TP53 and cancer: These molecules are able to activate the wild-type-like p53 function in cancer cells expressing mutant proteins, triggering p53-dependent tumor suppression.31,32 Figure 1d shows that treatment with the p53-reactivators CP-31398 or RITA decreased ROS level in both cancer cells having wild-type p53 (PaCa3) and mutant p53 (Panc1); whereas ROS level in p53-null AsPC1 cells was unaffected by these compounds, suggesting that p53 expression is required for their action.