Tumor Microenvironment-Adaptive Nanoplatform Synergistically Enhances Cascaded Chemodynamic Therapy

Turning foes to friends: Advanced "in situ nanovaccine" with dual immunoregulation for enhanced immunotherapy of metastatic triple-negative breast cancer

As a "cold tumor", triple-negative breast cancer (TNBC) exhibits limited responsiveness to current immunotherapy. How to enhance the immunogenicity and reverse the immunosuppressive microenvironment of TNBC remain a formidable challenge. Herein, an "in situ nanovaccine" Au/CuNDs-R848 was designed for imaging-guided photothermal therapy (PTT)/chemodynamic therapy (CDT) synergistic therapy to trigger dual immunoregulatory effects on TNBC. On the one hand, Au/CuNDs-R848 served as a promising photothermal agent and nanozyme, achieving PTT and photothermal-enhanced CDT against the primary tumor of TNBC. Meanwhile, the released antigens and damage-associated molecular patterns (DAMPs) promoted the maturation of dendritic cells (DCs) and facilitated the infiltration of T lymphocytes. Thus, Au/CuNDs-R848 played a role as an "in situ nanovaccine" to enhance the immunogenicity of TNBC by inducing immunogenic cell death (ICD). On the other hand, the nanovaccine suppressed the myeloid-derived suppressor cells (MDSCs), thereby reversing the immunosuppressive microenvironment. Through the dual immunoregulation, "cold tumor" was transformed into a "hot tumor", not only implementing a "turning foes to friends" therapeutic strategy but also enhancing immunotherapy against metastatic TNBC. Furthermore, Au/CuNDs-R848 acted as an excellent nanoprobe, enabling high-resolution near-infrared fluorescence and computed tomography imaging for precise visualization of TNBC. This feature offers potential applications in clinical cancer detection and surgical guidance. Collectively, this work provides an effective strategy for enhancing immune response and offers novel insights into the potential clinical applications for tumor immunotherapy.

Platelet Membrane Coated Cu9S8-SNAP for Targeting NIR-II Mild Photothermal Enhanced Chemodynamic/Gas Therapy of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a highly aggressive and uncommon subtype of breast cancer with a poor prognosis. It is crucial to prioritise the creation of a nanotherapeutic method that is highly selective and actively targeting TNBC. This study explores a new nanosystem, Cu9S8-SNAP@PM (C-S@P), composed of Cu9S8-SNAP coated with a platelet membrane (PM). The purpose of this nanosystem is to cure TNBC using multimodal therapy. The utilisation of PM-coated nanoparticles (NPs) enables active targeting, leading to the efficient accumulation of C-S@P within the tumour. The Cu9S8 component within these NPs serves the potential to exert photothermal therapy (PTT) and chemodynamic therapy (CDT). Simultaneously, the S-Nitroso-N-Acetylvanicillamine (SNAP) component enables nitric oxide (NO) gas therapy (GT). Furthermore, when exposed to NIR-II laser light, Cu9S8 not only increases the temperature of the tumour area for PTT, but also boosts CDT and stimulates the release of NO through thermal reactions to improve the effectiveness of GT. Both in vitro and in vivo experimental results validate that C-S@P exhibits minimal side effects and represents a multifunctional nano-drug targeted at tumors for efficient treatment. This approach promises significant potential for TNBC therapy and broader applications in oncology.

Sensitize Tumor Immunotherapy: Immunogenic Cell Death Inducing Nanosystems

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

Strategies and Recent Advances on Improving Efficient Antitumor of Lenvatinib Based on Nanoparticle Delivery System

