Figure 2

RB knockdown increased apoptosis induced by VP-16. (a) Representative images of three independent experiments of TUNEL assay (red) in U87 and GBM95 cells after 24 h of 1 μM VP-16 treatment; experimental groups as indicated. Nuclei were stained with DAPI. Arrows indicate TUNEL-positive cells. Scale bar=10 μm. (b) Representative images of three independent experiments of TUNEL assay (red) in OB1 GSCs cells after 24 h of 30 μM VP-16 treatment; experimental groups as indicated. Nuclei were stained with DAPI. Arrows indicate TUNEL-positive cells. Scale bar=10 μm. (c) Percentage of TUNEL-positive U87 (black bars) and GBM95 (white bars) cells 24 h after 1 μM VP-16 treatment; experimental groups as indicated. **P<0.01 and ***P<0.005 by ANOVA and Tukey’s post test. Data are represented as mean and S.E.M. of three independent experiments. (d) Percentage of TUNEL-positive OB1 cells 24 h after VP-16 treatment in each experimental group indicated. ***P<0.005 by ANOVA and Tukey’s post test. Data are represented as mean and S.E.M. of three independent experiments. (e) Percentage of cleaved caspase-3 positive U87 (black bars) cells 24 h after 1 μM VP-16 treatment; experimental groups as indicated. *P<0,05 by ANOVA and Tukey’s post test. Data are represented as mean and S.E.M. of three independent experiments. (f) Representative phospho-p53 (ser 15) immunoblotting for U87 cells 24 h post-VP-16 treatment; experimental groups as indicated. α-Tubulin was used as loading control