Fig 3. Induction of DNA damage by gamma-radiations increases p27^kip1 protein stability.

(A) MCF7 cells were subjected to 0 or 8 Gy or IR. 1h later, cells were fixed and analyzed by immuno-fluorescence microscopy with a p27 antibody and DAPI. (B) MCF7 cells were subjected to 0 (-IR) or 8 Gy (+IR) of IR in the presence of cycloheximide (CHX). Cells harvested at the indicated time points were analyzed by Western blotting with anti-p27 or Actin antibodies. (C) Densitometric quantification of the p27 levels normalized to actin from the Western blot in (B). The data is presented as mean of 3 independent experiments ± SEM. Differences between groups were evaluated using two-tailed Student t tests among replicate experiments; *P < 0.0352; ****P < 0,0001.