Lenvatinib (LVN) is a potentially effective multiple-targeted receptor tyrosine kinase inhibitor approved for treating hepatocellular carcinoma, metastatic renal cell carcinoma and thyroid cancer. Nonetheless, poor pharmacokinetic properties including poor water solubility and rapid metabolic, complex tumor microenvironment, and drug resistance have impeded its satisfactory therapeutic efficacy. This article comprehensively reviews the uses of nanotechnology in LVN to improve antitumor effects. With the characteristic of high modifiability and loading capacity of the nano-drug delivery system, an active targeting approach, controllable drug release, and biomimetic strategies have been devised to deliver LVN to target tumors in sequence, compensating for the lack of passive targeting. The existing applications and advances of LVN in improving therapeutic efficacy include improving longer-term efficiency, achieving higher efficiency, combination therapy, tracking and diagnosing application and reducing toxicity. Therefore, using multiple strategies combined with photothermal, photodynamic, and immunoregulatory therapies potentially overcomes multi-drug resistance, regulates unfavorable tumor microenvironment, and yields higher synergistic antitumor effects. In brief, the nano-LVN delivery system has brought light to the war against cancer while at the same time improving the antitumor effect. More intelligent and multifunctional nanoparticles should be investigated and further converted into clinical applications in the future.

The H2O2 Self-Sufficient 3D Printed β-TCP Scaffolds with Synergistic Anti-Tumor Effect and Reinforced Osseointegration

Tumor recurrence and massive bone defects are two critical challenges for postoperative treatment of oral and maxillofacial tumor, posing serious threats to the health of patients. Herein, in order to eliminate residual tumor cells and promote osteogenesis simultaneously, the hydrogen peroxide (H2O2) self-sufficient TCP-PDA-CaO2-CeO2 (TPCC) scaffolds are designed by preparing CaO2 or/and CeO2 nanoparticles (NPs)/chitosan solution and modifying the NPs into polydopamine (PDA)-modified 3D printed TCP scaffolds by rotary coating method. CaO2 NPs loaded on the scaffolds can release Ca2+ and sufficient H2O2 in the acidic tumor microenvironment (TME). The generated H2O2 can further produce hydroxyl radicals (·OH) under catalysis effect by peroxidase (POD) activity of CeO2 NPs, in which the photothermal effect of the PDA coating enhances its POD catalytic effect. Overall, NPs loaded on the scaffold chemically achieve a cascade reaction of H2O2 self-sufficiency and ·OH production, while functionally achieving synergistic effects on anti-tumor and bone promotion. In vitro and in vivo studies show that the scaffolds exhibit effective osteo-inductivity, induced osteoblast differentiation and promote osseointegration. Therefore, the multifunctional composite scaffolds not only validate the concept of chemo-dynamic therapy (CDT) cascade therapy, but also provide a promising clinical strategy for postoperative treatment of oral and maxillofacial tumor.

Seeking Cells, Targeting Bacteria: A Cascade-Targeting Bacteria-Responsive Nanosystem for Combating Intracellular Bacterial Infections

Intracellular bacteria pose a great challenge to antimicrobial therapy due to various physiological barriers at both cellular and bacterial levels, which impede drug penetration and intracellular targeting, thereby fostering antibiotic resistance and yielding suboptimal treatment outcomes. Herein, a cascade-target bacterial-responsive drug delivery nanosystem, MM@SPE NPs, comprising a macrophage membrane (MM) shell and a core of SPE NPs. SPE NPs consist of phenylboronic acid-grafted dendritic mesoporous silica nanoparticles (SP NPs) encapsulated with epigallocatechin-3-gallate (EGCG), a non-antibiotic antibacterial component, via pH-sensitive boronic ester bonds are introduced. Upon administration, MM@SPE NPs actively home in on infected macrophages due to the homologous targeting properties of the MM shell, which is subsequently disrupted during cellular endocytosis. Within the cellular environment, SPE NPs expose and spontaneously accumulate around intracellular bacteria through their bacteria-targeting phenylboronic acid groups. The acidic bacterial microenvironment further triggers the breakage of boronic ester bonds between SP NPs and EGCG, allowing the bacterial-responsive release of EGCG for localized intracellular antibacterial effects. The efficacy of MM@SPE NPs in precisely eliminating intracellular bacteria is validated in two rat models of intracellular bacterial infections. This cascade-targeting responsive system offers new solutions for treating intracellular bacterial infections while minimizing the risk of drug resistance.

