Biodegradable Biomimic Copper/Manganese Silicate Nanospheres for Chemodynamic/Photodynamic Synergistic Therapy with Simultaneous Glutathione Depletion and Hypoxia Relief

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.

Advancements in manganese complex-based MRI agents: Innovations, design strategies, and future directions

This review focuses on the advancements in manganese (Mn) complex-based magnetic resonance imaging (MRI) agents for imaging different diseases. Here we emphasize the unique redox properties of Mn to deliver innovative MRI contrast agents, including small molecules, nanoparticles (NPs), metal-organic frameworks (MOFs), and polymer hybrids. Aspects of their rational design have been discussed, including size dependence, morphology tuning, surface property enhancement, etc., while also discussing the existing challenges and potential solutions. The present work will inspire and motivate scientists to emphasize MRI-guided applications and bring clinical success in the coming years.

Nature-inspired protein mineralization strategies for nanoparticle construction: advancing effective cancer therapy

Recently, nanotechnology has shown great potential in the field of cancer therapy due to its ability to improve the stability and solubility and reduce side effects of drugs. The biomimetic mineralization strategy based on natural proteins and metal ions provides an innovative approach for the synthesis of nanoparticles. This strategy utilizes the unique properties of natural proteins and the mineralization ability of metal ions to combine nanoparticles through biomimetic mineralization processes, achieving the effective treatment of tumors. The precise control of the mineralization process between proteins and metal ions makes it possible to obtain nanoparticles with the ideal size, shape, and surface characteristics, thereby enhancing their stability and targeting ability in vivo. Herein, initially, we analyze the role of protein molecules in biomineralization and comprehensively review the functions, properties, and applications of various common proteins and metal particles. Subsequently, we systematically review and summarize the application directions of nanoparticles synthesized based on protein biomineralization in tumor treatment. Specifically, we discuss their use as efficient drug delivery carriers and role in mediating monotherapy and synergistic therapy using multiple modes. Also, we specifically review the application of nanomedicine constructed through biomimetic mineralization strategies using natural proteins and metal ions in improving the efficiency of tumor immunotherapy.

Tumor microenvironment activated mussel-inspired hollow mesoporous nanotheranostic for enhanced synergistic photodynamic/chemodynamic therapy

Anti-tumor therapies reliant on reactive oxygen species (ROS) as primary therapeutic agents face challenges due to a limited oxygen substrate. Photodynamic therapy (PDT) is particularly hindered by inherent hypoxia, while chemodynamic therapy (CDT) encounters obstacles from insufficient endogenous hydrogen peroxide (H2O2) levels. In this study, we engineered biodegradable tumor microenvironment (TME)-activated hollow mesoporous MnO2-based nanotheranostic agents, designated as HAMnO2A. This construct entails loading artemisinin (ART) into the cavity and surface modification with a mussel-inspired polymer ligand, namely hyaluronic acid-linked poly(ethylene glycol)-diethylenetriamine-conjugated (3,4-dihydroxyphenyl) acetic acid, and the photosensitizer Chlorin e6 (mPEG-HA-Dien-(Dhpa/Ce6)), facilitating dual-modal imaging-guided PDT/CDT synergistic therapy. In vitro experimentation revealed that HAMnO2A exhibited ideal physiological stability and enhanced cellular uptake capability via CD44-mediated endocytosis. Additionally, it was demonstrated that accelerated endo-lysosomal escape through the pH-dependent protonation of Dien. Within the acidic and highly glutathione (GSH)-rich TME, the active component of HAMnO2A, MnO2, underwent decomposition, liberating oxygen and releasing both Mn2+ and ART. This process alleviates hypoxia within the tumor region and initiates a Fenton-like reaction through the combination of ART and Mn2+, thereby enhancing the effectiveness of PDT and CDT by generating increased singlet oxygen (1O2) and hydroxyl radicals (•OH). Moreover, the presence of Mn2+ ions enabled the activation of T1-weighted magnetic resonance imaging. In vivo findings further validated that HAMnO2A displayed meaningful tumor-targeting capabilities, prolonged circulation time in the bloodstream, and outstanding efficacy in restraining tumor growth while inducing minimal damage to normal tissues. Hence, this nanoplatform serves as an efficient all-in-one solution by facilitating the integration of multiple functions, ultimately enhancing the effectiveness of tumor theranostics.

Manganese-induced Photothermal-Ferroptosis for synergistic tumor therapy

Ferroptosis-related tumor therapy based on nanomedicines has recently gained significant attention. However, the therapeutic performance is still hindered by the tumor's physical barriers such as the fibrotic tumor matrix and elevated interstitial fluid pressure, as well as chemical barriers like glutathione (GSH) overabundance. These physicochemical barriers impede the bioavailability of nanomedicines and compromise the therapeutic efficacy of lipid reactive oxygen species (ROS). Thus, this study pioneers a manganese-mediated overcoming of physicochemical barriers in the tumor microenvironment using organosilica-based nanomedicine (MMONs), which bolsters the synergy of photothermal-ferroptosis treatment. The MMONs display commendable proficiency in overcoming tumor physical barriers, due to their MnO2-mediated shape-morphing and softness-transformation ability, which facilitates augmented cellular internalization, enhanced tumor accumulation, and superior drug penetration. Also, the MMONs possess excellent capability in chemical barrier overcoming, including MnO2-mediated dual GSH clearance and enhanced ROS generation, which facilitates ferroptosis and heat shock protein inhibition. Notably, the resulting integration of physical and chemical barrier overcoming leads to amplified photothermal-ferroptosis synergistic tumor therapy both in vitro and in vivo. Accordingly, the comparative proteomic analysis has identified promoted ferroptosis with a transient inhibitory response observed in the mitochondria. This research aims to improve treatment strategies to better fight the complex defenses of tumors.

Disrupting redox homeostasis for tumor therapy based on PDT/chemo/ferroptosis therapeutic hybrid liposomes

Synergistic photodynamic therapy (PDT) with other therapeutic modalities can enhance the therapeutic efficacy of tumor treatment and reduce the adverse effects associated with drug leakage and off-target accumulation. However, shaping combined strategies for synergistic therapy remains challenging. Herein, we developed versatile hybrid liposomes self-assembled from Ce6-lipid conjugates and loaded with the chemo drug doxorubicin (DOX) and ferroptosis inducer Fe3O4 nanoparticles for synergistic PDT/chemo/ferroptosis therapy. Abundant ROS are generated by PDT upon 650 nm light irradiation, Fe3O4-mediated Fenton reaction, and DOX-induced apoptosis. Furthermore, amplifying oxidative stress in cancer cells to disrupt cellular redox homeostasis could accelerate tumor cell death through oxidative damage to lipids, proteins, and DNA. Overall, this work highlights liposome-based therapeutic nanoformulations, thus offering a breakthrough redox homeostasis-based synergistic PDT/chemo/ferroptosis therapy for lung cancer.

Biocompatible Copper-Based Nanocomposites for Combined Cancer Therapy

Copper (Cu) and Cu-based nanomaterials have received tremendous attention in recent years because of their unique physicochemical properties and good biocompatibility in the treatment of various diseases, especially cancer. To date, researchers have designed and fabricated a variety of integrated Cu-based nanocomplexes with distinctive nanostructures and applied them in cancer therapy, mainly including chemotherapy, radiotherapy (RT), photothermal therapy (PTT), chemodynamic therapy (CDT), photodynamic therapy (PDT), cuproptosis-mediated therapy, etc. Due to the limited effect of a single treatment method, the development of composite diagnostic nanosystems that integrate chemotherapy, PTT, CDT, PDT, and other treatments is of great significance and offers great potential for the development of the next generation of anticancer nanomedicines. In view of the rapid development of Cu-based nanocomplexes in the field of cancer therapy, this review focuses on the current state of research on Cu-based nanomaterials, followed by a discussion of Cu-based nanocomplexes for combined cancer therapy. Moreover, the current challenges and future prospects of Cu-based nanocomplexes in clinical translation are proposed to provide some insights into the design of integrated Cu-based nanotherapeutic platforms.

