Boosting Chemodynamic Therapy by the Synergistic Effect of Co-Catalyze and Photothermal Effect Triggered by the Second Near-Infrared Light

Molybdenum Disulfide Nanocomposites for Cancer Diagnosis and Therapeutics: Biosensors, Bioimaging, and Phototherapy

Molybdenum disulfide (MoS₂) nanomaterials have attracted significant interest in cancer diagnosis and therapy due to their unique physicochemical properties. Due to its extensive surface area and adaptable structure, MoS₂ may engage with pharmaceuticals and biomolecules via covalent and non-covalent interactions. This versatility enhances the sensitivity of identifying specific biomarkers, colloidal stability, and tumor-targeting capabilities. In the near-infrared (NIR) spectrum, MoS₂ exhibits strong optical absorption and efficient photothermal conversion, making it suitable for NIR-driven phototherapy and regulated medication release. Functionalized MoS₂ nanocomposites react differently to the tumor microenvironment, which improves treatment effectiveness by increasing drug accumulation at cancer sites and decreasing off-target effects on healthy tissues. Recent developments in MoS₂-based nanocomposites for cancer detection and treatment are reviewed in this study, with particular attention paid to their uses in photothermal therapy, photodynamic therapy, biosensing, and bioimaging. Additionally, it looks at the difficulties and potential applications of MoS₂ nanocomposites in cancer.

Antibacterial and osteogenic gain strategy on titanium surfaces for preventing implant-related infections

Infection and insufficient osseointegration are the primary factors leading to the failure of titanium-based implants. Surface coating modifications that combine both antibacterial and osteogenic properties are commonly employed strategies. However, the challenge of achieving rapid antibacterial action and consistent osteogenesis with these coatings remains unresolved. In this study, a functional composite coating (PDA/PPy@Cu/Dex) was prepared on titanium surfaces using layer-by-layer self-assembly and electrochemical deposition techniques. The hydroxyl groups grafted by polydopamine's (PDA) self-polymerization and the enhanced conductivity and uniform electric field distribution provided by polypyrrole (PPy) allowed for the even dispersion of copper nanoparticles and dexamethasone (Dex) on the titanium surface. This synergistically coupled the photothermal ion antibacterial properties of copper nanoparticles with the osteogenic promotion of dexamethasone. In vitro antibacterial experiments revealed that the heat generated by photothermal effects and reactive oxygen species enhanced the antibacterial activity of copper ions, reducing the antibacterial time to six h and achieving antibacterial enhancement. In vitro cell experiments showed that the long-term slow release of copper ions and dexamethasone enhanced the osteogenic differentiation of stem cells, thereby achieving osteogenic benefits. Moreover, in vivo toxicity experiments demonstrated that the composite coating had no adverse effects on normal tissues. Therefore, the antibacterial and osteogenic enhancement strategy for titanium surfaces presented in this study offers a new potential approach for preventing implant-associated infections.

Multifunctional Liposomes with Enhanced Stability for Imaging-Guided Cancer Chemodynamic and Photothermal Therapy

Improvements in tumor therapy require a combination of strategies where targeted treatment is critical. We developed a new versatile nanoplatform, MA@E, that generates high levels of reactive oxygen species (ROS) with effective photothermal conversions in the removal of tumors. Enhanced stability liposomes were employed as carriers to facilitate the uniform distribution and stable storage of encapsulated gold nanorods (AuNRs) and Mn-MIL-100 metal-organic frameworks, with efficient delivery of MA@E to the cytoplasm. In the targeted phagocytosis of tumor cells, MA@E can effectively deplete the reduced glutathione (GSH) with increased hydroxyl radicals that combine with Mn2+ released from Mn-MIL-100 to trigger Fenton-like reactions, generating ROS that induces cell apoptosis. Exposure to near-infrared (NIR-II) irradiation results in a AuNRs-induced thermogenic effect that expedites the release of Mn2+ and promotes Fenton-like reactions, achieving increased production of •OH. In the murine tumor model, MA@E effectively removed the implanted tumor tissue within 2 days without any obvious toxic effects. This response is attributed to a synergism involving the photothermal capability of AuNRs and ROS chemodynamic treatment. The proposed MA@E provides a new approach to utilizing unstable nanomaterials in effective tumor therapy.

Ultrasound/magnetic resonance bimodal imaging-guided CD20-targeted multifunctional nanoplatform for photothermal/chemo synergistic therapy of B-cell lymphoma

B-cell lymphoma has a poor prognosis due to difficulties in early diagnosis and the negative effects of systemic chemotherapy. Therefore, there is an urgent need to develop highly accurate and effective theranostic strategies for B-cell lymphoma. In this study, we designed a poly (lactic-co-glycolic acid) (PLGA)-based theranostic nanoplatform (denoted as TscNPs) to achieve ultrasound (US)/magnetic resonance (MR) bimodal imaging-guided photothermal (PTT)/chemo synergistic therapy of B-cell lymphoma. The nanoplatform was conjugated with a CD20 monoclonal antibody specifically targeting B-cell lymphoma to promote tumor accumulation. Encapsulated superparamagnetic iron oxide nanoparticles (SPIONs) as photothermal and MR imaging agents enabled thermal ablation of tumors and imaging-guided tumor therapy. When exposed to near-infrared (NIR) laser, TscNPs generate heat that induces optical droplet vaporization (ODV) of perfluoropentane (PFP), which transforms into microbubbles. This process not only enhanced ultrasound imaging, but also facilitated the release of celastrol (CST) from the nanoplatform, ultimately achieving a PTT/chemo synergistic therapy effect. In the tumor-bearing nude mice model, TscNPs were effectively accumulated in the tumor region. Furthermore, the combined treatment mode of TscNPs and NIR laser irradiation demonstrated a tumor inhibition rate of approximately 96.57 %, which was significantly superior to the rates observed with PTT or chemotherapy alone. These results suggest that the multifunctional theranostic nanoplatform represents a promising new strategy for the therapy of B-cell lymphoma.

Application progress of nanomaterials in the treatment of prostate cancer

Prostate cancer is one of the most common malignant tumors in men, which seriously threatens the survival and quality of life of patients. At present, there are serious limitations in the treatment of prostate cancer, such as drug tolerance, drug resistance and easy recurrence. Sonodynamic therapy and chemodynamic therapy are two emerging tumor treatment methods, which activate specific drugs or sonosensitizers through sound waves or chemicals to produce reactive oxygen species and kill tumor cells. Nanomaterials are a kind of nanoscale materials with many excellent physical properties such as high targeting, drug release regulation and therapeutic monitoring. Sonodynamic therapy and chemodynamic therapy combined with the application of nanomaterials can improve the therapeutic effect of prostate cancer, reduce side effects and enhance tumor immune response. This article reviews the application progress of nanomaterials in the treatment of prostate cancer, especially the mechanism, advantages and challenges of nanomaterials in sonodynamic therapy and chemodynamic therapy, which provides new ideas and prospects for research in this field.

