DNA DSBs evaluation using phosphorylation of histone H2AX in PCCl3 cells an hour after irradiation (A and B) or addition of H2O2 in the medium (C and D). Phosphorylated (γH2AX) and total histones H2AX were detected with specific antibodies. (A) Western blot showing a dose-dependent effect of irradiation on H2AX phosphorylation. (B) Immunocytochemistry detecting phosphorylated histone H2AX foci (pink spots). (C) Western blot showing dose-dependent effect of H2O2 on H2AX phosphorylation. (D) Immunocytochemistry detecting phosphorylated histone H2AX foci (pink spots). DSBs, double-strand breaks.