SLC2A1 and astrocytoma (excluding glioblastoma): As expected, in low-grade glioma (WHO grade II astrocytoma and oligodendroglioma), where Gd-enhanced MR indicates no BBB disruption, the ZO-1 immunofluorescence showed a continuous signal lining the Glut-1 positive vessels (Supplementary Figure S6 and Supplementary Table S3).