TNF Receptor-2 Facilitates an Immunosuppressive Microenvironment in the Liver to Promote the Colonization and Growth of Hepatic Metastases

Abstract

Successful colonization by a cancer cell of a distant metastatic site requires immune escape in the new microenvironment. TNF signaling has been implicated broadly in the suppression of immune surveillance that prevents colonization at the metastatic site and therefore must be blocked. In this study, we explored how TNF signaling influences the efficiency of liver metastasis by colon and lung carcinoma in mice that are genetically deficient for the TNF receptor TNFR2. We found a marked reduction in liver metastases that correlated with a greatly reduced accumulation at metastatic sites of CD11b(+)GR-1(+) myeloid cells with enhanced arginase activity, identified as myeloid-derived suppressor ..