Precise nanomedicine for intelligent therapy of cancer

Transferrin-targeting pH-responsive and biodegradable mesoporous silica nanohybrid for nitric oxide-sensitized chemotherapy of cancer

Weakly acidic pH, low oxygen and high glutathione levels are the main characteristics of tumor cells. Taking advantage of the unique acidic microenvironment of tumor cells, acid-responsive mesoporous organosilica nanoparticles (AMON) were designed for nitric oxide (NO)-sensitized chemotherapy of tumors. AMON served as a nanocarrier co-loaded with a nitric oxide donor (NOD) and chemotherapeutic drug doxorubicin (DOX). Transferrin (Tf) was modified on the surface as a targeting ligand to form NOD&DOX@AMON. In vitro experiments showed that AMON could be completely degraded under acidic conditions (pH 5.0) after 48 h. NOD&DOX@AMON entered cells via transferrin receptor-mediated internalization and degraded in the acidic microenvironment to release its payloads. NOD released NO in presence of one-electron reducing substances like Glutathione (GSH) and ascorbic acid, inhibiting P-glycoprotein(P-gp) function and thereby increasing the intracellular concentration of DOX. In vivo distribution studies revealed that the nanohybrids accumulated maximally in tumor tissue 12 h after intravenous injection and exhibited significant inhibitory effects on HepG2 xenograft tumors. Western blot experiments demonstrated that NOD&DOX@AMON could inhibit the expression of drug resistance-associated proteins and was expected to be employed as a therapeutic approach for drug-resistant ttumors.

Macrocycle-based self-assembled amphiphiles for co-delivery of therapeutic combinations to tumor

For tumor treatment, the efficiency of single chemotherapeutic agent is generally limited and the traditional combination chemotherapies frequently result in the aggravation of side effects. Herein, an amphiphilic pillararene-based self-assembled nanoparticle (APSN) composed of hydrazide-pillar[5]arene (HP5A-6C) that achieve effective co-delivery of therapeutic combinations was reported. Through integrating multitudinous macrocyclic cavities into a single nanoparticle, the APSN could co-load two antitumor drugs, cisplatin (CP) and nitrogen mustard (NM) via host-guest interactions. A serious of safety tests preliminary demonstrated that blank carrier APSN had good biocompatibility. Cytotoxicity assay verified that co-delivery system CP+NM@APSN could exert a synergistic antitumor effect at the cellular level. In vivo studies demonstrated that CP+NM@APSN could not only improve chemotherapeutic outcomes in tumor-bearing model mouse but also alleviate two medications-related side effects. These favorable findings were attributed to the formation of ternary supramolecular assembly that benefited from an enhanced permeability and retention effect. © 2024 Elsevier Science. All rights reserved.

Pt/Pd dual-modified porphyrin metal-organic frameworks for NIR-II photothermal-enhanced photodynamic/catalytic therapy

Photodynamic therapy (PDT) and catalytic therapy were promising treatment modes, but tumor hypoxia and poor catalytic activity severely limited their efficacies. Herein, using a porphyrin metal-organic framework (PCN-224) as nanocarrier, a platinum/palladium (Pt/Pd) dual-modified PCN-224 nanoprobe (PCN-224-Pt@Pd) with strong peroxidase (POD)/catalase (CAT)-like activities was developed, achieving photothermal-promoted PDT/catalytic therapy. Compared with single ultrasmall Pt modifying, CAT-like activity of Pt/Pd dual-modifying increased oxygen concentration from 6.24 to 9.35 mg/L, which improved singlet oxygen (1O2) yield from 63.8 % to 82.9 %. Moreover, POD-like activity of Pt/Pd dual-modifying significantly accelerated hydroxyl radicals (·OH) generation. Importantly, PCN-224-Pt@Pd possessed near-infrared II (NIR-II) photothermal effect with a high efficiency (55.6 %), which further promoted ·OH production. Under combined therapy of PCN-224-Pt@Pd, the cell survival rate greatly reduced to 5.8 %, and the tumors were cured, suggesting NIR-II photothermal-enhanced PDT/catalytic therapy.

Enzymatic nanomotors with chemotaxis for product-based cancer therapy

The development of an intelligent nanomotor system holds great promise for enhancing the efficiency and effectiveness of antitumor therapy. Leveraging the overexpressed substances in the tumor microenvironment as propellants and chemotactic factors for enzyme-powered nanomotors represents a versatile and compelling approach. Herein, a plasma amine oxidase (PAO)-based chemotactic nanomotor system has been successfully developed, with the ability to enzymatically produce toxic acrolein and H2O2 from the upregulated polyamines (PAs) in the tumor microenvironment for active tumor therapy. Zwitterionic polymeric nanoparticles with superior biocompatibility are synthesized, followed by PAO modification via electrostatic interactions. As expected, the resulting nanomotor system exhibits positive chemotaxis toward PAs concentration gradient. Upon reaching the tumor region, our nanomotors, actuated by the tumor microenvironmental PAs, effectively enhance diffusion and enable deep penetration into the tumor site. This leads to the induction of tumor apoptosis and simultaneous inhibition of tumor invasion and migration by decomposing PAs into toxic products. By smartly utilizing the consumption of these local chemotactic factors and their enzymatic products, our nanomotor system provides a versatile and intelligent platform for active and enhanced tumor therapy.

Mechano-assisted strategies to improve cancer chemotherapy

Chemotherapy remains a cornerstone in cancer treatment; however, its effectiveness is frequently undermined by the development of drug resistance. Recent studies underscores the pivotal role of the tumor mechanical microenvironment (TMME) and the emerging field of mechanical nanomedicine in tackling chemo-resistance. This review offers an in-depth analysis of mechano-assisted strategies aimed at mitigating chemo-resistance through the modification of the TMME and the refinement of mechanical nanomedicine delivery systems. We explore the potential of targeting abnormal tumor mechanical properties as a promising avenue for enhancing the efficacy of cancer chemotherapy, which offers novel directions for advancing future cancer therapies, especially from the mechanomedicine perspective.

Precise Preparation of Supramolecular Spherical Nucleic Acids for Nucleolin-Targeted Gene Delivery

Molecular spherical nucleic acids (m-SNAs) are a second generation of spherical nucleic acids (SNAs), which are of significance in potential application of targeted delivery of nucleic acids or gene regulation due to their defined molecular structures. Nevertheless, m-SNAs typically involve a single DNA sequence which greatly limits its functions as either targeting purpose or gene regulation. In response, we proposed here a third generation, supramolecular spherical nucleic acids (Supra-SNAs) with two different sequences to achieve both above-mentioned functions. Specifically, we constructed a series of supramolecular self-assembly structures by coupling a cell membrane receptor (i.e., nucleolin)-recognizing aptamer (AS1411)-modified adamantine as targeting probe and human epithelial growth factor receptor 2 (HER2) antisense-functionalized β-cyclodextrin to specifically inhibit the overexpression of HER2 proteins for gene regulations. In comparison to the m-SNA precursors, such Supra-SNA structures exhibited enhanced levels of resistance to nuclease degradation, cellular uptake, gene regulation capabilities and tumor retention capacity. We demonstrated that Supra-SNAs exhibited optimal cell suppression rates and cell apoptosis via a phosphatidylinositol 3-kinase/protein kinase B signaling pathway. The well-defined molecular structures provide an attractive platform for investigating interrelationship between structure and property at the molecular level.

Advances in herbal polysaccharides-based nano-drug delivery systems for cancer immunotherapy

The boom in cancer immunotherapy has provided many patients with a better chance of survival, but opportunities often come with challenges. Single immunotherapy is not good enough to eradicate tumours, and often fails to achieve the desired therapeutic effect because of the low targeting of immunotherapy drugs, and causes more side effects. As a solution to this problem, researchers have developed several nano Drug Delivery Systems (NDDS) to deliver immunotherapeutic agents to achieve good therapeutic outcomes. However, traditional drug delivery systems (DDS) have disadvantages such as poor bioavailability, high cytotoxicity, and difficulty in synthesis, etc. Herbal Polysaccharides (HPS), derived from natural Chinese herbs, inherently possess low toxicity. Furthermore, the biocompatibility, biodegradability, hydrophilicity, ease of modification, and immunomodulatory activities of HPS offer unique advantages in substituting traditional DDS. This review initially addresses the current developments and challenges in immunotherapy. Subsequently, it focuses on the immunomodulatory mechanisms of HPS and their design as nanomedicines for targeted drug delivery in tumour immunotherapy. Our findings reveal that HPS-based nanomedicines exhibit significant potential in enhancing the efficacy of cancer immunotherapy, providing crucial theoretical foundations and practical guidelines for future clinical applications.

