a Key Laboratory of Food Processing Technology and Quality Control in Shandong Province, College of Food Science and Engineering , Shandong Agricultural University , Taian , People's Republic of China.
b Barbara Ann Karmanos Cancer Institute, Departments of Oncology , Pharmacology and Pathology, Wayne State University School of Medicine , Detroit , MI , USA.
Expert Opin Drug Discov. 2018 Jul;13(7):643-660. doi: 10.1080/17460441.2018.1465923. Epub 2018 Apr 24.
Increasing evidence has expanded the role of green tea from a traditional beverage to a source of pharmacologically active molecules with diverse health benefits. However, conclusive clinical results are needed to better elucidate the cancer-preventive and therapeutic effects of green tea polyphenols (GTPs). Areas covered: The authors describe GTPs' chemical compositions and metabolic biotransformations, and their recent developments in drug discovery, focusing on their cancer chemopreventive and therapeutic effects. They then review the recent development of GTP-loaded nanoparticles and GTP prodrugs. Expert opinion: GTPs possess potent anticarcinogenic activities through interfering with the initiation, development and progression phases of cancer. There are several challenges (e.g. poor bioavailability) in developing GTPs as therapeutic agents. Use of nanoparticle-based delivery systems has provided unique advantages over purified GTPs. However, there is still a need to determine the actual magnitude and pharmacological mechanisms of GTPs encapsulated in nanoparticles, in order to address newly emerging safety issues associated with the potential 'local overdose' effect. The use of Pro- epigallocatechin gallate (Pro-EGCG) as a prodrug appears to offer improved in vitro stability as well as better in vivo bioavailability and efficacies in a number of animal studies, suggesting its potential as a therapeutic agent for further study and development.
越来越多的证据表明，绿茶已不仅仅是一种传统的饮品，其所含的具有多种健康益处的药理活性分子也具有重要的药用价值。然而，还需要确凿的临床研究结果来更好地阐明绿茶多酚（GTP）的防癌和治疗作用。
作者描述了 GTP 的化学成分和代谢生物转化，以及它们在药物发现方面的最新进展，重点介绍了它们的防癌和治疗作用。然后，他们回顾了 GTP 负载的纳米粒子和 GTP 前药的最新发展。
GTP 通过干扰癌症的起始、发展和进展阶段，具有很强的抗癌活性。将 GTP 开发为治疗剂存在一些挑战（例如生物利用度差）。基于纳米粒子的递送系统的使用为纯化 GTP 提供了独特的优势。然而，仍然需要确定封装在纳米粒子中的 GTP 的实际幅度和药理机制，以解决与潜在的“局部过量”效应相关的新出现的安全问题。作为前药的表没食子儿茶素没食子酸酯（Pro-EGCG）的使用似乎提供了更好的体外稳定性以及更好的体内生物利用度和功效，在一些动物研究中，这表明它有作为治疗剂进一步研究和开发的潜力。
