(Press-News.org) ROCHESTER, Minn. -- Researchers at Mayo Clinic have shown that it is possible to detect endometrial cancer using tumor DNA picked up by ordinary tampons. The new approach specifically examines DNA samples from vaginal secretions for the presence of chemical "off" switches -- known as methylation -- that can disable genes that normally keep cancer in check.
The finding is a critical step toward a convenient and effective screening test for endometrial cancer, which is the most common gynecologic malignancy in the United States. The results are published in the journal Gynecologic Oncology.
"Unfortunately, there is no equivalent to a Pap smear or a mammogram for endometrial cancer," says Jamie Bakkum-Gamez, M.D., a gynecologic oncologist at Mayo Clinic and lead author of the study. "We know that the earlier a woman is diagnosed, the better the likelihood is that she is going to have a positive outcome from cancer treatment. Our goal is to use our findings to develop a tool for the early detection of endometrial cancer that women could use in the comfort of their own homes."
The American Cancer Society estimates that over 50,000 new cases of endometrial cancer will be diagnosed in 2015. Though the malignancy is more common in white women, blacks are usually diagnosed at a later stage and are more likely to die from the disease. In most cases, women discover they have endometrial cancer only after abnormal vaginal bleeding prompts a visit to the doctor. However, more insidious molecular changes take place long before such symptoms appear.
Before a cell can turn cancerous, it has to subvert the genetic checks and balances that normally keep it from growing out of control. Thousands of different genes likely play a role in suppressing the development of tumors. In cancer, these tumor suppressor genes are often mutated outright or simply masked with chemical tags or methyl groups known as methylation. Previous research has shown that a wide variety of genes are turned "off" by such methylation in different types of cancer, leading many investigators to explore how these molecular markers could be used to diagnose or even treat the disease.
A small study published in 2004 showed that DNA samples collected from tampons was excessively methylated or hyper-methylated in women with endometrial cancer compared to women without the disease. However, in the years since then little progress has been made in turning the approach into a practical screening test.
"No one really took that idea and ran with it," says Dr. Bakkum-Gamez. "We wanted to take this initial study one step further, and use advances in technology to see if we could develop a better method of differentiating between cancerous and benign cells."
First, Dr. Bakkum-Gamez and her colleagues obtained samples from 66 women who were about to undergo a hysterectomy, 38 because of endometrial cancer and 28 due to other indications. Each woman used an intravaginal tampon to collect vaginal secretions and also underwent endometrial brushing, a procedure that uses a wire brush to scrape cells from the inner lining of the uterus.
The researchers isolated DNA from the samples and then analyzed 97 methylation sites along 12 different genes, half initially discovered by members of the research team and half previously reported by other researchers. They found that methylation was higher in specimens from women with endometrial cancer for 9 of the 12 genes analyzed. The results were similar regardless of whether DNA was acquired through a tampon or endometrial brushing.
Despite the encouraging results, the researchers say they need to further refine their method before it can be used clinically. Now, Dr. Bakkum-Gamez and her colleagues are looking for additional genes that are mutated or methylated in the earliest stages of endometrial cancer. Once they have the final lineup of genes to use in the test, they plan to validate the test using samples obtained through a clinical trial that is currently accruing 1,000 women at higher risk of endometrial cancer.
The final product may look very similar to Cologuard, an at-home screening kit recently approved by the FDA. Cologuard was co-developed by Mayo Clinic and Exact Sciences, and analyzes DNA from stool samples for alterations associated with colon cancer.
"Cologuard could revolutionize colon cancer screening, and our test has the potential to do the same for endometrial cancer," says Dr. Bakkum-Gamez. "At the heart of this approach is a desire to make cancer screening patient-centered, by using a product that is already widely accepted and readily available, even in resource-poor settings."
Co-authors of the paper include: Matthew Maurer, Kieran Hawthorne, Jesse Voss, Trynda Kroneman, Abimbola Famuyide, M.B.B.S., Amy Clayton, M.D., Kevin Halling, M.D., Ph.D., Sarah Kerr, M.D., William Cliby, M.D., Sean Dowdy, M.D., Benjamin Kipp, Ph.D., Andrea Mariani, M.D., Ann Oberg, Ph.D., Karl Podratz, M.D., Ph.D., and Viji Shridhar, Ph.D., all of Mayo Clinic
The study was funded by the Mayo Clinic Specialized Program of Research Excellence (SPORE) in Ovarian Cancer from the National Institutes of Health, the Office of Women's Health Research Building Interdisciplinary Careers in Women's Health (BIRCWH), Mayo Clinic's NCI Cancer Center Support Grant, and the Intramural Research Program of the National Cancer Institute.
About Mayo Clinic Cancer Center
As a leading institution funded by the National Cancer Institute, Mayo Clinic Cancer Center conducts basic, clinical and population science research, translating discoveries into improved methods for prevention, diagnosis, prognosis and therapy. For information on cancer clinical trials, call 1-855-776-0015 (toll-free).
