Diversified strategies based on nanoscale metal-organic frameworks for cancer therapy: The leap from monofunctional to versatile

Biodegradable nano-immune agonist for enhanced immunotherapy of melanoma via the synergistic action of cuproptosis and cGAS-STING enhanced immune response

Immunotherapy has emerged as a promising approach for melanoma treatment. However, the efficacy of traditional immune checkpoint inhibitors (ICIs) remains limited due to the immunosuppressive tumor microenvironment. In this study, a novel nano-immune agonist, pLCGM-OVA, was developed to induce cuproptosis and activate the cGAS-STING pathway, thereby enhancing melanoma immunotherapy. The pLCGM-OVA was synthesized by conjugating PDGFB with liposomes that encapsulate CuGdMn nanoclusters (CGM) and ovalbumin (OVA). Upon exposure to the acidic microenvironment of tumours, pLCGM-OVA undergoes degradation, releasing Cu ions, Mn ions, and free OVA. This release triggers reactive oxygen species-mediated cuproptosis and activates the cGAS-STING pathway via Mn, leading to the subsequent induction of immunogenic cell death (ICD). Simultaneously, free OVA and ICD antigens are presented to dendritic cells (DCs), promoting their maturation and enhancing cytotoxic T lymphocyte infiltration, thus improving the efficacy of tumour immunotherapy. In vitro and in vivo studies demonstrated that pLCGM-OVA significantly inhibited tumour growth and recurrence with minimal systemic toxicity, owing to the combined effects of cuproptosis and immunotherapy. Moreover, pLCGM-OVA exhibited excellent T1 contrast (9.26 mM-1s-1), significantly enhancing T1-weighted magnetic resonance imaging signals of tumours, facilitating accurate melanoma diagnosis. Overall, this work presents a highly promising candidate for the development of potent immune agonists for melanoma treatment.

A Highly Biocompatible Polyoxotungstate with Fenton-like Reaction Activity for Potent Chemodynamic Therapy of Tumors

Integrating Fenton chemistry and nanomedicine into cancer therapy has significantly promoted the development of chemodynamic therapy (CDT). Nanoscale polyoxometalates (POMs), with their reversible redox properties, exhibit promising potential in developing outstanding CDT drugs by exploring their Fenton-like catalytic reactivity in tumor environments. However, such research is still in its infancy due to the challenges of acquiring POMs that are both easily prepared and possess ideal therapeutic effects, physiological solubility, biocompatibility and safety. In this work, we report the synthesis of a new crystalline antimonotungstate {Dy2Sb2W7O23(OH)(DMF)2(SbW9O33)2} (1, DMF=N, N-dimethylformamide) with gram-scale high yield via a facile "one-pot" solvothermal reaction. 1 exhibits not only a soluble and water-stable POM nanocluster, but also excellent catalytic activity for hydroxyl radical-generating Fenton-like reactions. Further biomedical studies reveal that 1 can trigger cell apoptosis and promote lipid peroxidation, exhibiting high cytotoxicity and selectivity towards B16-F10 mouse melanoma cancer cells with an IC50 value of 4.75 μM. Especially, 1 can inhibit melanoma growth in vivo with favorable biosafety, achieving a 5.2-fold reduction in tumor volume and a weight loss of 76.0 % at the dose of 70 μg/kg. This research not only demonstrates the immense potential of antimonotungstates in CDT drug development for the first time but also provides new insights and directions for the development of novel anticancer drugs.

Immunoadjuvant-functionalized metal-organic frameworks: synthesis and applications in tumor immune modulation

Cancer immunotherapy, which leverages the body's immune system to recognize and attack cancer cells, has made significant progress, particularly in the treatment of metastatic tumors. However, challenges such as drug stability and off-target effects still limit its clinical success. To address these issues, metal-organic frameworks (MOFs) have emerged as promising nanocarriers in cancer immunotherapy. MOFs have unique porous structure, excellent drug loading capacity, and tunable surface modification properties. MOFs not only enhance drug delivery efficiency but also allow for precise control of drug release. They reduce off-target effects and significantly improve targeting and therapy efficacy. As research deepens, MOFs' effectiveness as drug carriers has been refined. When combined with immunoadjuvants or anticancer drugs, MOFs further stimulate the immune response. This improves the specificity of immune attacks on tumors. This review provides a comprehensive overview of the applications of MOFs in cancer immunotherapy. It focuses on synthesis, drug loading strategies, and surface modifications. It also analyzes their role in enhancing immunotherapy effectiveness. By integrating current research, we aim to provide insights for the future development of immunoadjuvant-functionalized MOFs, accelerating their clinical application for safer and more effective cancer treatments.