Cuproptosis-based layer-by-layer silk fibroin nanoplatform-loaded PD-L1 siRNA combining photothermal and chemodynamic therapy against metastatic breast cancer

Cuproptosis is a newly identified form of copper-dependent cell death that differs from other known pathways. This discovery provides a new way to explore copper-based nanomaterial applications in cancer therapy. This study used a layer-by-layer self-assembling method to load Cu2-xS nanoparticle (NP) cores with the siRNA of the PD-L1 immune escape-related gene and wrap a silk fibroin (SF) shell to form a multifunctional copper-based SF nanoplatform, denoted as CuS-PEI-siRNA-SFNs. CuS-PEI-siRNA-SFNs induced cuproptosis and exerted an antitumor effect via multiple mechanisms, including photothermal therapy (PTT), chemodynamic therapy (CDT), and immune activation. The presence of significant dihydrolipoamide S-acetyltransferase (DLAT) oligomers in 4T1 cells treated with CuS-PEI-siRNA-SFNs indicated the triggering of cuproptosis. Furthermore, in vivo experimental results showed that CuS-PEI-siRNA-SFNs efficiently accumulated in the tumor tissues of 4T1 tumor-bearing mice inhibited primary tumor and lung metastasis, and displayed excellent biosafety and antitumor activity. This study demonstrated that the synergistic effect of cuproptosis, PTT, CDT, and immune activation showed promise for treating metastatic breast cancer.

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.

NIR-II-Absorbing NDI Polymer with Superior Penetration Depth for Enhanced Photothermal Therapy Efficiency of Hepatocellular Carcinoma

Introduction

Hepatocellular carcinomas (HCC) have a high morbidity and mortality rate, and is difficult to cure and prone to recurrence when it has already developed. Therefore, early detection and efficient treatment of HCC is necessary.

Methods

In this study, we synthesized a novel NDI polymer with uniform size, long-term stability, and high near-infrared two-zone (NIR-II) absorption efficiency, which can greatly enhance the effect of photothermal therapy (PTT) after intravenous injection into Huh-7-tumor bearing mice.

Results

The in vitro and in vivo studies showed that NDI polymer exhibited excellent NIR-guided PTT treatment, and the antitumor effect was approximately 88.5%, with obvious antimetastatic effects.

Conclusion

This study developed an NDI polymer-mediated integrated diagnostic and therapeutic modality for NIR-II fluorescence imaging and photothermal therapy.

Enhancing the Photosensitivity of Hypocrellin A by Perylene Diimide Metallacage-Based Host-Guest Complexation for Photodynamic Therapy

The development of supramolecular hosts which can efficiently encapsulate photosensitizers to improve the photodynamic efficacy holds great promise for cancer therapy. Here, we report two perylene diimide-based metallacages that can form stable host-guest complexes with planar conjugated molecules including polycyclic aromatic hydrocarbons and photosensitizers (hypocrellin A). Such host-guest complexation not only prevents the aggregation of photosensitizers in aqueous environments, but also offers fluorescence resonance energy transfer (FRET) from the metallacage to the photosensitizers to further improve the singlet oxygen generation (ΦΔ = 0.66). The complexes are further assembled with amphiphilic polymers, forming nanoparticles with improved stability for anticancer study. Both in vitro and in vivo studies indicate that the nanoparticles display excellent anticancer activities upon light irradiation, showing great potential for cancer photodynamic therapy. This study provides a straightforward and effective approach for enhancing the photosensitivity of conventional photosensitizers via host-guest complexation-based FRET, which will open a new avenue for host-guest chemistry-based supramolecular theranostics.

Sensitize Tumor Immunotherapy: Immunogenic Cell Death Inducing Nanosystems

Low immunogenicity of tumors poses a challenge in the development of effective tumor immunotherapy. However, emerging evidence suggests that certain therapeutic approaches, such as chemotherapy, radiotherapy, and phototherapy, can induce varying degrees of immunogenic cell death (ICD). This ICD phenomenon leads to the release of tumor antigens and the maturation of dendritic cells (DCs), thereby enhancing tumor immunogenicity and promoting immune responses. However, the use of a single conventional ICD inducer often fails to achieve in situ tumor ablation and establish long-term anti-tumor immune responses. Furthermore, the induction of ICD induction varies among different approaches, and the distribution of the therapeutic agent within the body influences the level of ICD and the occurrence of toxic side effects. To address these challenges and further boost tumor immunity, researchers have explored nanosystems as inducers of ICD in combination with tumor immunotherapy. This review examines the mechanisms of ICD and different induction methods, with a specific focus on the relationship between ICD and tumor immunity. The aim is to explore the research advancements utilizing various nanomaterials to enhance the body's anti-tumor effects by inducing ICD. This paper aims to contribute to the development and clinical application of nanomaterial-based ICD inducers in the field of cancer immunotherapy by providing important theoretical guidance and practical references.

An insight into the dual role of MoS2-based nanocarriers in anticancer drug delivery and therapy

Over the years, nanomaterials have been exploited as drug delivery systems and therapeutic agents in cancer treatment. Special emphasis has been placed on structure and shape-mediated drug loading and release. Functional materials, including molybdenum disulfide (MoS2), have shown promising results because of their tunable structure and unmatched physicochemical properties. Specifically, easy surface functionalization and high drug adsorption ability make them ideal candidates. Although the large surface area of nanosheets/nanoflakes may result in high drug loading, the encapsulation efficiency is better for MoS2 nanoflower structures. Due to its high targeting abilities, the loading of chemotherapeutic drugs onto MoS2 may minimize nonspecific cellular death and undesired side effects. Furthermore, due to their strong light-absorption ability, MoS2 nanostructures have been widely exploited as photothermal and photodynamic therapeutic agents. The unexplored dimensions of cancer therapy, including chemodynamic (Fenton-like reaction) and piezo-catalytic (ultrasound-mediated reactive oxygen generation), have been recently unlocked, in which the catalytic properties of MoS2 are utilized to generate toxic free radicals to eliminate cancer. Intriguingly, combining these therapeutic modalities often results in high therapeutic efficacy at low doses and minimizes side effects. With a plethora of recent studies, a thorough analysis of current findings is crucial. Therefore, this review discusses the major advances in this field of research. A brief commentary on the limitations/future outlook/ethical issues of the clinical translation of MoS2-mediated cancer treatments is also deliberated. Overall, in our observations, the MoS2-based nanoformulations hold great potential for future cancer therapy applications. STATEMENT OF SIGNIFICANCE: Development of nanomedicines based on MoS2 has opened new avenues in cancer treatment. The MoS2 with different morphologies (nanosheet/nanoflower/QDs) has shown promising results in controlled and targeted drug delivery, leading to minimized side effects and increased therapeutic efficacy. While existing reviews have primarily focused on the optical/thermal properties utilized in photodynamic/photothermal therapy, the outstanding catalytic properties of MoS2 utilized in cancer therapies (chemodynamic/piezo-catalytic) are often overlooked. This review critically highlights and praises/criticizes individual articles reporting the MoS2-based nanoplatforms for cancer therapy applications. Additionally, MoS2-based combined therapies for synergistic effects are discussed. Furthermore, a brief commentary on the future prospects for clinical translations is also deliberated, which is appealing to various research communities engaged in cancer theranostics and biomedical sciences research.

