Figure 6. BTG2 reversed the aging phenotype in knockdown SUV39H2 H9C2 cells. (A–B) After transfection of si-BTG2 and control si-NC into H9C2 cells, the cells were collected 48 h later for RT-PCR and western blotting. (C) PLKO-H9C2 and sh-SUV39H2-H9C2 cell lines were cultured in 50 μM H2O2 added with or without siBTG2 for 48 hours. And an SA-β-Gal staining kit was used to detect senescence cells. (D–G) PLKO-H9C2 and sh-SUV39H2-H9C2 cell lines were cultured in normal medium or 50 μM H2O2 medium added with or without siBTG2 for 48 hours. (D) Western blotting for p21 and p53 in mentioned above groups were performed, and the level of β-actin protein was measured as the control. (E) The expression of p21 and p53 in mentioned above groups were quantified by RT-PCR. (F) Flow cytometry was used to quantitatively detect the ROS production of mentioned above groups. (G) The cells in mentioned above groups were fixed and analyzed by immunofluorescence to detect the expression level of γ-H2AX. All the experiments have been repeated independently at least 3 times. *P < 0.05, **P < 0.01, ***P < 0.005 when two groups were compared as indicated, or were compared to the corresponding control.