Hollow MnO2 as a tumor-microenvironment-responsive biodegradable nano-platform for combination therapy favoring antitumor immune responses

Self-oxygenating nanoplatform integrating CRISPR/Cas9 gene editing and immune activation for highly efficient photodynamic therapy

Photodynamic therapy (PDT) has arisen as a promising method due to its spatiotemporal precision and minimal invasiveness. It encounters significant obstacles in solid tumors due to hypoxia-induced therapeutic resistance and the self-protective mechanisms of cancer cells facilitated by MutT homolog 1 (MTH1), an enzyme involved in oxidative damage repair. Herein, we fabricate a tumor-microenvironment responsive CRISPR nanoplatform based on hollow mesoporous manganese dioxide (H-MnO2) for PDT. This platform utilizes H-MnO2 to produce oxygen (O2) through the decomposition of hydrogen peroxide (H2O2) in TME, thereby mitigating hypoxia and enhancing reactive oxygen species (ROS) generation. The high concentration of glutathione (GSH) and hyaluronidase (HAase) in TME induces the release of CRISPR/Cas9 ribonucleoproteins (RNP) to target the MTH1 gene, thereby impairs oxidative damage repair pathways and amplifys ROS-mediated cytotoxicity. The released Mn2+ ions function as immunomodulatory agents, activate innate immune responses via stimulating STING signal pathway. In vitro, IHMRH NPs markedly increased intracellular O2 levels, ROS production, lipid peroxidation and DNA damage, leading to tumor cell death, immune activation, and effective gene editing. In vivo, the nanoplatform suppressed tumor growth, diminished MTH1 gene expression, stimulated dendritic cell (DC) maturation through immunogenic cell death (ICD). This multimodal nanosystem may amplifies oxidative stress, collaborates with innate and adaptive immune activation to surpass the constraints of traditional PDT. The research presents a novel framework for cancer combination therapy by systematically integrating nanotechnology with precision gene editing.

Precision targeted melanoma therapy via cuproptosis/chemodynamic and chemotherapy: An engineering MCHS-CuMOF nanodelivery system

Melanoma, a highly aggressive skin cancer, continues to challenge current therapeutic modalities due to its resistance and high mortality rates. Recent advancements highlight cuproptosis, a copper-driven form of programmed cell death, as a promising target for melanoma treatment. This study integrated machine learning and large-scale genomic data to identify FDX1 as a pivotal gene in cuproptosis-related pathways for melanoma. We developed a novel nanomedicine, ACM@MCHS-CuMOF@Dox, combining Mesoporous Carbon Hollow Spheres (MCHS) loaded with Copper-based Metal-Organic Frameworks (CuMOFs) and Doxorubicin (Dox), to exploit this discovery. The nanomedicine leverages a biomimetic approach by incorporating A375 cell membranes, enhancing tumor-targeted delivery. Physicochemical characterization confirms optimal drug loading and pH/GSH-responsive release profiles. In vitro studies demonstrate that ACM@MCHS-CuMOF@Dox inhibits melanoma cell proliferation, migration, and invasion, outperforming other formulations. Mechanistic investigations revealed that ACM@MCHS-CuMOF@Dox induced robust apoptosis and cuproptosis through FDX1 downregulation, thereby enhancing oxidative stress and therapeutic efficacy. These findings underscore the potential of combining machine learning-driven target identification with advanced nanomedicine for precision melanoma therapy. This approach offers a promising strategy for overcoming current treatment limitations and advancing personalized cancer care.

Bioresponsive nanoreactor initiates cascade reactions for tumor vascular normalization and lactate depletion to augment immunotherapy

Immune checkpoint blockade (ICB) therapy has revolutionized cancer treatment. However, abnormal tumor vasculature and excess lactate contribute to tumor immunosuppression and confer resistance to ICB therapy, seriously limiting its clinical application. Here, we have developed a bioresponsive nanoreactor, ALMn, which consists of hollow manganese dioxide nanoparticles with encapsulation of lactate oxidase and L-Arginine, to overcome immunosuppression and sensitize ICB therapy. In the tumor microenvironment, lactate oxidase catalyzes lactate to produce hydrogen peroxide, which subsequently oxidizes L-Arginine to generate nitric oxide for vascular normalization. Through cascade reactions, ALMn effectively depletes excess lactate and normalize tumor vasculature, reshaping the immunosuppressive phenotype to an immune-activated one. Transcriptomics and immunological analyses prove that ALMn facilitates the infiltration and activation of effector cells, further potentiating antitumor immunity. Consequently, ALMn sensitizes anti-PD-L1 therapy, significantly suppressing tumor growth with an 83.7 % suppression, and prolonging the survival of mice, with the median survival time increasing from 29.5 days to 54.5 days. Our study demonstrates that ALMn effectively alleviates tumor immunosuppression and synergizes with anti-PD-L1, which shows promise in boosting ICB therapy.

A Single-Cell Atlas-Inspired Hitchhiking Therapeutic Strategy for Acute Pancreatitis by Restricting ROS in Neutrophils

Neutrophils can undergo transcriptional and epigenetic reprogramming in disease, thus causing inflammation or modulating tissue repair and fibrosis. A thorough understanding of the neutrophil subpopulation composition and their polarization processes in acute pancreatitis (AP) is essential to open up design of treatments tailored to individual patients. Herein, this study distinct subgroups and two differentiation pathways associated with N1 and N2 polarization during AP by single-cell sequencing. Inspired by this, a hollow manganese dioxide (HMnO2)-based nanoreactor (Pyp@APHM) conjugated with neutrophil-binding Ly-6G antibody and loaded with porphyrin is developed for targeted and in situ modulation of neutrophil polarization. Pyp@APHM can enrich the AP site by hitchhiking on neutrophils and then degrade in response to a weakly acidic environment to simultaneously release manganese ions and porphyrin ligands, enabling in situ synthesis of manganese porphyrin antioxidants. Leveraging this strategy, Pyp@APHM can effectively eliminate reactive oxygen species (ROS) and broadly inhibit both N1 and N2 polarization, as well as enhance tissue oxygenation by generating O2, thereby further mitigating pancreatic inflammation. This study provides a comprehensive single-cell atlas of neutrophils in AP and proposes an innovative hitchhiking therapeutic strategy for AP by restricting ROS in neutrophils.

Embracing cancer immunotherapy with manganese particles

A substance integral to the sustenance and functionality of virtually all forms of life is manganese (Mn), classified as an essential trace metal. Its significance lies in its pivotal role in facilitating metabolic processes crucial for survival. Additionally, Mn exerts influence over various biological functions including bone formation and maintenance, as well as regulation within systems governing immunity, nervous signaling, and digestion. Manganese nanoparticles (Mn-NP) stand out as a beacon of promise within the realm of immunotherapy, their focus honed on intricate mechanisms such as triggering immune pathways, igniting inflammasomes, inducing immunogenic cell death (ICD), and sculpting the nuances of the tumor microenvironment. These minuscule marvels have dazzled researchers with their potential in reshaping the landscape of cancer immunotherapy - serving as potent vaccine enhancers, efficient drug couriers, and formidable allies when paired with immune checkpoint inhibitors (ICIs) or cutting-edge photodynamic/photothermal therapies. Herein, we aim to provide a comprehensive review of recent advances in the application of Mn and Mn-NP in the immunotherapy of cancer. We hope that this review will display an insightful view of Mn-NPs and provide guidance for design and application of them in immune-based cancer therapies.

pH/GSH Dual-Responsive Janus-Type Au@H-MP@DOX MR Molecular Imaging Nanomotor for Combined Photothermal/Chemotherapeutic Treatment of Pancreatic Cancer

Chemotherapy is a widely used cancer treatment modality, while the complex tumor microenvironment (TME) significantly impedes drug delivery and deep tissue penetration. An MR molecular imaging drug-loaded nanomotor has been developed to achieve deep tumor tissue penetration and imaging-guided drug delivery, enabling combined photothermal and chemotherapeutic treatment of pancreatic cancer. A Janus-type nanomotor (Au@H-MP NMs) was fabricated via magnetron sputtering for application in photothermal therapy. Doxorubicin (DOX) was loaded onto one hemisphere of the nanomotor, achieving combined photothermal and chemotherapeutic treatment. Additionally, the nanomotor exhibits dual responsiveness to pH and glutathione (GSH), facilitating the controlled release of DOX within deep tumor tissues. Studies confirmed the nanomotors excellent biosafety, strong photothermal conversion capability, and effective induction of apoptosis. Tumor tissue penetration was validated through in vitro migration and infiltration assays, while in vivo experiments demonstrated significant tumor suppression and enhanced drug accumulation. Moreover, MR imaging technology enables real-time monitoring of nanomotor dynamics. These findings suggest that the synthesized Janus-type MR molecular imaging nanomotor offers a promising strategy for multimodal treatment of pancreatic cancer with significant clinical potential.

