IL6 and neoplasm: The TME not only plays a supporting role for various cells, including tumor cells, immune cells, vascular endothelial cells, and fibroblasts but also forms the ECM (including collagen, laminin, and proteoglycan complexes) and secretes multiple cytokines, such as SDF-1 [23], IL-6 [24], bFGF [25], and EGF [26].