Gliomas and medulloblastomas are the most common types of brain tumors; several studies reported that the aberration of Notch components in brain tumors, for example, the overexpression of Notch1, 3 and 4, ASCL1, and Hey1, are highly correlated with a higher grade of glioma and poor prognosis. This evidence concerns the gene ASCL1 and glioma.