and Triggered Cargo Delivery

Introduction

Combination therapy provides better outcomes than a single therapy and becomes an efficient strategy for cancer treatment. In this study, we designed a hypoxia- and singlet oxygen-responsive polymeric micelles which contain azo and nitroimidazole groups for enhanced cellular uptake, repaid cargo release, and codelivery of photosensitizer Ce6 and hypoxia-activated prodrug tirapazamine TPZ (DHM-Ce6@TPZ), which could be used for combining Ce6-mediated photodynamic therapy (PDT) and PDT-activated chemotherapy to enhance the therapy effect of cancer.

Methods

The hypoxia- and singlet oxygen-responsive polymeric micelles DHM-Ce6@TPZ were prepared by film hydration method. The morphology, physicochemical properties, stimuli responsiveness, in vitro singlet oxygen production, cellular uptake, and cell viability were evaluated. In addition, the in vivo therapeutic effects of the micelles were verified using a tumor xenograft mice model.

Results

The resulting dual-responsive micelles not only increased the concentration of intracellular photosensitizer and TPZ, but also facilitated photosensitizer and TPZ release for enhanced integration of photodynamic and chemotherapy therapy. As a photosensitizer, Ce6 induced PDT by generating toxic singlet reactive oxygen species (ROS), resulting in a hypoxic tumor environment to activate the prodrug TPZ to achieve efficient chemotherapy, thereby evoking a synergistic photodynamic and chemotherapy therapeutic effect. The cascade synergistic therapeutic effect of DHM-Ce6@TPZ was effectively evaluated both in vitro and in vivo to inhibit tumor growth in a breast cancer mice model.

Conclusion

The designed multifunctional micellar nano platform could be a convenient and powerful vehicle for the efficient co-delivery of photosensitizers and chemical drugs for enhanced synergistic photodynamic and chemotherapy therapeutic effect of cancer.

Functionalized Nanomaterials for Inhibiting ATP-Dependent Heat Shock Proteins in Cancer Photothermal/Photodynamic Therapy and Combination Therapy

Phototherapies induced by photoactive nanomaterials have inspired and accentuated the importance of nanomedicine in cancer therapy in recent years. During these light-activated cancer therapies, a nanoagent can produce heat and cytotoxic reactive oxygen species by absorption of light energy for photothermal therapy (PTT) and photodynamic therapy (PDT). However, PTT is limited by the self-protective nature of cells, with upregulated production of heat shock proteins (HSP) under mild hyperthermia, which also influences PDT. To reduce HSP production in cancer cells and to enhance PTT/PDT, small HSP inhibitors that can competitively bind at the ATP-binding site of an HSP could be employed. Alternatively, reducing intracellular glucose concentration can also decrease ATP production from the metabolic pathways and downregulate HSP production from glucose deprivation. Other than reversing the thermal resistance of cancer cells for mild-temperature PTT, an HSP inhibitor can also be integrated into functionalized nanomaterials to alleviate tumor hypoxia and enhance the efficacy of PDT. Furthermore, the co-delivery of a small-molecule drug for direct HSP inhibition and a chemotherapeutic drug can integrate enhanced PTT/PDT with chemotherapy (CT). On the other hand, delivering a glucose-deprivation agent like glucose oxidase (GOx) can indirectly inhibit HSP and boost the efficacy of PTT/PDT while combining these therapies with cancer starvation therapy (ST). In this review, we intend to discuss different nanomaterial-based approaches that can inhibit HSP production via ATP regulation and their uses in PTT/PDT and cancer combination therapy such as CT and ST.

Poly(Glutamic Acid)-Engineered Nanoplatforms for Enhanced Cancer Phototherapy

Phototherapies, including photothermal therapy and photodynamic therapy, have gained booming development over the past several decades for their attractive non-invasiveness nature, negligible adverse effects, minimal systemic toxicity, and high spatial selectivity. Phototherapy usually requires three components: light irradiation, photosensitizers, and molecular oxygen. Photosensitizers can convert light energy into heat or reactive oxygen species, which can be used in the tumor-killing process. The direct application of photosensitizers in tumor therapy is restricted by their poor water solubility, fast clearance, severe toxicity, and low cellular uptake. The encapsulation of photosensitizers into nanostructures is an attractive strategy to overcome these critical limitations. Poly(glutamic acid) (PGA) is a kind of poly(amino acid)s containing the repeating units of glutamic acid. PGA has superiority for cancer treatment because of its good biocompatibility, low immunogenicity, and modulated pH responsiveness. The hydrophilicity nature of PGA allows the physical entrapment of photosensitizers and anticancer drugs via the construction of amphiphilic polymers. Moreover, the pendent carboxyl groups of PGA enable chemical conjugation with therapeutic agents. In this mini-review, we highlight the stateof- the-art design and fabrication of PGA-based nanoplatforms for phototherapy. We also discuss the potential challenges and future perspectives of phototherapy, and clinical translation of PGA-based nanomedicines.

Tumor microenvironment-activated theranostic nanoreactor for NIR-II Photoacoustic imaging-guided tumor-specific photothermal therapy

Theranostic agents that can be sensitively and specifically activated by the tumor microenvironment (TME) have recently attracted considerable attention. In this study, TME-activatable 3,3',5,5'-tetramethylbenzidine (TMB)-copper peroxide (CuO2)@poly(lactic-co-glycolic acid) (PLGA)@red blood cell membrane (RBCM) (TCPR) nanoparticles (NPs) for second near-infrared photoacoustic imaging-guided tumor-specific photothermal therapy were developed by co-loading CuO2 NPs and TMB into PLGA camouflaged by RBCMs. As an efficient H2O2 supplier, once exposed to a proton-rich TME, CuO2 NPs can generate H2O2 and Cu2+, which are further reduced to Cu+ by endogenous glutathione. Subsequently, the Cu+-mediated Fenton-like reaction produces cytotoxic ·OH to kill the cancer cells and induce TMB-mediated photoacoustic and photothermal effects. Combined with the RBCM modification-prolonged blood circulation, TCPR NPs display excellent specificity and efficiency in suppressing tumor growth, paving the way for more accurate, safe, and efficient cancer theranostics.