This is because CD133 remains the most commonly used human glioma stem cell marker and has been successfully applied for the identification and isolation of glioma CSCs, despite ongoing controversies about the existence of CD133− glioma stem cells [3,4,45,52-54,56-58] and it role in predicting glioma prognosis and survival [62-64]. This evidence concerns the gene PROM1 and central nervous system cancer.