Tea, Genes and Their Interactions on Breast Cancer
Creators: name: University Of California Office Of The President
Publisher: name: University of California Office of the President
publisherIdentifier: https://ror.org/00dmfq477
publisherIdentifierScheme: ROR
Year: 2024

description: Through the funding support from CBCRP, we have conducted a large case-control study of breast cancer among Asian-Americans in Los Angeles County. We have, as others, found that risk of breast cancer is reduced in association with soy intake, particularly with childhood intake. There is also some modest risk reduction among women who only started eating soy as adults but this finding is based on limited numbers. We provided the first piece of evidence from epidemiological studies that tea intake, particularly, green tea, may protect against breast cancer. In addition, the tea-breast cancer association may depend on your genetic background. Because the role of tea was not a specific hypothesis in our original study, our questions were relatively crude and limited to current intake pattern. This proposed study has been designed to address some of the gaps in knowledge regarding the role of tea and soy.
 
 
 
 
 
 
 
 The questions we wish to explore include: Does the type of tea matter (green tea vs black tea)? If green tea can be confirmed to be more beneficial than black tea, can this be explained by the differing effects of green tea and black tea on circulating estrogens as suggested by our preliminary findings? How much tea drinking is needed? Is the protection found only among current tea drinkers? Is the protection found primarily among women who possess a certain genetic background, namely, those who are less efficient in eliminating tea products so that they derive the most benefit from drinking tea? Do you get the most benefit if you eat both soy and drink tea? In addition, what is the benefit of eating soy foods as an adult if you are a non-soy consumer during childhood.
 
 
 
 
 
 
 
 We are proposing to continue this case-control study by recruiting an additional 750 breast cancer patients and 750 control subjects. This new dataset will allow us to confirm our tea finding by obtaining more detailed information on lifetime tea drinking habits. The questionnaire data and DNA materials collected in this proposed study will be combined with the large database of information (from over 1200 cases and 1100 controls) in the current study. The combined database will be used to investigate the role of genes involved in the metabolism of tea and soy. This information will give us some clues regarding who may derive the most benefit from these foods. Finally, we plan to use serum samples from postmenopausal control women to confirm a preliminary finding that circulating estrogen levels may be increased in association with black tea but decreased with green tea intake.
 
 
 
 
 
 
 
 This population of Asian-American women in LA County is uniquely suited to address these questions. From our previous study, we have identified tea and soy as two components of the Asian diet which may have contributed, in part, to the traditionally lower risk of breast cancer. However, these results need confirmation with larger sample sizes and with improved assessment of lifetime tea intake. If the beneficial effects of soy and/or tea can be confirmed, these dietary agents can be easily incorporated in the diets across all racial/ethnic populations.