Photothermal and ferroptosis synergistic therapy for liver cancer using iron-doped polydopamine nanozymes

An innovative nanozyme, iron-doped polydopamine (Fe-PDA), which integrates iron ions into a PDA matrix, conferred peroxidase-mimetic activity and achieved a substantial photothermal conversion efficiency of 43.5 %. Fe-PDA mediated the catalysis of H2O2 to produce toxic hydroxyl radicals (•OH), thereby facilitating lipid peroxidation in tumour cells and inducing ferroptosis. Downregulation of solute carrier family 7 no. 11 (SLC7A11) and solute carrier family 3 no. 2 (SLC3A2) in System Xc- resulted in decreased intracellular glutathione (GSH) production and inactivation of the nuclear factor erythroid 2-related factor 2 (NRF2)-glutathione peroxidase 4 (GPX4) pathway, contributing to ferroptosis. Moreover, the application of photothermal therapy (PTT) enhanced the effectiveness of chemodynamic therapy (CDT), accelerating the Fenton reaction for targeted tumour eradication while sparing adjacent non-cancerous tissues. In vivo experiments revealed that Fe-PDA significantly hampered tumour progression in mice, emphasizing the potential of the dual-modality treatment combining CDT and PTT for future clinical oncology applications.

Immunoantitumor Activity and Oxygenation Effect Based on Iron-Copper-Doped Folic Acid Carbon Dots

Cancer metastasis and recurrence are closely associated with immunosuppression and a hypoxic tumor microenvironment. Chemodynamic therapy (CDT) and photothermodynamic therapy (PTT) have been shown to induce immunogenic cell death (ICD), effectively inhibiting cancer metastasis and recurrence when combined with immune adjuvants. However, the limited efficacy of Fenton's reaction and suboptimal photothermal effect present significant challenges for successfully inducing ICD through CDT and PTT. This paper described the synthesis and immunoantitumor activity of the novel iron-copper-doped folic acid carbon dots (CFCFB). Copper-doped folic acid carbon dots (Cu-FACDs) were initially synthesized via a hydrothermal method, using folic acid and copper gluconate as precursors. Subsequently, the nanoparticles CFCFB were obtained through cross-linking and self-assembly of Cu-FACDs with ferrocene dicarboxylic acid (FeDA) and 3-bromopyruvic acid (3BP). The catalytic effect of carbon dots in CFCFB enhanced the activity of the Fenton reaction, thereby promoting CDT-induced ICD and increasing the intracellular oxygen concentration. Additionally, 3BP inhibited cellular respiration, further amplifying the oxygen concentration. The photothermal conversion efficiency of CFCFB reached 55.8%, which significantly enhanced its antitumor efficacy through photothermal therapy. Immunofluorescence assay revealed that treatment with CFCFB led to an increased expression of ICD markers, including calreticulin (CRT) and ATP, as well as extracellular release of HMGB-1, indicating the induction of ICD by CFCFB. Moreover, the observed downregulation of ARG1 expression indicates a transition in the tumor microenvironment from an immunosuppressive state to an antitumor state following treatment with CFCFB. The upregulation of IL-2 and CD8 expression facilitated the differentiation of effector T cells, resulting in an augmented population of CD8+ T cells, thereby indicating the activation of systemic immune response.

RuCu Nanosheets with Ultrahigh Nanozyme Activity for Chemodynamic Therapy

Nanoenzymes have been widely explored for chemodynamic therapy (CDT) in cancer treatment. However, poor catalytic efficiency of nanoenzymes, especially in the tumor microenvironment with insufficient H2 O2 and mild acidity, limits the effect of CDT. Herein, a new ultrathin RuCu nanosheet (NS) based nanoenzyme which has a large specific surface area and abundant channels and defects is developed. The RuCu NSs show superb catalytic efficiency for the oxidation of peroxidase substrate H2 O2 at a wide range of pH and their catalytic efficiency (kcat /Km = 177.2 m-1  s-1 ) is about 14.9 times higher than that of the single-atom catalyst FeN3 P. Besides being an efficient nanozyme as peroxidase, the RuCu NSs possess other two enzyme activities, not only disproportionating superoxide anion to produce H2 O2 but also consuming glutathione to keep a high concentration of H2 O2 in the tumor microenvironment for Fenton reaction. With these advantages, the RuCu NSs exhibit good performance to kill cancer cells and inhibit tumor growth in mice, demonstrating a promising potential as new CDT reagent.

Nanoparticle-Based Photothermal Therapy for Breast Cancer Noninvasive Treatment

Rapid advancements in materials science and nanotechnology, intertwined with oncology, have positioned photothermal therapy (PTT) as a promising noninvasive treatment strategy for cancer. The breast's superficial anatomical location and aesthetic significance render breast cancer a particularly pertinent candidate for the clinical application of PTT following melanoma. This review comprehensively explores the research conducted on the various types of nanoparticles employed in PTT for breast cancer and elaborates on their specific roles and mechanisms of action. The integration of PTT with existing clinical therapies for breast cancer is scrutinized, underscoring its potential for synergistic outcomes. Additionally, the mechanisms underlying PTT and consequential modifications to the tumor microenvironment after treatment are elaborated from a medical perspective. Future research directions are suggested, with an emphasis on the development of integrative platforms that combine multiple therapeutic approaches and the optimization of nanoparticle synthesis for enhanced treatment efficacy. The goal is to push the boundaries of PTT toward a comprehensive, clinically applicable treatment for breast cancer.

l-Arginine-Modified CoWO4 /FeWO4 S-Scheme Heterojunction Enhances Ferroptosis against Solid Tumor

Ferroptosis has recently attracted much attention as an anti-tumor therapy. Evidence suggests that ferroptosis can induce oxidative stress and accumulation of lethal lipid peroxides in cancer cells, leading to cell damage. However, unsuitable pH, H2 O2 levels, and high glutathione (GSH) expression in the tumor microenvironment hinder the development of ferroptosis-mediated therapy. In this study, an l-arginine (l-arg)-modified CoWO4 /FeWO4 (CFW) S-scheme heterojunction is strategically designed and constructed for ultrasound (US)-triggered sonodynamic- and gas therapy-induced ferroptosis. CFW not only has excellent Fenton-catalytic activity, outstanding GSH consumption capacity, and excellent ability to overcome tumor hypoxia, but its S-scheme heterostructure can also avoid the rapid combination of electron (e) and hole (h+ ) pairs, thereby enhancing the sonodynamic effects. As a precursor of nitric oxide (NO), l-arg is modified on the surface of CFW (CFW@l-arg) to achieve controlled NO release under US irradiation, thereby enhancing ferroptosis. In addition, poly(allylamine hydrochloride) is further modified on the surface of CFW@l-arg to stabilize l-arg and achieve controllable NO release. Both in vitro and in vivo results demonstrate that such a multifunctional therapeutic nanoplatform can achieve high therapeutic efficacy through sonodynamic and gas therapy-enhanced ferroptosis. This designed oncotherapy nanoplatform provides new inspiration for ferroptosis-mediated therapy.

