Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protein That Predicts Tamoxifen Resistance is Identified

05.12.2003


Kimberly Blackwell, M.D.


Researchers at the Duke Comprehensive Cancer Center have identified a protein that breast cancer tumors over-produce when they become resistant to the drug tamoxifen. The researchers said their finding could help them predict which tumors will benefit from tamoxifen -- the front-line drug used to treat operable breast cancer -- and which tumors won’t.

Future studies will be able to determine if tumors that over-produce this protein, called MTA-1, could be treated with a different hormonal therapy following their initial treatment with surgery, chemotherapy and/or radiation, said Kimberly Blackwell, M.D., assistant professor of oncology at the Duke Comprehensive Cancer Center.

Blackwell will present her team’s findings on Dec. 4 at the 26th annual San Antonio Breast Cancer Symposium.



Their latest findings supports last year’s discovery, reported at the same annual meeting, in which Blackwell demonstrated that tamoxifen-resistant tumors actually change their cellular characteristics to become responsive to other types of drugs. Blackwell says that elevated levels of MTA-1 represent one of these cellular changes in tumors that stop responding to tamoxifen.

"MTA-1 is just one of the proteins that plays a role in tamoxifen resistance, but it is one important step toward helping us better target our therapies toward each woman’s particular type of tumor," said Blackwell. "Theoretically, we could biopsy women at the time of diagnosis and select an alternative drug to tamoxifen if their tumors over-express MTA-1."

Furthermore, she said, MTA-1 is known to be a predictor of poor prognosis and the potential for breast cancer metastasis, so that testing for its presence prior to treatment could help them devise more aggressive strategies from the outset.

In years past, tamoxifen was the only option to help prevent breast cancers from recurring in women with estrogen-positive tumors, said Blackwell. But a percentage of women develop resistance to the drug.

To better understand this phenomenon, Blackwell and colleagues developed a strain of mice whose tumors eventually became resistant to tamoxifen. Once tamoxifen resistance was achieved, they conducted a gene array analysis to determine which genes were over-expressed in the new tumor line. They identified 20 different such genes, and found that MTA-1 was a gene that was strongly over-expressed in the tamoxifen-resistant tumors.

To date, scientists have found only a few other genes or proteins over-expressed in tamoxifen-resistant tumors, making the new discovery an important one for determining how a tumor will respond to treatment.

"We have a multitude of hormonally based drugs at our disposal that are designed to treat or prevent breast cancer and its recurrence," said Blackwell. "Our ultimate goal is to test tumors at the time of diagnosis to determine what their molecular signatures are and then to select the best therapy aimed at treating the tumor."

Other authors on the research team, all from Duke, include Mark Dewhirst, Ph.D., Donald McDonnell, Ph.D., Holly Dressman, M.D., Stacey A. Snyder, and Jeffrey R. Marks, Ph.D.

Becky Levine | dukemed news
Further information:
http://dukemednews.org/news/article.php?id=7268

More articles from Health and Medicine:

nachricht Penn vet research identifies new target for taming Ebola
12.01.2017 | University of Pennsylvania

nachricht The strange double life of Dab2
10.01.2017 | University of Miami Miller School of Medicine

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: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>