CAT and pancreatic neoplasm: In a further study showing in vitro radio-sensitization of pancreatic cancer cells by CNPs, it was proposed that the acidic environment of the irradiated cells may impair the catalase-mimetic activity of CNPs, causing H2O2 accumulation and toxicity (Wason et al., 2013); however, this explanation do not consider that to inhibit the catalase mimetic CNPs activity it is necessary to reach pH ≤ 4, values not compatible with what is found in tissues, even cancerous or irradiated (Corsi et al., 2018).