CAFs display many pro-tumor properties by secreted cytokines, chemokines, growth factors, exosomes, ECM proteins and ECM-degrading enzymes (e.g., IL-6, TNF-α, CXCL12, TGF-β, VEGF, IGF, collagen, matrix metalloproteinases) or, less frequently, show anti-tumor functions depending on their activation status [4,5,8]. The gene discussed is CXCL12; the disease is neoplasm.