IL6 and cancer: Cancer cells release growth factors, such as FGF-2, VEGF, PDGF, EGF, TGFβ, and cytokines and chemokines, the core group consisting of CCL2, CCL5, IL-6, IL-8, as well as other soluble factors that activate fibroblasts [182,183,184] and modulate CAF gene expression patterns [185,186] and their metabolism [187,188].