Light-Responsive Oxygen Generation from Chlorella Hydrogels for Facial Nerve Injury Recovery: Crosstalk between M1/M2 Macrophages and Schwann Cells

Facial nerve injury (FNI), hindered by hypoxic microenvironments limiting Schwann cell (SCs) repair potential, remains a therapeutic challenge. We developed light-responsive Chlorella hydrogels (C-Gel) to modulate oxygen release and inflammation. In vitro, light-activated C-Gel enhanced RSC96 SC proliferation, migration, and secretion while reducing reactive oxygen species (ROS), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). It also shifted macrophage polarization from pro-inflammatory M1 (inducible nitric oxide synthase (iNOS)+/TNF-α+) to anti-inflammatory M2 (arginase-1 (Arg-1)+/IL-10+), with M2-conditioned mediumboosting SCs production of neurotrophic factors (nerve growth factor, NGF; glial cell line-derived neurotrophic factor, GDNF), adhesion molecules (neural cell adhesion molecule-1, NCAM-1), regeneration-associated proteins (c-JUN), and myelin components (myelin basic protein, MBP; myelin-associated glycoprotein, MAG). In vivo, C-Gel-light therapy improved behavioral recovery in FNI rats, suppressed inflammation (ROS/HIF-1α/TNF-α), and enhanced SC-mediated remyelination (S100 calcium-binding protein, S100; neurofilament 200, NF200). RNA sequencing identified upregulated phosphoinositide 3-kinase-protein kinase (PI3K-Akt) and calcium ion (Ca²+) signaling pathways. This oxygen-regulating, immunomodulatory biomaterial offers a dual-action strategy to advance FNI rehabilitation by synergistically optimizing the regenerative microenvironment.

Manganese-Based Nanotherapeutics for Targeted Treatment of Breast Cancer

Breast cancer (BC) is one of the most common cancers among women and is associated with high mortality. Traditional modalities, including surgery, radiotherapy, and chemotherapy, have achieved certain advancements but continue to combat challenges including harm to healthy tissues, resistance to treatment, and adverse drug reactions. The rapid advancements in nanotechnology recently facilitated the exploration of innovative strategies for breast cancer therapy. Manganese-based nanotherapeutics have attracted great attention because of their unique characteristics such as tunable structures/morphologies, versatility, magnetic/optical properties, strong catalytic activities, excellent biodegradability, and biocompatibility. In this review, we highlighted different types of Mn-based nanotherapeutics to modulate TME, including metal-immunotherapy, alleviating tumor hypoxia, and increasing reactive oxygen species production, and we emphasized its role in magnetic resonance imaging (MRI)-guided therapy, photoacoustic imaging, and theranostic-based therapy along with a therapeutic carrier, all of which were discussed in the context of breast cancer. Hopefully, the present review will provide insights into the current landscape and future directions of multifunctional applications of Mn-based nanotherapeutics in the field of breast cancer treatment.

Immunomodulatory effects of metal nanoparticles: current trends and future prospects

The advent of nanotechnology has steered into a new era of medical advancements, with metal nanoparticles (MNPs) emerging as potent agents for precise regulation of the immune system. This review provides a comprehensive overview of the immunomodulatory roles of MNPs, including gold, silver, and metal oxide nanoparticles, in regulating innate and adaptive immunity. Additionally, we discuss the immunological effects of metal ions and metal complexes, offering a comparative analysis with nanoparticulate systems. We analyse cutting-edge strategies utilising MNPs to optimise vaccine efficacy, achieve targeted delivery to immune cells, and orchestrate inflammatory responses. Additionally, we discuss the therapeutic potential of MNPs in combating autoimmune diseases, cancers, and infectious agents, which is evaluated within the framework of precision medicine. Furthermore, we critically assess challenges such as biocompatibility, potential toxicity, and regulatory hurdles. Finally, we propose future directions for integrating MNPs with advanced delivery systems and other nanomaterials to propel the frontiers of immunotherapy. This review aims to provide a foundational understanding of MNP-mediated immunomodulation, inspiring further research and development in this burgeoning field.

Photothermal-enhanced ROS storm by hyaluronic acid-conjugated nanocatalysts to amplify tumor-specific photo-chemodynamic therapy and immune response

Integrating photodynamic therapy (PDT) and chemodynamic therapy (CDT) shows promising potential in tumor treatment. Nevertheless, the lack of specific tumor targeting, serious photobleaching, and poor photothermal effect of photosensitizers, the intracellular low Fenton reaction efficiency, and glutathione (GSH)-elicited reactive oxygen species (ROS) depletion profoundly restrict ROS-mediated cancer therapy. To enhance ROS generation with the assistance of photothermal therapy (PTT), the hyaluronic acid (HA)-decorated Fe-MIL-88B (MIL) nanocatalysts were fabricated for tumor-targeted delivery of photosensitizer IR820. The IR820@HA-coated MIL (IHM) nanocatalysts remarkably enhanced the photothermal conversion efficacy and singlet oxygen (1O2) production of IR820 and lowered IR820 photobleaching. The IHM nanocatalysts promoted the conversion of H2O2 into toxic ·OH upon thermo/acidity-enhanced Fe3+-mediated Fenton reaction and consumed GSH via Fe3+-elicited GSH oxidation. After being internalized by 4 T1 cancer cells via CD44-mediated endocytosis, the IHM nanocatalysts under irradiation of near-infrared (NIR) laser prominently produced hyperthermia and strong ROS storm, thereby causing apoptosis and ferroptosis via mitochondria damage and lipid peroxidation, and inducing immunogenic cell death (ICD). Through HA-mediated tumor targeting, the IHM nanocatalysts effectively accumulated in 4 T1 tumor and inhibited tumor growth and lung metastasis by PTT-enhanced PDT/CDT combined with ferroptosis and ICD-amplified antitumor immune response, showing great promise in future tumor treatment.

Nanoarchitecting intelligently encapsulated designs for improved cancer therapy

Despite the success in exploring various aspects of origination and therapeutic strategies, cancer has remained one of the most dreadful metabolic disorders due to failure to eradicate tumors comprehensively and frequent recurrence because of acquired resistance to the drugs. Recently, several advancements have been evidenced in the fabrication of various smart nanocarriers encapsulated with multiple components. Several reasons for smart nanoencapsulation include the enhancement of the bioavailability of drugs, precise targetability to reduce adverse effects on normal cells, and the ability to enable controlled drug release rates at the tumor sites. In addition, these smart nanocarriers protect encapsulated therapeutic cargo from deactivation, responsively delivering it based on the physiological or pathological characteristics of tumors. In this review, we present various smart approaches for cancer therapy, including organic materials, inorganic components, and their composites, as well as biomembrane-based nanoencapsulation strategies. These nanoencapsulation strategies, along with practical applications and their potential in cancer treatment, are discussed in depth, highlighting advantages and disadvantages, as well as aiming to reveal the ultimate prospects of nanoencapsulation in enhancing drug delivery efficiency and targeted cancer therapy.

Engineered Macrophage Membrane-Camouflaged Nanodecoys Reshape the Infectious Microenvironment for Efficient Periodontitis Treatment

A vicious cycle between microbiota dysbiosis and hyperactivated inflammation, hardly disrupted by conventional therapies, remains a significant clinical challenge for periodontitis treatment. Herein, by cloaking a cascade catalysis system in an engineered macrophage membrane, a nanodecoy-based strategy, with targeted bacteria-killing and immunomodulatory abilities, is proposed for reshaping the hostile periodontitis microenvironment. Specifically, recombinant human antimicrobial peptide, LL-37, is anchored to a Toll-like receptor-enriched macrophage membrane via genetic engineering, which facilitates the specific bacteria elimination and efficient tissue retention of the nanodecoys. Moreover, the cascade catalysis system integrates L-amino acid oxidase (LAAO) with hollowed manganese dioxide (hMnO2) by reciprocal elevation of the catalytic efficiency of hMnO2 and LAAO, leading to accelerated O2 generation under a hypoxic microenvironment and disrupted metabolism of periodontopathogenic bacteria. Notably, the nanodecoys trigger the nuclear translocation of NF-E2-related factor-2 (NRF2) to reduce oxidative stress response and rewire the polarization of macrophages, thereby boosting the osteogenic differentiation of osteoblasts. Furthermore, the alveolar bone regeneration therapeutically benefits from the nanodecoys in vivo. Altogether, these results highlight the attractive functions of engineered macrophage membrane-cloaked nanodecoys for effective periodontitis treatment.

Inflammation Targeting and Responsive Multifunctional Drug-Delivery Nanoplatforms for Combined Therapy of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by persistent inflammation, joint swelling, pain, and progressive joint destruction. Methotrexate (MTX) is the standard first-line treatment for RA, but its clinical application is hindered by poor water solubility and non-specific delivery. In this work, a multifunctional drug-delivery nanoplatform that targets both macrophages and tumor necrosis factor α (TNFα) is developed to enhance the therapeutic efficacy of MTX in RA. The nanoplatform consists of folic acid (FA, for macrophage targeting) and a TNFα-specific Aptamer (TNFα-Apt), facilitating a dual-targeting strategy that significantly improves the accumulation of MTX at the sites of RA lesions (≈3.5-fold). Moreover, the manganese dioxide (MnO₂) and polydopamine (PDA) coatings on the nanoplatform effectively scavenge reactive oxygen species (ROS), generate oxygen, and promote the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2 macrophages. This shift in macrophage polarization restores the expression of key inflammatory cytokines, improving the local inflammatory microenvironment. Ultimately, the nanoplatform significantly ameliorates the inflammation and joint damage in a collagen-induced arthritis (CIA) model, suggesting that this multi-target combination therapy holds considerable potential for the treatment of RA in vivo.

