Carbon-dot-supported atomically dispersed gold as a mitochondrial oxidative stress amplifier for cancer treatment

Mitochondria-mediated self-cycling nanoreactor enabling uninterrupted oxidative damage for enhanced chemodynamic therapy

Chemodynamic therapy (CDT), which employs intracellular H2O2 to produce toxic hydroxyl radicals to kill cancer cells, has received great attention due to its specificity to tumors. However, the relatively insufficient endogenous H2O2 and the short-lifetime and limited diffusion distance of •OH compromise the therapeutic efficacy of CDT. Mitochondria, which play crucial roles in oncogenesis, are highly vulnerable to elevated oxidative stress. Herein, we constructed a mitochondria-mediated self-cycling system to achieve high dose of •OH production through continuous H2O2 supply. Cinnamaldehyde (CA), which can elevate H2O2 level in the mitochondria, was loaded in Cu(II)-containing metal organic framework (MOF), termed as HKUST-1. After actively targeting mitochondria, the intrinsic H2O2 in mitochondria of cancer cells could induce degradation of MOF, releasing the initial free CA. The released CA further triggered the upregulation of endogenous H2O2, resulting in the subsequent adequate release of CA and the final burst growth of H2O2. The cycle process greatly promoted the Fenton-like reaction between Cu2+ and H2O2 and induced long-term high oxidative stress, achieving enhanced chemodynamic therapy. In a word, we put forward an efficient strategy for enhanced chemodynamic therapy.

Strategic disruption of cancer's powerhouse: precise nanomedicine targeting of mitochondrial metabolism

Mitochondria occupy a central role in the biology of most eukaryotic cells, functioning as the hub of oxidative metabolism where sugars, fats, and amino acids are ultimately oxidized to release energy. This crucial function fuels a variety of cellular activities. Disruption in mitochondrial metabolism is a common feature in many diseases, including cancer, neurodegenerative conditions and cardiovascular diseases. Targeting tumor cell mitochondrial metabolism with multifunctional nanosystems emerges as a promising strategy for enhancing therapeutic efficacy against cancer. This review comprehensively outlines the pathways of mitochondrial metabolism, emphasizing their critical roles in cellular energy production and metabolic regulation. The associations between aberrant mitochondrial metabolism and the initiation and progression of cancer are highlighted, illustrating how these metabolic disruptions contribute to oncogenesis and tumor sustainability. More importantly, innovative strategies employing nanomedicines to precisely target mitochondrial metabolic pathways in cancer therapy are fully explored. Furthermore, key challenges and future directions in this field are identified and discussed. Collectively, this review provides a comprehensive understanding of the current state and future potential of nanomedicine in targeting mitochondrial metabolism, offering insights for developing more effective cancer therapies.

ROS mediated Cu[Fe(CN)5NO] nanoparticles for triple negative breast cancer: A detailed study in preclinical mouse model

Triple negative breast cancer (TNBC) is an aggressive form of tumor, more prevalent in younger women resulting in poor survival rate (2nd in cancer deaths) because of its asymptomatic existence. The most popular and convenient approach for the treatment of TNBC is chemotherapy which is associated with several limitations. Considering the importance of nanotechnology in health care system, in the present manuscript, we have designed and developed a simple, efficient, cost effective, and ecofriendly method for the synthesis of copper nitroprusside analogue nanoparticles (Cu[Fe(CN)5NO] which is abbreviated as CuNPANP that may be the potential anti-cancer nanomedicine for the treatment of TNBC. Copper (present in CuNPANP) is used because of its affordability, nutritional value and various biomedical applications. The CuNPANP are thoroughly characterized using several analytical techniques. The in vitro cell viability (in normal cells) and the ex vivo hemolysis assay reveal the biocompatible nature of CuNPANP. The anti-cancer activity of the CuNPANP is established in TNBC cells (MDA-MB-231 and 4T1) through several in vitro assays along with plausible mechanisms. The intraperitoneal administration of CuNPANP in orthotopic breast tumor model by transplanting 4T1 cells into the mammary fat pad of BALB/c mouse significantly inhibits the growth of breast carcinoma as well as increases the survival time of tumor-bearing mice. These results altogether potentiate the anti-cancer efficacy of CuNPANP as a smart therapeutic nanomedicine for treating TNBC in near future after bio-safety evaluation in large animals.

White light powered antimicrobial nanoagents for triple photothermal, chemodynamic and photodynamic based sterilization

Antibacterial nanoagents have been increasingly developed due to their favorable biocompatibility, cost-effective raw materials, and alternative chemical or optical properties. Nevertheless, there is still a pressing need for antibacterial nanoagents that exhibit outstanding bacteria-binding capabilities and high antibacterial efficiency. In this study, we constructed a multifunctional cascade bioreactor (GCDCO) as a novel antibacterial agent. This involved incorporating carbon dots (CDs), cobalt sulfide quantum dots (CoSx QDs), and glucose oxidase (GOx) to enhance bacterial inhibition under sunlight irradiation. The GCDCO demonstrated highly efficient antibacterial capabilities attributed to its favorable photothermal properties, photodynamic activity, as well as the synergistic effects of hyperthermia, glucose-augmented chemodynamic action, and additional photodynamic activity. Within this cascade bioreactor, CDs played the role of a photosensitizer for photodynamic therapy (PDT), capable of generating ˙O2- even under solar light irradiation. The CoSx QDs not only functioned as a catalytic component to decompose hydrogen peroxide (H2O2) and generate hydroxyl radicals (˙OH), but they also served as heat generators to enhance the Fenton-like catalysis process. Furthermore, GOx was incorporated into this cascade bioreactor to internally supply H2O2 by consuming glucose for a Fenton-like reaction. As a result, GCDCO could generate a substantial amount of reactive oxygen species (ROS), leading to a significant synergistic effect that greatly induced bacterial death. Furthermore, the in vitro antibacterial experiment revealed that GCDCO displayed notably enhanced antibacterial activity against E. coli (99+ %) when combined with glucose under simulated sunlight, surpassing the efficacy of the individual components. This underscores its remarkable efficiency in combating bacterial growth. Taken together, our GCDCO demonstrates significant potential for use in the routine treatment of skin infections among diabetic patients.

Self-Supplied Reactive Oxygen Species-Responsive Mitoxantrone Polyprodrug for Chemosensitization-Enhanced Chemotherapy under Moderate Hyperthermia

Currently, the secondary development and modification of clinical drugs has become one of the research priorities. Researchers have developed a variety of TME-responsive nanomedicine carriers to solve certain clinical problems. Unfortunately, endogenous stimuli such as reactive oxygen species (ROS), as an important prerequisite for effective therapeutic efficacy, are not enough to achieve the expected drug release process, therefore, it is difficult to achieve a continuous and efficient treatment process. Herein, a self-supply ROS-responsive cascade polyprodrug (PMTO) is designed. The encapsulation of the chemotherapy drug mitoxantrone (MTO) in a polymer backbone could effectively reduce systemic toxicity when transported in vivo. After PMTO is degraded by endogenous ROS of the TME, another part of the polyprodrug backbone becomes cinnamaldehyde (CA), which can further enhance intracellular ROS, thereby achieving a sustained drug release process. Meanwhile, due to the disruption of the intracellular redox environment, the efficacy of chemotherapy drugs is enhanced. Finally, the anticancer treatment efficacy is further enhanced due to the mild hyperthermia effect of PMTO. In conclusion, the designed PMTO demonstrates remarkable antitumor efficacy, effectively addressing the limitations associated with MTO.

Organic-Inorganic Heterointerface-Expediting Electron Transfer Realizes Efficient Plasmonic Catalytic Sterilization via a Carbon-Dot Nanozyme

Plasmonic nanozymes bring enticing prospects for catalytic sterilization by leveraging plasmon-engendered hot electrons. However, the interface between plasmons and nanozymes as the mandatory path of hot electrons receives little attention, and the mechanisms of plasmonic nanozymes still remain to be elucidated. Herein, a plasmonic carbon-dot nanozyme (FeCG) is developed by electrostatically assembling catalytic iron-doped carbon dots (Fe-CDs) with plasmonic gold nanorods. The energy harvesting and hot-electron migration are remarkably expedited by a spontaneous organic-inorganic heterointerface holding a Fermi level-induced interfacial electric field. The accumulated hot electrons are then fully utilized by conductive Fe-CDs to boost enzymatic catalysis toward overproduced reactive oxygen species. By synergizing with localized heating from hot-electron decay, FeCG achieves rapid and potent disinfection with an antibacterial efficiency of 99.6% on Escherichia coli within 5 min and is also effective (94.2%) against Staphylococcus aureus. Our work presents crucial insights into the organic-inorganic heterointerface in advanced plasmonic biocidal nanozymes.

