NOS3 and neoplasm: The same group previously investigated the role of nitric oxide (NO) activity in the perivascular niche using a mouse genetic model of PDGF-induced gliomas [101] and found that eNOS (endothelial nitric oxide synthase) expression is elevated in the tumor vasculature adjacent to the glioma cells, and the Notch signaling driven by NO/cGMP pathway induces the SP phenotype in primary glioma cell cultures.