In Situ and Real-Time Multi-Modality Imaging Guided Orderly Triple-Therapy of Tumors with a Multifunctional Nanodrug

Effective integration of different therapeutic methods is a promising way to improve the overall efficacy of tumor therapy, which needs to be guided by in situ and real-time monitoring of each therapeutic process. Here a multifunctional AuNR@SiO2@MnO2@DNA prodrugs (ASMD) nanodrug is designed for orderly photothermal therapy (PTT)/chemodynamic therapy (CDT)/gene therapy (GT) triple-therapy of tumors, which can be guided by the in situ and real-time photoacoustic (PA)/magnetic resonance (MR)/fluorescence (FL) multi-modality imaging. The gold nanorod in ASMD can generate a PA signal and perform PTT. The MnO2 in ASMD can respond to the glutathione inside tumor cells to release Mn2+, which can generate MR signal and perform CDT by catalyzing the degradation of intracellular H2O2 to generate ·OH. The DNA prodrugs can perform a cascade response in the presence of the released Mn2+ and the intracellular microRNA 21, which can turn on the quenched FL signal and release small-interfering RNA and antisense oligonucleotide to perform GT. Guiding by the in situ and real-time PA/MR/FL multi-modality imaging of each therapeutic process, an orderly PTT/CDT/GT triple-therapy of tumors is established, which provides a significant and promising strategy to develop more efficient and practical therapeutic programs for tumors.

Naphthazarin Mounted on the Manganese Carbonate Nanocube Induced Enrichment of Endogenous Copper and Fenton-like Reaction for Enhanced Chemodynamic Therapy

Chemodynamic therapy (CDT), which utilizes transition metal ions to catalyze Fenton-like reactions for the eradication of tumor cells, has attracted substantial attention in the field of nanocatalysis. However, the therapeutic efficacy of CDT as a monotherapy is often limited by an insufficient level of hydrogen peroxide (H2O2) and the overexpressed glutathione (GSH) within tumor cells. Because of the high copper content in tumor tissues, a copper ionophore was strategically employed to enhance the intracellular accumulation of copper, thereby potentiating the CDT effect. Additionally, bovine serum albumin (BSA) was used to modify the copper ionophore, naphthazarin (Nap), to promote its targeting efficacy for tumor cells and to ensure its biosafety. The BSA-coated Nap nanoparticles, which could recruit Cu2+ in situ, were further deposited onto the surface of a manganese carbonate nanocube (Nap-BM NPs). The synergistic action of copper and manganese ions accelerated the decomposition of H2O2 into hydroxyl radicals (•OH) and consumed intracellular GSH, leading to cellular mortality via mitochondrial pathways. With low cytotoxicity and good biocompatibility in normal cells, the developed Nap-BM NPs significantly enhanced therapeutic outcomes by leveraging multiple Fenton-like reaction mechanisms to augment CDT, offering promising potential for clinical applications and contributing valuable insights into the field.

Nanoarchitectured hyaluronic acid-decorated hierarchical drug-like assemblies as synergistic immune modulators against breast carcinoma

Considering the challenges of delivering drugs using nanoparticles, fabricating an intelligent drug-like nanocomposite platform with exceptional therapeutic effects has attracted enormous interest in achieving safe and highly effective tumor treatment. Although the activation of materials using external sources (light) is of great importance, it is obligatory to synergistically activate the internal stimuli, such as deadly free radicals and immune responses. This study aims to fabricate conformational biocompatible nanoassemblies based on in-situ grown platinum nanodots (Pt NDs) on the surface of manganese dioxide (MnO2) nanoflowers, followed by hyaluronic acid (HA) encapsulation (shortly HMP), enabling chemodynamic therapy (CDT), photothermal therapy (PTT), photothermal imaging, and immunotherapy synergistically. The HMP nanocomposites with enhanced photothermal conversion efficiency could deplete GSH in the tumor microenvironment, followed by the release of Mn2+ and Pt NDs. Mn2+ could further react with H2O2 to generate hydroxyl radicals (·OH) through a Fenton-like reaction, resulting in the CDT effect. The presence of Pt NDs showed an improvement in the photothermal conversion efficiency of HMP nanoassemblies (35.46 %) towards the PTT effect. In addition to synergistic (CDT and PTT) actions in 4 T1 cells in vitro, low doses of HMP nanocomposites could stimulate the high mobility group box 1 (HMGB-1) release and generate calreticulin (CRT) protein in tumor cells to provide necessary signals for immunotherapeutic destruction. Finally, HMP nanocomposites combined with light stimulation could effectively inhibit tumor growth in BALB/c tumor-bearing mice. In summary, the designed drug-free nanoassemblies resulted in enhanced tumor suppression through synergistic CDT, PTT, and potential immunotherapy therapeutic effects.

Manganese-based nanoparticles plus gambogic acid targeted hypoxic tumor microenvironment by enhancing ROS generation and provided antitumor treatment and improved immunotherapy

Colorectal cancer (CRC) remains a major global health challenge, particularly in advanced stages where drug resistance leads to high recurrence rates and poor survival outcomes. This study investigates a novel therapeutic approach combining gambogic acid (GA) with manganese dioxide (MnO2) nanoparticles (MBG NPs) to enhance anti-tumor efficacy in the acidic and hypoxic tumor microenvironment (TME). The development of MBG NPs involved conjugating MnO2 nanosheets with bovine serum albumin (BSA) for effective GA encapsulation, optimizing the delivery of both components. We explored the potential of Mn2+ ions released from MnO2 to synergize with GA to alleviate tumor hypoxia and modulate the TME, thereby improving immune response. In vitro assays demonstrated significant cytotoxicity of MBG NPs against mouse colon cancer cells (CT26 cells), with enhanced apoptosis and elevated reactive oxygen species (ROS) levels. In vivo studies using BALB/c mice showed that treatment with MBG NPs significantly reduced tumor volumes and improved survival rates compared to controls. Additionally, MBG NPs combined with programmed death-1 inhibitor (aPD-1) further augmented therapeutic effects. Histological analyses confirmed tumor necrosis and changes in TME composition, indicating the potential of this synergistic strategy to overcome drug resistance in microsatellite stable (MSS) CRC, inhibit tumor growth and benefit patient survival. These findings highlight the promising application of nanoparticle-based platforms in enhancing immunotherapy outcomes for advanced colorectal cancer.

Ultra-Small Iron-Based Nanoparticles with Mild Photothermal-Enhanced Cascade Enzyme-Mimic Reactions for Tumor Therapy

Chemodynamic therapy (CDT), which utilizes the catalytic reactions of nanoparticles to inhibit tumor growth, is a promising approach in cancer therapy. However, its efficacy is limited by insufficient hydrogen peroxide (H2O2) concentration in tumor microenvironments and unsatisfactory enzymatic catalytic activity. To overcome these limitations, ultra-small iron-based (USIB) nanoparticles with cascaded superoxide dismutase (SOD)-mimic and peroxidase (POD)-mimic activities have been engineered. USIB nanoparticles initiated by SOD-mimic activity to transform superoxide anions (O2·-) into H2O2, elevating H2O2 levels in the tumor microenvironment and subsequently utilizing POD-mimic activity to convert H2O2 into the more reactive ·OH, thereby achieving the destruction of tumor cells. In addition, USIB nanoparticles possess photothermal conversion capabilities, and their enzymatic activity can be significantly enhanced under mild laser irradiation. Therefore, by addressing the issues of insufficient substrate concentration and low enzymatic catalytic activity, the therapeutic efficiency of CDT has been improved. Our research integrates the cascade catalytic reactions of nanozymes with laser irradiation, effectively inhibiting tumor growth and exhibiting outstanding biosafety, demonstrating promising therapeutic potential.

Manganese-based nanoenzymes: from catalytic chemistry to design principle and antitumor/antibacterial therapy

Manganese (Mn)-based materials have been extensively investigated for a wide range of biomedical applications owing to their remarkable catalytic chemistry, magnetic resonance imaging (MRI) capacity, biodegradability, low toxicity, and good biosafety. In this review, we first elaborate on the catalytic principle of Mn-based nanoenzymes for antitumor and antibacterial therapy, followed by a comprehensive discussion of the interesting structural design engineering strategies used to achieve multi-dimensional Mn-based nanoarchitectures, such as zero-dimensional (0D) nanoparticles, 1D nanotubes, 2D nanosheets, 3D hollow porous Mn ball, and core-shell nanostructures. Moreover, the therapeutic applications of different Mn-based nanoenzymes, including manganese dioxide (MnO2)-based nanoenzymes that can trigger catalytic reactions, Mn2+-doped metal nanoenzymes and Mn2+-coordinated nanoenzymes that promote hydroxyl/reactive oxygen species (ROS) generation, and MnO2-based micro/nanorobots that can effectively penetrate tumor tissues, are critically reviewed. Finally, a brief overview of the potential challenges faced in the development of Mn-based nanoenzymes is presented, along with a comparative and balanced discussion of future prospects.

