Chen L H, Boissonneault G A, Glauert H P
Department of Nutrition and Food Science, University of Kentucky, Lexington 40506.
Anticancer Res. 1988 Jul-Aug;8(4):739-48.
The influences of vitamin C and vitamin E on cancer reported in the literature are reviewed. Several correlational studies and case-control studies suggest that the consumption of vitamin C-containing foods is associated with lower risk for certain cancers, particularly gastric and esophageal cancer. No definite links between dietary vitamin E and human cancer have been demonstrated. Animal and in vitro studies have shown that vitamins C and E can effectively inhibit the formation of carcinogenic nitrosamines. However, animal studies examining the effects of these two vitamins on other chemically-induced cancers are not conclusive. Vitamin C supplementation has been reported to inhibit skin, nerve, lung and kidney carcinogenesis. Vitamin E has been shown to inhibit skin, liver, oral, ear duct, and forestomach carcinogenesis; and to enhance, to have no effect on, or to inhibit mammary gland or colon carcinogenesis, depending upon the method of administration, the level of dietary selenium or fat, and the species and strain of animals used. Both vitamin C and vitamin E can inhibit mutagenesis and carcinogenesis in vitro. Each of the vitamins has been shown to inhibit tumor cell growth and carcinogen-induced DNA damage. The mechanism of action of the two vitamins against carcinogens is not clearly understood. Several suggested mechanisms of action include modification of the metabolism of polycyclic hydrocarbons, reduction of mutagenic activity and reaction with genotoxic free radicals. It is concluded that the potential usefulness of vitamin C and vitamin E in the prevention and treatment of cancer should not be ignored because under certain experimental conditions these two vitamins exert inhibitory effects on chemical carcinogenesis. More carefully standardized and controlled experiments are required to adequately evaluate this potential.
本文综述了文献中报道的维生素C和维生素E对癌症的影响。多项相关性研究和病例对照研究表明，食用含维生素C的食物与某些癌症，特别是胃癌和食管癌的较低风险相关。尚未证实膳食维生素E与人类癌症之间存在明确联系。动物和体外研究表明，维生素C和维生素E可有效抑制致癌亚硝胺的形成。然而，研究这两种维生素对其他化学诱导癌症影响的动物研究尚无定论。据报道，补充维生素C可抑制皮肤、神经、肺和肾脏的致癌作用。维生素E已被证明可抑制皮肤、肝脏、口腔、耳道和前胃的致癌作用；根据给药方法、膳食硒或脂肪水平以及所用动物的种类和品系，维生素E对乳腺或结肠癌的致癌作用可增强、无影响或抑制。维生素C和维生素E均可在体外抑制诱变和致癌作用。已证明每种维生素均可抑制肿瘤细胞生长和致癌物诱导的DNA损伤。这两种维生素对致癌物的作用机制尚不清楚。几种可能的作用机制包括多环烃代谢的改变、诱变活性的降低以及与基因毒性自由基的反应。结论是，维生素C和维生素E在癌症预防和治疗中的潜在作用不应被忽视，因为在某些实验条件下，这两种维生素对化学致癌作用具有抑制作用。需要更严格规范和控制的实验来充分评估这种潜力。
