Miracles and wonders: personal cancer meds

More evidence that the world of medicine is changing in a big way.

Michael Pellini fires up his computer and opens a report on a patient with a tumor of the salivary gland. The patient had surgery, but the cancer recurred. That's when a biopsy was sent to Foundation Medicine, the company that Pellini runs, for a detailed DNA study. Foundation deciphered some 200 genes with a known link to cancer and found what he calls "actionable" mutations in three of them. That is, each genetic defect is the target of anticancer drugs undergoing testing—though not for salivary tumors. Should the patient take one of them? "Without the DNA, no one would have thought to try these drugs," says Pellini.

Starting this spring, for about $5,000, any oncologist will be able to ship a sliver of tumor in a bar-coded package to Foundation's lab. Foundation will extract the DNA, sequence scores of cancer genes, and prepare a report to steer doctors and patients toward drugs, most still in early testing, that are known to target the cellular defects caused by the DNA errors the analysis turns up. Pellini says that about 70 percent of cases studied to date have yielded information that a doctor could act on—whether by prescribing a particular drug, stopping treatment with another, or enrolling the patient in a clinical trial. 

This is only the beginning.

In the future we won't get fat

At the same that we're turning our health care over to bureaucrats in Washington, our scientists are offering a glimpse of the future of medicine. The future is not anything we know now in our so-called "healthcare system," which was not designed as a system and doesn't work as a system. And it's certainly not anything like what Mr. Obama imagines.

In their book Transcend, Ray Kurzweil and Terry Grossman, MD, write:

"We have exactly doubled the amount of the genetic data collected each year since 1990, and this pace has continued since the completion of the Human Genome Project in 2003. The cost of sequencing a base pair of DNA - the building blocks of our genes - has dropped by half each year from $10 per base pair in 1990 to a small fraction of a penny today. Deciphering the first human genome cost a billion dollars. Today, anyone can have it done for $350,000. But, in case that's still out of your budget, just be patient for a little while longer. We are now only a few years away from a $1,000 human genome. Almost every other aspect of our ability to understand biology in information terms is similarly doubling every year.

  

"Our genes are essentially little software programs, and they evolved when conditions were very different than they are today. Take, for example, the fat insulin receptor gene, which essentially says 'hold on to every calorie because the next hunting season may not work out so well.' That gene made a lot of sense tens of thousands of years ago, at a time when food was almost always in short supply and there were no refrigerators. In those days, famines were common and starvation was a real possibility, so it was a good idea to store as many as possible of the calories you could find in your body's fat cells.

"Today, the fat insulin receptor gene underlies an epidemic of weight prob­lems, with two of three American adults now overweight and one in three obese. What would happen if we suddenly turned off this gene in the fat cells? Scientists actually performed this experiment on mice at the Joslin Diabetes Center. The animals whose fat insulin receptor gene was turned off ate as much as they wanted yet remained slim. And it wasn't an unhealthy slimness. They didn't get diabetes or heart disease, and they lived and remained healthy about 20 percent longer than the control mice, which still had their fat insulin receptor gene working. The experimental mice experienced the health benefits of caloric restriction - the only laboratory-proven method of life extension - while doing just the opposite and eating as much as they wanted. Several pharmaceutical companies are now rushing to bring these concepts to the human market."  

About those home genetic testing kits

A genetic testing product includes a "spit kit."

They're here, and here to stay apparently, but they're not the be all and end all. An article at IndyStar.com explains.

Looking into one's genome can be serious business, and experts say people would be better off doing so under the guidance of a genetic counselor.

The tests look not at genes per se, but at changes that show up across the genome in people with certain conditions, said Stephanie Cohen, a genetic counselor with St. Vincent Cancer Genetics Risk Assessment Program. A group of people with these changes may be more likely to display that characteristic, but an individual will not necessarily do so.

Results can be nebulous. For instance, some test for a common mutation that causes cystic fibrosis, Quaid said. More than 1,000 other mutations can also cause this potentially fatal disease. So this result might provide a false sense of security.

The accuracy of such tests has also been called into question. The U.S. Government Accountability Office did an investigation, sending the same individual's sample to three different companies. Each company reported different results.

Nor do the tests take into account non-genetic features of the person being tested, said Elizabeth Kearney, president of the National Society of Genetic Counselors.That's why genetic counselors advocate that people seek advice from them rather than a test tube. In many instances, genetic counselors do not even run tests but glean risk by taking a detailed family history.

