Three-Step Depletion Strategy of Glutathione: Tunable Metal-Organic-Framework-Engineered Nanozymes for Driving Oxidative/Nitrative Stress to Maximize Ferroptosis Therapy

Hybrid membrane based biomimetic nanodrug with high-efficient melanoma-homing and NIR-II laser-amplified peroxynitrite boost properties for enhancing antitumor therapy via effective immunoactivation

Owing to the excellent stability, anticancer activity and immunogenicity, peroxynitrite (ONOO-) has been gained enormous interests in cancer therapy. Nevertheless, precise delivery and control release of ONOO- in tumors remains a big challenge. Herein, B16F10 cancer cell membrane/liposome hybrid membrane (CM-Lip) based biomimetic nanodrug with high-efficient tumor-homing and NIR-II laser controlled ONOO- boost properties was designed for melanoma treatment. Briefly, NIR-II molecule IR1061, NO donor BNN6 and β-lapachone (Lapa) were firstly encapsulated in the heat-responsive palmitoyl phosphatidylcholine/cholesterol liposome, followed by fusion with B16F10 cell membrane (CM) to obtain biomimetic CM-Lip@(IR/BNN6/Lapa). The hybrid membrane-based nanodrug displayed excellent biocompatibility and melanoma-targeting efficiency. Upon 1064 nm laser irradiation, the mild photothermal effect of CM-Lip@(IR/BNN6/Lapa) firstly triggered the release of NO and Lapa, which subsequently catalyzed the quinone oxidoreductase 1 (NQO1) overexpressed in tumors to produce O2•-, finally caused intraturmal ONOO- boost via cascade reaction. The boosted ONOO- could effectively inhibit melanoma by ways of triggering mitochondrion-mediated apoptotic pathway, upregulating 3-nitrotyrosine expression, inducing DNA damage and inhibiting DNA repair enzyme expression of poly (ADP-ribose) polymerase 1 (PARP-1). Moreover, ONOO- displayed excellent immunoactivation and immunomodulation activities by effectively inducing immunogenic tumor cell death, promoting dendritic cells maturation, increasing cytotoxic T lymphocytes expression and repolarizing M1-phenotype macrophages.

Twin-Tail Tadpole-Shaped Ce6-Peptide Conjugate for Enhanced Photodynamic Cancer Therapy

Despite its therapeutic potential, photodynamic therapy faces several key limitations in clinical applications, including poor drug delivery and insufficient tumor selectivity. We engineered RFYFYR-Ce6-RFYFYR (R-Ce6-R), a twin-tail peptide-photosensitizer conjugate that self-assembles into nanostructures for improved cancer treatment. By incorporating arginine-rich peptide sequences, this design not only enhances cellular internalization but also promotes peroxynitrite (ONOO-) formation, amplifying the therapeutic effect. Our studies revealed that R-Ce6-R achieves 33-fold higher potency than unmodified Ce6, with an IC50 of 0.18 μM. The conjugate demonstrated selective accumulation in tumor tissue, robust ROS generation, and complete tumor regression in animal models while maintaining a favorable safety profile. These results establish R-Ce6-R as an innovative approach for advancing photodynamic therapy in cancer treatment.

Synergistic Co-Cu Dual-Atom Nanozyme with Promoted Catalase-like Activity for Parkinson's Disease Treatment

Neurodegenerative diseases like Parkinson's disease (PD) are intimately associated with oxidative stress due to the excessive highly reactive oxygen species (ROS), leading to the damage of dopaminergic neurons. Herein, we develop a Co-Cu dual-atom nanozyme (CoCu-DAzyme) by uniformly anchoring Co and Cu active sites onto an AlO(OH) substrate that exhibits remarkable catalase-like catalytic activity, far exceeding that of the Co or Cu single-atom counterparts. The following density functional theory calculations reveal that the Co sites efficiently enable H2O2 adsorption, while Cu sites promote charge transfer, synergistically promoting the catalytic decomposition of H2O2 into H2O and O2. Encouragingly, the developed CoCu-DAzyme notably ameliorates α-synuclein aggregation and alleviates the motor dysfunction inCaenorhabditis elegansPD models by substantively scavenging in vivo ROS. This research shows a novel therapeutic strategy for oxidative-stress-related neurodegenerative disorders by developing well-engineered nanozymes.

