From an article at CancerPage.com:

Researchers have found a way to target cancer cells by injecting tiny particles that will attack only the diseased cells while leaving healthy cells unscathed, according to a study released on Monday.

A team of researchers working at MIT and Brigham and Women’s Hospital in Boston laced tiny particles with lethal doses of chemotherapy and when injected they targeted cancer cells alone.

The team first conducted experiments on cells growing in laboratory dishes and then on mice bearing human prostate tumors, according to the study, published in the online edition of the Proceedings of the National Academy of Sciences.

In the mice, the tumors shrank dramatically and all of the mice survived the study while the untreated control animals did not.

“A single injection of our nanoparticles completely eradicated the tumors in five of the seven treated animals, and the remaining animals also had a significant tumor reduction, compared to the controls,” said Dr. Omid Farokhzad, assistant professor at Brigham and Women’s Hospital and Harvard Medical School.

While all the parts of this new delivery system are known to be safe, it must still be proven safe for humans. The scientists said that further testing is needed on larger animals, and eventually in humans.

Read the whole article.

Tags: cancer | health | news | biotechnology | blog | weblog | healthcare | nanotech | medical breakthroughs

It’s long been known that if you reduce a creature’s caloric intake to 30 or 40% of normal, it tends to live a healthier life that’s about 30% longer than average. In fact, severe calorie restriction is the only life extension technique that’s been proven to work.

But since such severe dieting as a treatment doesn’t work well with humans, scientists have been trying to determine what actually goes on when an organism is on a restricted diet.

According to this article in Scientific American:

Understanding the mechanisms by which calorie restriction works and developing medicines that reproduce its health benefits have been tantalizing goals for decades…. The phenomenon was long attributed to a simple slowing down of metabolism–cells’ production of energy from fuel molecules–and therefore reduction of its toxic by-products in response to less food.

But this view now appears to be incorrect. Calorie restriction does not slow metabolism in mammals, and in yeast and worms, metabolism is both sped up and altered by the diet. [Article authors David A. Sinclair and Lenny Guarente] believe, therefore, that calorie restriction is a biological stressor like natural food scarcity that induces a defensive response to boost the organism’s chances of survival. In mammals, its effects include changes in cellular defenses, repair, energy production and activation of programmed cell death known as apoptosis. We were eager to know what part Sir2 [a gene they’ve found extends the lifespan of yeast cells by 30%] might play in such changes, so we looked first at its role during calorie restriction in simple organisms.

What they learned is that by reducing caloric intake, life extension does occur, but only if the SIR2 gene is present:

Moreover, a fly that overproduces Sir2 has an increased life span that cannot be further extended by resveratrol or calorie restriction. The simplest interpretation is that calorie restriction and resveratrol [a compound that can activate Sir2] each prolong the lives of fruit flies by activating Sir2.

Once they had a handle on what keeps yeast cells and flies alive longer, scientists located a similar gene in mammals called the SIRT1:

Increased Sirt1 in mice and rats, for example, allows some of the animals’ cells to survive in the face of stress that would normally trigger their programmed suicide. Sirt1 does this by regulating the activity of several other key cellular proteins, such as p53, FoxO and Ku70, that are involved either in setting a threshold for apoptosis or in prompting cell repair. Sirt1 thus enhances cellular repair mechanisms while buying time for them to work.

Over the course of a lifetime, cell loss from apoptosis [programmed cell death] may be an important factor in aging, particularly in nonrenewable tissues such as the heart and brain, and slowing cell death may be one way Sirtuins promote health and longevity. A striking example of Sirt1’s ability to foster survival in mammalian cells can be seen in the Wallerian mutant strain of mouse. In these mice, a single gene is duplicated, and the mutation renders their neurons highly resistant to stress, which protects them against stroke, chemotherapy-induced toxicity and neurodegenerative diseases.
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In a more recent study by Christian Néri of the French National Institute of Health and Medical Research, resveratrol and another STAC, fisetin, were shown to prevent nerve cells from dying in two different animal models (worm and mouse) of human Huntington’s disease. In both cases, the protection by STACs required Sirtuin gene activity.

So researchers know that the SIRT genes (Sirtuins) protect cells during calorie restriction, and they think that the increase of NAD levels in the liver during fasting are what activate the Sirt1 gene.

Among the proteins Sirt1 acts on is an important regulator of gene transcription called PGC-1, which then causes changes in the cell’s glucose metabolism. Thus, Sirt1 was found to act both as a sensor of nutrient availability and a regulator of the liver’s response.

