CSF2 and pancreatic neoplasm: Meanwhile, in a murine model of pancreatic cancer, activating mutations in KRAS (KRASG12D) induced MDSCs via the production of granulocyte macrophage colony-stimulating factor (GM-CSF) and inhibition of CD8+ T-cell infiltration into tumor tissues, which contributed to the establishment of an immunosuppressive tumor microenvironment [49].