In as much as peritumor tissue-derived CSC presented greater chemoresistance to treatments respect to core tumor derived-CSC [23], we decided to investigate by RT-qPCR the expression of the main modulators of EMT and/or drug resistance such as TWIST, EDN1 and PRKCA in several samples of GBM CSC (Figure 7B). The gene discussed is EDN1; the disease is neoplasm.