THURSDAY, July 29 (HealthDay News) — The genetic makeup of
breast cancer tumors may be a better predictor of how well a woman will
fare than a tumor’s size and appearance, which has been the traditional
way of looking at cancers, new research suggests.
A European team of researchers analyzed the genetic makeup of 595
breast cancer tumors and compared the results to non-cancerous breast
tissue. They then used algorithms to separate the tumors into eight types
based on changes in the structure of the chromosomes, including deletions
or amplifications of DNA, the study authors said.
In doing so, researchers showed that certain alterations in the
patterns of DNA were able to predict cancer prognosis and response to
particular treatments.
These findings join a host of recent scientific discoveries that
suggest that the key to thwarting breast cancer may lie in the tumor’s
DNA.
“Is this going to go into clinical practice tomorrow? No,” said Dr.
Daniel Silver, assistant professor of medicine at the Dana-Farber Cancer
Institute in Boston. “This is just one step of many toward a deeper
understanding of breast cancer.”
The study was published in a recent issue of Science Translational
Medicine.
Over the past few years, oncologists have increasingly relied on
analyses of the DNA of breast cancer cells to determine which cancers are
most likely to respond to certain treatments and which have the greatest
chances of recurrence, clarified Dr. Stephen Sener, past president of the
American Cancer Society and a chief of the division of surgical oncology
at the University of Southern California’s Keck School of Medicine.
“For many years, until about the turn of this century, breast cancer
was thought to be one basic disease,” Sener said. “But since the human
genome was elucidated, now people are working on the breast cancer genome.
We’re learning a lot more about how cancers develop and how they
behave.”
Instead of size, grade, number of lymph nodes impacted and other
anatomical features of the tumor itself, many oncologists now peer at the
genetic makeup of the tumor. Already, lab testing can show if cancer cells
are estrogen receptor (ER) positive, meaning the cells use estrogen to
promote their growth; progesterone receptor (PR) positive; hormone
receptor negative or whether they have too many copies of the HER-2 gene,
which promotes cell proliferation.
For each type, different medications may or may not work. For ER
positive cancers, for example, drugs such as tamoxifen that block hormones
can be effective, but would not work in women with hormone receptor
negative cancers.
“There are some breast cancers that are very large that never spread.
On the other hand, there are some patients who have very small cancers who
have lots of lymph nodes involved,” Sener said. “Why are those patients
different? What a lot us have realized is the standard anatomical
descriptions of breast cancer is inadequate.”
DNA technology has already revolutionized oncologists’ treatment
decisions, Sener said.
“This new way of looking at breast cancer genetic has allowed us to be
much more focused about the prognosis, who will respond to chemo, hormones
or both,” Sener said. “It’s really a major advance in breast cancer
technology that has emerged in the last 3 to 5 years.”
“Eventually, the size of the tumor will probably be an irrelevant piece
of information,” he said.
More information
There’s more on breast cancer at the American Cancer Society.

WASHINGTON (Reuters) – Overweight volunteers who took Orexigen’s experimental drug Contrave, designed to reduce cravings, lost about 13 pounds (6 kg) over a year, U.S. researchers reported on Thursday.

Those who got the drug said they felt less desire for sweet or starchy foods; felt fuller and had fewer cravings, the researchers said.

Their study, published in the Lancet medical journal, also suggested that feared side-effects from the drug were mild and went away over time.

But one expert said more studies are needed before regulators can assume the drug is safe.

Data from the company-sponsored study has already been presented to the U.S. Food and Drug Administration, which has a panel of advisers scheduled to consider approval in December.

The Lancet submitted it for review by experts before publishing it, said Frank Greenway of the Pennington Biomedical Research Center at Louisiana State University, who led the trial.

Contrave is a combination of the antidepressant bupropion, a generic version of GlaxoSmithKline’s Wellbutrin, and naltrexone, used to treat alcoholism and other addictions.

Greenway and colleagues tested two formulations of Contrave against a placebo in 1,700 overweight or obese volunteers.

Only half the volunteers finished the trial, dropping out for various reasons.

“It is something that seems to be characteristic of obesity studies,” Greenway said in a telephone interview.

“The people in the placebo group seemed to drop out more frequently because they were dissatisfied with the lack of weight loss. People in the drug arm seemed to drop out more because of side-effects. Overall, the groups seemed to be equal.”

But of those who finished the trial and also got the highest dose of the drug, mean weight loss was 13 pounds (6 kg) compared to 3 pounds (1.4 kg) for those who got the placebo.

The drug did raise blood pressure slightly at first, a known side-effect of bupropion and a huge worry for a drug being taken by overweight people. But this increase leveled off after a small time, Greenway reported.

“The safety is really nothing different from what we would expect from the components,” Greenway said.

One expert said more study is needed to show if the drug is safe. The drugs have been linked to anxiety, insomnia and to raised blood pressure, as well as to thoughts of suicide.

But the trial showed no increase in any of these, said Arne Astrup of the University of Copenhagen in Denmark.

“These findings suggest that the combination might have fewer adverse psychiatric effects than its components given separately, but a meta-analysis of all continuing or completed phase 3 studies of this combination treatment is needed to assess this effect more accurately,” Astrup wrote in a commentary in the Lancet.

Three U.S. companies are competing to get new weight loss drugs approved by the FDA.

FDA advisers voted against Vivus Inc’s Qnexa earlier this month, expressing concerns that it could cause depression, memory loss and potential birth defects.

Arena Pharmaceuticals Inc has a drug called lorcaserin up for consideration in September.

(Reporting by Maggie Fox; Editing by Tim Dobbyn)

HONG KONG (Reuters) – Researchers have identified three fragments in gluten that appear to trigger a disorder in people who are allergic to the wheat protein.

The findings, published on Thursday in the journal Science Translational Medicine, may lead to a more targeted cure instead of what sufferers practice now — life-long abstinence from food containing gluten, such as cereal, pasta, cookies and beer.

“If you can (narrow down) the toxicity of an allergen to a few components, that enables you to make a highly targeted therapy in a way that you no longer need to target the whole immune system,” said researcher Robert Anderson of The Walter and Eliza Hall Institute of Medical Research in Victoria, Australia.

For people with the allergy, gluten causes an overreaction in the immune system that hurts the lining of the small intestine, leaving it unable to absorb vitamins, minerals and other nutrients from food.

The sufferer is subject to chronic fatigue and risks osteoporosis, infertility, miscarriage and even cancers of the digestive tract — symptoms of what is called celiac disease.

In the study, 244 people with celiac disease in Australia and Britain ate food with gluten over three days and researchers then analyzed the immune cells in their blood samples.

While gluten has some 16,000 components, Anderson said only three were responsible for the allergy.

“To our surprise, the majority of the immune response to gluten can fall back to just three components of gluten. It means the immune response is highly focused on maybe some particular forbidden fragments of the gluten,” he said by telephone.

Anderson and some colleagues had since gone on to design an injectable drug containing very small doses of each of the three components.

The thought is to expose the immune system to regular but very small doses of the offending allergens so that the body can gradually get used to them.

(Reporting by Tan Ee Lyn; Editing by Ken Wills and Ron Popeski)