CXCR2 and cancer: CXCL1/CXCR2-mediating signaling cascades, such as PI3K/Akt, mitogen-activated protein kinase (MAPK), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), have been considered the regulatory signaling pathways for migration and invasion in several cancer cells (15, 35).