CXCR2 and cancer: Furthermore, other chemokine receptors, including CXCR1, CXCR2, CCR5, and CXCR4, have also been implicated with cancer metastasis to specific organs (Balkwill, 2012, Mishan et al., 2016, Zlotnik et al., 2011) and thus might compensate for each other if only one of them is targeted.