Spherical Nucleic Acids-Directed Cryosynthesis of Manganese Nanoagents for Tumor Imaging and Therapy

DNAzyme-based theranostic nanotechnologies that can respond to specific tumor pathophysiological parameters hold great promise for tumor diagnostics and effective treatments. However, their clinical translation is hindered by insufficient intracellular availability of essential metal cofactors required for DNAzyme activation. To overcome this limitation, we developed a temperature-controlled synthesis strategy for fabricating multifunctional DNA-templated manganese carbonate nanoparticles (DtMnP). The process involves three critical phases: (i) spherical nucleic acid hybrids, DNAzyme-functionalized AuNPs, serve as scaffolds for spatially controlled Mn2+ deposition through phosphate coordination, initiating heterogeneous nucleation of MnCO3; (ii) rapid liquid nitrogen freezing induces nanoparticle growth along DNA templates; and (iii) lyophilization-mediated structural stabilization enables convenient long-term storage. The DtMnP exhibits pH-responsive dissolution, releasing 90% of Mn2+ within 60 min under tumor microenvironment conditions (pH 5.5). The released Mn2+ ion enables dual functionality: (i) superior magnetic resonance imaging (MRI) contrast of MCF-7 xenograft models with enhanced biosafety, and (ii) synergistic therapeutic efficacy through DNAzyme-mediated EGR-1 gene silencing (60% mRNA downregulation) combined with Mn2+-catalyzed Fenton reactions generating cytotoxic hydroxyl radicals (45% apoptosis in MCF-7 cells). The cryo-encapsulated DtMnP exemplifies a flexible and efficient approach for integrating various functional components into a single nanoparticle for tumor theranostic applications.

ATP-Exhausted Strategy Induced Anti-Tumor Low-Temperature Photothermal Therapy Based on Rare Earth Nanocrystals Modified Hollow Porous MnOx Nanozyme with TME-Activated NIR-II Imaging

Insufficient adenosine triphosphate (ATP) can reduce the synthesis of heat-stress-induced heat shock proteins (HSPs) to promote the efficiency of mild photothermal therapy (mPTT), thus the rational design of ATP-exhausted strategy based on nanotechnology is an effective approach to resuscitate mPTT. Herein, Nd3+ doped nanocrystals (NaYF4:Nd@CaF2, Nd-NCs) modified hollow mesoporous manganese oxide (H-MnOx) nanocomposite (H-MnOx@Nd-NCs, MN) is synthesized, and loaded with glucose transporters (GLUTs) inhibitor KL-11743, noted as MN-KL nanozyme. In tumor microenvironment (TME), MN-KL can react with overexpressed glutathione (GSH) to release KL-11743, which can suppress the synthesis of intracellular ATP at the source by blocking glucose uptake to inhibit HSPs expression, meanwhile, MN-KL catalyzes the production of ·O2 -/1O2/·OH and lipid peroxidation (LPO) to cleave existing HSPs. Through a two-pronged strategy with ATP inhibition and oxide accumulation, reducing the level of HSPs can be guaranteed for achieving efficient mPTT in both subcutaneous and in situ tumor models in mice. During this process, Nd-NCs can absorb near-infrared light and convert it into heat, and the quenched fluorescence of Nd-NCs by H-MnOx can be recovered through GSH-triggered biodegradation in tumors, thus the modification of Nd-NCs not only provides photothermal effect but also enables MN to own TME-activated fluorescence imaging.

Unleashing the Potential of Metal Ions in cGAS-STING Activation: Advancing Nanomaterial-Based Tumor Immunotherapy

Immunotherapy is a critical modality in cancer treatment with diverse activation pathways. In recent years, the stimulator of interferon genes (STING) signaling pathway has exhibited significant potential in tumor immunotherapy. This pathway exerts notable antitumor effects by activating innate and adaptive immunity and regulating the tumor immune microenvironment. Various metal ions have been identified as effective activators of the STING pathway and, through the design and synthesis of nanodelivery platforms, have been applied in immunotherapy as well as in combination therapies, such as chemotherapy, chemodynamic therapy, photodynamic therapy, and cancer vaccines. Metal nanomaterials showcase unique advantages in immunotherapy; however, there are still aspects that require optimization. This review systematically examines existing metal-based nanomaterials, elaborates on the mechanisms by which different metal ions activate the STING pathway, and discusses their application models in tumor combination therapies. We also provide a comparative analysis of the advantages of metal nanomaterials over other treatment methods. Our exploration highlights the broad application prospects of metal nanomaterials in cancer treatment, offering new insights and directions for the advancement of tumor immunotherapy.

Tumor-microenvironment-mediated second near-infrared light activation multifunctional cascade nanoenzyme for self-replenishing O2/H2O2 multimodal tumor therapy

Developing a catalytic nanoenzyme activated by the tumor microenvironment (TME) shows excellent potential for in situ cancer treatment. However, the rational design of a cascade procedure to achieve high therapeutic efficiency remains challenging. In this study, the colorectal TME-responsive multifunctional cascade nanoenzyme Cu2-xO@MnO2@glucose oxidase (GOx)@hyaluronic acid (HA) was developed to target in situ cancer starvation/chemodynamic therapy (CDT)/photothermal therapy (PTT). First, the MnO2 nanolayer specifically decomposes within the acidic TME to generate Mn2+ and oxygen (O2), thereby alleviating the hypoxic TME. Subsequently, Cu2-xO can be vulcanized into Cu2-xS by overexpressing sulfuretted hydrogen (H2S) gas in the colorectal tumor for a second near-infrared (NIR-II) light-triggered deep tissue PTT. Cu2-xS nanoparticles can react with hydrogen peroxide (H2O2) to generate hydroxyl radical (OH) for the CDT. In addition, GOx catalyzes the conversion of glucose into H2O2 for starvation therapy and enhances the CDT efficiency by self-supplying H2O2. Interestingly, the generated reactive oxygen species (ROS) induce immunogenic cell death (ICD), which further activates adaptive cancer immunity for anti-tumor immunotherapy. Finally, therapeutic efficiency was greatly improved after coating with tumor-targeted HA. Collectively, these TME-responsive cascade nanoenzymes can realize PTT, CDT starvation therapy, and immunotherapy, paving the way for the design of TME-responsive cascade nanoenzymes for synergistically enhanced tumor-specific therapy.

WO3-x@Ferrocene-Folic Acid Composites Induce Cancer Cell Death and Activate Immunity via PTT/CDT

At present, tumor immune escape is a major problem in the treatment of tumors. The complex network of tumor microenvironments significantly impairs the efficacy of immunotherapy. This paper reports the preparation and immunoantitumor activity of a novel multifunctional defect tungsten trioxide@ferrocene-folic acid composite (WO3-x@Fe-FA) with a high Fenton reaction rate. Ferrocene is modified on the surface of defective trioxide by the covalent coupling method for the first time, and the reaction rate of Fenton is increased by 10 times. WO3-x@Fe-FA induces immunogenic cell death (ICD) through the powerful synergistic anti-tumor effect of PTT/CDT and decomposes H2O2 to produce oxygen through the Fenton reaction, thus down-regulating the expression of immune checkpoint PD-L1 induced by tumor hypoxia. In vitro and in vivo experiments proved that WO3-x@Fe-FA reverses the immunosuppressive tumor microenvironment, transforms the immunosuppressive "cold tumor" into the immune "hot tumor", and activates the immune activity of the system. In vitro and in vivo experiments show that WO3-x@Fe-FA has excellent immunoantitumor activity, and it is expected to be a candidate drug for immunoantitumor therapy.

FePt/MnO2@PEG Nanoparticles as Multifunctional Radiosensitizers for Enhancing Ferroptosis and Alleviating Hypoxia in Osteosarcoma Therapy

Radiotherapy (RT) is a widely used cancer treatment, and the use of metal-based nanoradiotherapy sensitizers has demonstrated promise in enhancing its efficacy. However, achieving effective accumulation of these sensitizers within tumors and overcoming resistance induced by the hypoxic tumor microenvironment remain challenging issues. In this study, we developed FePt/MnO2@PEG nanoparticles with multiple radiosensitizing mechanisms, including high-atomic-number element-mediated radiation capture, catalase-mimicking oxygenation, and GSH depletion-induced ferroptosis. Both in vitro and in vivo experiments were conducted to validate the radiosensitizing mechanisms and therapeutic efficacy of FePt/MnO2@PEG. In conclusion, this study presents a novel and clinically relevant strategy and establishes a safe and effective combination radiotherapy approach for cancer treatment. These findings hold significant potential for improving radiotherapy outcomes and advancing the field of nanomedicine in cancer therapy.

