EGCG, a major component of green tea, inhibits tumour growth by inhibiting VEGF induction in human colon carcinoma cells.
EGCG, a major component of green tea, inhibits tumour growth by inhibiting VEGF induction in human colon carcinoma cells.
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DOI：
10.1054/bjoc.2000.1691
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发表时间：
2001-03-23
影响因子：
8.8
通讯作者：
Ellis, L M
中科院分区：
文献类型：
--
作者：
Jung, Y D;Kim, M S;Shin, B A;Chay, K O;Ahn, B W;Liu, W;Bucana, C D;Gallick, G E;Ellis, L M
儿茶素是茶叶中具有抗增殖特性的关键成分。我们在体外研究了绿茶儿茶素对体外培养的HT29人结肠癌细胞胞内信号传导和VEGF诱导的影响，在体内研究了绿茶儿茶素对裸鼠HT29细胞生长的影响。在体外研究中，(-)-表没食子儿茶素没食子酸酯（EGCG），绿茶提取物中最丰富的儿茶素，以剂量依赖性的方式抑制Erk-1和Erk-2的激活。然而，其他茶儿茶素如(-)-表没食子儿茶素（EGC）、(-)-表儿茶素没食子酸酯（ECG）和(-)-表儿茶素（EC）在浓度为30 μM时不影响Erk-1或2的激活。EGCG还能抑制血清饥饿诱导的VEGF表达和启动子活性的升高。在体内研究中，胸腺BALB/c裸鼠皮下接种HT29细胞，并在肿瘤细胞接种后2天开始每天腹腔注射EC（阴性对照）或EGCG，剂量为1.5 mg day - 1mouse - 1mouse。与对照组相比，EGCG抑制肿瘤生长（58%）、微血管密度（30%）和肿瘤细胞增殖（27%），增加肿瘤细胞凋亡（1.9倍）和内皮细胞凋亡（3倍）（所有比较P< 0.05）。EGCG可能通过阻断VEGF的诱导来抑制血管生成，从而发挥至少部分的抗癌作用。©2001癌症研究运动http://www.bjcancer.com
Catechins are key components of teas that have antiproliferative properties. We investigated the effects of green tea catechins on intracellular signalling and VEGF induction in vitro in serum-deprived HT29 human colon cancer cells and in vivo on the growth of HT29 cells in nude mice. In the in vitro studies, (-)-epigallocatechin gallate (EGCG), the most abundant catechin in green tea extract, inhibited Erk-1 and Erk-2 activation in a dose-dependent manner. However, other tea catechins such as (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), and (-)-epicatechin (EC) did not affect Erk-1 or 2 activation at a concentration of 30 μM. EGCG also inhibited the increase of VEGF expression and promoter activity induced by serum starvation. In the in vivo studies, athymic BALB/c nude mice were inoculated subcutaneously with HT29 cells and treated with daily intraperitoneal injections of EC (negative control) or EGCG at 1.5 mg day−1mouse−1starting 2 days after tumour cell inoculation. Treatment with EGCG inhibited tumour growth (58%), microvessel density (30%), and tumour cell proliferation (27%) and increased tumour cell apoptosis (1.9-fold) and endothelial cell apoptosis (3-fold) relative to the control condition (P< 0.05 for all comparisons). EGCG may exert at least part of its anticancer effect by inhibiting angiogenesis through blocking the induction of VEGF. © 2001 Cancer Research Campaign http://www.bjcancer.com