Figure 4

Radio-induced apoptosis and expression of pro-apoptotic proteins in negative control-lentiviral particle (LV-NC) and LV-Zeta cells after γ-irradiation (IR). (a) Apoptotic cell death was measured by flow-assisted cytometry analysis with fluorescein isothiocyanate-conjugated Annexin V/propidium iodide staining at 96 h after IR to determine radio-induced apoptosis in LV-NC^CD133+ and LV-Zeta^CD133+ cells. The lower right quadrant indicates early apoptotic cells, and the upper right quadrant indicates late apoptotic cells. The early apoptotic cells are represented by a quantitative analysis. The results are the mean±s.d. of three independent experiments (**P<0.01). (b) Protein lysates were analyzed by western blot analysis using Bax, cleaved caspase-3 and poly ADP-ribose polymerase (PARP) antibodies in LV-NC^CD133+ and LV-Zeta^CD133+ cells at 96 h after IR. The band densities were quantified with TINA imaging analysis software and normalized to β-actin expression. The data are expressed relative to the density of IR- and were reproduced in three independent experiments (*P<0.05).