A Dual-Channel Ca2+ Nanomodulator Induces Intracellular Ca2+ Disorders via Endogenous Ca2+ Redistribution for Tumor Radiosensitization

Tumor cells harness Ca2+ to maintain cellular homeostasis and withstand external stresses from various treatments. Here, a dual-channel Ca2+ nanomodulator (CAP-P-NO) is constructed that can induce irreversible intracellular Ca2+ disorders via the redistribution of tumor-inherent Ca2+ for disrupting cellular homeostasis and thus improving tumor radiosensitivity. Stimulated by tumor-overexpressed acid and glutathione, capsaicin and nitric oxide are successively escaped from CAP-P-NO to activate the transient receptor potential cation channel subfamily V member 1 and the ryanodine receptor for the influx of extracellular Ca2+ and the release of Ca2+ in the endoplasmic reticulum, respectively. The overwhelming level of Ca2+ in tumor cells not only impairs the function of organelles but also induces widespread changes in the gene transcriptome, including the downregulation of a set of radioresistance-associated genes. Combining CAP-P-NO treatment with radiotherapy achieves a significant suppression against both pancreatic and patient-derived hepatic tumors with negligible side effects. Together, the study provides a feasible approach for inducing tumor-specific intracellular Ca2+ overload via endogenous Ca2+ redistribution and demonstrates the great potential of Ca2+ disorder therapy in enhancing the sensitivity for tumor radiotherapy.

Nanomedomics

Nanomaterials have attractive physicochemical properties. A variety of nanomaterials such as inorganic, lipid, polymers, and protein nanoparticles have been widely developed for nanomedicine via chemical conjugation or physical encapsulation of bioactive molecules. Superior to traditional drugs, nanomedicines offer high biocompatibility, good water solubility, long blood circulation times, and tumor-targeting properties. Capitalizing on this, several nanoformulations have already been clinically approved and many others are currently being studied in clinical trials. Despite their undoubtful success, the molecular mechanism of action of the vast majority of nanomedicines remains poorly understood. To tackle this limitation, herein, this review critically discusses the strategy of applying multiomics analysis to study the mechanism of action of nanomedicines, named nanomedomics, including advantages, applications, and future directions. A comprehensive understanding of the molecular mechanism could provide valuable insight and therefore foster the development and clinical translation of nanomedicines.

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.

Mitochondrial Fission in Nickel Nanoparticle-Induced Reproductive Toxicity: An In Vitro GC-1 Cell Study

Reproductive disorders and declining fertility rates are significant public health concerns affecting birth rates and future populations. Male infertility, often due to spermatogenesis defects, may be linked to environmental pollutants like nickel nanoparticles (Ni NPs). Ni NPs are extensively utilized across different industries. Nevertheless, their potential adverse effects cannot be overlooked. Previous studies have linked the reproductive toxicity induced by Ni NPs with disturbances in mitochondrial function. Mitochondrial division/fusion dynamics are crucial to their proper function, yet little is known about how Ni NPs perturb these dynamics and whether such perturbation contributes to the impairment of the male reproductive system. Herein, we demonstrated that the exposure of Ni NPs to the mouse-derived spermatogonia cell line (GC-1 cells) triggered DRP1-mediated mitochondrial division and the enhanced impairment of mitochondria, consequently promoting mitochondria-dependent cell apoptosis. Notably, both the mitochondrial division inhibitor (Mdivi-1) and lentiviral-transfected cells with low expression of Dnm1l-DK in these cells could mitigate the toxic effects induced by Ni NPs, pointing to the potential role of mitochondrial dynamics in Ni NP-induced reproductive toxicity. Collectively, our work contributes to the understanding of the mechanisms by which Ni NPs can impact male reproductive function and identifies mitochondrial division as a potential target for intervention.

Nanocarriers address intracellular barriers for efficient drug delivery, overcoming drug resistance, subcellular targeting and controlled release

The cellular barriers are major bottlenecks for bioactive compounds entering into cells to accomplish their biological functions, which limits their biomedical applications. Nanocarriers have demonstrated high potential and benefits for encapsulating bioactive compounds and efficiently delivering them into target cells by overcoming a cascade of intracellular barriers to achieve desirable therapeutic and diagnostic effects. In this review, we introduce the cellular barriers ahead of drug delivery and nanocarriers, as well as summarize recent advances and strategies of nanocarriers for increasing internalization with cells, promoting intracellular trafficking, overcoming drug resistance, targeting subcellular locations and controlled drug release. Lastly, the future perspectives of nanocarriers for intracellular drug delivery are discussed, which mainly focus on potential challenges and future directions. Our review presents an overview of intracellular drug delivery by nanocarriers, which may encourage the future development of nanocarriers for efficient and precision drug delivery into a wide range of cells and subcellular targets.

Photodynamic Therapy Induced Mitochondrial Targeting Strategies for Cancer Treatment: Emerging Trends and Insights

The perpetuity of cancer prevalence at a global level calls for development of novel therapeutic approaches with improved targetability and reduced adverse effects. Conventional cancer treatments have a multitude of limitations such as nonselectivity, invasive nature, and severe adverse effects. Chemotherapy is also losing its efficacy because of the development of multidrug resistance in the majority of cancers. To address these issues, selective targeting-based approaches are being explored for an effective cancer treatment. Mitochondria, being the moderator of a majority of crucial cellular pathways like metabolism, apoptosis, and reactive oxygen species (ROS) homeostasis, are an effective targeting site. Mitochondria-targeted photodynamic therapy (PDT) has arisen as a potential approach in this endeavor. By designing photosensitizers (PSs) that preferentially accumulate in the mitochondria, PDT offers a localized technique to induce cytotoxicity in cancer cells. In this review, we intend to explore the crucial principles and challenges associated with mitochondria-targeted PDT, including variability in mitochondrial function, mitochondria-specific PSs, targeted nanocarrier-based monotherapy, and combination therapies. The hurdles faced by this emerging strategy with respect to safety, optimization, clinical translation, and scalability are also discussed. Nonetheless, mitochondria-targeted PDT exhibits a significant capacity in cancer treatment, especially in combination with other therapeutic modalities. With perpetual research and technological advancements, this treatment strategy is a great addition to the arsenal of cancer treatment options, providing better tumor targetability while reducing the damage to surrounding healthy tissues. This review emphasizes the current status of mitochondria-targeted PDT, limitations, and future prospects in its pursuit of safe and efficacious cancer therapy.

Selective Manipulation of the Mitochondria Oxidative Stress in Different Cells Using Intelligent Mesoporous Silica Nanoparticles to Activate On-Demand Immunotherapy for Cancer Treatment

Herein, the vitamin K2 (VK2)/maleimide (MA) coloaded mesoporous silica nanoparticles (MSNs), functional molecules including folic acid (FA)/triphenylphosphine (TPP)/tetrapotassium hexacyanoferrate trihydrate (THT), as well as CaCO3 are explored to fabricate a core-shell-corona nanoparticle (VMMFTTC) for on-demand anti-tumor immunotherapy. After application, the tumor-specific acidic environment first decomposed CaCO3 corona, which significantly levitates the pH value of tumor tissue to convert M2 type macrophage to the antitumor M1 type. The resulting VMMFTT would then internalize in both tumor cells and macrophages via FA-assisted endocytosis and free endocytosis, respectively. These distinct processes generate different amount of VMMFTT in above two cells followed by 1) TPP-induced accumulation in the mitochondria, 2) THT-mediated effective capture of various signal ions to cut off signal transmission and further inhibit glutathione (GSH) generation, 3) ions catalyzed reactive oxygen species (ROS) production through Fenton reaction, 4) sustained release of VK2 and MA to further enhance the ROS production and GSH depletion, which caused significant apoptosis of tumor cells and additional M2-to-M1 macrophage polarization via different processes of oxidative stress. Moreover, the primary tumor apoptosis further matures surrounding immature dendritic cells and activates T cells to continuously promote the antitumor immunotherapy.

