Colorectal Tumor Microenvironment-Activated Bio-Decomposable and Metabolizable Cu2 O@CaCO3 Nanocomposites for Synergistic Oncotherapy

Multifaceted Carbonized Metal-Organic Frameworks Synergize with Immune Checkpoint Inhibitors for Precision and Augmented Cuproptosis Cancer Therapy

The discovery of cuproptosis, a copper-dependent mechanism of programmed cell death, has provided a way for cancer treatment. However, cuproptosis has inherent limitations, including potential cellular harm, the lack of targeting, and insufficient efficacy as a standalone treatment. Therefore, exogenously controlled combination treatments have emerged as key strategies for cuproptosis-based oncotherapy. In this study, a Cu2-xSe@cMOF nanoplatform was constructed for combined sonodynamic/cuproptosis/gas therapy. This platform enabled precise cancer cotreatment, with external control allowing the selective induction of cuproptosis in cancer cells. This approach effectively prevented cancer metastasis and recurrence. Furthermore, Cu2-xSe@cMOF was combined with the antiprogrammed cell death protein ligand-1 antibody (aPD-L1), and this combination maximized the advantages of cuproptosis and immune checkpoint therapy. Additionally, under ultrasound irradiation, the H2Se gas generated from Cu2-xSe@cMOF induced cytotoxicity in cancer cells. Further, it generated reactive oxygen species, which hindered cell survival and proliferation. This study reports an externally controlled system for cuproptosis induction that combines a carbonized metal-organic framework with aPD-L1 to enhance cancer treatment. This precision and reinforced cuproptosis cancer therapy platform could be valuable as an effective therapeutic agent to reduce cancer mortality and morbidity in the future.

Biocompatible Copper-Based Nanocomposites for Combined Cancer Therapy

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

Copper in colorectal cancer: From copper-related mechanisms to clinical cancer therapies

Copper, a trace element and vital cofactor, plays a crucial role in the maintenance of biological functions. Recent evidence has established significant correlations between copper levels, cancer development and metastasis. The strong redox-active properties of copper offer both benefits and disadvantages to cancer cells. The intestinal tract, which is primarily responsible for copper uptake and regulation, may suffer from an imbalance in copper homeostasis. Colorectal cancer (CRC) is the most prevalent primary cancer of the intestinal tract and is an aggressive malignant disease with limited therapeutic options. Current research is primarily focused on the relationship between copper and CRC. Innovative concepts, such as cuproplasia and cuproptosis, are being explored to understand copper-related cellular proliferation and death. Cuproplasia is the regulation of cell proliferation that is mediated by both enzymatic and nonenzymatic copper-modulated activities. Whereas, cuproptosis refers to cell death induced by excess copper via promoting the abnormal oligomerisation of lipoylated proteins within the tricarboxylic acid cycle, as well as by diminishing the levels of iron-sulphur cluster proteins. A comprehensive understanding of copper-related cellular proliferation and death mechanisms offers new avenues for CRC treatment. In this review, we summarise the evolving molecular mechanisms, ranging from abnormal intracellular copper concentrations to the copper-related proteins that are being discovered, and discuss the role of copper in the pathogenesis, progression and potential therapies for CRC. Understanding the relationship between copper and CRC will help provide a comprehensive theoretical foundation for innovative treatment strategies in CRC management.

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

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

Application and progress of nanozymes in antitumor therapy

Tumors remain one of the major threats to public health and there is an urgent need to design new pharmaceutical agents for their diagnosis and treatment. In recent years, due to the rapid development of nanotechnology, biotechnology, catalytic science, and theoretical computing, subtlety has gradually made great progress in research related to tumor diagnosis and treatment. Compared to conventional drugs, enzymes can improve drug distribution and enhance drug enrichment at the tumor site, thereby reducing drug side effects and enhancing drug efficacy. Nanozymes can also be used as tumor tracking imaging agents to reshape the tumor microenvironment, providing a versatile platform for the diagnosis and treatment of malignancies. In this paper, we review the current status of research on enzymes in oncology and analyze novel oncology therapeutic approaches and related mechanisms. To date, a large number of nanomaterials, such as noble metal nanomaterials, nonmetallic nanomaterials, and carbon-based nanomaterials, have been shown to be able to function like natural enzymes, particularly with significant advantages in tumor therapy. In light of this, the authors in this review have systematically summarized and evaluated the construction, enzymatic activity, and their characteristics of nanozymes with respect to current modalities of tumor treatment. In addition, the application and research progress of different types of nicknames and their features in recent years are summarized in detail. We conclude with a summary and outlook on the study of nanozymes in tumor diagnosis and treatment. It is hoped that this review will inspire researchers in the fields of nanotechnology, chemistry, biology, materials science and theoretical computing, and contribute to the development of nano-enzymology.

Nanocatalytic Anti-Tumor Immune Regulation

Immunotherapy has brought a new dawn for human being to defeat cancer. Although existing immunotherapy regimens (CAR-T, etc.) have made breakthroughs in the treatments of hematological cancer and few solid tumors such as melanoma, the therapeutic efficacy on most solid tumors is still far from being satisfactory. In recent years, the researches on tumor immunotherapy based on nanocatalytic materials are under rapid development, and significant progresses have been made. Nanocatalytic medicine has been demonstrated to be capable of overcoming the limitations of current clinicnal treatments by using toxic chemodrugs, and exhibits highly attractive advantages over traditional therapies, such as the enhanced and sustained therapeutic efficacy based on the durable catalytic activity, remarkably reduced harmful side-effects without using traditional toxic chemodrugs, and so on. Most recently, nanocatalytic medicine has been introduced in the immune-regulation for disease treatments, especially, in the immunoactivation for tumor therapies. This article presents the most recent progresses in immune-response activations by nanocatalytic medicine-initiated chemical reactions for tumor immunotherapy, and elucidates the mechanism of nanocatalytic medicines in regulating anti-tumor immunity. By reviewing the current research progress in the emerging field, this review will further highlight the great potential and broad prospects of nanocatalysis-based anti-tumor immune-therapeutics.

Improved Immune Response for Colorectal Cancer Therapy Triggered by Multifunctional Nanocomposites with Self-Amplifying Antitumor Ferroptosis

Ferroptosis, as a type of regulated cell death, can trigger the release of damage-associated molecular patterns from cancer cells and lead to the enhancement of immune recognition. Fenton reaction-mediated chemodynamic therapy could initiate ferroptosis by generating lipid peroxides, but its efficiency would be greatly restricted by the insufficient H2O2 and antioxidant system within the tumor. Herein, this work reports the successful preparation of H2O2 self-supplied and glutathione (GSH)-depletion therapeutic nanocomposites (Cu2O@Au) through in situ growth of Au nanoparticles on the surface of cuprous oxide (Cu2O) nanospheres. Upon delivery into cancer cells, the released Cu2O could consume endogenous H2S within colorectal cancer cells to form Cu31S16 nanoparticles, while the released Au NPs could catalyze glucose to generate H2O2 and gluconic acid. The self-supplying endogenous H2O2 and lower acidity could amplify the Cu ion-induced Fenton-like reaction. Meanwhile, the consumption of glucose would reduce GSH generation by disrupting the pentose phosphate pathway. Additionally, the Cu2+/Cu+ catalytic cycle promotes the depletion of GSH, leading to lipid peroxide accumulation and ferroptosis. It was found that the onset of ferroptosis triggered by Cu2O@Au could initiate immunologic cell death, promote dendritic cell maturation and T-cell infiltration, and finally enhance the antitumor efficacy of the PD-L1 antibody. In summary, this collaborative action produces a remarkable antitumor effect, which provides a promising treatment strategy for colorectal cancer.

pH-Responsive Hyaluronic Acid Nanomicelles for Photodynamic /Chemodynamic Synergistic Therapy Trigger Immunogenicity and Oxygenation

