Archive for February, 2012


Tuesday, February 28th, 2012


Cornell University | Tuesday, February 21, 2012

 Carly Hodes

Cancer cells must prepare for travel before invading new tissues, but new Cornell research has found a possible way to stop these cells from ever hitting the road.

Researchers have identified two key proteins that are needed to get cells moving and have uncovered a new pathway that treatments could block to immobilize mutant cells and keep cancer from spreading, said Richard Cerione, Goldwin Smith Professor of Pharmacology and Chemical Biology at Cornell’s College of Veterinary Medicine.

The study, co-authored by graduate student Lindsey Boroughs; Jared L. Johnson, Ph.D. ’11; and Marc Antonyak, senior research associate, is published in the Journal of Biological Chemistry (286:37094-37107).

Most adult cells stay stationary, but the ability for some to move helps embryos develop, wounds heal and immune responses mobilize. When migrating cells go astray they can cause developmental disorders, ranging from cardiovascular disease to mental retardation. Metastasis (the spread of cancer from one part of the body to another) also relies on cell migration. How exactly cancer cells migrate and invade tissues continues to be a mystery. However, Cerione’s lab uncovered a potentially important clue when it noticed that cancer cells gearing up to move would collect a protein called tissue transglutaminase (tTG) into clusters near the cell membrane.

“tTG is turning up in many aspects of human cancer research and seems to be contributing to the process that turns cells cancerous,” said Cerione. “Lindsey and Marc discovered that cells must gather tTG into a specific place in their membrane before they can move. But tTG is usually inactive, and we’ve been trying to understand how a cell gets this protein to the exact right place so that it can be activated to stimulate cell migration.”

Observing breast cancer cells in culture, Cerione’s lab found a missing link in our understanding of cell migration: Cancerous cells become hyperactive invasion vehicles by using tTG together with other proteins like wheels, poking them through the surface to form a “leading edge” that pulls the cell forward. But to get the wheels to the leading edge, it turns out they need another protein to roll them there — a “chaperone” protein called heat-shock-protein-70 (Hsp70).


National Cancer Institute
A diagram illustrates the process of metastisis.

“We’ve known for years that Hsp70 acts as a chaperone to other proteins, ensuring that they assume the right structure and behave properly when a cell is under stress,” said Cerione. “Heat shock proteins have also been implicated in cancer, although scientists have been trying to understand their exact role in cancer. Our research has uncovered a previously unknown role for these chaperones — helping tTG get to the leading edge. tTG must be in this location for cancer to spread.”

When cells become stressed, Hsp70 influences the behavior of their “client” proteins, ensuring they keep the right shape. Cells need chaperones like Hsp70 to ensure that various proteins work correctly and don’t warp, but these same chaperones can help cancer cells spread by helping move tTG to the membrane surface. Using inhibitors that block the function of chaperones, Cerione and his team paralyzed Hsp70s and stopped breast cancer cells in culture from gathering tTG into a leading edge, effectively immobilizing them.

Exactly how Hsp70 gets tTG going remains unknown, but Cerione believes other proteins are involved.

“If we can better understand how Hsp70 influences tTG, we can figure out ways to modulate that interaction to immobilize cancer cells and keep them from becoming invasive,” said Cerione. “We suspect Hsp70 is using a third kind of protein to move tTG, and that’s what we’re trying to figure out now. Finding the next link in this chain of events could have important consequences for preventing cancer migration and metastasis.”

This work was funded, in part, by the National Institutes of Health.

Carly Hodes ’10 is a communication specialist at the College of Veterinary Medicine.

Sourced & published by Henry Sapiecha


Tuesday, February 21st, 2012


Scientists have now developed a free app that tells you the ideal time to take a coffee break to keep you in the “optimal mental alertness zone”.

The free Caffeine Zone iOS app, developed at Penn State University, is designed to help people determine when an extra jolt of caffeine may give them a mental boost and when it could harm sleeping patterns.