Glutaminolysis inhibition boosts photodynamic therapy to eliminate cancer stem cells

High reactive oxygen species (ROS) levels provide a therapeutic opportunity to eradicate cancer stem cells (CSCs), a population of cells responsible for tumorigenesis, progression, metastasis, and recurrence. However, enhanced antioxidant systems in this population of cells attenuate ROS-inducing therapies. Here, we developed a nanoparticle-assisted combination therapy to eliminate CSCs by employing photodynamic therapy (PDT) to yield ROS while disrupting ROS defense with glutaminolysis inhibition. Specifically, we leveraged an oleic acid-hemicyanine conjugate (CyOA) as photosensitizer, a new entity molecule HYL001 as glutaminolysis inhibitor, and a biocompatible folic acid-hydroxyethyl starch conjugate (FA-HES) as amphiphilic surfactant to construct cellular and mitochondrial hierarchical targeting nanomedicine (COHF NPs). COHF NPs inhibited glutaminolysis to reduce intracellular ROS scavengers, including glutathione (GSH) and nicotinamide adenine dinucleotide phosphate (NADPH), and to blunt oxidative phosphorylation (OXPHOS) for oxygen-conserved PDT. Compared to COLF NPs without glutaminolysis inhibitor, COHF NPs exhibited higher phototoxicity to breast cancer stem cells (BCSCs) both in vitro and in vivo. More importantly, we corroborated that marketed glutaminolysis inhibitors, such as CB839 and V9302, augment the clinically used photosensitizer (Hiporfin) for BCSCs elimination. This study develops a potent CSCs targeting strategy by combining glutaminolysis inhibition with PDT and provides significant implications for cancer therapy.

Single-Atom Catalysts Mediated Bioorthogonal Modulation of N6-Methyladenosine Methylation for Boosting Cancer Immunotherapy

Bioorthogonal reactions provide a powerful tool to manipulate biological processes in their native environment. However, the transition-metal catalysts (TMCs) for bioorthogonal catalysis are limited to low atomic utilization and moderate catalytic efficiency, resulting in unsatisfactory performance in a complex physiological environment. Herein, sulfur-doped Fe single-atom catalysts with atomically dispersed and uniform active sites are fabricated to serve as potent bioorthogonal catalysts (denoted as Fe-SA), which provide a powerful tool for in situ manipulation of cellular biological processes. As a proof of concept, the N6-methyladensoine (m6A) methylation in macrophages is selectively regulated by the mannose-modified Fe-SA nanocatalysts (denoted as Fe-SA@Man NCs) for potent cancer immunotherapy. Particularly, the agonist prodrug of m6A writer METTL3/14 complex protein (pro-MPCH) can be activated in situ by tumor-associated macrophage (TAM)-targeting Fe-SA@Man, which can upregulate METTL3/14 complex protein expression and then reprogram TAMs for tumor killing by hypermethylation of m6A modification. Additionally, we find the NCs exhibit an oxidase (OXD)-like activity that further boosts the upregulation of m6A methylation and the polarization of macrophages via producing reactive oxygen species (ROS). Ultimately, the reprogrammed M1 macrophages can elicit immune responses and inhibit tumor proliferation. Our study not only sheds light on the design of single-atom catalysts for potent bioorthogonal catalysis but also provides new insights into the spatiotemporal modulation of m6A RNA methylation for the treatment of various diseases.

Enhancing lipid peroxidation via radical chain transfer reaction for MRI guided and effective cancer therapy in mice

Lipid peroxidation (LPO), the process of membrane lipid oxidation, is a potential new form of cell death for cancer treatment. However, the radical chain reaction involved in LPO is comprised of the initiation, propagation (the slowest step), and termination stages, limiting its effectiveness in vivo. To address this limitation, we introduce the radical chain transfer reaction into the LPO process to target the propagation step and overcome the sluggish rate of lipid peroxidation, thereby promoting endogenous lipid peroxidation and enhancing therapeutic outcomes. Firstly, radical chain transfer agent (CTA-1)/Fe nanoparticles (CTA-Fe NPs-1) was synthesized. Notably, CTA-1 convert low activity peroxyl radicals (ROO·) into high activity alkoxyl radicals (RO·), creating the cycle of free radical oxidation and increasing the propagation of lipid peroxidation. Additionally, CTA-1/Fe ions enhance reactive oxygen species (ROS) generation, consume glutathione (GSH), and thereby inactivate GPX-4, promoting the initiation stage and reducing termination of free radical reaction. CTA-Fe NPs-1 induce a higher level of peroxidation of polyunsaturated fatty acids in lipid membranes, leading to highly effective treatment in cancer cells. In addition, CTA-Fe NPs-1 could be enriched in tumors inducing potent tumor inhibition and exhibit activatable T1-MRI contrast of magnetic resonance imaging (MRI). In summary, CTA-Fe NPs-1 can enhance intracellular lipid peroxidation by accelerating initiation, propagation, and inhibiting termination step, promoting the cycle of free radical reaction, resulting in effective anticancer outcomes in tumor-bearing mice.

Erythrocyte Membrane Camouflaged Nanotheranostics for Optical Molecular Imaging-Escorted Self-Oxygenation Photodynamic Therapy

Hypoxic tumor microenvironment (TME) hampers the application of oxygen (O2 )-dependent photodynamic therapy (PDT) in solid tumors. To address this problem, a biomimetic nanotheranostics (named MMCC@EM) is developed for optical molecular imaging-escorted self-oxygenation PDT. MMCC@EM is synthesized by encapsulating chlorin e6 (Ce6) and catalase (CAT) in metal-organic framework (MOF) nanoparticles with erythrocyte membrane (EM) camouflage. Based on the biomimetic properties of EM, MMCC@EM efficiently accumulates in tumor tissues. The enriched MMCC@EM achieves TME-activatable drug release, thereby releasing CAT and Ce6, and this process can be monitored through fluorescence (FL) imaging. In addition, endogenous hydrogen peroxide (H2 O2 ) will be decomposed by CAT to produce O2 , which can be reflected by the measurement of intratumoral oxygen concentration using photoacoustic (PA) imaging. Such self-oxygenation nanotheranostics effectively mitigate tumor hypoxia and improve the generation of singlet oxygen (1 O2 ). The 1 O2 disrupts mitochondrial function and triggers caspase-3-mediated cellular apoptosis. Furthermore, MMCC@EM triggers immunogenic cell death (ICD) effect, leading to an increased infiltration of cytotoxic T lymphocytes (CTLs) into tumor tissues. As a result, MMCC@EM exhibits good therapeutic effects in 4T1-tumor bearing mice under the navigation of FL/PA duplex imaging.

Glutathione Depletion-Induced ROS/NO Generation for Cascade Breast Cancer Therapy and Enhanced Anti-Tumor Immune Response

Introduction

As an effective alternative choice to traditional mono-therapy, multifunctional nanoplatforms hold great promise for cancer therapy. Based on the strategies of Fenton-like reactions and reactive oxygen species (ROS)-mediated therapy, black phosphorus (BP) nanoplatform BP@Cu2O@L-Arg (BCL) co-assembly of cuprous oxide (Cu2O) and L-Arginine (L-Arg) nanoparticles was developed and evaluated for synergistic cascade breast cancer therapy.

Methods

Cu2O particles were generated in situ on the surface of the BP nanosheets, followed by L-Arg incorporation through electrostatic interactions. In vitro ROS/nitric oxide (NO) generation and glutathione (GSH) depletion were evaluated. In vitro and in vivo anti-cancer activity were also assessed. Finally, immune response of BCL under ultrasound was investigated.

Results

Cu2O was incorporated into BP to exhaust the overexpressed intracellular GSH in cancer cells via the Fenton reaction, thereby decreasing ROS consumption. Apart from being used as biocompatible carriers, BP nanoparticles served as sonosensitizers to produce excessive ROS under ultrasound irradiation. The enhanced ROS accumulation accelerated the oxidation of L-Arg, which further promoted NO generation for gas therapy. In vitro experiments revealed the outstanding therapeutic killing effects of BCL under ultrasound via mechanisms involving GSH deletion and excessive ROS and NO generation. In vivo studies have illustrated that the nanocomplex modified the immune response by promoting macrophage and CD8+ cell infiltration and inhibiting MDSC infiltration.