Mg-ZIF nanozymes disrupt the level of ROS for osteosarcoma killing via POD activity

Osteosarcoma (OS) is notorious for its high malignancy, and conventional chemotherapy drugs, while killing tumor cells, often inflict significant harm on the patient's body. The tumor microenvironment of OS is characterized by high levels of hydrogen peroxide (H2O2). Leveraging this feature, we have developed Mg-ZIF nanoparticles, which incorporate magnesium (Mg) to confer robust peroxidase (POD)-like enzymatic activity. These Mg-ZIF nanozymes can generate highly lethal superoxide anions within tumor cells in a responsive manner, thereby achieving effective tumor destruction. Both in vitro and in situ OS models have corroborated the anti-tumor efficacy of Mg-ZIF nanozymes, while also validating their biosafety. The design of Mg-ZIF nanozymes opens a new avenue for the treatment of OS, offering a promising therapeutic strategy.

An oral bioactive chitosan-decorated doxorubicin nanoparticles/bacteria bioconjugates enhance chemotherapy efficacy in an in-situ breast cancer model

Breast cancer is the second leading cause of cancer-related deaths among women worldwide. Despite significant advancements in chemotherapy, its effectiveness is often limited by poor drug distribution and systemic toxicity caused by the weak targeting ability of conventional therapeutic agents. The hypoxic tumor microenvironment (TME) also plays a vital role in treatment outcomes. Oral anticancer therapeutic agents have gained popularity and show promising results due to their ease of repeated administration. This study introduces autopilot biohybrids (Bif@BDC-NPs) for the effective delivery of doxorubicin (DOX) to the tumor site. This hybrid combines albumin-encapsulated DOX nanoparticles (BD-NPs) coated with chitosan (CS) for breast cancer chemotherapy, along with anaerobic Bifidobacterium infantis (B. infantis, Bif) serving as self-propelled motors. Due to Bif's specific anaerobic properties, Bif@BDC-NPs precisely anchor hypoxic regions of tumor tissue and significantly increase drug accumulation at the tumor site, thereby promoting tumor cell death. In an in-situ mouse breast cancer model, Bif@BDC-NPs achieved 94 % tumor inhibition, significantly prolonging the median survival of mice to 62 days, and reducing the toxic side effects of DOX. Therefore, the new bacteria-driven oral drug delivery system, Bif@BDC-NPs, overcomes multiple physiological barriers and holds great potential for the precise treatment of solid tumors.

Tumor microenvironment reprogramming by nanomedicine to enhance the effect of tumor immunotherapy

With the rapid development of the fields of tumor biology and immunology, tumor immunotherapy has been used in clinical practice and has demonstrated significant therapeutic potential, particularly for treating tumors that do not respond to standard treatment options. Despite its advances, immunotherapy still has limitations, such as poor clinical response rates and differences in individual patient responses, largely because tumor tissues have strong immunosuppressive microenvironments. Many tumors have a tumor microenvironment (TME) that is characterized by hypoxia, low pH, and substantial numbers of immunosuppressive cells, and these are the main factors limiting the efficacy of antitumor immunotherapy. The TME is crucial to the occurrence, growth, and metastasis of tumors. Therefore, numerous studies have been devoted to improving the effects of immunotherapy by remodeling the TME. Effective regulation of the TME and reversal of immunosuppressive conditions are effective strategies for improving tumor immunotherapy. The use of multidrug combinations to improve the TME is an efficient way to enhance antitumor immune efficacy. However, the inability to effectively target drugs decreases therapeutic effects and causes toxic side effects. Nanodrug delivery carriers have the advantageous ability to enhance drug bioavailability and improve drug targeting. Importantly, they can also regulate the TME and deliver large or small therapeutic molecules to decrease the inhibitory effect of the TME on immune cells. Therefore, nanomedicine has great potential for reprogramming immunosuppressive microenvironments and represents a new immunotherapeutic strategy. Therefore, this article reviews strategies for improving the TME and summarizes research on synergistic nanomedicine approaches that enhance the efficacy of tumor immunotherapy.

