PROM1 and glioblastoma: Treatment of GBM TSs with 10 μM DFS for 3 weeks significantly reduced the percentage of sphere-positive wells and sphere radii (Fig. 2A), as well as reducing the levels of expression of stemness-related marker proteins, including CD133, Nestin, Sox2, CD44, Msi-1 and PDPN (Fig. 2B).