A single molecule carrier for ocular posterior segment diseases

Eye drops are envisaged as the most promising non-invasive formulation for the treatment of the ocular posterior segment diseases, while it is hindered by a series of complex ocular barriers, both static and dynamic in nature. In this context, we propose a single molecule nanomedicine based on host-guest chemistry to achieve highly efficient drug delivery targeted to ocular posterior segment. Sulfonated azocalix[4]arene (SAC4A) serves as the single molecule carrier, owing the multiple features of small size (24.0 Å in length, 21.2 Å in width, 14.8 Å in height with a Van der Waals volume of 930 Å3), negative charge, hydrophilicity, loading universality and hypoxia-triggered release. As a proof-of-concept, an eye drop formed by the complexation of SAC4A with sunitinib (SUN) is prepared to treat wet age-related macular degeneration (wAMD). SAC4A successfully transports SUN to the ocular posterior segment (the amount of SUN reaching the retinal-choroid tissue in the SUN@SAC4A group was 2.47 times larger than that in the SUN group at 30 min), significantly enhancing its anti-choroidal neoangiogenesis effect of SUN to wAMD, which played a key role in the treatment. We believe that the single molecule nanomedicine paradigm is highly amenable for treating various ocular posterior segment diseases in the future.

Stimuli-Responsive Polymeric Nanocarriers Accelerate On-Demand Drug Release to Combat Glioblastoma

Glioblastoma multiforme (GBM) is a highly malignant brain tumor with a poor prognosis and limited treatment options. Drug delivery by stimuli-responsive nanocarriers holds great promise for improving the treatment modalities of GBM. At the beginning of the review, we highlighted the stimuli-active polymeric nanocarriers carrying therapies that potentially boost anti-GBM responses by employing endogenous (pH, redox, hypoxia, enzyme) or exogenous stimuli (light, ultrasonic, magnetic, temperature, radiation) as triggers for controlled drug release mainly via hydrophobic/hydrophilic transition, degradability, ionizability, etc. Modifying these nanocarriers with target ligands further enhanced their capacity to traverse the blood-brain barrier (BBB) and preferentially accumulate in glioma cells. These unique features potentially lead to more effective brain cancer treatment with minimal adverse reactions and superior therapeutic outcomes. Finally, the review summarizes the existing difficulties and future prospects in stimuli-responsive nanocarriers for treating GBM. Overall, this review offers theoretical guidelines for developing intelligent and versatile stimuli-responsive nanocarriers to facilitate precise drug delivery and treatment of GBM in clinical settings.

Tuning stiffness of hyaluronan-cholesterol nanogels by mussel-inspired dopamine-Fe3+ coordination: Preparation and properties evaluation

In the evolving field of nanomedicine, tailoring the mechanical properties of nanogels to fine-tune their biological performance is a compelling avenue of research. This work investigates an innovative method for modulating the stiffness of hyaluronan-cholesterol (HACH) nanogels, an area that remains challenging. By grafting dopamine (DOPA) onto the HA backbone, characterized through UV, 1H NMR, and FT-IR analyses, we synthesized a novel polymer that spontaneously forms nanogels in aqueous environments. These HACH-DOPA nanogels are characterized by their small size (~170 nm), negative charge (around -32 mV), high stability, efficient drug encapsulation, and potent antioxidant activities (measured by ABTS test). Leveraging mussel-inspired metal coordination chemistry, the DOPA moieties enable stiffness modulation of the nanogels through catechol-Fe3+ interactions. This modification leads to increased crosslinking and, consequently, nanogels with a significantly increased stiffness, as measured by atomic force microscopy (AFM), with the formation of the HACH-DOPA@Fe3+ complex being pH-dependent and reversible. The cytocompatibility was evaluated via WST-1 cell proliferation assays on HUVEC and HDF cell lines, showing no evident cytotoxicity. Furthermore, the modified nanogels demonstrated enhanced cellular uptake, suggesting their substantial potential for intracellular drug delivery applications, a hypothesis supported by confocal microscopy assays. This work not only provides valuable insight into modulating nanogel stiffness but also advances new nanosystems for promising biomedical applications.

Custom-Design of Multi-Stimuli-Responsive Degradable Silica Nanoparticles for Advanced Cancer-Specific Chemotherapy

Chemotherapy is crucial in oncology for combating malignant tumors but often encounters obatacles such as severe adverse effects, drug resistance, and biocompatibility issues. The advantages of degradable silica nanoparticles in tumor diagnosis and treatment lie in their ability to target drug delivery, minimizing toxicity to normal tissues while enhancing therapeutic efficacy. Moreover, their responsiveness to both endogenous and exogenous stimuli opens up new possibilities for integrating multiple treatment modalities. This review scrutinizes the burgeoning utility of degradable silica nanoparticles in combination with chemotherapy and other treatment modalities. Commencing the elucidation of degradable silica synthesis and degradation mechanisms, emphasis is placed on the responsiveness of these materials to endogenous (e.g., pH, redox reactions, hypoxia, and enzymes) and exogenous stimuli (e.g., light and high-intensity focused ultrasound). Moreover, this exploration delves into strategies harnessing degradable silica nanoparticles in chemotherapy alone, coupled with radiotherapy, photothermal therapy, photodynamic therapy, gas therapy, immunotherapy, starvation therapy, and chemodynamic therapy, elucidating multimodal synergies. Concluding with an assessment of advances, challenges, and constraints in oncology, despite hurdles, future investigations are anticipated to augment the role of degradable silica in cancer therapy. These insights can serve as a compass for devising more efficacious combined tumor treatment strategies.

A functionalized cell membrane biomimetic nanoformulation based on layered double hydroxide for combined tumor chemotherapy and sonodynamic therapy

The development of nanoformulations with simple compositions that can exert targeted combination therapy still remains a great challenge in the area of precision cancer nanomedicine. Herein, we report the design of a multifunctional nanoplatform based on methotrexate (MTX)-loaded layered double hydroxide (LDH) coated with chlorin e6 (Ce6)-modified MCF-7 cell membranes (CMM) for combined chemo/sonodynamic therapy of breast cancer. LDH nanoparticles were in situ loaded with MTX via coprecipitation, and coated with CMM that were finally functionalized with phospholipid-modified Ce6. The created nanoformulation of LDH-MTX@CMM-Ce6 displays good colloidal stability under physiological conditions and can release MTX in a pH-dependent manner. We show that the formulation can homologously target breast cancer cells, and induce their significant apoptosis through arresting the cell cycle via cooperative MTX-based chemotherapy and ultrasound (US)-activated sonodynamic therapy. The assistance of US can not only trigger sonosensitizer Ce6 to produce reactive oxygen species, but also enhance the cellular uptake of LDH-MTX@CMM-Ce6 via an acoustic cavitation effect. Upon intravenous injection and US irradiation, LDH-MTX@CMM-Ce6 displays an admirable antitumor performance towards a xenografted breast tumor mouse model. Furthermore, the modification of Ce6 on the CMM endows the LDH-based nanoplatform with fluorescence imaging capability. The developed LDH-based nanoformulation here provides a general intelligent cancer nanomedicine platform with simple composition and homologous targeting specificity for combined chemo/sonodynamic therapy and fluorescence imaging of tumors.