Cancer metastasis and invasion are closely related to tumor cell immunosuppression and intracellular hypoxia. Activation of immunogenicity and intracellular oxygenation are effective strategies for cancer treatment. In this study, multifunctional nanomicelle hyaluronic acid and cinnamaldehyde is self-assembled into nanomicelles (HPCNPs) were constructed for immunotherapy and tumor cell oxygenation. The Schiff base was constructed of HPCNPs with pyropheophorbide a-Cu (PPa-Cu). HPCNPs are concentrated in tumor sites under the guidance of CD44 proteins, and under the stimulation of tumor environment (weakly acidic), the Schiff base is destroyed to release free PPa. HPCNPs with photodynamic therapeutic functions and chemokinetic therapeutic functions produce a large number of reactive oxygen species (1O2 and •OH) under exogenous (laser) and endogenous (H2O2) stimulations, causing cell damage, and then inducing immunogenic cell death (ICD). ICD markers (CRT and ATP) and immunoactivity markers (IL-2 and CD8) were characterized by immunofluorescence. Downregulation of Arg1 protein proved that the tumor microenvironment changed from immunosuppressive type (M2) to antitumor type (M1). The oxidation of glutathione by HPCNP cascades to amplify the concentration of reactive oxygen species. In situ oxygenation by HPCNPs based on a Fenton-like reaction improves the intracellular oxygen level. In vitro and in vivo experiments demonstrated that HPCNPs combined with an immune checkpoint blocker (α-PD-L1) effectively ablated primary tumors, effectively inhibited the growth of distal tumors, and increased the oxygen level in tumor cells.

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

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

Biomimetic-gasdermin-protein-expressing nanoplatform mediates tumor-specific pyroptosis for cancer immunotherapy

Pyroptosis, mediated by gasdermin proteins, has shown excellent efficacy in facilitating cancer immunotherapy. The strategies commonly used to induce pyroptosis suffer from a lack of tissue specificity, resulting in the nonselective activation of pyroptosis and consequent systemic toxicity. Moreover, pyroptosis activation usually depends on caspase, which can induce inflammation and metabolic disorders. In this study, inspired by the tumor-specific expression of SRY-box transcription factor 4 (Sox4) and matrix metalloproteinase 2 (MMP2), we constructed a doubly regulated plasmid, pGMD, that expresses a biomimetic gasdermin D (GSDMD) protein to induce the caspase-independent pyroptosis of tumor cells. To deliver pGMD to tumor cells, we used a hyaluronic acid (HA)-shelled calcium carbonate nanoplatform, H-CNP@pGMD, which effectively degrades in the acidic endosomal environment, releasing pGMD into the cytoplasm of tumor cells. Upon the initiation of Sox4, biomimetic GSDMD was expressed and cleaved by MMP2 to induce tumor-cell-specific pyroptosis. H-CNP@pGMD effectively inhibited tumor growth and induced strong immune memory effects, preventing tumor recurrence. We demonstrate that H-CNP@pGMD-induced biomimetic GSDMD expression and tumor-specific pyroptosis provide a novel approach to boost cancer immunotherapy.

Recent Developments in CaCO3 Nano-Drug Delivery Systems: Advancing Biomedicine in Tumor Diagnosis and Treatment

Calcium carbonate (CaCO3), a natural common inorganic material with good biocompatibility, low toxicity, pH sensitivity, and low cost, has a widespread use in the pharmaceutical and chemical industries. In recent years, an increasing number of CaCO3-based nano-drug delivery systems have been developed. CaCO3 as a drug carrier and the utilization of CaCO3 as an efficient Ca2+ and CO2 donor have played a critical role in tumor diagnosis and treatment and have been explored in increasing depth and breadth. Starting from the CaCO3-based nano-drug delivery system, this paper systematically reviews the preparation of CaCO3 nanoparticles and the mechanisms of CaCO3-based therapeutic effects in the internal and external tumor environments and summarizes the latest advances in the application of CaCO3-based nano-drug delivery systems in tumor therapy. In view of the good biocompatibility and in vivo therapeutic mechanisms, they are expected to become an advancing biomedicine in the field of tumor diagnosis and treatment.

Application of calcium overload-based ion interference therapy in tumor treatment: strategies, outcomes, and prospects

Low selectivity and tumor drug resistance are the main hinderances to conventional radiotherapy and chemotherapy against tumor. Ion interference therapy is an innovative anti-tumor strategy that has been recently reported to induce metabolic disorders and inhibit proliferation of tumor cells by reordering bioactive ions within the tumor cells. Calcium cation (Ca2+) are indispensable for all physiological activities of cells. In particular, calcium overload, characterized by the abnormal intracellular Ca2+ accumulation, causes irreversible cell death. Consequently, calcium overload-based ion interference therapy has the potential to overcome resistance to traditional tumor treatment strategies and holds promise for clinical application. In this review, we 1) Summed up the current strategies employed in this therapy; 2) Described the outcome of tumor cell death resulting from this therapy; 3) Discussed its potential application in synergistic therapy with immunotherapy.

A TME-activated nano-catalyst for triple synergistic therapy of colorectal cancer

Colorectal cancer cells are highly heterogeneous and exhibit various drug resistances, making personalized treatment necessary. This typically involves a combination of different treatment modalities such as surgery, radiation, and chemotherapy to increase patient survival. Inspired by this, synergistic therapy, which combines multiple modalities into a single nanotherapeutic drug, shows promise in treating cancer. In this study, a nano-catalyst based on calcium peroxide (CaO2) and the chemotherapeutic drug doxorubicin hydrochloride (DOX) co-loaded into HPB nanoparticles (HPB@CaO2/DOX-PAA) was developed to achieve synergistic cancer treatment through chemodynamic/chemo/photothermal (CDT/CT/PTT) mechanisms. After being endocytosed by cancer cells, the nano-catalyst decomposes, releasing cargo. During near-infrared light irradiation, HPB induces a photothermal effect, DOX exhibits significant RNA and DNA destruction capabilities, meanwhile CaO2 produces a large amount of H2O2 in the moderately acidic TME, which combines with Fe2+ ions derived from HPB to form the highly toxic •OH in a Fenton-like reaction, enhancing the chemodynamic treatment. Assays conducted ex vivo and in vivo have exhibited the efficacy of this triple synergistic therapeutic regimen, indicating its potential clinical application.

Hydrogen sulfide responsive nanoplatforms: Novel gas responsive drug delivery carriers for biomedical applications

Hydrogen sulfide (H2S) is a toxic, essential gas used in various biological and physical processes and has been the subject of many targeted studies on its role as a new gas transmitter. These studies have mainly focused on the production and pharmacological side effects caused by H2S. Therefore, effective strategies to remove H2S has become a key research topic. Furthermore, the development of novel nanoplatforms has provided new tools for the targeted removal of H2S. This paper was performed to review the association between H2S and disease, related H2S inhibitory drugs, as well as H2S responsive nanoplatforms (HRNs). This review first analyzed the role of H2S in multiple tissues and conditions. Second, common drugs used to eliminate H2S, as well as their potential for combination with anticancer agents, were summarized. Not only the existing studies on HRNs, but also the inhibition H2S combined with different therapeutic methods were both sorted out in this review. Furthermore, this review provided in-depth analysis of the potential of HRNs about treatment or detection in detail. Finally, potential challenges of HRNs were proposed. This study demonstrates the excellent potential of HRNs for biomedical applications.

