Figure 2
From: Mycobacterium bovis BCG promotes tumor cell survival from tumor necrosis factor-α-induced apoptosis
BCG-induced COP1 regulates p53 expression. (A-C) A549 cells were infected with BCG at the indicated time points and analyzed for COP1 expression by quantitative real time RT-PCR (A) and immunoblotting (B). Alternatively, COP1 promoter activity was measured by luciferase assay (C). (D and E) Transient transfection of A549 cells with COP1 siRNA was performed and treated as indicated. Immunoblotting for p53 (D) and validation of COP1 siRNA by immunoblotting for COP1 (E). (F and G) A549 cells were either transfected with vector (pcDNA3) or COP1 overexpression construct (pcDNA3-COP1) and treated with TNF-α as indicated to assess the expression of p53 (F) and p53-responsive pro-apoptotic genes (G) respectively. (H and I) A549 cells were transfected with either COP1 (H) or co-transfected with COP1 and p53 (I) overexpression constructs and treated as shown. Apoptosis was measured by immunofluorescence microscopy for Annexin V-FITC staining. Panel shows representative immunofluorescence images and quantitation of Annexin V-FITC MFI. Data is representative of mean ± SEM of at least 3 different experiments and all blots are representative of 3 independent experiments. *p < 0.05 (one-way ANOVA), as compared to pcDNA3 transfected, TNF-α treated cells (G and H) or pcDNA3 + p53-pCEP4 transfected cells (I). Med, Medium; NT, non-targeting. Bar, 20 μm.