October 30, 2006, 7:03 PM CT
Negative Brca Test Doesn't Guarantee Safety
In women with a strong family history of breast cancer a negative BRCA test does not necessarily guarantee safety from breast cancer. These women are still at increased risk of developing the disease according to findings from the latest research. These women should start breast cancer screening at earlier age from 35 to 40 years.
Scientists explain that defects in the BRCA genes account for only around 5% of all diagnosed breast cancers in developed countries.
In this study published of the 277 women, 190 had breast cancer, 48 had ovary cancer, and 33 had both. Six were free of the disease.
Among the 531 living female relatives who were tested for the genetic faults, almost half (49%) tested negative. Of these, 28 developed breast cancer and four developed ovary cancer.
Among the 184 first-degree relatives testing negative, 4 different BRCA1 and 2 "phenocopies" were identified, accounting for around one in four test results.
A phenocopy is when a patient develops the condition that a particular gene predisposes them to, but they test negative for the inherited genetic fault. This is likely to be due to other genetic variants (modifier genes) that mimic the physiological changes produced by that specific gene fault.........
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October 17, 2006, 9:55 PM CT
Femara More Effective Than Nolvadex
Scientists affiliated with the BIG-98 trial comparing Femara® (letrozole) to Nolvadex® (tamoxifen) have reported that longer follow-up confirms the superiority of Femara in postmenopausal women with early, hormone-positive breast cancer. The details of this follow-up study were presented at the 2006 annual European Society for Medical Oncology (ESMO) meeting in Istanbul in October.
Femara is an aromatase agent that is approved for first-line therapy of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced breast cancer; metastatic breast cancer; advanced breast cancer in postmenopausal women with disease progression following anti-estrogen treatment; and as neo-adjuvant treatment. It is also approved for extended adjuvant treatment in early breast cancer, following 5 years of therapy with Nolvadex, based on phase III clinical trial results. Several clinical trials are ongoing to help elucidate optimal timing and/or sequencing of aromatase agents and Nolvadex in the therapy of hormone-positive women with breast cancer in the adjuvant setting, and it appears that aromatase agents are providing superior results to those of Nolvadex in several settings in the therapy of hormone-positive breast cancer.........
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October 17, 2006, 4:48 AM CT
Studying Tumor Genomics
The newly established Berkeley Cancer Genome Center, led by members of the Life Sciences Division in the Department of Energy's Lawrence Berkeley National Laboratory, is one of seven Cancer Genome Characterization Centers to receive awards from the National Cancer Institute and the National Human Genome Research Institute. Earlier today the two institutes, both part of the National Institutes of Health, announced a three-year, $35 million project which will seek to identify important genetic changes involved in lung, brain, and ovarian cancers through genome analysis.
The Berkeley Cancer Genome Center is a collaboration between Berkeley Lab, the University of California at Berkeley, and the University of California at San Francisco. The center's director is Joe W. Gray, who is the director of the Life Sciences Division and Berkeley Lab's Associate Laboratory Director for Life and Environmental Sciences. Computational biologist Paul Spellman of the Life Sciences Division is codirector.
"The Berkeley Cancer Genome Center will be focused on identifying changes to the populations of messenger RNA that occur in cancer," says Spellman. Such changes are indicative of different kinds of proteins produced by the altered genomes of tumor cells.
Spellman says, "The Center will use the Affymetric Exon 1.0 array platform to measure exon-specific expression" - exons are the coding sequences in a gene - "of at least 1,000 samples per year, and will use computational tools to identify those whose behavior suggests they might play a role in cancer".........
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September 25, 2006, 9:52 PM CT
Insights into Breast Cancer Genetics
Last few decades stands out in the history of breast cancer, with significant progress in elucidating the genetics and molecular basis of breast cancer. Majority of researchers believe in a "two hit hypothesis" as initiating events of breast cancer in patients who stand a high risk of developing breast cancer because of inherited genetic abnormalities. This double hit theory assumes that even though people are born with a specific a genetic abnormality that would predispose them to higher risk of breast cancer, additional genetic mutations induced by the environment may be actually required to cause the process of breast cancer formation.
