CXCR2 and neoplasm: We confirmed that the signaling machinery of the ectopic CXCR2 receptor was functional as it could induce calcium mobilization, one of the first steps in G-protein coupled receptor signaling, in CXCR2-transduced NK cells upon stimulation with recombinant CXCL8 as well as with RCC tumor-derived supernatants containing CXCR2 ligands.