Tumor phagocytosis-driven STING activation invigorates antitumor immunity and reprograms the tumor micro-environment

• Published in: Journal of controlled release 2024-09, Vol.373, p.55-69
• Main Authors: Lee, Susam, Hong, Kyeong Hee, Park, Heewon, Ha, JongHoon, Lee, Seung Eon, Park, Dong Jin, Jeong, Seong Dong, Kim, Seohyeon, Kim, Dahae, Ahn, JiWon, Lee, Han-Woong, Koh, Won-Gun, Ha, Sang-Jun, Kim, Yeu-Chun
• Format: Article
• Language: English
• Subjects: Animals; Antibiotics, Antineoplastic - administration & dosage; Antigen-Presenting Cells - drug effects; Antigen-Presenting Cells - immunology; Cell Line, Tumor; Doxorubicin - administration & dosage; Drug delivery system; Female; Humans; Immunogenic cell death; Immunogenic Cell Death - drug effects; Membrane Proteins - immunology; Mice; Mice, Inbred C57BL; Nanoparticles - administration & dosage; Nanoparticles - chemistry; Neoplasms - drug therapy; Neoplasms - immunology; Neoplasms - therapy; Peptides - administration & dosage; Peptides - chemistry; Phagocytosis - drug effects; Stimulator of interferon genes; Tumor micro-environment; Tumor Microenvironment - drug effects; Tumor Microenvironment - immunology; Tumor phagocytosis-driven STING activation
• ISSN: 0168-3659; 1873-4995; 1873-4995
• DOI: 10.1016/j.jconrel.2024.07.004

Immunogenic cell death (ICD) holds the potential for in situ tumor vaccination while concurrently eradicating tumors and stimulating adaptive immunity. Most ICD inducers, however, elicit insufficient immune responses due to negative feedback against ICD biomarkers, limited infiltration of antitumoral immune cells, and the immunosuppressive tumor micro-environment (TME). Recent findings highlight the pivotal roles of stimulators of interferon gene (STING) activation, particularly in stimulating antigen-presenting cells (APCs) and TME reprogramming, addressing ICD limitations. Herein, we introduced ‘tumor phagocytosis-driven STING activation’, which involves the activation of STING in APCs during the recognition of ICD-induced cancer cells. We developed a polypeptide-based nanocarrier encapsulating both doxorubicin (DOX) and diABZI STING agonist 3 (dSA3) to facilitate this hypothesis in vitro and in vivo. After systemic administration, nanoparticles predominantly accumulated in tumor tissue and significantly enhanced anticancer efficacy by activating tumor phagocytosis-driven STING activation in MC38 and TC1 tumor models. Immunological activation of APCs occurred within 12 h, subsequently leading to the activation of T cells within 7 days, observed in both the TME and spleen. Furthermore, surface modification of nanoparticles with cyclic RGD (cRGD) moieties, which actively target integrin αvβ3, enhances tumor accumulation and eradication, thereby verifying the establishment of systemic immune memory. Collectively, this study proposes the concept of tumor phagocytosis-driven STING activation and its effectiveness in generating short-term and long-term immune responses. [Display omitted]