Copper Single-Atom Jellyfish-like Nanomotors for Enhanced Tumor Penetration and Nanocatalytic Therapy

Single-atom catalysts with extraordinary catalytic activity have been receiving great attention in tumor therapy. However, most single-atom catalysts lack self-propulsion properties, restricting them from actively approaching cancer cells or penetrating the interior of tumors. Herein, we design N-doped jellyfish-like mesoporous carbon nanomotors coordinated with single-atom copper (Cu-JMCNs). It is a combination of single-atom nanocatalytic medicine and nanomotor self-propulsion for cancer therapy. The Cu single atom can catalyze H₂O₂ into toxic hydroxyl radical (^•OH) for chemodynamic therapy (CDT). Near-infrared light triggers Cu-JMCNs to achieve self-thermophoretic motion because of the jellyfish-like asymmetric structure and photothermal property of carbon, which significantly improves the cellular uptake and the penetration of three-dimensional tumors. In vivo experiments indicate that the combination of single-atom Cu for CDT and near-infrared light propulsion can achieve over 85% tumor inhibition rate. This work sheds light on the development of advanced nanomotors with single-atom catalysts for biomedical applications.

Multifunctional nanomedicines-enabled chemodynamic-synergized multimodal tumor therapy via Fenton and Fenton-like reactions

Chemodynamic therapy (CDT) is well-known for using the tumor microenvironment to activate the Fenton reaction or Fenton-like reaction to generate strong oxidative hydroxyl radicals for tumor-specific treatment. It is highly selective and safe, without depth limitation of tissue penetration, and shows its potential as a new green therapeutic method with great clinical application. However, the catalytic efficiency of reagents involved in the Fenton reaction is severely affected by the inherent microenvironmental limitations of tumors and the strict Fenton reaction-dependent conditions. With the increasing application of nanotechnology in the medical field, combined therapies based on different types of functional nanomaterials have opened up new avenues for the development of next-generation CDT-enhanced system. This review will comprehensively exemplify representative results of combined therapies of CDT with other antitumor therapies such as chemotherapy, phototherapy, sonodynamic therapy, radiation therapy, magnetic hyperthermia therapy, immunotherapy, starvation therapy, gas therapy, gene therapy, oncosis therapy, or a combination thereof for improving antitumor efficiency from hundreds of the latest literature, introduce strategies such as the ingenious design of nanomedicines and tumor microenvironment regulations to enhance the combination therapy, and further summarize the challenges and future perspective of CDT-based multimodal anticancer therapy.

A multiphoton transition activated iron based metal organic framework for synergistic therapy of photodynamic therapy/chemodynamic therapy/chemotherapy for orthotopic gliomas

Although photodynamic therapy (PDT) has exhibited good potential in therapy of gliomas, the limited penetration depth of light and the obstacle of the blood-brain barrier (BBB) lead to unsatisfactory treatment effects. Herein, a multifunctional nanodrug (UMD) was constructed with up-conversion nanoparticles (NaGdF₄:Yb,Tm@NaYF₄:Yb,Nd@NaYF₄, UCNPs) as the core, the photosensitizer NH₂-MIL-53 (Fe) as the shell and a carrier for loading chemotherapy drug doxorubicin hydrochloride (Dox) for synergistic therapy of gliomas. Lactoferrin (LF) was finally modified on the surface of the UMD to endow it with the ability to traverse the BBB and target cells (UMDL). The UCNP core can convert 808 nm near-infrared (NIR) light to ultraviolet light (UV light) for exciting NH₂-MIL-53 (Fe), achieving NIR-mediated PDT. In addition, Fe³⁺ on the surface of the NH₂-MIL-53 (Fe) shell could be reduced to Fe²⁺ in a tumor microenvironment (TME), and then reacted with over-expressed H₂O₂ in the TME to generate hydroxyl radicals (˙OH) for chemodynamic therapy (CDT). The Dox drug could be released in response to acidic conditions in the TME, inhibiting the growth of gliomas with low side effects. The synergistic effect of PDT/CDT/chemotherapy leads to effective suppression of orthotopic gliomas.

A Light-Responsive Injectable Hydrogel with Remodeling Tumor Microenvironment for Light-Activated Chemodynamic Therapy

Chemodynamic therapy (CDT) based on Fenton-like reaction is often limited by the tumor microenvironment (TME), which has insufficient hydrogen peroxide, and single CDT treatment is often less efficacious. To overcome these limitations, a hydrogel-based system is designed to enhance the redox stress (EOH) by loading the composite nanomaterial Cu-Hemin-Au, into the agarose hydrogels. The hydrogels can reach the tumor site upon intratumoral injection, and then coagulate and stay for extended period. Once irradiated with near-infrared light, the Cu-Hemin-Au act as a photothermal agent to convert the light energy into heat, and the EOH gradually heated up and softened, releasing the Cu-Hemin-Au residing in it to achieve photothermal therapy (PTT). Benefiting from the glucose oxidase (GOx)-like activity of the Au nanoparticles, glucose in the tumor cells is largely consumed, and hydrogen peroxide (H₂ O₂ ) is generated in situ, and then Cu-Hemin-Au react with sufficient H₂ O₂ to generate a large amount of reactive oxygen species, which promote the complete inhibition of tumor growth in mice during the treatment cycle. The hydrogel system for the synergistic enhancement of oxidative stress achieves good PTT/CDT synergy, providing a novel inspiration for the next generation of hydrogels for application in antitumor therapy.