Lab-in-Cell: A Covalent Photosensitizer Reverses Hypoxia and Evokes Ferroptosis and Pyroptosis for Enhanced Anti-Tumor Immunity

Photodynamic immunotherapy presents a non-invasive strategy characterized by spatiotemporal control and minimal side effects to induce immunogenic cell death (ICD). This approach significantly enhances the release of tumor-associated antigens and damage-associated molecular patterns, thereby improving cancer immunotherapy outcomes. However, hypoxia and antioxidant defenses at tumor sites considerably diminish the efficacy of photodynamic immunotherapy. In this work, a covalent warhead, alkyneamide, is introduced into an AIE photosensitizer to develop a novel covalent photosensitizer, MBTP-PA, which targets redox systems and facilitates ferroptosis- and pyroptosis-mediated photodynamic immunotherapy by thiol-yne click reactions. The covalent photosensitizer interacts with intracellular thiol compounds such as cysteine and glutathione, disrupting the intracellular antioxidant system and alleviating hypoxia. This results in enhanced photodynamic therapy (PDT) efficacy compared to the non-covalent photosensitizer MBTP-A. Furthermore, in conjunction with PDT, this reaction therapy can activate ICD through ferroptosis and pyroptosis, thereby enhancing anti-tumor immunity. Notably, in vivo injection of MBTP-PA nanoparticles at the tumor site led to the elimination of primary tumors, inhibiting distal tumors and exhibiting minimal side effects. Therefore, this work not only integrates the thiol-yne click reactions into cellular systems, significantly enhancing the efficacy of photodynamic immunotherapy but also paves the way for developing novel photosensitizers.

A Dual-Pipeline Lactate Removal Strategy to Reverse Vascular Hyperpermeability for the Management of Lipopolysaccharide-Induced Sepsis

Sepsis is an underappreciated yet severe threat to human life, marked by organ dysfunction and high mortality resulting from disordered inflammatory responses to blood infection. Unfortunately, no specific drugs are available for effective sepsis treatment. As a pivotal biomarker for sepsis, lactate levels are closely related to vascular permeability and sepsis-associated mortality. Herein, a dual-pipeline lactate removal strategy is reported from circulating blood to ameliorate vascular permeability and lipopolysaccharide (LPS)-induced sepsis. This is achieved by formulating lactate oxidase (LOX)-encapsulated hollow manganese dioxide (HMnO2) nanohybrids (LOX@HMnO2-P[5]A) bearing pillar[5]arene (P[5]A) macrocycle with excellent host-guest properties. The highly biocompatible nanohybrids enable direct lactate consumption through LOX catalytic degradation and block lactate production by P[5]A-mediated LPS trapping, allowing for dual-pipeline lactate removal to maximize the reversal of lactate-mediated vascular hyperpermeability. Besides, HMnO2 cores decompose hydrogen peroxide produced from lactate oxidation into oxygen, further contributing to lactate consumption and mitigating the hypoxic inflammatory environment. In vivo investigations demonstrate that intravenous administration of LOX@HMnO2-P[5]A nanohybrids with extended blood circulation can effectively ameliorate endothelial barrier dysfunction, inflammatory responses, and multiple organ injury, ultimately improving survival outcomes in LPS-induced sepsis. Taken together, this dual-pipeline lactate removal strategy offers a promising approach for efficient sepsis treatment.

A UOx@HMnO2 biozyme-nanozyme driven electrochemical platform for specific uric acid bioassays

Uric acid (UA) is a key end product of purine metabolism in the human body, and its abnormal levels are associated with many diseases, so accurate monitoring is essential. Existing detection methods have many limitations. For example, chromatography is cumbersome, time-consuming, and not cost-effective, while serum uric acid analysis requires specialized equipment and venous blood collection. In the field of uric acid sensors, electrochemical detection is commonly used but prone to interference, and nanomaterials offer improvements but are complicated to modify. To better block interference via an easily-made nanocomposite-based system, in this study, MnO2 with peroxidase-mimicking activity was used as a protective shell to encapsulate natural uric acid oxidase (UOx), realizing a good combination of nanozymes and biocatalysts. UOx can selectively catalyze UA and generate H2O2, and the MnO2 nanozymes can make up for the insufficiency of UOx, and the two main components synergistically enhance the activity of UOx@HMnO2, resulting in ultra-high performance. This provides a simple and general method for the preparation of efficient hybridized biocatalysts in the fields of biosensors and biocatalysis. The detection limit of the fabricated uric acid sensor is as low as 0.74 μM, and the concentration of the actual sample is consistent with that of mass spectrometry, which provides a means of non-invasive detection of uric acid with high sensitivity, high specificity and good accuracy.

Tumor microenvironment: recent advances in understanding and its role in modulating cancer therapies

Tumor microenvironment (TME) denotes the non-cancerous cells and components presented in the tumor, including molecules produced and released by them. Interactions between cancer cells, immune cells, stromal cells, and the extracellular matrix within the TME create a dynamic ecosystem that can either promote or hinder tumor growth and spread. The TME plays a pivotal role in either promoting or inhibiting tumor growth and dissemination, making it a critical factor to consider in the development of effective cancer therapies. Understanding the intricate interplay within the TME is crucial for devising effective cancer therapies. Combination therapies involving inhibitors of immune checkpoint blockade (ICB), and/or chemotherapy now offer new approaches for cancer therapy. However, it remains uncertain how to best utilize these strategies in the context of the complex tumor microenvironment. Oncogene-driven changes in tumor cell metabolism can impact the TME to limit immune responses and present barriers to cancer therapy. Cellular and acellular components in tumor microenvironment can reprogram tumor initiation, growth, invasion, metastasis, and response to therapies. Components in the TME can reprogram tumor behavior and influence responses to treatments, facilitating immune evasion, nutrient deprivation, and therapeutic resistance. Moreover, the TME can influence angiogenesis, promoting the formation of blood vessels that sustain tumor growth. Notably, the TME facilitates immune evasion, establishes a nutrient-deprived milieu, and induces therapeutic resistance, hindering treatment efficacy. A paradigm shift from a cancer-centric model to a TME-centric one has revolutionized cancer research and treatment. However, effectively targeting specific cells or pathways within the TME remains a challenge, as the complexity of the TME poses hurdles in designing precise and effective therapies. This review highlights challenges in targeting the tumor microenvironment to achieve therapeutic efficacy; explore new approaches and technologies to better decipher the tumor microenvironment; and discuss strategies to intervene in the tumor microenvironment and maximize therapeutic benefits.

Engineered macrophage membrane-coated nanoparticles attenuate calcium oxalate nephrocalcinosis-induced kidney injury by reducing oxidative stress and pyroptosis

Kidney stones are characterized by a high incidence and recurrence rate, leading to kidney injury, which in turn accelerates stone formation and deposition. Increasing evidence have demonstrated that oxidative stress and cell pyroptosis play important role in the calcium oxalate (CaOx) stones induced kidney injury. Currently, treatments related to oxidative stress and inflammation associated with kidney stones are still relatively limited. Here, we designed engineered macrophage cell membrane-coated hollow mesoporous manganese dioxide nanoparticles loaded with NLRP3 inhibitors Mcc950 (KM@M@M). KM@M@M NPs were modified with Kim-1 targeting peptides on M2-polarized macrophage membranes to achieve better targeted delivery to injured kidney tubules. Compared with traditional drugs, KM@M@M NPs reduce systemic toxicity through targeted drug delivery to the kidneys. In vivo and in vitro results demonstrate that KM@M@M NPs reduces the activation of the NLRP3 inflammasome in renal tubular epithelial cells by scavenging ROS, thereby downregulating gasdermin D cleavage and the production of inflammatory cytokines, ultimately inhibiting cell pyroptosis. In addition, bioinformatic analysis revealed that KM@M@M NPs protect against CaOx induced kidney injury via suppressing the NLRP3/GSDMD pathway. This article extending the application of engineered cell membrane-based biomimetic nanotechnology, and providing a promising strategy for dual protection in CaOx stones induced kidney injury. STATEMENT OF SIGNIFICANCE: Currently, apart from invasive surgery, there are few pharmacological therapies for CaOx-induced renal injury. This study presents a new strategy using engineered macrophage cell membrane-coated hollow mesoporous manganese dioxide nanoparticles (KM@M@M) to target and treat calcium oxalate (CaOx)-induced kidney injury. The nanoparticles effectively scavenge reactive oxygen species (ROS) and inhibit NLRP3 inflammasome activation, preventing pyroptosis and kidney damage. By delivering NLRP3 inhibitors directly to injured renal tubules, KM@M@M NPs reduce inflammation and stone deposition. This work demonstrates the potential of biomimetic nanotechnology for targeted treatment, offering a promising approach to prevent CaOx-induced renal injury and enhance therapeutic outcomes in kidney stone disease.