During the early part of 1990s, scientists have discovered mutations in the p53 gene which is present on the 17th chromosome to be responsible for causing Li-Fraumeni syndrome. The mutation in Li-Fraumeni syndrome is associated with increased breast cancer risk, sarcomas and various other types of tumors including brain tumors. In the year 1997, mutations in the PTEN gene, on chromosome 10 have been linked to Cowden's syndrome. Presence of Cowden's syndrome is associated with higher risk of breast cancer, and lesions in the skin. Cowden's syndrome may be associated with elevated risk of breast cancer, and lesions on the skin. Recent research has demonstrated that mutation in the STK11/LKB1 gene, which is located on the 19th chromosome, is associated with Peutz-Jeghers syndrome. Peutz-Jeghers syndrome has been associated with gastrointestinal malignancies, breast cancers and hamrtomas. Gene mutations in MLH1 and MLH2 are associated with Muir-Torre syndrome, which has been shown to be associated with increased risk of genitourinary system tumors, gastrointestinal system abnormalities and breast cancer.........
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September 20, 2006, 9:59 PM CT
Sea Squirts Problem Persisting
Scientists have just completed a field survey of the invasive sea squirt colony on the Georges Bank, first discovered in 2003. A wider area was searched for the sea squirt this year, and it was mapped over about twice the area observed in 2004. Results show that the species is present in two adjacent areas totaling 88 square miles in U.S. waters near the U.S.-Canada boundary. The very large mat-like colonies observed in 2004 have been replaced by fewer smaller ones. The Georges Bank occurrence is the largest known infestation of colonial sea squirts in a major offshore fishing ground.
For the fourth consecutive year, federal and university researchers have surveyed two areas on Georges Bank where an invasive colonial sea squirt continues to thrive on the gravel bottom. The colonies are denser than in 2005 over the 88 square-mile area observed. But scientists found no colonies in nearby Canadian waters, indicating they have not spread eastward. The Georges Bank squirts are a species of the genus Didemnum.
"The area of seabed covered by the colonies has doubled at 75 percent of the sites we observed in both 2005 and 2006," said Dr. Page Valentine of the U.S. Geological Survey, who tracks occurrences of the species off the northeastern U.S., and elsewhere in the world. Greater density of colonies observed during the survey is evidence that the infestation is persistent, and not a short-lived phenomenon.........
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September 20, 2006, 8:52 PM CT
Can a spoonful of sugar treat cancer?
A leading Yorkshire scientist is trying to develop new drugs by synthesising different forms of the special sugars found in cancer cells. Now, with support from the Association for International Cancer Research (AICR), Dr Robert Falconer will be using his discovery to search for new molecules to stop disease spread.
Dr Falconer, a Lecturer in Medicinal Chemistry based in the Institute of Cancer Therapeutics at the University of Bradford explains: "On the surface of cancer cells there is a long molecule, called polysialic acid, which is made up of about 200 identical simple sugars associated withgether.
"Polysialic acid has been found on the surface of many different human cancers. When these cancer cells start to spread, they appear to get more polysialic acid on their surface. We think that this helps these cells 'unstick' from their neighbouring cells, so they can start invading the surrounding tissues and moving away from the original tumour.........
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September 9, 2006, 8:57 AM CT
Breaking Down The Barriers
Dione Farria, M.D. (left), studies patient radiological images with resident Jennifer Demertzis, M.D
Although breast cancer is more common among white women, African-American women are far more likely to die of the disease.
What accounts for this fundamental racial imbalance? Dione Farria, M.D., knows all too well: African-American women are less likely to get mammograms that can detect breast cancer early when it is more easily treated.
Socioeconomic influences such as limited access to health care, mistrust of the health-care system and the lack of health insurance, both for screening and treatment, play a major role in this disparity.
For Farria, the inequity in breast cancer deaths has been a personal call to action. A radiologist who specializes in breast imaging, she is one of the rare few in the field who also holds a master's degree in public health. Her work to improve the quality of health care for people in less privileged segments of society helps Farria understand the barriers to cancer screening in a way that most radiologists don't.
"Mammography screening for breast cancer is a huge public health issue," says Farria, assistant professor of radiology. "In parts of St. Louis City and North St. Louis County, we see twice as much advanced breast cancer than would be expected.
