Soy, DNA Methylation and 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: Non-technical overview of the research topic and relevance to breast cancer: 
 
 
 
 There is now compelling epidemiologic evidence from case-control and prospective cohort studies that regular soy food consumers experience a lower risk of breast cancer development and recurrence. Before this finding can be translated into preventing breast cancer, we must have a better understanding of the underlying mechanisms by which soy may protect against breast cancer. There is growing experimental (e.g. non-human) evidence that soy and other dietary factors may influence breast cancer risk through its impact on gene expression, by influencing which genes are turned on and off (this is referred as “epigenetic mechanisms”). In this proposed study, we will investigate whether soy intake in breast cancer patients influences which genes are turned on and off in their breast tumor tissues (by measuring DNA methylation profiles of these genes). We have chosen to study 7 genes known to have an important role in breast cancer development and are commonly turned off in breast cancer patients; soy has been suggested to affect the activity of these genes.
 
 
 
 
 
 The question(s) or central hypotheses of the research: 
 
 
 
 Does tumor tissue from breast cancer patients who were high soy consumers differ from tumor tissue from breast cancer patients who were low soy consumers in terms of DNA methylation patterns of selected genes important in breast cancer development? In other words, are there differences in which genes (or groups of genes) are turned on or off based on level of soy intake?
 
 
 
 
 
 The general methodology: 
 
 
 
 The overall objective of this study is to explore the association between pre-diagnostic soy intake and DNA methylation profile in breast tumor tissues of 326 Asian American women with breast cancer. These women had participated as cases in a CBCRP funded population-based case-control study in Los Angeles County and for whom we have collected detailed information on lifetime soy food intake and other lifestyle factors. The DNA methylation study will be conducted using previously obtained breast tumor tissue from these patients. The laboratory methods to assess DNA methylation status in this proposed study have been developed by colleagues at the University of Southern California (USC) Epigenome Center.
 
 
 
 
 
 Innovative elements of the project: 
 
 
 
 This project has been designed to bridge a knowledge gap in studies of soy and breast cancer. This study uses a new angle to investigate possible mechanisms by which soy may influence breast cancer risk using human data. To our knowledge, this is one of the first studies to test the soy-DNA methylation hypothesis in breast cancer patients with a wide range of soy food intake during adolescence and adult life so that exposure to soy as well as the timing of soy intake will be investigated. Epigenetic changes are potentially reversible, therefore if we learn that certain tumor suppressor genes are inappropriately silenced or oncogenes are inappropriately turned on by soy’s influence on DNA methylation, this would represent a novel chemo-preventive opportunity to reduce breast cancer development and/or recurrence. 
 
 
 
 
 
 Advocacy involvement and relevance to the human issues associated with breast cancer: 
 
 
 
 We will work closely with Diana Chingos, Chairperson of the Cancer Survivorship Council at the USC/Norris Comprehensive Cancer Center. Dr. Wu and Ms Chingos plan to have regular discussions of this study’s design and execution. Dr. Wu will also receive feedback from the members of the Cancer Survivorship Advisory Council at their monthly meeting. Ms Chingos is committed to disseminating the research findings to the breast cancer advocacy and lay community.