Harnessing the Power of Traditional Chinese Medicine in Cancer Treatment: The Role of Nanocarriers

For centuries, traditional Chinese medicine (TCM) has had certain advantages in the treatment of tumors. However, due to their poor water solubility, low bioavailability and potential toxicity, their effective delivery to target sites can be a major challenge. Nanocarriers based on the active ingredients of TCM, such as liposomes, polymer nanoparticles, inorganic nanoparticles, and organic/inorganic nanohybrids, are a promising strategy to improve the delivery of TCM, resulting in higher therapeutic outcomes and fewer side effects. Therefore, this article intends to review the application of Chinese medicine nano preparation in tumor. Firstly, we introduce the classification and synthesis of nanometer preparations of Chinese medicine. The second part mainly introduces the different responses of TCM nano-preparations in the course of treatment to introduce how TCM nano-preparations play a role in anti-tumor therapy. The third part focuses on Different response modes of Chinese medicine nano preparations in tumor therapy. The fourth part elucidates the application of Chinese medicine nano preparations in the treatment of cancer. Finally, the research direction to be explored in related fields is put forward.

Dual-Mode Tumor Diagnosis and Guided Precise Photodynamic Therapy Based on MicroRNA Fluorescence Signal Amplification and Magnetic Resonance Imaging

Accurate and early tumor diagnosis is critical for effective cancer treatment, yet current diagnostic modalities often face limitations. Fluorescence imaging (FLI) and magnetic resonance imaging (MRI) both offer substantial potential for cancer diagnosis. However, FLI suffers from poor tissue penetration, while MRI lacks molecular specificity. To address these limitations, we proposed a dual-modal diagnostic strategy by combining FLI and MRI for precise photodynamic therapy (PDT) of tumors. A degradable tumor microenvironment (TME)-responsive nanoplatform, i.e., UCNPs-MB@MnO2-H1/H2 (UBMD), was developed. Intracellular overexpression of miRNA-21 triggers an in situ hybridization chain reaction between H1-TAMRA and H2-FAM, which significantly amplifies fluorescence resonance energy transfer and enables FLI of miRNA-21 in living cancer cells. On the other hand, UBMD activates MRI in the TME to remarkably amplify tumor MRI signals and to effectively compensate for the shortcoming of weak penetration of FLI in deep tissues. UBMD exhibits an NIR-activated PDT capability to enable tumor-specific in situ diagnostics and imaging. In vivo miRNA-21 FLI and MR imaging in living mice actively guide precise and efficient PDT of tumors.

All-in-One: A Multifunctional Composite Biomimetic Cryogel for Coagulation Disorder Hemostasis and Infected Diabetic Wound Healing

Traditional hemostatic materials are difficult to meet the needs of non-compressible bleeding and for coagulopathic patients. In addition, open wounds are susceptible to infection, and then develop into chronic wounds. However, the development of integrated dressings that do not depend on coagulation pathway and improve the microenvironment of chronic wounds remains a challenge. Inspired by the porous structure and composition of the natural extracellular matrix, adipic dihydrazide modified gelatin (GA), dodecylamine-grafted hyaluronic acid (HD), and MnO2 nanozyme (manganese dioxide)@DFO (deferoxamine)@PDA (polydopamine) (MDP) nanoparticles were combined to prepare GA/HD/MDP cryogels through amidation reaction and hydrogen bonding. These cryogels exhibited good fatigue resistance, photothermal antibacterial (about 98% killing ratios of both Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) after 3 min near-infrared irradiation), reactive oxygen species scavenging, oxygen release, and angiogenesis properties. Furthermore, in the liver defect model of rats with coagulopathy, the cryogel displayed less bleeding and shorter hemostasis time than commercial gelatin sponge. In MRSA-infected diabetic wounds, the cryogel could decrease wound inflammation and oxidative stress, alleviate the hypoxic environment, promote collagen deposition, and induce vascular regeneration, showing a better repair effect compared with the Tegaderm™ film. These results indicated that GA/HD/MDP cryogels have great potential in non-compressible hemorrhage for coagulopathic patients and in healing infected wounds for diabetic patients.

MnO2@CeOx-GAMP radiosensitizer with oxygen vacancies depended mimicking enzyme-like activities for radiosensitization-mediated STING pathway activation

Activation of the stimulator of interferon genes (STING) pathway by radiotherapy (RT) has a significant effect on eliciting antitumor immune responses. The generation of hydroxyl radical (·OH) storm and the sensitization of STING-relative catalytic reactions could improve radiosensitization-mediated STING activation. Herein, multi-functional radiosensitizer with oxygen vacancies depended mimicking enzyme-like activities was fabricated to produce more dsDNA which benefits intracellular 2', 3'-cyclic GMP-AMP (cGAMP) generation, together with introducing exogenous cGAMP to activate immune response. MnO2@CeOx nanozymes present enhanced superoxide dismutase (SOD)-like and peroxidase (POD)-like activities due to induced oxygen vacancies accelerate the redox cycles from Ce4+ to Ce3+ via intermetallic charge transfer. CeOx shells not only serve as radiosensitizer, but also provide the conjugation site for AMP/GMP to form MnO2@CeOx-GAMP (MCG). Upon X-ray irradiation, MCG with SOD-like activity facilitates the conversion of superoxide anions generated by Ce-sensitization into H2O2 within tumor microenvironment (TME). The downstream POD-like activity catalyzes the elevated H2O2 into a profusion of ·OH for producing more damage DNA fragments. TME-responsive decomposed MCG could supply exogenous cGAMP, meanwhile the releasing Mn2+ improve the sensitivity of cyclic GMP-AMP synthase to dsDNA for producing more cGAMP, resulting in the promotion of STING pathway activation.

The Extra-Tumoral Vaccine Effects of Apoptotic Bodies in the Advancement of Cancer Treatment

The induction of apoptosis in tumor cells is a common target for the development of anti-tumor therapies; however, these therapies still leave patients at increased risk of disease recurrence. For example, apoptotic tumor cells can promote tumor growth and immune evasion via the secretion of metabolites, apoptotic extracellular vesicles, and induction of pro-tumorigenic macrophages. This paradox of apoptosis induction and the pro-tumorigenic effects of tumor cell apoptosis has begged the question of whether apoptosis is a suitable cancer therapy, and led to further explorations into other immunogenic cell death-based approaches. However, these strategies still face multiple challenges, the most critical of which is the tumor microenvironment. Contrary to the promotion of immune tolerance mediated by apoptotic tumor cells, apoptotic bodies with enriched tumor-related antigens have demonstrated great immunogenic potential, as evidenced by their ability to initiate systemic T-cell immune responses. These characteristics indicate that apoptotic body-based therapies could be ideal "in situ" extra-tumoral tumor vaccine candidates for the treatment of cancers, and further address the current issues with apoptosis-based or immunotherapy treatments. Although not yet tested clinically, apoptotic body-based vaccines have the potential to better treatment strategies and patient outcomes in the future.

Chemical Design of Magnetic Nanomaterials for Imaging and Ferroptosis-Based Cancer Therapy

Ferroptosis, an iron-dependent form of regulatory cell death, has garnered significant interest as a therapeutic target in cancer treatment due to its distinct characteristics, including lipid peroxide generation and redox imbalance. However, its clinical application in oncology is currently limited by issues such as suboptimal efficacy and potential off-target effects. The advent of nanotechnology has provided a new way for overcoming these challenges through the development of activatable magnetic nanoparticles (MNPs). These innovative MNPs are designed to improve the specificity and efficacy of ferroptosis induction. This Review delves into the chemical and biological principles guiding the design of MNPs for ferroptosis-based cancer therapies and imaging-guided therapies. It discusses the regulatory mechanisms and biological attributes of ferroptosis, the chemical composition of MNPs, their mechanism of action as ferroptosis inducers, and their integration with advanced imaging techniques for therapeutic monitoring. Additionally, we examine the convergence of ferroptosis with other therapeutic strategies, including chemodynamic therapy, photothermal therapy, photodynamic therapy, sonodynamic therapy, and immunotherapy, within the context of nanomedicine strategies utilizing MNPs. This Review highlights the potential of these multifunctional MNPs to surpass the limitations of conventional treatments, envisioning a future of drug-resistance-free, precision diagnostics and ferroptosis-based therapies for treating recalcitrant cancers.

Mini Review On: The Roles of DNA Nanomaterials in Phototherapy

DNA-based functional nanomaterials are distinguished by their structural designability and functional controllability, making them particularly attractive in the biomedical field. Using DNA nanomaterials for cancer treatment through synergistic approaches combining photodynamic therapy and photothermal therapy has garnered significant attention. This growing interest has driven the active development of various DNA nanomaterials tailored for integrated strategies targeting cancer, including phototherapy, chemotherapy, etc. This review provides an overview of DNA nanoplatforms employed in phototherapy and synergistic therapy for cancer treatment. It highlights recent advances in DNA nanoplatforms that leverage multifaceted synergy to enhance phototherapeutic efficacy. It also offers a new perspectives and clinical application potential of DNA nanomaterials in synergistic phototherapy for malignant tumors, focusing on developments in recent years and potential directions for future research and applications.