Inhalable Metal-Organic Frameworks: A Promising Delivery Platform for Pulmonary Diseases Treatment

Inhalation delivery, offering a direct pathway for administering drugs to the lungs in the form of dry powders or aerosols, stands out as an optimal approach for the localized treatment of pulmonary diseases. However, the intricate anatomical architecture of the lung often poses challenges in maintaining effective drug concentrations within the lungs over extended periods. This highlights the pressing need to develop rational inhalable drug delivery systems that can improve treatment outcomes for respiratory diseases. Metal-organic frameworks (MOFs) assembled from inorganic metal ions and organic ligands, characterized by customizable porous architecture and chemical composition, modifiable porosity, vast surface area, straightforward surface modification, and adjustable biocompatibility, have garnered extensive attention in the biomedical sphere. The introduction of MOFs into inhalation therapy represents a promising avenue to navigate past the hurdles associated with traditional inhalation methods. Therefore, this review summarizes the characteristics of inhalation delivery together with the latest advances, challenges, and opportunities in utilizing inhalable MOFs for treating lung diseases and discusses prospects in this field alongside the potential pathways for translating this strategy into clinic.

Metal-organic frameworks as nanoplatforms for combination therapy in cancer treatment

The integration of nanotechnology into cancer treatment has revolutionized chemotherapy, boosted its effectiveness while reduced side effects. Among the various nanotherapeutic approaches, metal-organic frameworks (MOFs) stand out as promising carriers for targeted chemotherapy, with the added benefit of enabling combination therapies. MOFs, composed of metal ions or clusters linked by coordination bonds, tackle critical issues in traditional cancer treatments, such as poor stability, limited efficacy, and severe side effects. Their key advantages include customizable size and shape, diverse compositions, controlled porosity, large surface areas, ease of modification, and biocompatibility. This review highlights recent advancements in the use of MOFs for cancer therapy, showcasing their role in both monotherapies and combination strategies. Additionally, it explores the future potential and challenges of MOF-based platforms in tumor treatment.

Metal-organic frameworks as candidates for tumor sonodynamic therapy: Designable structures for targeted multifunctional transformation

Sonodynamic therapy (SDT), utilizing ultrasound (US) as the trigger, has gained popularity recently as a therapeutic approach with significant potential for treating various diseases. Metal-organic frameworks (MOFs), characterized by structural flexibility, are prominently emerging in the SDT realm as an innovative type of sonosensitizer, offering functional tunability and biocompatibility. However, due to the inherent limitations of MOFs, such as low reactivity to reactive oxygen species and challenges posed by the complex tumor microenvironment, MOF-based sonosensitizers with singular functions are unable to demonstrate the desired therapeutic efficacy and may pose risks of toxicity, limiting their biological applications to superficial tissues. MOFs generally possess distinctive crystalline structures and properties, and their controlled coordination environments provide a flexible platform for exploring structure-effect relationships and guiding the design and development of MOF-based nanomaterials to unlock their broader potential in biological fields. The primary focus of this paper is to summarize cases involving the modification of different MOF materials and the innovative strategies developed for various complex conditions. The paper outlines the diverse application areas of functionalized MOF-based sonosensitizers in tumor synergistic therapies, highlighting the extensive prospects of SDT. Additionally, challenges confronting SDT are briefly summarized to stimulate increased scientific interest in the practical application of MOFs and the successful clinical translation of SDT. Through these discussions, we strive to foster advancements that lead to early-stage clinical benefits for patients. STATEMENT OF SIGNIFICANCE: 1. An overview for the progresses in SDT explored from a novel and fundamental perspective. 2. Different modification strategies to improve the MOFs-mediated SDT efficacy are provided. 3. Guidelines for the design of multifunctional MOFs-based sonosensitizers are offered. 4. Powerful tumor ablation potential is reflected in SDT-led synergistic therapies. 5. Future challenges in the field of MOFs-based SDT in clinical translation are suggested.

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.