Tumor microenvironment-responsive and modulatory manganese-based nanoenzyme for enhanced tumor immunotherapy

The characteristics of the tumor microenvironment (TME) have a close and internal correlation with the effect of cancer immunotherapy, significantly affecting the progression and metastasis of cancer. The rational design of nanoenzymes that possess the ability to respond to and regulate the TME is driving a new direction in catalytic immunotherapy. In this study, we designed a multifunctional manganese (Mn)-based nanoenzyme that is responsive to acidic pH and overxpressed H2O2 at tumor site and holds capability of modulating hypoxic and immunosuppressive TME for synergistic anti-tumor photothermal/photodynamic/immunotherapy. We found that this artificial nanoenzyme promoted peroxidase-like and catalase-like activities and catalyzed the in-situ decomposition of H2O2, a metabolic waste product in the TME, into ∙OH and O2, resulting in a ROS burst for killing tumors and relieving hypoxic TME to enhance cancer therapy. Besides the photothermal effect and the enhancement of ROS burst-induced immunogenic cell death, combination of Mn2+ released from Mn-based nanoenzyme in acidic TME and programmed death-ligand 1 blockade triggered a significant anti-tumor immune response. A remarkable in vivo synergistic therapeutic effect was achieved with effective inhibition of primary tumor growth and lung metastasis. Therefore, this TME-responsive Mn-based nanoenzyme offers a safe and efficient platform for reversing the immunosuppressive microenvironment and achieving synergistic anti-tumor immunotherapy.

Induced Ferroptosis Pathway by Regulating Cellular Lipid Peroxidation With Peroxynitrite Generator for Reversing "Cold" Tumors

Overcoming the resistance of tumor cells to apoptosis and immunosuppression is an important challenge to improve tumor immunotherapy. Non-apoptotic death mode of ferroptosis has been regarded as a new strategy to enhance tumor immunotherapy against drug-resistant cancers. The lethal accumulation of lipid peroxides (LPO) determines the progress of ferroptosis. The high susceptibleness of ferroptosis provides an opportunity for combating triple-negative breast cancer. Reactive nitrogen species (RNS) produced by nitric oxide (NO) and reactive oxygen species (ROS) is more lethal than ROS for tumor cells. Herein, an RNS-mediated immunotherapy strategy for inducing ferroptosis pathway is proposed by improving LPO accumulation, and constructed a multifunctional liposome (Lipo-MT-SNAP) comprised of peroxynitrite (ONOO-) generator, tumor targeted group, inhibiting glutathione peroxidase 4 (GPX4), and basic units (dipalmitoyl phosphatidylcholine and cholesterol). The significant enhancement of LPO resulted from the intense oxidative damage of ONOO- impaired synthesis of GPX4 by depleting glutathione, which further amplified ferroptosis and triggered immunogenic cell death. In vivo, RNS-mediated photoimmunotherapy can promote polarization of M2 to M1 macrophages and dendritic cells maturation, further infiltrate T cells, regulate the secretion of inflammatory factors, and reprogram the tumor microenvironment. The powerful RNS-mediated ferroptosis induces strong immunogenicity and effectively inhibit tumor proliferation.

A strategy of "adding fuel to the flames" enables a self-accelerating cycle of ferroptosis-cuproptosis for potent antitumor therapy

Cuproptosis in antitumor therapy faces challenges from copper homeostasis efflux mechanisms and high glutathione (GSH) levels in tumor cells, hindering copper accumulation and treatment efficacy. Herein, we propose a strategy of "adding fuel to the flames" for potent antitumor therapy through a self-accelerating cycle of ferroptosis-cuproptosis. Disulfiram (DSF) loaded hollow mesoporous copper-iron sulfide (HMCIS) nanoparticle with conjugation of polyethylene glycol (PEG) and folic acid (FA) (i.e., DSF@HMCIS-PEG-FA) was developed to swiftly release DSF, H2S, Cu2+, and Fe2+ in the acidic tumor microenvironment (TME). The hydrogen peroxide (H2O2) levels and acidity within tumor cells enhanced by the released H2S induce acceleration of Fenton (Fe2+) and Fenton-like (Cu2+) reactions, enabling the powerful tumor ferroptosis efficacy. The released DSF acts as a role of "fuel", intensifying catalytic effect ("flame") in tumor cells through the sustainable Fenton chemistry (i.e., "add fuel to the flames"). Robust ferroptosis in tumor cells is characterized by serious mitochondrial damage and GSH depletion, leading to excess intracellular copper that triggers cuproptosis. Cuproptosis disrupts mitochondria, compromises iron-sulfur (Fe-S) proteins, and elevates intracellular oxidative stress by releasing free Fe3+. These interconnected processes form a self-accelerating cycle of ferroptosis-cuproptosis with potent antitumor capabilities, as validated in both cancer cells and tumor-bearing mice.

