摘要AIM To study the relationship between the lipid peroxide (LPO) and superoxide dismutase (SOD) and thepathogenesis of gastrointestinal cancers.METHODS We investigated the SOD activity and LPO levels in blood and mucosa of patients withesophageal (EC), gastric (GC) and colorectal cancer (CC), gastric ulcer (GU) and compared with normalesophagus (NE), stomach (NS) and colon (NC). respectively, 287 patients who underwent endoscopy werestudied. SOD activity of the tissue and blood was determined using SUN's adrenaline auto oxidation method.LPO levels were determined according to YU's method.RESULTS The SOD activity and LPO level in blood and mucosa are shown in the Table 1 (x±Sx).Table 1 SOD and LPO in blood and tissues of patients with gastrointestinal cancers SOD(U／mg protein) LPO(U／mg)Groups n Tissue blood Tissue BloodNormal stomachGastric ulcerGastric cancerNormal esophagusEsophageal cancerNormal colonColon cancer 60 42 43 32 52 28 30 1.90±0.18 0.64±0.40a 0.37±0.24a 1.17±0.70 0.39±0.30a 0.81±0.36 0.31±0.17b 33.70±1.73 25.50±0.67b 27.86±1.02b 30.80±3.78 28.23±10.63 20.97±4.77 19.35±7.32 0.01±0.004 0.05±0.010b 0.06±0.021b 0.014±0.005 0.061±0.033b 0.012±0.003 0.069±0.015b 0.83±0.01 0.11±0.02 0.12±0.03 0.08±0.02 0.11±0.02 0.08±0.03 0.11±0.02aP<0.001, bp<0.01 vs corresponding normal controls, respectively.CONCLUSION SOD activity of the tissue is significantly decreased in EC. GC and CC. LPO levels weresignificantly higher than those of corresponding normal tissue. These results suggest that mucosal SOD andLPO levels are closely related to the pathogenesis of the gastrointestinal cancers.