Accordingly, key elements in the tumor stroma are CAFs: metabolically active spindle-shaped cells with enhanced proliferative and migratory properties that release many growth factors and proinflammatory cytokines, such as transforming growth factor-β (TGF-β), vascular endothelial growth factor (VEGF), and interleukin-6 (IL-6). This evidence concerns the gene IL6 and neoplasm.