茶多酚抗癌的流行病学研究进展

Current research of tea polyphenols in cancer prevention

茶在世界各地十分普及,其抗癌作用一直受到人们的关注。茶多酚是茶叶浸出物中含量最高的抗氧化物质。细胞和动物研究均表明,茶多酚能够有效地降低肿瘤发生率、抑制肿瘤细胞增殖以及促进肿瘤细胞凋亡。遗憾的是,人群研究的结果却与之不符。全世界至今虽已有200多项与茶多酚相关的人群研究,但只有1/3的研究表明,基线饮茶量与肿瘤发病风险呈负相关。本文旨在总结与茶多酚相关的肿瘤研究的概况,分析导致人群研究与细胞体外及动物研究结果不一致的主要原因,并对未来的研究方向提出一些建议。本文还总结了最新涌现的一些客观测量生物样品中茶多酚含量的人群研究,并比较了通过不同生物样品和不同测量方法得到的结果之间的差异。

Tea is a popular drink worldwide,and its anticarcinogenic function receivs much attention recently.Tea polyphenols are the most abundant antioxidants found in tea infusion,which has been demonstrated to decrease tumor incidence,inhibit tumor multiplicity,and promote tumor apoptosis in both cellular and animal studies.However,the results from population studies are not consistent.Among over 200 tea-related population studies,only one third revealed a negative association between baseline tea intake and cancer risk.The purpose of this review is to summarize the existing tea-related studies,discuss the possible reasons which lead to the different conclusions between human and non-human studies,and provide several future directions in this area.This paper also reviewes a series of human studies which measured tea polyphenol levels objectively,and makes a comparison of the results of these studies in which different biological fluids and ways of assessment were used.