Blockade of this interleukin reduces MDSC infiltration in the lung.224 In the case of CRC, KRAS mutations repress interferon regulatory factor 2 (IRF2), resulting in decreased IRF2/CXCL3 binding and, thus, higher CXCL3/CXCR2 coupling on MDSCs, promoting their migration to the TIME.225,226 In addition, it has been shown that GM-CSF upregulation by pancreatic and colorectal tumors enhances the infiltration of MDSCs to the TME,227–231 especially the expansion of immunosuppressive Gr1+CD11b+ myeloid cells,227 adding another element to the association between oncogenic KRAS and immune evasion. The gene discussed is IRF2; the disease is colorectal carcinoma.