Orchestrating Precision within the Tumor Microenvironment by Biomimetic Nanoprodrugs for Effective Tumor Therapy

Malignant tumors are still one of the most deadly diseases that threaten human life and health. However, developing new drugs is challenging due to lengthy trials, funding constraints, and regulatory approval procedures. Consequently, researchers have devoted themselves to transforming some clinically approved old drugs into antitumor drugs with certain active ingredients, which have become an attractive alternative. Disulfiram (DSF), an antialcohol medication, can rapidly metabolize in the physiological environment into diethyldithiocarbamate (DTC) which can readily react with Cu2+ ions in situ to form the highly toxic bis(N,N-diethyldithiocarbamate)-copper(II) (CuET) complex. In this study, DSF is loaded into mesoporous dopamine nanocarriers and surface-chelated with tannin and Cu2+ to construct M-MDTC nanoprodrugs under the camouflage of K7 tumor cell membranes. After intravenous injection, M-MDTC nanoprodrugs successfully reach the tumor sites with the help of mediated cell membranes. Under slightly acidic pH and photothermal stimulation conditions, DSF and Cu2+ are simultaneously released, forming a highly toxic CuET to kill tumor cells in situ. The generated CuET can also induce immunogenic cell death of tumor cells, increase the proportion of CD86+ CD80+ cells, and promote dendritic cell maturation. In vitro and in vivo studies of M-MDTC nanoprodrugs have shown excellent tumor-cell-killing ability and solid tumor suppression. This approach enables in situ amplification of chemotherapy in the tumor microenvironment, achieving an effective antitumor treatment.

Cancer Cell Membrane-Based Materials for Biomedical Applications

The nanodelivery system provides a novel direction for disease diagnosis and treatment; however, its delivery effectiveness is restricted by the short biological half-life and inadequate tumor targeting. The immune evasion properties and homologous targeting capabilities of natural cell membranes, particularly those of cancer cell membranes (CCM), have gained significant interest. The integration of CCM and nanoparticles has resulted in the emergence of CCM-based nanoplatforms (CCM-NPs), which have gained significant attention due to their unique properties. CCM-NPs not only prolong the blood circulation time of core nanoparticles, but also direct them for homologous tumor targeting. Herein, the history and development of CCM-NPs as well as how these platforms have been used for biomedical applications are discussed. The application of CCM-NPs for cancer therapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CCM-NPs.

Synergistic reinforcement of immunogenic cell death and transformation of tumor-associated macrophages via an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform

The immune system's role in tumor growth and spread has led to the importance of activating immune function in tumor therapy. We present a strategy using an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform (M1mDDTF) to synergistically reinforce immunogenic cell death (ICD) and transform tumor-associated macrophages (TAMs) against tumors. The M1mDDTF nanoparticles consist of doxorubicin-loaded dendritic mesoporous silica nanoparticles chelated with FeIII-tannic acid (FeIIITA) and coated with M1-type macrophage membranes. In the acidic tumor microenvironment, FeIIITA releases Fe2+ and generates ·OH, aided by near infrared irradiation for enhanced doxorubicin release. Furthermore, the M1mDDTF nanoplatform not only directly kills tumor cells but stimulates ICD, which can increase the proportion of CD86+ CD80+ cells and promote dendritic cell maturation. Particularly, the M1mDDTF nanoplatform can also promote the gradual polarization of TAMs into the M1-type and promote tumor cell killing. This study demonstrates the safety and multifunctionality of M1mDDTF nanoparticles, highlighting their potential for clinical tumor treatment. STATEMENT OF SIGNIFICANCE: Malignant tumors are a global concern and a major cause of death. Nanoparticles' passive targeting is ineffective and hindered by reticuloendothelial system clearance. Therefore, enhancing nanoparticle accumulation in tumors while minimizing toxicity is a challenge. Coating nanoparticles with cell membranes enhances biocompatibility, immune evasion, and specific targeting. This approach has led to the development of numerous cell membrane-mimicking nanomaterials with remarkable properties and functions. This study developed an M1-type macrophage membrane-camouflaged ferrous-supply-regeneration nanoplatform, boosting immunogenic cell death and transforming tumor-associated macrophages. Tannic acid in the tumor microenvironment reduced Fe3+ to Fe2+, generating ·OH. M1mDDTF nanosystem induced M1-type macrophage polarization, inhibiting tumor growth and triggering immune cell death. Safe and versatile, these M1mDDTF nanoparticles hold promise for clinical tumor treatment.