Fe3O4-Incorporated Metal-Organic Framework for Chemo/Ferroptosis Synergistic Anti-Tumor via the Enhanced Chemodynamic Therapy

Metal-organic framework (MOF)-based drug delivery nanomaterials for cancer therapy have attracted increasing attention in recent years. Here, an enhanced chemodynamic anti-tumor therapy strategy by promoting the Fenton reaction by using core-shell zeolitic imidazolate framework-8 (ZIF-8)@Fe3O4 as a therapeutic platform is proposed. Carboxymethyl cellulose (CMC) is used as a stabilizer of Fe3O4, which is then decorated on the surface of ZIF-8 via the electrostatic interaction and serves as an efficient Fenton reaction trigger. Meanwhile, the pH-responsive ZIF-8 scaffold acts as a container to encapsulate the chemotherapeutic drug doxorubicin (DOX). The obtained DOX-ZIF-8@Fe3O4/CMC (DZFC) nanoparticles concomitantly accelerate DOX release and generate more hydroxyl radicals by targeting the lysosomes in cancer cells. In vitro and in vivo studies verify that the DZFC nanoparticles trigger glutathione peroxidase 4 (GPX4)-dependent ferroptosis via the activation of the c-Jun N-terminal kinases (JNK) signaling pathway, following to achieve the chemo/ferroptosis synergistic anti-tumor efficacy. No marked toxic effects are detected during DZFC treatment in a tumor-bearing mouse model. This composite nanoparticle remarkably suppresses the tumor growth with minimized systemic toxicity, opening new horizons for the next generation of theragnostic nanomedicines.

Recent Progress in Anti-Tumor Nanodrugs Based on Tumor Microenvironment Redox Regulation

The growth state of tumor cells is strictly affected by the specific abnormal redox status of the tumor microenvironment (TME). Moreover, redox reactions at the biological level are also central and fundamental to essential energy metabolism reactions in tumors. Accordingly, anti-tumor nanodrugs targeting the disruption of this abnormal redox homeostasis have become one of the hot spots in the field of nanodrugs research due to the effectiveness of TME modulation and anti-tumor efficiency mediated by redox interference. This review discusses the latest research results of nanodrugs in anti-tumor therapy, which regulate the levels of oxidants or reductants in TME through a variety of therapeutic strategies, ultimately breaking the original "stable" redox state of the TME and promoting tumor cell death. With the gradual deepening of study on the redox state of TME and the vigorous development of nanomaterials, it is expected that more anti-tumor nano drugs based on tumor redox microenvironment regulation will be designed and even applied clinically.

A Versatile Cryomicroneedle Patch for Traceable Photodynamic Therapy

Photodynamic therapy (PDT) continues to encounter multifarious hurdles, stemming from the ineffectual preservation and delivery system of photosensitizers, the dearth of imaging navigation, and the antioxidant/hypoxic tumor microenvironment. Herein, a versatile cryomicroneedle patch (denoted as CMN-CCPH) is developed for traceable PDT. The therapeutic efficacy is further amplified by catalase (CAT)-induced oxygen (O2) generation and Cu2+-mediated glutathione (GSH) depletion. The CMN-CCPH is composed of cryomicroneedle (CMN) as the vehicle and CAT-biomineralized copper phosphate nanoflowers (CCP NFs) loaded with hematoporphyrin monomethyl ether (HMME) as the payload. Importantly, the bioactive function of HMME and CAT can be optimally maintained under the protection of CCPH and CMN for a duration surpassing 60 days, leading to bolstered bioavailability and notable enhancements in PDT efficacy. The in vivo visualization of HMME and oxyhemoglobin saturation (sO2) monitored by fluorescence (FL)/photoacoustic (PA) duplex real-time imaging unveils the noteworthy implications of CMN-delivered CCPH for intratumoral enrichment of HMME and O2 with reduced systemic toxicity. This versatile CMN patch demonstrates distinct effectiveness in neoplasm elimination, underscoring its promising clinical prospects.

FeNi-MIL-88B-based electrochemiluminescence immunosensor for ultra-sensitive detection of CD44 protein via dual-quenching strategy

BACKGROUND

Cluster of Differentiation 44 (CD44) is considered an important biomarker for various cancers, and achieving highly sensitive detection of CD44 is crucial, which plays a significant role in tumor invasion and metastasis, providing essential information for clinical tumor diagnosis. Commonly used methods for analysis include fluorescence spectroscopy (FL), photoelectrochemical analysis (PEC), electrochemical analysis (EC), and commercial ELISA kits. Although these methods offer high sensitivity, they can be relatively complex to perform experimentally. Electrochemiluminescence (ECL) has gained widespread research attention due to its high sensitivity, ease of operation, effective spatiotemporal control, and close to zero background signal.

RESULTS

In this work, a sandwich-type ECL immunosensor for detecting CD44 was constructed using luminol as a luminophore. In this sensing platform, bimetallic MOFs (Pd@FeNi-MIL-88B) loaded with palladium nanoparticles (Pd NPs) were used as a novel enzyme mimic, exhibiting excellent catalytic performance towards the electroreduction of H2O2. The hybrids provided a strong support platform for luminol and antibodies, significantly enhancing the initial ECL signal of luminol. Subsequently, core-shell Au@MnO2 nanocomposites were synthesised by gold nanoparticles (Au NPs) encapsulated in manganese dioxide (MnO2) thin layers, as labels. In the luminol/H2O2 system, Au@MnO2 exhibited strong light absorption in the broad UV-vis spectrum, similar to the black body effect, and the scavenging effect of Mn2+ on O2•-, which achieved the dual-quenching of ECL signal. Under the optimal experimental conditions, the immunosensor demonstrated a detection range of 0.1 pg mL-1 - 100 ng mL-1, with a detection limit of 0.069 pg mL-1.

SIGNIFICANCE

Based on Pd@FeNi-MIL-88B nanoenzymes and Au@MnO2 nanocomposites, a dual-quenching sandwich-type ECL immunosensor for the detection of CD44 was constructed. The proposed immunosensor exhibited excellent reproducibility, stability, selectivity, and sensitivity, and provided a valuable analytical strategy and technical platform for the accurate detection of disease biomarkers, and opened up potential application prospects for early clinical treatment.

Critical learning from industrial catalysis for nanocatalytic medicine

Systematical and critical learning from industrial catalysis will bring inspiration for emerging nanocatalytic medicine, but the relevant knowledge is quite limited so far. In this review, we briefly summarize representative catalytic reactions and corresponding catalysts in industry, and then distinguish the similarities and differences in catalytic reactions between industrial and medical applications in support of critical learning, deep understanding, and rational designing of appropriate catalysts and catalytic reactions for various medical applications. Finally, we summarize/outlook the present and potential translation from industrial catalysis to nanocatalytic medicine. This review is expected to display a clear picture of nanocatalytic medicine evolution.

Multi-level Reactive Oxygen Species Amplifier to Enhance Photo-/Chemo-Dynamic/Ca2+ Overload Synergistic Therapy

Reactive oxygen species (ROS)-involved photodynamic therapy (PDT) and chemodynamic therapy (CDT) hold great promise for tumor treatment. However, hypoxia, insufficient H2O2, and overexpressed glutathione (GSH) in the tumor microenvironment (TME) hinder ROS generation significantly. Herein, we reported CaO2@Cu-TCPP/CUR with O2/H2O2/Ca2+ self-supply and GSH depletion for enhanced PDT/CDT and Ca2+ overload synergistic therapy. CaO2 nanospheres were first prepared and used as templates for guiding the coordination between the carboxyl of tetra-(4-carboxyphenyl)porphine (TCPP) and Cu2+ ions as hollow CaO2@Cu-TCPP, which facilitated GSH-activated TCPP-based PDT and Cu+-mediated CDT. The hollow structure was then loaded with curcumin (CUR) to form CaO2@Cu-TCPP/CUR composites. Cu-TCPP prevented degradation of CaO2, while Cu2+ ions reacted with GSH to deplete GSH, produce Cu+ ions, and release TCPP, CaO2, and CUR. CaO2 reacted with H2O to generate O2, H2O2, and Ca2+ to achieve O2/H2O2/Ca2+ self-supply for TCPP-based PDT, Cu+-mediated CDT, and CUR-enhanced Ca2+ overload therapy. Thus, this multilevel ROS amplifier enhances synergistic therapy with fewer side effects and drug resistance.