Tumor Microenvironment-Adaptive Nanoplatform Synergistically Enhances Cascaded Chemodynamic Therapy

Chemodynamic therapy (CDT), a noninvasive strategy, has emerged as a promising alternative to conventional chemotherapy for treating tumors. However, its therapeutic effect is limited by the amount of H₂O₂, pH value, the hypoxic environment of tumors, and it has suboptimal tumor-targeting ability. In this study, tumor cell membrane-camouflaged mesoporous Fe₃O₄ nanoparticles loaded with perfluoropentane (PFP) and glucose oxidase (GOx) are used as a tumor microenvironment-adaptive nanoplatform (M-mFeP@O₂-G), which synergistically enhances the antitumor effect of CDT. Mesoporous Fe₃O₄ nanoparticles are selected as inducers for photothermal and Fenton reactions and as nanocarriers. GOx depletes glucose within tumor cells for starving the cells, while producing H₂O₂ for subsequent ·OH generation. Moreover, PFP, which can carry O₂, relieves hypoxia in tumor cells and provides O₂ for the cascade reaction. Finally, the nanoparticles are camouflaged with osteosarcoma cell membranes, endowing the nanoparticles with homologous targeting and immune escape abilities. Both in vivo and in vitro evaluations reveal high synergistic therapeutic efficacy of M-mFeP@O₂-G, with a desirable tumor-inhibition rate (90.50%), which indicates the great potential of this platform for clinical treating cancer.

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GOx and PFP were loaded in mFe₃O₄ to form a TME-adaptive nanoplatform and synergistically enhance the cascaded reactions.

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Tumor cell membranes, endowing the nanoparticles with homologous targeting and immune escape abilities.

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The nanoparticles had excellent combined chemodynamic therapy, starvation therapy and photothermal tumor therapy effect.

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Tumor cell membranes coated nanoparticles improved cell uptake and had a desirable tumor-inhibition rate.

Copper nanocrystalline-doped folic acid-based super carbon dots for an enhanced antitumor effect in response to tumor microenvironment stimuli

Chemodynamic therapy (CDT) is a promising cancer treatment strategy to induce tumor cell apoptosis with harmful reactive oxygen species (ROS), yet over-expression of glutathione (GSH) in the tumor microenvironment (TME) severely depletes the ROS and limits the CDT efficacy. Copper-containing materials could efficiently decrease the level of GSH in the TME. In this study, copper nanocrystalline-doped folic acid-based super carbon dots (FA-CDs@Cu^x) were prepared to realize an enhanced antitumor effect in response to tumor microenvironment stimuli. Folic acid (FA) was used as a source of carbon dots to improve the targetability of nanomaterials to tumor cells with over-expressed FA receptors. Copper existed mainly in the form of copper nanocrystals, which were embedded on the carbon core by in situ reduction of Cu²⁺ by gluconic acid. The prepared composites were found to reduce the intracellular H₂O₂ into hydroxyl radicals (˙OH) and consume GSH efficiently in tumor cells. Copper-doping enabled the CDs to absorb near-infrared light and to give a high photothermal transformation efficiency (54.3%) and high singlet oxygen atom yield (56.83%), endowing the super carbon dots with synergetic CDT/PTT/PDT functions in response to the TME and NIR stimuli, which have been investigated systematically by in vitro and in vivo biological experiments.

A novel dual MoS2/FeGA quantum dots endowed injectable hydrogel for efficient photothermal and boosting chemodynamic therapy

Due to its responsiveness to the tumour microenvironment (TME), chemodynamic therapy (CDT) based on the Fenton reaction to produce cytotoxic reactive oxygen species (ROS) to destroy tumor has drawn more interest. However, the Fenton's reaction potential for therapeutic use is constrained by its modest efficacy. Here, we develop a novel injectable hydrogel system (FMH) on the basis of FeGA/MoS2 dual quantum dots (QDs), which uses near-infrared (NIR) laser in order to trigger the synergistic catalysis and photothermal effect of FeGA/MoS2 for improving the efficiency of the Fenton reaction. Mo4+ in MoS2 QDs can accelerate the conversion of Fe3+ to Fe2+, thereby promoting the efficiency of Fenton reaction, and benefiting from the synergistically enhanced CDT/PTT, FMH combined with NIR has achieved good anti-tumour effects in vitro and in vivo experiments. Furthermore, the quantum dots are easily metabolized after treatment because of their ultrasmall size, without causing any side effects. This is the first report to study the co-catalytic effect of MoS2 and Fe3+ at the quantum dot level, as well as obtain a good PTT/CDT synergy, which have implications for future anticancer research.

NIR-responsive polydopamine-based calcium carbonate hybrid nanoparticles delivering artesunate for cancer chemo-photothermal therapy

Artesunate (AS), the first-line treatment of malaria with a satisfactory safety profile, has been repurposed as a potential anticancer candidate as it mainly generates reactive oxygen species (ROS) through its intrinsic endoperoxide bridge reacting with ferrous-based catalysts to suppress cancer cell growth. However, further clinical translation of AS is hindered by the attenuated anticancer efficacy due to insufficient ROS generation. Herein, we rationally integrated hydrophobic-modified AS (hAS) with biomimetic polydopamine (PDA) and biomineral calcium carbonate to fabricate high AS-loaded nanomedicine (Ca-PDA/hAS@PEG) for cancer chemo-photothermal therapy, which exerted anticancer effects in the following ways: (1) the heat was generated when PDA was irradiated by near-infrared (NIR) light for photothermal therapy. Meanwhile, the increased temperature accelerated the production of ROS from hAS, thus enhancing the anticancer efficacy of hAS-based chemotherapy; (2) hAS-mediated chemotherapy boosted the cancer inhibition effect of photothermal therapy by arousing the intracellular ROS levels in the presence of endogenous ferrous ions and sensitizing cancer cells to thermal ablation; (3) the integration of calcium carbonate into the nanoparticle facilitated the pH-responsive drug release for precise treatment. Such hybrid nanoparticles exhibited a combinational antitumor effect of photothermal therapy and chemotherapy in vivo with no systemic toxicity. Taken together, our work presents a facile strategy to improve the anticancer efficacy of AS by combining chemical modification and photothermal therapy-assisted endoperoxide bridge cleavage, which may offer opportunities to pave the way for clinical translation of AS-based nanomedicines. STATEMENT OF SIGNIFICANCE: The clinical translation of artesunate (AS) is hindered by the attenuated anticancer efficacy due to insufficient ROS generation. Herein, we rationally integrated hydrophobic-modified AS (hAS) with biomimetic polydopamine (PDA) and biomineral calcium carbonate to fabricate high AS-loaded nanomedicine (Ca-PDA/hAS@PEG) for improved cancer chemo-photothermal therapy. The heat generated from PDA in response to near-infrared light irradiation could locally ablate tumor as well as accelerate the production of ROS by hAS, thus enhancing the anticancer efficacy of hAS-based chemotherapy. On the other hand, hAS-based chemotherapy amplified the intracellular oxidative stress, sensitizing cancer cells to thermal ablation. Our work presents a facile strategy to improve the anticancer efficacy of AS by combining chemical modification and photothermal therapy-assisted endoperoxide bridge cleavage.

