IL6 and neoplasm: CAF with tumor-promoting functions secrete growth factors (HGF, IGF1, CTGF, PDGF, VEGF, LIF), cytokines (IL-1, IL-4, IL-6, IL-8, IL-10, TGF-β), and chemokines (CCL2, CCL5, CXCL5, CXCL9, CXCL10, CXCL12), WNT5α, and bone morphogenic protein 4 (BMP4), which promote tumor progression [144].