Discussion

BCL nanoparticles exhibited multifunctional characteristics for GSH depletion-induced ROS/NO generation, making a new multitherapy strategy for cascade breast cancer therapy.

Nanocatalysts for modulating antitumor immunity: fabrication, mechanisms and applications

Immunotherapy harnesses the inherent immune system in the body to generate systemic antitumor immunity, offering a promising modality for defending against cancer. However, tumor immunosuppression and evasion seriously restrict the immune response rates in clinical settings. Catalytic nanomedicines can transform tumoral substances/metabolites into therapeutic products in situ, offering unique advantages in antitumor immunotherapy. Through catalytic reactions, both tumor eradication and immune regulation can be simultaneously achieved, favoring the development of systemic antitumor immunity. In recent years, with advancements in catalytic chemistry and nanotechnology, catalytic nanomedicines based on nanozymes, photocatalysts, sonocatalysts, Fenton catalysts, electrocatalysts, piezocatalysts, thermocatalysts and radiocatalysts have been rapidly developed with vast applications in cancer immunotherapy. This review provides an introduction to the fabrication of catalytic nanomedicines with an emphasis on their structures and engineering strategies. Furthermore, the catalytic substrates and state-of-the-art applications of nanocatalysts in cancer immunotherapy have also been outlined and discussed. The relationships between nanostructures and immune regulating performance of catalytic nanomedicines are highlighted to provide a deep understanding of their working mechanisms in the tumor microenvironment. Finally, the challenges and development trends are revealed, aiming to provide new insights for the future development of nanocatalysts in catalytic immunotherapy.

A cancer cell nanotherapy method based on GHz film bulk acoustic resonator and nanoscale CaO2

Sonodynamic therapy (SDT) is an emerging cancer treatment method in recent years. However, the ultrasound signal utilized for SDT is usually located at a low-frequency spectrum (<2 MHz), and in the field of SDT research, few studies have focused on the exploration and development of ultrasound frequency. Studies have shown that the GHz-level ultrasound can increase cell membrane permeability and have a negligible effect on cell vitality. Herein, we reported the study of a GHz thin film bulk acoustic resonator as an ultrasound source for synergistic treatment with nanoscale calcium peroxide (CaO2). It was discovered that this ultrasound source ultimately achieved an efficient therapeutic outcome on mouse breast cancer cell line 4T1. Such GHz-level ultrasound application in SDT is of high significance to broaden the cognition and application scope of SDT.

Intelligent Size-Switchable Iron Carbide-Based Nanocapsules with Cascade Delivery Capacity for Hyperthermia-Enhanced Deep Tumor Ferroptosis

The ferroptosis pathway is recognized as an essential strategy for tumor treatment. However, killing tumor cells in deep tumor regions with ferroptosis agents is still challenging because of distinct size requirements for intratumoral accumulation and deep tumor penetration. Herein, intelligent nanocapsules with size-switchable capability that responds to acid/hyperthermia stimulation to achieve deep tumor ferroptosis are developed. These nanocapsules are constructed using poly(lactic-co-glycolic) acid and Pluronic F127 as carrier materials, with Au-Fe2 C Janus nanoparticles serving as photothermal and ferroptosis agents, and sorafenib (SRF) as the ferroptosis enhancer. The PFP@Au-Fe2 C-SRF nanocapsules, designed with an appropriate size, exhibit superior intratumoral accumulation compared to free Au-Fe2 C nanoparticles, as evidenced by photoacoustic and magnetic resonance imaging. These nanocapsules can degrade within the acidic tumor microenvironment when subjected to laser irradiation, releasing free Au-Fe2 C nanoparticles. This enables them to penetrate deep into tumor regions and disrupt intracellular redox balance. Under the guidance of imaging, these PFP@Au-Fe2 C-SRF nanocapsules effectively inhibit tumor growth when exposed to laser irradiation, capitalizing on the synergistic photothermal and ferroptosis effects. This study presents an intelligent formulation based on iron carbide for achieving deep tumor ferroptosis through size-switchable cascade delivery, thereby advancing the comprehension of ferroptosis in the context of tumor theranostics.

Multienzyme-Like Nanozymes: Regulation, Rational Design, and Application

Nanomaterials with more than one enzyme-like activity are termed multienzymic nanozymes, and they have received increasing attention in recent years and hold huge potential to be applied in diverse fields, especially for biosensing and therapeutics. Compared to single enzyme-like nanozymes, multienzymic nanozymes offer various unique advantages, including synergistic effects, cascaded reactions, and environmentally responsive selectivity. Nevertheless, along with these merits, the catalytic mechanism and rational design of multienzymic nanozymes are more complicated and elusive as compared to single-enzymic nanozymes. In this review, the multienzymic nanozymes classification scheme based on the numbers/types of activities, the internal and external factors regulating the multienzymatic activities, the rational design based on chemical, biomimetic, and computer-aided strategies, and recent progress in applications attributed to the advantages of multicatalytic activities are systematically discussed. Finally, current challenges and future perspectives regarding the development and application of multienzymatic nanozymes are suggested. This review aims to deepen the understanding and inspire the research in multienzymic nanozymes to a greater extent.

Hydrogel design to overcome thermal resistance and ROS detoxification in photothermal and photodynamic therapy of cancer

Responsive heat resistance (by heat shock protein upregulation) and spontaneous reactive oxygen species (ROS) detoxification have been regarded as the major obstacles for photothermal/photodynamic therapy of cancer. To overcome the thermal resistance and improve ROS susceptibility in breast cancer therapy, Au ion-crosslinked hydrogels including indocyanine green (ICG) and polyphenol are devised. Au ion has been introduced for gel crosslinking (by catechol-Au3+ coordination), cellular glutathione depletion, and O2 production from cellular H2O2. ICG can generate singlet oxygen from O2 (for photodynamic therapy) and induce hyperthermia (for photothermal therapy) under the near-infrared laser exposure. (-)-Epigallocatechin gallate downregulates heat shock protein to overcome heat resistance during hyperthermia and exerts multiple anticancer functions in spite of its ironical antioxidant features. Those molecules are concinnously engaged in the hydrogel structure to offer fast gel transformation, syringe injection, self-restoration, and rheological tuning for augmented photo/chemotherapy of cancer. Intratumoral injection of multifunctional hydrogel efficiently suppressed the growth of primary breast cancer and completely eliminated the residual tumor mass. Proposed hydrogel system can be applied to tumor size reduction prior to surgery of breast cancer and the complete remission after its surgery.

Electron Lock Manipulates the Catalytic Selectivity of Nanozyme

Nanomaterials with enzyme-mimicking functions, termed nanozymes, offer attractive opportunities for biocatalysis and biomedicine. However, manipulating nanozyme selectivity poses an insurmountable hurdle. Here, we propose the concept of an energy-governed electron lock that controls electron transfer between nanozyme and substrates to achieve selectivity manipulation of enzyme-like catalysis. An electron lock can be constructed and opened, via modulating the nanozyme's electron energy to match the energy barrier of enzymatic reactions. An iron-doped carbon dot (FeCD) nanozyme with easy-to-regulate electron energy is selected as a proof of concept. Through regulating the conduction band which dominates electron energy, activatable oxidase and selective peroxidase (POD) with substrate affinity 123-fold higher than that of natural horseradish peroxidase (HRP) is achieved. Furthermore, while maintaining selectivity, FeCDs exhibit catalytic kinetics comparable to that of HRP upon transforming photons into electrons. Superior selectivity, efficient catalysis, and undetectable biotoxicity energize FeCDs as potent targeted drugs on antibiotic-resistant bacterial abscesses. An electron lock provides a robust strategy to manipulate selectivity toward advanced nanozymes.