Similar data have given rise to the idea that Sirt1 is a central metabolic regulator in liver, muscle and fat cells because it senses dietary variations via changes in the NAD/NADH ratio within cells and then exerts far-reaching effects on the pattern of gene transcription in those tissues.

The authors are currently running tests in their labs to determine whether the SIRT1 gene improves health and increases the life span of mice. Unfortunately, they don’t expect to have conclusive results for at least 20 years.

Nevertheless, those of us already alive could live to see medications that modulate the activity of Sirtuin enzymes employed to treat specific conditions such as Alzheimer’s, cancer, diabetes and heart disease. In fact, several such drugs have begun clinical trials for treatment of diabetes, herpes and neurodegenerative diseases.

Read the whole article.

Tags: longevity | life extension | science | news | blog | weblog

Exubera inhalable insulin

If you’re a diabetes sufferer who takes insulin, here’s some good news: Exubera, a dry powder insulin that is inhaled rather than injected will soon be available in Britain according to an EDP Business article:

Hank McKinnell, Pfizer chairman and chief executive officer, said: “Exubera is a major, first-of-its-kind, medical breakthrough that marks another critical step forward in the treatment of diabetes, a disease that has taken an enormous human and economic toll worldwide.”

Simon O’Neill, director of care at the charity Diabetes UK, said: “Being able to replace some of the daily insulin injections with an inhaler will be a great breakthrough for some people with type one and type two diabetes. It could prove to be one of the biggest steps forward since the discovery of insulin in 1922.

“We are pleased that after a thorough investigation of the safety and efficacy information available, the EMEA has said that the product can be marketed.

“We hope that when the National Institute of Clinical Excellence comes to review inhaled insulin, it takes into account the potential benefits to people’s quality of life.”

Pfizer and Bespak are also hoping to gain approval for the drug in the United States, another huge market.

A decision is expected soon, with an advisory committee last September recommending the US Food and Drug Administration should approve it.

According to the World Health Organization, diabetes affects about 48 million people in Europe, including two million people in Britain.
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Exubera, which is inhaled before meals, mimics the normal physiological insulin response to eating. It is absorbed into the blood quickly and reduces meal-related spikes in glucose levels in people with diabetes.

Scientists develop heart tissue in a test-tube

Also in the news comes a report that scientists at Dundee University in Scotland have:

[Developed] patches of tissue to mend damaged hearts, which could prevent heart attack victims from having to spend the rest of their lives on medication. A team from Dundee University have successfully grown a tube of heart tissue using cells from newborn rats. The tube beat like a heart, pulsed faster when adrenaline was applied and responded to medicine like a normal organ.

[Source: Scotsman.com News]

Here’s a bit more info on the story from the Pakistan Daily Times:

Dr Keith Baar said he hoped the development could transform the lives of thousands of people left crippled by cardiac arrests. Covering a cardiac patient’s damaged section of heart with a patch grown from their own cells would prove an efficient alternative to putting them on a waiting list for a heart transplant.

Tags: drugs | health | news | personal | medicine | blog | weblog | pharma | healthcare | exubera | diabetes | heart surgery | medical breakthroughs

Scientists at the National Taiwan University have bred fluorescent green pigs for use in stem cell research. Normal pig embryos were injected with a genetically modified protein from jellyfish, resulting in pigs that look like refugees from The Emerald City.

“There are partially fluorescent green pigs elsewhere, but ours are the only ones in the world that are green from inside out. Even their hearts and internal organs are green,” [professor Wu Shinn-Chih] said on Thursday.

The transgenic pigs, commonly used to study human diseases, would help researchers monitor and trace changes of the tissues during the physical development, Wu said.

In 2003, a Taiwan company began selling the world’s first genetically engineered fish, sparking protests by environmentalists who said the fluorescent green fish posed a threat to the earth’s ecosystem.

Read the whole Reuters story.

Yep, green is definitely in fashion when it comes to designer genes!

Tags: science | genetics | biotech | blog | weblog | news

BusinessWeek Online has an article on the blizzard of patents being awarded by the technologically clueless U.S. Patent Office. They describe a patent-everything-in-sight craze in which inventions are being patented that shouldn’t even be considered (because they’re obvious or there’s a lot of prior art) and it’s endangering innovation in the United States.

