Interestingly, we found that among the Nestin+ CD31+ or CD133+ CD31+ cells, high expression of CD31 was mostly associated with low expression of neural stem cell markers (Nestin or CD133) and vice versa (Fig. 6a, arrows), suggesting a certain loss and gain of specific marker genes during the process of endothelial lineage commitment from GBM neural stem-like cells. This evidence concerns the gene PECAM1 and glioblastoma.