Folate and alcohol are dietary factors affecting the risk of cancer development in humans. The interaction between folate status and alcohol consumption in carcinogenesis involves multiple mechanisms. Alcoholism is typically associated with folate deficiency due to reduced dietary folate intake. Heavy alcohol consumption also decreases folate absorption, enhances urinary folate excretion and inhibits enzymes pivotal for one-carbon metabolism. While folate metabolism is involved in several key biochemical pathways, aberrant DNA methylation, due to the deficiency of methyl donors, is considered as a common downstream target of the folate-mediated effects of ethanol. The negative effects of low intakes of nutrients that provide dietary methyl groups, with high intakes of alcohol are additive in general. For example, low methionine, low-folate diets coupled with alcohol consumption could increase the risk for colorectal cancer in men. To counteract the negative effects of alcohol consumption, increased intake of nutrients, such as folate, providing dietary methyl groups is generally recommended. Here mechanisms involving dietary folate and folate metabolism in cancer disease, as well as links between these mechanisms and alcohol effects, are discussed. These mechanisms include direct effects on folate pathways and indirect mediation by oxidative stress, hypoxia, and microRNAs.

中文翻译：

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叶酸途径介导乙醇在肿瘤发生中的作用。

叶酸和酒精是影响人类患癌症风险的饮食因素。叶酸状态和饮酒在致癌过程中的相互作用涉及多种机制。由于膳食叶酸摄入量减少，酒精中毒通常与叶酸缺乏有关。大量饮酒还会降低叶酸的吸收，增强尿中叶酸的排泄，并抑制对一碳代谢至关重要的酶。虽然叶酸代谢涉及几个关键的生化途径，但由于甲基供体的缺乏，异常的 DNA 甲基化被认为是叶酸介导的乙醇作用的常见下游靶点。低摄入量提供膳食甲基的营养素和高摄入量酒精的负面影响通常是相加的。例如，低蛋氨酸，低叶酸饮食加上饮酒可能会增加男性患结直肠癌的风险。为了抵消饮酒的负面影响，通常建议增加叶酸等营养素的摄入量，并提供膳食甲基。本文讨论了癌症疾病中涉及饮食叶酸和叶酸代谢的机制，以及这些机制与酒精效应之间的联系。这些机制包括对叶酸途径的直接影响和氧化应激、缺氧和 microRNA 的间接介导。本文讨论了癌症疾病中涉及饮食叶酸和叶酸代谢的机制，以及这些机制与酒精效应之间的联系。这些机制包括对叶酸途径的直接影响和氧化应激、缺氧和 microRNA 的间接介导。本文讨论了癌症疾病中涉及饮食叶酸和叶酸代谢的机制，以及这些机制与酒精效应之间的联系。这些机制包括对叶酸途径的直接影响和氧化应激、缺氧和 microRNA 的间接介导。