Defective cell surface 'glue' is key to tumor invasion
2010-12-14
(Press-News.org) A remarkable discovery into how tumour cells invade normal tissue should lead to vital diagnostic tools and help develop strategies to stop the spread of cancer cells. A new study by scientists at the Montreal Neurological Institute and Hospital of McGill University reveals that the surface of aggressive tumour cells lack the strong molecular 'glue' responsible for binding normal cells together. This allows tumour cells to break away, detach from their neighbors, and spread to other regions of the body.
Certain proteins, called cadherins, are located on the surface of cells and play a vital role in cell adhesion or 'gluing' cells together, ensuring the proper organization of tissue. What happens to the cells and the 'glue' that binds them in tumour growth and metastases is poorly understood. "We were concerned that previous research showed that N-cadherin, an adhesive molecule, was important for both normal tissue organization, as well as tumour metastasis," says Dr. David Colman, Director of The Neuro and corresponding author of the study. "We therefore decided to further investigate this apparent paradox."
The team studied the levels of N-cadherin on tumour cell surfaces. "Our study shows that a non-adhesive form of N-cadherin, termed proNcad is present in a much higher proportion on the surfaces of the most invasive melanoma, brain tumour cells, breast cancer and prostate tumour cells, compared to less invasive tumour cells." says Dr. Deborah Maret, research associate and lead author. This non-adhesive form of N-cadherin never reaches the cell surface in normal tissues.
"It appears that although total N-cadherin levels remain constant, the higher levels of the non-adhesive proNcad promote detachment, tumor cell migration and invasion," adds Dr. Maret. "This supports an overall conclusion that non-adhesive (proNcad) and adhesive (Ncad) forms of cadherins co-exist on tumour cell surfaces, but it is the ratio between these functionally opposite molecules that directly dictates the invasion potential of tumour cells." Because the differences between the two forms of cadherin are so small, previous studies have missed detecting the non-adhesive proNcad form on tumour cell surfaces. Hence it was assumed that all Ncad on the tumour cell surface was of the adhesive type. "We were astounded that this was not the case at all," says Dr. Colman.
"As a brain tumour surgeon, I know that stopping cancer cells from migrating is critical for patient survival," says Dr. Rolando Del Maestro, Director of The Brain Tumour Research Centre and a co-author on the study. "We are determined to improve treatment options for patients. We have already introduced new neurosurgical methods and technologies that are unique in North America and are spearheading multidisciplinary initiatives to advance brain tumour research."
Determining the ratios of Ncad and proNcad on the cell surface may serve as a tremendously valuable tool for the staging and progression of malignant tumors. The findings may also shed light on new treatment strategies to arrest the metastatic spread of invasive tumor cells.
INFORMATION:
The study was published in this week's issue of the journal Neoplasia, and was funded by the Canadian Institutes of Health Research; a Richard H Tomlinson Doctoral Fellowship; the Maggie De Fontes Foundation; the Brain Tumour Foundation of Canada; the National Institutes of Health, The Raymonde and Tony Boeckh Fund, Goals for Lily Fund, the Alex Pavanel Family Fund, and the Franco Di Giovanni Brain Tumor Research Fund.
About the Montreal Neurological Institute and Hospital
The Montreal Neurological Institute and Hospital — The Neuro, is a unique academic medical centre dedicated to neuroscience. The Neuro is a research and teaching institute of McGill University and forms the basis for the Neuroscience Mission of the McGill University Health Centre. Founded in 1934 by the renowned Dr. Wilder Penfield, The Neuro is recognized internationally for integrating research, compassionate patient care and advanced training, all key to advances in science and medicine. Neuro researchers are world leaders in cellular and molecular neuroscience, brain imaging, cognitive neuroscience and the study and treatment of epilepsy, multiple sclerosis and neuromuscular disorders. The Montreal Neurological Institute was named as one of the Seven Centres of Excellence in Budget 2007, which provided the MNI with $15 million in funding to support its research and commercialization activities related to neurological disease and neuroscience.
ELSE PRESS RELEASES FROM THIS DATE:
2010-12-14
DURHAM, N.C. – A key focus of the health care debate has involved immigrants and their impact on the U.S. health care system.
A new study shows that Mexican Americans most integrated into the culture -- including those born in the United States -- are more likely to require resources to manage their health conditions than more recent immigrants to the U.S., according to researchers at Duke University, Rice University and the University of Colorado Denver.
"The implications of these findings run counter to the popular belief that recent immigrant arrivals are taxing ...
