Breast-feeding may significantly cut a woman’s risk of breast cancer if she has an immediate relative that has ever had the disease, according to a study published in the journal Archives of Internal Medicine.
Among women with close family members who have had breast cancer, the risk of developing the disease before menopause sank by 59 percent if she ever breast-fed, according to the research, which used data from more than 60,000 subjects of the Harvard Nurses’ Health Study. The risk of breast cancer in women without the disease in the family was unaffected by breast-feeding. The findings suggest that breast-feeding may prove just as effective a strategy for high-risk women as the use of Tamoxifen, a drug that interferes with estrogen activity and is often used in high-risk women to reduce breast cancer risk [The New York Times]. For women with a high risk of breast cancer, due to factors like a family history of the disease or a genetic predisposition to develop it, the only preventive measures currently used are Tamoxifen and the prophylactic removal of the breasts.
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An international health agency has officially ruled that tanning beds pose as likely to cause cancer as cigarettes, asbestos, and arsenic. The International Agency for Research on Cancer (IARC) moved ultraviolet-emitting tanning beds from the category of “probably carcinogenic” to definitely “carcinogenic to humans.”
The IARC is an expert committee that makes recommendations to the World Health Organization. It made its decision following a review of research which concluded that the risk of melanoma – the most deadly form of skin cancer – was increased by 75% in people who started using sunbeds regularly before the age of 30. In addition, several studies have linked sunbed use to a raised risk of melanoma of the eye [BBC News]. The study results and the new classification were published in the journal Lancet Oncology, and experts say the findings are likely to prompt calls for stricter regulations of tanning salons.
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Chemotherapy destroys cancer cells, but it also kills healthy cells. In addition, cancer cells left behind after treatment can develop resistance to therapy, rendering follow-up treatment ineffective. But a new type of cancer treatment that uses cellular “Trojan horses” to slip into cancer cells could remedy that. In a study published in Nature Biotechnology, Australian researchers describe a method that has successfully treated aggressive and resistant tumors in mice and dogs.
The technique uses a rising technology known as RNA interference, or RNAi, which was the subject of research for the 2006 Nobel Prize in medicine recipients. This technology prevents the cell from manufacturing proteins by muting the genes responsible for their production, and relies on “mini-cells” to silence these genes. In the new study, these mini-cells were produced by bacteria and then coated with antibodies the cancer cells recognized, which allowed the mini-cells to target and slip inside of cancer cells like a Trojan horse.
The researchers use a two-step attack against the cancer cells. The first wave of mini-cells releases molecules that switch off the production of proteins that make the cancer cell resistant to chemotherapy. A second wave of EDV [mini] cells is then accepted by the cancer cell and releases chemotherapy drugs, killing the cancer cell. “The beauty is that our EDVs operate like ‘Trojan Horses’ They arrive at the gates of the affected cells and are always allowed in” [Reuters], says study coauthor Jennifer MacDiarmid.
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Apple chief executive and all-around tech visionary Steve Jobs reportedly received a liver transplant two months ago in Tennessee, and is on track to return to work by the end of the month. Jobs presumably underwent the procedure to treat a reappearance of the cancer he was diagnosed with several years ago. In 2004 Jobs had surgery to remove a rare, slow-growing type of pancreatic cancer, called a islet cell neuroendocrine tumor, but he was thought to be in remission until last year, when a period of drastic weight loss last year led to frenzied speculation that the cancer had returned [The Guardian].
Jobs’s health has been a matter of intense interest to Apple investors, who feel that his leadership is key to the company’s continuing success, and questions have been raised about the company’s handling of the matter. In January, the notoriously secretive Jobs made a rare public statement attributing his weight loss to a “hormone imbalance”. Just a few days later, however, he was forced to admit that the situation was “more complex” than first thought, before announcing his intention to step down from day to day activities at Apple for six months [The Guardian].
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Scientists have taken another step in cellular reprogramming that points the way towards the use of a patient’s own cells to treat genetic diseases. In a proof of concept study, researchers took skin cells from patients with a rare condition, Fanconi anemia, which causes skeletal problems and bone-marrow failure, and raises sufferers’ risk of cancer [Technology Review]. In the skin cells, the researchers fixed the genetic defects that caused the disease, and then reprogrammed the cells to act like stem cells capable of growing into any type of tissue.