Users enter information about their caffeine consumption – how much caffeine they drank or plan to drink, when they consumed it and how fast – and the app combines this with data on the known effects of caffeine on the body to create a graph showing how caffeine will affect their system over time.

Coffee timeEach roast coffee has on average 80-115 milligrams of caffeine; the “optimal mental alertness zone” is 200-400 milligrams. Photo: Quentin Jones

The green bar represents the optimal caffeine zone while the blue bar is where you’ll need to get to before bed.

Drinking a cup of coffee rapidly gives people a spike in mental alertness but too much caffeine can also linger in the bloodstream and cause sleep problems hours later, said the researchers, who unveiled their app at the 2011 Augmented Cognition International Conference.

The app warns you if you’re about to consume a coffee that will put you over the sleep threshold, while it also alerts you if you could do with one more cup.

“Many people don’t understand how caffeine levels in their bloodstream go up and how they go down,” said Frank Ritter, the university’s professor of information sciences and technology, psychology and computer science and engineering.

“It’s important to understand the effect that caffeine can have at these various levels.”

According to the International Coffee Organization, for roast and ground coffees the average amount of caffeine contained in a standard cup ranges from 80-115 milligrams, depending on whether you use the drip method or a percolator.

For instant coffees, the average amount of caffeine per cup is 65 milligrams. A can of Coke has 20-30mg of caffeine, a Red Bull has 80mg and a cup of tea has between 40-120mg.

The scientists said they used peer-reviewed studies to determine that caffeine drinkers are in an “optimal mental alertness zone” when they have between 200 and 400 milligrams of caffeine in their bloodstream. But going above this range can cause nausea and nervousness.

When they want to sleep, drinkers may discover that they have problems when they have more than 100 milligrams of caffeine in their bloodstream.

It takes about an hour for caffeine to reach its full effect in a normal adult and after 5-6 hours you will still have half the caffeine you consumed in your blood stream.

Ultimately, the researchers said the app was designed to help people determine when to modify their caffeine habits.

The study was supported by the US Office of Naval Research. Ritter said the app was especially useful for sailors, who have varying sleep patterns each day.

“If they, and others who drink coffee to stay awake, drink too much coffee on one shift, they may have trouble sleeping,” said Ritter.

“So, the next day, they’ll drink even more coffee and have even more trouble sleeping.”

Sourced & published by Henry Sapiecha


Tuesday, February 21st, 2012


COMPANIES do not have the right to a patent over human gene sequences and genetic mutations because such biological material is a product of nature, a court has been told.

The patient advocacy group Cancer Voices has launched landmark legal action against two biotechnology companies that hold patents over a genetic mutation linked to breast and ovarian cancer, known as BRCA1.

The Federal Court has been asked for the first time to decide if patents granted over segments of human DNA are valid.

The US biotech company Myriad Genetics and the exclusive Australian licensee, Genetic Technologies, have a monopoly right to control the use of the BRCA1 mutation for research and development as well as diagnostic testing.

It was granted on the basis that the process of isolating the gene from the human body in a laboratory constituted an “invention”.

In 2008, Genetic Technologies threatened to invoke its patent by ordering all other laboratories to stop performing BRCA1 diagnostic testing but withdrew after a public backlash. The patent is enforced in the US.

Rebecca Gilsenan, from Maurice Blackburn lawyers, which is running the case pro bono, said isolating a gene from the human body cannot amount to a patentable invention, as it is merely a ”discovery”.

Under Australian law, patents can only be granted over “inventions” which constitute a “manner of manufacture” or “manner of new manufacture”.

The court will have to decide whether a naturally occurring biological material when isolated from its natural environment is a ”manner of manufacture”.

Ms Gilsenan said the plaintiffs would argue there were no material structural or functional differences between a BRCA1 gene that is inside the body and a BRCA1 gene that has been isolated from the body.

However, David Shavin, QC, for Myriad, told the court that when removed from the body and used to predict a person’s predisposition to breast or ovarian cancer, the isolated nucleic acid is, in fact, different to that which exists in the cell.

”We are not seeking to patent the BRACA1 gene,” he said. ”The thing that has been created and isolated … is an artificially constructed state of affairs.”