Unprecedented Organogermanium Functionalized GeIV-SbIII-Templating Polyoxotungstate Nanocluster for Photothermal-Chemodynamic Cancer Therapy

The function-oriented synthesis of polyoxometalate (POM) nanoclusters has become an increasingly important area of research. Herein, the well-known broad-spectrum anticancer drug Ge-132 which contains GeIV as potential heteroatoms and carboxyl coordination sites, is introduced to the POM system, leading to the first organogermanium functionalized GeIV-SbIII-templating POM nanocluster Na4[H2N(CH3)2]16 H18[Sm4(H2O)12W4O14Ge(CH2CH2COOH)]2[SbW9O33]4[Ge(CH2CH2COOH) SbW15O54]2·62H2O (1). An unprecedented organogermanium templating Dawson-like [Ge(CH2CH2COOH)SbW15O54]12- building block is discovered. To take advantage of the potential pharmaceutical activity of such an organogermanium-functionalized POM cluster, 1 is further composited with gold nanoparticles (NPs) to prepare 1-Au NPs, which doubles the blood circulation time of 1-based nanodrug. Efficient separation of photogenerated charges in 1-Au NPs largely boosts the photothermal conversion efficiency (PCE = 55.0%), which is nearly 2.1 times that of either single 1 (PCE = 26.7%) or Au NPs (PCE = 26.2%), and simultaneously facilitate the generation of toxic activate reactive oxygen species in tumor microenvironment. Based on these findings, it is demonstrated that 1-Au NPs are a multifunctional and renal clearable nanomedicine with great potential in photoacoustic imaging guiding photothermal-chemodynamic therapy for breast cancer.

Gelatin-coated glutathione depletion and oxygen generators in potentiated chemotherapy for pancreatic cancer

Chemotherapy is generally acknowledged as an effective method for pancreatic cancer (PC). However, its treatment efficacy is often compromised due to inefficient drug delivery and drug resistance propensity of tumor tissues. The purpose of this study is to design and develop a novel drug delivery system (Manganese-doped mesoporous silica nanoparticles, Mn-MSN) in which paclitaxel (PTX), a conventional chemotherapeutic agent used to effectively treat pancreatic cancer clinically. Through cross-linking with glutaraldehyde, gelatin (Ge) was encapsulated on the carrier surface, endowing the nanoparticles (Ge-Mn-MSN@PTX) with excellent biocompatibility, low hemolytic activity, and enzyme-responsive degradation. Mn was added for the following purposes: (1) catalyzing hydrogen peroxide (H2O2) to generate oxygen (O2), thereby alleviating tumor hypoxia and drug resistance; (2) depleting glutathione (GSH), inducing intracellular lipid peroxidation and ferroptosis; (3) enabling real-time monitoring of the therapeutic efficacy of the nanoparticles via magnetic resonance imaging (MRI). The experimental results demonstrated that Ge-Mn-MSN@PTX has satisfactory biosafety, antitumor activity, controlled drug release as well as imaging tracking capabilities. In the SW1990 nude mice model, the Ge-Mn-MSN@PTX effectively inhibited tumor growth by suppressing the expression of the resistance protein P-glycoprotein (P-gp) and inducing ferroptosis. In conclusion, the designed gelatin-coated Mn-MSN shows potential for application in future pancreatic cancer therapy.

Metal ions-anchored bacterial outer membrane vesicles for enhanced ferroptosis induction and immune stimulation in targeted antitumor therapy

The activation of ferroptosis presents a versatile strategy for enhancing the antitumor immune responses in cancer therapy. However, developing ferroptosis inducers that combine high biocompatibility and therapeutic efficiency remains challenging. In this study, we propose a novel approach using biological nanoparticles derived from outer membrane vesicles (OMVs) of Escherichia coli for tumor treatment, aiming to activate ferroptosis and stimulate the immune responses. Specifically, we functionalize the OMVs by anchoring them with ferrous ions via electrostatic interactions and loading them with the STING agonist-4, followed by tumor-targeting DSPE-PEG-FA decoration, henceforth referred to as OMV/SaFeFA. The anchoring of ferrous ions endows the OMVs with peroxidase-like activity, capable of inducing cellular lipid peroxidation by catalyzing H2O2 to •OH. Furthermore, OMV/SaFeFA exhibits pH-responsive release of ferrous ions and the agonist, along with tumor-targeting capabilities, enabling tumor-specific therapy while minimizing side effects. Notably, the concurrent activation of the STING pathway and ferroptosis elicits robust antitumor responses in colon tumor-bearing mouse models, leading to exceptional therapeutic efficacy and prolonged survival. Importantly, no acute toxicity was observed in mice receiving OMV/SaFeFA treatments, underscoring its potential for future tumor therapy and clinical translation.

