p53-mediated apoptosis follows intrinsic mitochondrial pathway. (A) HTet23p53, HTet26p53 and HTet43GFP cells pretreated for 12 h with Cdk2/5 inhibitor followed by Dox with or without OA were further incubated for 48 h and processed for western blotting with Bax, Bcl-2 and PARP antibodies. (B) HTet23p53, HTet26p53 and HeLa cells were treated as mentioned in (A) and incubated with mitotracker deep-red. Cells were fixed and processed for immunofluorescence with Bax antibody. Bar:10 μm. Lower panel shows magnified-view for HTet23p53 cells. (C) HTet23p53 cells were treated as described in (A) and processed for mitochondrial and cytoplasmic fractionation. Western blotting was performed with cytochrome-C antibody. (D) HTet23p53 cells transfected with pTRE or pTREBcl-2 plasmids were treated with 500 ng/ml of Dox for 48 h and processed for western blotting with Bcl-2 specific antibody. β-Actin served as a loading control (inset). HTet23p53, HTet26p53, HTet43GFP and HeLa cells were transfected with pTRE or pTRE2Bcl-2 plasmids and treated with Dox with or without OA and further incubated for 48 h. Cell-viability was determined by MTT. Bars represent variation within the wells of an experiment done twice (± S.E.). *Represents P < 0.01.