CAT and neoplasm: However, pretreatment with SLENU and following application of BLM, DOX, or R, led to significantly decreased levels of the antioxidant enzyme CAT compared to the groups of tumor bearing mice with BLM, DOX, or R administrated alone (mean 37.199 U/gPr, P < 0.001; 30.409 U/gPr and 33.255 U/gPr, P < 0.00001).