Fig. 10. p53 facilitated the removal of 8-oxo-dG residues from DNA in whole SiHa cells. (A) 48 hours after transfection with negative control plasmid (SiHa/N) or p53 shRNA plasmid (SiHa/sip53), cells were treated with 0.5 mM H2O2 for 1 hour. The cells were washed with fresh medium and then incubated in fresh medium for the indicated times. 8-oxo-dG levels were measured at each time point as indicated and expressed as fold of the control sample. (B) The percentage of remaining 8-oxo-dG residues in cellular DNA was plotted as a function of chase time. The t1/2 value reflects the estimated time for levels of 8-oxo-dG to decrease to 50% of its original level.