For tumor angiogenesis, tumor growth depends on the formation of new blood vessels, and CAFs can promote tumor angiogenesis through secretion or high expression of various pro-angiogenic and other factors, including vascular endothelial growth factor (VEGF) (71–73), interleukin-6 (IL-6) (72), fibroblast growth factor (FGF) (71), CCL2 (74), galectin-1 (75), milk fat globule-EGF factor 8 (MFGE8) (76), Wingless-type MMTV integration site family member 2 (WNT2) (77) and FOS-like 2 (FOSL2) (78). The gene discussed is CCL2; the disease is neoplasm.