The corrected stem cells could be grown into blood precursor cells for therapy. As these would carry a patient’s own DNA, except for the mutation responsible for the illness, they could be transplanted without risk of rejection by the body’s immune system [Times Online]. However, the patched up cells were not used to treat patients in this study, because it isn’t yet clear whether such cells are safe. Comments molecular geneticist Chris Mathew: “In future it may become possible to transfer the corrected stem cells back into the patient, but much work remains to be done before this can be transferred from the lab bench to the bedside” [The Scientist].
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What if we stopped trying to cure cancer, and learned how to live with it? That’s the provocative question asked by mathematical oncologist Robert Gatenby in an essay published in Nature (subscription required). Gatenby argues that by trying to eradicate tumors with heavy doses of chemotherapy, doctors sometimes end up selecting for drug-resistant cancer cells that can spread rapidly once treatment is halted. Instead, he suggests giving patients moderate doses that aim to stabilize the tumor and prevent its growth.
If doctors were guided by this principle, it would change treatment fundamentally, Gatenby says. “Your whole goal is to keep the tumor stable…. With a mouse ovarian cancer model, if you treat it with a very high dose, the tumor goes away. It looks like you’ve cured it. But a couple weeks later it comes back and starts killing animals. This is a standard outcome. What we did is use smaller doses of drugs and applied them when necessary. We were able to keep tumors stable and mice alive indefinitely” [Wired], he says.
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Tumors may physically trigger depression by producing chemicals that induce negative mood swings, according to a new study. The research, conducted in rats, allowed for the isolation of “just the physiological effects of the tumors from the psychological effects…. The tumors themselves are sufficient to induce depression” [The Scientist], says lead researcher Leah Pyter.
The new study, published in the Proceedings of the National Academy of Sciences, showed first that rats who had cancer exhibited several behavioral symptoms associated with depression. The researchers gave a forced swimming test to 100 rats, some healthy and some with cancer, and found that the sick rats did not try as hard to escape—a behavior similar to that seen in humans with depression. The sick rats were also less interested in sugar water, which is the the clear preference for healthy rats.
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A major new lawsuit is challenging the notion that human genes can be patented just like the latest mousetrap built by a basement inventor. The case focuses on two genes, BRCA1 and BRCA2, that are linked to a higher risk of breast and ovarian cancer, and which were patented by the company Myriad Genetics more than 10 years ago. Now, the ACLU has organized a lawsuit backed by organizations representing more than 100,000 doctors and geneticists, and will argue that the information contained in each person’s DNA should not be private property.
The plantiffs also include individual cancer patients like Genae Girard, who was diagnosed with breast cancer, and took Myriad’s genetic test to see if her genes also put her at increased risk for ovarian cancer, which might require the removal of her ovaries. The test came back positive, so she wanted a second opinion from another test. But there can be no second opinion [The New York Times]. Since Myriad owns the patent to both the two genes and the test that looks for them, no other company can develop a competing test.
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The beating of the heart inside an embryo doesn’t just circulate blood through the developing creature, it also triggers the formation of blood stem cells, the cells that give rise to all other forms of blood cells, according to two new studies. The surprising findings show that the physical force of the heartbeat and blood flowing through the aorta cause embryonic stem cells to differentiate–although researchers don’t yet understand quite how this is accomplished.
The findings could eventually have practical applications for people with blood cancers and other diseases that are treated with transplants of bone marrow, the site of blood stem cell production. Scientists can make red and white blood cells easily in the laboratory, but bone marrow patients need blood stem cells to constantly replenish their blood supply. Producing these cells, also called hematopoietic stem cells, is much more difficult…. Only about a third of patients who require bone marrow transplants have matching donors. “Basically we cannot offer optimal therapy to two-thirds of patients” [Science News], says Leonard Zon, coauthor of one of the new studies. If researchers can learn how the body stimulates blood stem cell production, they may be able to duplicate the process in the lab, says Zon.
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In recent years, antioxidants have been touted as a secret to healthy living: The molecules bind to reactive oxygen compounds called “free radicals” that are known to damage the body’s tissues. The amount of oxidative damage increases with age, and according to one theory of aging it is a major cause of the body’s decline [The New York Times]. But a new study examined the effects of the antioxidant vitamins C and E when combined with an exercise regimen, and found a considerably more complicated story. The researchers found that free radicals may be beneficial in small doses, and may even help protect against diabetes. And mopping them up with antioxidants may do more harm than good [BBC News].
