Highly potent chemotherapy provides rapid therapeutic efficacy in melanoma, but is often limited by drug resistance, off-target toxicity, and systemic toxicity. Combination therapy with chemotherapy and immunotherapy ...Highly potent chemotherapy provides rapid therapeutic efficacy in melanoma, but is often limited by drug resistance, off-target toxicity, and systemic toxicity. Combination therapy with chemotherapy and immunotherapy has attracted much attention but still faces challenges such as inconsistent immune responses and systemic toxicity. To address these limitations, we developed cathepsin B-activatable doxorubicin(DOX) prodrug nanoparticles(Cat B-NPs) for inducing tumor-specific immunogenic cell death(ICD), while minimizing off-target toxicity in normal tissues with low cathepsin B expression. The cathepsin Bactivatable DOX prodrug was synthesized by conjugating the cathepsin B-cleavable peptide(FRRL) to DOX, yielding FRRL-DOX. The amphiphilic FRRL-DOX formed stable nanoparticles(163.6 ± 13.5 nm) through intermolecular hydrophobic interaction and π-π stacking. In melanoma cells overexpressing cathepsin B, Cat B-NPs effectively induced cancer cellspecific ICD, while sparing normal cells and immune cells. When Cat B-NPs-treated B16F10cells were co-cultured with immune cells, Cat B-NPs enhanced the phagocytic activity of macrophages and induced the maturation of dendritic cells(DCs). In melanoma models,Cat B-NPs passively accumulated at tumor tissues through the enhanced permeability and retention effect and were selectively activated by intratumoral cathepsin B, enabling highdose treatment that induced robust ICD. Importantly, combination therapy with Cat B-NPs and anti-PD-L1 antibody enhanced ICD, DC maturation and T-cell activation, resulting in complete tumor regression in 50% of treated mice by converting the immunosuppressive tumor environment into an immune-responsive state. In a lung metastasis model, highdose Cat B-NPs with anti-PD-L1 also suppressed metastatic burden without systemic toxicity, supporting their potential as a safe and effective chemo-immunotherapy for melanoma.展开更多
Synergistic immunotherapy of immune checkpoint blockade (ICB) and immunogenic cell death (ICD) has shown remarkable therapeutic efficacy in various cancers. However, patients show low response rates and undesirable ou...Synergistic immunotherapy of immune checkpoint blockade (ICB) and immunogenic cell death (ICD) has shown remarkable therapeutic efficacy in various cancers. However, patients show low response rates and undesirable outcomes to these combination therapies owing to the recycling mechanism of programmed death-ligand 1 (PD-L1) and the systemic toxicity of ICD-inducing chemotherapeutic drugs. Herein, we propose all-in-one glycol chitosan nanoparticles (CNPs) that can deliver anti-PD-L1 peptide (PP) and doxorubicin (DOX) to targeted tumor tissues for a safe and more effective synergistic immunotherapy. The PP-CNPs, which are prepared by conjugating ᴅ-form PP (NYSKPTDRQYHF) to CNPs, form stable nanoparticles that promote multivalent binding with PD-L1 proteins on the targeted tumor cell surface, resulting in effective lysosomal PD-L1 degradation in contrast with anti-PD-L1 antibody, which induces recycling of endocytosed PD-L1. Consequently, PP-CNPs prevent subcellular PD-L1 recycling and eventually destruct immune escape mechanism in CT26 colon tumor-bearing mice. Moreover, the ICD inducer, DOX is loaded into PP-CNPs (DOX-PP-CNPs) for synergistic ICD and ICB therapy, inducing a large number of damage-associated molecular patterns (DAMPs) in targeted tumor tissues with minimal toxicity in normal tissues. When the DOX-PP-CNPs are intravenously injected into CT26 colon tumor-bearing mice, PP and DOX are efficiently delivered to the tumor tissues via nanoparticle-derived passive and active targeting, which eventually induce both lysosomal PD-L1 degradation and substantial ICD, resulting in a high rate of complete tumor regression (CR: 60%) by a strong antitumor immune response. Collectively, this study demonstrates the superior efficacy of synergistic immunotherapy using all-in-one nanoparticles to deliver PP and DOX to targeted tumor tissues.展开更多
