Featured Research

from universities, journals, and other organizations

Hormones can change the breast's genetic material, study finds

Date:
January 31, 2013
Source:
Walter and Eliza Hall Institute
Summary:
Scientists in Australia have discovered how female steroid hormones can make dramatic changes to the genetic material in breast cells, changes that could potentially lead to breast cancer. Researchers have identified how pregnancy hormones send signals to critical molecules on the DNA to make changes in the epigenome. The epigenome is a series of chemical tags that modify DNA, controlling which genes are switched on and off.

Professor Jane Visvader (right) and Dr Bhupinder Pal discovered that progesterone could radically alter the genetic material of breast cells, causing changes that could potentially lead to breast cancer.
Credit: Image courtesy of Walter and Eliza Hall Institute

Melbourne scientists have discovered how female steroid hormones can make dramatic changes to the genetic material in breast cells, changes that could potentially lead to breast cancer.

Related Articles


Researchers from the Walter and Eliza Hall Institute have identified how pregnancy hormones send signals to critical molecules on the DNA to make changes in the epigenome. The epigenome is a series of chemical tags that modify DNA, controlling which genes are switched on and off.

Professor Jane Visvader, Dr Bhupinder Pal, Professor Geoff Lindeman and colleagues from the institute's breast cancer laboratory led the study, which was published today in Cell Reports.

Professor Visvader said the researchers had created a roadmap of the epigenomes of different breast cell types. In collaboration with Professor Gordon Smyth and colleagues from the institute's Bioinformatics division they determined how the epigenomes changed in response to ovarian hormones such as progesterone.

"We found the epigenome was very sensitive to hormonal regulation," Professor Visvader said. "This reveals another way in which female hormones can influence breast cancer risk -- by altering the epigenome through modifications on the DNA."

The epigenome is where the DNA and the environment intersect, communicating signals from the outside world to the DNA. The epigenome doesn't alter the genetic code, but is a layer of proteins or tags that decorates the DNA and provides instructions on whether DNA should be read and 'switched on' to produce proteins.

The research team found that pregnancy hormones activate a molecule called EZH2, which is an important modifier of the epigenome. "We found that hormones including progesterone activate EZH2 to modify the epigenome, leading to global changes in the expression of a huge number of genes," Professor Visvader said.

"In normal tissue, EZH2 is essential for the development of breast tissue including ducts and milk-producing cells, and for maintaining the activity of breast stem cells and their daughter progenitor cells. However, life-long exposure to hormones could lead to breast tumour initiation through increased levels of EZH2 and the changes that it orchestrates in the epigenome."

Breast cancer is the most common cause of cancer in women, accounting for almost 30 per cent of all cancers affecting women. One in nine women in Australia will develop breast cancer by the age of 85.

High levels of EZH2 are a marker of poor prognosis in breast cancer and have been frequently observed in basal-like breast cancers, the most aggressive types of breast cancer. "The link between progesterone, EZH2 and the epigenome, could be crucially important in the very early stages of breast cancer development," Professor Visvader said.

Professor Lindeman said there were decades of evidence linking hormone exposure with breast cancer, but the hormones' influence on the epigenome was not known. "Our discovery points to a role for hormone-induced changes in the epigenome in the early stages of breast cancer initiation, and could lead to new therapeutics for treating breast cancer," Professor Lindeman said. "Inhibitors against EZH2 are being developed by others, but it will be several years before we know the outcome of these on cancer."

This project was supported by the National Health and Medical Research Council of Australia, the Victorian Government through funding of the Victorian Breast Cancer Research Consortium, the National Breast Cancer Foundation, and the Australian Cancer Research Foundation.


Story Source:

The above story is based on materials provided by Walter and Eliza Hall Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Bhupinder Pal, Toula Bouras, Wei Shi, François Vaillant, Julie M. Sheridan, Naiyang Fu, Kelsey Breslin, Kun Jiang, Matthew E. Ritchie, Matthew Young, Geoffrey J. Lindeman, Gordon K. Smyth, Jane E. Visvader. Global Changes in the Mammary Epigenome Are Induced by Hormonal Cues and Coordinated by Ezh2. Cell Reports, 2013; DOI: 10.1016/j.celrep.2012.12.020

Cite This Page:

Walter and Eliza Hall Institute. "Hormones can change the breast's genetic material, study finds." ScienceDaily. ScienceDaily, 31 January 2013. <www.sciencedaily.com/releases/2013/01/130131144446.htm>.
Walter and Eliza Hall Institute. (2013, January 31). Hormones can change the breast's genetic material, study finds. ScienceDaily. Retrieved April 1, 2015 from www.sciencedaily.com/releases/2013/01/130131144446.htm
Walter and Eliza Hall Institute. "Hormones can change the breast's genetic material, study finds." ScienceDaily. www.sciencedaily.com/releases/2013/01/130131144446.htm (accessed April 1, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, April 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

7-Year-Old Girl Gets 3-D Printed 'robohand'

7-Year-Old Girl Gets 3-D Printed 'robohand'

AP (Mar. 31, 2015) — Although she never had much interest in prosthetic limbs before, Faith Lennox couldn&apos;t wait to slip on her new robohand. The 7-year-old, who lost part of her left arm when she was a baby, grabbed it as soon as it came off a 3-D printer. (March 31) Video provided by AP
Powered by NewsLook.com
Solitair Device Aims to Takes Guesswork out of Sun Safety

Solitair Device Aims to Takes Guesswork out of Sun Safety

Reuters - Innovations Video Online (Mar. 31, 2015) — The Solitair device aims to take the confusion out of how much sunlight we should expose our skin to. Small enough to be worn as a tie or hair clip, it monitors the user&apos;s sun exposure by taking into account their skin pigment, location and schedule. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Soda, Salt and Sugar: The Next Generation of Taxes

Soda, Salt and Sugar: The Next Generation of Taxes

Washington Post (Mar. 30, 2015) — Denisa Livingston, a health advocate for the Diné Community Advocacy Alliance, and the Post&apos;s Abby Phillip discuss efforts around the country to make unhealthy food choices hurt your wallet as much as your waistline. Video provided by Washington Post
Powered by NewsLook.com
UnitedHealth Buys Catamaran

UnitedHealth Buys Catamaran

Reuters - Business Video Online (Mar. 30, 2015) — The $12.8 billion merger will combine the U.S.&apos; third and fourth largest pharmacy benefit managers. Analysts say smaller PBMs could also merge. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins