Figure 4.

Activation of PI3K/Akt signaling is involved in gelsolin-mediated radioresistance. A, Western blot analysis of indicated proteins in resistant and parental A549 and H460 cells transfected with indicated constructs. Representative blots from 3 independent experiments are shown. B and C, Gelsolin-overexpressing A549 and H460 cells were pretreated with or without LY294002 (20 μmol/L) before radiation exposure. Colony formation assay (B) and apoptosis analysis (C) were performed as described in Materials and Methods. Bar graphs represent means ± standard deviation (SD) from 3 independent experiments. *P < .05 versus control. D, Western blot analysis of Akt phosphorylation in gelsolin-overexpressing A549 and H460 cells with or without LY294002 (20 μmol/L) treatment. Representative blots from 3 independent experiments are shown.