Manipulating calcium homeostasis with nanoplatforms for enhanced cancer therapy

Calcium ions (Ca2+) are indispensable and versatile metal ions that play a pivotal role in regulating cell metabolism, encompassing cell survival, proliferation, migration, and gene expression. Aberrant Ca2+ levels are frequently linked to cell dysfunction and a variety of pathological conditions. Therefore, it is essential to maintain Ca2+ homeostasis to coordinate body function. Disrupting the balance of Ca2+ levels has emerged as a potential therapeutic strategy for various diseases, and there has been extensive research on integrating this approach into nanoplatforms. In this review, the current nanoplatforms that regulate Ca2+ homeostasis for cancer therapy are first discussed, including both direct and indirect approaches to manage Ca2+ overload or inhibit Ca2+ signalling. Then, the applications of these nanoplatforms in targeting different cells to regulate their Ca2+ homeostasis for achieving therapeutic effects in cancer treatment are systematically introduced, including tumour cells and immune cells. Finally, perspectives on the further development of nanoplatforms for regulating Ca2+ homeostasis, identifying scientific limitations and future directions for exploitation are offered.

Ultrasound activated probe for disease imaging and therapy In-Vivo

Sonodynamic therapy (SDT) is the use of ultrasound (US) to excite sonosensitizers to produce reactive oxygen species (ROS) to induce tumor cell death, thereby achieving therapeutic purposes. Based on the strong tissue penetration ability of ultrasound, SDT can realize the treatment of deeper tumors, and it is targeted, can be specifically concentrated at the tumor site, and has little impact on surrounding normal tissues. It has broad clinical transformation prospects. Therefore, sonosensitizers are the key to SDT, and the exploration of sonosensitizers with excellent therapeutic performance has received great attention. We reviewed the development of ultrasound-inspired sound sensitizers for imaging and treatment. First, different types of sonosensitizers are introduced, the construction and performance of inorganic, organic and hybrid types of sonosensitizers are evaluated, followed by a review of different image-guided SDT, and finally the key problems and solutions in this field are discussed in detail.

Targeted Nanoparticles: the Smart Way for the Treatment of Colorectal Cancer

Colorectal cancer (CRC) is a widespread cancer that starts in the digestive tract. It is the third most common cause of cancer deaths around the world. The World Health Organization (WHO) estimates an expected death toll of over 1 million cases annually. The limited therapeutic options as well as the drawbacks of the existing therapies necessitate the development of non-classic treatment approaches. Nanotechnology has led the evolution of valuable drug delivery systems thanks to their ability to control drug release and precisely target a wide variety of cancers. This has also been extended to the treatment of CRC. Herein, we shed light on the pertinent research that has been performed on the potential applications of nanoparticles in the treatment of CRC. The various types of nanoparticles in addition to their properties, applications, targeting approaches, merits, and demerits are discussed. Furthermore, innovative therapies for CRC, including gene therapies and immunotherapies, are also highlighted. Eventually, the research gaps, the clinical potential of such delivery systems, and a future outlook on their development are inspired.

Copper in Cancer: from transition metal to potential target

In recent years, with the continuous in-depth exploration of the molecular mechanisms of tumorigenesis, numerous potential new targets for cancer treatment have been identified, some of which have been further developed in clinical practice and have produced positive outcomes. Notably, researchers' initial motivation for studying copper metabolism in cancer stems from the fact that copper is a necessary trace element for organisms and is closely connected to body growth and metabolism. Moreover, over the past few decades, considerable progress has been made in understanding the molecular processes and correlations between copper and cancer. Certain achievements have been made in the development and use of relevant clinical medications. The concept of "cuproptosis," a novel concept that differs from previous forms of cell death, was first proposed by a group of scientists last year, offering fresh perspectives on the targeting capabilities of copper in the treatment of cancer. In this review, we introduced the fundamental physiological functions of copper, the key components of copper metabolism, and a summary of the current research contributions on the connection between copper and cancer. In addition, the development of new copper-based nanomaterials and their associated mechanisms of action are discussed. Finally, we described how the susceptibility of cancer cells to this metallic nutrition could be leveraged to further improve the existing cancer treatment paradigm in the new setting.

An erythrocyte membrane-camouflaged fluorescent covalent organic framework for starving/nitric oxide/immunotherapy of triple-negative breast cancer

It is a great challenge to effectively treat triple-negative breast cancer (TNBC) due to lack of therapeutic targets and drug resistance of systemic chemotherapy. Rational design of nanomedicine with good hemocompatibility is urgently desirable for combination therapy of TNBC. Herein, an erythrocyte membrane-camouflaged fluorescent covalent organic framework (COF) loaded with an NO donor (hydroxyurea, Hu), glucose oxidase (GOx) and cytosine-phosphate-guanine oligonucleotides (CPG) (COF@HGC) was developed for imaging-guided starving/nitric oxide (NO)/immunization synergistic treatment of TNBC. The substances of HGC are easily co-loaded onto the COF due to the ordered pore structure and large surface area. And a folic acid-modified erythrocyte membrane (FEM) is coated on the surface of COF@HGC to improve targeted therapy and haemocompatibility. When COF@HGC@FEM is internalized into tumor cells, hemoglobin (Hb) on FEM and GOx loaded on the COF can trigger cascade reactions to kill tumor cells due to the simultaneous production of NO and exhaustion of glucose. Meanwhile, the COF with excellent fluorescence properties can be used as a self-reporter for bioimaging. Furthermore, the CPG can reprogram tumor-associated macrophages from tumor-supportive phenotype to anti-tumor phenotype and enhance immunotherapy. Through the "three-in-one" strategy, the biomimetic nanoplatform can effectively inhibit tumor growth and reprogram the tumor immunosuppression microenvironment in the TNBC mouse model.

Rationally designed calcium carbonate multifunctional trap for contaminants adsorption

Adsorption technology has been widely developed to control environmental pollution, which plays an important role in the sustainable development of modern society. Calcium carbonate (CaCO3) is characterized by its flexible pore design and functional group modification, which meet the high capacity and targeting requirements of adsorption. Therefore, its charm of "small materials for great use" makes it a suitable candidate for adsorption. Firstly, we comprehensively review the research progress of controlled synthesis and surface modification of CaCO3, and its application for adsorbing contaminants from water and air. Then, we systematically examine the structure-effect relationship between CaCO3 adsorbents and contaminants, while also intrinsic mechanism of remarkable capacity and targeted adsorption. Finally, from the perspective of material design and engineering application, we offer insightful discussion on the prospects and challenges of calcium carbonate adsorbents, providing a valuable reference for the further research in this field.

Photothermal therapy of copper incorporated nanomaterials for biomedicine

Studies have reported on the significance of copper incorporated nanomaterials (CINMs) in cancer theranostics and tissue regeneration. Given their unique physicochemical properties and tunable nanostructures, CINMs are used in photothermal therapy (PTT) and photothermal-derived combination therapies. They have the potential to overcome the challenges of unsatisfactory efficacy of conventional therapies in an efficient and non-invasive manner. This review summarizes the recent advances in CINMs-based PTT in biomedicine. First, the classification and structure of CINMs are introduced. CINMs-based PTT combination therapy in tumors and PTT guided by multiple imaging modalities are then reviewed. Various representative designs of CINMs-based PTT in bone, skin and other organs are presented. Furthermore, the biosafety of CINMs is discussed. Finally, this analysis delves into the current challenges that researchers face and offers an optimistic outlook on the prospects of clinical translational research in this field. This review aims at elucidating on the applications of CINMs-based PTT and derived combination therapies in biomedicine to encourage future design and clinical translation.