Two-Dimensional Nanomaterial-based catalytic Medicine: Theories, advanced catalyst and system design

Two-dimensional nanomaterial-based catalytic medicines that associate the superiorities of novel catalytic mechanisms with nanotechnology have emerged as absorbing therapeutic strategies for cancer therapy. Catalytic medicines featuring high efficiency and selectivity have been widely used as effective anticancer strategies without applying traditional nonselective and highly toxic chemodrugs. Moreover, two-dimensional nanomaterials are characterized by distinctive physicochemical properties, such as a sizeable bandgap, good conductivity, fast electron transfer and photoelectrochemical activity. The introduction of two-dimensional nanomaterials into catalytic medicine provides a more effective, controllable, and precise antitumor strategy. In this review, different types of two-dimensional nanomaterial-based catalytic nanomedicines are generalized, and their catalytic theories, advanced catalytic pathways and catalytic nanosystem design are also discussed in detail. Notably, future challenges and obstacles in the design and further clinical transformation of two-dimensional nanomaterial-based catalytic nanomedicine are prospected.

Engineering single-atom catalysts toward biomedical applications

Due to inherent structural defects, common nanocatalysts always display limited catalytic activity and selectivity, making it practically difficult for them to replace natural enzymes in a broad scope of biologically important applications. By decreasing the size of the nanocatalysts, their catalytic activity and selectivity will be substantially improved. Guided by this concept, the advances of nanocatalysts now enter an era of atomic-level precise control. Single-atom catalysts (denoted as SACs), characterized by atomically dispersed active sites, strikingly show utmost atomic utilization, precisely located metal centers, unique metal-support interactions and identical coordination environments. Such advantages of SACs drastically boost the specific activity per metal atom, and thus provide great potential for achieving superior catalytic activity and selectivity to functionally mimic or even outperform natural enzymes of interest. Although the size of the catalysts does matter, it is not clear whether the guideline of "the smaller, the better" is still correct for developing catalysts at the single-atom scale. Thus, it is clearly a new, urgent issue to address before further extending SACs into biomedical applications, representing an important branch of nanomedicine. This review begins by providing an overview of recent advances of synthesis strategies of SACs, which serve as a basis for the discussion of emerging achievements in improving the enzyme-like catalytic properties at an atomic level. Then, we carefully compare the structures and functions of catalysts at various scales from nanoparticles, nanoclusters, and few-atom clusters to single atoms. Contrary to conventional wisdom, SACs are not the most catalytically active catalysts in specific reactions, especially those requiring multi-site auxiliary activities. After that, we highlight the unique roles of SACs toward biomedical applications. To appreciate these advances, the challenges and prospects in rapidly growing studies of SACs-related catalytic nanomedicine are also discussed in this review.

Multifunctional nanocarrier with self-catalytic production of nitric oxide for photothermal and gas-combined therapy of tumor

Single treatment often faces the problem that it cannot completely eradicate tumor and inhibit the tumor metastasis. In order to overcome this shortcoming, multi-modal tumor treatment has attracted widespread attention. In the present article, based on ascorbyl palmitate (PA) and l-arginine (l-Arg), a multifunctional nanocarrier is designed for synergetic treatment of tumor with photothermal and nitric oxide (NO) gas therapy. Firstly, PA and l-Arg were self-assembled to form novel functional micelles, PL, with high biosafety using electrostatic interaction and hydrogen bonding. The functional micelles could self-catalyze to produce NO at the tumor site. Then, Ag₂S quantum dots having fluorescence imaging and photothermal properties were encapsulated to obtain the nanocarrier, A@PL. The results show that A@PL had a hydrated size of around 78 nm and presented good stability within 30 d. Moreover, in vitro studies indicate that it was efficient with regards to NO self-generating capacity, whereas the photothermal conversion efficiency was as high as 34% under near-infrared light irradiation. The cytotoxicity results show that, when the concentration of A@PL was as high as 2 mM, the survival rate of 3 T3 cells was still 78.23%, proving that the probe has good safety characteristics. Fluorescence imaging results show that its maximum enrichment can be achieved at the tumor site after tail vein injection for 3 h, and out of the body after 24 h, indicating good internal circulation. The in vivo studies show that the rate of inhibition of tumor using the nanocarrier was as high as 98%, and almost overcame the problem of tumor recurrence caused by single treatment, thus presenting a significant tumor treatment effect. This new multifunctional nanocarrier with self-catalytic production of NO provides a new idea for the efficient treatment of tumors.

Chemodynamic Therapy via Fenton and Fenton-Like Nanomaterials: Strategies and Recent Advances

Chemodynamic therapy (CDT), a novel cancer therapeutic strategy defined as the treatment using Fenton or Fenton-like reaction to produce •OH in the tumor region, was first proposed by Bu, Shi, and co-workers in 2016. Recently, with the rapid development of Fenton and Fenton-like nanomaterials, CDT has attracted tremendous attention because of its unique advantages: 1) It is tumor-selective with low side effects; 2) the CDT process does not depend on external field stimulation; 3) it can modulate the hypoxic and immunosuppressive tumor microenvironment; 4) the treatment cost of CDT is low. In addition to the Fe-involved CDT strategies, the Fenton-like reaction-mediated CDT strategies have also been proposed, which are based on many other metal elements including copper, manganese, cobalt, titanium, vanadium, palladium, silver, molybdenum, ruthenium, tungsten, cerium, and zinc. Moreover, CDT has been combined with other therapies like chemotherapy, radiotherapy, phototherapy, sonodynamic therapy, and immunotherapy for achieving enhanced anticancer effects. Besides, there have also been studies that extend the application of CDT to the antibacterial field. This review introduces the latest advancements in the nanomaterials-involved CDT from 2018 to the present and proposes the current limitations as well as future research directions in the related field.

Recent advances of cancer chemodynamic therapy based on Fenton/Fenton-like chemistry

Applying Fenton chemistry in the tumor microenvironment (TME) for cancer therapy is the most significant feature of chemodynamic therapy (CDT). Owing to the mild acid and overexpressed H2O2 in TME, more cytotoxic hydroxyl radicals (˙OH) are generated in tumor cells via Fenton and Fenton-like reactions. Without external stimulus and drug resistance generation, reactive oxygen species (ROS)-mediated CDT exhibits a specific and desirable anticancer effect and has been seen as a promising strategy for cancer therapy. However, optimizing the treatment efficiency of CDT in TME is still challenging because of the limited catalytic efficiency of CDT agents and the strong cancer antioxidant capacity in TME. Hence, scientists are trying their best to design and fabricate many more CDT agents with excellent catalytic activity and remodeling TME for optimal CDT. In this perspective, the latest progress of CDT is discussed, with some representative examples presented. Consequently, promising strategies for further optimizing the efficiency of CDT guided by Fenton chemistry are provided. Most importantly, several feasible ways of developing CDT in the future are offered for reference.