NIR-Mediated Cu2O/Au Nanomotors for Synergistically Treating Hepatoma Carcinoma Cells

We presented a NIR-driven Janus Cu2O/Au nanomotor. The nanomotor has a truncated octahedral structure. By asymmetric Au evaporation, the light response range of Cu2O nanomotor is extended to near-infrared range, and the speed of Cu2O/Au nanomotors under NIR is significantly increased. In promoting apoptosis of hepatocellular carcinoma, except the nanotoxicity of Cu2O itself, the Au layer enhances the photothermal properties, allowing Cu2O/Au nanomotors to induce apoptosis in hepatocellular carcinoma cells by heating them. On the other hand, a Schottky barrier formed at the interface of Cu2O and Au, preventing the recombination of electrons, which makes more electrons react with biomolecules to produce toxic ROS to kill hepatocellular cells. The killing rate of hepatocellular carcinoma cells reached 87 % by the combined effect of nanotoxicity inhibition of proliferation and photothermal & photodynamic therapy (PTT & PDT). Nanomotors in combination with multiple approaches are explored as a new treatment to tumor in this article.

Oxidative stress and potential effects of metal nanoparticles: A review of biocompatibility and toxicity concerns

Metal nanoparticles (M-NPs) have garnered significant attention due to their unique properties, driving diverse applications across packaging, biomedicine, electronics, and environmental remediation. However, the potential health risks associated with M-NPs must not be disregarded. M-NPs' ability to accumulate in organs and traverse the blood-brain barrier poses potential health threats to animals, humans, and the environment. The interaction between M-NPs and various cellular components, including DNA, multiple proteins, and mitochondria, triggers the production of reactive oxygen species (ROS), influencing several cellular activities. These interactions have been linked to various effects, such as protein alterations, the buildup of M-NPs in the Golgi apparatus, heightened lysosomal hydrolases, mitochondrial dysfunction, apoptosis, cell membrane impairment, cytoplasmic disruption, and fluctuations in ATP levels. Despite the evident advantages M-NPs offer in diverse applications, gaps in understanding their biocompatibility and toxicity necessitate further research. This review provides an updated assessment of M-NPs' pros and cons across different applications, emphasizing associated hazards and potential toxicity. To ensure the responsible and safe use of M-NPs, comprehensive research is conducted to fully grasp the potential impact of these nanoparticles on both human health and the environment. By delving into their intricate interactions with biological systems, we can navigate the delicate balance between harnessing the benefits of M-NPs and minimizing potential risks. Further exploration will pave the way for informed decision-making, leading to the conscientious development of these nanomaterials and safeguarding the well-being of society and the environment.

Porphyrin Derivative with Binary Properties of Photodynamic Therapy and Water-Dependent Reversible Photoacidity Therapy for Treating Hypoxic Tumor

Porphyrin photosensitizers are the classic drugs in clinical photodynamic therapy (PDT), but the hypoxia of tumor environment and the rapid oxygen consumption of PDT severely weaken their therapeutic effect. A recently reported water-dependent reversible photoacidity therapy (W-RPAT) is O2-independence, providing a solution for the treatment of hypoxic tumors. In this work, TPP-O-PEG5, a porphyrin derivative with binary properties of PDT and W-RPAT, is designed and synthesized for the first time. The nanoparticles (NPs) of TPP-O-PEG5 encapsulated with DSPE-mPEG2000, an amphiphilic polymer approved by Food and Drug Administration, can simultaneously produce reactive oxygen species and H+ under irradiation of a 660 nm laser, and revert the H+ back under darkness, presenting strong phototoxicity to multiple tumor cell lines with no obvious difference between the IC50 values tested under normoxic (≈20% O2) and hypoxic (<0.5% O2) conditions. Excitingly, in vivo experiments show that the therapeutic effect of TPP-O-PEG5 NPs on large hypoxic tumors is better than that of NPe6, a clinical porphin PDT drug. This work provides a novel strategy for porphyrin photosensitizers to break through the limitation of hypoxic environment, and significantly improve the phototherapeutic effect on hypoxic tumors.

Gold nanoparticles decorated on MOF derived Cu5Zn8 hollow porous carbon nanocubes for magnetic resonance imaging guided tumor microenvironment-mediated synergistic chemodynamic and photothermal therapy

Combining chemodynamic therapy (CDT) with photothermal therapy (PTT) has developed as a promising approach for cancer treatment, as it enhances therapeutic efficiency through redox reactions and external laser induction. In this study, we designed metal organic framework (MOF) -derived Cu5Zn8/HPCNC through a carbonization process and decorated them with gold nanoparticles (Au@Cu5Zn8/HPCNC). The resulting nanoparticles were employed as a photothermal agent and Fenton catalyst. The Fenton reaction facilitated the conversation of Cu2+ to Cu+ through reaction with local H2O2, generating reactive hydroxyl radicals (·OH) with potent cytotoxic effects. To enhance the Fenton-like reaction and achieve combined therapy, laser irradiation of the Au@Cu5Zn8/HPCNC induced efficient photothermal therapy by generating localized heat. With a significantly increased absorption of Au@Cu5Zn8/HPCNC at 808 nm, the photothermal efficiency was determined to be 57.45 %. Additionally, Au@Cu5Zn8/HPCNC demonstrated potential as a contrast agent for magnetic resonance imaging (MRI) of cancers. Furthermore, the synergistic combination of PTT and CDT significantly inhibited tumor growth. This integrated approach of PTT and CDT holds great promise for cancer therapy, offering enhanced CDT and modulation of the tumor microenvironment (TME), and opening new avenues in the fight against cancer.

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.

Tumor targeted nanohybrid for dual stimuli responsive and NIR amplified photothermal/photo-induced thermodynamic/chemodynamic combination therapy

The combination of photodynamic (PDT) and chemodynamic therapy (CDT) for cancer treatment has gathered a lot of attention in recent years. However, its efficacy is severely limited by elevated levels of hypoxia and glutathione (GSH) in the tumor microenvironment (TME). Multifunctional nanoparticles that can help remodel the TME while facilitating PDT/CDT combination therapy are the need of the hour. To this effect, we have developed O2self-supplying, free radical generating nanohybrids that exhibit near infra-red (NIR) triggered photothermal (PTT)/photo-induced thermodynamic (P-TDT) and CDT for efficient breast cancer treatment. The surface of nanohybrids has been further modified by biointerfacing with cancer cell membrane. The biomimetic nanohybrids have been comprehensively characterized and found to exhibit high 2,2'-azobis-[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH) loading, GSH depletion, oxygen self-supply with TME responsive AIPH release. Biological activity assays demonstrate efficient cellular uptake with homotypic targeting, excellent hemo- and cytocompatibility as well as high intracellular reactive oxygen species generation with synergistic cytotoxicity against tumor cells. The multifunctional nanohybrid proposed in the present study provides an attractive strategy for achieving NIR responsive, tumor targeted PTT/P-TDT/CDT combination therapy for breast cancer treatment.

Defect-Engineered Tin Disulfide Nanocarriers as "Precision-Guided Projectile" for Intensive Synergistic Therapy

Nanoformulations with endogenous/exogenous stimulus-responsive characteristics show great potential in tumor cell elimination with minimal adverse effects and high precision. Herein, an intelligent nanotheranostic platform (denoted as TPZ@Cu-SnS2-x /PLL) for tumor microenvironment (TME) and near-infrared light (NIR) activated tumor-specific therapy is constructed. Copper (Cu) doping and the resulting sulfur vacancies can not only improve the response range of visible light but also improve the separation efficiency of photogenerated carriers and increase the carrier density, resulting in the ideal photothermal and photodynamic performance. Density functional theory calculations revealed that the introduction of Cu and resulting sulfur vacancies can induce electron redistribution, achieving favorable photogenerated electrons. After entering cells through endocytosis, the TPZ@Cu-SnS2-x /PLL nanocomposites show the pH responsivity property for the release of the TPZ selectively within the acidic TME, and the released Cu2+ can first interact with local glutathione (GSH) to deplete GSH with the production of Cu+ . Subsequently, the Cu+ -mediated Fenton-like reaction can decompose local hydrogen peroxide into hydroxyl radicals, which can also be promoted by hyperthermia derived from the photothermal effect for tumor cell apoptosis. The integration of photoacoustic/computed tomography imaging-guided NIR phototherapy, TPZ-induced chemotherapy, and GSH-elimination/hyperthermia enhanced chemodynamic therapy results in synergistic therapeutic outcomes without obvious systemic toxicity in vivo.

