CXCL12 and neoplasm: Interestingly, CAFs promote tumor growth, angiogenesis, immunosuppression, and metastasis via the secretion of growth factors such as VEGF [173,174], TGF-β [175], cytokines and chemokines (IL-6, CXCL12) [123,176,177], PDGF, and MMPs [178,179,180].