STING ligand c-di-GMP improves cancer vaccination against metastatic breast cancer.

ABSTRACT: Cancer vaccination may be our best and most benign option for preventing or treating metastatic cancer. However, breakthroughs are hampered by immune suppression in the tumor microenvironment. In this study, we analyzed whether cyclic diguanylate (c-di-GMP), a ligand for stimulator of interferon genes (STING), could overcome immune suppression and improve vaccination against metastatic breast cancer. Mice with metastatic breast cancer (4T1 model) were therapeutically immunized with an attenuated Listeria monocytogenes (LM)-based vaccine, expressing tumor-associated antigen Mage-b (LM-Mb), followed by multiple low doses of c-di-GMP (0.2 μmol/L). This treatment resulted in a striking and near elimination of all metastases. Experiments revealed that c-di-GMP targets myeloid-derived suppressor

SUBMITTER: Chandra D 

PROVIDER: S-EPMC4264585 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature