NOTCH1 and glioblastoma: Furthermore, using real-time PCR (qPCR) and Western blot analysis, the expressions of proteins that play role in the activation of astrocytes, such GFAP and vimentin, as well as GBM malignancy, such as Notch-1 and survivin, were investigated in the drug-treated LN229–astrocyte co-culture and compared with the mono-cultures.