Laser-Ignited Lipid Peroxidation Nanoamplifiers for Strengthening Tumor Photodynamic Therapy Through Aggravating Ferroptotic Propagation and Sustainable High Immunogenicity

Galectin-13 reduces membrane localization of SLC7A11 for ferroptosis propagation

The mechanism of ferroptosis propagation is still unclear. Here our results indicate that the cells undergoing ferroptosis secrete Galectin-13, which binds to CD44 and inhibits the plasma membrane localization of SLC7A11 in neighboring cells, thereby accelerating neighboring cell death and promoting ferroptosis propagation. FOXK1 was phosphorylated by PKCβII and then facilitated the expression and secretion of Galectin-13 during ferroptotic cell death. Correlation analysis and functional analysis revealed that ferroptosis propagation ability was a previously unrecognized determinant of ferroptosis sensitivity in human cancer cells. A synthetic Galectin-13 mimetic peptide was shown to strongly enhance the sensitivity of tumors to the imidazole ketone erastin, radiotherapy and immunotherapy by boosting ferroptosis. In particular, cancer stem cells were vulnerable to the combination of Galectin-13 mimetic peptide and ferroptosis inducers. Our study provides new insights into ferroptosis propagation and highlights novel strategies for targeting ferroptosis to treat tumors.

Tumor Microenvironment-Responsive Lipid Peroxidation Amplifier: Harnessing Ferroptosis Resistance to Devastate the Ferroptosis Defense System

Amplification of lipid peroxidation with tumor specificity represents a new avenue to boost ferroptosis-mediated anticancer therapeutics but remains challenging. Herein, we proposed a metal-phenolic-network (MPN)-coated nanohybrid as a tumor microenvironment-responsive lipid peroxidation amplifier, consisting of reactive oxygen species generator MPN, glutathione (GSH) scavenger GSH-P, and glutathione peroxidase 4 (GPX4) mRNA gene silencing sequence. The protective MPN shell of this amplifier can be specifically disintegrated by acidic and adenosine triphosphate (ATP)-rich tumor microenvironments to induce oxidative stress through the dual disruption of redox homeostasis (Fenton-catalytic reactive oxygen species accumulation and GSH depletion). Furthermore, the oxidative stress-induced upregulation of ferroptosis resistance-related apurinic/apyrimidinic endonuclease 1 (APE1) is further ingeniously employed as an amplification element to prompt the release of apurinic/apyrimidinic (AP) site-embedded GPX4 mRNA gene silencing sequence which can downregulate the GPX4 level. Based on tandem depletion of the GSH substrate and gene silencing of GPX4, the ferroptosis defense system of GPX4/GSH can be heavily devastated to enable amplification of lipid peroxidation for effectively and specifically improving ferroptosis efficiency. We expect this strategy can be further expanded to other important regulatory proteins and provide a mechanism study for ferroptosis-mediated therapy.

Glutathione-scavenging natural-derived ferroptotic nano-amplifiers strengthen tumor therapy through aggravating iron overload and lipid peroxidation

Nanomedicine-driven ferroptosis has emerged as a promising tumor treatment strategy through delivering exogenous iron and aggravating the lethal accumulation of lipid peroxides (LPO). However, the compensatory mechanisms of ferroptosis defense systems in cancer cells compromise the therapeutic efficacy and lead to potential side effects. Herein, a highly effective ferroptotic nano-amplifier is designed to synergistically promote ferroptosis via increasing intracellular labile iron, exacerbating lipid peroxidation and overcoming the defense system. Briefly, a natural-derived amphiphilic polymer composing of chondroitin sulfate (CS), arachidonic acid (AA) and a redox-sensitive linker, cystamine (CYS) is constructed to self-assemble as a GSH-responsive nanodrug delivery system for loading bioactive ingredient Polyphyllin I (PPI) and ferric ion (Fe3+). This nanodrug (CSAA/Fe@PPI) can scavenge the aberrant intracellular GSH via CYS linker, accompanied with the degradation of CSAA/Fe@PPI and the release of PPI, AA and Fe3+. On one hand, the intracellular labile iron level is significantly elevated due to the exogenous delivery of Fe3+ and PPI-induced ferritinophagy. On the other hand, ROS burst and the supplement of AA initiate and propagate the lipid peroxidation chain reaction. Meanwhile, the depletion of intracellular GSH suppresses the GPX4 activity, further strengthening the lethal accumulation of LPO. Consequently, the ferroptotic antitumor efficacy is remarkably improved by systemically aggravating iron overload and lipid peroxidation. Therefore, our study presents an effective strategy to improve ferroptosis-based anti-cancer treatment through multiple intervention routes.

