We also tested the E2F1 protein expression in clinical GBM samples using western blot; same as the results of immunohistochemistry, we noticed that the expression of E2F1 was significantly higher in the glioma when compared to NBT, and increased with ascending pathological grade of glioma (p < 0.05, Supplementary Figure S2A). The gene discussed is E2F1; the disease is glioblastoma.