A Mild Hyperthermia Hollow Carbon Nanozyme as Pyroptosis Inducer for Boosted Antitumor Immunity

Photothermal amplified multizyme activity for synergistic photothermal-catalytic tumor therapy

Nano-enzymatic catalytic therapy has been widely explored as a promising tumor therapeutic method with specific responsiveness to the tumor microenvironment (TME). However, the inherent lower and simplex catalytic efficiency impairs their anti-tumor efficacy. Therefore, developing novel nanozymes with relatively high and multiple catalytic characteristics, simultaneously enhancing the enzyme-like activity of nanozymes using the proper method, photothermal promoted catalytic property, is a reliable way. In this paper, we report a manganese oxide/nitrogen-doped carbon composite nanoparticles (MnO-N/C NPs) with multi-enzyme mimetic activity and photothermal conversional effect. The peroxidase (POD)-like/oxidase (OXD)-like/catalase (CAT)-like activity of MnO-N/C nanozymes was accelerated upon exposure to an 808 nm NIR laser. In vitro and in vivo results proved that the MnO-N/C NPs shown excellent magnetic resonance imaging (MRI) guided synergistic photothermal-enhanced catalytic treatment and photothermal therapy of liver cancer. The photothermal enhanced multi-enzyme activity maximizes the efficacy of catalytic and photothermal therapy while reducing harm to healthy cells, thereby offering valuable insights for the development of next-generation photothermal nanozymes to enhance tumor therapy.

Copper-Based Bio-Coordination Nanoparticle for Enhanced Pyroptosis-Cuproptosis Cancer Immunotherapy through Redox Modulation and Glycolysis Inhibition

Copper-based nanoparticles have garnered significant interest in cancer therapy due to their ability to induce oxidative stress and cuproptosis in cancer cells. However, their antitumor effectiveness is constrained by the dynamic redox balance and the metabolic shift between oxidative phosphorylation and glycolysis. Here, a polydopamine-coated copper-α-ketoglutaric acid (α-KG) coordination polymer nanoparticle (CKPP) is designed for combined pyroptosis-cuproptosis cancer immunotherapy by amplifying reactive oxygen species (ROS) production and regulating cellular metabolism. The intracellular redox imbalance is achieved through the synergistic effects of α-KG-induced mitochondrial metabolic reprogramming, photothermally enhanced superoxide dismutase-like activity of polydopamine, and glutathione depletion by copper ions. The multifaceted redox modulation results in a substantial increase in intracellular ROS levels, triggering oxidative stress and subsequent pyroptosis in cancer cells. Furthermore, α-KG shifts cellular metabolism from glycolysis to oxidative phosphorylation, thereby enhancing cuproptosis induced by copper ions. The combination of ROS dyshomeostasis and glycolysis inhibition results in a potent enhancement of pyroptosis-cuproptosis-mediated cancer therapy. In a murine model of colorectal cancer, CKPP exhibited a remarkable anticancer effect, achieving a tumor inhibition rate of 96.3% and complete tumor eradication in two out of five cases. Overall, this bio-engineered metal-organic nanocomposite demonstrates significant potential for treating cancer through combined pyroptosis-cuproptosis cancer immunotherapy.

Oxidative stress-augmented Cu-doped hollow mesoporous carbon nanozyme for photothermal/photodynamic synergistic therapy

Photodynamic therapy (PDT) has witnessed remarkable progress in recent years owing to its specific properties. Given that the antioxidation system of tumor microenvironment (TME) adversely affects treatment outcomes, powerful TME modulators can significantly resolve the limitation of PDT. Herein, we developed a PEG-modified Cu2+-doped hollow mesoporous carbon nanozyme (CHC-PEG) and loaded insoluble photosensitizer IR780 into its pores and cavities to construct the multifunctional nano-system IR780/CHCP. CHC-PEG nanozyme could perform photothermal therapy (PTT) effect and protect IR780 from aggregation-caused quenching (ACQ) effect, while exerting peroxidase (POD)-mimetic activity and the ability of consuming glutathione (GSH) to achieve oxidative stress-augmented PDT effect. When exposed to near-infrared (NIR) light, IR780 was stimulated to produce singlet oxygen (1O2) and CHC-PEG could increase the temperature of TME to exert stronger POD-mimetic activity for producing more hydroxyl radicals (OH), therefore the IR780/CHCP nano-system exhibited remarkable tumor growth inhibition. Benefited by the enhanced synergistic effect, IR780/CHCP exhibited remarkable in vivo tumor growth inhibition, with the tumor inhibition rate of 93 %, and had no significant effect on major organs. Above all, IR780/CHCP could resist the antioxidant system in TME to enhance the level of oxidative stress, thereby enabling effective anti-tumor therapy. This study introduced a novel strategy to effectively promote the synergistic PTT/PDT effect by the enhanced oxidative stress.

