Research Group on Quality, Safety and Bioactivity of Plant Foods, Department of Food Science and Technology, CEBAS-CSIC, Murcia, Spain.
Mol Nutr Food Res. 2015 Jul;59(7):1274-91. doi: 10.1002/mnfr.201400866. Epub 2015 Mar 31.
Colorectal cancer (CRC) remains a major cause of cancer death worldwide. Over 70% of CRC cases are sporadic and related to lifestyle. Epidemiological studies inversely correlate CRC incidence with the intake of fruits and vegetables but not with their phenolic content. Preclinical studies using in vitro (cell lines) and animal models of CRC have reported anticancer effects for dietary phenolics through the regulation of different markers and signaling pathways. Herein, we review and contrast the evidence between preclinical studies and clinical trials (patients with CRC or at risk, familial adenopolyposis or aberrant crypt foci) investigating the protective effects of curcumin, resveratrol, isoflavones, green tea extracts (epigallocatechin gallate), black raspberry powder (anthocyanins and ellagitannins), bilberry extract (anthocyanins), ginger extracts (gingerol derivatives), and pomegranate extracts (ellagitannins and ellagic acid). To date, curcumin is the most promising polyphenol as possible future adjuvant in CRC management. Overall, the clinical evidence of dietary phenolics against CRC is still weak and the amounts needed to exert some effects largely exceed common dietary doses. We discuss here the possible reasons behind the gap between preclinical and clinical research (inconsistence of results, lack of clinical endpoints, etc.), and provide an outlook and a roadmap to approach this topic.
结直肠癌（CRC）仍然是全球癌症死亡的主要原因。超过 70%的 CRC 病例是散发性的，与生活方式有关。流行病学研究表明，CRC 的发病率与水果和蔬菜的摄入量呈反比，但与它们的酚类含量无关。使用体外（细胞系）和 CRC 动物模型的临床前研究报告称，膳食酚类化合物通过调节不同的标志物和信号通路对 CRC 具有抗癌作用。在此，我们回顾并对比了临床前研究和临床试验（CRC 患者或高危人群、家族性腺瘤性息肉病或异常隐窝病灶）之间的证据，这些研究调查了姜黄素、白藜芦醇、异黄酮、绿茶提取物（表没食子儿茶素没食子酸酯）、黑覆盆子粉（花青素和鞣花单宁）、越橘提取物（花青素）、生姜提取物（姜辣素衍生物）和石榴提取物（鞣花单宁和鞣花酸）对 CRC 的保护作用。迄今为止，姜黄素是最有前途的多酚类化合物，可能成为 CRC 管理的未来辅助剂。总的来说，膳食酚类化合物对 CRC 的临床证据仍然薄弱，发挥一些作用所需的量大大超过了常见的饮食剂量。我们在这里讨论了临床前和临床研究之间差距的可能原因（结果不一致、缺乏临床终点等），并提供了一种方法来探讨这个话题。