NIR-Light-Triggered Mild-Temperature Hyperthermia to Overcome the Cascade Cisplatin Resistance for Improved Resistant Tumor Therapy

Currently, cisplatin resistance has been recognized as a multistep cascade process for its clinical chemotherapy failure. Hitherto, it remains challenging to develop a feasible and promising strategy to overcome the cascade drug resistance (CDR) issue for achieving fundamentally improved chemotherapeutic efficacy. Herein, a novel self-assembled nanoagent is proposed, which is constructed by Pt(IV) prodrug, cyanine dye (cypate), and gadolinium ion (Gd3+ ), for systematically conquering the cisplatin resistance by employing near-infrared (NIR) light activated mild-temperature hyperthermia in tumor targets. The proposed nanoagents exhibit high photostability, GSH/H+ -responsive dissociation, preferable photothermal conversion, and enhanced cellular uptake performance. In particular, upon 785-nm NIR light irradiation, the generated mild temperature of ≈ 43 °C overtly improves the cell membrane permeability and drug uptake, accelerates the disruption of intracellular redox balance, and apparently enhances the formation of Pt-DNA adducts, thereby effectively overcoming the CDR issue and achieves highly improved therapeutic efficacy for cisplatin-resistant tumor ablation.

Nanomedicine for cancer targeted therapy with autophagy regulation

Nanoparticles have unique physical and chemical properties and are currently widely used in disease diagnosis, drug delivery, and new drug development in biomedicine. In recent years, the role of nanomedical technology in cancer treatment has become increasingly obvious. Autophagy is a multi-step degradation process in cells and an important pathway for material and energy recovery. It is closely related to the occurrence and development of cancer. Because nanomaterials are highly targeted and biosafe, they can be used as carriers to deliver autophagy regulators; in addition to their favorable physicochemical properties, nanomaterials can be employed to carry autophagy inhibitors, reducing the breakdown of chemotherapy drugs by cancer cells and thereby enhancing the drug's efficacy. Furthermore, certain nanomaterials can induce autophagy, triggering oxidative stress-mediated autophagy enhancement and cell apoptosis, thus constraining the progression of cancer cells.There are various types of nanoparticles, including liposomes, micelles, polymers, metal-based materials, and carbon-based materials. The majority of clinically applicable drugs are liposomes, though other materials are currently undergoing continuous optimization. This review begins with the roles of autophagy in tumor treatment, and then focuses on the application of nanomaterials with autophagy-regulating functions in tumor treatment.

The afterglow of carbon dots shining in inorganic matrices

Carbon dots (CDs) are a new type of quasi-spherical and zero-dimension carbon nanomaterial with a diameter less than 10 nm. They exhibit a broad absorption spanning from the ultraviolet (UV) to visible light regions and inspire growing interests due to their excellent performance. In recent years, it was identified that the CDs embedded in various inorganic matrices (IMs) can effectively activate afterglow emission by suppressing the nonradiative transitions of molecules and protecting the triplet excitons of CDs, which hold broad application prospects. Herein, recent advances in CDs@IMs are reviewed in detail, and the interaction and luminescence mechanisms between CDs and IMs are also summarized. We highlight the synthetic strategies of constructing composites and the roles of IMs in facilitating the applications of CDs in diverse areas. Finally, some directions and challenges of future research in this field are proposed.

Redox-Activatable Magnetic Nanoarchitectonics for Self-Enhanced Tumor Imaging and Synergistic Photothermal-Chemodynamic Therapy

Oral squamous cell carcinoma (OSCC) is a prevalent malignancy of the head and neck region associated with high recurrence rates and poor prognosis under current diagnostic and treatment methods. The development of nanomaterials that can improve diagnostic accuracy and therapeutic efficacy is of great importance for OSCC. In this study, a redox-activatable nanoarchitectonics is designed via the construction of dual-valence cobalt oxide (DV-CO) nanospheres, which can serve as a contrast agent for magnetic resonance (MR) imaging, and exhibit enhanced transverse and longitudinal relaxivities through the release and redox of Co3+ /Co2+ in an acidic condition with glutathione (GSH), resulting in self-enhanced T1 /T2 -weighted MR contrast. Moreover, DV-CO demonstrates properties of intracellular GSH-depletion and hydroxyl radicals (•OH) generation through a Fenton-like reaction, enabling strengthened chemodynamic (CD) effect. Additionally, DV-CO displays efficient near-infrared laser-induced photothermal (PT) effect, thereby exhibiting synergistic PT-CD therapy for suppressing OSCC tumor cells. It further investigates the tumor-specific self-enhanced MR imaging of DV-CO both in subcutaneous and orthotopic OSCC mouse models, and demonstrate the therapeutic effects of DV-CO in orthotopic OSCC mouse models. Overall, the in vitro and in vivo findings highlight the excellent theranositc potentials of DV-CO for OSCC and offer new prospects for future advancement of nanomaterials.

An insight into recent developments of copper, silver and gold carbon dots: cancer diagnostics and treatment

Cancer is one of the most fatal diseases globally, however, advancement in the field of nanoscience specifically novel nanomaterials with nano-targeting of cancer cell lines has revolutionized cancer diagnosis and therapy and has thus attracted the attention of researchers of related fields. Carbon Dots (CDs)-C-based nanomaterials-have emerged as highly favorable candidates for simultaneous bioimaging and therapy during cancer nano-theranostics due to their exclusive innate FL and theranostic characteristics exhibited in different preclinical results. Recently, different transition metal-doped CDs have enhanced the effectiveness of CDs manifold in biomedical applications with minimum toxicity. The use of group-11 (Cu, Ag and Au) with CDs in this direction have recently gained the attention of researchers because of their encouraging results. This review summarizes the current developments of group-11 (Cu, Ag and Au) CDs for early diagnosis and therapy of cancer including their nanocomposites, nanohybrids and heterostructures etc. All The manuscript highlights imaging applications (FL, photoacoustic, MRI etc.) and therapeutic applications (phototherapy, photodynamic, multimodal etc.) of Cu-, Ag- and Au-doped CDs reported as nanotheranostic agents for cancer treatment. Sources of CDs and metals alogwith applications to give a comparative analysis have been given in the tabulated form at the end of manuscript. Further, future prospects and challenges have also been discussed.

In vitro and in vivo anticancer activity of novel Rh(III) and Pd(II) complexes with pyrazolopyrimidine derivatives

Six pyrazolopyrimidine rhodium(III) or palladium(II) complexes, [Rh(L1)(H2O)Cl3] (1), [Rh(L2)(CH3OH)Cl3] (2), [Rh(L3)(H2O)Cl3] (3), [Rh2(L4)Cl6]·CH3OH (4), [Rh(L5)(CH3CN)Cl3]·0.5CH3CN (5), and [Pd(L5)Cl2] (6), were synthesized and characterized. These complexes showed high cytotoxicity against six tested cancer cell lines. Most of the complexes showed higher cytotoxicity to T-24 cells in vitro than cisplatin. Mechanism studies indicated that complexes 5 and 6 induced G2/M phase cell cycle arrest through DNA damage, and induced apoptosis via endoplasmic reticulum stress response. In addition, complex 5 also induced cell apoptosis via mitochondrial dysfunction. Complexes 5 and 6 showed low in vivo toxicity and high tumor growth inhibitory activity in mouse tumor models. The inhibitory effect of rhodium complex 5 on tumor growth in vivo was more pronounced than that of palladium complex 6.

Cell-Derived N/P/S-Codoped Fluorescent Carbon Nanodots with Intrinsic Targeting Ability for Tumor-Specific Phototheranostics

Combining targeting ability, imaging function, and photothermal/photodynamic therapy into a single agent is highly desired for cancer theranostics. Herein, we developed a one-for-all nanoplatform with N/P/S-codoped fluorescent carbon nanodots (CNDs) for tumor-specific phototheranostics. The CNDs were prepared via a one-pot hydrothermal process using cancer cells as sources of carbon, nitrogen, phosphorus, and sulfur. The obtained N/P/S-codoped CNDs exhibit wide light absorption in the range of 200-900 nm and excitation-dependent emission with high photostability. Importantly, the cancer cell-derived N/P/S-codoped CNDs have outstanding biocompatibility and naturally intrinsic targeted ability for cancer cells as well as dual photothermal/photodynamic effects under 795 nm laser irradiation. Moreover, the photothermal conversion efficiency and singlet oxygen (1O2) generation efficiency were calculated to be 52 and 34%, respectively. These exceptional properties enable CNDs to act as fine theranostic agents for targeted imaging and photothermal-photodynamic synergistic therapy within the NIR therapeutic window. The CNDs prepared in this work are promising for construction as a universal tumor phototheranostic platform.

