EDN1 and glioblastoma: We observed an upregulation of endothelial cell-specific genes in Prom1+ endothelium, including lipocalin 2, selectin, endothelin 1 and 3, nestin, VEGF C, and nitric oxide synthetase 3, suggesting that Prom1+ endothelium is the producer of a set of active angiocrine factors contributing to the growth of proneural GBM subtype.