Since the temporal maximum of intracellular [H2O2] (i.e., c1,max) is inversely dependent on the catalase concentration (i.e., [CATFeIII]0) with an increasingly steeper incline for lower catalase concentrations in the regime 10−8≤[CATFeIII]0≤10−7 M (see Figure 2), cancer-like cells would be more vulnerable to a decrease in the catalase concentration than normal-like cells, which are associated with higher values of [CATFeIII]0. This evidence concerns the gene CAT and cancer.