Silencing the Killers: Paracrine Immune Suppression in Pancreatic Cancer

Pancreatic cancers are characterized by high levels of inflammatory cells and profound immune suppression. In this issue of Cancer Cell, Bayne et al. and Pylayeva-Gupta et al. show that KRAS-driven, tumor cell-secreted GM-CSF recruits myeloid-derived suppressor cells to the stroma to abrogate tumor cell immune clearance by killer T lymphocytes.