PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Princess Margaret breast cancer research finds new drug target companion prognostic test for hormone therapy resistance

2013-04-02
(Press-News.org) (TORONTO, Canada – April 1, 2013) – A team of international cancer researchers led by Dr. Mathieu Lupien at the Princess Margaret Cancer Centre, University Health Network, has identified the signalling pathway that is over-activated in estrogen receptor (ER)-positive breast cancer cells that are resistant to hormone therapies such as tamoxifen, aromatase inhibitors or fulvestrant.

Resistance to hormone therapy is reported in almost half of ER-positive breast cancer patients and no cure is currently available. The fact that the pathway, called Notch, is a drug target creates hope for a new therapy.

The findings, published online today in PNAS, the Proceedings of the National Academy of Sciences of the United States of America, "provide a new therapeutic target against hormone therapy-resistant breast cancers and a companion test to identify tumours that would become resistant" says Dr. Lupien, a scientist at the Ontario Cancer Institute, the research arm of the cancer centre, and an Assistant Professor in the Department of Medial Biophysics, University of Toronto. He specializes in epigenetics of hormone-dependent cancers – the study of non-genetic determinants of cellular identity that can also be altered to initiate or modify disease.

"In studying the epigenetics of hormone therapy resistance, we discovered that breast cancer cells behave like a chameleon. Indeed, as the chameleon changes its skin colour to camouflage itself and evade predators," says Dr. Lupien, "breast cancer cells change the appearance of their DNA through epigenetics to evade, in this case, hormone therapy." In so doing, hormone therapy-resistant breast cancer cells highlight regions of their DNA related to the Notch pathway.

At the molecular level, the research team characterized the epigenetic appearances of the DNA of drug-resistant and drug-responsive breast cancer cells. The team discovered that the Notch signaling pathway plays the predominant role in drug-resistant breast cancer cells even if cells remain positive for ER.

"This is a highly promising discovery that could rapidly translate in the clinic. Drugs against the Notch pathway are available." says Dr. Lupien. The key will be to test the efficacy of these drugs against hormone therapy resistance in breast cancer.

### The research was funded by the National Cancer Institute, the American Cancer Society and the Ontario Institute for Cancer Research. Dr. Lupien's research is also supported by The Princess Margaret Cancer Foundation.

About the Princess Margaret Cancer Centre, University Health Network The Princess Margaret Cancer Centre and its research arm, Ontario Cancer Institute, which includes The Campbell Family Cancer Research Institute, have achieved an international reputation as global leaders in the fight against cancer and delivering personalized cancer medicine. The Princess Margaret, one of the top five international cancer research centres, is a member of the University Health Network, which also includes Toronto General Hospital, Toronto Western Hospital and Toronto Rehabilitation Institute. All are research hospitals affiliated with the University of Toronto. For more information, go to http://www.theprincessmargaret.ca or http://www.uhn.ca. END



ELSE PRESS RELEASES FROM THIS DATE:

Study examines change in cognitive function following physical, mental activity in older adults

2013-04-02
A randomized controlled trial finds that 12 weeks of physical plus mental activity in inactive older adults with cognitive complaints was associated with significant improvement in cognitive function but there was no difference between intervention and control groups, according to a report published Online First by JAMA Internal Medicine, a JAMA Network publication. An epidemic of dementia worldwide is anticipated during the next 40 years because of longer life expectancies and demographic changes. Behavioral interventions are a potential strategy to prevent or delay ...

'RNA sponge' mechanism may cause ALS/FTD neurodegeneration

2013-04-02
The most common genetic cause of both ALS (amyotrophic lateral sclerosis) and FTD (frontotemporal dementia) was recently identified as an alteration in the gene C9orf72. But how the mutation causes neurodegenerative disease appeared mysterious. Researchers at Emory University School of Medicine have demonstrated that this ALS/FTD mutation may be harmful because it creates an "RNA sponge," soaking up an important regulatory protein that binds RNA. The results were published online Monday in the Proceedings of the National Academy of Sciences, Early Edition. "We think ...

Southern California sagebrush better suited to climate change, UCI study finds

2013-04-02
Irvine, Calif., April 1, 2013 — California sagebrush in the southern part of the state will adjust better to climate change than sagebrush populations in the north, according to UC Irvine researchers in the Department of Ecology & Evolutionary Biology affiliated with the Center for Environmental Biology. The results of their study, which appears online in Global Change Biology, will assist land management and policy decisions concerning coastal sage scrub restoration. California sagebrush (Artemisia californica), also known as "cowboy cologne," is the fragrant gray-green ...

Geosphere adds 2 new special issue themes

2013-04-02
Boulder, Colo., USA – Two new themes: "Geodynamics and Consequences of Lithospheric Removal in the Sierra Nevada, California" and "The 36-18 Ma southern Great Basin, USA, ignimbrite province and flareup: Swarms of subduction-related supervolcanoes " add new content to Geosphere's already dynamic lineup. Also in the April 2013 issue: themes "ANDRILL McMurdo Ice Shelf (MIS) and Southern McMurdo Sound (SMS) Drilling Projects" and "Exploring the Deep Sea and Beyond," plus three individual articles not associated with a specific theme. 1. Theme introduction; 2. Theme introduction; 3. ...