Controllable All-in-One Biomimetic Hollow Nanoscaffold Initiating Pyroptosis-Mediated Antiosteosarcoma Targeted Therapy and Bone Defect Repair

Pyroptosis has gained attention for its potential to reinvigorate the immune system within the tumor microenvironment. However, current approaches employing pyroptosis inducers suffer from limitations. They primarily rely on single agents, lack precise targeting, and potentially disrupt the intricate bone formation microenvironment, hindering local repair of tumor-induced bone defects. Therefore, a therapeutic strategy is urgently needed that can effectively trigger pyroptosis while simultaneously promoting bone regeneration. This research introduces an all-in-one construct designed to address these limitations. It combines a cell-camouflaged shell with an autosynergistic reactive oxygen species (ROS) generating polymer. This construct incorporates a hollow core of manganese dioxide (HMnO2) embedded with the photosensitizer IR780 and disguised by the cell membrane of an M1 macrophage. The M1 macrophage membrane grants the construct stealth-like properties, enabling it to accumulate selectively at the tumor site. Upon laser irradiation, IR780 acts as an exogenous trigger for ROS generation while simultaneously converting the light energy into heat. Additionally, the hollow structure of HMnO2 serves as an efficient carrier for IR780. Furthermore, Mn4+ ions released from HMnO2 deplete glutathione (GSH) within the tumor, further amplifying ROS production. This synergistic cascade ultimately culminates in pyroptosis induction through caspase-3-mediated cleavage of gasdermin E (GSDME) upon laser activation. Meanwhile, the depletion of GSH by HMnO2 within the tumor microenvironment (TME) leads to the generation of Mn2+ ions. These Mn2+ ions establish a supportive milieu, which promotes the transformation of bone marrow mesenchymal stem cells (BMSCs) into mature bone cells. This, in turn, promotes the repair of bone defects in rat femurs. Our findings strongly indicate that pyroptosis may be a strategy for osteosarcoma treatment, which presents a robust and versatile approach for targeted therapy and tissue regeneration in this patient population.

Safety Landscape of Therapeutic Nanozymes and Future Research Directions

Oxidative stress and inflammation are at the root of a multitude of diseases. Treatment of these conditions is often necessary but current standard therapies to fight excessive reactive oxygen species (ROS) and inflammation are often ineffective or complicated by substantial safety concerns. Nanozymes are emerging nanomaterials with intrinsic enzyme-like properties that hold great promise for effective cancer treatment, bacterial elimination, and anti-inflammatory/anti-oxidant therapy. While there is rapid progress in tailoring their catalytic activities as evidenced by the recent integration of single-atom catalysts (SACs) to create next-generation nanozymes with superior activity, selectivity, and stability, a better understanding and tuning of their safety profile is imperative for successful clinical translation. This review outlines the current applied safety assessment approaches and provides a comprehensive summary of the safety knowledge of therapeutic nanozymes. Overall, nanozymes so far show good in vitro and in vivo biocompatibility despite considerable differences in their composition and enzymatic activities. However, current safety investigations mostly cover a limited set of basic toxicological endpoints, which do not allow for a thorough and deep assessment. Ultimately, remaining research gaps that should be carefully addressed in future studies are highlighted, to optimize the safety profile of therapeutic nanozymes early in their pre-clinical development.

Pyroptosis-Inducing Biomaterials Pave the Way for Transformative Antitumor Immunotherapy

Pyroptosis can effectively overcome immunosuppression and reactivate antitumor immunity. However, pyroptosis initiation is challenging. First, the underlying biological mechanisms of pyroptosis are complex, and a variety of gasdermin family proteins can be targeted to induce pyroptosis. Second, other intracellular death pathways may also interfere with pyroptosis. The rationally designed gasdermin protein-targeting biomaterials are capable of inducing pyroptosis and have the capacity to stimulate antitumor immune function in a safe and effective manner. This review provides a comprehensive overview of the design, function, and antitumor efficacy of pyroptosis-inducing materials and the associated challenges, with a particular focus on the design options for pyroptosis-inducing biomaterials based on the activation of different gasdermin proteins. This review offers a valuable foundation for the further development of pyroptosis-inducing biomaterials for clinical applications.

