CXCL8 and neoplasm: The high level of IL-8 activates β2 integrins (CD18) to arrest neutrophils during transmigration (DiVietro et al., 2001), attracts immunosuppressive CXCR2+ N2-phenotype tumor-associated neutrophils (Alfaro et al., 2016), and stimulates the formation of neutrophil extracellular traps.