Department of Basic Medical Lessons, Faculty of Health and Caring Professions, Technological Educational Institute of Athens, Athens, Greece.
Eur J Cancer Prev. 2014 Mar;23(2):84-9. doi: 10.1097/CEJ.0b013e328364f23e.
Catechins (flavan-3-oils) are the main flavonoids present in green tea. The potential cancer chemopreventive and therapeutic properties of green tea catechins have been the focus of research efforts in the last two decades. This systematic review aims to generate in vitro and in vivo data on the effect of green tea catechins on breast carcinogenesis. Electronic databases were searched with the appropriate search terms. Existing evidence suggests that green tea catechins modulate breast cell carcinogenesis. The effect of green tea catechins on breast cell carcinogenesis has been investigated in different experimental models and under different experimental conditions, that is, carcinogen investigated, green tea catechin dosage regimen, treatment with green tea extract versus pure synthetic EGCG, and time point of treatment with green tea catechins in relation to the exposure to the carcinogen. Although the effect of green tea catechins was not always statistically significant, the protective effect of green tea catechins was demonstrated in all the trials, suggesting that treatment with green tea catechins should be further investigated in the clinical setting of chemoprevention of high-risk women. However, it should be emphasized that the reported actions of green tea catechins are observed in high concentrations that are difficult to achieve in the clinical setting. This drawback could be overcome by designing green tea catechins with better bioavailability and/or by cotreatment combining breast cancer endocrine treatment with green tea catechins.
儿茶素（黄烷-3-醇）是绿茶中主要的类黄酮。过去二十年的研究重点集中在绿茶儿茶素的潜在癌症化学预防和治疗特性上。本系统评价旨在生成关于绿茶儿茶素对乳腺癌发生的影响的体外和体内数据。使用适当的搜索词搜索电子数据库。现有证据表明，绿茶儿茶素可调节乳腺细胞癌变。已经在不同的实验模型和不同的实验条件下研究了绿茶儿茶素对乳腺细胞癌变的影响，即研究的致癌物、绿茶儿茶素剂量方案、绿茶提取物与纯合成 EGCG 的治疗、以及绿茶儿茶素与致癌物接触的治疗时间点。尽管绿茶儿茶素的作用并不总是具有统计学意义，但所有试验均证明了绿茶儿茶素的保护作用，表明应在高危女性的化学预防临床环境中进一步研究绿茶儿茶素的治疗。然而，应该强调的是，报告的绿茶儿茶素的作用是在难以在临床环境中达到的高浓度下观察到的。通过设计具有更好生物利用度的绿茶儿茶素或通过联合乳腺癌内分泌治疗与绿茶儿茶素的联合治疗，可以克服这一缺点。
