The whole set of events—from the generation of primary 1O2, catalase-inactivation, and subsequently, tumour-generated secondary 1O2 (followed by inactivation of more catalase), to apoptosis-induction—has been experimentally investigated and verified both in the case of tumour cells in a solution of H2O2 and NO2‒ [96,97] and for plasma-treated tumour cells [59,60]. This evidence concerns the gene CAT and neoplasm.