Softness-Aided Mild Hyperthermia Boosts Stiff Nanomedicine by Regulating Tumor Mechanics

Aberrant tumor mechanical microenvironment (TMME), featured with overactivated cancer-associated fibroblasts (CAFs) and excessive extracellular matrix (ECM), severely restricts penetration and accumulation of cancer nanomedicines, while mild-hyperthermia photothermal therapy (mild-PTT) has been developed to modulate TMME. However, photothermal agents also encounter the barriers established by TMME, manifesting in limited penetration and heterogeneous distribution across tumor tissues and ending with attenuated efficiency in TMME regulation. Herein, it is leveraged indocyanine green (ICG)-loaded soft nanogels with outstanding deformability, for efficient tumor penetration and uniform distribution, in combination with mild-PTT to achieve potent TMME regulation by inhibiting CAFs and degrading ECM. As a result, doxorubicin (DOX)-loaded stiff nanogels gain greater benefits in tumor penetration and antitumor efficacy than soft counterparts from softness-mediated mild-PTT. This study reveals the crucial role of nanomedicine mechanical properties in tumor distribution and provides a novel strategy for overcoming the barriers of solid tumors with soft deformable nanogels.

Enhancing cancer immunotherapy: Exploring strategies to target the PD-1/PD-L1 axis and analyzing the associated patent, regulatory, and clinical trial landscape

Cancer treatment modalities and their progression is guided by the specifics of cancer, including its type and site of localization. Surgery, radiation, and chemotherapy are the most often used conventional treatments. Conversely, emerging treatment techniques include immunotherapy, hormone therapy, anti-angiogenic therapy, dendritic cell-based immunotherapy, and stem cell therapy. Immune checkpoint inhibitors' anticancer properties have drawn considerable attention in recent studies in the cancer research domain. Programmed Cell Death Protein-1 (PD-1) and its ligand (PD-L1) checkpoint pathway are key regulators of the interactions between activated T-cells and cancer cells, protecting the latter from immune destruction. When the ligand PD-L1 attaches to the receptor PD-1, T-cells are prevented from destroying cells that contain PD-L1, including cancer cells. The PD-1/PD-L1 checkpoint inhibitors block them, boosting the immune response and strengthening the body's defenses against tumors. Recent years have seen incredible progress and tremendous advancement in developing anticancer therapies using PD-1/PD-L1 targeting antibodies. While immune-related adverse effects and low response rates significantly limit these therapies, there is a need for research on methods that raise their efficacy and lower their toxicity. This review discusses various recent innovative nanomedicine strategies such as PLGA nanoparticles, carbon nanotubes and drug loaded liposomes to treat cancer targeting PD-1/PD-L1 axis. The biological implications of PD-1/PD-L1 in cancer treatment and the fundamentals of nanotechnology, focusing on the novel strategies used in nanomedicine, are widely discussed along with the corresponding guidelines, clinical trial status, and the patent landscape of such formulations.

Polyethyleneimine surface-modified silver-selenium nanocomposites for anti-infective treatment of wounds by disrupting biofilms

Bacterial biofilm formation is associated with the pathogenicity of pathogens and poses a serious threat to human health and clinical therapy. Complex biofilm structures provide physical barriers that inhibit antibiotic penetration and inactivate antibiotics via enzymatic breakdown. The development of biofilm-disrupting nanoparticles offers a promising strategy for combating biofilm infections. Hence, polyethyleneimine surface-modified silver-selenium nanocomposites, Ag@Se@PEI (ASP NCs), were designed for synergistic antibacterial effects by destroying bacterial biofilms to promote wound healing. The results ofin vitroantimicrobial experiments showed that, ASP NCs achieved efficient antibacterial effects againstStaphylococcus aureus (S. aureus)andEscherichia coli (E. coli)by disrupting the formation of the bacterial biofilm, stimulating the outbreak of reactive oxygen species and destroying the integrity of bacterial cell membranes. Thein-vivobacterial infection in mice model showed that, ASP NCs further promoted wound healing and new tissue formation by reducing inflammatory factors and promoting collagen fiber formation which efficiently enhanced the antibacterial effect. Overall, ASP NCs possess low toxicity and minimal side effects, coupled with biocompatibility and efficient antibacterial properties. By disrupting biofilms and bacterial cell membranes, ASP NCs reduced inflammatory responses and accelerated the healing of infected wounds. This nanocomposite-based study offers new insights into antibacterial therapeutic strategies as potential alternatives to antibiotics for wound healing.

Supramolecular 3 in 1: A Lubrication and Co-Delivery System for Synergistic Advanced Osteoarthritis Therapy

The complexity, heterogeneity, and drug resistance of diseases necessitate a shift in therapeutic paradigms from monotherapy to combination therapy, which could augment treatment efficiency. Effective treatment of advanced osteoarthritis (OA) requires addressing three key factors contributing to its deterioration: chronic joint inflammation, lubrication dysfunction, and cartilage-tissue degradation. Herein, we present a supramolecular nanomedicine of multifunctionality via molecular recognition and self-assembly. The employed macrocyclic carrier, zwitterion-modified cavitand (CV-2), not only accurately loads various drugs but also functions as a therapeutic agent with lubricating properties for the treatment of OA. Kartogenin (KGN), a drug for articular cartilage regeneration and protection, and flurbiprofen (FP), an anti-inflammatory agent, were coloaded onto CV-2 assembly, forming a supramolecular nanomedicine KGN&FP@CV-2. The three-in-one combination therapy of KGN&FP@CV-2 addresses the three pathological features for treating OA collectively, and thus provides long-term therapeutic benefits for OA through sustained drug release and intrinsic lubrication in vivo. The multifunctional integration of macrocyclic delivery and therapeutics provides a simple, flexible, and universal platform for the synergistic treatment of diseases involving multiple drugs.

Theranostic Bottle-Brush Polymers Tailored for Universal Solid-Tumor Targeting

Designing an efficient nanocarrier to target multiple types of cancer remains a major challenge in the development of cancer nanomedicines. The majority of systemically administered nanoparticles (NPs) are rapidly cleared by the liver, resulting in poor tumor-targeting efficiency and severe side effects. Here, we present a delicately tailored design and synthesis of fluorescent bottle-brush polymers and screen nine derived NPs, each varying in size and surface coatings, for tumor imaging and targeted delivery. Our optimized polymer bearing (oligo(ethylene glycol) methyl ether methacrylate) in the side chains shows reduced macrophage uptake, prolonged blood-circulation time (up to 27 h), and exceptionally high accumulation in the tumor compared to the liver, elucidating an immune-evasion-induced tumor-targeting mechanism. High tumor accumulation significantly improved the antitumor efficacy. The outstanding tumor-targeting ability has been further validated across five distinct tumor models, including orthotopic glioblastoma and pancreatic cancer, which demonstrate the universality of our polymeric nanocarrier for tumor-targeting delivery.

Intelligent Biomaterialomics: Molecular Design, Manufacturing, and Biomedical Applications

Materialomics integrates experiment, theory, and computation in a high-throughput manner, and has changed the paradigm for the research and development of new functional materials. Recently, with the rapid development of high-throughput characterization and machine-learning technologies, the establishment of biomaterialomics that tackles complex physiological behaviors has become accessible. Breakthroughs in the clinical translation of nanoparticle-based therapeutics and vaccines have been observed. Herein, recent advances in biomaterials, including polymers, lipid-like materials, and peptides/proteins, discovered through high-throughput screening or machine learning-assisted methods, are summarized. The molecular design of structure-diversified libraries; high-throughput characterization, screening, and preparation; and, their applications in drug delivery and clinical translation are discussed in detail. Furthermore, the prospects and main challenges in future biomaterialomics and high-throughput screening development are highlighted.

A Polymeric Nanoparticle to Co-Deliver Mitochondria-Targeting Peptides and Pt(IV) Prodrug: Toward High Loading Efficiency and Combination Efficacy

Developing combination chemotherapy systems with high drug loading efficiency at predetermined drug ratios to achieve a synergistic effect is important for cancer therapy. Herein, a polymeric dual-drug nanoparticle composed of a Pt(IV) prodrug derived from oxaliplatin and a mitochondria-targeting cytotoxic peptide is constructed through emulsion interfacial polymerization, which processes high drug loading efficiency and high biocompatibility. The depolymerization of polymeric dual-drug nanoparticle and the activation of Pt prodrug can be effectively triggered by the acidic tumor environment extracellularly and the high levels of glutathione intracellularly in cancer cells, respectively. The utilization of mitochondria-targeting peptide can inhibit ATP-dependent processes including drug efflux and DNA damage repair. This leads to increased accumulation of Pt-drugs within cancer cells. Eventually, the polymeric dual-drug nanoparticle demonstrates appreciable antitumor effects on both cell line derived and patient derived xenograft lung cancer model. It is highly anticipated that the polymeric dual-or multi-drug systems can be applied for combination chemotherapy to achieve enhanced anticancer activity and reduced side effects.

