CAFs produce cytokines and growth factors that promote tumor proliferation in lung cancer cells in autocrine and paracrine manners,206, 207, 208, 209 such as C‐X‐C motif chemokine ligands including CXCL8, CXCL2,210 CXCL12172; TGF‐β,174 and PDGF (Figure 3A).211, 212. This evidence concerns the gene CXCL8 and lung cancer.