Tumor-derived nanovesicles enhance cancer synergistic chemo-immunotherapy by promoting cGAS/STING pathway activation and immunogenetic cell death

Life Sci. 2024 Jul 1:348:122687. doi: 10.1016/j.lfs.2024.122687. Epub 2024 May 7.

Abstract

Aims: Checkpoint blockade immunotherapy is a promising therapeutic modality that has revolutionized cancer treatment; however, the therapy is only effective on a fraction of patients due to the tumor environment. In tumor immunotherapy, the cGAS-STING pathway is a crucial intracellular immune response pathway. Therefore, this study aimed to develop an immunotherapy strategy based on the cGAS-STING pathway.

Materials and methods: The physicochemical properties of the nanoparticles EM@REV@DOX were characterized by TEM, DLS, and WB. Subcutaneous LLC xenograft tumors were used to determine the biodistribution, antitumor efficacy, and immune response. Blood samples and tissues of interest were harvested for hematological analysis and H&E staining.

Significance: Overall, our designed nanovesicles provide a new perspective on tumor immunotherapy by ICD and cGAS-STING pathway, promoting DCs maturation, macrophage polarization, and activating T cells, offering a meaningful strategy for accelerating the clinical development of immunotherapy.

Key findings: EM@REV@DOX accumulated in the tumor site through EPR and homing targeting effect to release REV and DOX, resulting in DNA damage and finally activating the cGAS-STING pathway, thereby promoting DCs maturation, macrophage polarization, and activating T cells. Additionally, EM@REV@DOX increased the production of pro-inflammatory cytokines (e.g., TNF-α and IFN-β). As a result, EM@REV@DOX was effective in treating tumor-bearing mice and prolonged their lifespans. When combined with αPD-L1, EM@REV@DOX significantly inhibited distant tumor growth, extended the survival of mice, and prevented long-term postoperative tumor metastasis, exhibiting great potential in antitumor immunotherapy.

Keywords: Exosome; Immunogenic cell death; Immunotherapy; Lung Cancer; cGAS-STING pathway.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Doxorubicin / administration & dosage
  • Doxorubicin / pharmacology
  • Female
  • Humans
  • Immunogenic Cell Death / drug effects
  • Immunotherapy* / methods
  • Membrane Proteins* / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Nanoparticles* / chemistry
  • Neoplasms / drug therapy
  • Neoplasms / immunology
  • Neoplasms / pathology
  • Neoplasms / therapy
  • Nucleotidyltransferases* / metabolism
  • Signal Transduction
  • Xenograft Model Antitumor Assays

Substances

  • cGAS protein, mouse
  • Sting1 protein, mouse
  • STING1 protein, human