Thermosensitive liposome-encapsulated gold nanocages for photothermal-modulated drug release and synergistic photothermal therapy

Delivery nanosystems have been widely developed to improve the efficacy of chemotherapy. However, their performance regarding the non-specific leakage of drugs remained unsatisfactory. Herein, gold nanocages (AuNCs) were used as carriers and thermo-sensitive liposome (TSL) as a protective shell to design a camptothecin (CPT)-loaded delivery nanosystem (AuNCs/CPT@TSL) for photothermal-modulated drug release. This approach effectively avoided the non-specific leakage of CPT and enabled the combination of photothermal therapy (PTT) and chemotherapy. In the simulated tumor microenvironment (pH = 5.5), the TSL shell prevented CPT leakage at 37 °C, with a release rate of only 11.4%. However, the release rate of CPT greatly increased to 85.4% when the temperature was elevated to 45 °C. The photothermal conversion efficiency of AuNCs/CPT@TSL reached up to 46.1%. At an incubation temperature of 37 °C, the cell survival rate decreased to 43.6% in AuNCs/CPT but remained above 90% in AuNCs/CPT@TSL, demonstrating the protective effect of the TSL shell. Under the combination of PTT and chemotherapy, cell viability drastically decreased to 10.9%, and the tumors completely disappeared, confirming the safe and reliable antitumor effect of AuNCs/CPT@TSL.

Macrocycle-based self-assembled amphiphiles for co-delivery of therapeutic combinations to tumor

For tumor treatment, the efficiency of single chemotherapeutic agent is generally limited and the traditional combination chemotherapies frequently result in the aggravation of side effects. Herein, an amphiphilic pillararene-based self-assembled nanoparticle (APSN) composed of hydrazide-pillar[5]arene (HP5A-6C) that achieve effective co-delivery of therapeutic combinations was reported. Through integrating multitudinous macrocyclic cavities into a single nanoparticle, the APSN could co-load two antitumor drugs, cisplatin (CP) and nitrogen mustard (NM) via host-guest interactions. A serious of safety tests preliminary demonstrated that blank carrier APSN had good biocompatibility. Cytotoxicity assay verified that co-delivery system CP+NM@APSN could exert a synergistic antitumor effect at the cellular level. In vivo studies demonstrated that CP+NM@APSN could not only improve chemotherapeutic outcomes in tumor-bearing model mouse but also alleviate two medications-related side effects. These favorable findings were attributed to the formation of ternary supramolecular assembly that benefited from an enhanced permeability and retention effect. © 2024 Elsevier Science. All rights reserved.

Rational Design of Coordination Polymers Composited Hollow Multishelled Structures for Drug Delivery

Multifunctional drug delivery systems (DDS) are in high demand for effectively targeting specific cells, necessitating excellent biocompatibility, precise release mechanisms, and sustained release capabilities. The hollow multishelled structure (HoMS) presents a promising solution, integrating structural and compositional design for efficient DDS development amidst complex cellular environments. Herein, starting from a Fe-based metal-organic framework (MOF), amorphous coordination polymers (CP) composited HoMS with controlled shell numbers are fabricated by balancing the rate of MOF decomposition and shell formation. Fe-CP HoMS loaded with DOX is utilized for synergistic chemotherapy and chemodynamic therapy, offering excellent responsive drug release capability (excellent pH-triggered drug release 82% within 72 h at pH 5.0 solution with doxorubicin (DOX) loading capacity of 284 mg g-1). In addition to its potent chemotherapy attributes, Fe-CP-HoMS possesses chemodynamic therapy potential by continuously catalyzing H2O2 to generate ·OH species within cancer cells, thus effectively inhibiting cancer cell proliferation. DOX@3S-Fe-CP-HoMS, at a concentration of 12.5 µg mL-1, demonstrates significant inhibitory effects on cancer cells while maintaining minimal cytotoxicity toward normal cells. It is envisioned that CP-HoMS could serve as an effective and biocompatible platform for the advancement of intelligent drug delivery systems in the realm of cancer therapy.

Rapid synthesis of manganese dioxide nanoparticles for enhanced biocompatibility and theranostic applications

Manganese dioxide (MnO2), lauded for its biocompatibility and distinctive optical and physical characteristics, has become an indispensable material in the biomedical field, showing immense potential in disease detection, treatment, and prevention. Particularly, the ability of MnO2 nanoparticles to oxidize glutathione (GSH) to its oxidized form has positioned them as pivotal players in GSH sensing. However, conventional preparation methods, whether top-down or bottom-up, often result in nanoparticles that require multi-step processing and modification to achieve good dispersion in physiological conditions, which is both time-consuming and complex. To address this, a rapid and efficient method was developed for producing well-dispersed and stable MnO2 nanoparticles using tannic acid to reduce potassium permanganate. The polyphenolic structure of tannic acid not only facilitates the reduction process but also enhances the dispersibility of the nanoparticles in biological environments. In addition, PEG could improve the stability of MnO2 nanoparticles and also reduce their size. Moreover, we demonstrate the application of these nanoparticles in a colorimetric assay for GSH detection, leveraging their ability to react with GSH to produce Mn2+. Furthermore, these nanoparticles were utilized in a colorimetric assay for GSH detection, harnessing their reactivity with GSH to generate Mn2+. Beyond this, the MnO2 nanoparticles exhibit potential for the loading of a spectrum of molecules, including small molecules, peptides, DNA, RNA, and proteins, through electrostatic interactions, π-π stacking, and the inherent reactivity of polyphenols. This groundbreaking strategy heralds a new era for MnO2 in the realm of theranostic agent delivery, offering a promising avenue for enhancing diagnostic accuracy and therapeutic efficacy in biomedical applications.

Tröger's Base as a Potential Bridge to Type-I Photosensitizers: Mechanism and Antitumor Applications

In contrast to Type-II photodynamic therapy (PDT), Type-I PDT with less oxygen consumption has shown great potential against tumor hypoxia. However, there are limited strategies available for designing Type-I photosensitizers (PSs). Herein, we present a promising strategy for synthesizing Type-I PSs (TBC-1-TBC-4) using Tröger's base (TB) framework. The TB framework can promote intersystem crossing efficiency and create an electron-rich environment, making it the most likely site for electron transfer to O2 to generate Type-I ROS. As anticipated, TBC-1-TBC-4 demonstrates Type-I ROS generation capability and their impressive visible light-harvesting ability significantly enhances this capability. Among them, TBC-1 demonstrates outstanding biocompatibility and PDT efficiency in vitro under both normoxia and hypoxia. Furthermore, TBC-1 effectively inhibits tumor growth in vivo, with negligible side effects. This is attributed to TBC-1's efficient generation of Type-I ROS and endoplasmic reticulum targeting ability. This study thus offers useful insights into developing Type-I PSs.

Emerging Approaches in Glioblastoma Treatment: Modulating the Extracellular Matrix Through Nanotechnology

Glioblastoma's (GB) complex tumor microenvironment (TME) promotes its progression and resistance to therapy. A critical component of TME is the extracellular matrix (ECM), which plays a pivotal role in promoting the tumor's invasive behavior and aggressiveness. Nanotechnology holds significant promise for GB treatment, with the potential to address challenges posed by both the blood-brain barrier and the GB ECM. By enabling targeted delivery of therapeutic and diagnostic agents, nanotechnology offers the prospect of improving treatment efficacy and diagnostic accuracy at the tumor site. This review provides a comprehensive exploration of GB, including its epidemiology, classification, and current treatment strategies, alongside the intricacies of its TME. It highlights nanotechnology-based strategies, focusing on nanoparticle formulations such as liposomes, polymeric nanoparticles, and gold nanoparticles, which have shown promise in GB therapy. Furthermore, it explores how different emerging nanotechnology strategies modulate the ECM to overcome the challenges posed by its high density, which restricts drug distribution within GB tumors. By emphasizing the intersection of nanotechnology and GB ECM, this review underscores an innovative approach to advancing GB treatment. It addresses the limitations of current therapies, identifies new research avenues, and emphasizes the potential of nanotechnology to improve patient outcomes.

A high-valence bismuth(V) nanoplatform triggers cancer cell death and anti-tumor immune responses with exogenous excitation-free endogenous H2O2- and O2-independent ROS generation

Reactive oxygen species with evoked immunotherapy holds tremendous promise for cancer treatment but has limitations due to its dependence on exogenous excitation and/or endogenous H2O2 and O2. Here we report a versatile oxidizing pentavalent bismuth(V) nanoplatform (NaBiVO3-PEG) can generate reactive oxygen species in an excitation-free and H2O2- and O2-independent manner. Upon exposure to the tumor microenvironment, NaBiVO3-PEG undergoes continuous H+-accelerated hydrolysis with •OH and 1O2 generation through electron transfer-mediated BiV-to-BiIII conversion and lattice oxygen transformation. The simultaneous release of sodium counterions after endocytosis triggers caspase-1-mediated pyroptosis. NaBiVO3-PEG intratumorally administered initiates robust therapeutic efficacies against both primary and distant tumors and activates systemic immune responses to combat tumor metastasis. NaBiVO3-PEG intravenously administered can efficiently accumulate at the tumor site for further real-time computed tomography monitoring, immunotherapy, or alternative synergistic immune-radiotherapy. Overall, this work offers a nanomedicine based on high-valence bismuth(V) nanoplatform and underscores its great potential for cancer immunotherapy.

