文章：

茶预防癌症：动物研究、分子机制和人类相关性

Cancer prevention by tea: animal studies, molecular mechanisms and human relevance

原文发布日期：2009-05-14

DOI: 10.1038/nrc2641

类型: Review Article

开放获取: 否

要点：

1. Tea, made from the dried leaves of the plant Camellia sinensis, is the most popular beverage worldwide after water.
2. Tea and tea polyphenols have been shown to inhibit tumour formation and growth in different animal models for human cancer. The inhibition is associated with decreased cell proliferation, increased apoptosis and suppression of angiogenesis.
3. Tea polyphenols are antioxidants, but they can also generate reactive oxygen species. The major polyphenol from green tea, (−)-epigallocatechin-3-gallate, has been shown to bind directly to several receptors and signalling molecules, and to inhibit the functions of key receptors, kinases, proteinases and other enzymes.
4. Epidemiological studies, however, have not yielded conclusive results on the cancer-preventive effect of tea consumption in humans, possibly owing to different confounding factors. Some human cancer prevention trials with green tea polyphenol preparations have shown promising results.
5. Well-designed epidemiological studies and intervention trials are needed to evaluate the cancer-preventive activities of tea and tea polyphenols in humans.
6. Many issues raised and the experience gained from studies on tea and cancer prevention may be applicable to studies on other dietary constituents.

要点翻译：

1. 茶由山茶属植物的干燥叶子制成，是继水之后全球最受欢迎的饮品。
2. 在多种人类癌症动物模型中，茶及其多酚成分已被证实能抑制肿瘤形成与生长，该抑制作用与细胞增殖减少、细胞凋亡增加及血管生成受抑制相关。
3. 茶多酚是抗氧化剂，但也能产生活性氧。绿茶中的主要多酚成分——表没食子儿茶素-3-没食子酸酯，已被证明可直接结合多种受体和信号分子，并能抑制关键受体、激酶、蛋白酶及其他酶的功能。
4. 然而，关于饮茶对人类癌症预防作用的流行病学研究尚未得出确定性结论，这可能与多种混杂因素有关。部分使用绿茶多酚制剂的人类癌症预防试验已显示出积极结果。
5. 需要精心设计的流行病学研究和干预试验来评估茶及茶多酚对人类癌症的预防作用。
6. 茶与癌症预防研究中提出的诸多问题及积累的经验，或可应用于其他膳食成分的研究。

英文摘要：

Extracts of tea, especially green tea, and tea polyphenols have been shown to inhibit the formation and development of tumours at different organ sites in animal models. There is considerable evidence that tea polyphenols, in particular (−)-epigallocatechin-3-gallate, inhibit enzyme activities and signal transduction pathways, resulting in the suppression of cell proliferation and enhancement of apoptosis, as well as the inhibition of cell invasion, angiogenesis and metastasis. Here, we review these biological activities and existing data relating tea consumption to human cancer risk in an attempt to understand the potential use of tea for cancer prevention.

摘要翻译： 

茶提取物，尤其是绿茶和茶多酚，已被证明在动物模型中可抑制不同器官部位肿瘤的形成与发展。大量证据表明，茶多酚，特别是（−）-表没食子儿茶素-3-没食子酸酯（EGCG），可通过抑制酶活性和信号转导通路，从而抑制细胞增殖、增强细胞凋亡，并抑制细胞侵袭、血管生成和转移。本文综述了这些生物学活性，以及关于饮茶与人类癌症风险关系的现有数据，旨在探讨茶在癌症预防中的潜在应用。

原文链接：

Cancer prevention by tea: animal studies, molecular mechanisms and human relevance