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.

Optimized silicate nanozymes with atomically incorporated iron and manganese for intratumoral coordination-enhanced once-for-all catalytic therapy

Although plant-derived cancer therapeutic products possess great promise in clinical translations, they still suffer from quick degradation and low targeting rates. Herein, based on the oxygen vacancy (OV)-immobilization strategy, an OV-enriched biodegradable silicate nanoplatform with atomically dispersed Fe/Mn active species and polyethylene glycol modification was innovated for loading gallic acid (GA) (noted as FMMPG) for intratumoral coordination-enhanced multicatalytic cancer therapy. The OV-enriched FMMPG nanozymes with a narrow band gap (1.74 eV) can be excited by a 650 nm laser to generate reactive oxygen species. Benefiting from the Mn-O bond in response to the tumor microenvironment (TME), the silicate skeleton in FMMPG collapses and completely degrades after 24 h. The degraded metal M (M = Fe, Mn) ions and released GA can in situ produce a stable M-GA nanocomplex at tumor sites. Importantly, the formed M-GA with strong reductive ability can transform H2O2 into the fatal hydroxyl radical, causing serious oxidative damage to the tumor. The released Fe3+ and Mn2+ can serve as enhanced contrast agents for magnetic resonance imaging, which can track the chemodynamic and photodynamic therapy processes. The work offers a reasonable strategy for a TME-responsive degradation and intratumoral coordination-enhanced multicatalytic therapy founded on bimetallic silicate nanozymes to achieve desirable tumor theranostic outcomes.

A cascade nanoplatform for intelligent response to tumor microenvironment and collaborative cancer therapy

Disulfiram (DSF), a new potential anticancer drug, has been shown to exhibit anticancer activity dependent on the formation of CuET, the chelation product of DSF with Cu2+. However, the poor stability of DSF and insufficient physiological concentration of Cu2+ hinder its practical application. To achieve the co-delivery of DSF and Cu2+ while overcoming the inefficiency of single chemotherapy, in this study, a cascade nanoplatform, DSF/Ce6@ZIF-8@CuO2, was constructed by encapsulating DSF and chlorin e6 (Ce6, a photosensitizer) in zeolite imidazole framework-8 (ZIF-8, a nanocarrier) and then loading CuO2, which self-supplied H2O2/O2, onto DSF/Ce6@ZIF-8. By triggering the response of DSF/Ce6@ZIF-8@CuO2 to the acidic tumor microenvironment, encapsulated DSF, Ce6 and CuO2 were released to achieve multimodal synergistic treatment with enhanced DSF chemotherapy and chemodynamic/photodynamic therapy (CDT/PDT). In vitro and animal studies indicated that the designed DSF/Ce6@ZIF-8@CuO2 has strong tumor-inhibitory effects and provides a promising paradigm for designing smart nanoplatforms.

Metformin-Mediated Fast Charge-Reversal Nanohybrid for Deep Penetration Piezocatalysis-Augmented Chemodynamic Immunotherapy of Cancer

Immune checkpoint blockade (ICB) therapy still suffers from insufficient immune response and adverse effect of ICB antibodies. Chemodynamic therapy (CDT) has been demonstrated to be an effective way to synergize with ICB therapy. However, a low generation rate of reactive oxygen species and poor tumor penetration of CDT platforms still decline the immune effects. Herein, a charge-reversal nanohybrid Met@BF containing both Fe3O4 and BaTiO3 nanoparticles in the core and Metformin (Met) on the surface was fabricated for tumor microenvironment (TME)- and ultrasound (US)-activated piezocatalysis-chemodynamic immunotherapy of cancer. Interestingly, Met@BF had a negative charge in blood circulation, which was rapidly changed into positive when exposed to acidic TME attributed to quaternization of tertiary amine in Met, facilitating deep tumor penetration. Subsequently, with US irradiation, Met@BF produced H2O2 based on piezocatalysis of BaTiO3, which greatly enhanced the Fenton reaction of Fe3O4, thus boosting robust antitumor immune response. Furthermore, PD-L1 expression was inhibited by the local released Met to further augment the antitumor immune effect, achieving effective inhibitions for both primary and metastatic tumors. Such a combination of piezocatalysis-enhanced chemodynamic therapy and Met-mediated deep tumor penetration and downregulation of PD-L1 provides a promising strategy to augment cancer immunotherapy.

Different Valence States of Copper Ion Delivery against Triple-Negative Breast Cancer

Different valence states of copper (Cu) ions are involved in complicated redox reactions in vivo, which are closely related to tumor proliferation and death pathways, such as cuproptosis and chemodynamic therapy (CDT). Cu ion mediated Fenton-like reagents induced tumor cell death which presents compelling attention for the CDT of tumors. However, the superiority of different valence states of Cu ions in the antitumor effect is unknown. In this study, we investigated different valence states of Cu ions in modulating tumor cell death by Cu-chelated cyanine dye against triple-negative breast cancer. The cuprous ion (Cu+) and copper ion (Cu2+) were chelated with four nitrogen atoms of dipicolylethylenediamine-modified cyanine for the construction of Cu+ and Cu2+ chelated cyanine dyes (denoted as CC1 and CC2, respectively). Upon 660 nm laser irradiation, the CC1 or CC2 can generate reactive oxygen species, which could disrupt the cyanine structure, achieving the rapid release of Cu ions and initiating the Fenton-like reaction for CDT. Compared with Cu2+-based Fenton-like reagent, the CC1 with Cu+ exhibited a better therapeutic outcome for the tumor due to there being no need for a reduction by glutathione and a shorter route to generate more hydroxyl radicals. Our findings suggest the precision delivery of Cu+ could achieve highly efficient antitumor therapy.

Silicon-containing nanomedicine and biomaterials: materials chemistry, multi-dimensional design, and biomedical application

The invention of silica-based bioactive glass in the late 1960s has sparked significant interest in exploring a wide range of silicon-containing biomaterials from the macroscale to the nanoscale. Over the past few decades, these biomaterials have been extensively explored for their potential in diverse biomedical applications, considering their remarkable bioactivity, excellent biocompatibility, facile surface functionalization, controllable synthesis, etc. However, to expedite the clinical translation and the unexpected utilization of silicon-composed nanomedicine and biomaterials, it is highly desirable to achieve a thorough comprehension of their characteristics and biological effects from an overall perspective. In this review, we provide a comprehensive discussion on the state-of-the-art progress of silicon-composed biomaterials, including their classification, characteristics, fabrication methods, and versatile biomedical applications. Additionally, we highlight the multi-dimensional design of both pure and hybrid silicon-composed nanomedicine and biomaterials and their intrinsic biological effects and interactions with biological systems. Their extensive biomedical applications span from drug delivery and bioimaging to therapeutic interventions and regenerative medicine, showcasing the significance of their rational design and fabrication to meet specific requirements and optimize their theranostic performance. Additionally, we offer insights into the future prospects and potential challenges regarding silicon-composed nanomedicine and biomaterials. By shedding light on these exciting research advances, we aspire to foster further progress in the biomedical field and drive the development of innovative silicon-composed nanomedicine and biomaterials with transformative applications in biomedicine.

