SOX2 and central nervous system cancer: Gliomas are characterized by the presence of glioma stem cells (GSCs), an extremely small tumorigenic cell population showing a high ability to self-renew, ability to generate non-tumorigenic cells and to reveal the potential multilineage differentiation, expression of high levels of undifferentiated stem cell markers like nestin, SOX-2 and β-tubulin III [8–11].