2010-12-14
HOUSTON -- (Dec. 13, 2010) -- European and U.S. physicists this week are offering up the strongest evidence yet that magnetism is the driving force behind unconventional superconductivity. The findings by researchers from Rice University, the Max Planck Institute for Chemical Physics of Solids (MPI-CPfS) in Dresden, Germany, and other institutions were published online today in Nature Physics.
The findings follow more than three decades of research by the team that discovered unconventional superconductivity in 1979. That breakthrough, which was led by MPI-CPfS Director ...
2010-12-14
Boston, Mass. - In a paper that suggests a new strategy to prevent asthma, scientists at Children's Hospital Boston and their colleagues report that the influenza virus infection in young mice protected the mice as adults against the development of allergic asthma. The same protective effect was achieved by treating young mice with compound isolated from the bacterium Helicobacter pylori (H. pylori), a bacterium that colonizes the stomach and is best known for causing ulcers and increasing the risk of gastric cancers.
The findings, published online December 13 in the ...
2010-12-14
BOZEMAN, Mont. -- New research indicates that the speed of early forest clearance following human colonisation of the South Island of New Zealand was much faster and more intense than previously thought.
Charcoal recovered from lake-bed sediment cores show that just a few large fires within 200 years of initial colonization destroyed much of the South Island's lowland forest. Grasslands and shrubland replaced the burnt forest and smaller fires prevented forests from returning.
The findings - by an international team led by Dave McWethy and Cathy Whitlock from Montana ...
2010-12-14
WASHINGTON – Losing a job is a profoundly distressing experience, but the unemployed may be more resilient than previously believed – the vast majority eventually end up as satisfied with life as they were before they lost their jobs, according to a new analysis published by the American Psychological Association.
"Unemployment rates continue to be historically high in the United States and other countries," said the study's lead author, Isaac Galatzer-Levy, PhD, who is now at New York University School of Medicine. "There's a real concern that this will have long-term ...
2010-12-14
For the first time ever, scientists have found a difference in the way males and females of the same species of vertebrate see things – and that sexes likely use that difference to select their mates.
Queen's PhD candidate Shai Sabbah, a Vanier Scholar, led a team of researchers who found that male and female cichlid fishes not only see things differently, but detect light in different ways as well.
"It is difficult to say what colour attracts the female the most, but we know that if we manipulate the colour of the fish by changing the light in the environment, the ...
2010-12-14
Increased life expectancy in the United States has not been accompanied by more years of perfect health, reveals new research published in the December issue of the Journal of Gerontology.
Indeed, a 20-year-old today can expect to live one less healthy year over his or her lifespan than a 20-year-old a decade ago, even though life expectancy has grown.
From 1970 to 2005, the probability of a 65-year-old surviving to age 85 doubled, from about a 20 percent chance to a 40 percent chance. Many researchers presumed that the same forces allowing people to live longer, including ...
2010-12-14
UCSF researchers have identified an existing medication that restores key elements of the immune system that, when out of balance, lead to a steady decline in immunity and health as people age.
The team found that extremely low doses of the drug lenalidomide can stimulate the body's immune-cell protein factories, which decrease production during aging, and rebalance the levels of several key cytokines – immune proteins that either attack viruses and bacteria or cause inflammation that leads to an overall decline in health.
The initial study, which was designed to define ...
2010-12-14
Early years initiatives for pre-school children are not delivering improvements in language and numeracy development, according to leading education experts.
Experts, conducting one of the largest surveys to date of the development of 117,000 children starting primary school in England over eight years, found that despite a raft of early years' initiatives, such as 'Sure Start', basic levels of development in early reading, vocabulary and maths have remained largely unchanged.
Researchers from the Centre for Evaluation and Monitoring (CEM) at Durham University who ...
2010-12-14
Ann Arbor, Mich.— Expression of a toxic RNA that leads to Fragile X Tremor Ataxia Syndrome is modifiable by genetic or pharmacologic means, according to new research from U-M Medical School scientists.
In the study published online today in the journal Public Library Of Science Genetics, U-M's Peter K. Todd, M.D., Ph.D., led a team of researchers who examined the expression of a toxic messenger RNA (mRNA) seen in the brains of those afflicted with the syndrome.
Fragile X Tremor Ataxia Syndrome (FXTAS) is usually found in older adults, who often have grandchildren afflicted ...
LAST 30 PRESS RELEASES:
[Press-News.org] Defective cell surface 'glue' is key to tumor invasion