NEUROD1 and infection: After overexpressing Neurog2 or NeuroD1 in GBM cells (U251; Sigma-Aldrich), we found that the majority of virally-infected GBM cells had a neuronal morphology, and showed immature neuronal markers such as doublecortin (DCX) and β3-tubulin (Tuj1) at 20 days post-infection (dpi), but only a small proportion of Ascl1-infected GBM cells were converted into neuron-like cells (Figure 1A).