A substantial body of research substantiates that CC chemokines (e.g., CCL2, CCL5) and CXC chemokines (e.g., CXCL1, CXCL2, CXCL5) recruit diverse immune cells, such as CCR2+ monocytes and CXCR2+ neutrophils, to tumor sites. This evidence concerns the gene CXCR2 and neoplasm.