Au Nanorods Activated the Zn/Ce Composites with Cancer Cell Specific Cytotoxicity for Enhanced Chemodynamic Therapy

Chemodynamic therapy based on the Fenton reaction has been developed as an extremely promising modality for cancer therapeutics. In this study, a core-shell structure nanoplatform was constructed by a Au nanorod externally encapsulating Ce/Zn-based composites (ACZO). The nanoparticles can catalyze the generation of reactive oxygen species (ROS) under acidic conditions and effectively consume existing glutathione (GSH) to destroy the redox balance within the tumor. Moreover, the decomposition of the nanocomplexes under acidic conditions releases large amounts of zinc ions, leading to zinc overload in cancer cells. The photothermal effect generated by the Au nanorods not only provides photothermal therapy (PTT) but also augments the catalytic reaction and ions action mentioned above. This facile strategy to improve the efficacy of chemodynamic therapy by the photothermal enhancement of catalytic activity and zinc ion release provides a promising perspective for potential tumor treatment.

Advent in proteins, nucleic acids, and biological cell membranes functionalized nanocarriers to accomplish active or homologous tumor targeting for smart amalgamated chemotherapy/photo-therapy: A review

Conventional cancer mono-therapeutic approaches including radiotherapy, surgery, and chemotherapy don't always achieve satisfactory outcomes and are frequently associated with significant limitations. Although chemotherapy is a vital intervention, its effectiveness is frequently inadequate and is associated with metastasis, multidrug resistance, off-target effect, and normal cells toxicity. Phototherapies are employed in cancer therapy, encompassing photo-dynamic and photo-thermal therapies which under favorable NIR laser light irradiation initiate the included photosensitizers and photo-thermal agents to generate ROS or thermal heat respectively for cancer cells destruction. Photo-therapy is considered noninvasive, posing no resistance, but it still suffers from several pitfalls like low penetration depth and excessive heat generation affecting neighboring tissues. Improved selectivity and tumor-homing capacity could be attained through surface modulation of nanoparticles with targeting ligands that bind to receptors, which are exclusively overexpressed on cancerous cells. Developing novel modified targeted nanoparticulate platforms integrating different therapeutic modalities like photo-therapy and chemotherapy is a topic of active research. This review aimed to highlight recent advances in proteins, nucleic acids, and biological cell membranes functionalized nanocarriers for smart combinatorial chemotherapy/photo-therapy. Nanocarriers decorated with precise targeting ligands, like aptamers, antibody, and lactoferrin, to achieve active tumor-targeting or camouflaging using various biological cell membrane coating are designed to achieve homologous tumor-targeting.

Novel PdPtCu Nanozymes for Reprogramming Tumor Microenvironment to Boost Immunotherapy Through Endoplasmic Reticulum Stress and Blocking IDO-Mediated Immune Escape

Breaking immunosuppressive tumor microenvironment (TME) has unique effects on inhibiting tumor growth and recurrence. Here, an endoplasmic reticulum (ER) targeted PdPtCu nanozyme (PNBCTER ) is prepared to boost immunotherapy. First, PNBCTER has three kinds of enzyme activities, including catalase (CAT), glutathione oxidase (GSHOx), and peroxidase (POD)-like activities, which can reshape the TME. Second, PNBCTER kills tumor cells by photodynamic therapy (PDT) and photothermal therapy (PTT). Third, guided by TER , PNBCTER not only realizes the combination therapy of PDT, PTT and chemodynamic therapy (CDT), but also damages the ER of tumor cells and actives antitumor immune response, which breaks through the immune blockade of TME. Finally, the NLG919 blocks the tryptophan/kynurenine immune escape pathway and reverses the immunosuppressive TME. The strategy that reshaping the TME by enzyme catalysis and breaking immunosuppression provides a novel way for the application of combination therapy in tumor.

