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Green Tea & Cancer - Read what noted Oncologist Dr. Mitchell Gaynor's has to say about green tea. Select from our updated articles database for specific cancers:
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Green Tea and Metastasis Prevention Date: 01-01-2003 |
Green tea has also been shown to help prevent metastasis. Cancer cells secrete special enzymes called collagenases in order to penetrate and colonize various tissues. It is the metastatic process that is lethal, not the primary tumor. Hence finding substances that can prevent metastasis is of prime importance in fighting cancer. A study done at the University of Shizuoka in Japan found that epigallocatechin gallate does in fact inhibit the secretion of collagenases by tumor cells (in this study, highly metastatic lung cancer cells), thus arresting their ability to invade normal tissue. Black tea theaflavins were also effective. There is also additional evidence that green tea polyphenols help inhibit angiogenesis, or the growth of new blood vessels that nourish the tumor.
Two of the green tea polyphenols, epigallocatechin-3-gallate and epicatechin-3-gallate, have been found to be effective inhibitors of 5 alpha-reductase type I, reducing the synthesis of DHT, a potent form of testosterone implicated in causing prostate enlargement and prostate cancer. Epigallocatechin gallate has also been found to be the most potent catechin in inducing apoptosis in human prostate cancer cells when tested on various cell lines. Together with lycopene and selenium, green tea should be considered as a special prostate-protective agent.
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References: Life Extension Magazine and other studies added.
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