Soluble molecules: Secreted by various cellular players of the GBM microenvironment, the TME contains various growth factors and cytokines, such as (i) tumor-promoting cytokines, including interleukin (IL)-1, and basic fibroblast growth factor (bFGF) and (ii) immunosuppressive chemical mediators, including TGF-β, IL-10, IL-6 and prostaglandin E-2 (PGE2) [95,96]. This evidence concerns the gene TGFB1 and neoplasm.