Engineered Microbial Nanohybrids for Tumor-Mediated NIR II Photothermal Enhanced Ferroptosis/Cuproptosis and Immunotherapy

The colon tumor microenvironment has a high concentration of H2 S and glutathione, which is highly immunosuppressive and adverse to multiple therapeutic methodologies such as ferroptosis. Here, an engineered microbial nanohybrid based on Escherichia coli (E. coli) and Cu2 O nanoparticles to specific colon tumor therapy and immunosuppression reversion is reported. The as-prepared E. coli@Cu2 O hybrid can accumulate in tumor sites upon intravenous injection, and Cu2 O nanoparticles convert to Cux S by consuming the endogenous H2 S, which exhibits strong photothermal conversion at near-infrared II (NIR II) biological window. Furthermore, E. coli@Cu2 O is able to induce cellular ferroptosis and cuproptosis through inactivation of glutathione peroxidase 4 and aggregation of dihydrolipoamide S-acetyltransferase, respectively. Photothermal-enhanced ferroptosis/cuproptosis achieved by E. coli@Cu2 O reverses the immunosuppression of colon tumors by triggering dendritic cell maturation (about 30%) and T cell activation (about 50% CD8+ T cells). Concerted with immune checkpoint blockade, the engineered microbial nanohybrid can inhibit the growth of abscopal tumors upon NIR illumination. Overall, the designed microbial nanohybrid can achieve tumor-specific photothermal-enhanced ferroptosis/cuproptosis and immunosuppression reversion, showing promise in precise tumor therapy in future clinical translation.

Cancer Cell Membrane-Based Materials for Biomedical Applications

The nanodelivery system provides a novel direction for disease diagnosis and treatment; however, its delivery effectiveness is restricted by the short biological half-life and inadequate tumor targeting. The immune evasion properties and homologous targeting capabilities of natural cell membranes, particularly those of cancer cell membranes (CCM), have gained significant interest. The integration of CCM and nanoparticles has resulted in the emergence of CCM-based nanoplatforms (CCM-NPs), which have gained significant attention due to their unique properties. CCM-NPs not only prolong the blood circulation time of core nanoparticles, but also direct them for homologous tumor targeting. Herein, the history and development of CCM-NPs as well as how these platforms have been used for biomedical applications are discussed. The application of CCM-NPs for cancer therapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CCM-NPs.

A silyl porphyrin derivative conjugated with 6-deoxy-6-sulfo-α-d-glucopyranose functions as an efficient photosensitizer for photodynamic therapy

We synthesized a new silyl porphyrin derivative conjugated with 6-deoxy-6-sulfo-α-d-glucopyranose (SGlc). Conjugation with SGlc improved A549 cellular uptake without significant changes in the photophysical and photochemical properties and subcellular localization. This improved cellular uptake led to enhanced photodynamic activity. Furthermore, conjugation with SGlc suppressed dark toxicity. These advantages were not observed for a conjugate with a glucose molecule. These results indicated that the conjugation with SGlc is a promising strategy for enhancing photodynamic efficacy.

Cu3-xP nanocrystals filled halloysite nanotubes for chemodynamic therapy of breast cancer

Copper-based Fenton-like agents have the ability to convert weakly oxidizing H2O2 into highly oxidizing hydroxyl radicals (·OH) at tumor sites during chemodynamic therapy (CDT). In this study, the interfacial attraction properties between the negatively charged OCP- in sodium phosphathynolate (NaOCP) and the positively charged environment inside the lumen of halloysite nanotubes (HNTs) were utilized to synthesize Cu3-xP nanoparticles in situ within the HNTs. The study investigated the chemical composition, morphology, and structure of Cu3-x P@HNTs. The results indicated uniform distribution of Cu3-xP particles measuring 3-5 nm within HNTs' lumen. Experiments conducted internally and externally to cells confirmed the catalytic capability of Cu3-xP@HNTs to oxidize H2O2 to ·OH. Furthermore, CP@H-CM was synthesized by enclosing Cu3-xP@HNTs in a cancer cell membrane, which selectively targets cancer cells. The experiments revealed the cytotoxicity of CP@H-CM on 4T1 cells. Additionally, the antitumor efficacy of CP@H-CM was evaluated in vivo through tumor recurrence experiments in mice. Moreover, the efficacy of CP@H-CM in repressing tumor growth was enhanced by incorporating infrared laser, indicating a synergistic photodynamic treatment for breast cancer. This study presents an efficacious and viable therapeutic approach to inhibit postoperative tumor reappearance. The implications of this approach are promising, particularly in the domain of tumor treatment and metastasis.

Magnetic Bimetallic Heterointerface Nanomissiles with Enhanced Microwave Absorption for Microwave Thermal/Dynamics Therapy of Breast Cancer

Microwave thermotherapy (MWT) has shown great potential in cancer treatment due to its deep tissue penetration and minimally invasive nature. However, the poor microwave absorption (MA) properties of the microwave thermal sensitizer in the medical frequency band significantly limit the thermal effect of MWT and then weaken the therapeutic efficacy. In this paper, a Ni-based multilayer heterointerface nanomissile of MOFs-Ni-Ru@COFs (MNRC) with improved MA performance in the desired frequency band via introducing magnetic loss and dielectric loss is developed for MWT-based treatment. The loading of the Ni nanoparticle in MNRC mediates the magnetic loss, introducing the MA in the medical frequency band. The heterointerface formed in the MNRC by nanoengineering induces significant interfacial polarization, increasing the dielectric loss and then enhancing the generated MA performance. Moreover, MNRC with the strong MA performance in the desired frequency range not only enhances the MW thermal effect of MWT but also facilitates the electron and energy transfer, generating reactive oxygen species (ROS) at tumor sites to mediate microwave dynamic therapy (MDT). The strategy of strengthening the MA performance of the sensitizer in the medical frequency band to improve MWT-MDT provides a direction for expanding the clinical application of MWT in tumor treatment.

Mn2+/CpG Oligodeoxynucleotides Codecorated Black Phosphorus Nanosheet Platform for Enhanced Antitumor Potency in Multimodal Therapy

Manganese ions (Mn2+)-coordinated nanoparticles have emerged as a promising class of antitumor nanotherapeutics, capable of simultaneously disrupting the immunosuppressive tumor microenvironment (TME) and triggering the stimulator of interferon genes (STING) pathway-dependent antitumor immunity. However, the activation of STING signaling by Mn2+-based monotherapies is suboptimal for comprehensive stimulation of antigen presenting cells and reversal of immunosuppression in the TME. Here, we report the design of a Mn2+/CpG oligodeoxynucleotides (ODNs) codecorated black phosphorus nanosheet (BPNS@Mn2+/CpG) platform based on the Mn2+ modification of BPNS and subsequent adsorption of synthetic CpG ODNs. The coordination of Mn2+ significantly improved the stability of BPNS and the adsorption of CpG ODNs. The acidic TME and endosomal compartments can disrupt the Mn2+ coordination, triggering pH-responsive release of CpG ODNs and Mn2+ to effectively activate the Toll-like receptor 9 and STING pathways. As a result, M2-type macrophages and immature dendritic cells were strongly stimulated in the TME, thereby increasing T lymphocyte infiltration and reversing the immunosuppression within the TME. Phototherapy and chemodynamic therapy, utilizing the BPNS@Mn2+/CpG platform, have demonstrated efficacy in inducing immunogenic cell death upon 808 nm laser irradiation. Importantly, the treatment of BPNS@Mn2+/CpG with laser irradiation exhibited significant therapeutic efficacy against the irradiated primary tumor and effectively suppressed the growth of nonirradiated distant tumor. Moreover, it induced a robust immune memory, providing long-lasting protection against tumor recurrence. This study demonstrated the enhanced antitumor potency of BPNS@Mn2+/CpG in multimodal therapy, and its proof-of-concept application as a metal ion-modified BPNS material for effective DNA/drug delivery and immunotherapy.

Empowering Cartilage Restructuring with Biodegradable Magnesium Doped-Silicon Based-Nanoplatforms: Sustained Delivery and Enhanced Differentiation Potential

Background

Cartilage-related diseases, such as hypoplastic chondrodysplasia a rare genetic disorder that affects newborns, causing abnormal cartilage development and restricted skeletal growth. However, the development of effective treatment strategies for chondrodysplasia still faces significant challenges due to limitations in the controlled drug delivery, biocompatibility, and biodegradability of nanomedicines.

