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Your Environment. Your Health.

Breast Cancer

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Breast Cancer Awareness: Prevention is the Key

You Can’t Change Your Genes, but You Can Change Your Environment

Given that NIEHS research has clearly established that breast cancer is caused by a combination of genetic, hormonal, and environmental risk factors and we know that environmental factors can be identified and modified, focusing our efforts on prevention presents a tremendous opportunity to stop breast cancer before it starts.

Breast cancer takes a tremendous toll on women and men of all ages, races, and ethnicities, as well as their families and communities.

The National Institute of Environmental Health Sciences (NIEHS) supports research that is helping to discover how our environment may contribute to diseases such as breast cancer.

Once scientists can identify the elements that are associated with cancer risk, appropriate interventions and precautions can be designed for those who are most likely to develop the disease.

IBCRECC Report CoverSome of the biggest news related to breast cancer came this past February, when a federal advisory panel of researchers and advocates released a new report offering recommendations(1MB) for investigating and mitigating environmental causes of breast cancer.

The report, Breast Cancer and the Environment: Prioritizing Prevention(5MB) , issued by the Interagency Breast Cancer and Environmental Research Coordinating Committee (IBCERCC) highlights the need for more emphasis on prevention—not just diagnosis and treatment—and suggests that a national breast cancer prevention strategy be developed that would increase and better coordinate the federal government’s investments in this area.

NIEHS Programs in Breast Cancer Research

NIEHS has played a leadership role in funding and conducting studies on the ways in which environmental exposures increase breast cancer risk.

NIEHS has more than 30 breast cancer research grants, breast cancer research centers, and intramural or in-house research programs investigating human and basic science studies. The National Toxicology Program also conducts research relevant to breast cancer. Much of the NIEHS' work is done in coordination with other institutes and agencies.

NIEHS will continue to work with our federal partners to conduct and support transdisciplinary research that can ultimately lead to interventions earlier in life.
Some examples include:

Sister Study 

Sister Study logoNIEHS, with help from others, has recruited more than 50,000 women to participate in the Sister Study  looking at the possible interplay between genetics and the environment in the development of this disease. The Sister Study includes diverse sisters of women diagnosed with breast cancer from across the country and Puerto Rico. Because of their shared environment, genes, and experiences, studying sisters provides a greater chance of identifying risk factors that may help us find ways to prevent breast cancer.
Some 2013 findings include:

  • Tubal ligation, which is surgery that can close the tubes connecting a woman’s uterus and ovaries, was not found to influence overall breast cancer risk. ( Abstract  )
  • Researchers have discovered DNA methylation in blood cells could prove to be an effective indicator of who will develop breast cancer. ( Abstract  )

Two Sister Study 

Two Sister Study Photo

With funding support from the Susan G. Komen for the Cure  foundation, NIEHS was able to successfully enroll over 1,400 women with young-onset breast cancer and their parents into an offshoot of the Sister Study called the Two Sister Study  . The family-based design is a powerful way to learn about genetic and environmental factors that contribute to breast cancer. The Two Sister Study also allows researchers to make direct genetic and exposure comparisons between sisters who have been diagnosed with breast cancer and their sisters without breast cancer who joined the larger Sister Study.

  • In 2013, the researchers examined the associations between menopausal symptoms and breast cancer in women under age 50. They found that women younger than 50 who had menopause symptoms were less likely to develop breast cancer at a young age. ( Abstract  )
  • We’ve also learned from this study that fertility treatments are not associated with early-onset breast cancer overall, but that women who get pregnant after hormonal fertility treatments are more likely to develop breast cancer than those who use these drugs but did not conceive.( Abstract  )

Breast Cancer and the Environment Research Program

BCERP logoNIEHS and the National Cancer Institute co-fund the Breast Cancer and the Environment Research Program (BCERP), which supports multidisciplinary scientists, clinicians, and community partners studying environmental exposures during puberty in young girls and other windows of susceptibility. These efforts at NIEHS utilize a successful community-based research model, where stakeholders have input into research direction, outcomes, and dissemination of results.

  • The BCERP Windows of Susceptibility Studies are examining how breast cancer risk relates to environmental exposures that occur during periods of human development.
  • The BCERP Puberty Study is tracking more than 1,200 young girls to understand predictions of early puberty that are associated with increased cancer risk.

Partnerships for Environmental Public Health

Environmental Health Chat

PEPH is a network of scientists, community members, educators, healthcare providers, public health officials, and policymakers who share the goal of increasing the impact of environmental public health research at the local, regional, and national level. The Environmental Health Chat podcast recently featured a two-part series about breast cancer and the environment. Tune in to hear experts discuss why breast cancer research is critical for decisions we make in our everyday lives.

National Toxicology Program

NTP logo

The National Toxicology Program  is an interagency program housed at NIEHS whose mission is to evaluate agents of public health concern by developing and applying tools of modern toxicologyIllustrated Dictionary and Resource Directory of Environmental and Occupational Health and molecular biology.

  • The Report on Carcinogens (RoC)  is a congressionally mandated, science-based, public health document that is prepared for the HHS Secretary by the NTP. The report identifies agents, substances, mixtures, and exposure circumstances that are known or reasonably anticipated to cause cancer in humans.
  • The NTP Monograph on Developmental Effects and Pregnancy Outcomes Associated with Cancer Chemotherapy Use During Pregnancy  helps pregnant women diagnosed with cancer and their medical teams make informed decisions about cancer treatment options during pregnancy. The NTP analyzed more than 430 published studies to develop this resource. The monograph includes data and summaries on 56 cancer chemotherapeutic agents for which pregnancy outcomes were reported.

Research on Endocrine Disruptors(1004KB)

Endocrine Disruptors - cover

Understanding how the environment contributes to women’s health is a critical research area being addressed today. As the number of people being diagnosed with diseases such as breast cancer continue to increase, environmental factors, including endocrine disruptors, are likely to play a role. Endocrine disruptors are naturally occurring or man-made substances that may mimic or interfere with the function of hormonesDictionary of Environmental Health in the body. Some studies suggest that exposure to endocrine-disrupting chemicals early in life may increase the risk of developing breast cancer years later.

Moving Forward: NIEHS Strategic Plan

NIEHS Strategic Plan - cover

Research into environmental contributors to disease are a key part of NIEHS' new strategic plan . As laid out in the plan, NIEHS will continue work to study basic mechanisms and windows of susceptibility, and link individual and population exposure to risk using better predictive models and 21st century tools. Also, to enhance diversity in all aspects of research, NIEHS is actively involved in training multidisciplinary scientists. The institute is also enhancing coordination and communication with agencies and other groups.

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