City of Hope awarded NIH grant to study potential link between environmental factors and breast cancer

The National Institutes of Health has awarded City of Hope a five-year, $4.8 million grant to study the possible role of chemicals in the environment in the development of breast cancer during the menopausal transition in women.

The co-principal investigators on the study are two City of Hope researchers known for their work in the potential connection between breast cancer and environmental factors: Shiuan Chen, Ph.D., professor and chair of the Department of Cancer Biology, and Susan L. Neuhausen, Ph.D., The Morris & Horowitz Families Professor in Cancer Etiology & Outcomes Research.

The grant is funded through the Breast Cancer and the Environment Research Program (BCERP), which is a joint effort co-funded by the National Institute of Environmental Health Sciences and the National Cancer Institute. The goal of BCERP is to support transdisciplinary research to enhance understanding of environmental and genetic factors underlying breast cancer risk.

City of Hope was among six U.S. institutions to receive a BCERP grant, which funds studies on women's health issues. The title of the Chen and Neuhausen project is "Menopausal Transition - A Window of Susceptibility for the Promotion of Breast Cancer by Environmental Exposures."

The study is based on a growing body of evidence supporting the link between environmental factors and breast cancer risk. That evidence suggests there may be specific windows of susceptibility during which a woman's body is more vulnerable to carcinogenic changes in breast tissue. Breast cancer statistics suggest that one such time of vulnerability could be the menopausal transition, when menstrual periods become less regular and eventually cease.

"We believe that during this time, when natural hormone levels are declining, environmental endocrine-disrupting chemicals promote hormone-responsive breast cancers," Chen said.

The City of Hope research team will assess the impact that a class of persistent organic pollutants has on estrogen and progesterone receptors in women going through menopause. The goal is to determine whether two types of compounds - bis-phenol A and polybrominated diphenyl ethers - raise breast cancer risk during this time of transition to menopause. To accomplish this, Chen and Neuhausen will evaluate these processes through in vitro cell line experiments, in vivo mouse models, and observational and biological studies in women in the menopausal transition.

The team will analyze blood samples from women who participated in the California Teachers Study, a cohort of educators followed since 1995 that allows researchers to investigate environmental, genetic, and other factors that may cause cancer.

In addition to evaluating blood samples and publishing outcomes, the City of Hope project includes developing resources for educating and engaging the community about environmental exposures and breast cancer risk.