Plasmonic nanobipyramids with photo-enhanced catalytic activity under near-infrared II window for effective treatment of breast cancer

Nanozyme-based catalytic therapy is an effective method for cancer treatment, but insufficient catalytic activity presents a challenge in achieving optimal therapeutic outcomes. External light can provide an innovative approach to modulate nanozyme catalytic activity. Herein, we report on plasmonic gold nanobipyramid@cuprous oxide (Au NBP@Cu2O) nanozyme for the effective phototherapy of breast cancer. In the tumor microenvironment, Cu+-mediated Fenton-like reaction catalyzes the generation of toxic hydroxyl radicals (•OH) from endogenous hydrogen peroxide to induce apoptosis. Additionally, the Au NBP@Cu2O nanostructure improves the absorption performance of Au NBPs in the near-infrared II region through near-field enhancement of equipartite exciters and achieves a high photothermal conversion efficiency value of 58%. Remarkably, the Au NBP@Cu2O nanoheterostructure can capture hot electrons induced by equipartition excitations and promote electron-hole separation under 1064 nm laser irradiation, facilitating the production of more reactive oxygen species (ROS). The mechanism behind this enhanced catalytic activity was unraveled using femtosecond transient absorption spectroscopy. Both in vitro and in vivo investigations have demonstrated the efficacious tumor therapeutic potential of Au NBP@Cu2O nanozyme, particularly under 1064 nm laser irradiation. Furthermore, the proposed therapeutic approach has been proved to effectively block tumor metastasis, providing a promising strategy for the development of multifunctional nanotherapeutics to tackle metastatic tumors. STATEMENT OF SIGNIFICANCE: A highly effective plasmonic nanozyme has been developed to improve catalytic therapy for breast cancer. When exposed to 1064 nm laser irradiation, Au NBP@Cu2O nanozyme can promote the separation of hot electrons and holes thereby facilitating the production of reactive oxygen species. Hot electrons transfer behavior is unveiled by femtosecond transient absorption spectroscopy technique. This enhanced catalytic activity, along with the intrinsic photothermal effect, effectively kills tumor cells.

Bimetallic Ions Functionalized Metal-Organic-Framework Nanozyme for Tumor Microenvironment Regulating and Enhanced Photodynamic Therapy for Hypoxic Tumor

Photodynamic therapy (PDT), as a light irradiation inducing reactive oxygen species (ROS) generation for cancer treatment, offers facile and promising solutions with respect to spatiotemporal control of ROS generation, and minimizes the systemic toxicity and side effects for highly precise tumor therapy. However, the PDT efficiency is often severely compromised by the complex tumor microenvironment (TME), such as the hypoxic condition and overexpressed antioxidants. Here, for the first time, a bimetallic ion-modified metal-organic framework nanozyme (Zr4+ -MOF-Ru3+ /Pt4+ -Ce6@HA, ZMRPC@HA) is designed. ZMRPC@HA with catalase (CAT) and glutathione oxidase (GSHOx) mimetic activities, can efficiently regulate TME by generation of O2 and deplete the GSH synergistically for enhancing the long-term PDT efficacy toward the hypoxic tumor. The in vitro cell inhibition and in vivo on tumor xenograft evaluations demonstrate the PDT strategy by using ZMRPC@HA can successfully inhibit the differentiation and proliferation of tumor cells under a 660 nm laser irradiation in deep tissues. These findings open a new avenue for the design of multimetallic ions functionalized MOF-based nanozymes with multienzyme mimetic activities toward the antitumor and various other biological applications.

Cancer cell membrane-coated upconversion nanoparticles/ZnxMn1-xS core-shell nanoparticles for targeted photodynamic and chemodynamic therapy of pancreatic cancer

Oxidative stress induced by reactive oxygen species (ROS) is promising treatment approach for pancreatic ductal adenocarcinoma (PDAC), which is typically insensitive to conventional chemotherapy. In this study, BxPC-3 pancreatic cancer cell membrane-coated upconversion nanoparticles/ZnxMn1-xS core-shell nanoparticles (abbreviated as BUC@ZMS) were developed for tumor-targeted cancer therapy via synergistically oxidative stress and overcoming glutathione (GSH) overexpression. Using a combination of photodynamic therapy (PDT) and chemodynamic therapy (CDT), the BUC@ZMS core-shell nanoparticles were able to elicit the death of pancreatic cancer cells through the high production of ROS. Additionally, the BUC@ZMS core-shell nanoparticles could deplete intracellular GSH and increase the sensitivity of tumor cells to oxidative stress. The in vivo results indicated that BUC@ZMS nanoparticles can accumulate specifically in tumor locations and suppress PDAC without generating obvious toxicity. Thus, it was determined that the as-prepared core-shell nanoparticles would be a viable treatment option for solid malignancies.