How to determine when an invention is “obvious” is one of the most critical and contentious issues in patent circles. Over the past two decades, critics say, the hurdle for passing the obviousness test has been steadily lowered, and the U.S. is now awash in a sea of junk patents. Some are just plain silly, such as a patent for “a method [of] exercising and entertaining cats” (basically teasing them with a laser pointer), or another for “an animal toy that a dog may carry in its mouth” (which not only sounds suspiciously like a stick but also looks like one in the patent drawings).
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The tide shows no sign of turning. In 2004, the U.S. Patent & Trademark Office issued 181,000 patents, up from 99,000 in 1990. New applications, meanwhile, are being filed at a rate of about 400,000 per year. If the Patent Office closed its doors today it would need two years just to clear the backlog.

One reason for this explosion is the natural tendency of patents to track broad economic and technological trends. Just as the early 20th century saw the advent of large-scale patenting of chemicals, the past two decades have witnessed the spread of patents on computer software, business methods, and genes. Controversy often accompanies the expansion. For example, critics say many business method patents, for processes that perform operations, are often nothing more than combinations of age-old practices with a computer or the Internet.

In an article in The National Law Journal last month, New York attorney Barry Schindler expressed the current patent-everything-in-sight mentality. Seizing on a recent ruling by a Patent Office administrative board that said method patents don’t even need to make use of technology, he advised companies to “now seek U.S. patent rights for any unique business method covering every conceivable business operation, such as methods of billing clients, hiring employees, marketing products or service…or simply obtaining funding.”

The computer industry has seen plenty of questionable patents lately. Microsoft has received a patent for clicking a mouse button in various patterns, one of them being the double-click that computer users have been doing since Apple introduced the Macintosh in 1984. Then there’s Frank Meyer, a lawyer who realized that nobody had thought to patent the addressing scheme that has been used to access websites and send e-mail on the World Wide Web since the early ’90s, so he patented it in 2003.

The biotech field is seeing similar poaching:

• In 1991, Biocyte patented human umbilical cord cells, so now any doctor wishing to use them in surgery or transfusions must pay royalties.

• Human Genome Sciences (HGS) has patented a human growth hormone gene and has also filed patent applications for more than a million partial human gene sequences.

• Monsanto holds the patent on all genetically-engineered cotton. Belatedly realizing that the patent should never have been granted, the U.S. government has asked the patent office to revoke it.

There are many more examples of patent abuse on the WWW (check out the Electronic Freedom Foundation’s Patent Busting Project for starters).

Tags: economics | computers | biotech | technology | blog | weblog

From a University of Pittsburgh Medical Center news release:

Little Known DNA Repair Enzyme May be a Tumor Supressor Gene

The DNA in our cells is constantly being bombarded by environmental, chemical and cellular insults. Fortunately, our cells contain many enzymes devoted strictly to detecting and repairing any damage caused by these insults. In fact, failure of these enzymes to make needed repairs to genes can lead to the accumulation of mutations and, eventually, cell death or possibly cancer. However, it appears that the activity of some DNA repair enzymes is more critical than others, particularly in developing embryos.

University of Pittsburgh researchers report in the Jan. 1 edition of Cancer Research that a poorly understood enzyme, known as DNA polymerase zeta, or pol zeta, has the uncanny ability to give cells with even heavily damaged DNA a new lease on life. Furthermore, when the enzyme is absent in cells that already have growth control problems, the consequences to chromosomes are catastrophic and may lead to cancer.

“Pol zeta appears to be the only one of a group of specialized DNA polymerases that is critical for development in animals,” explained John P. Wittschieben, Ph.D., research instructor in the department of pharmacology, University of Pittsburgh School of Medicine, and first author of the study. “Moreover, its loss in animal cells plays a significant role in the development of chromosomal instability, which is a hallmark of cancer. Therefore, we believe its function may be to suppress the development of tumors.”

Although DNA polymerases—enzymes responsible for copying, editing and repairing genes and surrounding DNA—generally have the ability to make completely accurate copies of strands of DNA, in certain situations damaged areas, called lesions, can bring this replication machinery to a complete halt. In the last few years, scientists have learned of the existence of a variety of so-called lesion-replicating polymerases that can overcome these replication “stop signs” and keep cells dividing that would otherwise be killed off by their own suicide mechanisms.

First discovered in budding yeast cells, and later in plants and animals, pol zeta has the remarkable ability, in the test tube, to efficiently extend DNA with lesions that stop most other DNA polymerases in their tracks. Other research has shown that inactivation of this lesion-replicating enzyme in yeast leads to a dramatic decrease in the frequency of mutations induced by a wide range of DNA damaging agents.

Read the release.

Tags: cancer | research | science | blog | weblog