Oxygen Nanobubbles Enhance ICG/Fe(III)-Mediated Dual-Modal Therapy To Induce Ferroptosis in Tumor Treatment

Noninvasive therapies such as photodynamic therapy (PDT) and chemodynamic therapy (CDT), which rely on reactive oxygen species (ROS), are gaining attention for their low toxicity. However, single-modal treatments have individual limitations that restrict the therapeutic efficacy. Fe(III) can coordinate with the hydrophilic regions of indocyanine green (ICG) molecules to form the ICG/Fe(III) complex, making it a promising dual-modal agent for combined PDT and CDT. However, coordination with Fe(III) leads to the aggregation quenching of ICG, hindering its application in dual-modal therapy. We innovatively utilize oxygen nanobubbles, prepared solely from water and oxygen, to significantly reverse the aggregation-induced quenching of the ICG/Fe(III) complex, thereby enhancing its stability in aqueous environments. In this system, Fe(III) assembles at the nanobubble interface, coordinating with ICG's hydrophilic regions to form the ICG/Fe(III)-NBs. The oxygen nanobubbles boost PDT efficiency by improving the ICG/Fe(III) complex stability and oxygen content, while Fe(III) achieves CDT by generating hydroxyl radicals (•OH) through the Fenton reaction. This dual-modality treatment significantly disrupts the tumor's redox balance, induces ferroptosis, and demonstrates strong antitumor efficacy, reducing tumor volume to 34% of its initial size in mice. The strategy offers a promising and clinically viable approach to cancer treatment.

Biomimetic Targeted Co-Delivery System Engineered from Genomic Insights for Precision Treatment of Osteosarcoma

The high heterogeneity and severe side effects of chemotherapy are major factors contributing to the failure of osteosarcoma treatment. Herein, a comprehensive genomic analysis is conducted, and identified two prominent characteristics of osteosarcoma: significant cyclin-dependent kinases 4 (CDK4) amplification and homologous recombination repair deficiency. Based on these findings, a co-delivery system loaded with CDK4/6 inhibitors and poly ADP-ribose polymerase (PARP) inhibitors is designed. By employing metal-organic frameworks (MOFs) as carriers, issue of drug insolubility is effectively addressed, while also enabling controlled release in response to the tumor microenvironment. To enhance targeting capability and biocompatibility, the MOFs are further coated with a bio-membrane targeting B7H3. This targeted biomimetic co-delivery system possesses several key features: 1) it can precisely target osteosarcoma with high B7H3 expression; 2) the combination of CDK4/6 inhibitors and PARP inhibitors exhibits synergistic effects, significantly impairing tumor's DNA repair capacity; and 3) the system has the potential for combination with photodynamic therapy, amplifying DNA repair defects to maximize tumor cell eradication. Furthermore, it is observed that this co-delivery system can activate immune microenvironment, increasing CD8+ T cell infiltration and converting osteosarcoma from an immune-cold to an immune-hot tumor. In summary, the co-delivery system is an effective therapeutic strategy and holds promise as a novel approach for osteosarcoma treatment.

Spatiotemporal-controllable ROS-responsive camptothecin nano-bomb for chemo/photo/immunotherapy in triple-negative breast cancer

Chemotherapy is still one of the major approaches in triple-negative breast cancer (TNBC) treatment. The development of new formulations for classic chemotherapeutic drugs remains interests in studies. Camptothecin (CPT) is powerful antitumor agents in TNBC treatment though its clinic applications are limited by its low water solubility and systemic toxicity. To prepare a spatiotemporal controllable CPT nano-formulation, we construct a ROS-responsive self-assembly nanoparticle by combining hydrophobic CPT and hydrophilic 5-floxuridine (FUDR). A ROS-sensitive thioketal (TK) linker is used to prepare CPT-TK-FUDR (CTF). Next, we introduced IR780-based phototherapy to elicit massive ROS regeneration due to the endogenous ROS is not sufficient. IR780 is modified with hyaluronic acid (HA) to prepare HA-modified IR780 (HAIR) for its biocompatibility and tumor targeting ability improvement. CTF and HAIR self-assemble to form an attractive nano-bomb (HAIR/CTF NPs). HA accurately guides the NPs to tumor sites via HA-receptor recognition on tumor cells. After internalization, overexpressed intracellular HAase in tumor cells disassembles the NPs to free the contents. Due to the presence of IR780 molecules, the scheduled irradiation of 808 nm laser induces massive reactive oxygen species (ROS) generation, which further result in the cleavage of TK linker for free drugs release. Additionally, ROS-mediated photodynamic therapy (PDT) and near-infrared laser-mediated photothermal therapy (PTT) synergistically worked to eradicate tumor cells. Then immunogenic cell death (ICD) was evoked by CPT and phototherapy to amplify antitumor immunity, thereby achieving primary and abscopal tumor inhibition. In conclusion, the HAIR/CTF nano-bomb realized spatiotemporal controllable drug release, exciting tumor eradication and attractive anti-metastasis efficacy via combination chemo/photo/immunotherapy, offering a valuable reference for the re-development of classic drug in future clinical practice.

