Figure 1.

Both Pim-1 and HBP1 expression are up-regulated in H₂O₂-induced premature senescent or apoptotic cells. A, U2OS and HeLa cells were treated with or without 150 μm H₂O₂ for 48 h, and 2BS cells were treated with or without 20 μm H₂O₂ for 1 week. Then the cells were stained with Annexin V-FITC and PI, and cell apoptosis was analyzed by FACS. Error bars represent S.D. *, p < 0.05; **, p < 0.01. B, U2OS and HeLa cells were treated as indicated in A, and the expression of the endogenous Pim-1, HBP1, p53, DNMT1, p16, and Bax was measured by Western blotting. C, U2OS, HeLa, and 2BS cells were treated as indicated in A, and then cells were stained for SA-β-gal. Error bars represent S.D. *, p < 0.05; **, p < 0.01. D, 2BS cells were treated as indicated in A, and the protein levels of Pim-1, HBP1, p53, DNMT1, p16, and Bax are shown. GAPDH was used as loading control.