Current status of Fe-based MOFs in biomedical applications

Recently nanoparticle-based platforms have gained interest as drug delivery systems and diagnostic agents, especially in cancer therapy. With their ability to provide preferential accumulation at target sites, nanocarrier-constructed antitumor drugs can improve therapeutic efficiency and bioavailability. In contrast, metal-organic frameworks (MOFs) have received increasing academic interest as an outstanding class of coordination polymers that combine porous structures with high drug loading via temperature modulation and ligand interactions, overcoming the drawbacks of conventional drug carriers. FeIII-based MOFs are one of many with high biocompatibility and good drug loading capacity, as well as unique Fenton reactivity and superparamagnetism, making them highly promising in chemodynamic and photothermal therapy, and magnetic resonance imaging. Given this, this article summarizes the applications of FeIII-based MOFs in three significant fields: chemodynamic therapy, photothermal therapy and MRI, suggesting a logical route to new strategies. This article concludes by summarising the primary challenges and development prospects in these promising research areas.

Strategies to engineer various nanocarrier-based hybrid catalysts for enhanced chemodynamic cancer therapy

Chemodynamic therapy (CDT) is a newly developed cancer-therapeutic modality that kills cancer cells by the highly toxic hydroxyl radical (˙OH) generated from the in situ triggered Fenton/Fenton-like reactions in an acidic and H2O2-overproduced tumor microenvironment (TME). By taking the advantage of the TME-activated catalytic reaction, CDT enables a highly specific and minimally-invasive cancer treatment without external energy input, whose efficiency mainly depends on the reactant concentrations of both the catalytic ions and H2O2, and the reaction conditions (including pH, temperature, and amount of glutathione). Unfortunately, it suffers from unsatisfactory therapy efficiency for clinical application because of the limited activators (i.e., mild acid pH and insufficient H2O2 content) and overexpressed reducing substance in TME. Currently, various synergistic strategies have been elaborately developed to increase the CDT efficiency by regulating the TME, enhancing the catalytic efficiency of catalysts, or combining with other therapeutic modalities. To realize these strategies, the construction of diverse nanocarriers to deliver Fenton catalysts and cooperatively therapeutic agents to tumors is the key prerequisite, which is now being studied but has not been thoroughly summarized. In particular, nanocarriers that can not only serve as carriers but are also active themselves for therapy are recently attracting increasing attention because of their less risk of toxicity and metabolic burden compared to nanocarriers without therapeutic capabilities. These therapy-active nanocarriers well meet the requirements of an ideal therapy system with maximum multifunctionality but minimal components. From this new perspective, in this review, we comprehensively summarize the very recent research progress on nanocarrier-based systems for enhanced CDT and the strategies of how to integrate various Fenton agents into the nanocarriers, with particular focus on the studies of therapy-active nanocarriers for the construction of CDT catalysts, aiming to guide the design of nanosystems with less components and more functionalities for enhanced CDT. Finally, the challenges and prospects of such a burgeoning cancer-theranostic modality are outlooked to provide inspirations for the further development and clinical translation of CDT.

Aptamer modified Zr-based porphyrinic nanoscale metal-organic frameworks for active-targeted chemo-photodynamic therapy of tumors

Active-targeted nanoplatforms could specifically target tumors compared to normal cells, making them a promising therapeutic agent. The aptamer is a kind of short DNA or RNA sequence that can specifically bind to target molecules, and could be widely used as the active targeting agents of nanoplatforms to achieve active-targeted therapy of tumors. Herein, an aptamer modified nanoplatform DOX@PCN@Apt-M was designed for active-targeted chemo-photodynamic therapy of tumors. Zr-based porphyrinic nanoscale metal organic framework PCN-224 was synthesized through a one-pot reaction, which could produce cytotoxic 1O2 for efficient treatment of tumor cells. To improve the therapeutic effect of the tumor, the anticancer drug doxorubicin (DOX) was loaded into PCN-224 to form DOX@PCN-224 for tumor combination therapy. Active-targeted combination therapy achieved by modifying the MUC1 aptamer (Apt-M) onto DOX@PCN-224 surface can not only further reduce the dosage of therapeutic agents, but also reduce their toxic and side effects on normal tissues. In vitro, experimental results indicated that DOX@PCN@Apt-M exhibited enhanced combined therapeutic effect and active targeting efficiency under 808 nm laser irradiation for MCF-7 tumor cells. Based on PCN-224 nanocarriers and aptamer MUC1, this work provides a novel strategy for precisely targeting MCF-7 tumor cells.

