PROM1 and oligoastrocytoma: The association of PATZ1 expression with CD133 expression was further confirmed by the analysis of two separate experimental datasets consisting of cell lines established from 7 GBMs, 2 oligoastrocytomas and 5 normal foetuses plus primary biopsies from 6 normal brains [28], and 8 fresh primary and non cultured GBMs [29], where PATZ1 expression is highly correlated with that of PROM1 (the gene encoding prominin-1/CD133) (Figure 3D), and is significantly enriched in the CD133+ compared to the CD133- subpopulation (Figure 3E).