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT)(RS-2024-00351185, RS-2025-02219039)by the Korea Health Industry Development Institute (KHIDI)grant funded by the Korea government (MOHW)(RS-2023-KH135133)by Korea Drug Development Fund (KDDF)funded by Ministry of Science and ICT,Ministry of Trade,Industry,and Energy,and Ministry of Health and Welfare(RS-2025-02223093)。
文摘Highly potent chemotherapy provides rapid therapeutic efficacy in melanoma, but is often limited by drug resistance, off-target toxicity, and systemic toxicity. Combination therapy with chemotherapy and immunotherapy has attracted much attention but still faces challenges such as inconsistent immune responses and systemic toxicity. To address these limitations, we developed cathepsin B-activatable doxorubicin(DOX) prodrug nanoparticles(Cat B-NPs) for inducing tumor-specific immunogenic cell death(ICD), while minimizing off-target toxicity in normal tissues with low cathepsin B expression. The cathepsin Bactivatable DOX prodrug was synthesized by conjugating the cathepsin B-cleavable peptide(FRRL) to DOX, yielding FRRL-DOX. The amphiphilic FRRL-DOX formed stable nanoparticles(163.6 ± 13.5 nm) through intermolecular hydrophobic interaction and π-π stacking. In melanoma cells overexpressing cathepsin B, Cat B-NPs effectively induced cancer cellspecific ICD, while sparing normal cells and immune cells. When Cat B-NPs-treated B16F10cells were co-cultured with immune cells, Cat B-NPs enhanced the phagocytic activity of macrophages and induced the maturation of dendritic cells(DCs). In melanoma models,Cat B-NPs passively accumulated at tumor tissues through the enhanced permeability and retention effect and were selectively activated by intratumoral cathepsin B, enabling highdose treatment that induced robust ICD. Importantly, combination therapy with Cat B-NPs and anti-PD-L1 antibody enhanced ICD, DC maturation and T-cell activation, resulting in complete tumor regression in 50% of treated mice by converting the immunosuppressive tumor environment into an immune-responsive state. In a lung metastasis model, highdose Cat B-NPs with anti-PD-L1 also suppressed metastatic burden without systemic toxicity, supporting their potential as a safe and effective chemo-immunotherapy for melanoma.
基金supported by grants from the National Research Foundation(NRF)of Koreafunded by the Ministry of Science(NRF-2022M3H4A1A03067401 and NRF-2021R1C1C2005460)and the Intramural Research Program of KIST.
文摘Synergistic immunotherapy of immune checkpoint blockade (ICB) and immunogenic cell death (ICD) has shown remarkable therapeutic efficacy in various cancers. However, patients show low response rates and undesirable outcomes to these combination therapies owing to the recycling mechanism of programmed death-ligand 1 (PD-L1) and the systemic toxicity of ICD-inducing chemotherapeutic drugs. Herein, we propose all-in-one glycol chitosan nanoparticles (CNPs) that can deliver anti-PD-L1 peptide (PP) and doxorubicin (DOX) to targeted tumor tissues for a safe and more effective synergistic immunotherapy. The PP-CNPs, which are prepared by conjugating ᴅ-form PP (NYSKPTDRQYHF) to CNPs, form stable nanoparticles that promote multivalent binding with PD-L1 proteins on the targeted tumor cell surface, resulting in effective lysosomal PD-L1 degradation in contrast with anti-PD-L1 antibody, which induces recycling of endocytosed PD-L1. Consequently, PP-CNPs prevent subcellular PD-L1 recycling and eventually destruct immune escape mechanism in CT26 colon tumor-bearing mice. Moreover, the ICD inducer, DOX is loaded into PP-CNPs (DOX-PP-CNPs) for synergistic ICD and ICB therapy, inducing a large number of damage-associated molecular patterns (DAMPs) in targeted tumor tissues with minimal toxicity in normal tissues. When the DOX-PP-CNPs are intravenously injected into CT26 colon tumor-bearing mice, PP and DOX are efficiently delivered to the tumor tissues via nanoparticle-derived passive and active targeting, which eventually induce both lysosomal PD-L1 degradation and substantial ICD, resulting in a high rate of complete tumor regression (CR: 60%) by a strong antitumor immune response. Collectively, this study demonstrates the superior efficacy of synergistic immunotherapy using all-in-one nanoparticles to deliver PP and DOX to targeted tumor tissues.