Recent Progress in Carrier-Free Nanomedicine for Tumor Phototherapy

Safe and effective strategies are urgently needed to fight against the life-threatening diseases of various cancers. However, traditional therapeutic modalities, such as radiotherapy, chemotherapy and surgery, exhibit suboptimal efficacy for malignant tumors owing to the serious side effects, drug resistance and even relapse. Phototherapies, including photodynamic therapy (PDT) and photothermal therapy (PTT), are emerging therapeutic strategies for localized tumor inhibition, which can produce a large amount of reactive oxygen species (ROS) or elevate the temperature to initiate cell death by non-invasive irradiation. In consideration of the poor bioavailability of phototherapy agents (PTAs), lots of drug delivery systems have been developed to enhance the tumor targeted delivery. Nevertheless, the carriers of drug delivery systems inevitably bring biosafety concerns on account of their metabolism, degradation, and accumulation. Of note, carrier-free nanomedicine attracts great attention for clinical translation with synergistic antitumor effect, which is characterized by high drug loading, simplified synthetic method and good biocompatibility. In this review, the latest advances of phototherapy with various carrier-free nanomedicines are summarized, which may provide a new paradigm for the future development of nanomedicine and tumor precision therapy.

Hybrid Nanomaterials for Cancer Immunotherapy

Nano-immunotherapy has been recognized as a highly promising strategy for cancer treatment in recent decades, which combines nanotechnology and immunotherapy to combat against tumors. Hybrid nanomaterials consisting of at least two constituents with distinct compositions and properties, usually organic and inorganic, have been engineered with integrated functions and enormous potential in boosting cancer immunotherapy. This review provides a summary of hybrid nanomaterials reported for cancer immunotherapy, including nanoscale metal-organic frameworks, metal-phenolic networks, mesoporous organosilica nanoparticles, metallofullerene nanomaterials, polymer-lipid, and biomacromolecule-based hybrid nanomaterials. The combination of immunotherapy with chemotherapy, chemodynamic therapy, radiotherapy, radiodynamic therapy, photothermal therapy, photodynamic therapy, and sonodynamic therapy based on hybrid nanomaterials is also discussed. Finally, the current challenges and the prospects for designing hybrid nanomaterials and their application in cancer immunotherapy are outlined.

Fe/Mn Bimetal-Doped ZIF-8-Coated Luminescent Nanoparticles with Up/Downconversion Dual-Mode Emission for Tumor Self-Enhanced NIR-II Imaging and Catalytic Therapy

ZIF-8, as an important photoresponsive metal-organic framework (MOF), holds great promise in the field of cancer theranostics owing to its versatile physiochemical properties. However, its photocatalytic anticancer application is still restricted because of the wide bandgap and specific response to ultraviolet light. Herein, we developed lanthanide-doped nanoparticles (LDNPs) coated with Fe/Mn bimetal-doped ZIF-8 (LDNPs@Fe/Mn-ZIF-8) for second near-infrared (NIR-II) imaging-guided synergistic photodynamic/chemodynamic therapy (PDT/CDT). The LDNPs were synthesized by encapsulating an optimal Yb³⁺/Ce³⁺-doped active shell on the NaErF₄:Tm core to achieve dual-mode red upconversion (UC) and NIR-II downconversion (DC) emission upon NIR laser irradiation. At the optimal doping concentration, the UC and DC NIR-II emission intensities of LDNPs were increased 30.2- and 13.2-fold above those of core nanoparticles, which endowed LDNPs@Fe/Mn-ZIF-8 with an outstanding capability to carry out UC-mediated PDT and NIR-II optical imaging. In addition, the dual doping of Fe²⁺/Mn²⁺ markedly decreased the bandgap of the ZIF-8 photosensitizer from 5.1 to 1.7 eV, expanding the excitation threshold of ZIF-8 to the visible light region (∼650 nm), which enabled Fe/Mn-ZIF-8 to be efficiently excited by UC photons to achieve photocatalytic-driven PDT. Furthermore, Fe²⁺/Mn²⁺ ions could be responsively released in the tumor microenvironment through degradation of Fe/Mn-ZIF-8, thereby producing hydroxyl radicals (·OH) by Fenton/Fenton-like reactions to realize CDT. Meanwhile, the degradation of Fe/Mn-ZIF-8 endowed the nanosystems with tumor self-enhanced NIR-II imaging function, providing precise guidance for CDT/PDT.

