Figure 8.

Determination of apoptosis and genotoxic stress in lung epithelial cells exposed to hyperoxia, radiation, and double-hit combination challenge. Non-tumorigenic murine alveolar type II epithelial cells (C10) were evaluated after 1 and 2 cycles of hyperoxia and radiation exposure and evaluated by (a) western blotting for GADD45α, cleaved-PARP, cleaved caspase-3, and BAX. Densitometric analysis of band intensity for (b) GADD45α; (c) cleaved-PARP; (d) cleaved caspase-3; and (e) BAX was normalized to β-actin and values are expressed as fold change from CTL. Data are presented as mean ± SEM. * p < 0.05 for each exposure condition as it compares with the unexposed control (CTL) in the same respective time-group; ^# p < 0.05 for significant differences between O₂-alone compared to O₂ + IR; ^§ p < 0.05 for significant differences between IR-alone compared to O₂ + IR.