Methods

A biodegradable magnesium doped-silicon based-nanoplatforms based on silicon nanoparticles (MON) was constructed. Briefly, the MON was modified with sulfhydryl groups using MPTMS to form MOS. Further engineering of MOS was achieved by incorporating Mg2+ ions through the "dissolution-regrowth" method, resulting in MMOS. Ica was effectively loaded into the MMOS channels, and HA was anchored on the surface of MOS to obtain MMOS-Ica@HA nanoplatforms. Additionally, in vitro cell experiments and in vivo zebrafish embryo models were used to evaluate the effect of the nanoplatforms on cartilage differentiation or formation and the efficiency of treating chondrodysplasia.

Results

A series of characterization tests including TEM, SEM, DLS, XPS, EDX, and BET analysis validate the successful preparation of MOS-Ica@HA nanoplatforms. The prepared nanoplatforms show excellent dispersion and controllable drug release behavior. The cytotoxicity evaluation reveals the good biocompatibility of MOS-Ica@HA due to the sustained and controllable release of Ica. Importantly, the presence of Ica and Mg component in MOS-Ica@HA significantly promote chondrogenic differentiation of BMSCs via the Smad5/HIF-1α signaling pathway. In vitro and in vivo experiments confirmed that the nanoplatforms improved chondrodysplasia by promoting cartilage differentiation and formation.

Conclusion

The findings suggest the potential application of the developed biodegradable MMOS-Ica@HA nanoplatforms with acceptable drug loading capacity and controlled drug release in chondrodysplasia treatment, which indicates a promising approach for the treatment of chondrodysplasia.

Targeted Delivery of Active Sites by Oxygen Vacancy-Engineered Bimetal Silicate Nanozymes for Intratumoral Aggregation-Potentiated Catalytic Therapy

Biodegradable silicate nanoconstructs have aroused tremendous interest in cancer therapeutics due to their variable framework composition and versatile functions. Nevertheless, low intratumoral retention still limits their practical application. In this study, oxygen vacancy (OV)-enriched bimetallic silicate nanozymes with Fe-Ca dual active sites via modification of oxidized sodium alginate and gallic acid (GA) loading (OFeCaSA-V@GA) were developed for targeted aggregation-potentiated therapy. The band gap of silica markedly decreased from 2.76 to 1.81 eV by codoping of Fe3+ and Ca2+, enabling its excitation by a 650 nm laser to generate reactive oxygen species. The OV that occurred in the hydrothermal synthetic stage of OFeCaSA-V@GA can anchor the metal ions to form an atomic phase, offering a massive fabrication method of single-atom nanozymes. Density functional theory results reveal that the Ca sites can promote the adsorption of H2O2, and Fe sites can accelerate the dissociation of H2O2, thereby realizing a synergetic catalytic effect. More importantly, the targeted delivery of metal ions can induce a morphological transformation at tumor sites, leading to high retention (the highest retention rate is 36.3%) of theranostic components in tumor cells. Thus, this finding may offer an ingenious protocol for designing and engineering highly efficient and long-retention nanodrugs.

Lipid-Centric Design of Plasma Membrane-Mimicking Nanocarriers for Targeted Chemotherapeutic Delivery

The plasma membranes (PM) of mammalian cells contain diverse lipids, proteins, and carbohydrates that are important for systemic recognition and communication in health and disease. Cell membrane coating technology that imparts unique properties of natural plasma membranes to the surface of encapsulated nanoparticles is thus becoming a powerful platform for drug delivery, immunomodulation, and vaccination. However, current coating methods fail to take full advantage of the natural systems because they disrupt the complex and functionally essential features of PMs, most notably the chemical diversity and compositional differences of lipids in two leaflets of the PM. Herein, a new lipid coating approach is reported in which the lipid composition is optimized through a combination of biomimetic and systematic variation approaches for the custom design of nanocarrier systems for precision drug delivery. Nanocarriers coated with the optimized lipids offer unique advantages in terms of bioavailability and efficiency in tumor targeting, tumor penetration, cellular uptake, and drug release. This pilot study provides new insight into the rational design and optimization of nanocarriers for cancer chemotherapeutic drugs and lays the foundation for further customization of cell membrane-mimicking nanocarriers through systematic incorporation of other components.

Embedding Atomically Dispersed Manganese/Gadolinium Dual Sites in Oxygen Vacancy-Enriched Biodegradable Bimetallic Silicate Nanoplatform for Potentiating Catalytic Therapy

Due to their atomically dispersed active centers, single-atom nanozymes (SAzymes) have unparalleled advantages in cancer catalytic therapy. Here, loaded with chlorin e6 (Ce6), a hydrothermally mass-produced bimetallic silicate-based nanoplatforms with atomically dispersed manganese/gadolinium (Mn/Gd) dual sites and oxygen vacancies (OVs) (PMnSA GMSNs-V@Ce6) is constructed for tumor glutathione (GSH)-triggered chemodynamic therapy (CDT) and O2 -alleviated photodynamic therapy. The band gaps of silica are significantly reduced from 2.78 to 1.88 eV by doping with metal ions, which enables it to be excited by a 650 nm laser to produce electron-hole pairs, thereby facilitating the generation of reactive oxygen species. The Gd sites can modulate the local electrons of the atom-catalyzed Mn sites, which contribute to the generation of superoxide and hydroxyl radicals (• OH). Tumor GSH-triggered Mn2+ release can convert endogenous H2 O2 to • OH and realize GSH-depletion-enhanced CDT. Significantly, the hydrothermally generated OVs can not only capture Mn and Gd atoms to form atomic sites but also can elongate and weaken the O-O bonds of H2 O2 , thereby improving the efficacy of Fenton reactions. The degraded Mn2+ /Gd3+ ions can be used as tumor-specific magnetic resonance imaging contrast agents. All the experimental results demonstrate the great potential of PMnSA GMSNs-V@Ce6 as cancer theranostic agent.

Boosting Reactive Oxygen Species Generation with a Dual-Catalytic Nanomedicine for Enhanced Tumor Nanocatalytic Therapy

Generating lethal reactive oxygen species (ROS) within tumors by nanocatalytic medicines is an advanced strategy for tumor-specific therapy in recent years. Nevertheless, the low yield of ROS restrains its therapeutic efficiency. Herein, a dual-catalytic nanomedicine based on tumor microenvironment (TME)-responsive liposomal nanosystem co-delivering CuO2 and dihydroartemisinin (DHA) (LIPSe@CuO2&DHA) is developed to boost ROS generation against tumor. The liposomal nanosystem can degrade in the ROS-overexpressed TME and liberate CuO2 and DHA to initiate Cu-based dual-catalytic ROS generation. Serving as generators of H2O2 and Cu2+, CuO2 can self-produce plenty of toxic hydroxyl radicals via Fenton-like reaction in the acidic TME. Meanwhile, the released Cu2+ can catalyze DHA to generate cytotoxic C-centered radicals. Together, the self-supplied H2O2 and Cu-based dual-catalytic reaction greatly increase the intratumoral level of lethal ROS. Importantly, Cu2+ can decrease the GSH-mediated scavenging effect on the produced ROS via a redox reaction and undergo a Cu2+-to-Cu+ conversion to enhance the Fenton-like reaction, further guaranteeing the high efficiency of ROS generation. Resultantly, LIPSe@CuO2&DHA induces remarkable cancer cell death and tumor growth inhibition, which may present a promising nanocatalytic medicine for cancer therapy.

Multifunctional Nanoparticles for Enhanced Chemodynamic/Photodynamic Therapy through a Photothermal, H2O2-Elevation, and GSH-Consumption Strategy

Chemodynamic therapy (CDT) has witnessed significant advancements in recent years due to its specific properties. Its association with photodynamic therapy (PDT) has also garnered increased attention due to its mutually reinforcing effects. However, achieving further enhancement of the CDT/PDT efficacy remains a major challenge. In this study, we have developed an integrated nanosystem comprising a Fenton catalyst and multifunctional photosensitizers to achieve triply enhanced CDT/PDT through photothermal effects, H2O2 elevation, and GSH consumption. We prepared nano-ZIF-8 vesicles as carriers to encapsulate ferrocene-(phenylboronic acid pinacol ester) conjugates (Fc-BE) and photosensitizers IR825. Subsequently, cinnamaldehyde-modified hyaluronic acid (HA-CA) was coated onto ZIF-8 through metal coordination interactions, resulting in the formation of active targeting nanoparticles (NPs@Fc-BE&IR825). Upon cellular internalization mediated by CD44 receptors, HA-CA elevated H2O2 levels, while released Fc-BE consumed GSH and catalyzed H2O2 to generate highly cytotoxic hydroxyl radicals (·OH). Furthermore, NIR irradiation led to increased ·OH production and the generation of singlet oxygen (1O2), accompanied by a greater GSH consumption. This accelerated and strengthened amplification of oxidative stress can be harnessed to develop highly effective CDT/PDT nanoagents.