Engineered Enzyme-Loaded Erythrocyte Vesicles Precisely Deprive Tumoral Nutrients to Induce Synergistic Near-Infrared-II Photothermal Therapy and Immune Activation

Starvation therapy has been considered a promising strategy in cancer treatment for altering the tumor microenvironment (TME) and causing a cascade of therapeutic effects. However, it is still highly challenging to establish a therapeutic strategy for precisely and potently depriving tumoral nutrition. In this study, a glucose oxidase (GOx) and thrombin-incorporated erythrocyte vesicle (EV) with cyclic (Arg-Gly-Asp) (cRGD) peptide modification, denoted as EV@RGT, were synthesized for precisely depriving tumoral nutrition and sequentially inducing second near-infrared region (NIR-II) photothermal therapy (PTT) and immune activation. The EV@RGT could specifically accumulate at the tumor site and release the enzymes at the acidic TME. The combination of GOx and thrombin exhausts tumoral glucose and blocks the nutrition supply at the same time, resulting in severe energy deficiency and reactive oxygen species (ROS) enrichment within tumor cells. Subsequently, the abundant clotted erythrocytes in tumor vessels present outstanding localized NIR-II PTT for cancer eradication owing to the hemoglobin. Furthermore, the abundant ROS generated by enhanced starvation therapy repolarizes resident macrophages into the antitumor M1 phenotype via a DNA damage-induced STING/NF-κB pathway, ultimately contributing to tumor elimination. Consequently, the engineered EV@RGT demonstrates powerful antitumor efficiency based on precise nutrition deprivation, sequential NIR-II PTT, and immune activation effect. This work provides an effective strategy for the antitumor application of enzyme-based reinforced starvation therapy.

Enhanced biocompatibility of silk sericin/caffeic acid nanoparticles by red blood cell membranes cloaking

Caffeic acid (CA) is an antioxidant phenolic compound that enriched in coffee beans, however, its administration often restrains by the instability and low solubility. Nanoparticle encapsulation is an effective approach to improve the therapeutic activity of CA. For example, silk sericin (SS), a natural biomaterial finds applications in food, cosmetics and biomedical fields, is proved here to be an appropriate encapsulation agent for CA, and a SS/CA composite nanoparticle has been fabricated. To further improve the biocompatibility of SS/CA, a red blood cell membranes (RM) cloaking strategy is adopted. The as-formed SS/CA/RM preserves the antioxidant activity of CA, and shows satisfactory biocompatibility especially under high concentration. Hope this can provide a potential appropriative strategy to adjust the chemical stability of insoluble drugs and to improve their biocompatibility.

Defect-Rich Ni-CoO@PEG Porous Hexagonal Nanosheets: Multi-enzyme and Ultrasound Catalysis for Synergistic Anticancer Treatment

Given the similarity with photocatalysis, sonodynamic therapy (SDT) can be defined as ultrasonic (US) catalysis. Encouraged by the principles of photocatalysis and defect chemistry, defect-rich nickel (Ni)-doped cobaltous oxide (Ni-CoO@PEG) porous hexagonal nanosheets have been synthesized as a sonosensitizer. The doping of Ni decreases the band gap that is testified by density functional theory to increase the US-generated charges. Under US irradiation, Ni-CoO@PEG nanosheets produce ¹O₂ as an active species that is determined by dissolved O₂ and electrons. Moreover, the doping also brings abundant oxygen vacancies (O_V) that not only are in favor of efficient separation of electron-hole but also enhance the interaction toward O₂, boosting ¹O₂ generation. In addition, Ni-CoO@PEG shows robust mimic catalase (CAT) and peroxidase characterization to effectively improve the intratumor O₂ content and oxidation stress. What is more, the nanosheets also possess glucose oxidase activity that can consume glucose to elevate the H₂O₂/acid level and to block the intracellular energy supply. The tandem nanozyme behaviors would further regulate the tumor microenvironment for assisting anticancer treatment. It is noted that Ni-CoO@PEG reveals a novel half-metallic feature endowing great magnetism and magnetic resonance imaging capacity. The above synergistic treatments exhibit outstanding anticancer performance that also evokes antitumor immunity to suppress metastasis and recurrence, efficiently.