Recent advances in multifunctional nanomaterials for photothermal-enhanced Fenton-based chemodynamic tumor therapy

Photothermal (PT)-enhanced Fenton-based chemodynamic therapy (CDT) has attracted a significant amount of research attention over the last five years as a highly effective, safe, and tumor-specific nanomedicine-based therapy. CDT is a new emerging nanocatalyst-based therapeutic strategy for the in situ treatment of tumors via the Fenton reaction or Fenton-like reaction, which has got fast progress in recent years because of its high specificity and activation by endogenous substances. A variety of multifunctional nanomaterials such as metal-, metal oxide-, and metal-sulfide-based nanocatalysts have been designed and constructed to trigger the in situ Fenton or Fenton-like reaction within the tumor microenvironment (TME) to generate highly cytotoxic hydroxyl radicals (•OH), which is highly efficient for the killing of tumor cells. However, research is still required to enhance the curative outcomes and minimize its side effects. Specifically, the therapeutic efficiency of certain CDTs is still hindered by the TME, including low levels of endogenous hydrogen peroxide (H2O2), overexpression of reduced glutathione (GSH), and low catalytic efficacy of Fenton or Fenton-like reactions (pH 5.6-6.8), which makes it difficult to completely cure cancer using monotherapy. For this reason, photothermal therapy (PTT) has been utilized in combination with CDT to enhance therapeutic efficacy. More interestingly, tumor heating during PTT not only causes damage to the tumor cells but can also accelerate the generation of •OH via the Fenton and Fenton-like reactions, thus enhancing the CDT efficacy, providing more effective cancer treatment when compared with monotherapy. Currently, synergistic PT-enhanced CDT using multifunctional nanomaterials with both PT and chemodynamic properties has made enormous progress in cancer theranostics. However, there has been no comprehensive review on this subject published to date. In this review, we first summarize the recent progress in PT-enhanced Fenton-based CDT for cancer treatment. We then discuss the potential and challenges in the future development of PT-enhanced Fenton-based nanocatalytic tumor therapy for clinical application.

Synergistic strategy with hyperthermia therapy based immunotherapy and engineered exosomes−liposomes targeted chemotherapy prevents tumor recurrence and metastasis in advanced breast cancer

Advanced breast cancer with recurrent and distal organ metastasis is aggressive and incurable. The current existing treatment strategies for advanced breast cancer are difficult to achieve synergistic treatment of recurrent tumors and distant metastasis, resulting in poor clinical outcomes. Herein, a synergistic therapy strategy composed of biomimetic tumor‐derived exosomes (TEX)‐Liposome‐paclitaxel (PTX) with lung homing properties and gold nanorods (GNR)‐PEG, was designed, respectively. GNR‐PEG, with well biocompatibility, cured recurrent tumors effectively by thermal ablation under the in situ NIR irradiation. Meanwhile, GNR‐mediated thermal ablation activated the adaptive antitumor immune response, significantly increased the level of CD8⁺ T cells in lungs and the concentration of serum cytokines (tumor necrosis factor‐α, interlekin‐6, and interferon‐γ). Subsequently, TEX‐Liposome‐PTX preferentially accumulated in lung tissues due to autologous tumor‐derived TEX with inherent specific affinity to lung, resulting in a better therapeutic effect on lung metastasis tumors with the assistance of adaptive immunotherapy triggered by GNR in vivo. The enhanced therapeutic efficacy in advanced breast cancer was a combination of thermal ablation, adaptive antitumor immunotherapy, and targeted PTX chemotherapy. Hence, the synergistic strategy based on GNR and TEX‐Liposome provides selectivity to clinical treatment of advanced breast cancer with recurrent and metastasis.

ICG@ZIF-8/PDA/Ag composites as chemo-photothermal antibacterial agents for efficient sterilization and enhanced wound disinfection

Bacterial infection has increasingly affected people's lives, therefore it is significant to explore novel antibacterial agents and strategies for efficient disinfection. Herein, we designed ZIF-8 based composites ICG@ZIF-8/PDA/Ag, which encapsulate photothermal agent indocyanine green (ICG) and grow polydopamine (PDA) on their surface for in situ reduction to generate Ag nanoparticles. With 20 min of 808 nm laser irradiation at 1.5 W cm^-2, 100 μg mL^-1 ICG@ZIF-8/PDA/Ag exhibited 100% bactericidal effects toward E. coli and S. aureus bacteria resulting from both hyperthermia of ICG and PDA and chemical toxicity of the released Ag and Zn ions. When the bacterial incubation period was extended to 12 h, the minimum bactericidal concentration (MBC) of ICG@ZIF-8/PDA/Ag was reduced to 6.25 μg mL^-1, and this extremely low MBC was due to the long-term chemo-photothermal combinational effect induced by NIR irradiation. Additionally, the composites successfully promote the healing of S. aureus infected wounds on mice. This work constructed photo-responsive antibacterial composites that realize chemo-photothermal synergistic therapy.

Copper single-atom catalysts with photothermal performance and enhanced nanozyme activity for bacteria-infected wound therapy

Nanozymes have become a new generation of antibiotics with exciting broad-spectrum antibacterial properties and negligible biological toxicity. However, their inherent low catalytic activity limits their antibacterial properties. Herein, Cu single-atom sites/N doped porous carbon (Cu SASs/NPC) is successfully constructed for photothermal-catalytic antibacterial treatment by a pyrolysis-etching-adsorption-pyrolysis (PEAP) strategy. Cu SASs/NPC have stronger peroxidase-like catalytic activity, glutathione (GSH)-depleting function, and photothermal property compared with non-Cu-doped NPC, indicating that Cu doping significantly improves the catalytic performance of nanozymes. Cu SASs/NPC can effectively induce peroxidase-like activity in the presence of H2O2, thereby generating a large amount of hydroxyl radicals (•OH), which have a certain killing effect on bacteria and make bacteria more susceptible to temperature. The introduction of near-infrared (NIR) light can generate hyperthermia to fight bacteria, and enhance the peroxidase-like catalytic activity, thereby generating additional •OH to destroy bacteria. Interestingly, Cu SASs/NPC can act as GSH peroxidase (GSH-Px)-like nanozymes, which can deplete GSH in bacteria, thereby significantly improving the sterilization effect. PTT-catalytic synergistic antibacterial strategy produces almost 100% antibacterial efficiency against Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA). In vivo experiments show a better PTT-catalytic synergistic therapeutic performance on MRSA-infected mouse wounds. Overall, our work highlights the wide antibacterial and anti-infective bio-applications of Cu single-atom-containing catalysts.

