TGFB1 and glioblastoma: Transforming growth factor beta 2 (TGFβ) is being explored as a therapeutic target for the treatment of HGGs, including GBM [14,15,16,17,18,19,20,21,22], in part owing to the compelling evidence that the amplified activity of the TGFβ-SMAD signaling pathway contributes to the malignant phenotype and poor prognosis of GBM in adult patients by enhancing tumor growth, invasion, and angiogenesis, as well as compromised immune surveillance [14,15,16,17,18,19,20,21,22].