Eradication of Large Tumors by Nanoscale Drug Self-Assembly

Most patients with cancer are first diagnosed at an advanced disease stage, when tumors are already large and/or metastases are present. This circumstance has a negative impact on the prognosis and therapeutic effect of anticancer drugs. In this study, it is demonstrated that photosensitizer chlorin e6 and the photochemotherapy drug mitoxantrone self-assemble into relatively stable nanoassemblies (CM NAs) through hydrogen-bonding effect, π-π stacking, and hydrophobic interactions. Administration of CM NAs in combination with 660 nm laser irradiation shows chemotherapeutic, photothermal, and photodynamic effects, causing tumor cell apoptosis and pyroptosis and enabling noninvasive tumor ablation without compromising the surrounding normal tissue. More importantly, treatment with CM NAs increases tumor immunogenicity, leading to a strong and long-term antitumor immune response that eradicates large tumors and provides long-term protection against tumor recurrence on various tumor models.

Ultrathin BSA-Stabilized Black Phosphorous Nanoreactor Boosts Mild-Temperature Photothermal Therapy Through Modulation of Cellular Self-Defense Fate

Mild-temperature photothermal therapy (mild-PTT, 42-45 °C) offers a higher level of biosafety. However, its therapeutic effects are compromised by the heat shock response (HSR), a cellular self-defense mechanism, which triggers the overexpression of heat shock proteins (HSPs) with the capacity of repairing the damaged tumor cells. Herein, this work fabricates a novel nanoreactor by incorporating up-conversion nanoparticles (UCNPs), chlorin e6 (Ce6), and glucose oxidase (GOx) onto the ultrathin black phosphorus nanosheet (BPNS) (denoted as GOx-BUC). This nanoreactor amplifies mild-PTT effects under irradiation with an 808 nm laser, modulating HSPs-mediated cellular self-defense fate. On one hand, upon irradiation with a 980 nm laser, UCNPs can transfer energy to excite Ce6, leading to the generation of ROS burst, which achieves indiscriminate damage to HSPs activity in deeper tumor tissues. On the other hand, GOx can consume glucose, thereby depleting the ATP energy supply and further suppressing HSPs expression. Consequently, GOx-BUC exhibits excellent anti-tumor efficacy under mild temperature in a human colorectal cancer mouse model, resulting in complete tumor inhibition with negligible side effects. This black phosphorous nanoreactor, featuring dual-track HSPs destruction functionality, introduces novel perspectives for enhancing mild-PTT effectiveness while maintaining high biosafety.

Towards precision medicine: design considerations for nanozymes in tumor treatment

Since the discovery of Fe3O4 nanoparticles with enzyme-like activity in 2007, nanozymes have emerged as a promising class of catalysts, offering advantages such as high catalytic efficiency, low cost, mild reaction conditions, and excellent stability. These properties make nanozymes highly suitable for large-scale production. In recent years, the convergence of nanomedicine and nanocatalysis has highlighted the potential of nanozymes in diagnostic and therapeutic applications, particularly in tumor therapy. Despite these advancements, the clinical translation of nanozymes remains hindered by the lack of designs tailored to specific tumor characteristics, limiting their effectiveness in targeted therapy. This review addresses the mechanisms by which nanozymes induce cell death in various tumor types and emphasizes the key design considerations needed to enhance their therapeutic potential. By identifying the challenges and opportunities in the field, this study aims to provide a foundation for future nanozyme development, ultimately contributing to more precise and effective cancer treatments.

Multifunctional Copper-Phenolic Nanopills Achieve Comprehensive Polyamines Depletion to Provoke Enhanced Pyroptosis and Cuproptosis for Cancer Immunotherapy