Neuroprotective Bioorthogonal Catalysis in Mitochondria Using Protein-Integrated Hydrogen-Bonded Organic Frameworks

Mitochondria-targeted bioorthogonal catalysis holds promise for controlling cell function precisely, yet achieving selective and efficient chemical reactions within organelles is challenging. In this study, we introduce a new strategy using protein-integrated hydrogen-bonded organic frameworks (HOFs) to enable synergistic bioorthogonal chemical catalysis and enzymatic catalysis within mitochondria. Utilizing catalytically active tris(4,4'-dicarboxylicacid-2,2'-bipyridyl) ruthenium(II) to self-assemble with [1,1'-biphenyl]-4,4'-biscarboximidamide, we synthesized nanoscale RuB-HOFs that exhibit high photocatalytic reduction activity. Notably, RuB-HOFs efficiently enter cells and preferentially localize to mitochondria, where they facilitate bioorthogonal photoreduction reactions. Moreover, we show that RuB-HOFs encapsulating catalase can produce hydrogen sulfide (H2 S) in mitochondria through photocatalytic reduction of pro-H2 S and degrade hydrogen peroxide through enzymatic catalysis simultaneously, offering a significant neuroprotective effect against oxidative stress. Our findings not only introduce a versatile chemical toolset for mitochondria-targeted bioorthogonal catalysis for prodrug activation but also pave the way for potential therapeutic applications in treating diseases related to cellular oxidative stress.

Photothermal nanozymes to self-augment combination cancer therapy by dual-glutathione depletion and hyperthermia/acidity-activated hydroxyl radical generation

Chemodynamic therapy (CDT) has emerged as a promising strategy for tumor treatment. Nevertheless, the low Fenton catalytic efficiency and the high concentration of glutathione (GSH) in cancer cells largely decline antitumor efficacy of CDT. To self-augment antitumor effect of the CDT by combining with photothermal therapy (PTT), the unique photothermal nanozymes that doubly depleted GSH, and generated massive hydroxyl radicals (·OH) in the hyperthermia/acidity-activated manner were developed. Through the coordination of Fe3+ ions with PEGylated chitosan (PEG-CS)-modified polydopamine (PDA) nanoparticles, the attained Fe3+@PEG-CS/PDA nanozymes showed outstanding colloidal stability, photothermal conversion efficiency and acidity-triggered Fe3+ release. By GSH-mediated valence states transition of Fe3+ ions and Michael reaction between GSH and quinone-rich PDA, the nanozymes sufficiently executed dual depletion of GSH with the elevated temperature.Under mimic tumor acidity and near-infrared (NIR) irradiation condition, the endocytosed nanozymes effectively converted intracellular H2O2 into toxic ·OH upon amplified Fenton reaction, thereby potently killing 4T1 cancer cells and RAW 264.7 cells. Importantly, the nanozymes prominently suppressed 4T1 tumor growth in vivo and metastasis of cancer cells by CDT/PTT combination therapy without significant systemic toxicity. Our study provides novel visions in design of therapeutic nanozymes with great clinical translational prospect for tumor treatment.

Rationally designed multifunctional nanoparticles as GSH-responsive anticancer drug delivery systems based on host-guest polymers derived from dextran and β-cyclodextrin

Tumor proliferation and metastasis rely on energy provided by mitochondria. The hexokinase inhibitor lonidamine (LND) could suppress the activities in mitochondria, being a potential antitumor drug. However, limited water-solubility of LND may hinder its biomedical applications. Besides, the cancer-killing effect of LND is compromised by the high level of glutathione (GSH) in cancer cells. Therefore, it is urgent to find a proper method to simultaneously deliver LND and deplete GSH as well as monitor GSH level in cancer cells. Herein, a host polymer β-cyclodextrin-polyethylenimine (β-CD-PEI) and a guest polymer dextran-5-dithio-(2-nitrobenzoic acid) (Dextran-SS-TNB) were synthesized and allowed to form LND-loaded GSH-responsive nanoparticles through host-guest inclusion complexation between β-CD and TNB as host and guest molecular moieties, respectively, which functioned as a system for simultaneous delivery of LND and -SS-TNB species into cancer cells. As a result, the delivery system could deplete GSH and elevate reactive oxygen species (ROS) level in cancer cells, further induce LND-based mitochondrial dysfunction and ROS-based immunogenic cell death (ICD), leading to a synergistic and efficient anticancer effect. In addition, -SS-TNB reacted with GSH to release TNB2-, which could be a probe with visible light absorption at 410 nm for monitoring the GSH level in the cells.

Potential Efficacy of Herbal Medicine-Derived Carbon Dots in the Treatment of Diseases: From Mechanism to Clinic

Carbon dots (CDs), a crucial component of nanomaterials, are zero-dimensional nanomaterials with carbon as the backbone structure and smaller than 10 nm. Due to their beneficial characteristics, they are widely used in biomedical fields such as biosensors, drug delivery, bio-imaging, and interactions with DNA. Interestingly, a novel type of carbon dot, generated by using herbal medicines as synthetic raw materials, has emerged as the most recent incomer in the family of CDs with the extensive growth in the number of materials selected for carbon dots synthesis. Herbal medicine-derived carbon dots (HM-CDs) have been employed in the biomedical industry, and are rapidly emerging as "modern nanomaterials" due to their unique structures and exceptional capabilities. Emerging trends suggest that their specific properties can be used in bleeding disorders, gastrointestinal disorders, inflammation-related diseases, and other common intractable diseases including cancer, menopausal syndrome, central nervous system disorders, and pain of various forms and causes. In addition, HM-CDs have been found to have organ-protective and antioxidant properties, as evidenced by extensive studies. This research provides a more comprehensive understanding of the biomedical applications of HM-CDs for the aforementioned disorders and investigates the intrinsic pharmacological activities and mechanisms of these HM-CDs to further advance their clinical applications.

Confining Prepared Ultrasmall Nanozymes Loading ATO for Lung Cancer Catalytic Therapy/Immunotherapy

Nanozymes with inherent enzyme-mimicking catalytic properties combat malignant tumor progression via catalytic therapy, while the therapeutic efficacy still needs to be improved. In this work, ultrasmall platinum nanozymes (nPt) in a confined domain of a wormlike pore channel in gold nanobipyramidal-mesoporous silica dioxide nanocomposites, producing nanozyme carriers AP-mSi with photoenhanced peroxidase ability, are innovatively synthesized. Afterward, based on the prepared AP-mSi, a lung-cancer nanozymes probe (AP-HAI) is ingeniously produced by removing the SiO2 template, modifying human serum albumin, and loading atovaquone molecules (ATO) as well as IR780. Under NIR light irradiation, inner AuP and IR780 collaborate for photothermal process, thus facilitating the peroxidase-like catalytic process of H2 O2 . Additionally, loaded ATO, a cell respiration inhibitor, can impair tumor respiration metabolism and cause oxygen retention, hence enhancing IR780's photodynamic therapy (PDT) effectiveness. As a result, IR780's PDT and nPt nanozymes' photoenhanced peroxidase-like ability endow probes a high ROS productivity, eliciting antitumor immune responses to destroy tumor tissue. Systematic studies reveal that the obvious reactive oxygen species (ROS) generation is obtained by the strategy of using nPt nanozymes and reducing oxygen consumption by ATO, which in turn enables lung-cancer synergetic catalytic therapy/immunogenic-cell-death-based immunotherapy. The results of this work would provide theoretical justification for the practical use of photoenhanced nanozyme probes.

A nanocomposite competent to overcome cascade drug resistance in ovarian cancer via mitochondria dysfunction and NO gas synergistic therapy

Ovarian cancer (OC) is one of the most common and recurring malignancies in gynecology. Patients with relapsed OC always develop "cascade drug resistance" (CDR) under repeated chemotherapy, leading to subsequent failure of chemotherapy. To overcome this challenge, amphiphiles (P1) carrying a nitric oxide (NO) donor (Isosorbide 5-mononitrate, ISMN) and high-density disulfide are synthesized for encapsulating mitochondria-targeted tetravalent platinum prodrug (TPt) to construct a nanocomposite (INP@TPt). Mechanism studies indicated that INP@TPt significantly inhibited drug-resistant cells by increasing cellular uptake and mitochondrial accumulation of platinum, depleting glutathione, and preventing apoptosis escape through generating highly toxic peroxynitrite anion (ONOO-). To better replicate the microenvironmental and histological characteristics of the drug resistant primary tumor, an OC patient-derived tumor xenograft (PDXOC) model in BALB/c nude mice was established. INP@TPt showed the best therapeutic effects in the PDXOC model. The corresponding tumor tissues contained high ONOO- levels, which were attributed to the simultaneous release of O2•- and NO in tumor tissues. Taken together, INP@TPt-based systematic strategy showed considerable potential and satisfactory biocompatibility in overcoming platinum CDR, providing practical applications for ovarian therapy.

