To further elucidate the effects of this difference in catalase in cancer cells vs. normal cells against IR or IR P-AscH− treatment, we used catalase CRISPR/Cas9 KO plasmid knockouts of MIA PaCa-2 and PANC-1 cells (MIA CAT KO and PANC-1 CAT KO). The gene discussed is CAT; the disease is cancer.