Active targeting tumor therapy using host-guest drug delivery system based on biotin functionalized azocalix[4]arene

Host-guest drug delivery systems (HGDDSs) provided a facile method for incorporating biomedical functions, including efficient drug-loading, passive targeting, and controlled drug release. However, developing HGDDSs with active targeting is hindered by the difficult functionalization of popular macrocycles. Herein, we report an active targeting HGDDS based on biotin-modified sulfonated azocalix[4]arene (Biotin-SAC4A) to efficiently deliver drug into cancer cells for improving anti-tumor effect. Biotin-SAC4A was synthesized by amide condensation and azo coupling. Biotin-SAC4A demonstrated hypoxia responsive targeting and active targeting through azo and biotin groups, respectively. DOX@Biotin-SAC4A, which was prepared by loading doxorubicin (DOX) in Biotin-SAC4A, was evaluated for tumor targeting and therapy in vitro and in vivo. DOX@Biotin-SAC4A formulation effectively killed cancer cells in vitro and more efficiently delivered DOX to the lesion than the similar formulation without active targeting. Therefore, DOX@Biotin-SAC4A significantly improved the in vivo anti-tumor effect of free DOX. The facilely prepared Biotin-SAC4A offers strong DOX complexation, active targeting, and hypoxia-triggered release, providing a favorable host for effective breast cancer chemotherapy in HGDDSs. Moreover, Biotin-SAC4A also has potential to deliver agents for other therapeutic modalities and diseases.

Nanocatalysts for modulating antitumor immunity: fabrication, mechanisms and applications

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

Predictive, preventive, and personalized medicine in breast cancer: targeting the PI3K pathway

Breast cancer (BC) is a multifaceted disease characterized by distinct molecular subtypes and varying responses to treatment. In BC, the phosphatidylinositol 3-kinase (PI3K) pathway has emerged as a crucial contributor to the development, advancement, and resistance to treatment. This review article explores the implications of the PI3K pathway in predictive, preventive, and personalized medicine for BC. It emphasizes the identification of predictive biomarkers, such as PIK3CA mutations, and the utility of molecular profiling in guiding treatment decisions. The review also discusses the potential of targeting the PI3K pathway for preventive strategies and the customization of therapy based on tumor stage, molecular subtypes, and genetic alterations. Overcoming resistance to PI3K inhibitors and exploring combination therapies are addressed as important considerations. While this field holds promise in improving patient outcomes, further research and clinical trials are needed to validate these approaches and translate them into clinical practice.

Synthesis of flaxseed gum/melanin-based scaffold: A novel approach for nano-encapsulation of doxorubicin with enhanced anticancer activity

Doxorubicin is a powerful chemotherapy medicine that is frequently used to treat cancer, but because of its extremely destructive side effects on other healthy cells, its applications have been severely constrained. With the aim of using lower therapeutic doses of doxorubicin while maintaining the same anti-cancerous activity as those of higher doses, the present study designs nano-encapsulation of doxorubicin by acrylamide grafted melanin as core and acrylic acid grafted flax seed gum as shell (DOX@AAM-g-ML/AA-g-FSG-NPs) for studies in-vivo and in-vitro anticancer activity. For biological studies, the cytotoxicity of DOX@AAM-g-ML/AA-g-FSG-NPs was examined on a cancerous human cell line (HCT-15) and it was observed that DOX@AAM-g-ML/AA-g-FSG-NPs exhibited very high toxicity towards HCT-15. In-vivo investigation in colon cancer-inflicted rat model also showed that DOX@AAM-g-ML/AA-g-FSG-NPs showed better anticancer activity against cancerous cells as compared to free doxorubicin. The drug release behavior of DOX@GML-GFS-NPs was studied at several pH and maximum drug release (95 %) was recorded at pH -7.2, and kinetic data of drug release was follows the Higuchi (R2 = 0.9706) kinetic model. Our study is focussed on reducing the side effects of doxorubicin by its nano-encapsulation in acrylamide grafted melanin as core and acrylic acid grafted flax seed gum that will also enhance its efficiency.

Nano-phototherapy: Favorable prospects for cancer treatment

Nanotechnology-based phototherapies have drawn interest in the fight against cancer because of its noninvasiveness, high flexibility, and precision in terms of cancer targeting and drug delivery based on its surface properties and size. Phototherapy has made remarkable development in recent decades. Approaches to phototherapy, which utilize nanomaterials or nanotechnology have emerged to contribute to advances around nanotechnologies in medicine, particularly for cancers. A brief overviews of the development of photodynamic therapy as well as its mechanism in cancer treatment is provided. We emphasize the design of novel nanoparticles utilized in photodynamic therapy while summarizing the representative progress during the recent years. Finally, to forecast important future research in this area, we examine the viability and promise of photodynamic therapy systems based on nanoparticles in clinical anticancer treatment applications and briefly make mention of the elimination of all reactive metabolites pertaining to nano formulations inside living organisms providing insight into clinical mechanistic processes. Future developments and therapeutic prospects for photodynamic treatments are anticipated. Our viewpoints might encourage scientists to create more potent phototherapy-based cancer therapeutic modalities. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Supramolecular self-assembled peptide-engineered nanofibers: A propitious proposition for cancer therapy

Cancer is a devastating disease that causes a substantial number of deaths worldwide. Current therapeutic interventions for cancer include chemotherapy, radiation therapy, or surgery. These conventional therapeutic approaches are associated with disadvantages such as multidrug resistance, destruction of healthy tissues, and tissue toxicity. Therefore, there is a paradigm shift in cancer management wherein nanomedicine-based novel therapeutic interventions are being explored to overcome the aforementioned disadvantages. Supramolecular self-assembled peptide nanofibers are emerging drug delivery vehicles that have gained much attention in cancer management owing to their biocompatibility, biodegradability, biomimetic property, stimuli-responsiveness, transformability, and inherent therapeutic property. Supramolecules form well-organized structures via non-covalent linkages, the intricate molecular arrangement helps to improve tissue permeation, pharmacokinetic profile and chemical stability of therapeutic agents while enabling targeted delivery and allowing efficient tumor imaging. In this review, we present fundamental aspects of peptide-based self-assembled nanofiber fabrication their applications in monotherapy/combinatorial chemo- and/or immuno-therapy to overcome multi-drug resistance. The role of self-assembled structures in targeted/stimuli-responsive (pH, enzyme and photo-responsive) drug delivery has been discussed along with the case studies. Further, recent advancements in peptide nanofibers in cancer diagnosis, imaging, gene therapy, and immune therapy along with regulatory obstacles towards clinical translation have been deliberated.

EGFR-targeted humanized single chain antibody fragment functionalized silica nanoparticles for precision therapy of cancer

The combination of highly specific targeting ability and potent killing effect has made antibody-drug conjugates (ADCs) a popular area of focus in the development of anti-cancer drugs. However, the large molecular weight of IgG antibodies (∼ 150 kDa) often faces challenges in penetrating capillaries and stroma in tumor tissue. Moreover, when the drug-antibody ratio (DAR) is too low (DAR < 2) or too high (DAR > 6) it decreases the effectiveness of the ADC and further increases the potential for aggregation, overall clearance of the early system payload, and release rate. In this study, an EGFR-based single-chain antibody fragment (husA)-human serum albumin (HSA)-coupled FITC-labeled mesoporous silica nanoparticle (FMSN-DOX-H-husA) was developed. Chinese hamster ovarian cells express the husA, which is a single chain antibody fragment of the EGFR that has been humanized. The small molecular weight of the single chain antibody allows for shorter penetration into solid tumors and the absence of adverse effects of the Fc fragment. The modification of HSA improves the safety of the antibody nanoparticle couples by both improving the biocompatibility of the nanoparticles, prolonging the circulation time of the nanoparticles, and avoiding early release of the payload. Also, the humanization substantially reduces the immunogenicity. More importantly, the ratio of drug antibodies on nanoparticles was experimentally and computationally derived to be 11.8, providing a more accurate guide for clinical trials. The results of both in vivo and in vitro experiments indicated promising antitumor activity and safety of FMSN-DOX-H-husA. Thus, this antibody-drug conjugate provided a hopeful option for cancer treatment.

