TERT and central nervous system cancer: In addition, while human astrocytes engineered with combinations of human TERT and H-Ras expression and inhibition of the TP53 pathway either by SV40 T/t-Ag or by HPV E6 and E7 generate gliomas with high-grade histology5,6, how well these models recapitulate the full spectrum of glioma pathobiology, especially in terms of GBM heterogeneity, has not been well defined.