>> Главная

Mechanisms of growth inhibition of human lung cancer cell line, PC-9, by tea polyphenols.

Jpn J Cancer Res 1997 Jul;88(7):639-43    

Okabe S; Suganuma M; Hayashi M; Sueoka E; Komori A; Fujiki H
Saitama Cancer Center Research Institute.

(-)-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 (ECG), 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 microM and 100 microM EGCG increased the percentages of cells in the G2-M phase from 13.8% to 15.6% and 24.1%, respectively. The DNA histogram after treatment with 100 microM EGCG was similar to that after treatment with genistein, suggesting that EGCG induces G2-M arrest in PC-9 cells. Moreover, we found by microautoradiography that [3H]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.

Sitemap

   

Type a keyword and click on the 'Go' button to begin full-text search throughout the site.

 Printer-friendly page

Send page to a friend Send page to a friend

Bookmark this page Bookmark this page

>> Natural Health Care

>> Studies Worldwide

>> "Business With Disease"

>> International Campaign

>> Open Letter Campaign

>> Take Action

>> Features

 © 2019 Dr. Rath Health Foundation Send page to a friend contact Printer-friendly page Help Previous document Top of the page Function not available in this page Back to Homepage