CXCR1/2 are expressed by (a) cancer cells (cancer cell lines and cancer cells from tumour biopsies), which are critical for cancer progression and metastasis, (b) endothelial cells, to promote proliferation, survival and migration of vascular endothelial cells, leading to an angiogenic phenotype, (c) and inflammatory cells (neutrophils/tumour-associated macrophages), leading to an immune-tolerant microenvironment that promotes metastasis [44,45,46,47]. This evidence concerns the gene CXCR1 and cancer.