Cancer Voices says allowing genetic mutations linked to specific diseases to be patented could restrict access to life-saving diagnostic procedures and actively discourage scientific research.

”More and more research is leading to the genetic diagnosis of cancer,” the group’s executive director, John Stubbs, said outside court. ”They are our genes, we want to make sure they and the diagnostic tests that go along with them are protected.”

The second applicant, breast cancer survivor Yvonne D’Arcy, said she has taken legal action as she believes biological material should not be used for profit.

”If you’re really sick and its a genetic form of cancer, then everyone female down the line should be able to get the testing done at a price they can afford and if its patented, it won’t be,” she said.

In 2010, a US District Court ruled the same patent was invalid, but the decision was overturned on appeal last year. The American Council for Civil Liberties has petitioned the US Supreme Court to review the decision.

The hearing before Justice John Nicholas is expected to last up to eight days.

Sourced & published by Henry Sapiecha


Thursday, February 2nd, 2012


We’ve seen what excessive amounts of alcohol can do to the body, remember Nicolas Cage’s performance in Leaving Las Vegas? Cirrhosis of the liver, behavioural changes, and finally complete metabolic shutdown. We know that alcohol in excess is toxic but a group of scientists are claiming that ‘added sugar’ is more detrimental to our health.

Scientists Robert Lustig, Laura Schmidt and Claire Brindis from the University of California, San Francisco are calling for governments worldwide to regulate foods and drinks with ‘added sugar’ as strictly as alcohol and tobacco. They are also calling for the sugary foods to be banned in and around schools, placing age limits on purchases as not only is it taxing to the liver, causing fatty liver disease, and ultimately leading to insulin resistance, but claim it to be the underlying causes of obesity and diabetes.

Dr. Lustig and his colleagues are prompting debate as they argue, citing numerous studies and statistics that indicating that sugar has a bigger impact on public health than alcohol and tobacco, as fructose can trigger processes that lead to a chronic disease pandemic including liver toxicity. They concede that a little is not a problem, but a lot kills — slowly.

Related article: Healthier sugar alternatives

No stranger to making provocative statements, in 2009 Dr. Lustig’s lecture “Sugar: The Bitter Truth,” was posted on YouTube and has been viewed by almost two million people, not bad for a 90-minute discussion on the evils of sugar.

Many health experts are disagreeing with the controversial article published in the journal Nature, such as Dr Alan Barclay, head of research at the Australian Diabetes Foundation. He told Lifehacker that “many of the statements simply do not apply to Australia and on certain issues there is little evidence to support their views. Sugar is not the issue” he said, “it is far more complicated than that.”

Professor Peter Clifton, head of nutritional interventions at Baker IDI Heart and Diabetes Institute says, “sugar is just another form of over-consumed calories — easily available and very palatable but no more metabolically deadly than starch or fat calories and certainly not equivalent to alcohol”. “Alcohol toxicity is not just metabolic — it causes violence and road deaths and sugar in any of its forms cannot compete with this statistic,” he said.

However Lustig does highlight that the level of consumption of sugar is many times higher than what nature intended. As our ancestors found sugar in fruit, unprocessed and only available seasonally, and honey is well guarded by bees.

“Over the past 50 years, consumption of sugar has tripled worldwide. Nature made sugar hard to get; man made it easy,” the authors stated. The World Health Organisation states that worldwide the obese outnumber the undernourished. Will there be commercials made asking for donations to help prevent obese people dying of related disease?

Related article: Salt or sugar: which is worse?

Dr. Lustig and his colleagues may not be seeing their recommendations introduced by governments anytime soon, but as the paper points out, diet related diseases are costing around 75 percent of the total health-care dollars in the U.S., and that possibly regulation of the amount of sugar food and drink industries can add to their products should be introduced.

The article states, “Ultimately, food producers and distributors must reduce the amount of sugar added to foods. But sugar is cheap, sugar tastes good and sugar sells, so companies have little incentive to change.”

Sourced & published by Henry Sapiecha