Nanoscale MOFs: From synthesis to drug delivery and theranostics applications

Since the first report in 1989, Metal-Organic Frameworks (MOFs) self-assembled from metal ions or clusters, as well as organic linkers, have attracted extensive attention. Due to their flexible composition, large surface areas, modifiable surface properties, and their degradability, there has been an exponential increase in the study of MOFs materials, specifically in drug delivery system areas such as infection, diabetes, pulmonary disease, ocular disease, imaging, tumor therapy, and especially cancer theranostics. In this review, we discuss the trends in MOFs biosafety, from "green" synthesis to applications in drug delivery systems. Firstly, we present the different "green" synthesis approaches used to prepare MOFs materials. Secondly, we detail the methods for the functional coating, either through grafting targeting units, poly(ethylene glycol) (PEG) chains or by using cell membranes. Then, we discuss drug encapsulation strategies, host-guest interactions, as well as drug release mechanisms. Lastly, we report on the drug delivery applications of nanoscale MOFs. In particular, we discuss MOFs-based imaging techniques, including magnetic resonance imaging (MRI), photoacoustic imaging (PAI), positron emission tomography (PET), and fluorescence imaging. MOFs-based cancer therapy methods are also presented, such as photothermal therapy (PTT), photodynamic therapy (PDT), radiotherapy (RT), chemotherapy, and immunotherapy.

Recent advances in porous MOFs and their hybrids for photothermal cancer therapy

Cancer is still one of the most life-threatening diseases in the world. Among the various cancer therapeutic strategies, photothermal therapy (PTT) has attracted considerable attention due to its high treatment efficacy, low invasive burden, and minor side effects. Microporous metal-organic frameworks (MOFs) are potential materials for photothermal tumor treatment thanks to their high surface areas, suitable pore geometry, and easy functionalization. Through designating organic linkers, encapsulating PTT agents and fabricating MOF hybrids, MOF-based treatment platforms have great potential in PTT. In this review, we mainly summarize the recent advances of MOFs in photothermal combined cancer therapy. The present challenges and possible future prospects in this field are also explored.

Development of Anticancer Peptides Using Artificial Intelligence and Combinational Therapy for Cancer Therapeutics

Cancer is a group of diseases causing abnormal cell growth, altering the genome, and invading or spreading to other parts of the body. Among therapeutic peptide drugs, anticancer peptides (ACPs) have been considered to target and kill cancer cells because cancer cells have unique characteristics such as a high negative charge and abundance of microvilli in the cell membrane when compared to a normal cell. ACPs have several advantages, such as high specificity, cost-effectiveness, low immunogenicity, minimal toxicity, and high tolerance under normal physiological conditions. However, the development and identification of ACPs are time-consuming and expensive in traditional wet-lab-based approaches. Thus, the application of artificial intelligence on the approaches can save time and reduce the cost to identify candidate ACPs. Recently, machine learning (ML), deep learning (DL), and hybrid learning (ML combined DL) have emerged into the development of ACPs without experimental analysis, owing to advances in computer power and big data from the power system. Additionally, we suggest that combination therapy with classical approaches and ACPs might be one of the impactful approaches to increase the efficiency of cancer therapy.

A carrier-free supramolecular nanoprodrug based on lactose-functionalized dimeric camptothecin via self-assembly in water for targeted and fluorescence imaging-guided chemo-photodynamic therapy

Most carrier-based nano drug delivery systems (nano-DDSs) are subjected to complex preparation or purification processes, metabolic instability and potential systemic toxicity. To overcome these issues, it is urgent to develop a multifunctional carrier-free nano-DDS that can be fabricated by a simple approach for enhanced anticancer efficacy. In this work, the carrier-free supramolecular nanoprodrug (CF SNPD) based on lactose (Lac) functionalized dimeric camptothecin (CPT) was developed, in which Lac and CPT were conjugated by the aromatized thioacetal (ATA, a reactive oxygen species (ROS)-responsive bond). The obtained Lac-ATA-CPT₂ prodrug and the photosensitizer Chlorin e6 (Ce6) formed CF SNPD (denoted as Ce6@Lac-ATA-CPT₂ NPs) in water by supramolecular self-assembly. The design of dimeric CPT endowed Ce6@Lac-ATA-CPT₂ NPs with ultrahigh drug-loading capacity (up to 94%) and excellent stability. The Lac-functionalized CF SNPD displayed active specific targetability to HepG2 cells resulting from the carbohydrate-protein interactions. Furthermore, the fluorescence signal of Ce6 facilitated the precise tracking and localization of Ce6@Lac-ATA-CPT₂ NPs within the cell. Meanwhile, the ROS generated by Ce6 not only cleaved ATA linker to trigger on-demand CPT release, but also exhibited a killing effect on tumor cells, enabling synergistic therapy via CPT-mediated chemotherapy (CT) and Ce6-induced photodynamic therapy (PDT). Therefore, the multifunctional CF SNPD may be one of the promising therapeutic options for liver cancer.

