Figure 5.
Upregulation of death receptors are p53, ERK1/2 and JNK independent. (A) HCT116 (p53 parental and p53 knockout) cells (1 × 106/well) were treated with 15 µM DBA for 24 h. Whole-cell extracts were prepared and analyzed by Western blotting using p53 and DR5 antibodies (Left panel) and p53 antibody (Right panel). The same blots were stripped and reprobed with β-actin antibody to verify equal protein loading. (B) HCT116 cells were treated as indicated above and subjected to Western blotting for phosphorylated Akt1/2, ERK1/2 and JNK (Left panel) and PPARγ (Right panel), (C) CHOP. The same blots were stripped and reprobed with β-actin antibody to verify equal protein loading. (D) HCT116 cells were transfected with CHOP siRNA and control siRNA. After 48 h, cells were treated with 15 µM DBA for 24 h, and whole- cell extracts were prepared for Western blotting (Left panel). Cells were seeded in a chamber slide and transfected with CHOP siRNAs and treated with DBA and TRAIL as indicated above. Cell death was determined by the Live/Dead Assay (Right panel). Green is live and red is dead cells. Percent dead cells are mentioned below the photo.