The overexpression of polyamines in tumor cells contributes to the establishment of immunosuppressive microenvironment and facilitates tumor growth. Here, it have ingeniously designed multifunctional copper-piceatannol/HA nanopills (Cu-Pic/HA NPs) that effectively cause total intracellular polyamines depletion by inhibiting polyamines synthesis, depleting intracellular polyamines, and impairing polyamines uptake, resulting in enhanced pyroptosis and cuproptosis, thus activating a powerful immune response to achieve anti-tumor therapy. Mitochondrial dysfunction resulting from overall intracellular polyamines depletion not only leads to the surge of copper ions in mitochondria, thereby causing the aggregation of toxic proteins to induce cuproptosis, but also triggers the accumulation of reactive oxygen species (ROS) within mitochondria, which further upregulates the expression of zDHHC5 and zDHHC9 to promote the palmitoylation of gasdermin D (GSDMD) and GSDMD-N, ultimately inducing enhanced pyroptosis. Then the occurrence of enhanced pyroptosis and cuproptosis is conductive to remodel the immunosuppressive tumor microenvironment, thus activating anti-tumor immune responses and ultimately effectively inhibiting tumor growth and metastasis. This therapeutic strategy of enhanced pyroptosis and cuproptosis through comprehensive polyamines depletion provides a novel template for cancer immunotherapy.

FeSA‐Ir/Metallene Nanozymes Induce Sequential Ferroptosis‐Pyroptosis for Multi‐Immunogenic Responses Against Lung Metastasis

For cancer metastasis inhibition, the combining of nanozymes with immune checkpoint blockade (ICB) therapy remains the major challenge in controllable reactive oxygen species (ROS) generation for creating effective immunogenicity. Herein, new nanozymes with light-controlled ROS production in terms of quantity and variety are developed by conjugating supramolecular-wrapped Fe single atom on iridium metallene with lattice-strained nanoislands (FeSA-Ir@PF NSs). The Fenton-like catalysis of FeSA-Ir@PF NSs effectively produced •OH radicals in dark, which induced ferroptosis and apoptosis of cancer cells. While under second near-infrared (NIR-II) light irradiation, FeSA-Ir@PF NSs showed ultrahigh photothermal conversion efficiency (𝜂, 75.29%), cooperative robust •OH generation, photocatalytic O2 and 1O2 generation, and caused significant pyroptosis of cancer cells. The controllable ROS generation, sequential cancer cells ferroptosis and pyroptosis, led 99.1% primary tumor inhibition and multi-immunogenic responses in vivo. Most importantly, the inhibition of cancer lung metastasis is completely achieved by FeSA-Ir@PF NSs with immune checkpoint inhibitors, as demonstrated in different mice lung metastasis models, including circulating tumor cells (CTCs) model. This work provided new inspiration for developing nanozymes for cancer treatments and metastasis inhibition.

Nanozymes in cancer immunotherapy: metabolic disruption and therapeutic synergy

Over the past decade, there has been a growing emphasis on investigating the role of immunotherapy in cancer treatment. However, it faces challenges such as limited efficacy, a diminished response rate, and serious adverse effects. Nanozymes, a subset of nanomaterials, demonstrate boundless potential in cancer catalytic therapy for their tunable activity, enhanced stability, and cost-effectiveness. By selectively targeting the metabolic vulnerabilities of tumors, they can effectively intensify the destruction of tumor cells and promote the release of antigenic substances, thereby eliciting immune clearance responses and impeding tumor progression. Combined with other therapies, they synergistically enhance the efficacy of immunotherapy. Hence, a large number of metabolism-regulating nanozymes with synergistic immunotherapeutic effects have been developed. This review summarizes recent advancements in cancer immunotherapy facilitated by nanozymes, focusing on engineering nanozymes to potentiate antitumor immune responses by disturbing tumor metabolism and performing synergistic treatment. The challenges and prospects in this field are outlined. We aim to provide guidance for nanozyme-mediated immunotherapy and pave the way for achieving durable tumor eradication.

Engineering Bimetallic Polyphenol for Mild Photothermal Osteosarcoma Therapy and Immune Microenvironment Remodeling by Activating Pyroptosis and cGAS-STING Pathway

The immunosuppressive tumor microenvironment (ITME) of osteosarcoma (OS) poses a significant obstacle to the efficacy of existing immunotherapies. Despite the attempt of novel immune strategies such as immune checkpoint inhibitors and tumor vaccines, their effectiveness remains suboptimal due to the inherent difficulty in mitigating ITME simultaneously from both the tumor and immune system. The promotion of anti-tumor immunity through the induction of immunogenic cell death and activation of the cGAS-STING pathway has emerged as potential strategies to counter the ITME and stimulate systemic antitumor immune responses. Here, a bimetallic polyphenol-based nanoplatform (Mn/Fe-Gallate nanoparticles coated with tumor cell membranes is presented, MFG@TCM) which combines with mild photothermal therapy (PTT) for reversing ITME via simultaneously inducing pyroptosis in OS cells and activating the cGAS-STING pathway in dendritic cells (DCs). The immunostimulatory pathways, through the syngeneic effect, exerted a substantial positive impact on promoting the secretion of damage-associated molecular patterns (DAMPs) and proinflammatory cytokines, which favors remodeling the immune microenvironment. Consequently, effector T cells led to a notable antitumor immune response, effectively inhibiting the growth of both primary and distant tumors. This study proposes a new method for treating OS using mild PTT and immune mudulation, showing promise in overcoming current treatment limitations.

