In the present study, the functions of EGF and bFGF were inhibited using small interfering RNA (siRNA) to interfere with their receptors, and the expression of the markers for stem cells [cluster of differentiation (CD)133], astrocytes (GFAP), neurons [tubulin-β3 (TUBB4)] and oligodendrocytes [myelin basic protein (MBP)] were analyzed for the first time in U251 glioblastoma cells. The gene discussed is GFAP; the disease is glioblastoma.