Immunocytochemistry showed that Sox2 and Bmi1, which are necessary for the normal functioning of both embryonic stem cells and neural stem cells [39], [40], were expressed by a majority of cells in the low- and high-grade gliomas cultures studied (10/10 and 6/6 cultures, respectively, Figure 3A, C, and D). This evidence concerns the gene SOX2 and central nervous system cancer.