Recent progress in the development of nanomaterials targeting multiple cancer metabolic pathways: a review of mechanistic approaches for cancer treatment

Cancer is a very heterogeneous disease, and uncontrolled cell division is the main characteristic of cancer. Cancerous cells need a high nutrition intake to enable aberrant growth and survival. To do so, cancer cells modify metabolic pathways to produce energy and anabolic precursors and preserve redox balance. Due to the importance of metabolic pathways in tumor growth and malignant transformation, metabolic pathways have also been given promising perspectives for cancer treatment, providing more effective treatment strategies, and target-specific with minimum side effects. Metabolism-based therapeutic nanomaterials for targeted cancer treatment are a promising option. Numerous types of nanoparticles (NPs) are employed in the research and analysis of various cancer therapies. The current review focuses on cutting-edge strategies and current cancer therapy methods based on nanomaterials that target various cancer metabolisms. Additionally, it highlighted the primacy of NPs-based cancer therapies over traditional ones, the challenges, and the future potential.

The construction of hierarchical assemblies with in situ generation of chemotherapy drugs to enhance the efficacy of chemodynamic therapy for multi-modal anti-tumor treatments

The effectiveness of chemodynamic therapy (CDT) in cancer treatment is limited by insufficient endogenous H2O2 levels in tumor tissue and an increasing ratio of high valence metal ions. To overcome these challenges, a novel nanotherapeutic approach, named GOx-CuCaP-DSF, has been proposed. This approach involves the design of nanotherapeutics that aim to self-supply H2O2 within cancer cells and provide a supplement of low valence metal ions to enhance the performance of CDT. GOx-CuCaP-DSF nanotherapeutics are engineered by incorporating glucose oxidase (GOx) into Ca2+-doped calcium phosphate (CaP) nanoparticles and loading disulfiram (DSF) through surface adsorption. Under the tumor microenvironment, GOx catalyzes the conversion of tumor-overexpressed glucose (Glu) to liberate H2O2. The degradation of CaP further lowers the pH, facilitating the release of Cu2+ ions and DSF. The rapid reaction between Cu2+ and DSF leads to the generation of Cu+, increasing the Cu+/Cu2+ ratio and promoting the Cu+-based Fenton reaction, which enhances the efficiency of CDT. Simultaneously, DSF undergoes conversion to diethyldithiocarbamate acid (ET), forming a copper(II) complex (Cu(II)ET) by strong chelation with Cu ions. This Cu(II)ET complex, a potent chemotherapeutic drug, exhibits a synergistic therapeutic effect in combination with CDT. Moreover, the elevated Cu+ species resulting from DSF reaction promotes the aggregation of toxic mitochondrial proteins, leading to cell cuproptosis. Overall, the strategy of integrating the chemodynamic therapy efficiency of the Fenton reaction with the activation of efficacious cuproptosis using a chemotherapeutic drug presents a promising avenue for enhancing the effectiveness of multi-modal anti-tumor treatments.

NIR Light-Activated and RGD-Conjugated Ultrasmall Fe/PPy Nanopolymers for Enhanced Tumor Photothermal Ferrotherapy and MR Imaging

Iron-based nanomaterials have shown great promise for tumor ferrotherapy in recent years. However, nanoparticle-induced ferroptosis has low therapeutic efficacy owing to unsatisfactory Fenton reaction activity in a typical tumor microenvironment. In this study, NIR light-activated Fe/PPy-RGD nanopolymers were developed to combine photothermal therapy and ferrotherapy and achieve enhanced antitumor activity. Importantly, Fe/PPy-RGD exhibited excellent therapeutic performance under NIR light activation both in vitro and in vivo. Under irradiation with NIR light, the heat generated by Fe/PPy-RGD not only induced a therapeutic photothermal effect but also enhanced the release of iron ions and the Fenton reaction by inducing ferroptosis. Additionally, by virtue of RGD conjugation and its ultrasmall size, Fe/PPy-RGD could effectively accumulate at tumor sites in living mice after systemic administration and could be monitored via MR imaging. Hence, this study provides a promising approach for integrating ferrotherapy with photothermal therapy to achieve enhanced tumor treatment.

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.

Hierarchical MOF@AuNP/Hairpin Nanotheranostic for Enhanced Photodynamic Therapy via O2 Self-Supply and Cancer-Related MicroRNA Imaging In Vivo

Developing a nanotheranostic with a high sensing performance and efficient therapy was significant in cancer diagnosis and treatment. Herein, a Au nanoparticle and hairpin-loaded photosensitive metal-organic framework (PMOF@AuNP/hairpin) nanotheranostic was constructed by growing AuNPs on PMOF in situ and then attaching hairpins. On the one hand, the PMOF@AuNP/hairpin nanotheranostic could effectively transfer O2 into ROS, facilitating efficient PDT. Additionally, the nanotheranostic possessed catalase-like activity, which could effectively catalyze H2O2 to generate O2, thus achieving O2-evolving PDT and significantly enhancing the antitumor effect of PDT in vivo. On the other hand, the nanotheranostic showed a high loading efficiency of hairpins and achieved the sensitive and selective detection of miR-21 both in living cells and in vivo. Moreover, the nanotheranostic could dynamically monitor the miR-21 level. Due to the excellent imaging performance, the nanotheranostic could recognize cancer cells and might provide important information on cancer progression for PDT. The developed PMOF@AuNP/hairpin nanotheranostic provided a useful tool for tumor diagnosis and antitumor therapy.

Metal-Organic Framework for Hypoxia/ROS/pH Triple-Responsive Cargo Release

Nanoparticulate antitumor photodynamic therapy (PDT) is suffering from a very short lifetime, limited diffusion distance of reactive oxygen species (ROS). Herein, a hypoxia/ROS/pH triple-responsive metal-organic framework (MOF) is designed to facilitate the on-demand release of photosensitizers and hence enhanced PDT efficacy. Tailored azo-containing imidazole ligand is coordinated with zinc to form MOF where photosensitizer (Chlorin e6/Ce6) is encapsulated. Azo can be reduced by overexpressed azoreductase in hypoxic tumor cells, resulting in depletion of glutathione (GSH) and thioredoxin (Trx) which are major antioxidants against ROS oxidative damage in PDT, resulting in rapid cargo release and additional efficacy amplification. The imidazole ionization causes a proton sponge effect to ensure the disintegration of the nanocarriers in acidic organelles, allowing the rapid release of Ce6 through lysosome escape. Under light irradiation, ROS produced by Ce6 may oxidize imidazole to urea, resulting in rapid cargo release. All of the triggers are expected to show interactive synergism. The pH- and hypoxia-responsiveness can improve the release rate of Ce6 for enhanced PDT therapy, whereas the consumption of oxygen by PDT may induce elevated hypoxia and hence in turn enhanced cargo release. This work highlights the role of triple-responsive nanocarriers for triggered photosensitizer release and improved antitumor PDT efficacy.

