IL6 and neoplasm: CAFs and their secreted soluble factors including cytokines (TGF-B, IL-4, IL-6), chemokines (CCLX and CXCL family members), pro-angiogenesis factors (VEGF, PDGF, and HIF), enzymes (MMPs), and ECM proteins (ectodysplasin-A and collagen type-I) contribute to tumor progression (124, 125).