Calcium carbonate-actuated ion homeostasis perturbator for oxidative damage-augmented Ca2+/Mg2+ interference therapy

Ion homeostasis distortion through exogenous overload or underload of intracellular ion species has become an arresting therapeutic approach against malignant tumor. Nevertheless, treatment outcomes of such ion interference are always compromised by the intrinsic ion homeostasis maintenance systems in cancer cells. Herein, an ion homeostasis perturbator (CTC) is facilely designed by co-encapsulation of carvacrol (CAR) and meso-tetra-(4-carboxyphenyl)porphine (TCPP) into pH-sensitive nano-CaCO3, aiming to disrupt the self-defense mechanism during the process of ion imbalance. Upon the endocytosis of CTC into tumor cells, lysosomal acidity can render the decomposition of CaCO3, resulting in the instant Ca2+ overload and CO2 generation in cytoplasm. Simultaneously, CaCO3 disintegration triggers the release of CAR and TCPP, which are devoted to TRPM7 inhibition and sonosensitization, respectively. The malfunction of TRPM7 can impede the influx of Mg2+ and allow unrestricted influx of Ca2+ based on the antagonism relationship between Mg2+ and Ca2+, leading to an aggravated Ca2+/Mg2+ dyshomeostasis through ion channel deactivation. In another aspect, US-triggered cavitation can be significantly enhanced by the presence of inert CO2 microbubbles, further amplifying the generation of reactive oxygen species. Such oxidative damage-augmented Ca2+/Mg2+ interference therapy effectively impairs the mitochondrial function of tumor, which may provide useful insights in cancer therapy.

Redox Homeostasis Disruptors Based on Metal-Phenolic Network Nanoparticles for Chemo/Chemodynamic Synergistic Tumor Therapy through Activating Apoptosis and Cuproptosis

The combination of chemo/chemodynamic therapy is a promising strategy for improving antitumor efficacy. Herein, metal-phenolic network nanoparticles (NPs) self-assembled from copper ions and gallic acid (Cu-GA) are developed to evoke apoptosis and cuproptosis for synergistic chemo/chemodynamic therapy. The Cu-GA NPs are biodegraded in response to the highly expressed glutathione (GSH) in tumor cells, resulting in the simultaneous release of Cu+ and GA. The intracellular GSH content is dramatically reduced by the released GA, rendering the tumor cells incapable of scavenging reactive oxygen species (ROS) and more susceptible to cuproptosis. Meanwhile, ROS levels within the tumor cells are significantly increased by the Fenton-like reaction of released Cu+ , which disrupts redox homeostasis and achieves apoptosis-related chemodynamic therapy. Moreover, massive accumulation of Cu+ in the tumor cells further induces aggregation of lipoylated dihydrolipoamide S-acetyltransferase and downregulation of iron-sulfur cluster protein, activating cuproptosis to enhance the antitumor efficacy of Cu-GA NPs. The experiments in vivo further demonstrate that Cu-GA NPs exhibited the excellent biosafety and superior antitumor capacity, which can efficiently inhibit the growth of tumors due to the activation by the tumor specific GSH and hydrogen peroxide. These Cu-based metal-phenolic network NPs provide a potential strategy to build up efficient and safe cancer therapy.

Copper indium selenium nanomaterials for photo-amplified immunotherapy through simultaneously enhancing cytotoxic T lymphocyte recruitment and M1 polarization of macrophages

Photoactivated immunotherapy has promising therapeutic efficacy for treating malignancies, especially metastatic tumors. In this study, an erythrocyte membrane-encapsulated copper indium selenium (RCIS) semiconductor nanomaterial was developed to eliminate primary and metastatic tumors, in which copper ions can induce chemodynamic performance, and the narrow band gap endows RCIS with the properties of near-infrared (NIR) light-activated photothermal and photodynamic amplified immunotherapy. Furthermore, RCIS can be used as a nanocarrier to form RNCIS nanoparticles (NPs) by loading NLG919, which blocks the indoleamine 2,3-dioxygenase-1. Under NIR light irradiation, RNCIS NPs release NLG919 at tumor sites via photothermal properties, thereby promoting the recruitment of cytotoxic T lymphocytes and M1 polarization of macrophages, targeting the activation and amplification of immune responses. Herein, in vitro and in vivo studies showed that RNCIS NPs effectively kill cancer cells and eliminate primary and metastatic tumors. Therefore, this study suggests that semiconductor nanomaterials with narrow bandgaps have great potential as photoimmunotherapy agents and NIR light-responsive nanocarriers for controlled release, providing a great paradigm for synergetic tumor photoimmunotherapy. STATEMENT OF SIGNIFICANCE: The Erythrocyte membrane-coated, NLG919-loaded copper indium selenium (RNCIS) semiconductor was designed for eliminating primary and metastatic tumors. RNCIS exhibits chemodynamic, photodynamic, and photothermal activated immunotherapy by inhibiting indoleamine 2,3-dioxygenase-1. This can enhance the recruitment of cytotoxic T lymphocyte and M1 polarization of macrophage, leading to higher synergetic photo-immune therapeutic efficacy.

A Cholesterol Metabolic Regulated Hydrogen-Bonded Organic Framework (HOF)-Based Biotuner for Antibody Non-Dependent Immunotherapy Tailored for Glioblastoma

The metabolic reprogramming of glioblastoma (GBM) poses a tremendous obstacle to effective immunotherapy due to its impact on the immunosuppressive microenvironment. In this work, a hydrogen-bonded organic framework (HOF) specifically designed for GBM immunotherapy is developed, taking advantage of the relatively isolated cholesterol metabolism microenvironment in the central nervous system (CNS). The HOF-based biotuner regulates extra/intracellular cholesterol metabolism, effectively blocking the programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) pathway and reducing 2B4 expression. This metabolically disrupts the immunosuppressive microenvironment of GBM and rejuvenates CD8+ T cells. Moreover, cholesterol metabolism regulation offers additional benefits in treating GBM invasion. Furthermore, tumor microenvironment (TME)-initiated chemiexcited photodynamic therapy (PDT) is enhanced during the regulation of cholesterol metabolism, and the biotuner can effectively trigger immunogenic cell death (ICD) and increase the infiltration of cytotoxic T lymphocytes (CTLs) in GBM. By reversing the immunosuppressive microenvironment and bolstering chemiexcited-PDT, this approach invigorates efficient antibody non-dependent immunotherapy for GBM. This study provides a model for enhancing immunotherapy through cholesterol metabolism regulation and explores the feasibility of a "metabolic checkpoint" strategy in GBM treatment.

GM-CSF augmented the photothermal immunotherapeutic outcome of self-driving gold nanoparticles against a mouse CT-26 colon tumor model

BACKGROUND

Hypoxia is a frequent characteristic observed in solid tumors and is strongly associated with tumor metastasis, angiogenesis, and drug resistance. While the vasculature of hypoxic tumor tissues poses obstacles to the efficient administration of conventional drugs, it may prove advantageous in sustaining hyperthermia. Photothermal therapy (PTT) offers a promising treatment strategy that utilizes the activation of photosensitizers to produce heat, thus facilitating the selective ablation of tumor tissues.

METHOD

To enhance the accumulation of photothermal agents in tumor tissue and improve the effectiveness of PTT, we developed a self-propelled hybrid called Bif@PAu-NPs. This hybrid consists of polydopamine (PDA)-coated gold nanoparticles (Au-NPs) loaded onto the anaerobic Bifidobacterium infantis (Bif).

RESULTS

The Bif@PAu-NPs actively aggregated at the tumor site because the ability of Bif can target hypoxic regions, and PAu-NPs achieved precise PTT due to their high photothermal conversion efficiency (η = 67.8%). The tumor tissues were ablated by PTT, resulting in the release of antigens through immunogenic cell death (ICD), which stimulates an immune response. The inclusion of GM-CSF enhanced the immune response by recruiting dendritic cells and initiating long-term anti-tumor immunity.

CONCLUSION

The Bif@PAu-NPs hybrid effectively suppressed the growth of both primary tumors and re-challenged tumors. The utilization Bif@PAu-NPs in conjunction with GM-SCF exhibits great potential as a photothermal-immunotherapeutic strategy for precisely treating solid tumors. In this study, the bacterial Bif@PAu-NPs biohybrid is exploited the self-driving ability of anaerobic Bifidobacterium infantis to deliver polydopamine-modified gold nanoparticles to hypoxic region of tumor. Under irradiation with 808 nm NIR laser, the hybrid exerts precise photothermal therapy to stimulate the immune response, which is further enhanced by GM-CSF, leading to recruitment of dendritic cells and initiation of a long-term anti-tumor immunity remember to prevent tumor recurrence.

