Mechanisms of growth inhibition of human lung cancer cell line, PC-9, by tea polyphenols
Mechanisms of growth inhibition of human lung cancer cell line, PC-9, by tea polyphenols
复制标题
DOI：
10.1111/j.1349-7006.1997.tb00431.x
复制
发表时间：
1997-07-01
期刊：
影响因子：
--
通讯作者：
Fujiki, H
中科院分区：
文献类型：
--
作者：
Okabe, S;Suganuma, M;Fujiki, H
（-）-表没食子儿茶素没食子酸酯（EGCG）（绿色茶的主要成分）和绿色茶提取物显示出对各种癌细胞系（如肺癌、乳腺癌和胃癌）的生长抑制。我们研究了茶多酚如何诱导癌细胞的生长抑制。由于绿色茶提取物含有各种茶多酚，如EGCG、（-）-表没食子儿茶素（EGC）、（-）-表儿茶素没食子酸酯（EGG）和（-）-表儿茶素（EC），因此首先检查每种茶多酚对人肺癌细胞系PC-9细胞生长的抑制潜力。EGC和ECG对PC-9细胞生长的抑制作用与EGCG相当，而EC对PC-9细胞生长的抑制作用不明显。从细胞周期调控的角度研究了EGCG抑制细胞生长的机制。流式细胞仪分析显示，50 μ M和100 μ M的EGCG处理使G（2）-M期细胞的百分比分别从13.8%增加到15.6%和24.1%。用100 μ M EGCG处理后的DNA直方图与用染料木黄酮处理后的DNA直方图相似，表明EGCG诱导PC-9细胞中的G（2）-M阻滞。此外，我们发现通过显微放射自显影，[H-3]EGCG被纳入细胞质，以及核。这些结果为EGCG和绿色茶提取物作为人类癌症预防剂的作用机制提供了新的见解。
(-)-Epigallocatechin gallate (EGCG), the main constituent of green tea, and green tea extract show growth inhibition of various cancer cell lines, such as lung, mammary, and stomach. We studied how tea polyphenols induce growth inhibition of cancer cells. Since green tea extract contains various tea polyphenols, such as EGCG, (-)-epigallocatechin (EGC), (-)-epicatechin gallate (EGG), and (-)-epicatechin (EC), the inhibitory potential of each tea polyphenol on the growth of a human lung cancer cell line, PC-9 cells, was first examined. EGC and ECG inhibited the growth of PC-9 cells as potently as did EGCG, but EC did not show significant growth inhibition. The mechanism of growth inhibition by EGCG was studied in relation to cell cycle regulation. Flow cytometric analysis revealed that treatment with 50 mu M and 100 mu M EGCG increased the percentages of cells in the G(2)-M phase from 13.8% to 15.6% and 24.1%, respectively. The DNA histogram after treatment with 100 mu M EGCG was similar to that after treatment with genistein, suggesting that EGCG induces G(2)-M arrest in PC-9 cells. Moreover, we found by microautoradiography that [H-3]EGCG was incorporated into the cytosol, as well as the nuclei. These results provide new insights into the mechanisms of action of EGCG and green tea extract as cancer-preventive agents in humans.