SOD1 and neoplasm: SOD catalyses the diminution of superoxide into H2 O2, which has to be eliminated by glutathione peroxidase and/or catalase.[30] A small amount of catalase in tumor cells was reported.[31] The inhibition of SOD and CAT activities as a result of tumor growth were also reported.[32] Similar findings were observed in this study with EAC-bearing mice.