TP53 and lung cancer: A similar experiment was performed with p53-null, Fhit-negative lung cancer-derived H1299 D1 and E1 clones carrying PonA-inducible FHIT and empty vector expression plasmids, respectively; the cells were treated with 5 μM PonA and at 48 h treated with 0.5 and 1.0 mM H2O2; the percentage of ROS-positive cells was higher in Fhit-positive D1 cells than in E1 control cells (20% vs. 3.5% at 0.5 mM H2O2, and 78% vs. 25% at 1.0 mM H2O2, respectively) (Fig. 3b).