A Robust ROS Generation and Ferroptotic Lipid Modulation Nanosystem for Mutual Reinforcement of Ferroptosis and Cancer Immunotherapy

Ferroptosis initiation is often utilized for synergistic immunotherapy. While, current immunotherapy is limited by an immunosuppressive tumor microenvironment (TME), and ferroptosis is limited by insufficient reactive oxygen species (ROS) and ferroptotic lipids in tumor cells. Here, an arachidonic acid (AA) loaded nanosystem (CTFAP) is developed to mutually reinforce ferroptosis and cancer immunotherapy by augmenting ROS generation and modulating ferroptotic lipids. CTFAP is composed of acid-responsive core calcium peroxide (CaO2) nanoparticles, ferroptotic lipids sponsor AA, tetracarboxylic porphyrin (TCPP) and Fe3+ based metal-organic framework structure, and biocompatible mPEG-DSPE for improved stability. Once endocytosed by tumor cells, CTFAP can release oxygen (O2) and hydrogen peroxide (H2O2) in the acidic TME, facilitating TCPP-based sonodynamic therapy and Fe3+-mediated Fenton-like reactions to generate substantial ROS for cell ferroptosis initiation. The immunogenic cell death (ICD) after ferroptosis promotes interferon γ (IFN-γ) secretion to up-regulate the expression of long-chain family member 4 (ACSL4), cooperating with the released AA from CTFAP to accelerate the accumulation of lipid peroxidation (LPO) and thereby promoting ferroptosis in cancer cells.CTFAP with ultrasound treatment efficiently suppresses tumor growth, has great potential to challenges in cancer immunotherapy.

Porphyrin-engineered nanoscale metal-organic frameworks: enhancing photodynamic therapy and ferroptosis in oncology

Photodynamic therapy and ferroptosis induction have risen as vanguard oncological interventions, distinguished by their precision and ability to target vulnerabilities in cancer cells. Photodynamic therapy's non-invasive profile and selective cytotoxicity complement ferroptosis' unique mode of action, which exploits iron-dependent lipid peroxidation, offering a pathway to overcome chemoresistance with lower systemic impact. The synergism between photodynamic therapy and ferroptosis is underscored by the depletion of glutathione and glutathione peroxidase four inhibitions by photodynamic therapy-induced reactive oxygen species, amplifying lipid peroxidation and enhancing ferroptotic cell death. This synergy presents an opportunity to refine cancer treatment by modulating redox homeostasis. Porphyrin-based nanoscale metal-organic frameworks have unique hybrid structures and exceptional properties. These frameworks can serve as a platform for integrating photodynamic therapy and ferroptosis through carefully designed structures and functions. These nanostructures can be engineered to deliver multiple therapeutic modalities simultaneously, marking a pivotal advance in multimodal cancer therapy. This review synthesizes recent progress in porphyrin-modified nanoscale metal-organic frameworks for combined photodynamic therapy and ferroptosis, delineating the mechanisms that underlie their synergistic effects in a multimodal context. It underscores the potential of porphyrin-based nanoscale metal-organic frameworks as advanced nanocarriers in oncology, propelling the field toward more efficacious and tailored cancer treatments.

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.

Progress and Challenges in Tumor Ferroptosis Treatment Strategies: A Comprehensive Review of Metal Complexes and Nanomedicine

Ferroptosis is a new form of regulated cell death featuring iron-dependent lipid peroxides accumulation to kill tumor cells. A growing body of evidence has shown the potential of ferroptosis-based cancer therapy in eradicating refractory malignancies that are resistant to apoptosis-based conventional therapies. In recent years, studies have reported a number of ferroptosis inducers that can increase the vulnerability of tumor cells to ferroptosis by regulating ferroptosis-related signaling pathways. Encouraged by the rapid development of ferroptosis-driven cancer therapies, interdisciplinary fields that combine ferroptosis, pharmaceutical chemistry, and nanotechnology are focused. First, the prerequisites and metabolic pathways for ferroptosis are briefly introduced. Then, in detail emerging ferroptosis inducers designed to boost ferroptosis-induced tumor therapy, including metal complexes, metal-based nanoparticles, and metal-free nanoparticles are summarized. Subsequently, the application of synergistic strategies that combine ferroptosis with apoptosis and other regulated cell death for cancer therapy, with emphasis on the use of both cuproptosis and ferroptosis to induce redox dysregulation in tumor and intracellular bimetallic copper/iron metabolism disorders during tumor treatment is discussed. Finally, challenges associated with clinical translation and potential future directions for potentiating cancer ferroptosis therapies are highlighted.