Mass production of ultrasmall Mn3O4 nanoparticles for glutathione responsive off-on T 1/T 2 switching magnetic resonance imaging and tumor theranostics

Individual theranostics with an integrated multifunction holds considerable promise for clinical application compared with multicomponent regimes. Mn3O4 nanoparticles with an ultrasmall size (4 nm) and mass production capability were developed with dual function of integrated tumor magnetic resonance imaging (MRI) and therapy. The high valence state of Mn3O4 nanocrystals enables a sensitive reaction with the glutathione (GSH) molecule and favorable decomposition ability, which further induces a unique, favorable, variable T 1 turn-off and T 2 turn-on MRI property. In addition, ultrasmall Mn3O4 nanoparticles reacted with high-level GSH in the tumor microenvironment induces responsive and enhanced variable T 1- and T 2-MRI imaging capability for accurate cancer diagnosis. Moreover, the synthesized ultrasmall Mn3O4 nanoparticles exhibit considerable ferroptosis effect towards tumor cells and excellent in vivo biocompatibility, thus indicating promising effective cancer treatment application. The developed ultrasmall Mn3O4 nanoparticles with integrated dual functions of GSH-responsive variable T 1 and T 2 MRI imaging effects and ferroptosis capability show promising potential as a candidate for tumor theranostics in clinical applications.

Targeted nanoprobe for magnetic resonance imaging-guided enhanced antitumor via synergetic photothermal/immunotherapy

Synergistic photothermal/immunotherapy has garnered significant attention for its potential to enhance tumor therapeutic outcomes. However, the fabrication of an intelligent system with a simple composition that simultaneously exerts photothermal/immunotherapy effect and imaging guidance function still remains a challenge. Herein, a glutathione (GSH)-responsive theranostic nanoprobe, named HA-MnO2/ICG, was elaborately constructed by loading photothermal agent (PTA) indocyanine green (ICG) onto the surface of hyaluronic acid (HA)-modified manganese dioxide nanosheets (HA-MnO2) for magnetic resonance (MR) imaging-guided synergetic photothermal/immuno-enhanced therapy. In this strategy, HA-MnO2 nanosheets were triggered by the endogenous GSH in tumor microenvironment to generate Mn2+ for MR imaging, where the longitudinal relaxation rate of HA-MnO2/ICG was up to 14.97 mM-1s-1 (∼24 times than that found in a natural environment), demonstrating excellent intratumoral MR imaging. Moreover, the HA-MnO2/ICG nanoprobe demonstrates remarkable photothermal therapy (PTT) efficacy, generating sufficient heat to induce immunogenic cell death (ICD) within tumor cells. Meanwhile the released Mn2+ ions from the nanosheets function as potent immune adjuvants, amplifying the immune response against cancer. In vivo experiments validated that HA-MnO2/ICG-mediated PTT was highly effective in eradicating primary tumors, while simultaneously enhancing immunogenicity to prevent the growth of distal metastasis. This hybrid HA-MnO2/ICG nanoprobe opened new avenues in the design of MR imaging-monitored PTT/immuno-enhanced synergistic therapy for advanced cancer.

Intelligent Hierarchical Targeting Near-Infrared Persistent Luminescence Nanosystem for Improved Nuclear Delivery and Simultaneous Visualization/Therapy of EBV-Associated Cancer

Epstein-Barr nuclear antigen 1 (EBNA1), a sequence-specific DNA binding protein of Epstein-Barr virus (EBV), is essential for viral genome replication and maintenance and is therefore an attractive target for the therapeutic intervention of EBV-associated cancers. Several EBNA1-specific inhibitors have demonstrated the ability to block EBNA1 function in vitro, but practical delivery strategies for these inhibitors in vivo are still lacking. Here, we report an intelligent hierarchical targeting theranostic nanosystem (denoted as mZGOCS@MnO2-P5) that integrates an azide (N3) terminal dual-targeting peptide (N3-P5), a tumor microenvironment-responsive degradable MnO2 nanosheet, and a mesoporous ZnGa2O4:Cr3+, Sn4+ near-infrared persistent luminescence (NIR-PL) nanosphere (mZGOCS). In our design, mZGOCS@MnO2-P5 enables primarily targeting of the EBV-specific oncoprotein LMP1 (an EBV-encoded transmembrane protein) via the LMP1 targeting motif within P5. Once internalized into cells, the MnO2 nanosheet would be degraded in the acidic and reducing tumor microenvironment, simultaneously releasing P5 and recovering the NIR-PL of ZnGa2O4:Cr3+, Sn4+ initially quenched by the MnO2 nanosheet, thereby providing an autofluorescence interference-free NIR-PL imaging signal for monitoring the delivery efficacy of P5. The released P5 can secondarily target EBNA1 via the EBNA1 binding motif, blocking its function and thus inhibiting the growth of EBV-positive tumors. The feasibility of our developed hierarchical targeting theranostic nanosystem is well demonstrated both in vitro and in vivo, highlighting the huge translational potential of mZGOCS@MnO2-P5 in EBV-associated cancer therapy.

Oxygen/Nitric Oxide Dual-Releasing Nanozyme for Augmenting TMZ-Mediated Apoptosis and Necrosis

Glioblastoma multiforme (GBM) is the most common and aggressive malignant brain tumor, with a poor prognosis. Temozolomide (TMZ) represents the standard chemotherapy for GBM but has limited efficacy due to poor targeting and a hypoxic tumor microenvironment (TME). To address these challenges, we developed a dual-gas-releasing, cancer-cell-membrane-camouflaged nanoparticle to deliver TMZ. This nanoceria, camouflaged with a cancer cell membrane (CCM-CeO2), targets explicitly GBM cells and accumulates in lysosomes, triggering the rapid release of TMZ. Additionally, CCM-CeO2 could release oxygen (O2) and nitric oxide (NO) in response to the TME. Synthesized using d-arginine, catalytic nanoceria could decompose excessive hydrogen peroxide (H2O2) in the TME to produce O2, while d-arginine could nonenzymatically react with H2O2 to generate NO. CCM-CeO2 could penetrate GBM spheroids to a depth of 148.3 ± 31 μm, with the O2 and NO produced, reducing HIF-1α protein expression. When loaded with TMZ, CCM-CeO2 could increase the intracellular ROS produced by TMZ, leading to lysosome membrane permeabilization and notably augmented apoptosis and necrosis in GBM cells. An in vitro antitumor assay using spheroids showed that CCM-CeO2 reduced the IC50 value of TMZ from 174.5 to 42.6 μg/mL, likely due to the catalase-like activity of nanoceria. These results suggest that alleviating hypoxia and increasing ROS produced by chemotherapeutics could be an effective therapeutic strategy for treating GBM.

Self-Regenerating Photothermal Agents for Tandem Photothermal and Thermodynamic Tumor Therapy

Small molecule-based photothermal agents (PTAs) hold promising future for photothermal therapy; however, unexpected inactivation exerts negative impacts on their application clinically. Herein, a self-regenerating PTA strategy is proposed by integrating 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) with a thermodynamic agent (TDA) 2,2'-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH). Under NIR laser, the photothermal effect of ABTS•+ accelerates the production of alkyl radicals by AIPH, which activates the regeneration of ABTS•+, thus creating a continuous positive feedback loop between photothermal and thermodynamic effects. The combination of ABTS•+ regeneration and alkyl radical production leads to the tandem photothermal and thermodynamic tumor therapy. In vitro and in vivo experiments confirm that the synergistic action of thermal ablation, radical damage, and oxidative stress effectively realizes tumor suppression. This work offers a promising approach to address the unwanted inactivation of PTAs and provides valuable insights for optimizing combination therapy.

Poria cocos polysaccharide-honeycomb manganese oxide nanoparticles as a vaccine adjuvant to induce potent immune responses

As indispensable components of vaccines, adjuvants play a critical role in inducing potent immune responses. In our previous study, we isolated and purified a water-soluble polysaccharide from Poria cocos (PCP), and found that the PCP had the potential to act as an immunostimulant to induce a balanced Th1/Th2 immune response. However, the PCP showed effective immunomodulatory activity only at high concentrations. Herein, we prepared a novel and biodegradable adjuvant system (PCP-hMnOx), in which the PCP was loaded onto the honeycomb manganese oxide nanoparticles (hMnOx). The developed PCP-hMnOx adjuvant system not only acted as an immunostimulant, but also as a delivery system to enhance antigen uptake by antigen-presenting cells (APCs), stimulate the activation of APCs and facilitate the formation of germinal center in draining lymph nodes. Furthermore, the PCP-hMnOx adjuvant system facilitated the antibody production, the activation of CD4+ and CD8+ T cells, and the generation of IFN-γ, thus inducing a robust and durable immune response with a balanced Th1/Th2 response in comparison to commercial alum adjuvant. Our results demonstrated that the PCP-hMnOx adjuvant system improved the immunomodulatory activity of the PCP, and had the potential to provide a simple, safe, and efficient nanoparticles-based strategy to induce potent immune responses.