By keeping the beat, sea lion sheds new light on animals' movements to sound

2013-04-02
A California sea lion who bobs her head in time with music has given scientists the first empirical evidence of an animal that is not capable of vocal mimicry but can keep the beat, according to new research published by the American Psychological Association. The study's authors suggest that their findings challenge current scientific theories that an animal's ability to synchronize its movements with sound are associated with the same brain mechanisms that allow for vocal mimicry in humans and some birds such as cockatoos, parrots, and budgerigars. The findings were ...

Crucial step in human DNA replication observed for the first time

2013-04-02
For the first time, an elusive step in the process of human DNA replication has been demystified by scientists at Penn State University. According to senior author Stephen J. Benkovic, an Evan Pugh Professor of Chemistry and Holder of the Eberly Family Chair in Chemistry at Penn State, the scientists "discovered how a key step in human DNA replication is performed." The results of the research will be published in the journal eLife on 2 April 2013. Part of the DNA replication process -- in humans and in other life forms -- involves loading of molecular structures called ...

Successful once, protesters may hesitate to return to streets

2013-04-02
As the long-term impact of the Arab Spring continues to take shape, research from political scientists at Princeton University and New York University warns that the protests that swept across the Middle East and North Africa could mark more of an isolated occurrence than a permanent rise of people power in the region. In a paper published online in January by the American Journal of Political Science, "People Power or a One-Shot Deal? A Dynamic Model of Protest," Princeton politics professor Adam Meirowitz and New York University politics Professor Joshua Tucker lay ...

Researchers are first to use common virus to 'fortify' adult stem cells

2013-04-02
WINSTON-SALEM, N.C. – April 1, 2013 – Using the same strategy that a common virus employs to evade the human immune system, researchers at Wake Forest Baptist Medical Center's Institute for Regenerative Medicine have modified adult stem cells to increase their survival – with the goal of giving the cells time to exert their natural healing abilities. "Basically, we've helped the cells be 'invisible' to the body's natural killer cells, T cells and other aspects of the immune system, so they can survive to promote healing," said Graca Almeida-Porada, M.D., Ph.D., senior ...

Adolescents' poor health behaviors raise risk of heart disease as adults

2013-04-02
U.S. adolescents' high levels of poor health behaviors and unfavorable cardiovascular risk factors may increase their chances of heart disease as adults, according to new research in the American Heart Association journal Circulation. Researchers estimated the current state of cardiovascular health of U.S. adolescents based on the seven cardiovascular health components defined in the American Heart Association's 2020 impact goals, which include both health behaviors and factors: blood pressure, total cholesterol, body mass index (BMI), blood glucose, healthy diet, physical ...

Newly identified tumor suppressor provides therapeutic target for prostate cancer

2013-04-02
LA JOLLA, Calif., April 1, 2013 – Scientists at Sanford-Burnham Medical Research Institute (Sanford-Burnham) have identified how an enzyme called PKCζ suppresses prostate tumor formation. The finding, which also describes a molecular chain of events that controls cell growth and metastasis, could lead to novel ways to control disease progression. Working in close collaboration, the labs of Maria T. Diaz-Meco, Ph.D., and Jorge Moscat, Ph.D., found that PKCζ controls the activation of a pro-tumor gene called c-Myc. Normally, PKCζ's alteration keeps c-Myc ...

LAST 30 PRESS RELEASES:

Extreme drought contributed to barbarian invasion of late Roman Britain, tree-ring study reveals

Antibiotic-resistant E. albertii on the rise in Bangladeshi chicken shops

Veterinary: UK dog owners prefer crossbreeds and imports to domestic pedigree breeds

Study links climate change to rising arsenic levels in paddy rice, increasing health risks

Study indicates that risky surgery after a stroke due to carotid artery stenosis is no longer necessary for majority of patients

Blood pressure: New research shows a changing climate may jeopardise global blood supply

Start of US hunting season linked to increased firearm incidents, including violent crimes and suicide

New system could help reduce unnecessary surgery to prevent strokes

Strongest hints yet of biological activity outside the solar system

Children face ‘lifelong psychological wounds’ from entrenched inequities made worse by pandemic, doctor warns

New research reveals socio-economic influences on how the body regulates eating

Unhealthy metabolic profile sharply increases risk of breast cancer returning and subsequent death from breast cancer among those who have survived the disease

Marine radar can accurately monitor vessel speeds to protect whales, study finds

National Center to Reframe Aging teams up with West End Home Foundation

How do age, sex, hormones and genetics affect dementia biomarkers in the blood?

NSF NOIRLab astronomer discovers oldest known spiral galaxy in the Universe

Iron Age purple dye "factory" in Israel was in operation for almost 500 years, using mollusks in large-scale specialized manufacturing process

Even vegans who get enough total protein may fall short for some essential amino acids

RoboBee comes in for a landing

“Ban-the-Box” policy did not effectively help job applicants with criminal records in one analysis

Sunscreen, clothes and caves may have helped Homo sapiens survive 41,000 years ago

"Big surprise": astronomers find planet in perpendicular orbit around pair of stars

Astronomers find rare twist in exoplanet’s twin star orbit

Crystal clues on Mars point to watery and possibly life-supporting past

Microbes in Brooklyn Superfund site teach lessons on fighting industrial pollution

Porous and powerful: How multidirectional grading enhances piezoelectric plate performance

Study finds dramatic boost in air quality from electrifying railways

Bite-sized chunks of chicken with the texture of whole meat can be grown in the lab

A compact, mid-infrared pulse generator

Sex-based differences in binge and heavy drinking among US adults

[Press-News.org] Princess Margaret breast cancer research finds new drug target companion prognostic test for hormone therapy resistance