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:
Green Tea & Tumor Growth (tNOX)
A study done at Purdue University and presented at the 1998 meeting of the American Society for Cell Biology, discovered another major mechanism. The authors, the husband and wife team of Dorothy and James Morre, claim that the main tumor-inhibitory mechanism of green tea may stem from its ability to interfere with the enzyme quinol oxidase, generally referred to as NOX. This enzyme is required for growth by both normal and malignant cells. While normal cells express NOX only when dividing, tumor cells express it all the time. The tumor form of the enzyme is called t-NOX, or tumor-associated NOX. Drugs that inhibit tNOX also inhibit tumor growth. While both black and green tea infusions inhibited tNOX in various cancer lines, green tea was able to achieve these results at much greater dilutions, indicating higher concentrations of the active compound or compounds. By selectively testing for active compounds, the authors of the study concluded that epigallocatechin gallate was the active agent responsible for inhibiting tNOX - while sparing the NOX of healthy cells. Dr. Dorothy Morre stated, "In the presence of epigallocatechin gallate, the cancer cells literally failed to grow or enlarge after division. Then, presumably because they failed to reach the minimum size needed to divide, they underwent programmed cell death, or apoptosis." While the inhibition of ateliers. and of tNOX may be the chief anti-carcinogenic mechanisms of green tea polyphenols, or at least two very important ones, there is little doubt that green tea catechins act along several different pathways and interact with a variety of enzymes to produce their anti-cancer effects. It should also be noted that green tea lowers serum glucose and consequently insulin (this will be discussed in detail in the second article on green tea). Since elevated insulin is a potent growth factor for many kinds of tumors, as well as a pro-inflammatory and immunosuppressive hormone, the lowering of insulin in itself should help prevent cancer or, in cases of existing cancer, slow down its growth.
References: Life Extension Magazine and other studies added.
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