FIGURE 4.

Iron chelators increase phosphorylation of p53 and ATF2 that are downstream targets of JNK and p38 kinases. A, p53 at multiple phosphorylation sites; B, ATF2 (Thr-71) that was significantly increased upon incubation of DMS-53 cells with DFO (250 μm) or Dp44mT (25 μm) over 24 h/37 °C. These targets were identified using the phospho-MAPK antibody array (Table 3) and validated here by Western blotting. The panels and the densitometric analysis are typical experiments from three performed or mean ± S.E. of at least three experiments, respectively. *, p < 0.05; **, p < 0.01; ***, p < 0.001. HU, hydroxyurea; Ani, anisomycin.