Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Genetic changes in breast tissue caused by pregnancy hormone helps prevent breast cancer

20.04.2005


A full-term pregnancy at an early age is one of the most effective ways to reduce the lifetime risk of breast cancer, according to research pathologist Irma H. Russo, M.D., of Fox Chase Cancer Center in Philadelphia. A number of studies around the world have established that a full-term pregnancy by age 20 reduces breast cancer risk by half.



Previous studies by Russo and colleagues suggest that breast cells reach full maturity--a process called differentiation--only after a full-term pregnancy. Once this process is complete, the cells are less vulnerable to cancer-causing changes. An early pregnancy confers the strongest protection by limiting the time breast cells remain immature.

"A high-susceptibility or high-risk window exists early in life, between the start of ovarian function and the first pregnancy," explained Russo. "During this period, the mammary gland has continuously varying characteristics influenced by ovarian and pituitary hormones. These traits change during pregnancy under the influence of embryonic and placental hormones."


Russo’s laboratory has demonstrated that both pregnancy and a hormone produced during pregnancy, called human chorionic gonadotropin (hCG), inhibit breast cancer in rats. The placental hormone hCG promotes full maturation of breast cells and also wards off cancerous changes in these cells later.

"This led us to postulate that this hormone might be useful for breast cancer prevention in women," Russo said. "Toward this goal, we designed experiments to learn, first, whether the protection conferred by hCG results from genetic changes specific to this hormone and, second, whether a similar genomic signature would result from either pregnancy or ovarian steroid hormones. Richard Wang, Ph.D., a postdoctoral associate in Russo’s laboratory, presented the results of the first study Sunday, April 17 at the 96th Annual Meeting of the American Association for Cancer Research. The study used virgin rats treated with a daily hCG injection compared to untreated virgin rats.

"Our results show that hCG induces permanent genetic changes in the mammary gland that are related to its breast cancer prevention effect," said Wang.

In addition to Irma Russo, Wang’s Fox Chase co-authors include Jose Russo, M.D., director of Fox Chase’s Breast Cancer and the Environment Research Center; research associates Gabriela Balogh, Ph.D., and Fathima Sheriff, M.D.; research technicians Rachael L. Fernbaugh and Patricia A. Russo; and postdoctoral associates Daniel A. Mailo, Ph.D., and Raquel Moral, Ph.D.

The second study compared four groups of rats: a pregnant group, a virgin group treated with hCG, a virgin group treated with the hormones estrogen and progesterone (ovarian steroid hormones) and an untreated group. Daniel Mailo presented the results Tuesday, April 19 at the AACR meeting.

"These data show that both hCG and pregnancy induce permanent genetic changes that do not result from steroid hormones," Mailo said. Mailo’s co-authors include Irma and Jose Russo, Sheriff, Balogh and research technician Rebecca Heulings.

A grant from the National Institutes of Health supported both studies.

Colleen Kirsch | EurekAlert!
Further information:
http://www.fccc.edu

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>