Cancer Immunotherapy Based on Cell Membrane-Coated Nanocomposites Augmenting cGAS/STING Activation by Efferocytosis Blockade

Innate immunity triggered by the cGAS/STING pathway has the potential to improve cancer immunotherapy. Previously, the authors reported that double-stranded DNA (dsDNA) released by dying tumor cells can trigger the cGAS/STING pathway. However, owing to efferocytosis, dying tumor cells are engulfed and cleared before the damaged dsDNA is released; hence, immunologic tolerance and immune escape occur. Herein, a cancer-cell-membrane biomimetic nanocomposites that exhibit tumor-immunotherapeutic effects are synthesized by augmenting the cGAS/STING pathway and suppressing efferocytosis. Once internalized by cancer cells, a combined chemo/chemodynamic therapy would be triggered, which damages their nuclear and mitochondrial DNA. Furthermore, the releasing Annexin A5 protein could inhibit efferocytosis effect and promote immunostimulatory secondary necrosis by preventing phosphatidylserine exposure, resulting in the burst release of dsDNA. These dsDNA fragments, as molecular patterns to immunogenic damage, escape from the cancer cells, activate the cGAS/STING pathway, enhance cross-presentation inside dendritic cells, and promote M1-polarization of tumor-associated macrophages. In vivo experiments suggest that the proposed nanocomposite could recruit cytotoxic T-cells and facilitate long-term immunological memory. Moreover, when combined with immune-checkpoint blockades, it could augment the immune response. Therefore, this novel biomimetic nanocomposite is a promising strategy for generating adaptive antitumor immune responses.

Nano-enabled colorectal cancer therapy

Colorectal cancer (CRC), one of the most common and deadliest diseases worldwide, poses a great health threat and social burden. The clinical treatments of CRC encompassing surgery, chemotherapy, and radiotherapy are challenged with toxicity, therapy resistance, and recurrence. In the past two decades, targeted therapy and immunotherapy have greatly improved the therapeutic benefits of CRC patients but they still suffer from drug resistance and low response rates. Very recently, gut microbiota regulation has exhibited a great potential in preventing and treating CRC, as well as in modulating the efficacy and toxicity of chemotherapy and immunotherapy. In this review, we provide a cutting-edge summary of nanomedicine-based treatment in colorectal cancer, highlighting the recent progress of oral and systemic tumor-targeting and/or tumor-activatable drug delivery systems as well as novel therapeutic strategies against CRC, including nano-sensitizing immunotherapy, anti-inflammation, gut microbiota modulation therapy, etc. Finally, the recent endeavors to address therapy resistance, metastasis, and recurrence in CRC were discussed. We hope this review could offer insight into the design and development of nanomedicines for CRC and beyond.

A Novel Strategy to Improve Tumor Targeting of Hydrophilic Drugs and Nanoparticles for Imaging Guided Synergetic Therapy

The fast renal clearance of hydrophilic small molecular anticancer drugs and ultrasmall nanoparticles (NPs) results in the low utilization rate and certain side effects, thus improving the tumor targeting is highly desired but faces great challenges. A novel and general β-cyclodextrin (CD) aggregation-induced assembly strategy to fabricate doxorubicin (DOX) and CD-coated NPs (such as Au) co-encapsulated pH-responsive nanocomposites (NCs) is proposed. By adding DOX×HCl and reducing pH in a reversed microemulsion system, hydrophilic CD-coated AuNPs rapidly assemble into large NCs. Then in situ polymerization of dopamine and sequentially coordinating with Cu2+ on the surface of NCs provide extra weak acid responsiveness, chemodynamic therapy (CDT), and improved biocompatibility as well as stability. The subsequent tumor microenvironment responsive dissociation notably improves their passive tumor targeting, bioavailability, imaging, and therapeutic capabilities, as well as facilitates their internalization by tumor cells and metabolic clearance, thereby reducing side effects. The combination of polymerized dopamine and assembled AuNPs reinforces photothermal capability, thus further boosting CDT through thermally amplifying Cu-catalyzed Fenton-like reaction. Both in vitro and in vivo studies confirm the desirable outcomes of these NCs as photoacoustic imaging guided trimodal (thermally enhanced CDT, photothermal therapy, and chemotherapy) synergistic tumor treatment agents with minimal systemic toxicity.

Research progress of calcium carbonate nanomaterials in cancer therapy: challenge and opportunity

Cancer has keeping the main threat to the health of human being. Its overall survival rate has shown rare substantial progress in spite of the improving diagnostic and treatment techniques for cancer in recent years. Indeed, such classic strategies for malignant tumor as surgery, radiation and chemotherapy have been developed and bring more hope to the patients, but still been accompanied by certain limitations, which include the challenge of managing large wound sizes, systemic toxic side effects, and harmful to the healthy tissues caused by imprecise alignment with tumors in radiotherapy. Furthermore, immunotherapy exhibits a limited therapeutic effect in advanced tumors which is reported only up to 25%-30%. The combination of nanomaterials and cancer treatment offers new hope for cancer patients, demonstrating strong potential in the field of medical research. Among the extensively utilized nanomaterials, calcium carbonate nanomaterials (CCNM) exhibit a broad spectrum of biomedical applications due to their abundant availability, cost-effectiveness, and exceptional safety profile. CCNM have the potential to elevate intracellular Ca2+ levels in tumor cells, trigger the mitochondrial damage and ultimately lead to tumor cell death. Moreover, compared with other types of nanomaterials, CCNM exhibit remarkable advantages as delivery systems owing to their high loading capacity, biocompatibility and biodegradability. The purpose of this review is to provide an overview of CCNM synthesis, focusing on summarizing its diverse roles in cancer treatment and the benefits and challenges associated with CCNM in cancer therapy. Hoping to present the significance of CCNM as for the clinical application, and summarize information for the design of CCNM and other types of nanomaterials in the future.

Albumin-based nanosystem for dual-modality imaging-guided chem-phototherapy against immune-cold triple-negative breast cancer

Triple-negative breast cancer is a highly aggressive and metastatic tumor; diagnosing it in the early stages is still difficult, and the prognosis for conventional radio-chemotherapy and immunotreatment is not promising due to cancer's immunosuppressive microenvironment. The utilization of protein-based nanosystem has proven to be effective in delivering agents with limited adverse effects, yet the combination of diagnosis and treatment remains a difficult challenge. This research took advantage of natural albumin and organic molecules to construct a self-assemble core-shell nanostructure combining with superparamagnetic iron oxide nanocrystals and heptamethine cyanine dye IR780 through non-covalent interactions. This nanocomposite successfully decreased the transverse relaxation time of the magnetic resonance hydrogen nucleus, resulting in outstanding T2 imaging, as well as emitting near-infrared II fluorescence, thereby the resulting dual-modality imaging tool was applied to improve diagnostic competency. It is noteworthy that the nanocomposites exhibited impressive enzyme-like catalytic and photothermal capabilities, resulting in a successful activation of the immune system to efficiently suppress distant metastatic lesions in vivo. Consequently, this nano-drug-based therapy could be an advantageous asset in reinforcing the immune system and hindering the growth and reappearance of the immune-cold breast cancer.