Sono-blasting Triggered Cascading-Amplification of Oxidative Stress for Enhanced Interventional Therapy of Hepatocellular Carcinoma

Interventional therapy is widely regarded as a highly promising treatment approach for nonsurgical liver cancer. However, the development of drug resistance and tolerance to hypoxic environments after embolization can lead to increased angiogenesis, enhanced tumor cell stemness, and greater invasiveness, resulting in metastasis and recurrence. To address these challenges, a novel approach involving the use of lecithin and DSPE-PEG comodified Ca2+ loaded (NH4)2S2O8 (LDCNSO) drug in combination with transcatheter arterial embolization (TAE) has been proposed. The sono-blasting effect of LDCNSO under ultrasound triggers a cascading amplification of oxidative stress, by releasing sulfate radical (·SO4-), hydroxyl radical (·OH), and superoxide (·O2-), inducing Ca2+ overload, and reducing glutathione (GSH) levels, which eventually leads to apoptosis. LDCNSO alongside TAE has demonstrated remarkable therapeutic efficacy in the rabbit orthotopic cancer model, resulting in significant inhibition of tumor growth. This research provides valuable insights for the effective treatment of orthotopic tumors.

Wireless Powered Microwave-Light Conversion Platform with Dual-Stimulus Nanoresponder Coating for Deep-Seated Photodynamic Therapy

Traditional external field-assisted therapies, e.g., microwave (MW) therapy and phototherapy, cannot effectively and minimally damage eliminate deep-seated infection, owing to the poor penetrability of light and low reactive oxygen species (ROS) stimulation capability of MW. Herein, an implantable and wireless-powered therapeutic platform (CNT-FeTHQ-TS), in which external MW can be converted into internal light via MW wireless-powered light-emitting chips, is designed to eradicate deep-seated tissue infections by MW-induced deep-seated photodynamic therapy. In application, CNT-FeTHQ-TS is implanted at internal lesions, and the chip emits light under external MW irradiation. Subsequently, CNT-FeTHQ coating in the platform can respond to both MW and light simultaneously to generate ROS and MW-hyperthermia for rapid and precise sterilization at focus. Importantly, MW also improves the photodynamic performance of CNT-FeTHQ by introducing vacancies in FeTHQ to facilitate the photoexcitation process and changing the spin state of electrons to inhibit the complexation of photogenerated electron-hole pairs, which were confirmed by simulation calculations and in situ MW-irradiated photoluminescence experiments. In vivo, CNT-FeTHQ-TS can effectively cure mice with Staphylococcus aureus infection in dorsal subcutaneous tissue. This work overcomes the key clinical limitations of safe energy transmission and conversion for treating deep-seated infections.

Erythrocyte-Like Mesoporous PDA@CeO2 Nanozyme with Dual Drugs for Periodontitis Treatment

Periodontitis is a chronic oral inflammatory disease with the characteristic of excess oxidative stress in the inflammatory site, dramatically decreasing the quality of life. Studies show that nanozymes can be ideal candidates for ROS scavenging in periodontitis. Here, we design a multipath anti-inflammatory mesoporous polydopamine@cerium oxide nanobowl (mPDA@CeO2 NB) with multienzyme mimicking properties, which combines the advantages of both CeO2 NP and mPDA NB for synergistically eliminating reactive oxygen species (ROS), including hydroxyl radical (•OH), hydrogen peroxide (H2O2), and superoxide (O2•-). Besides, the erythrocyte-like structure of mNBs makes them a facility for cell uptake, and the mesopores can load both hydrophobic and hydrophilic drugs for combined anti-inflammatory therapy. In vitro and in vivo experiments prove that the combination of CeO2 and mPDA can synergistically achieve multiple complementary ROS eliminations and suppression of ROS-induced inflammation. Moreover, the ROS regulation plus anti-inflammatory drugs in one mPDA@CeO2 NB prevents the progression of periodontitis in a mouse model. Therefore, the design of mPDA@CeO2 NB with these excellent properties provides a therapeutic strategy for inflammatory diseases.