NADPH Oxidases-Inspired Reactive Oxygen Biocatalysts with Electron-Rich Pt Sites to Potently Amplify Immune Checkpoint Blockade Therapy

Spatial Configuration-Guided Design of Covalent Organic Framework-Based Artificial Metalloantioxidases for Inhibiting Inflammatory Cascades and Regulating Bone Homeostasis

Intense oxidative stress in bone tissues can trigger the hyperactivation of neutrophils, thereby causing inflammatory cascades to deteriorate bone homeostasis. Here, inspired by the catalytic centers of natural antioxidases, we introduce the spatial configuration-guided design of covalent organic framework (COF)-based artificial metalloantioxidases for inhibiting inflammatory cascades and regulating bone homeostasis. Specifically, the hexaiminohexaazatrinaphthalene COF with ruthenium coordination (S-HACOF-Ru), featuring electron-rich centers with a spatial configuration, demonstrates exceptional antioxidase-like reactive oxygen species (ROS) scavenging capabilities for efficiently mitigating the oxidative stress. As a result, S-HACOF-Ru efficiently prevents the generation of neutrophil extracellular traps and inhibits the release of myeloperoxidase (MPO). By preventing MPO-induced activation of nuclear factor-kappa B and inhibiting proinflammatory macrophage polarization, S-HACOF-Ru successfully blocks the neutrophil-macrophage inflammatory cascades. This intervention promotes bone homeostasis by a shift from bone resorption to tissue regeneration, which can efficiently inhibit alveolar bone loss in periodontal tissues and reverse cartilage damage in ankle joint cavities. We propose that this design strategy provides an intriguing avenue for developing new artificial antioxidases and biocatalytic materials with potential applications in treating a wide range of chronic inflammatory diseases.

Multifunctional biomimetic liposomal nucleic acid scavengers inhibit the growth and metastasis of breast cancer

Chemotherapy and surgery, though effective in cancer treatment, trigger the release of nucleic acid-containing pro-inflammatory compounds from damaged tumor cells, known as nucleic acid-associated damage-associated molecular patterns (NA-DAMPs). This inflammation promotes tumor metastasis, and currently, no effective treatment exists for this treatment-induced inflammation and subsequent tumor metastasis. To address this challenge, we developed a biomimetic liposome complex (Lipo-Rh2) incorporating a hybrid structure of liposomes and dendritic polymers, mimicking cell membrane morphology. Lipo-Rh2 leverages the multivalent surface properties of dendritic polymers to clear cell-free nucleic acids while serving as both a structural stabilizer and targeting ligand via embedded ginsenoside Rh2. Experimental data show that Lipo-Rh2 effectively reduces free nucleic acids in mouse serum through charge interactions, downregulates Toll-like receptor expression, decreases inflammatory cytokine secretion, and inhibits both primary tumor growth and metastasis. Compared to the current nucleic acid scavenger PAMAM-G3, Lipo-Rh2 demonstrates stronger antitumor effects, lower toxicity, and enhanced targeting capabilities. This biomimetic liposome-based nucleic acid scavenger represents a novel approach to nucleic acid clearance, expanding the framework for designing effective therapeutic agents.

Applying Ultrasound to Mechanically and Noninvasively Sensitize Prostate Tumors to TRAIL-Mediated Apoptosis

Non-surgical and safe prostate cancer (PCa) therapies are in demand. Soluble tumor necrosis factor (TNF-α) related apoptosis inducing ligand (TRAIL), a cancer-specific drug, shows preclinical efficacy but has a short circulation half-life. This research has shown that physiological fluid shear stress activates mechanosensitive ion channels (MSCs), such as Piezo1, enhancing TRAIL-mediated apoptosis in cancer cells. Herein, noninvasive, focal ultrasound (FUS) is implemented to augment the pro-apoptotic effects of TRAIL. Using thermally safe FUS parameters, it is observed that TRAIL sensitivity increases with higher FUS pressure in PCa cells, mediated by Piezo1. This is confirmed by examining the effects of calcium chelation, MSC inhibitors, and PIEZO knockdown. In vivo, a multi-dose study with 10 min FUS exposure shows that 0 and 4-h intervals between TRAIL and FUS significantly reduce tumor burden, with an increase in apoptosis evident by enhanced cleaved-caspase 3 expression. This mechanotherapy offers a clinically translatable approach by utilizing widely available FUS technology, applicable to treat additional cancer types.

Targeting novel regulated cell death: disulfidptosis in cancer immunotherapy with immune checkpoint inhibitors

The battle against cancer has evolved over centuries, from the early stages of surgical resection to contemporary treatments including chemotherapy, radiation, targeted therapies, and immunotherapies. Despite significant advances in cancer treatment over recent decades, these therapies remain limited by various challenges. Immune checkpoint inhibitors (ICIs), a cornerstone of tumor immunotherapy, have emerged as one of the most promising advancements in cancer treatment. Although ICIs, such as CTLA-4 and PD-1/PD-L1 inhibitors, have demonstrated clinical efficacy, their therapeutic impact remains suboptimal due to patient-specific variability and tumor immune resistance. Cell death is a fundamental process for maintaining tissue homeostasis and function. Recent research highlights that the combination of induced regulatory cell death (RCD) and ICIs can substantially enhance anti-tumor responses across multiple cancer types. In cells exhibiting high levels of recombinant solute carrier family 7 member 11 (SLC7A11) protein, glucose deprivation triggers a programmed cell death (PCD) pathway characterized by disulfide bond formation and REDOX (reduction-oxidation) reactions, termed "disulfidptosis." Studies suggest that disulfidptosis plays a critical role in the therapeutic efficacy of SLC7A11high cancers. Therefore, to investigate the potential synergy between disulfidptosis and ICIs, this study will explore the mechanisms of both processes in tumor progression, with the goal of enhancing the anti-tumor immune response of ICIs by targeting the intracellular disulfidptosis pathway.