Heating tumors with tumor cell-derived nanoparticles to enhance chemoimmunotherapy for colorectal cancer.

Aim: To investigate the mechanism of doxorubicin (DOX)-induced immunogenic cell death (ICD) and to improve immunotherapy efficacy. Materials & methods: In this study, hybrid vesicles containing DOX (HV-DOX) were prepared by thin-film hydration with extrusion, and the formulated nanoparticles were characterized physically. Furthermore, in vitro experiments and animal models were used to investigate the efficacy and new mechanisms of chemotherapy combined with immunotherapy. Results: DOX improved tumor immunogenicity by alkalinizing lysosomes, inhibiting tumor cell autophagy and inducing ICD. HVs could activate dendritic cell maturation, synergistically enhancing chemotherapeutic immunity. Conclusion: The mechanism of DOX-induced ICD was explored, and antitumor immunity was synergistically activated by HV-DOX to improve chemotherapeutic drug loading and provide relevant antigenic information.

Treatment with Mesenchymal Stem Cell-Derived Nanovesicle-Containing Gelatin Methacryloyl Hydrogels Alleviates Osteoarthritis by Modulating Chondrogenesis and Macrophage Polarization.

Osteoarthritis is a degenerative disorder that can severely affect joints, and new treatment strategies are urgently needed. Administration of mesenchymal stem cell (MSC)-derived exosomes is a promising therapeutic strategy in osteoarthritis treatment. However, the poor yield of exosomes is an obstacle to the use of this modality in the clinic. Herein, a promising strategy is developed to fabricate high-yield exosome-mimicking MSC-derived nanovesicles (MSC-NVs) with enhanced regenerative and anti-inflammatory capabilities. MSC-NVs are prepared using an extrusion approach and are found to increase chondrocyte and human bone marrow MSC differentiation, proliferation, and migration, in addition to inducing M2 macrophage polarization. Furthermore, gelatin methacryloyl (GelMA) hydrogels loaded with MSC-NVs (GelMA-NVs) are formulated, which exhibit sustained release of MSC-NVs and are shown to be biocompatible with excellent mechanical properties. In a mouse osteoarthritis model constructed by surgical destabilization of the medial meniscus (DMM), GelMA-NVs effectively ameliorate osteoarthritis severity, reduce the secretion of catabolic factors, and enhance matrix synthesis. Furthermore, GelMA-NVs induce M2 macrophage polarization and inflammatory response inhibition in vivo. The findings demonstrate that GelMA-NVs hold promise for osteoarthritis treatment through modulation of chondrogenesis and macrophage polarization.

GE11 Modified PLGA/TPGS Nanoparticles Targeting Delivery of Salinomycin to Breast Cancer Cells.

Salinomycin (Sal) is a potent inhibitor with effective anti-breast cancer properties in clinical therapy. The occurrence of various side effect of Sal greatly limits its application. The epidermal growth factor receptor (EGFR) family is a family of receptors highly expressed in most breast cancer cells. GE11 is a dodecapeptide which shows excellent EGFR affinity. A series of nanoparticles derivatives with GE11 peptide conjugated PLGA/TPGS were synthesized. Nanoprecipitation method was used to prepare the Sal loaded nanoparticles at the optimized concentration. The characterization, targeting efficacy, and antitumor activity were detected both in vitro and in vivo. Encapsulation of Sal in GE11 modified PLGA/TPGS nanoparticles shows an improved therapy efficacy and lower systemic side effect. This represents the delivery system a promising strategy to enhance the therapeutic effect against EGFR highly expressed breast cancer.

Immunotherapy of Tumor RNA-Loaded Lipid Nanoparticles Against Hepatocellular Carcinoma.

PURPOSE: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Most current therapeutic strategies primarily include localized treatment, lacking effective systemic strategies. Meanwhile, recent studies have suggested that RNA vaccines can effectively activate antigen-presenting cells (APCs) and lymphocytes to produce a strong systemic immune response and inhibit tumor growth. However, tumor vaccines loaded with a single tumor antigen may induce immunosuppression and immune evasion, while identifying tumor-specific antigens can require expensive and laborious procedures. Therefore, the use of whole tumor cell antigens are currently considered to be promising, potentially effective, methods. Previously, we developed a targeted liposome-polycation-DNA (LPD) complex nanoparticle that possess a small size, high RNA encapsulation efficiency, and superior serum stability. These particles were found to successfully deliver RNA to tumor sites. In the current study, we encapsulated total tumor-derived RNA in lipid nanoparticles (LNPs) to target dendritic cells (DCs) to incite expeditious and robust anti-tumor immunity. METHODS: Total tumor-derived RNA was extracted from liver cancer cells (Hepa1-6 cells). LNPs loaded with tumor RNA were then prepared thin-film hydration method. The ability of RNA LNPs to induce DC maturation, cytotoxicity, and anti-tumor activity, was investigated in vitro and in vivo. RESULTS: The average particle size of LNPs and RNA LNPs was 102.22 ± 4.05 nm and 209.68 ± 6.14 nm, respectively, while the zeta potential was 29.97 ± 0.61 mV and 42.03 ± 0.42 mV, respectively. Both LNPs and RNA LNP vaccines exhibited good distribution and stability. In vitro, RNA LNP vaccines were capable of promoting DC maturation and inducing T lymphocytes to kill Hepa1-6 cells. In vivo, RNA LNP vaccines effectively prevent and inhibit HCC growth. CONCLUSION: RNA LNPs may serve as an effective antigen specific vaccine to induce anti-tumor immunity for HCC.