Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Post-pregnancy events promote breast tumor metastasis

06.02.2006


Changes in the tissue environment of the breast that occur after pregnancy promote the metastasis of breast tumor cells. The paper by McDaniel et al., “Remodeling of the mammary microenvironment following lactation promotes breast tumor cell metastasis,” appears in the February issue of The American Journal of Pathology and is accompanied by a commentary.



This work also highlights an important shift in thinking about what influences cancers to metastasize: the move from studying specific gene mutations to studying the tumor environment. The focus on the tumor environment, or stroma, has been gaining strength in recent years, as detailed in the commentary by Sonnenschein and Soto.

The human breast undergoes dramatic changes during the course of pregnancy, lactation, and involution (the process by which the milk-producing tissue is reabsorbed and the breast returns to “normal”). These processes require mammary cells to proliferate, differentiate, and finally die, events that are partly driven by changes in the environment surrounding the cells, or extracellular matrix. How these changes affect the outcome of breast cancer is of great interest, especially considering the epidemiological link between breast cancer after pregnancy and poor prognosis.


Under the leadership of Dr. Pepper Schedin, researchers at the AMC Cancer Research Center of University of Colorado Health Science Center compared extracellular matrix from mammary glands of rats exhibiting post-lactation involution to that of virgin rats. They found that the involution matrix contained higher levels of matrix proteases and degraded proteins and generally more matrix proteins than virgin matrix, indicating that involution matrix was undergoing significant structural changes. When immortalized “normal” human breast cells were grown on each type of matrix, only virgin matrix supported formation of mammary duct-like structures, further demonstrating signaling differences inherent to the source of matrix.

In vitro invasion assays established that human breast tumor cells migrated much better through the involution matrix than through virgin matrix. Schedin’s group next performed in vivo experiments to further confirm that post-lactation involution matrix enhances tumor cell migration (i.e. metastasis). Breast tumor cells were mixed with either involution or virgin matrix, and the mixtures were injected into the mammary fat pads of mice. Human tumor cells formed small mammary tumors, regardless of matrix source; however, the involution matrix exerted a more powerful push toward metastasis, with cells spreading to the lung, liver and kidney, expressing higher levels of the human vascular growth factor VEGF and increasing blood vessel development.

These data demonstrate the importance of the changing breast environment in the evolution of breast cancer. Specifically, changes in the extracellular matrix that occur during post-pregnancy involution may actually promote metastasis of breast cancer following pregnancy. The authors further offer that these data may explain why women with breast cancer diagnosed up to 5 years after pregnancy are at greater risk of developing metastases.

Audra Cox | EurekAlert!
Further information:
http://www.asip.org

More articles from Health and Medicine:

nachricht Correct connections are crucial
26.06.2017 | Charité - Universitätsmedizin Berlin

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Study shines light on brain cells that coordinate movement

26.06.2017 | Life Sciences

Smooth propagation of spin waves using gold

26.06.2017 | Physics and Astronomy

Switchable DNA mini-machines store information

26.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>