H2O2 Self-Supply and Glutathione Depletion Engineering Nanoassemblies for NIR-II Photoacoustic Imaging of Tumor Tissues and Photothermal-Enhanced Gas Starvation-Primed Chemodynamic Therapy

The development of tumor microenvironment (TME)-activated nanoassemblies which can produce a photoacoustic (PA) signal and enhance the H2O2 level is critical to achieve accurate diagnosis and highly efficient chemodynamic therapy (CDT). In this study, we developed nanoassemblies consisting of oxygen vacancy titanium dioxide (TiO2-x) surface-constructed copper, sulfur-doped mesoporous organosilica and glucose oxidase (TiO2-x@Cu,S-MONs@GOx, hereafter TMG). We found that highly abundant glutathione (GSH) in the TME nanoassemblies can reduce tetrasulfide bonds and Cu2+ to sulfur ions and Cu+ in the TMG nanoassemblies, respectively, causing the breakage of the tetrasulfide bond and the mesoporous structure collapse, releasing Cu+ ions and TiO2-x nanoparticles, and producing hydrogen sulfide gas, thereby achieving synergistic multimodal tumor treatment through TME-activated NIR-II PA imaging and photothermal-enhanced gas starvation-primed CDT. Therefore, the TMG nanoassemblies form a smart nanoplatform that can serve as an excellent tumor diagnosis-treatment agent by playing an important role in imaging-guided precision diagnosis of cancer and efficient targeting treatment.

A NIR-II Photoactivatable "ROS Bomb" with High-Density Cu2 O-Supported MoS2 Nanoflowers for Anticancer Therapy

The fast conversion of hydrogen peroxide (H2 O2 ) into reactive oxygen species (ROS) at tumor sites is a promising anticancer strategy by manipulating nanomedicines with near-infrared light in the second region (NIR-II). However, this strategy is greatly compromised by the powerful antioxidant capacity of tumors and the limited ROS generation rate of nanomedicines. This dilemma mainly stems from the lack of an effective synthesis method to support high-density copper-based nanocatalysts on the surface of photothermal nanomaterials. Herein, a multifunctional nanoplatform (MCPQZ) with high-density cuprous (Cu2 O) supported molybdenum disulfide (MoS2 ) nanoflowers (MC NFs) is developed for the efficient killing of tumors via a potent ROS storm by an innovative method. Under NIR-II light irradiation, the ROS intensity and maximum reaction velocity (Vmax ) produced by MC NFs are 21.6 and 33.8 times that of the non-irradiation group in vitro, which is much higher than most current nanomedicines. Moreover, the strong ROS storm in cancer cells is efficiently formed by MCPQZ (increased by 27.8 times compared to the control), thanks to the fact that MCPQZ effectively pre-weakens the multiple antioxidant systems of cancer cells. This work provides a novel insight to solve the bottleneck of ROS-based cancer therapy.

Destroying pathogen-tumor symbionts synergizing with catalytic therapy of colorectal cancer by biomimetic protein-supported single-atom nanozyme

The crucial role of intratumoral bacteria in the progression of cancer has been gradually recognized with the development of sequencing technology. Several intratumoral bacteria which have been identified as pathogens of cancer that induce progression, metastasis, and poor outcome of cancer, while tumor vascular networks and immunosuppressive microenvironment provide shelters for pathogens localization. Thus, the mutually-beneficial interplay between pathogens and tumors, named "pathogen-tumor symbionts", is probably a potential therapeutic site for tumor treatment. Herein, we proposed a destroying pathogen-tumor symbionts strategy that kills intratumoral pathogens, F. nucleatum, to break the symbiont and synergize to kill colorectal cancer (CRC) cells. This strategy was achieved by a groundbreaking protein-supported copper single-atom nanozyme (BSA-Cu SAN) which was inspired by the structures of native enzymes that are based on protein, with metal elements as the active center. BSA-Cu SAN can exert catalytic therapy by generating reactive oxygen species (ROS) and depleting GSH. The in vitro and in vivo experiments demonstrate that BSA-Cu SAN passively targets tumor sites and efficiently scavenges F. nucleatum in situ to destroy pathogen-tumor symbionts. As a result, ROS resistance of CRC through elevated autophagy mediated by F. nucleatum was relieved, contributing to apoptosis of cancer cells induced by intracellular redox imbalance generated by BSA-Cu SAN. Particularly, BSA-Cu SAN experiences renal clearance, avoiding long-term systemic toxicity. This work provides a feasible paradigm for destroying pathogen-tumor symbionts to block intratumoral pathogens interplay with CRC for antitumor therapy and an optimized trail for the SAN catalytic therapy by the clearable protein-supported SAN.

Cu-doped polypyrrole hydrogel with tumor catalyst activity for NIR-II thermo-radiotherapy

Introduction: Radiotherapy (RT) is one of the key methods for treating breast cancer. However, the effect of single RT is often poor because of insufficient deposition of X-rays in tumor sites and radiation resistance induced by the abnormal tumor microenvironment (overexpression of glutathione (GSH)). The development of multifunctional RT sensitizers and synergetic therapeutic strategies is, therefore, a promising area for enhancing the anticancer effect of RT. Methods: In this study, a multifunctional nanozyme hydrogel based on Cu-doped polypyrrole (CuP) was designed to work concertedly with a second near-infrared thermal RT. The CuP-based hydrogel (CH) reached the tumor site when injected in-situ and achieved long-term storage. Results: Once stimulated with 1064-nm laser irradiation, the heated and softened hydrogel system released CuP nanozyme to provide photothermal therapy, thereby inhibiting the repair of DNA damage caused by RT. In addition, CuP with dual nanozyme activity depleted the intracellular GSH to reduce the antioxidant capacity of the tumor. Moreover, CuP converted H₂O₂ to produce ·OH to directly kill the tumor cells, thus enhancing the capability of low-dose RT to inhibit tumor growth. In vivo experiments showed that the CH system used in combination with a low-power 1064-nm laser and low-dose RT (4 Gy) exhibited good synergistic anticancer effects and biological safety. Discussion: As a new light-responsive hydrogel system, CH holds immense potential for radio-sensitization.

Cuproptosis-related risk score predicts prognosis and characterizes the tumor microenvironment in colon adenocarcinoma

Introduction

Cuproptosis is a novel copper-dependent regulatory cell death (RCD), which is closely related to the occurrence and development of multiple cancers. However, the potential role of cuproptosis-related genes (CRGs) in the tumor microenvironment (TME) of colon adenocarcinoma (COAD) remains unclear.

Methods

Transcriptome, somatic mutation, somatic copy number alteration and the corresponding clinicopathological data of COAD were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus database (GEO). Difference, survival and correlation analyses were conducted to evaluate the characteristics of CRGs in COAD patients. Consensus unsupervised clustering analysis of CRGs expression profile was used to classify patients into different cuproptosis molecular and gene subtypes. TME characteristics of different molecular subtypes were investigated by using Gene set variation analysis (GSVA) and single sample gene set enrichment analysis (ssGSEA). Next, CRG Risk scoring system was constructed by applying logistic least absolute shrinkage and selection operator (LASSO) cox regression analysis and multivariate cox analysis. Real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC) were used to exam the expression of key Risk scoring genes.

Results

Our study indicated that CRGs had relatively common genetic and transcriptional variations in COAD tissues. We identified three cuproptosis molecular subtypes and three gene subtypes based on CRGs expression profile and prognostic differentially expressed genes (DEGs) expression profile, and found that changes in multilayer CRGs were closely related to the clinical characteristics, overall survival (OS), different signaling pathways, and immune cell infiltration of TME. CRG Risk scoring system was constructed according to the expression of 7 key cuproptosis-related risk genes (GLS, NOX1, HOXC6, TNNT1, GLS, HOXC6 and PLA2G12B). RT-qPCR and IHC indicated that the expression of GLS, NOX1, HOXC6, TNNT1 and PLA2G12B were up-regulated in tumor tissues, compared with those in normal tissues, and all of GLS, HOXC6, NOX1 and PLA2G12B were closely related with patient survival. In addition, high CRG risk scores were significantly associated with high microsatellite instability (MSI-H), tumor mutation burden (TMB), cancer stem cell (CSC) indices, stromal and immune scores in TME, drug susceptibility, as well as patient survival. Finally, a highly accurate nomogram was constructed to promote the clinical application of the CRG Risk scoring system.

