TGFB1 and neoplasm: Transforming growth factor-beta (TGF-β) signaling plays a pivotal role in immune modulation and tumor progression in GBM.319 This signaling pathway begins when TGF-β binds to type I and type II serine/threonine kinase receptors, triggering the phosphorylation and activation of receptor-regulated SMAD proteins (SMAD2 and SMAD3).