Photocatalytic Carbon Dots-Triggered Pyroptosis for Whole Cancer Cell Vaccines

Manufacturing whole cancer cell vaccines (WCCV) with both biosafety and efficacy is crucial for tumor immunotherapy. Pyroptotic cancer cells, due to their highly immunogenic properties, present a promising avenue for the development of WCCV. However, the successful development of WCCV based on pyroptotic cancer cells is yet to be accomplished. Here, a facile strategy that utilized photocatalytic carbon dots (CDs) to induce pyroptosis of cancer cells for fabricating WCCV is reported. Photocatalytic CDs are capable of generating substantial amounts of hydroxyl radicals and can effectively decrease cytoplasmic pH values under white light irradiation. This process efficiently triggers cancer cell pyroptosis through the reactive oxygen species (ROS)-mitochondria-caspase 3-gasdermin E pathway and the proton motive force-driven mitochondrial ATP synthesis pathway. Moreover, in vitro, these photocatalytic CDs-induced pyroptotic cancer cells (PCIP) can hyperactivate macrophage (M0-M1) with upregulation of major histocompatibility complex class II expression. In vivo, PCIP induced specific immune-preventive effects in melanoma and breast cancer mouse models through anticancer immune memory, demonstrating effective WCCV. This work provides novel insights for inducing cancer cell pyroptosis and bridges the gap in the fabrication of WCCV based on pyroptotic cancer cells.

Modulating Visible-Light Driven NIR Lanthanide Polymer Photocatalysis for Amplification Detection of Exosomal Proteins and Cancer Diagnosis

Near-infrared (NIR) luminescent lanthanide materials hold great promise for bioanalysis, as they have anti-interference properties. The approach of efficient luminescence is sensitization through a reasonable chromophore to overcome the obstacle of the aqueous phase. The involvement of the surfactant motif is an innovative strategy to arrange the amphiphilic groups to be regularly distributed near the polymer to form a closed sensitized space. Herein, a lanthanide polymer (TCPP-PEI70K-FITC@Yb/SDBS) is designed in which the meso-tetra(4-carboxyphenyl)porphine (TCPP) ligand serves as both a sensitizer and photocatalytic switch. The surfactant sodium dodecyl benzenesulfonate (SDBS) wraps the photosensitive polymers to form a hydrophobic layer, which augments the light-harvesting ability and expedites its photocatalysis. TCPP-PEI70K-FITC@Yb/SDBS is subsequently applied as an amplified photocatalysis toolbox for universally regulating the generation of reactive oxygen species (ROS). Boosting 3,3',5,5'-tetramethylbenzidine (TMB) oxidation to produce blue products, a dual-mode biosensor is fabricated for improving the diagnosis of programmed death ligand-1-positive (PDL1) cancer exosomes. Exosomes were captured by Fe3O4 modified by the PDL1 aptamer, enabling replacement of alkaline phosphatase (ALP)-labeled multiple hybridized chains; then, the isolated ALP triggered a hydrolysis reaction to block the generation of oxTMB. Detection sensitivity improves by 1 order of magnitude through SDBS modulation, down to 104 particles/mL. The sensor performed well clinically in distinguishing cancer patients from healthy individuals, expanding physiological applications of near-infrared lanthanide luminescence.

Water-filtered infrared A radiation hyperthermia combined with immunotherapy for advanced gastrointestinal tumours

This study pioneered the use of WIRA whole-body infrared hyperthermia combined with ICI therapy to treat GIT and verified the feasibility and safety of HIT. The final results showed a DCR of 55.6%, with a median PFS of 53.5 days, median OS of 134 days, and an irAE incidence of 22.2%. Therefore, we believe that HIT can exert multiple synergistic sensitisation effects, thereby providing clinical benefits to patients with advanced GITs, increasing overall safety, and improving patients' QOL.