About Mayo Clinic
Mayo Clinic is a nonprofit organization committed to medical research and education, and providing expert, whole-person care to everyone who needs healing. For more information, visit http://mayocl.in/1ohJTMS, orhttp://newsnetwork.mayoclinic.org/.
At any given moment, our sun emits a range of light waves far more expansive than what our eyes alone can see: from visible light to extreme ultraviolet to soft and hard X-rays. Different wavelengths can have different effects at Earth and, what's more, when observed and analyzed correctly, those wavelengths can provide scientists with information about events on the sun. In 2012 and 2013, a detector was launched on a sounding rocket for a 15 minute trip to look at a range of sunlight previously not well-observed: soft X-rays.
Each wavelength of light from the sun inherently ...
Using data from orbiting observatories, including NASA's Spitzer Space Telescope, and ground-based facilities, an international team of astronomers has discovered an outburst from a star thought to be in the earliest phase of its development. The eruption, scientists say, reveals a sudden accumulation of gas and dust by an exceptionally young protostar known as HOPS 383.
Stars form within collapsing fragments of cold gas clouds. As the cloud contracts under its own gravity, its central region becomes denser and hotter. By the end of this process, the collapsing fragment ...
Over the last 30 years, short sight, or myopia, has become a global health problem. The most dramatic rise has been in Singapore, Taiwan, China's cities and elsewhere in East Asia. Rates can be as high as 80-90 per cent among children leaving secondary schools in the region. As many as a fifth of them have severe myopia and so are at high risk of eye problems in later life. In Western countries rates are increasing; although not as rapidly as in East Asia.
The Myopia Mystery
The cause of myopia, and the means to prevent it, are unclear despite more than 150 years of ...
Bethesda, MD (March 24, 2015) -- A new guideline from the American Gastroenterological Association (AGA) changes clinical practice by recommending longer surveillance periods for patients with asymptomatic pancreatic cysts and new criteria that limits surgery to those who will receive the most benefit.
It is estimated that more than 15 percent of patients who visit a doctor's office or hospital outpatient department will receive an MRI or other type of scan,2 and of those, about 15 percent will have incidental pancreatic cysts. Once detected, these cysts trigger anxiety ...
Washington, DC (March 24, 2015) - As congenital heart disease (CHD) treatment advances, children with these conditions are living into adulthood, and over time, they may need additional treatment. A new expert consensus paper released today by the Society for Cardiovascular Angiography and Interventions (SCAI), American Association for Thoracic Surgery (AATS), American College of Cardiology (ACC), and The Society of Thoracic Surgeons (STS) provides guidance on transcatheter pulmonic valve replacement, or tPVR, for children and adults who were previously treated for CHD.
DETROIT - Major League Baseball pitchers who underwent a second Tommy John surgery saw their performance decline and their career shortened, according to researchers at Henry Ford Hospital.
In a retrospective, case-controlled study, researchers analyzed performance and longevity data of 33 pitchers who had a second surgery following the original elbow reconstruction between 1996 and 2012 and compared them with pitchers of similar age who had no prior Tommy John surgery. Key findings for pitchers after a second surgery:
65 percent returned to pitching at MLB level.
This news release is available in French. Socio-economic inequalities between First Nations communities, and also between these communities and the non-Aboriginal population of Canada, determine the nature, the intensity and the direction of First Nations migration flows. Pursuing educational careers, finding work, and seeking better health and living conditions are the main reasons for First Nations migration. These are the findings of research by Marilyn Amorevieta-Gentil, Robert Bourbeau and Norbert Robitaille, of the University of Montreal, which were presented ...
DURHAM, N.C. -- For people infected with the human papilloma virus (HPV), the likelihood of clearing the infection and avoiding HPV-related cancer may depend less on the body's disease-fighting arsenal than has been generally assumed.
A new study finds that the body's ability to defeat the virus may be largely due to unpredictable division patterns in HPV-infected stem cells, rather than the strength of the person's immune response.
If the mathematical model behind the findings holds up, it could point to ways of tweaking the way infected cells divide in order to make ...
It's no surprise that some of the most celebrated leaders in the business world also happen to be self-promoting narcissists.
New research from Brigham Young University's Marriott School of Management finds those strong characteristics are not such a bad thing--as long as those leaders temper their narcissism with a little humility now and then.
"Just by practicing and displaying elements of humility, one can help disarm, counterbalance, or buffer the more toxic aspects of narcissism," said Bradley Owens, assistant professor of business ethics at BYU. "The outcome ...
Great leaders are often good communicators. In the process of communication, the relationship between leaders and their followers develops spontaneously according to new research from the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig and the State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research in Beijing. When a member becomes the group leader, the leader's brain activity in the left temporo-parietal junction, known as representing others' mental states, begins to synchronize with that in the ...