NOTCH1 and malignant glioma: For further elucidating the distinct roles of Notch 1 and Notch 2 in the development and progression of astrocytic gliomas, in the present study, the effect of enforced expression of Notch2 with transfection of Notch2 plasmid in cultured malignant glioma cells and xenograft gliomas in nude mice was studied as compared to that of knocking down Notch1.