Fig. 4.

Silencing of GRP78 increases glioma cell apoptosis in response to etoposide, cisplatin, and γ-radiation. LNZ308 cells were transfected with control or GRP78 small interfering (si)RNA duplexes. After 3 days, the expression of GRP78 was examined using Western blot analysis (A). Control and GRP78 siRNA-transfected cells were plated in plastic dishes, and cell number was monitored at 24-h intervals (B). Cells were treated with etoposide (100 μM) or cisplatin (30 μM) or irradiated with 2 and 5 Gy. Cell apoptosis was determined following 24 h using propidium iodide staining and fluorescence-activated cell sorting analysis (C), and cleaved caspase 7 was determined by Western blot analysis (D). Cell viability in the irradiated cells was determined using MTT assay (E). The results represent one of four experiments with similar results (A and D) or represent the means ± SE of three independent experiments (B, C, and E). *p < 0.01, **p < 0.001, ***p < 0.005. OD, optical density.