Bacterial lipase-responsive polydopamine nanoparticles for detection and synergistic therapy of wound biofilms infection

Wound biofilms represent an elusive conundrum in contemporary treatment and diagnostic options, accredited to their escalating antibiotic resistance and interference in chronic wound healing processes. Here, we developed mesoporous polydopamine (mPDA) nanoparticles, and grafted with rhodamine B (Rb) as biofilm lipase responsive detection probe, followed by π - π stacking mediated ciprofloxacin (CIP) loading to create mP-Rb@CIP nanoparticles. mPDA NPs with a melanin structure could quench fluorescence emissions of Rb. Once encountering biofilm in vivo, the ester bond in Rb and mPDA is hydrolyzed by elevated lipase concentrations, triggering the liberation of Rb and restore fluorescence emissions to achieve real-time imaging of biofilm-infected wounds. Afterwards, the 808 nm near-infrared (NIR) illumination initiates a spatiotemporal controlled antibacterial photothermal therapy (PTT), boosting its effectiveness through photothermal-triggered CIP release for synergistic biofilm eradication. The mP-Rb@CIP platform exhibits dual diagnostic and therapeutic functions, efficaciously treating biofilm-infected wounds in vivo and in vitro. Particularly, the mP-Rb@CIP/NIR procedure expedites wound-healing by alleviating oxidative stress, modulating inflammatory mediators, boosting collagen synthesis, and promoting angiogenesis. Taken together, the theranostic nanosystem strategy holds significant potential for addressing wound biofilm-associated infections.

Synergistic quorum sensing inhibition and mild-temperature photothermal therapy of integrated nanoplatform for implant-associated biofilm infections

In current clinical practice, the presence of biofilms poses a significant challenge in the effective elimination of bacterial infections because of the physical and chemical barriers formed by biofilms, which offer persistent protection to bacteria. Here, we developed hollow mesoporous polydopamine (hMP) nanoparticles (NPs) loaded with luteolin (Lu) as a quorum sensing inhibitor, which were further coated with hyaluronic acid (HA) shells to create hMP-Lu@HA NPs. We observed that upon reaching the infection site, the HA shells underwent initial degradation by the hyaluronidase enzyme present in the bacterial infection's microenvironment to expose the hMP-Lu NPs. Subsequently, Lu was released in response to the acidic conditions characteristic of bacterial infections, which effectively hindered and dispersed the biofilm. Moreover, when subjected to near-infrared irradiation, the robust photothermal conversion effect of hMP NPs accelerated the release of Lu and disrupted the integrity of the biofilms by localized heating. This dual action enhanced the eradication of the biofilm infection. Importantly, hMP-Lu@HA NPs also promoted tissue regeneration and healing at the implantation site, concurrently addressing biofilm infection. Taken together, this nanosystem, combined with mild-temperature photothermal therapy and quorum sensing inhibition strategy, holds significant potential for applications in the treatment of implantation-associated infections.

A thermoresponsive nanocomposite integrates NIR-II-absorbing small molecule with lonidamine for pyroptosis-promoted synergistic immunotherapy

Photothermal immunotherapy is regarded as the ideal cancer therapeutic modality to against malignant solid tumors; however, its therapeutic benefits are often modest and require improvement. In this study, a thermoresponsive nanoparticle (BTN@LND) composed of a photothermal agent (PTA) and pyroptosis inducer (lonidamine) were developed to enhance immunotherapy applications. Specifically, our "two-step" donor engineering strategy produced the strong NIR-II-absorbing organic small-molecule PTA (BTN) that exhibited high NIR-II photothermal performance (ε1064 = 1.51 × 104 M-1 cm-1, η = 75.8%), and this facilitates the diagnosis and treatment of deep tumor tissue. Moreover, the fabricated thermally responsive lipid nanoplatform based on BTN efficiently delivered lonidamine to the tumor site and achieved spatiotemporal release triggered by the NIR-II photothermal effect. In vitro and in vivo experiments demonstrated that the NIR-II photothermal therapy (PTT)-mediated on-demand release of cargo effectively faciliated tumor cell pyroptosis, thereby intensifying the immunogenic cell death (ICD) process to promote antitumor immunotherapy. As a result, this intelligent component bearing photothermal and chemotherapy can maximally suppress the growth of tumors, thus providing a promising approach for pyroptosis/NIR-II PTT synergistic therapy against tumors.

Nanocatalysts for modulating antitumor immunity: fabrication, mechanisms and applications

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