CXCR1 and neoplasm: Activation of chemokine receptors (CXCR1 and CXCR2) has pro-angiogenic and pro-inflammatory effects, inducing several signaling pathways, such as the protein kinase C, phospholipase C, PI3K/AKT/mTOR, RAS/RAF/MEK/ERK and NF-kB pathways, promoting tumor cell survival, proliferation, and dissemination [320].