"Many of these women are not aware of their breast cancer risk or are fearful of getting a mammogram. Those are precisely the women we are trying to reach".........
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August 20, 2006, 3:03 PM CT
Regional Storage Facilities Could Handle Nuclear Waste
The Bush administration is eagerly pushing nuclear power as a way to help solve the U.S. energy crisis. But in its new plan for nuclear waste management, the administration is taking the wrong approach, says an MIT professor who studies the nuclear energy industry.
"My hope is that over time, the administration will rethink its priorities in this area," says Richard Lester, professor of nuclear engineering and director of the Industrial Performance Center.
In a recent article published in Issues in Science and Technology, Lester argued that the Bush administration's plan, known as GNEP (Global Nuclear Energy Partnership), is not the best way to encourage further development of nuclear energy.
GNEP, which President Bush announced earlier this year, is meant to stimulate the nuclear industry by coming up with better ways to manage spent nuclear fuel. The plan focuses on reprocessing spent fuel, but Lester believes the administration should focus on finding regional storage facilities for the nuclear waste.
Right now, uncertainty over how to deal with spent fuel, which remains radioactive for hundreds of thousands of years, is one of the major obstacles to the construction of new plants. Thousands of spent fuel rods are now stored in secure pools or concrete casks located near nuclear plants, which is not considered a long-term solution.........
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August 13, 2006, 9:30 AM CT
RNA-Based Drug Kills Prostate Cancer Cells
Acting as a genetic Trojan horse, an experimental RNA-based drug -- the first of its kind -- tricks its way into prostate cancer cells and then springs into action to destroy them, while leaving normal cells unharmed.
The drug, developed at Duke University Medical Center, uses one type of genetic material, called targeting RNA, to enter cancer cells, and another type, called silencing RNA, to stop the expression of a protein that keeps the cells alive.
In tests in mice with prostate cancer, the drug shrank the size of their tumors by half, while the tumors in control mice that did not receive the drug continued to grow, said co-author of study Bruce Sullenger, Ph.D., director of Duke's Translational Research Institute and chief of the Division of Experimental Surgery.
The mice showed no side effects from the therapy, Sullenger said.
"This study represents the first step in creating an RNA-based drug for cancer," said lead author James McNamara, Ph.D. a postdoctoral fellow in experimental surgery. "It provides a 'proof of principle' that an entirely RNA-based drug can work with minimal side effects, and it shows it is possible to overcome a number of of the obstacles that have hampered the development of RNA-based drugs."
The study is published in the August 2006 issue of Nature Biotechnology, which is now available online. The research was funded by the National Institutes of Health.........
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August 13, 2006, 9:09 AM CT
Success Of MRI-guided Breast Biopsy
Now radiologists are coming to the help of surgeons and pathology. They can use X-ray to confirm that MRI-guided breast biopsy has successfully removed the lesion.
"Contrast-enhanced MRI of the breast is becoming increasingly useful in patients with lesions that cannot be detected with other techniques," says Basak Erguvan-Dogan, MD, radiologist in Breast Imaging at the University of Texas M.D. Anderson Cancer Center in Houston. "However, it is hard to confirm removal of the targeted lesion because the abnormality does not enhance after being removed from the breast," she said.
Currently, patients who have MRI-guided needle localization and excision of abnormalities may be asked to have follow-up breast MRI; if the lesion has not been successfully removed, another biopsy procedure will need to be done. "By taking x-rays of the lesion specimen, then slicing it up and taking additional x-rays, we can determine if the lesion has been removed or if additional tissue needs to be excised while the patient is still in the operating room," Dr. Erguvan-Dogan said.
Whole specimen and sliced specimen radiography waccording toformed in 10 patients, and X-raying the lesion as a whole and in slices proved to be valuable, said Dr. Erguvan-Dogan. "In all five cancerous cases, sliced specimen radiographs showed the lesion in question, helped the pathologist correctly identify the lesion while the patient was still in the operating room and helped the surgeon obtain negative surgical margins," said Dr. Erguvan-Dogan. In addition, "whole specimen radiography is able to correctly locate fractured biopsy needle localization wires, which may be removed before the patient left the operating room," she said.........
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