Discussion

Our comprehensive analysis showed that CRGs were greatly associated with TME, clinicopathological characteristics, and prognosis of patient with COAD. These findings may promote our understanding of CRGs in COAD, providing new insights for physicians to predict prognosis and develop more precise and individualized therapy strategies.

A dual-function probe with aggregation-induced emission feature for Cu2+ detection and chemodynamic therapy

Herein, a fluorescent probe (named TPACP) with aggregation-induced emission (AIE) feature was developed and utilized for the selective detection of Cu²⁺ with high sensitivity and fast-response. The resultant TPACP@Cu²⁺ complexes from coordination of TPACP with Cu²⁺ can also be potentially applied for chemodynamic and photodynamic therapy.

The CD47-SIRPα axis is a promising target for cancer immunotherapies

Cluster of differentiation 47(CD47) is a transmembrane protein that is ubiquitously found on the surface of many cells in the body and uniquely overexpressed by both solid and hematologic malignant cells. CD47 interacts with signal-regulatory protein α (SIRPα), to trigger a "don't eat me" signal and thereby achieve cancer immune escape by inhibiting macrophage-mediated phagocytosis. Thus, blocking the CD47-SIRPα phagocytosis checkpoint, for release of the innate immune system, is a current research focus. Indeed, targeting the CD47-SIRPα axis as a cancer immunotherapy has shown promising efficacies in pre-clinical outcomes. Here, we first reviewed the origin, structure, and function of the CD47-SIRPα axis. Then, we reviewed its role as a target for cancer immunotherapies, as well as the factors regulating CD47-SIRPα axis-based immunotherapies. We specifically focused on the mechanism and progress of CD47-SIRPα axis-based immunotherapies and their combination with other treatment strategies. Finally, we discussed the challenges and directions for future research and identified potential CD47-SIRPα axis-based therapies that are suitable for clinical application.

Activatable Immunoprotease Nanorestimulator for Second Near-Infrared Photothermal Immunotherapy of Cancer

Photothermal immunotherapy is a combinational cancer therapy modality, wherein the photothermal process can noninvasively ablate cancer and efficiently trigger cancer immunogenic cell death to ignite antitumor immunity. However, cancer cells can resist the cytotoxic lymphocyte-mediated antitumor effect via expressing serine protease inhibitory proteins (serpins) to deactivate proteolytic immunoproteases. Herein, we report a smart polymer nanoagonist (SPND) with second near-infrared (NIR-II) phototherapeutic ablation and tumor-specific immunoprotease granzyme B (GrB) restimulation for cancer photothermal immunotherapy. SPND has a semiconducting polymer backbone grafted with a small-molecule inhibitor of serpinB9 (Sb9i) via a glutathione (GSH)-cleavable linker. Once in the tumor, Sb9i can be specifically liberated from SPND to inhibit serpinB9, restimulating the activity of GrB to enhance cancer immunotherapy. Moreover, SPND induces photothermal therapy for direct tumor ablation and immunogenic cancer cell death (ICD) under NIR-II photoirradiation. Therefore, such a smart nanoagonist represents a way toward combination photothermal immunotherapy (PTI).

Design of Disintegrable Nanoassemblies to Release Multiple Small-Sized Nanoparticles

The therapeutic and diagnostic effects of nanoparticles depend on the efficiency of their delivery to targeted tissues, such as tumors. The size of nanoparticles, among other characteristics, plays a crucial role in determining their tissue penetration and retention. Small nanoparticles may penetrate deeper into tumor parenchyma but are poorly retained, whereas large ones are distributed around tumor blood vessels. Thus, compared to smaller individual nanoparticles, assemblies of such nanoparticles due to their larger size are favorable for prolonged blood circulation and enhanced tumor accumulation. Upon reaching the targeted tissues, nanoassemblies may dissociate at the target region and release the smaller nanoparticles, which is beneficial for their distribution at the target site and ultimate clearance. The recent emerging strategy that combines small nanoparticles into larger, biodegradable nanoassemblies has been demonstrated by several groups. This review summarizes a variety of chemical and structural designs for constructing stimuli-responsive disintegrable nanoassemblies as well as their different disassembly routes. These nanoassemblies have been applied as demonstrators in the fields of cancer therapy, antibacterial infection, ischemic stroke recovery, bioimaging, and diagnostics. Finally, we summarize stimuli-responsive mechanisms and their corresponding nanomedicine designing strategies, and discuss potential challenges and barriers towards clinical translation.

Tumor microenvironment remodeling via targeted depletion of M2-like tumor-associated macrophages for cancer immunotherapy

M2-like tumor-associated macrophages (TAMs) typically exhibit numerous tumor-promoting properties. Reducing the abundance of M2-like TAMs would shed light on the relief of immunosuppressive tumor microenvironment (TME), activation of the host immune system, infiltration of CD8⁺ T cells into the TME and restoring the function of the infiltrating T cells, which collectively inhibits tumor growth. Therefore, targeted depletion of M2-like TAMs can be a promising immunotherapy approach. In this study, we rationally constructed an M2-like TAMs-targeted nanoliposome, which encapsulates zoledronic acid (ZA) in the core, loads hematoporphyrin monomethyl ether (HMME, a typical sonosensitizer) in the lipid bilayer, and modifies M2pep peptide (the targeting unit) on the surface (designated as M-H@lip-ZA). Our aim is to validate the effectiveness of M-H@lip-ZA nanoliposomes to remodel TME via targeted depletion of M2-like TAMs for cancer immunotherapy. Through the M2pep peptide, M-H@lip-ZA can be efficiently delivered to M2-like TAMs. In the meantime, reactive oxygen species (ROS) resulting from sonodynamic therapy (SDT), together with inner ZA that shows high affinity and cytotoxicity to TAMs, can effectively deplete M2-like TAMs and remodel TME (normalize tumor vasculatures, strengthen intertumoral perfusion, ease tumor hypoxia, increase immune-promoting cytokines and decrease immunosuppressive cytokines). The tumor growth can be effectively inhibited. This work proposed a new paradigm for cancer immunotherapy via targeted depletion of M2-like TAMs. STATEMENT OF SIGNIFICANCE: • M2-like TAMs-targeted nanoliposome (M-H@lip-ZA) was designed and prepared. • Sonodynamic therapy (SDT), together with zoledronic acid (ZA) that shows high affinity and cytotoxicity to tumor-associated macrophages (TAMs), can effectively deplete M2-like TAMs. Subsequently, immune-promoting tumor microenvironment (TME) can be formed, which includes normalized tumor vasculatures, enhanced intertumoral perfusion, relieved tumor hypoxia, increased immune-promoting cytokines, and decreased immunosuppressive cytokines. • The targeted depletion of M2-like TAMs is a promising cancer immunotherapy approach.

Tirapazamine-loaded UiO-66/Cu for ultrasound-mediated promotion of chemodynamic therapy cascade hypoxia-activated anticancer therapy

Chemodynamic therapy (CDT), an emerging oncology treatment, has received considerable attention owing to its high selectivity, less aggressiveness, and endogenous stimulation. However, the complex intra-tumor environment limits the therapeutic effect. In this study, Cu⁺ was directly doped into the structure of the UiO-66 matrix using an in situ one-pot oil bath method. The as-formed UiO-66/Cu possessed a large surface area, making it feasible to modify folic acid (FA) and carry more chemotherapeutic agents like tirapazamine (TPZ), thus forming UiO-66/Cu-FA-TPZ nanoplatforms. For CDT, the nanoplatform catalyzed the cyclic generation of the highly oxidizing hydroxyl radical (·OH) from H₂O₂. Particularly, low-frequency ultrasound enhanced the curative effect. Notably, in a tumor, a severe hypoxic environment and ultrasound can activate more TPZ for safe and efficient chemotherapy, achieving synergistic and hypoxia-activated tumor treatment with a low risk of side effects. Moreover, the nanoplatform exhibits computed tomography imaging functions for combined diagnosis and treatment. Our designed nanoplatform overcomes the dilemma of insufficient efficacy from conventional therapy attributed to a hypoxic environment, expecting to guide the design of future treatment regimens for hypoxic tumors.

