Myeloid-derived suppressor cells (MDSCs) promote immunosuppressive activities in the tumor microenvironment (TME), resulting in increased tumor burden and diminishing the anti-tumor response of immunotherapies. While primary and metastatic tumors are typically the focal points of therapeutic development, the immune cells of the TME are differentially programmed by the tissue of the metastatic site. In particular, MDSCs are programmed uniquely within different organs in the context of tumor progression. Given that MDSC plasticity is shaped by the surrounding environment, the proteomes of MDSCs from different metastatic sites are hypothesized to be unique. Comparative proteomic analysis demonstrates that liver and lung tumor-derived MDSCs have distinct proteomes that may be subject to pharmacologic manipulation.
YU J, GREEN MD, LI S, ET AL. LIVER METASTASIS RESTRAINS IMMUNOTHERAPY EFFICACY VIA MACROPHAGE-MEDIATED T CELL ELIMINATION. NAT MED. 2021;27(1):152-164. DOI:10.1038/S41591-020-1131-X