Multistage Self-Assembled Nanomaterials for Cancer Immunotherapy

Advances in nanotechnology have brought innovations to cancer therapy. Nanoparticle-based anticancer drugs have achieved great success from bench to bedside. However, insufficient therapy efficacy due to various physiological barriers in the body remains a key challenge. To overcome these biological barriers and improve the therapeutic efficacy of cancers, multistage self-assembled nanomaterials with advantages of stimuli-responsiveness, programmable delivery, and immune modulations provide great opportunities. In this review, we describe the typical biological barriers for nanomedicines, discuss the recent achievements of multistage self-assembled nanomaterials for stimuli-responsive drug delivery, highlighting the programmable delivery nanomaterials, in situ transformable self-assembled nanomaterials, and immune-reprogramming nanomaterials. Ultimately, we perspective the future opportunities and challenges of multistage self-assembled nanomaterials for cancer immunotherapy.

A Detailed Insight into the Effects of Morphologies of Cerium Oxide on Fenton-like Reactions for Different Applications

As an exceptional Fenton-like reagent, cerium oxide (CeO2 ) finds applications in biomedical science and organic pollutants treatment. The Fenton-like reaction catalyzed by CeO2 typically encompasses two distinct processes: one resembling the classical Fenton reaction, wherein cerium (Ce3+ ) triggers the decomposition of hydrogen peroxide (H2 O2 ) to yield reactive oxygen species (ROS), and the other involves the complexation of H2 O2 on the Ce3+ surface, leading to the formation of peroxides. However, the influence of diverse CeO2 morphologies on these two reaction pathways has not been comprehensively explored. In this study, CeO2 exhibiting three typical morphologies, rods, cubes, and spheres, were prepared. The generation of ROS and peroxides was evaluated using the 3,3,5,5-tetramethylbenzidine (TMB) oxidation reaction and the reduction current of H2 O2 , respectively. Moreover, the impacts of pH variations and CeO2 /H2 O2 concentrations on the production and conversion of these two reaction products were investigated. To corroborate the distinctions between the resultant products and their applicability, apoptosis assays and acid orange 7 (AO7) degradation analyses were performed. Notably, CeO2 rods exhibited the highest proportion of Ce3+ , predominantly engaging in complexation with H2 O2 to foster peroxide formation, thereby facilitating the robust degradation of AO7. However, the generated peroxides appeared to occupy Ce3+ sites, thereby impeding the H2 O2 decomposition process. Conversely, Ce3+ species on the surface of CeO2 cubes were primarily involved in H2 O2 decomposition, leading to heightened ROS production, and thus showcasing substantial potential for damaging A549 tumor cells. It is worth noting that the ability of these Ce3+ species to form peroxides through complexation with H2 O2 was comparatively reduced. In summation, this study sheds light on the intricate interplay between distinct CeO2 morphologies and their divergent impacts on Fenton-like reactions. These findings expand our comprehension of the influences on its reactivity of CeO2 morphologies and open new insights for applications in diverse domains, from organic dye degradation to tumor therapy.

Synthesis of Multifunctional Mn3O4-Ag2S Janus Nanoparticles for Enhanced T1-Magnetic Resonance Imaging and Photo-Induced Tumor Therapy

The global burden of cancer is increasing rapidly, and nanomedicine offers promising prospects for enhancing the life expectancy of cancer patients. Janus nanoparticles (JNPs) have garnered considerable attention due to their asymmetric geometry, enabling multifunctionality in drug delivery and theranostics. However, achieving precise control over the self-assembly of JNPs in solution at the nanoscale level poses significant challenges. Herein, a low-temperature reversed-phase microemulsion system was used to obtain homogenous Mn3O4-Ag2S JNPs, which showed significant potential in cancer theranostics. Structural characterization revealed that the Ag2S (5-10 nm) part was uniformly deposited on a specific surface of Mn3O4 to form a Mn3O4-Ag2S Janus morphology. Compared to the single-component Mn3O4 and Ag2S particles, the fabricated Mn3O4-Ag2S JNPs exhibited satisfactory biocompatibility and therapeutic performance. Novel diagnostic and therapeutic nanoplatforms can be guided using the magnetic component in JNPs, which is revealed as an excellent T1 contrast enhancement agent in magnetic resonance imaging (MRI) with multiple functions, such as photo-induced regulation of the tumor microenvironment via producing reactive oxygen species and second near-infrared region (NIR-II) photothermal excitation for in vitro tumor-killing effects. The prime antibacterial and promising theranostics results demonstrate the extensive potential of the designed photo-responsive Mn3O4-Ag2S JNPs for biomedical applications.

Polysaccharide-Based Nanogels to Overcome Mucus, Skin, Cornea, and Blood-Brain Barriers: A Review

Nanocarriers have been extensively developed in the biomedical field to enhance the treatment of various diseases. However, to effectively deliver therapeutic agents to desired target tissues and enhance their pharmacological activity, these nanocarriers must overcome biological barriers, such as mucus gel, skin, cornea, and blood-brain barriers. Polysaccharides possess qualities such as excellent biocompatibility, biodegradability, unique biological properties, and good accessibility, making them ideal materials for constructing drug delivery carriers. Nanogels, as a novel drug delivery platform, consist of three-dimensional polymer networks at the nanoscale, offering a promising strategy for encapsulating different pharmaceutical agents, prolonging retention time, and enhancing penetration. These attractive properties offer great potential for the utilization of polysaccharide-based nanogels as drug delivery systems to overcome biological barriers. Hence, this review discusses the properties of various barriers and the associated constraints, followed by summarizing the most recent development of polysaccharide-based nanogels in drug delivery to overcome biological barriers. It is expected to provide inspiration and motivation for better design and development of polysaccharide-based drug delivery systems to enhance bioavailability and efficacy while minimizing side effects.

L-Arginine self-delivery supramolecular nanodrug for NO gas therapy

NO gas therapy is a supplementary approach for tumor treatment due to the advantages of minimal invasion, little drug resistance, low side effect and amplified efficacy. l-Arginine (L-Arg), a natural NO source with good biocompatibility, can release NO under the stimulation of H2O2 in tumor microenvironment. However, the conventional l-Arg delivery systems via noncovalent loading usually lead to inevitable premature leakage of nano-cargos during blood circulation. In this work, an efficient l-Arg self-delivery supramolecular nanodrug (SDSND) for tumor treatment is demonstrated by combining Mannich reaction and π-π stacking. l-Arg links to (-)-epigallocatechin gallate (EGCG) with the assistance of formaldehyde through Mannich reaction, and then assembles into nanometer-sized particles via π-π stacking. The guanidine group of l-Arg and the phenolic hydroxyl groups of EGCG are preserved in the SDSNDs, which allows for accomplishing gas therapy by provoking tumor cell apoptosis and combining with EGCG to amplify apoptosis, respectively. In addition, the SDSNDs exhibit high biocompatibility and avoid the premature leakage of l-Arg in blood circulation, providing an alternative l-Arg delivery system for NO gas therapy. STATEMENT OF SIGNIFICANCE: NO gas therapy has attracted emerging interest in tumor treatment. However, the controlled NO release and the avoidance of premature leakage of NO donors remain challenging. In this work, L-Arginine (L-Arg) self-delivery supramolecular nanodrug for efficient tumor therapy is demonstrated through the Mannich reaction of L-Arg, (-)-epigallocatechin gallate (EGCG) and formaldehyde. Stimulated by tumor microenvironment, the guanidine groups of L-Arg allow for accomplishing NO release and thus provoking tumor cell apoptosis. The nanodrug also avoids the premature leakage of L-Arg in blood circulation. Moreover, the preserved phenolic hydroxyl groups of EGCG combine with L-Arg to amplify apoptosis. The nanodrug exhibits high biocompatibility and good therapeutic effect, providing an alternative L-Arg delivery system for NO gas therapy.

Soft Bioelectronics for Therapeutics

Soft bioelectronics play an increasingly crucial role in high-precision therapeutics due to their softness, biocompatibility, clinical accuracy, long-term stability, and patient-friendliness. In this review, we provide a comprehensive overview of the latest representative therapeutic applications of advanced soft bioelectronics, ranging from wearable therapeutics for skin wounds, diabetes, ophthalmic diseases, muscle disorders, and other diseases to implantable therapeutics against complex diseases, such as cardiac arrhythmias, cancer, neurological diseases, and others. We also highlight key challenges and opportunities for future clinical translation and commercialization of soft therapeutic bioelectronics toward personalized medicine.

A PD-L1 targeting nanotheranostic for effective photoacoustic imaging guided photothermal-immunotherapy of tumor

Tumor immunotherapy has been partly effective for specific cancers. However, problems such as low immune response, limited antitumor effectiveness, and high antibody costs still persist. Synergistic therapeutic approaches, such as immune checkpoint inhibition in conjunction with photothermal therapy and photoacoustic imaging, are expected to provide approaches for more precise and efficient immunotherapy of tumors. Furthermore, developing alternatives for antibodies, such as PD-L1 aptamers and nanocarriers, would reduce the cost of tumor immunotherapy. Herein, we develop a PD-L1-targeting nanotheranostic to block immune checkpoints for synergistic photothermal-immunotherapy against tumors, along with effective photoacoustic (PA) imaging. The nanotheranostic is synthesized by the modification of gold nanorods (GNRs) with the PD-L1 aptamer (APDL1), which can sensitively and specifically recognize PD-L1 on the tumor cell surface, and mediate nanoparticle accumulation and strong PA signals in tumors. The aptamer is released from GNR through a competition of glutathione (GSH) and is then functionalized as a PD-L1 blockade. In collaboration with the concurrent photothermal therapy, antitumor immunity is significantly augmented by enhancing the filtration of matured dendritic cells and suppressing regulatory T cells, followed by the activation of cytotoxic T cells and inhibition of T cell exhaustion. Such a nanotheranostic modality effectively suppresses tumor growth in mice, representing an appealing platform for both biological imaging and photoimmunotherapy of tumors.

Nanoparticles with transformable physicochemical properties for overcoming biological barriers

In recent years, tremendous progress has been made in the development of nanomedicines for advanced therapeutics, yet their unsatisfactory targeting ability hinders the further application of nanomedicines. Nanomaterials undergo a series of processes, from intravenous injection to precise delivery at target sites. Each process faces different or even contradictory requirements for nanoparticles to pass through biological barriers. To overcome biological barriers, researchers have been developing nanomedicines with transformable physicochemical properties in recent years. Physicochemical transformability enables nanomedicines to responsively switch their physicochemical properties, including size, shape, surface charge, etc., thus enabling them to cross a series of biological barriers and achieve maximum delivery efficiency. In this review, we summarize recent developments in nanomedicines with transformable physicochemical properties. First, the biological dilemmas faced by nanomedicines are analyzed. Furthermore, the design and synthesis of nanomaterials with transformable physicochemical properties in terms of size, charge, and shape are summarized. Other switchable physicochemical parameters such as mobility, roughness and mechanical properties, which have been sought after most recently, are also discussed. Finally, the prospects and challenges for nanomedicines with transformable physicochemical properties are highlighted.

Copper-Zinc Bimetallic Single-Atom Catalysts with Localized Surface Plasmon Resonance-Enhanced Photothermal Effect and Catalytic Activity for Melanoma Treatment and Wound-Healing

Nanomaterials with photothermal combined chemodynamic therapy (PTT-CDT) have attracted the attention of researchers owing to their excellent synergistic therapeutic effects on tumors. Thus, the preparation of multifunctional materials with higher photothermal conversion efficiency and catalytic activity can achieve better synergistic therapeutic effects for melanoma. In this study, a Cu-Zn bimetallic single-atom (Cu/PMCS) is constructed with augmented photothermal effect and catalytic activity due to the localized surface plasmon resonance (LSPR) effect. Density functional theory calculations confirmed that the enhanced photothermal effect of Cu/PMCS is due to the appearance of a new d-orbital transition with strong spin-orbit coupling and the induced LSPR. Additionally, Cu/PMCS exhibited increased catalytic activity in the Fenton-like reaction and glutathione depletion capacity, further enhanced by increased temperature and LSPR. Consequently, Cu/PMCS induced better synergistic anti-melanoma effects via PTT-CDT than PMCS in vitro and in vivo. Furthermore, compared with PMCS, Cu/PMCS killed bacteria more quickly and effectively, thus facilitating wound healing owing to the enhanced photothermal effect and slow release of Cu2+ . Cu/PMCS promoted cell migration and angiogenesis and upregulated the expression of related genes to accelerate wound healing. Cu/PMCS has potential applications in treating melanoma and repairing wounds with its antitumor, antibacterial, and wound-healing properties.

Triple targeting host-guest drug delivery system based on lactose-modified azocalix[4]arene for tumor ablation

Host-guest drug delivery systems (HGDDSs) have been studied in an effort to modify the characteristics of therapeutic agents through noncovalent interactions, reduce toxic side effects and improve therapeutic effects. However, it is still an important task to continuously improve the targeting ability of HGDDSs, which is conducive to the development of precision medicine. Herein, we utilize the lactose-modified azocalix[4]arene (LacAC4A) as a triple targeting drug carrier customized for antitumor purposes. LacAC4A integrates three targeting features, passive targeting through the enhancing permeability and retention effect, active targeting by the interactions of lactose and the asialoglycoprotein receptors on the surface of tumor cells, and stimuli-responsive targeting via the reduction of the azo group under a hypoxia microenvironment. After loading doxorubicin (DOX) in LacAC4A, the supramolecular nanoformulation DOX@LacAC4A clearly showed the effective suppression of tumor growth through in vivo experiments. LacAC4A can achieve effective targeting, rapid release, and improve drug bioavailability. This design principle will provide a new material for drug delivery systems.

A mitochondria-targeting self-assembled carrier-free lonidamine nanodrug for redox-activated drug release to enhance cancer chemotherapy

Mitochondria play a vital role in maintaining cellular homeostasis. In recent years, studies have found that mitochondria have an important role in the occurrence and development of tumors, and targeting mitochondria has become a new strategy for tumor treatment. Lonidamine (LND), as a hexokinase inhibitor, can block the energy supply and destroy mitochondria. However, poor water solubility and low mitochondrial selectivity limit its clinical application. To overcome these obstacles, we report redox-activated self-assembled carrier-free nanoparticles (Cy-TK-LND NPs) based on a small molecule prodrug, in which photosensitizer IR780 (Cy) which targets mitochondria is conjugated to LND via a sensitive thioketal (TK) linker. Intracellular oxidative stress induced by laser radiation leads to the responsive cleavage of Cy-TK-LND NPs, facilitating the release of free LND into mitochondria. Subsequently, LND damages mitochondria, triggering the apoptosis pathway. The results show the effective killing effect of Cy-TK-LND NPs on cancer cells in vitro and in vivo. The IC50 value of irradiated Cy-TK-LND NPs is 5-fold lower than that of free LND. Moreover, tumor tissue section staining results demonstrate that irradiated Cy-TK-LND NPs induce necrosis and apoptosis of tumor cells, upregulate cytochrome C and pro-apoptotic Bax, and downregulate anti-apoptotic Bcl-2. Generally, Cy-TK-LND NPs exhibit efficient mitochondria-targeted delivery to improve the medicinal availability of LND. Accordingly, such a carrier-free prodrug-based nanomedicine holds promise as an effective cancer chemotherapy strategy.

Constructed Tumor-Targeted and MMP-2 Biocleavable Antibody Conjugated Silica Nanoparticles for Efficient Cancer Therapy

Antibody-drug conjugates (ADC) are an inevitable trend in the development of modern "precision medicine". The goal of this work is to produce enzyme-responsive antibody nanoparticle-loaded medication (FMSN-Dox-H2-AE01) based on the EGFR antibody (AE01) and human serum albumin (HSA) shelled mesoporous silica nanoparticles. HSA and antibodies on the surface of the particlescan not only enhance the biocompatibility of the particle and avoid early drug leakage but also allow selective biodegradation triggered by matrix metalloproteinase-2 (MMP-2), which are overexpressed enzymes in some tumor tissues. The cytotoxicity test confirmed favorable safety and efficacy of the ADC. The mortality rate of cancer cells is about 85-90%. Moreover, the antibody nanoparticle-loaded drug showed distinguishing controlled release efficiency toward cancer cells induced by different levels of MMP-2 and pH. This enzyme-responsive FMSN-Dox-H2-AE01 offers a promising option for cancer therapy.

