Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New subtype of breast cancer responds to targeted drug

02.03.2010
A newly identified cancer biomarker could define a new subtype of breast cancer as well as offer a potential way to treat it, say researchers at Washington University School of Medicine in St. Louis. Their findings will be published in the March 1 online early edition issue of the Proceedings of the National Academy of Sciences.

The research could further refine what recent breast cancer research has concluded: that breast cancer is not one disease, but many. So far, research has firmly established that at least five subtypes of breast cancer exist, each having distinct biological features, clinical outcomes and responses to traditional therapies.

The biomarker identified by the Washington University researchers is found frequently in breast cancers and especially in those that have poorer outcomes. It stems from overactivation of a gene called LRP6 (low-density lipoprotein receptor-related protein 6), which stimulates an important cell-growth signaling pathway. LRP6 can be inhibited by a protein discovered in the same laboratory, which could become an effective drug against the breast cancer type, the researchers say.

"We found increased expression of the LRP6 gene in about a quarter of breast cancer specimens we examined, and we think LRP6 overexpression could be a marker for a new class of breast cancer," says Guojun Bu, Ph.D., professor of pediatrics and of cell biology and physiology. "In addition, we found that this biomarker is often associated with breast cancers that are either harder to treat or more likely to recur. We already have an agent that seems to be effective against LRP6-overexpressing tumors, which could someday become a therapy for tumors that right now have few treatment options."

The research was conducted primarily by Chia-Chen Liu, a graduate student in the Bu lab, who is a fellow in the Cancer Biology Pathway Program at the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital.

The researchers' analysis of human breast cancer tissue samples found significant increases in LRP6 levels in 20 percent to 36 percent of the tumors. LRP6 was increased more frequently in ER (estrogen receptor)-negative or HER2 (human epidermal growth factor receptor 2)-negative samples. LRP6 was also increased more frequently in so-called triple-negative breast tumor samples, which test negative for ER, HER2 and PR (progesterone receptor).

In general, patients who have triple-negative breast cancers have an increased risk of disease recurrence after initial treatment and a poorer prognosis. Furthermore, although ER-positive and HER2-positive tumors can be targeted with specific therapies, ER-negative and HER2-negative tumors cannot. So it appears that LRP6 overexpression is often associated with tumors that are currently difficult to treat, says Bu.

Research in the lab had earlier discovered a protein that binds to and inhibits LRP6. This study showed that the protein, called Mesd (mesoderm development), was able to slow the growth of breast cancer cells in the laboratory and to inhibit mammary tumor growth in laboratory mice.

Importantly, mice treated with Mesd did not experience any of the known side effects, such as bone lesions, skin disorders or intestinal malfunctions, associated with inhibition of this growth pathway.

"Our work introduces Mesd as a promising antitumor agent that might be further developed for breast cancer therapy," Bu says. "It would be analogous to such successful breast cancer therapies as Herceptin (trastuzumab), which specifically targets HER2-positive breast cancer."

The researchers also found that a small segment of Mesd has the same effect as the larger molecule. This segment, or peptide, is more stable than the whole protein molecule and can be easily synthesized.

The researchers have patented the protein and the peptide through the university's Office of Technology Management. Recently, Raptor Pharmaceutical Corp. licensed Mesd from the university to develop it for clinical use.

Liu C-C, Prior J, Piwnica-Worms D, Bu G. LRP6 overexpression defines a class of breast cancer subtype and is a target for therapy. Proceedings of the National Academy of Sciences. March 1, 2010 (advance online publication).

Funding from the National Institutes of Health and the Siteman Cancer Center supported this research.

Washington University School of Medicine's 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked third in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.

Siteman Cancer Center is the only federally designated Comprehensive Cancer Center within a 240-mile radius of St. Louis. Siteman Cancer Center is composed of the combined cancer research and treatment programs of Barnes-Jewish Hospital and Washington University School of Medicine. Siteman has satellite locations in West County and St. Peters, in addition to its full-service facility at Washington University Medical Center on South Kingshighway.

Gwen Ericson | EurekAlert!
Further information:
http://www.wustl.edu

Further reports about: Barnes-Jewish Cancer HER2 HER2-positive LRP6 Medicine Science TV breast cancer cancer research

More articles from Health and Medicine:

nachricht On track to heal leukaemia
18.01.2017 | Universitätsspital Bern

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

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: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

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...

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

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>