Polyphenolic Carbon Quantum Dots with Intrinsic Reactive Oxygen Species Amplification for Two-Photon Bioimaging and In Vivo Tumor Therapy

Recent studies indicate that mitochondrial dysfunctions and DNA damage have a critical influence on cell survival, which is considered one of the therapeutic targets for cancer therapy. In this study, we demonstrated a comparative study of the effect of polyphenolic carbon quantum dots (CQDs) on in vitro and in vivo antitumor efficacy. Dual emissive (green and yellow) shape specific polyphenolic CQDs (G-CQDs and Y-CQDs) were synthesized from easily available nontoxic precursors (phloroglucinol), and the antitumor property of the as-synthesized probe was investigated as compared to round-shaped blue emissive CQDs (B-CQDs) derived from well-reported precursor citric acid and urea. The B-CQDs had a nuclei-targeting property, and G-CQDs and Y-CQDs had mitochondria-targeting properties. We have found that the polyphenol containing CQDs (at a dose of 100 μg mL-1) specifically attack mitochondria by excess accumulation, altering the metabolism, inhibiting branching pattern, imbalanced Bax/Bcl-2 homeostasis, and ultimately generating oxidative stress levels, leading to oxidative stress-induced cell death in cancer cells in vitro. We show that G-CQDs are the main cause of oxidative stress in cancer cells because of their ability to produce sufficient •OH- and 1O2 radicals, evidenced by electron paramagnetic resonance spectroscopy and a terephthalic acid test. Moreover, the near-infrared absorption properties of the CQDs were exhibited in two-photon (TP) emission, which was utilized for TP cellular imaging of cancer cells without photobleaching. The in vivo antitumor test further discloses that intratumoral injection of G-CQDs can significantly augment the treatment efficacy of subcutaneous tumors without any adverse effects on BalB/c nude mice. We believe that shape-specific polyphenolic CQD-based nanotheranostic agents have a potential role in tumor therapy, thus proving an insight on treatment of malignant cancers.

NIR-II femtosecond laser ignites MXene as photoacoustic bomb for continuous high-precision tumor blasting

Recently, photoacoustic (PA) cavitation-mediated therapy has become the focus of research owing to its advantage of inhibiting drug or radiation resistance; however, its application is limited because it relies on nanodroplets with one-time action. Herein, we demonstrate a femtosecond-laser-pumped ultrafast PA cavitation technique for highly efficient shockwave theranostics using niobium carbide (Nb2C) coated with polyvinylpyrrolidone-40000 (PVP), producing sustainable PA cavitation with non-phase-change nanoprobes, which effectively gets rid of the dependence on nanodroplets, guaranteeing multiple treatments. Under femtosecond (fs) laser irradiation, given that the thermal confinement regime could be well satisfied, the Nb2C-PVP nanosheets (NSs) were quickly heated, forming localized overheated nanospots with the temperature exceeding the phase-transition threshold of the surroundings, leading to precise cavitation and explosion at the tumor sites. The experiments at the cellular level showed the significant anti-tumor effects of this method. Notably, the mouse model experiments showed a relative tumor volume inhibition rate of more than 90%, demonstrating the high precision and good efficacy of the proposed anti-tumor method. This method provides a sustainable and highly effective strategy for PA theranostics, indicating its great potential for clinical applications.

Cu2+ -Anchored Carbon Nano-Photocatalysts for Visible Water Splitting to Boost Hydrogen Cuproptosis

Both hydrogen (H2 ) and copper ions (Cu+ ) can be used as anti-cancer treatments. However, the continuous generation of H2 molecules and Cu+ in specific sites of tumors is challenging. Here we anchored Cu2+ on carbon photocatalyst (Cu@CDCN) to allow the continuous generation of H2 and hydrogen peroxide (H2 O2 ) in tumors using the two-electron process of visible water splitting. The photocatalytic process also generated redox-active Cu-carbon centers. Meanwhile, the Cu2+ residues reacted with H2 O2 (the obstacle to the photocatalytic process) to accelerate the two-electron process of water splitting and cuprous ion (Cu+ ) generation, in which the Cu2+ residue promoted a pro-oxidant effect with glutathione through metal-reducing actions. Both H2 and Cu+ induced mitochondrial dysfunction and intracellular redox homeostasis destruction, which enabled hydrogen therapy and cuproptosis to inhibit cancer cell growth and suppress tumor growth. Our research is the first attempt to integrate hydrogen therapy and cuproptosis using metal-enhanced visible solar water splitting in nanomedicine, which may provide a safe and effective cancer treatment.

Single-atom catalysts-based catalytic ROS clearance for efficient psoriasis treatment and relapse prevention via restoring ESR1

Psoriasis is a common inflammatory disease of especially high recurrence rate (90%) which is suffered by approximately 3% of the world population. The overexpression of reactive oxygen species (ROS) plays a critical role in psoriasis progress. Here we show that biomimetic iron single-atom catalysts (FeN4O2-SACs) with broad-spectrum ROS scavenging capability can be used for psoriasis treatment and relapse prevention via related gene restoration. FeN4O2-SACs demonstrate attractive multiple enzyme-mimicking activities based on atomically dispersed Fe active structures, which are analogous to those of natural antioxidant enzymes, iron superoxide dismutase, human erythrocyte catalase, and ascorbate peroxidase. Further, in vitro and in vivo experiments show that FeN4O2-SACs can effectively ameliorate psoriasis-like symptoms and prevent the relapse with augmented efficacy compared with the clinical drug calcipotriol. Mechanistically, estrogen receptor 1 (ESR1) is identified as the core protein upregulated in psoriasis treatment through RNA sequencing and bioinformatic analysis. Together, this study provides a proof of concept of psoriasis catalytic therapy (PCT) and multienzyme-inspired bionics (MIB).

Recastable assemblies of carbon dots into mechanically robust macroscopic materials

Assembly of nanoparticles into macroscopic materials with mechanical robustness, green processability, and recastable ability is an important and challenging task in materials science and nanotechnology. As an emerging nanoparticle with superior properties, macroscopic materials assembled from carbon dots will inherit their properties and further offer collective properties; however, macroscopic materials assembled from carbon dots solely remain unexplored. Here we report macroscopic films assembled from carbon dots modified by ureido pyrimidinone. These films show tunable fluorescence inherited from carbon dots. More importantly, these films exhibit collective properties including self-healing, re-castability, and superior mechanical properties, with Young's modulus over 490 MPa and breaking strength over 30 MPa. The macroscopic films maintain original mechanical properties after several cycles of recasting. Through scratch healing and welding experiments, these films show good self-healing properties under mild conditions. Moreover, the molecular dynamics simulation reveals that the interplay of interparticle and intraparticle hydrogen bonding controls mechanical properties of macroscopic films. Notably, these films are processed into diverse shapes by an eco-friendly hydrosetting method. The methodology and results in this work shed light on the exploration of functional macroscopic materials assembled from nanoparticles and will accelerate innovative developments of nanomaterials in practical applications.

Single-atom nanozymes: classification, regulation strategy, and safety concerns

Nanozymes, nanomaterials possessing enzymatic activity, have been studied extensively by researchers. However, their complex composition, low density of active sites, and inadequate substrate selectivity have hindered the maturation and widespread acceptance of nanozymes. Single-atom nanozymes (SAzymes) with atomically dispersed active sites are leading the field of catalysis due to their exceptional performance. The maximum utilization rate of atoms, low cost, well-defined coordination structure, and active sites are the most prominent advantages of SAzymes that researchers favor. This review systematically categorizes SAzymes based on their support type and describes their specific applications. Additionally, we discuss regulation strategies for SAzyme activity and provide a comprehensive summary of biosafety challenges associated with these enzymes.