During a workout, the muscles metabolize glucose to create energy, but in the process some free radicals are released. The body has a natural defense mechanism to combat these free radicals, but many researchers had theorized that the body can’t catch all of the harmful compounds, which makes antioxidant supplements sound like a logical solution.
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Cardiologist and author John Sotos has a theory about why Abraham Lincoln was so tall, why he appeared to have lumps on his lips and even why he had gastrointestinal problems. The 16th president, he contends, had a rare genetic disorder — one that would likely have left him dead of cancer within a year had he not been assassinated [Time]. But for Sotos to prove his case, he needs a snip from a historical relic: a piece of the bloodstained pillowcase on which the dying Lincoln rested his head after he was shot at Ford’s Theater on April 14, 1865.
The piece of cloth is displayed under glass at the Grand Army of the Republic Civil War Museum and Library in Philadelphia. Sotos has asked the museum’s board for a sample of the pillowcase, which is stained with both blood and brain matter. But the board is fiercely debating whether to concede to his request. “This is the Shroud of Turin of Civil War history,” said Andy Waskie, a board member…. “We are guardians in trusteeship of this extraordinarily important artifact. On the basis of pure science, the testing is of interest. We have not eliminated it as an option . . . but we want more information” [The Philadelphia Inquirer].
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In a small step forward in the scientific effort to save the Tasmanian devil from the infectious disease that threatens the species with extinction, researchers have developed the first blood test for the ailment known as devil facial tumour disease (DFTD). Previously it has not been possible to determine whether a Tasmanian devil had DFTD until symptoms, such as facial lesions, appeared. However by early detection the diseased animals could be separated (and possibly culled) from healthy animals in the wild [Times Online]. The captive populations that are being kept as insurance against possible extinction could also be tested routinely.
Says researcher Robert Shellie: “We think it is quite a significant breakthrough. In a nutshell, what we have done is develop a blood test for DFTD. It’s a simple test and requires … only a drop of blood from an ear-prick. To be able to determine whether the disease is there, before you can see tumours on the faces of the devils, means that we can detect the disease at a much earlier stage” [The Australian].
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U.S. Attorney General Eric Holder announced yesterday that the federal government will not prosecute all sales of medical marijuana, marking another stark change in policy from the days of the Bush administration, which conducted frequent raids under a zero tolerance policy.
Medical marijuana distributors were targeted by federal officials under Bush even in states that had passed laws allowing use of the drug for medical purposes by cancer patients, those dealing with chronic pain or other serious ailments. Holder said the priority of the new administration is to go after egregious offenders operating in violation of both federal and state law, such as those being used as fronts for drug dealers [Los Angeles Times]. Under the new policy, medical marijuana dispensaries that abide by state laws will be left alone.
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A double-whammy method of screening for ovarian cancer, which is sometimes called the silent killer, seems to catch many cases in the early stages when the disease is more curable, researchers say. A massive study tested the impact of two types of screening: One is a blood test which measures the levels of a protein called CA125, which is often higher in women with ovarian cancer. The other is an ultrasound scan that looks for abnormalities in the ovaries [The Guardian]. When used in conjunction, the two tests showed great promise in catching cancer cases early on.
Ovarian cancer is one of the most lethal types of cancer. About 21,000 U.S. women are diagnosed each year and more than 15,000 die. The high death rate is due to the fact that the disease is often detected at a late stage of development, when chances for a cure are much lower [Los Angeles Times].
However, many of the women in the study had false positive results, especially those who received only an ultrasound test, leading some to unnecessarily have their ovaries removed. Lead researcher Ian Jacobs cautioned that “women thinking of having [an ultrasound screening] must understand and realize that there’s a possibility it will do more harm than good. We have reason to think it will save lives,” he added, “and then the question is, will it save enough lives to balance out the harm it does?”[The New York Times].
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A simple urine test is being developed that would revolutionize the treatment of prostate cancer by differentiating between the benign and aggressive forms of the disease.
While prostate cancer is one of the most commonly diagnosed cancers in men, the real challenge for treatment tends to lie in measuring the progress of the disease. A person can live a long time with benign prostate cancer, but the aggressive kind of tumor grows much more quickly and requires urgent treatment. The current method for distinguishing between the two can involve several rounds of testing, including an invasive and painful biopsy.
The urine test, which will not be ready for at least another three to five years, would be an easy and inexpensive way to determine which type of cancer is present, researchers report in Nature [subscription required]. Research for the test began when doctors found that men with an aggressive form of prostate cancer carry elevated levels of a particular molecule in their urine [The Guardian].
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