Albumin-binding photosensitizer capable of targeting glioma via the SPARC pathway

BACKGROUND

Malignant glioma is among the most lethal and frequently occurring brain tumors, and the average survival period is 15 months. Existing chemotherapy has low tolerance and low blood-brain barrier (BBB) permeability; therefore, the required drug dose cannot be accurately delivered to the tumor site, resulting in an insufficient drug effect.

METHODS

Herein, we demonstrate a precision photodynamic tumor therapy using a photosensitizer (ZnPcS) capable of binding to albumin in situ, which can increase the permeability of the BBB and accurately target glioma. Albumin-binding ZnPcS was designed to pass through the BBB and bind to secreted protein acidic and rich in cysteine (SPARC), which is abundant in the glioma plasma membrane.

RESULTS

When the upper part of a mouse brain was irradiated using a laser (0.2 W cm^- 2) after transplantation of glioma and injection of ZnPcS, tumor growth was inhibited by approximately 83.6%, and the 50% survival rate of the treatment group increased by 14 days compared to the control group. In glioma with knockout SPARC, the amount of ZnPcS entering the glioma was reduced by 63.1%, indicating that it can target glioma through the SPARC pathway.

CONCLUSION

This study showed that the use of albumin-binding photosensitizers is promising for the treatment of malignant gliomas.

Polydopamine nanoparticles coated with a metal-polyphenol network for enhanced photothermal/chemodynamic cancer combination therapy

Polydopamine nanoparticles (PDA NPs) are commonly used for photothermal therapy (PTT) of cancer because of their good biocompatibility and photothermal conversion capability. However, it is difficult to achieve a good tumor inhibition effect with a single PTT of PDA. Therefore, in this work, we prepared a combined anticancer nanosystem for enhanced chemodynamic therapy (CDT)/PTT by coating PDAs with an (-)-epigallocatechin gallate (EGCG)/iron (Fe) metal-polyphenol network (MPN). The MPN shell of this nanosystem named EGCG@PDA is degraded by the weakly acidic environment intracellular, releasing EGCG and Fe³⁺. EGCG inhibits the expression of heat shock proteins (HSPs) in cancer cells, thus eliminating their thermal protection against cancer cells for enhanced PTT. Meanwhile, the reductive EGCG can also reduce Fe³⁺ to Fe²⁺, to catalyze the decomposition of overexpressed hydrogen peroxide (H₂O₂) in cancer cells to generate strong oxidative hydroxyl radicals (OH), i.e., catalyzing the Fenton reaction, for CDT. After the Fenton reaction, the re-oxidized Fe ions can be reduced again by EGCG and reused to catalyze the Fenton reaction, which can achieve enhanced CDT. Both in vitro and in vivo studies have shown that EGCG@PDA has low dark toxicity and good anticancer effects. It is expected to be used for precision cancer therapy.

Charge-conversional click polyprodrug nanomedicine for targeted and synergistic cancer therapy

Polyprodrug nanomedicines hold great potential for combating tumors. However, the functionalization of polyprodrug nanomedicines to improve therapeutic efficacy is restricted by conventional polymerization methods. Herein, we fabricated a charge-conversional click polyprodrug nanomedicine system by metal-free azide-alkyne cycloaddition click polymerization (AACCP) for targeted and synergistic cancer therapy. Specifically, Pt(IV) prodrug-backboned diazide monomer, DMC prodrug-pendent diazide monomer, dialkyne-terminated PEG monomer and azide-modified folate were click polymerized to obtain the target polyprodrug (P1). P1 could self-assemble into nano-micelles (1-NM), where PEG was the hydrophilic shell with folate on the surface, Pt(IV) and DMC prodrugs as the hydrophobic core. Taking advantage of PEGylation and folate-mediated tumor cell targeting, 1-NM achieved prolonged blood circulation time and high tumor accumulation efficiency. Tumor acidic microenvironment-responsive cleavage and cascade activation of pendant DMC prodrug induced surface charge conversion of 1-NM from negative to positive, which promoted tumor penetration and cellular internalization of the remaining 1-NM. After internalization into tumor cells, the reduction-responsive activation of Pt(IV) prodrug to Pt(II) further showed synergetic effect with DMC for enhanced apoptosis. This first designed charge-conversional click polyprodrug nanomedicine exhibited targeted and synergistic efficacy to suppress tumor proliferation in living mice bearing human ovarian tumor model.

Metal-polyphenol nanodots loaded hollow MnO2 nanoparticles with a "dynamic protection" property for enhanced cancer chemodynamic therapy

Chemodynamic therapy (CDT) is a novel cancer therapeutic strategy. However, barriers such as high glutathione (GSH) concentration and low concentration of metal ions intracellular reduce its treatment effect. In this work, a nanosystem named GA-Fe@HMDN-PEI-PEG with a "dynamic protection" property was reported for enhanced cancer CDT. Mesoporous hollow manganese dioxide (MnO₂) nanoparticle (HMDN) was prepared to load gallic acid-ferrous (GA-Fe) nanodots fabricated from gallic acid (GA) and ferrous ion (Fe²⁺). Then the pores of HMDN were blocked by polyethyleneimine (PEI), which was then grafted with methoxy poly(ethylene glycol) (mPEG) through a pH-sensitive benzoic imine bond. mPEG could protect the nanoparticles (NPs) against the nonspecific uptake by normal cells and enhance their accumulation in the tumor. However, in the slightly acidic tumor microenvironment, hydrolysis of benzoic imine led to DePEGylation to reveal PEI for enhanced uptake by cancer cells. The reaction between HMDN and GSH could consume GSH and obtain manganese ion (Mn²⁺) for the Fenton-like reaction for CDT. GA-Fe nanodots could also offer Fe for the Fenton reaction, and reductive GA could reduce the high-valence ions to low-valence for reusing in Fenton and Fenton-like reactions. These properties allowed GA-Fe@HMDN-PEI-PEG for precise medicine with a high utilization rate and common side effects.

Simultaneous Knockdown of Immune Suppressive Markers by Tumor Microenvironment-Responsive Multifaceted Prodrug Nanomedicine

Tumors managing to exempt from immune clearance are attributable to their overexpressed immune suppressive molecules (CD47, PD-L1, etc.). Leadingly, the checkpoint blockade-based chemoimmunotherapy by means of knockdown of these immunosuppressive checkpoints, together with immunogenetic chemotherapeutics, is perceived to be a valid therapeutic strategy for improving anti-tumor outcomes. Herein, chemotherapeutic camptothecin was covalently introduced into an intriguing multifaceted nanomedicine. Note that the elaborated nanomedicine was chemically engineered to enable targeted transportation to the tumors via systemic administration, possessing intelligent responsiveness to sequential extracellular and intracellular microenvironments in the targeted tumors for prompted transcellular endocytosis owing to enzymolysis by the tumor-enriched matrix metalloproteinases and the selective liberation of cytocidal camptothecin in the cell interiors owing to thiolysis by glutathione. In addition, this chemotherapeutic nanomedicine allowed facile encapsulation of the negatively charged RNA interference payloads. Consequently, aiming for treatment of intractable triple-negative breast tumors, we attempted the small interfering RNA (siRNA) payloads aiming for CD47 and PD-L1 into the aforementioned nanomedicine. The subsequent investigations demonstrated drastic knockdown of these vital immune suppressive checkpoints by this siRNA-encapsulating chemotherapeutic nanomedicine, conducing to the reversal of the immune checkpoint suppressive microenvironment of triple-negative 4T1 tumors. Namely, the inhibited proceedings of the innate and adaptive anti-tumor immunities were revived, as supported by observation of the activated infiltration and retention of CD68⁺ macrophages and CD4⁺ and CD8⁺ lymphocytes into the tumors. Eventually, most potent anti-tumor efficacies were accomplished by systemic administration of this chemoimmunotherapeutic nanomedicine, which verified the amplified contribution from anti-tumor immunities by means of knockdown of the immune suppressive molecules to the ultimate anti-tumor efficacies. Note that the upregulation of the immune suppressive molecules was constantly reported in a variety of clinical therapies; hence, our facile chemoimmunotherapeutic platform should be emphasized in clinical translation for seeking improved therapeutic outcomes.