Amplification of oxidative stress by lipid surface-coated single-atom Au nanozymes for oral cancer photodynamic therapy

Single-atom nanozymes (SANs) are the latest trend in biomaterials research and promote the application of single atoms in biological fields and the realization of protein catalysis in vivo with inorganic nanoparticles. Carbon quantum dots (CDs) have excellent biocompatibility and fluorescence properties as a substrate carrying a single atom. It is difficult to break through pure-phase single-atom materials with quantum dots as carriers. In addition, there is currently no related research in the single-atom field in the context of oral cancer, especially head and neck squamous cell carcinoma. This research developed a lipid surface-coated nanozyme combined with CDs, single-atomic gold, and modified lipid ligands (DSPE-PEG) with transferrin (Tf) to treat oral squamous cell carcinoma. The study results have demonstrated that surface-modified single-atom carbon quantum dots (m-SACDs) exhibit excellent therapeutic effects and enable in situ image tracking for diagnosing and treating head and neck squamous carcinoma (HNSCC).

Gd/hafnium oxide@gold@chitosan core-shell nanoparticles as a platform for multimodal theranostics in oncology research

In the current study, we synthesized thiolated chitosan-stabilized gold-coated, gadolinium-doped hafnium oxide nanoparticles (CAuGH NPs) with the capability of acting as a multifunctional system to deliver anticancer drug doxorubicin (DOX), to enhance radiosensitization by ROS generation, and to provide magnetic resonance (MR) imaging contrast for biomedical applications.

Reactive oxygen nanobiocatalysts: activity-mechanism disclosures, catalytic center evolutions, and changing states

Benefiting from low costs, structural diversities, tunable catalytic activities, feasible modifications, and high stability compared to the natural enzymes, reactive oxygen nanobiocatalysts (RONBCs) have become dominant materials in catalyzing and mediating reactive oxygen species (ROS) for diverse biomedical and biological applications. Decoding the catalytic mechanism and structure-reactivity relationship of RONBCs is critical to guide their future developments. Here, this timely review comprehensively summarizes the recent breakthroughs and future trends in creating and decoding RONBCs. First, the fundamental classification, activity, detection method, and reaction mechanism for biocatalytic ROS generation and elimination have been systematically disclosed. Then, the merits, modulation strategies, structure evolutions, and state-of-art characterisation techniques for designing RONBCs have been briefly outlined. Thereafter, we thoroughly discuss different RONBCs based on the reported major material species, including metal compounds, carbon nanostructures, and organic networks. In particular, we offer particular insights into the coordination microenvironments, bond interactions, reaction pathways, and performance comparisons to disclose the structure-reactivity relationships and mechanisms. In the end, the future challenge and perspectives for RONBCs are also carefully summarised. We envision that this review will provide a comprehensive understanding and guidance for designing ROS-catalytic materials and stimulate the wide utilisation of RONBCs in diverse biomedical and biological applications.

Burst of hopping trafficking correlated reversible dynamic interactions between lipid droplets and mitochondria under starvation

Dynamic membrane contacts between lipid droplets (LDs) and mitochondria play key roles in lipid metabolism and energy homeostasis. Understanding the dynamics of LDs under energy stimulation is thereby crucial to disclosing the metabolic mechanism. Here, the reversible interactions between LDs and mitochondria are tracked in real-time using a robust LDs-specific fluorescent probe (LDs-Tags). Through tracking the dynamics of LDs at the single-particle level, spatiotemporal heterogeneity is revealed. LDs in starved cells communicate and integrate their activities (i.e., lipid exchange) through a membrane contact site-mediated mechanism. Thus the diffusion is intermittently alternated between active and confined states. Statistical analysis shows that the translocation of LDs in response to starvation stress is non-Gaussian, and obeys nonergodic-like behavior. These results provide deep understanding of the anomalous diffusion of LDs in living cells, and also afford guidance for rationally designing efficient transporter.

Biological interactions of polystyrene nanoplastics: Their cytotoxic and immunotoxic effects on the hepatic and enteric systems

As emerging pollutants in the environment, nanoplastics (NPs) can cross biological barriers and be enriched in organisms, posing a greatest threat to the health of livestock and humans. However, the size-dependent toxic effects of NPs in higher mammals remain largely unknown. To determine the size-dependent potential toxicities of NPs, we exposed mouse (AML-12) and human (L02) liver cell lines in vitro, and 6-week-old C57BL/6 mice (well-known preclinical model) in vivo to five different sizes of polystyrene NPs (PS-NPs) (20, 50, 100, 200 and 500 nm). We found that ultra-small NPs (20 nm) induced the highest cytotoxicity in mouse and human liver cell lines, causing oxidative stress and mitochondrial membrane potential loss on AML-12 cells. Unexpectedly in vivo, after long-term oral exposure to PS-NPs (75 mg/kg), medium NPs (200 nm) and large NPs (500 nm) induced significant hepatotoxicity, evidenced by increased oxidative stress, liver dysfunction, and lipid metabolism disorders. Most importantly, medium or large NPs generated local immunotoxic effects via recruiting and activating more numbers of neutrophils and monocytes in the liver or intestine, which potentially resulted in increased proinflammatory cytokine secretion and the tissue damage. The discrepancy in in vitro-in vivo toxic results might be attributed to the different properties of biodistribution and tissue accumulation of different sized NPs in vivo. Our study provides new insights regarding the hepatotoxicity and immunotoxicity of NPs on human and livestock health, warranting us to take immense measures to prevent these NPs-associated health damage.

Low-Temperature Photothermal Therapy Platform Based on Pd Nanozyme-Modified Hydrogenated TiO2

In photothermal treatments (PTTs), normal tissues around cancerous tumors get injured by excessive heat, whereas damaged cancer cells are easily restored by stress-induced heat shock proteins (HSPs) at low temperatures. Therefore, to achieve a unique tumor microenvironment (TME), it is imperative to increase PTT efficiency and reduce normal tissue injury by adopting appropriate reactive oxygen species (ROS) and lipid peroxides (LPO) cross-linked with HSPs. In the present research, a potential strategy for mild photothermal treatments (mPTTs) was proposed by initiating localized catalytic chemical reactions in TME based on Pd nanozyme-modified hydrogenated TiO2 (H-TiO2@Pd). In vitro and in vivo evaluations demonstrated that H-TiO2@Pd had good peroxidase-like activities (POD), glutathione oxidase-like activities (GSHOx), and photodynamic properties and also satisfactory biocompatibility for 4T1 cells. Localized catalytic chemical reactions in H-TiO2@Pd significantly depleted GSH to downregulate the protein expression of GPX4 and promoted the accumulation of LPO and ROS, which consumed HSP70 or inhibited its function in 4T1 cells. Hence, the as-constructed low-temperature photothermal therapeutic platform based on Pd nanozyme-modified H-TiO2 can be a promising candidate to develop a safe and effective mPTT for cancer treatments.

Smart Nanoplatform for Visualizing Hydrogen Sulfide and Amplifying Oxidative Stress to Tumor Apoptosis

Oxidative stress is involved in various signaling pathways and serves a key role in inducing cell apoptosis. Therefore, it is significant to monitor oxidative stress upon drug release for the assessment of therapeutic effects in cancer cells. Herein, a glutathione (GSH)-responsive surface-enhanced Raman scattering (SERS) nanoplatform is proposed for ultra-sensitively monitoring the substance related with oxidative stress (hydrogen sulfide, H2S), depleting reactive sulfur species and releasing anticancer drugs to amplify oxidative stress for tumor apoptosis. The Au@Raman reporter@Ag (Au@M@Ag) nanoparticles, where a 4-mercaptobenzonitrile molecule as a Raman reporter was embedded between layers of gold and silver to obtain sensitive SERS response, were coated with a covalent organic framework (COF) shell to form a core-shell structure (Au@M@Ag@COFs) as the SERS nanoplatform. The COF shell loading doxorubicin (DOX) of Au@M@Ag@COFs exhibited the GSH-responsive degradation capacity to release DOX, and its Ag layer as the sensing agent was oxidized to Ag2S by H2S to result in its prominent changes in SERS signals with a low detection limit of 0.33 nM. Moreover, the releasing DOX can inhibit the generation of H2S to promote the production of reactive oxygen species, and the depletion of reactive sulfur species (GSH and H2S) in cancer cells can further enhance the oxidative stress to induce tumor apoptosis. Overall, the SERS strategy could provide a powerful tool to monitor the dynamic changes of oxidative stress during therapeutic processes in a tumor microenvironment.