A novel 3D terbium metal-organic framework as a heterogeneous Lewis acid catalyst for the cyanosilylation of aldehyde

A novel 3D lanthanide(iii) metal-organic framework (MOF) (namely Tb-MOF), was synthesized by self-assembly from Tb(iii) ion nitrate and the rigid organic ligand H₂sbdc (H₂sbdc = 5,5-dioxo-5H-dibenzo[b,d]thiophene-3,7-dicarboxylic acid), and could work as an efficient heterogeneous catalyst for the cyanosilylation of aromatic aldehydes at room temperature. The obtained Tb-MOF has been characterized and analysed in detail by single crystal X-ray diffraction, powder X-ray diffraction, thermogravimetric analysis and so on. The pores of Tb-MOF provided a microenvironment that was beneficial for the substrates to be close to the Lewis acid catalytic sites. The IR spectrogram and the fluorescence titration proved that the substrates could be activated inside the channel of Tb-MOF. The heterogeneous Tb-MOF catalyst with fine catalytic efficiency exhibited a high TON (TON = 460), and could be recycled at least three times without significantly reducing its activity.

Recent advances in Cu(II)/Cu(I)-MOFs based nano-platforms for developing new nano-medicines

With increasing world population, life-span of humans and spread of viruses, myriad of diseases in human beings are becoming more and more common. Because of the interesting chemical and framework versatility and porosity of metal organic frameworks (MOFs) they find application in varied areas viz. catalysis, sensing, metal ion/gas storage, chemical separation, drug delivery, bio-imaging. This subclass of coordination polymers having interesting three-dimensional framework exhibits inordinate potential and hence may find application in treatment and cure of cancer, diabetes Alzheimer's and other diseases. The presented review focuses on the diverse mechanism of action, unique biological activity and advantages of copper-based metal organic framework (MOF) nanomaterials in medicine. Also, different methods used in the treatment of cancer and other diseases have been presented and the applications as well as efficacy of copper MOFs have been reviewed and discussed. Eventually, the current-status and potential of copper based MOFs in the field of anti-inflammatory, anti-bacterial and anti-cancer therapy as well as further investigations going on for this class of MOF-based multifunctional nanostructures in for developing new nano-medicines have been presented.

Mutual Benefit between Cu(II) and Polydopamine for Improving Photothermal-Chemodynamic Therapy

Combination therapy has attracted extensive interest in alleviating the shortcomings of monotherapy and enhancing the treatment efficacy. In this work, hollow mesoporous silica nanoparticles (HMSNs) play the role of nanocarriers in the delivery of Cu(II)-doped polydopamine (PDA), termed as HMSNs@PDA-Cu, for synergistic therapy. PDA acts as a traditional photothermal agent to realize photothermal treatment (PTT). Chemodynamic therapy (CDT) is realized by the reaction of Cu(II) with intracellular glutathione (GSH), and subsequently, the generated Cu(I) reacts with H₂O₂ to produce toxic hydroxyl radical (^•OH) through a Fenton-like reaction. The photothermal performance of PDA is improved after its coordination with Cu(II). On the other hand, PDA exhibits superoxide dismutase (SOD)-mimicking activity. PDA converts O₂^•- to H₂O₂ and improves the production of H₂O₂, which promotes the therapeutic effect of CDT. Moreover, the high temperature caused by PTT further enhances the yield of ^•OH for CDT. This nanotheranostic platform perfectly applied to the tumor depletion of mice, presenting great potential for cancer metastasis therapy in vitro and in vivo.

Nanoscale metal-organic frameworks for tumor phototherapy

Metal-Organic Frameworks (MOFs) are constructed from metal ions/cluster nodes and functional organic ligands through coordination bonds. Owing to the advantages of diverse synthetic methods, easy modification after synthesis, large adsorption capacity for heavy metals, and short equilibrium time, considerable attention has recently been paid to MOFs for tumor phototherapy. Through rational tuning of metal ions and ligands, MOFs present abundant properties for various applications. Light-triggered phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is an emerging cancer treatment approach. Nanosized MOFs can be applied as phototherapeutic agents to accomplish phototherapy with excellent phototherapeutic efficacy. This review outlines the latest advances in the field of phototherapy with various metal ion-based MOFs.