Division of Molecular Oncology, Institute of Experimental Cancer Research, CCC North, Kiel, Germany.
Cancer Sci. 2011 Apr;102(4):728-34. doi: 10.1111/j.1349-7006.2011.01870.x. Epub 2011 Feb 24.
Green tea catechins are considered as possible cancer preventive agents for several cancer types but little is known regarding their effects on pancreatic cancer cells. The best studied catechin and the major polyphenol present in green tea is epigallocatechin gallate (EGCG). In the present study, we investigated the in vitro anti-tumoral properties of EGCG on human pancreatic ductal adenocarcinoma (PDAC) cells PancTu-I, Panc1, Panc89 and BxPC3 in comparison with the effects of two minor components of green tea catechins, catechin gallate (CG) and epicatechin gallate (ECG). We found that all three catechins inhibited proliferation of PDAC cells in a dose- and time-dependent manner. Interestingly, CG and ECG exerted much stronger anti-proliferative effects than EGCG. Western blot analyses performed with PancTu-I cells revealed catechin-mediated modulation of cell cycle regulatory proteins (cyclins, cyclin-dependent kinases [CDK], CDK inhibitors). Again, these effects were clearly more pronounced in CG or ECG than in EGCG-treated cells. Importantly, catechins, in particular ECG, inhibited TNFα-induced activation of NF-κB and consequently secretion of pro-inflammatory and invasion promoting proteins like IL-8 and uPA. Overall, our data show that green tea catechins ECG and CG exhibit potent and much stronger anti-proliferative and anti-inflammatory activities on PDAC cells than the most studied catechin EGCG.
绿茶儿茶素被认为是几种癌症类型的潜在抗癌剂，但关于它们对胰腺癌细胞的影响知之甚少。研究最多的儿茶素和绿茶中主要的多酚是表没食子儿茶素没食子酸酯（EGCG）。在本研究中，我们研究了 EGCG 对人胰腺导管腺癌（PDAC）细胞 PancTu-I、Panc1、Panc89 和 BxPC3 的体外抗肿瘤特性，并与绿茶儿茶素的两种次要成分儿茶素没食子酸酯（CG）和表儿茶素没食子酸酯（ECG）的作用进行了比较。我们发现，三种儿茶素均以剂量和时间依赖的方式抑制 PDAC 细胞的增殖。有趣的是，CG 和 ECG 比 EGCG 发挥更强的抗增殖作用。用 PancTu-I 细胞进行的 Western blot 分析显示，儿茶素介导了细胞周期调节蛋白（细胞周期蛋白、细胞周期蛋白依赖性激酶 [CDK]、CDK 抑制剂）的调节。同样，这些作用在 CG 或 ECG 处理的细胞中比在 EGCG 处理的细胞中更为明显。重要的是，儿茶素，特别是 ECG，抑制了 TNFα 诱导的 NF-κB 激活，从而抑制了促炎和促进侵袭的蛋白质（如 IL-8 和 uPA）的分泌。总的来说，我们的数据表明，绿茶儿茶素 ECG 和 CG 对 PDAC 细胞表现出比研究最多的儿茶素 EGCG 更强的增殖抑制和抗炎活性。
