CXCR1 and neoplasm: Other than the common immune suppressive mechanisms mentioned above, NETs shield immune effector cells from target tumor cells in the TME, which is a similar function to “nets.” Cancer cells and endothelial cells are the primary cells that generate ELR+ CXCL1 and CXCL2 as agonists of CXCR1 and CXCR2, respectively, attracting neutrophils that can correspondingly extrude NETs.