Almondes Kaluce Gonçalves de Sousa, Leal Greisse Viero da Silva, Cozzolino Silvia Maria Franciscato, Philippi Sonia Tucunduva, Rondó Patrícia Helen de Carvalho
School of Public Health, Universidade de São Paulo, São Paulo, SP, Brazil.
Rev Assoc Med Bras (1992). 2010 Jul-Aug;56(4):484-8. doi: 10.1590/s0104-42302010000400025.
Evidence has shown that metabolic disorders are common in tumor cells, leading to increased oxidative stress. The increase in the production of reactive oxygen species (ROS) associated with low antioxidant activity has been related to several types of cancer. Selenium, an antioxidant micronutrient, may function as an antimutagenic agent, preventing the malignant transformation of normal cells. A review of the literature was conducted based on a survey of articles published between 2000 and 2009 in the PubMed database; 39 articles that analyzed the relationship between cancer, oxidative stress and selenium supplementation were selected. The protective effect of this mineral is especially associated with its presence in the glutathione peroxidase and thioredoxin reductase, enzymes that are known to protect DNA and other cellular components against oxidative damage caused by ROS. Several studies have shown reduced expression of these enzymes in various types of cancer, especially when associated with low intake of selenium, which may increase the damage. Selenium supplementation appears to reduce the risk of some types of cancer by reducing oxidative stress and DNA damage. However, further studies are needed to clarify the adequate dose of selenium for each situation (sex, geographic location, and type of cancer).
有证据表明，代谢紊乱在肿瘤细胞中很常见，会导致氧化应激增加。与低抗氧化活性相关的活性氧（ROS）生成增加与多种癌症有关。硒是一种抗氧化微量营养素，可能作为抗诱变剂发挥作用，防止正常细胞发生恶性转化。基于对2000年至2009年在PubMed数据库中发表的文章的调查进行了文献综述；选择了39篇分析癌症、氧化应激与补充硒之间关系的文章。这种矿物质的保护作用尤其与其在谷胱甘肽过氧化物酶和硫氧还蛋白还原酶中的存在有关，这些酶已知可保护DNA和其他细胞成分免受ROS引起的氧化损伤。多项研究表明，这些酶在各种类型的癌症中表达降低，尤其是与低硒摄入量相关时，这可能会增加损伤。补充硒似乎通过降低氧化应激和DNA损伤来降低某些类型癌症的风险。然而，需要进一步研究以明确每种情况（性别、地理位置和癌症类型）下的适当硒剂量。
