These observations prompted the functional evaluation of SOX2 roles within these cells, and these studies led to the demonstration of an essential role for SOX2 in the maintenance of cancer stem cells within gliomas and glioblastomas (the most severe and deadly neural tumors), as well as in CSC/TIC in several more common tumor types; this functional relevance was proven in both patient-derived cells and mouse models. The gene discussed is SOX2; the disease is nervous system cancer.