|« Hormone Therapy Risks Outweigh Bone Benefits||Kids with Earache Do Well with Bone-Muscle Therapy »|
STUDY: Drink that Green Tea
JOURNAL: August 2002 Journal of Nutrition
ABSTRACT: The major angiogenic factor, known as vascular endothelial growth factor (VEGF), was inhibited in a dose dependent fashion by an extract of green tea as well as by its main catechin, EGCG.
COMMENTARY: Angiogenesis refers to the formation of new blood vessels, a process that occurs in healthy tissue but which is also used by tumors to fuel their growth. Inhibition of angiogenesis is currently being explored by cancer researchers as a method of halting tumor growth by starving the tumor nutrients that are delivered via its blood supply.
The green tea extract and EGCG were tested on cultures of healthy human umbilical vein cells and human breast cancer cells. Both extracts were found to significantly decrease the levels of VEGF when the cells of either culture were exposed to a VEGF promoter, compared to cell cultures that did not receive the extract. The green tea extract and the EGCG did not differ significantly in their effects on the cells.
Further experiments by the researchers revealed that the green tea extracts acted on a molecular level to inhibit VEGF transcription, although the authors noted that the inhibition of breast cancer angiogenesis by green tea probably involves several other pathways, through its inhibition of other angiogenic molecules.