Catalytic nanotechnology of X-ray photodynamics for cancer treatments

Photodynamic therapy (PDT) has been applied in cancer treatment because of its high selectivity, low toxicity, and non-invasiveness. However, the limited penetration depth of the light still hampers from reaching deep-seated tumors. Considering the penetrating ability of high-energy radiotherapy, X-ray-induced photodynamic therapy (X-PDT) has evolved as an alternative to overcome tissue blocks. As the basic principle of X-PDT, X-rays stimulate the nanoparticles to emit scintillating or persistent luminescence and further activate the photosensitizers to generate reactive oxygen species (ROS), which would cause a series of molecular and cellular damages, immune response, and eventually break down the tumor tissue. In recent years, catalytic nanosystems with unique structures and functions have emerged that can enhance X-PDT therapeutic effects via an immune response. The anti-cancer effect of X-PDT is closely related to the following factors: energy conversion efficiency of the material, the radiation dose of X-rays, quantum yield of the material, tumor resistance, and biocompatibility. Based on the latest research in this field and the classical theories of nanoscience, this paper systematically elucidates the current development of the X-PDT and related immunotherapy, and highlights its broad prospects in medical applications, discussing the connection between fundamental science and clinical translation.

Role of LGMN in tumor development and its progression and connection with the tumor microenvironment

Legumain (LGMN) has been demonstrated to be overexpressed not just in breast, prostatic, and liver tumor cells, but also in the macrophages that compose the tumor microenvironment. This supports the idea that LGMN is a pivotal protein in regulating tumor development, invasion, and dissemination. Targeting LGMN with siRNA or chemotherapeutic medicines and peptides can suppress cancer cell proliferation in culture and reduce tumor growth in vivo. Furthermore, legumain can be used as a marker for cancer detection and targeting due to its expression being significantly lower in normal cells compared to tumors or tumor-associated macrophages (TAMs). Tumor formation is influenced by aberrant expression of proteins and alterations in cellular architecture, but the tumor microenvironment is a crucial deciding factor. Legumain (LGMN) is an in vivo-active cysteine protease that catalyzes the degradation of numerous proteins. Its precise biological mechanism encompasses a number of routes, including effects on tumor-associated macrophage and neovascular endothelium in the tumor microenvironment. The purpose of this work is to establish a rationale for thoroughly investigating the function of LGMN in the tumor microenvironment and discovering novel tumor early diagnosis markers and therapeutic targets by reviewing the function of LGMN in tumor genesis and progression and its relationship with tumor milieu.

Programmable multistage small-molecule nano-photosensitizer for multimodal imaging-guided photothermal therapy

Photothermal therapy has become a promising approach as precision medicine to allow spatial control of therapeutic effect only in the site of interest. However, the full potential of PTT has not been realized due to the lack of simple photosensitizers (PSs) that can overcome multistage biological barriers and improve theranostic efficiency. Here, we develop a small molecule-based PS to enhance tumor-specific PTT by programming multistage transport and activation properties in molecular architecture. This PS can self-assemble into stable nanoparticles that accumulate passively in tumor, and then actively internalize through ligand-mediated endocytosis. Subsequently, the programmable degradable linkers are selectively cleaved, enabling size shrinkage for better tumor penetration, binding albumin to enhance the near-infrared fluorescence for low-background imaging, and activating photothermal conversion for tumor suppression. The self-delivery process can be programmed, representing the first multistage small-molecule nano-photosensitizer that overcomes multiple biological barriers and improves the PTT index of tumor. STATEMENT OF SIGNIFICANCE: Photothermal therapy has become a promising approach as precision medicine, but has not been realized due to the lack of simple photosensitizers that can overcome multistage biological barriers and improve theranostic efficiency. In this contribution, we solve this dilemma by developing a small molecule-based photosensitizer by programming multistage transport and activation properties in molecular architecture, which could self-assemble into stable nanoparticles that accumulate passively in tumor, and actively internalized through ligand-mediated endocytosis. Subsequently, the programmable activation by ROS triggered size reduction for tumor penetration and minimized the phototoxicity to normal tissue. The activatable fluorescence and photothermal properties made the photosensitizer intrinsically suitable for multimodal imaging-guided PTT, providing a promising supramolecular nanomedicine towards tumor precise diagnosis and therapy.

Nanoprobe Based on Biominerals in Protein Corona for Dual-Modality MR Imaging and Therapy of Tumors

Various functional nanomaterials have been fabricated as diagnostic and therapeutic nanomedicines; however, the nanoparticles closely interact with proteins when immersed in biological fluids, forming a "protein corona" that critically alters the biological identity of nanomedicine. Here, we developed a robust strategy to construct theranostic nanoprobes based on protein-corona-coated Fe₃O₄ nanoparticles and biomineralization in the corona. Water-soluble carboxylic Fe₃O₄ nanoparticles were prepared by treating oleate-capped Fe₃O₄ nanoparticles with Lemieux-von Rudloff reagent. Bovine serum albumin (BSA) was used as a model protein to form a corona on the surface of Fe₃O₄ nanoparticles, endowing the Fe₃O₄ nanoparticles with biocompatibility and nonimmunogenicity. The protein corona also provides a template for biomimetic mineralization of Fe³⁺ with tannic acid (TA) to construct Fe₃O₄@BSA-TAFe^III nanoprobes. The TA-Fe(III) biominerals can not only act as photothermal therapy agents but also interact with unsaturated transferrin in plasma to form a "hybrid" corona, enabling the nanoprobes to target tumor cells through the mediation of transferrin receptors, which commonly overexpress on tumor cell membranes. Once taken in by tumor cells, the protonation of phenol hydroxyl groups in acidic lysosomes would lead to the release of Fe³⁺, inducing tumor cell death through a ferroptosis/apoptosis hybrid pathway. In addition, the released Fe³⁺ can boost the T₁-weighted MR imaging performance, and the Fe₃O₄ nanoparticles serve as T₂-weighted MR imaging contrast agents. It is thus believed that the current nanoprobes can realize the enhanced dual-modality MR imaging and combined therapy of tumors through controlling the protein corona and biomineralization.

Tumor-Specific NIR-Activatable Nanoreactor for Self-Enhanced Multimodal Imaging and Cancer Phototherapy

Responsive nanosystems for tumor treatment with high specificity and sensitivity have aroused great attention. Herein, we develop a tumor microenvironment responsive and near-infrared (NIR)-activatable theranostic nanoreactor for imaging-guided anticancer therapy. The nanoreactor (SnO2-x@AGP) is comprised of poly(vinylpyrrolidine) encapsulated hollow mesoporous black SnO2-x nanoparticles coloaded with glucose oxidase (GOx) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The constructed nanoreactor can be specifically activated through endogenous H2O2 by an NIR-mediated "bursting-like" process to enhance its imaging and therapeutic functions. Black SnO2-x with abundant oxygen vacancies expedites effective separation of electron-hole pairs from energy-band structure and endows them with strong hyperthermia effect upon NIR laser irradiation. The generating toxic H2O2 with the assistance of GOx provides SnO2-x@AGP with the capacity of oxidative stress therapy. Ascended H2O2 can activate ABTS into ABTS•+. ABTS•+ not only possesses significant NIR absorption properties, but also disrupts intracellular glutathione to generate excessive reactive oxygen species for improved phototherapy, leading to more effective treatment together with oxidative stress therapy. Thus, SnO2-x@AGP with NIR-mediated and H2O2-activated performance presents tumor inhibition efficacy with minimized damage to normal tissues. These outstanding characteristics of SnO2-x@AGP bring an insight into the development of activatable nanoreactors for smart, precise, and non-invasive cancer theranostics.