A Physiologically Responsive Nanocomposite Hydrogel for Treatment of Head and Neck Squamous Cell Carcinoma via Proteolysis-Targeting Chimeras Enhanced Immunotherapy

Although immunotherapy has revolutionized oncotherapy, only ≈15% of head and neck squamous cell carcinoma (HNSCC) patients benefit from the current therapies. An immunosuppressive tumor microenvironment (TME) and dysregulation of the polycomb ring finger oncogene BMI1 are potential reasons for the failure. Herein, to promote immunotherapeutic efficacy against HNSCC, an injectable nanocomposite hydrogel is developed with a polymer framework (PLGA-PEG-PLGA) that is loaded with both imiquimod encapsulated CaCO₃ nanoparticles (RC) and cancer cell membrane (CCM)-coated mesoporous silica nanoparticles containing a peptide-based proteolysis-targeting chimeras (PROTAC) for BMI1 and paclitaxel (PepM@PacC). Upon injection, this nanocomposite hydrogel undergoes in situ gelation, after which it degrades in the TME over time, releasing RC and PepM@PacC nanoparticles to respectively perform immunotherapy and chemotherapy. Specifically, the RC particles selectively manipulate tumor-associated macrophages and dendritic cells to activate a T-cell immune response, while CCM-mediated homologous targeting and endocytosis delivers the PepM@PacC particles into cancer cells, where endogenous glutathione promotes disulfide bond cleavage to release the PROTAC peptide for BMI1 degradation and frees the paclitaxel from the particle pores to elicit apoptosis meanwhile enhance immunotherapy. Thus, the nanocomposite hydrogel, which is designed to exploit multiple known vulnerabilities of HNSCC, succeeds in suppressing both growth and metastasis of HNSCC.

Colon-targeted bacterial hydrogel for tumor vascular normalization and improved chemotherapy

The endogenous H₂S plays an important role in the occurrence and development of colon cancer, and is related to the abnormal blood vessels. Here, we reported on a sulfhydryl hyaluronid-based hydrogel (HA-SH) synthesized by amide reaction and further obtained a bacterial hydrogel by loading Thiobacillus denitrificans to the hydrogel for targeting adhesion to the colon. It was found that the loaded bacteria in HA-SH hydrogel can scavenge excess H₂S in colon cancer, then promote tumor vascular normalization and improve the delivery of chemotherapy drug CPT to inhibit tumor progression. Both in vivo and in vitro experiments show that the self-crosslinked bacterial hydrogel has satisfactory effects in inhibiting tumor progression and promoting tumor vascular normalization in colon cancer. This study presents an efficient method to target the colon and consume overexpressed H₂S in colon cancer to inhabit tumor progression, providing a new way for oral drug treatment of colon cancer.

Thermal immuno-nanomedicine in cancer

Immunotherapy has revolutionized the treatment of patients with cancer. However, promoting antitumour immunity in patients with tumours that are resistant to these therapies remains a challenge. Thermal therapies provide a promising immune-adjuvant strategy for use with immunotherapy, mostly owing to the capacity to reprogramme the tumour microenvironment through induction of immunogenic cell death, which also promotes the recruitment of endogenous immune cells. Thus, thermal immunotherapeutic strategies for various cancers are an area of considerable research interest. In this Review, we describe the role of the various thermal therapies and provide an update on attempts to combine these with immunotherapies in clinical trials. We also provide an overview of the preclinical development of various thermal immuno-nanomedicines, which are capable of combining thermal therapies with various immunotherapy strategies in a single therapeutic platform. Finally, we discuss the challenges associated with the clinical translation of thermal immuno-nanomedicines and emphasize the importance of multidisciplinary and inter-professional collaboration to facilitate the optimal translation of this technology from bench to bedside.

Piezocatalytic Medicine: An Emerging Frontier using Piezoelectric Materials for Biomedical Applications

Emerging piezocatalysts have demonstrated their remarkable application potential in diverse medical fields. In addition to their ultrahigh catalytic activities, their inherent and unique charge-carrier-releasing properties can be used to initiate various redox catalytic reactions, displaying bright prospects for future medical applications. Triggered by mechanical energy, piezocatalytic materials can release electrons/holes, catalyze redox reactions of substrates, or intervene in biological processes to promote the production of effector molecules for medical purposes, such as decontamination, sterilization, and therapy. Such a medical application of piezocatalysis is termed as piezocatalytic medicine (PCM) herein. To pioneer novel medical technologies, especially therapeutic modalities, this review provides an overview of the state-of-the-art research progress in piezocatalytic medicine. First, the principle of piezocatalysis and the preparation methodologies of piezoelectric materials are introduced. Then, a comprehensive summary of the medical applications of piezocatalytic materials in tumor treatment, antisepsis, organic degradation, tissue repair and regeneration, and biosensing is provided. Finally, the main challenges and future perspectives in piezocatalytic medicine are discussed and proposed, expecting to fuel the development of this emerging scientific discipline.

Implications of hydrogen sulfide in colorectal cancer: Mechanistic insights and diagnostic and therapeutic strategies

Hydrogen sulfide (H₂S) is an important signaling molecule in colorectal cancer (CRC). It is produced in the colon by the catalytic synthesis of the colonocytes' enzymatic systems and the release of intestinal microbes, and is oxidatively metabolized in the colonocytes' mitochondria. Both endogenous H₂S in colonic epithelial cells and exogenous H₂S in intestinal lumen contribute to the onset and progression of CRC. The up-regulation of endogenous synthetases is thought to be the cause of the elevated H₂S levels in CRC cells. Different diagnostic probes and combination therapies, as well as tumor treatment approaches through H₂S modulation, have been developed in recent years and have become active area of investigation for the diagnosis and treatment of CRC. In this review, we focus on the specific mechanisms of H₂S production and oxidative metabolism as well as the function of H₂S in the occurrence, progression, diagnosis, and treatment of CRC. We also discuss the present challenges and provide insights into the future research of this burgeoning field.

Cold Nanozyme for Precise Enzymatic Antitumor Immunity

Precise catalysis is pursued for the biomedical applications of artificial enzymes. It is feasible to precisely control the catalysis of artificial enzymes via tunning the temperature-dependent enzymatic kinetics. The safety window of cold temperatures (4-37 °C) for the human body is much wider than that of thermal temperatures (37-42 °C). Although the development of cold-activated artificial enzymes is promising, there is currently a lack of suitable candidates. Herein, a cold-activated artificial enzyme is presented with Bi₂Fe₄O₉ nanosheets (NSs) as a paradigm. The as-obtained Bi₂Fe₄O₉ NSs possess glutathione oxidase (GSHOx)-like activity under cold temperature due to their pyroelectricity. Bi₂Fe₄O₉ NSs trigger the cold-enzymatic death of tumor cells via apoptosis and ferroptosis, and minimize the off-target toxicity to normal tissues. Moreover, an interventional device is fabricated to intelligently and remotely control the enzymatic activity of Bi₂Fe₄O₉ NSs on a smartphone. With Bi₂Fe₄O₉ NSs as an in situ vaccine, systemic antitumor immunity is successfully activated to suppress tumor metastasis and relapse. Moreover, blood biochemistry analysis and histological examination indicate the high biosafety of Bi₂Fe₄O₉ NSs for in vivo applications. This cold nanozyme provides a strategy for cancer vaccines, which can benefit the precise control over catalytic nanomedicines.