MoS2-based nanocomposites for cancer diagnosis and therapy

Molybdenum is a trace dietary element necessary for the survival of humans. Some molybdenum-bearing enzymes are involved in key metabolic activities in the human body (such as xanthine oxidase, aldehyde oxidase and sulfite oxidase). Many molybdenum-based compounds have been widely used in biomedical research. Especially, MoS2-nanomaterials have attracted more attention in cancer diagnosis and treatment recently because of their unique physical and chemical properties. MoS2 can adsorb various biomolecules and drug molecules via covalent or non-covalent interactions because it is easy to modify and possess a high specific surface area, improving its tumor targeting and colloidal stability, as well as accuracy and sensitivity for detecting specific biomarkers. At the same time, in the near-infrared (NIR) window, MoS2 has excellent optical absorption and prominent photothermal conversion efficiency, which can achieve NIR-based phototherapy and NIR-responsive controlled drug-release. Significantly, the modified MoS2-nanocomposite can specifically respond to the tumor microenvironment, leading to drug accumulation in the tumor site increased, reducing its side effects on non-cancerous tissues, and improved therapeutic effect. In this review, we introduced the latest developments of MoS2-nanocomposites in cancer diagnosis and therapy, mainly focusing on biosensors, bioimaging, chemotherapy, phototherapy, microwave hyperthermia, and combination therapy. Furthermore, we also discuss the current challenges and prospects of MoS2-nanocomposites in cancer treatment.

Cancer therapeutic strategies based on metal ions

As a necessary substance to maintain the body's normal life activities, metal ions are ubiquitous in organisms and play a major role in various complex physiological and biochemical processes, such as material transportation, energy conversion, information transmission, metabolic regulation, etc. Their abnormal distribution/accumulation in cells can interfere with these processes, causing irreversible physical damage to cells or activating biochemical reactions to induce cell death. Therefore, metal ions can be exploited against a wide spectrum of cancers with high efficiency and without drug resistance, which can effectively inhibit the growth of cancer cells by triggering biocatalysis, breaking the osmotic balance, affecting metabolism, interfering with signal transduction, damaging DNA, etc. This perspective systematically summarizes the latest research progress of metal ion-based anti-tumor therapy, and emphasizes the challenges and development directions of this type of therapeutic strategy, hoping to provide a general implication for future research.

Carambola-like Bi2Te3 superstructures with enhanced photoabsorption for highly efficient photothermal therapy in the second near-infrared biowindow

Photothermal therapy (PTT) stimulated by light in the second near-infrared (NIR-II) biowindow shows great superiorities in the penetration ability of tissue and maximum permissible exposure (MPE). Exploring new photothermal agents with good optical absorbance in the NIR-II region is highly desirable for efficient cancer therapy. Herein, we successfully prepare carambola-like bismuth telluride (Bi₂Te₃) superstructures modified with PEGylated phospholipid (Bi₂Te₃@PEG) for CT imaging-guided PTT in the NIR-II biowindow. Attributing to their superstructures, Bi₂Te₃@PEG exhibited enhanced photoabsorption with higher photothermal conversion efficiency (55.3% for 1064 nm) compared with that of Bi₂Te₃ nanoparticles. Furthermore, the good X-ray attenuation capacity of Bi endows Bi₂Te₃@PEG with an outstanding performance as computed tomography (CT) contrast agents. Bi₂Te₃@PEG superstructures have been confirmed to effectively eliminate tumor in vitro and in vivo with negligible long-term toxicities, offering them great potential to act as theranostic platforms for cancer diagnosis and treatment.

PolyTLR7/8a-conjugated, antigen-trapping gold nanorods elicit anticancer immunity against abscopal tumors by photothermal therapy-induced in situ vaccination

Nanovaccine can elicit antigen-specific immune responses against tumor cells expressing homologous antigens and has attracted enormous attention in cancer immunotherapy. However, tumor heterogeneity remarkably hinders the development of nanovaccines. Here we demonstrate that PTT-induced in situ vaccination cancer therapy can elicit potent antitumor immunity against disseminated and metastatic tumors. Gold nanorods (AuNRs) covalently coupled with amphiphilic polyTLR7/8a and MMP-2-sensitive R9-PEG conjugate (AuNRs-IMQD-R9-PEG) were developed as a new biocompatible PTT agent with favorable photothermal efficiency and stability. Importantly, AuNRs-IMQD-R9-PEG can effectively absorb tumor-derived protein antigens, forming nanovaccines directly in vivo and enhance the activation of host dendritic cells (DCs), thereby amplifying adaptive antitumor T-cell responses, triggering effector memory immune responses, and activating innate antitumor immunity. Remarkably, peri-tumoral administration of low-dose multifunctional AuNRs followed by non-invasive near-infrared (NIR) laser irradiation enables efficient tandem PTT-vaccination treatment modality that can inhibit local as well as untreated distant and metastatic tumors in mice inoculated with poorly immunogenic, highly metastatic 4T1 tumors. Our findings indicate that AuNRs-IMQD-R9-PEG-mediated in situ cancer vaccination provides a powerful immunotherapy characterized by markedly increased infiltration of effector CD8⁺ T, natural killer T (NKT) cells in tumors and long-term animal survival, thus, offering a promising therapeutic strategy for advanced, disseminated cancers.

Preparation of ROS active and photothermal responsive hydroxyapatite nanoplatforms for anticancer therapy

Photothermal responsive nanoplatforms are attracting for photothermal therapy (PTT) of cancer. Herein, we propose a strategy to prepare IR-780 modified hydroxyapatite (HAP) nanorods as photothermic agents (HAP@IR-780). The results demonstrated that the obtained HAP@IR-780 was photothermal responsive under near-infrared laser irradiation the photothermal conversion efficiency was 69.3%, and it remained photostability after 4 cycles of irradiation. This advantage overcomes the optical instability of IR780. MTT and cellular uptake research proved that HAP@IR-780 was biocompatible in appropriate concentration range (0-20 μg/mL) without laser irradiation. Concentration-dependent internalization and reactive oxygen species (ROS) related apoptosis of HAP@IR-780 for MCF-7 cells were observed. Animal experiments showed that the gathered HAP@IR-780 at the tumor site reached a photothermal responsive temperature up to 57.9 °C, which could almost ablate the tumor with volumes as large as 1500 mm3. In general, our photothermal material has good photothermal conversion characteristics, and may have the least safety problems while showing excellent therapeutic effects. Therefore, HAP@IR-780 has a brilliant prospect in the field of tumor photothermal therapy.

A microenvironment-mediated Cu2O–MoS2 nanoplatform with enhanced Fenton-like reaction activity for tumor chemodynamic/photothermal therapy

Chemodynamic therapy (CDT) with selective therapeutic and minimal side effects has attracted increasing attention in recent years.