Expression of Foxo3a, p38, and HSP90 in Caco-2 and D-Caco-2 cells treated for 48 h with 5-FU. The cells were incubated with 500 nM of 5-FU, and the protein expression was evaluated by Western blotting. All the experiments were performed at least three times with similar results. The graphs show the summary data (as % of expression in untreated cells), normalized to γ-tubulin expression after 48 h of treatment with 5-FU. Data shown are means ± SEM (; , ).