Logic gate controlled theranostic nanoagents for in situ microwave thermal therapeutic efficacy evaluation

In vivo monitoring of treatment response is of great significance for tumor therapy in clinical trials, but it remains a formidable challenge. Herein, we demonstrate a logic AND gate theranostic nanoagent that responds to the coexistence of endogenous and exogenous stimuli, namely HAuCl4@1-Tetradecanol@Gd-based metal-organic framework@SiO2 nanocomposites (APGS NCs). Upon microwave (MW) irradiation, HAuCl4 in the inner part of APGS NCs reacts with the tumor-associated glutathione (GSH). Subsequently, it transforms into an active luminescent form of Au@1-Tetradecanol@Gd-MOF@SiO2 nanocomposites (AuPGS NCs). The intensity of generated fluorescence is correlated with the tumor thermal-injury status. Thus, the generation of AuPGS NCs with high intensity fluorescence under the co-activation of MW and GSH can visualize the treatment effects during MW thermal therapy and instantly modulate the irradiation time and range for optimal outcomes. Hence, this logic gate controlled APGS NCs makes MW thermal therapy eliminate tumor cells completely. This research offers an effective strategy for the design and preparation of activatable theranostic nanoagents for precise tumor imaging and therapy.

A metal ions-mediated natural small molecules carrier-free injectable hydrogel achieving laser-mediated photo-Fenton-like anticancer therapy by synergy apoptosis/cuproptosis/anti-inflammation

Tumor microenvironment (TME) plays an important role in the tumorigenesis, proliferation, invasion and metastasis. Thereby developing synergistic anticancer strategies with multiple mechanisms are urgent. Copper is widely used in the treatment of tumor chemodynamic therapy (CDT) due to its excellent laser-mediated photo-Fenton-like reaction. Additionally, copper can induce cell death through cuproptosis, which is a new modality different from the known death mechanisms and has great promise in tumor treatment. Herein, we report a natural small molecules carrier-free injectable hydrogel (NCTD Gel) consisted of Cu²⁺-mediated self-assembled glycyrrhizic acid (GA) and norcantharidin (NCTD), which are mainly governed by coordination and hydrogen bonds. Under 808 nm laser irradiation, NCTD Gel can produce reactive oxygen species (ROS), consume glutathione (GSH) and overcome hypoxia in TME, leading to synergistically regulate TME via apoptosis, cuproptosis and anti-inflammation. In addition, NCTD Gel's CDT display high selectivity and good biocompatibility as it relies on the weak acidity and H₂O₂ overexpression of TME. Notably, NCTD Gel's components are originated from clinical agents and its preparation process is easy, green and economical, without any excipients. This study provides a new carrier-free hydrogel synergistic antitumor strategy, which has a good prospect in industrial production and clinical transformation.

Manganese-Based Nanotheranostics for Magnetic Resonance Imaging-Mediated Precise Cancer Management

Manganese (Mn)-based magnetic resonance imaging (MRI) has become a competitive imaging modality for cancer diagnosis due to its advantages of non-invasiveness, high resolution and excellent biocompatibility. In recent years, a variety of Mn contrast agents based on different material systems have been synthesized, and a series of multi-purpose Mn nanocomposites have also emerged, showing satisfactory relaxation efficiency and MRI performance thus possess the transformation and application value in MRI-synergized cancer diagnosis and treatment. This tutorial review starts from the classification and properties of Mn-based nanomaterials, and then summarizes various preparation and functionalization strategies of nanosized Mn contrast agents, especially focuses on the latest progress of Mn contrast agents in MRI-synergized precise cancer theranostics. In addition, present review also discusses the current clinical transformation obstacles such as unclear molecular mechanisms, potential nanotoxicity, and scale production constraints. This paper provides evidence-based recommendations about the future prospects of multifunctional nanoplatforms, as well as technical guidance and panoramic expectations for the design of clinically meaningful cancer management programs.

B, P, and S heteroatom doped, bio- and hemo-compatible 2D graphitic-carbon nitride (g-C3N4) with antioxidant, light-induced antibacterial, and bioimaging endeavors

The synthesis of two-dimensional (2D) graphiticg-C3N4and heteroatom-doped graphitic H@g-C3N4(H: B, P, or S) particles were successfully done using melamine as source compounds and boric acid, phosphorous red, and sulfur as doping agents. The band gap values of 2Dg-C3N4, B50@g-C3N4, P50@g-C3N4, and S50@g-C3N4structures were determined as 2.90, 3.03, 2.89, and 2.93 eV, respectively. The fluorescent emission wavelengths of 2Dg-C3N4, B50@g-C3N4, P50@g-C3N4, and S50@g-C3N4structures were observed at 442, 430, 441, and 442 nm, respectively upon excitation atλEx= 325 nm. There is also one additional new emission wavelength was found at 345 nm for B50@g-C3N4structure. The blood compatibility test results ofg-C3N4, B50@g-C3N4, P50@g-C3N4, and S50@g-C3N4structures revealed that all materials are blood compatible with <2% hemolysis and >90% blood clotting indices at 100μg ml-1concentration. The cell toxicity of the prepared 2D graphitic structures were also tested on L929 fibroblast cells, and even the heteroatom doped hasg-C3N4structures induce no cytotoxicity was observed with >91% cell viability even at 250μg ml-1particle concentration with the exception of P50@g-C3N4which as >75 viability. Moreover, for 2Dg-C3N4, B50@g-C3N4, and S50@g-C3N4constructs, even at 500μg ml-1concentration, >90% cell viabilities was monitored. As a diagnostic material, B50@g-C3N4was found to have significantly high penetration and distribution abilities into L929 fibroblast cells granting a great potential in fluorescence imaging and bioimaging applications. Furthermore, the elemental doping with B, P, and S ofg-C3N4were found to significantly increase the photodynamic antibacterial activity e.g. more than half of bacterial elimination by heteroatom-doped forms ofg-C3N4under UVA treatment was achieved.

Targeting ferroptosis opens new avenues for the development of novel therapeutics

Ferroptosis is an iron-dependent form of regulated cell death with distinct characteristics, including altered iron homeostasis, reduced defense against oxidative stress, and abnormal lipid peroxidation. Recent studies have provided compelling evidence supporting the notion that ferroptosis plays a key pathogenic role in many diseases such as various cancer types, neurodegenerative disease, diseases involving tissue and/or organ injury, and inflammatory and infectious diseases. Although the precise regulatory networks that underlie ferroptosis are largely unknown, particularly with respect to the initiation and progression of various diseases, ferroptosis is recognized as a bona fide target for the further development of treatment and prevention strategies. Over the past decade, considerable progress has been made in developing pharmacological agonists and antagonists for the treatment of these ferroptosis-related conditions. Here, we provide a detailed overview of our current knowledge regarding ferroptosis, its pathological roles, and its regulation during disease progression. Focusing on the use of chemical tools that target ferroptosis in preclinical studies, we also summarize recent advances in targeting ferroptosis across the growing spectrum of ferroptosis-associated pathogenic conditions. Finally, we discuss new challenges and opportunities for targeting ferroptosis as a potential strategy for treating ferroptosis-related diseases.

A Cu@ZIF-8 encapsulated antibacterial and angiogenic microneedle array for promoting wound healing

Skin wounds caused by external injuries remain a serious challenge in clinical practice. Wound dressings that are antibacterial, pro-angiogenic, and have potent regeneration capacities are highly desirable for wound healing. In this study, a minimally invasive and wound-friendly Cu@ZIF-8 encapsulated PEGDA/CMCS microneedle (MN) array was fabricated using the molding method to promote wound healing. The MNs had good biocompatibility, excellent mechanical strength, as well as strong antibacterial properties and pro-angiogenic effects. When incubated with H2O2, Cu@ZIF-8 nanoparticles generated reactive oxygen species, which contributed to their antibacterial properties. Due to the oxidative stress of the cupric ions released from Cu@ZIF-8 and the anti-bacterial capability of the PEGDA/CMCS hydrogel scaffold, such an MN array presents excellent antibacterial activity. Moreover, with the continuous release of Cu ions from the scaffold, such MNs are effective in terms of promoting angiogenesis. With considerable biocompatibility and a minimally invasive approach, the degradable MN array composed of PEGDA/CMCS possessed superior capabilities to continuously and steadily release the loaded ingredients and avoid secondary damage to the wound. Benefiting from these features, the Cu@ZIF-8 encapsulated degradable MN array can dramatically accelerate epithelial regeneration and neovascularization. These results indicated that the combination of Cu@ZIF-8 and degradable MN arrays is valuable in promoting wound healing, which opened a new window for treatment of skin defection.