大肠癌抗氧化体系的损伤

Impairment of antioxidant system in human colorectal cancer

目的：探讨自由基与人体大肠癌的关系。方法：通过生物化学方法分别测定了大肠癌组织中超氧化物歧化酶（ＳＯＤ）、过氧化氢酶（ＣＡＴ）、谷胱苷肽过氧化物酶（ＧＳＨ－ Ｐｘ）的活性及脂质过氧化物丙二醛（ＭＤＡ）的含量、微量元素硒（Ｓｅ）的含量、维生素Ｅ的含量。同时采用患者正常粘膜为对照测定上述各项指标。结果：ＳＯＤ、ＣＡＴ、ＧＳＨ－ Ｐｘ 的活性在肿瘤组织中较正常粘膜显著降低（Ｐ＜ ０．０１， Ｐ＜ ０．０５，Ｐ＜ ０．０１）。ＭＤＡ、Ｓｅ 和维生素Ｅ 在肿瘤组织中较正常粘膜显著降低（Ｐ＜ ０．０１，０．０１＜ Ｐ＜ ０．０５，Ｐ＜ ０．０１）。结论：人类大肠癌的抗氧化酶系均有不同程度的损伤，脂质过氧化作用减弱，硒代谢异常。

Objective:To discuss the relation between free radical and human colorectal cancer.Methods:the activity of superoxidodismutase (SOD),Catalase (CAT),glutathion perroxidase (GSH-Px) and the content of malondialdehyde (MDA) product of lipid peroxides,selenium,vitamin E were measured in 39 specimen of coloretal carcinoma tissue and normal colorectal mucosa.Results:The activity of three scavenger enzymes of free radical in tumor were remarkably reduced ( P <0 01,0.01< P <0 05, P <0 01),compared with that of normal mucose.GSH-Px played an important role in three scavengers,the content of MDA,selenium and vitamin E in tumor were lower than that of normal mucosa and showed significantly different ( P <0 01, P <0 05, P <0 01).The value of selenium was correlated with the activity of GSH-Px in neoplastic tissue.Conclusion:These results suggested that antioxidant system of human colorectal carcinoma cell was impaired,so supplementation of selenium and vitamin E maybe benifitial to prevention of human colorectal cancer.