si-hVADC1 inhibited cell growth and reduced energy production in GBM cell lines. (A) IHC staining of VDAC1 of human normal brain (n = 13) or GBM (n = 41) in tissue microarray slides (Biomax). Percentages of sections stained at the intensity indicated are shown. (B, C) U-87MG and U-251MG cells were treated for 48 h with si-NT or si-hVDAC1 and analyzed for VDAC1 levels by immunoblotting. (D, E) U-87MG cells were treated with si-NT or si-hVDAC1 (50 nM) and at the indicated time were analyzed for VDAC1 levels (D) or for cell growth using a sulforhodamine B assay (E). (F, G) Mouse primary brain cells (PBCs) were incubated (48 and 72h) with si-NT or si-VDAC1(M/H) and analysed for VDAC1 levels (F) and cell growth (G) (n = 3). (H) U-87MG (black bars) and U-251MG (gray bars) cells were treated with si-NT or si-hVDAC1, transfected 24 h later with pcDNA4/TO, either empty or encoding mVDAC1, and 2 h later, cell growth was analyzed (n = 3). Δ Ψ (I) and ATP (J) levels were analyzed in U-87MG cells (n = 3). FCCP (carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone), **P ≤ .01; ***P ≤ .001 (25 μM) served as control for decreasing Δ Ψ and ATP levels. RU = relative unit.