Light-Triggered Nanozymes Remodel the Tumor Hypoxic and Immunosuppressive Microenvironment for Ferroptosis-Enhanced Antitumor Immunity

Cancer immunotherapy holds significant promise for addressing diverse malignancies. Nevertheless, its efficacy remains constrained by the intricate tumor immunosuppressive microenvironment. Herein, a light-triggered nanozyme Fe-TCPP-R848-PEG (Fe-MOF-RP) was designed for remodeling the immunosuppressive microenvironment. The Fe-TCPP-MOFs were utilized not only as a core catalysis component against tumor destruction but also as a biocompatible delivery vector of an immunologic agonist, improving its long circulation and tumor enrichment. Concurrently, it catalyzes the decomposition of H2O2 within the tumor, yielding oxygen to augment photodynamic therapy. The induced ferroptosis, in synergy with photodynamic therapy, prompts the liberation of tumor-associated antigens from tumor cells inducing immunogenic cell death. Phototriggered on-demand release of R848 agonists stimulated the maturation of dendritic cells and reverted the tumor-promoting M2 phenotypes into adoptive M1 macrophages, which further reshaped the tumor immunosuppressive microenvironment. Notably, the nanozyme effectively restrains well-established tumors, such as B16F10 melanoma. Moreover, it demonstrates a distal tumor-inhibiting effect upon in situ light treatment. What is more, in a lung metastasis model, it elicits robust immune memory, conferring enduring protection against tumor rechallenge. Our study presents a straightforward and broadly applicable strategy for crafting nanozymes with the potential to effectively thwart cancer recurrence and metastasis.

Antifungal mechanism of cell-free supernatant produced by Trichoderma virens and its efficacy for the control of pear Valsa canker

Introduction

Pear Valsa canker, caused by Valsa pyri (V. pyri), poses a major threat to pear production. We aimed to assess the effectiveness of the cell-free supernatant (CFS) produced by Trichoderma virens (T. virens) to control the development of pear Valsa canker and reveal the inhibitory mechanism against the pathogenic fungi.

Results

Using morphological characteristics and phylogenetic analysis, the pathogen G1H was identified as V. pyri, and the biocontrol fungus WJ561 was identified as Trichoderma virens. CFS derived from WJ561 exhibited strong inhibition of mycelial growth and was capable of reducing the pathogenicity of V. pyri on pear leaves and twigs. Scanning electron microscopy (SEM) observations revealed deformations and shrinkages in the fungal hyphae treated with CFS. The CFS also destroyed the hyphal membranes leading to the leakage of cellular contents and an increase in the malondialdehyde (MDA) content. Additionally, CFS significantly inhibited the activities of catalase (CAT) and superoxide dismutase (SOD), and downregulated the expression of antioxidant defense-related genes in V. pyri, causing the accumulation of reactive oxygen species (ROS). Artesunate, identified as the main component in CFS by liquid chromatograph-mass spectrometry (LC-MS), exhibited antifungal activity against V. pyri.

Conclusion

Our findings demonstrate the promising potential of T. virens and its CFS in controlling pear Valsa canker. The primary inhibitory mechanism of CFS involves multiple processes, including membrane damage and negatively affecting enzymatic detoxification pathways, consequently leading to hyphal oxidative damage of V. pyri. This study lays a theoretical foundation for the utilization of T. virens to control V. pyri in practical production.

The state-of-art polyurethane nanoparticles for drug delivery applications

Nowadays, polyurethanes (PUs) stand out as a promising option for drug delivery owing to their versatile properties. PUs have garnered significant attention in the biomedical sector and are extensively employed in diverse forms, including bulk devices, coatings, particles, and micelles. PUs are crucial in delivering various therapeutic agents such as antibiotics, anti-cancer medications, dermal treatments, and intravaginal rings. Effective drug release management is essential to ensure the intended therapeutic impact of PUs. Commercially available PU-based drug delivery products exemplify the adaptability of PUs in drug delivery, enabling researchers to tailor the polymer properties for specific drug release patterns. This review primarily focuses on the preparation of PU nanoparticles and their physiochemical properties for drug delivery applications, emphasizing how the formation of PUs affects the efficiency of drug delivery systems. Additionally, cutting-edge applications in drug delivery using PU nanoparticle systems, micelles, targeted, activatable, and fluorescence imaging-guided drug delivery applications are explored. Finally, the role of artificial intelligence and machine learning in drug design and delivery is discussed. The review concludes by addressing the challenges and providing perspectives on the future of PUs in drug delivery, aiming to inspire the design of more innovative solutions in this field.