Do it yourself? Protect yourself.

Is genetic testing in your future?

Nature magazine asked more than 90 genomics centres and labs to estimate the number of human genome sequences they have in the works. Although far from comprehensive, the tally indicates that at least 2,700 human genomes will have been completed by the end of this month, and that the total will rise to more than 30,000 by the end of 2011.

What does this mean for you and me?

FuturePundit writes: This is an example of why I keep saying that the floodgates on genetic data are opening, that the rate of discovery of what genetic mutations mean is rapidly accelerating, and that we will soon learn enormous amounts about what many thousands of our genetic variants mean. The utility of getting yourself genetically tested is going to rise sharply.

He points to this article:

A handful of physicians have quietly begun using whole-genome sequencing in attempts to diagnose patients whose conditions defy other available tools.

"If one hospital is doing it, you can be sure others will start, because patients will vote with their feet," Elizabeth Worthey, a genomics specialist at the Human and Molecular Genetics Center (HMGC) of the Medical College of Wisconsin in Milwaukee.

Some in the field say we need better regulation of genetic testing. More here. So be wary, but expect this new field to grow.

PIck a number, any number

Ever notice that many pill prescriptions last seven days? Why?

Daniel Gilbert, a professor of psychology at Harvard, writes that certain numbers have magical properties.

The magic numbers are the familiar ones that have something to do with the way we keep track of time (7, say, and 24) or something to do with the way we count (namely, on 10 fingers). The “time numbers” and the “10 numbers” hold remarkable sway over our lives. We think in these numbers (if you ask people to produce a random number between one and a hundred, their guesses will cluster around the handful that end in zero or five) and we talk in these numbers (we say we will be there in five or 10 minutes, not six or 11).

Important decisions are made on the basis of magic numbers.

A recent study of antibiotic treatment published in a leading medical journal began by noting that “the usual treatment recommendation of 7 to 10 days for uncomplicated pneumonia is not based on scientific evidence” and went on to show that an abbreviated course of three days was every bit as effective as the usual course of eight. My doctor had recommended seven. Where in the world had seven come from?

Italy! Seven is a magic number because only it can make a week, and it was given this particular power in 321 A.D. by the Roman emperor Constantine, who officially reduced the week from eight days to seven. The problem isn’t that Constantine’s week was arbitrary — units of time are often arbitrary, which is why the Soviets adopted the five-day week before they adopted the six-day week, and the French adopted the 10-day week before they adopted the 60-day vacation.

So if you're told to take three pills a day for seven days, that's 21. But what if your body really only needs 20?

If even one of those pills is unnecessary — that is, if people who take 20 pills get just as healthy just as fast as people who take 21 — then millions of people are taking at least 5 percent more medication than they actually need. This overdose contributes not only to the punishing costs of health care, but also to the evolution of the antibiotic-resistant strains of “superbugs” that may someday decimate our species. All of which seems like a rather high price to pay for fealty to ancient Rome. 

Might be fun to annoy your doctor with this information next time you're in to get some pills.

A breakthrough in cancer treatment

Advances in genetic technologies have allowed scientists to study the genetic mutations that underlie cancer in much greater detail. The result has been a new approach to drug design. Unlike chemotherapy, which can affect both healthy and cancerous cells and often triggers serious side effects, genetically targeted drugs act selectively on cancer cells that carry the mutation.

Now comes news of an experimental drug designed to block the effects of a genetic mutation often found in patients with malignant melanoma, a deadly cancer with few existing treatments, Technology Review reports.

The drug significantly shrank tumors in about 80 percent of those who carried the mutation. The findings signal a major success for so-called targeted cancer therapies, which are designed to block the effects of genetic mutations that drive the growth of cancer cells.

"This study is a major breakthrough in cancer treatment, and for metastatic melanoma," says Matthew Meyerson, an oncologist and researcher at the Dana Farber Cancer Institute in Boston. "It's a spectacular example of how genome-targeted therapies are beginning to help cancer patients."

In this study, 37 of 48 patients with the mutation responded to the new experimental drug, with their tumors shrinking by more than 30 percent. Tumors completely disappeared in three of those patients. About 30 percent of patients who took the drug the longest developed a specific type of squamous cell carcinoma, a tumor that usually doesn't spread and typically resolves on its own. 

Image: A PET scan of one melanoma patient shows a significant decrease in the size and number of tumors (shown in black) 15 days after treatment with an experimental drug.