This kind of cells is being recruited by chemotactic molecules that are secreted by cancer, immune and stromal cells such as prostaglandin E2 (PGE2), vascular endothelial growth factor (VEGF), CXC chemokine ligand (CXCL)12, fibroblast growth factor (FGF)-2, and platelet-derived growth factor (PDGF) [38]. This evidence concerns the gene VEGFA and cancer.