Chen Xun, Yu Haining, Shen Shengrong, Yin Junjie
Department of Food Science and Nutrition, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310029, PR China.
J Trace Elem Med Biol. 2007;21(2):125-31. doi: 10.1016/j.jtemb.2006.12.007. Epub 2007 Mar 27.
Green tea has chemo-preventive effects to human carcinoma including prostate cancer. Epigallocatechin gallate (EGCG) is the major active component in green tea. Zn(2+) is indispensable to our health, and plays an important role in the normal function and pathology of the prostate gland, and might be a good marker for diagnosing prostate cancer. Effects of Zn(2+), EGCG and their interactions on the growth of androgen-insensitive prostate cancer cell (PC-3) were investigated in the present paper. The results show that Zn(2+) and EGCG inhibited the growth of PC-3 cells in a time- and dose-dependent manner, but effects of interactions of EGCG with Zn(2+) were extremely dependent on their concentrations and added orders. Inhibitory effects of Zn(2+) were significantly decreased in the presence of EGCG on PC-3 cell growth. Therefore, we hypothesize that complexation of EGCG with Zn(2+) might be responsible for the observed decrease of the bioactivities of Zn(2+) against PC-3 cells.
绿茶对包括前列腺癌在内的人类癌症具有化学预防作用。表没食子儿茶素没食子酸酯（EGCG）是绿茶中的主要活性成分。锌离子（Zn(2+)）对我们的健康不可或缺，在前列腺的正常功能和病理过程中发挥重要作用，可能是诊断前列腺癌的良好标志物。本文研究了锌离子（Zn(2+)）、表没食子儿茶素没食子酸酯（EGCG）及其相互作用对雄激素不敏感前列腺癌细胞（PC-3）生长的影响。结果表明，锌离子（Zn(2+)）和表没食子儿茶素没食子酸酯（EGCG）以时间和剂量依赖性方式抑制PC-3细胞的生长，但表没食子儿茶素没食子酸酯（EGCG）与锌离子（Zn(2+)）相互作用的效果极大地取决于它们的浓度和添加顺序。在表没食子儿茶素没食子酸酯（EGCG）存在的情况下，锌离子（Zn(2+)）对PC-3细胞生长的抑制作用显著降低。因此，我们推测表没食子儿茶素没食子酸酯（EGCG）与锌离子（Zn(2+)）的络合可能是观察到的锌离子（Zn(2+)）对PC-3细胞生物活性降低的原因。
