NOTCH1 and glioblastoma: NOTCH1 is a part of the NOTCH signaling network, an intercellular signaling pathway conserved to regulate interactions between neighboring cells.17 During development, activation of NOTCH1 before birth leads to the differentiation of radial glia, while after birth, it leads to the differentiation of astrocytes.18 Additionally, NOTCH1 is found to be more highly expressed in glioblastoma stem cells (GSCs) located in the tumor periphery as opposed to those in the tumor core.19,20