 |
|
Improved DNA stool test could detect digestive cancers in multiple organs
June 02, 2009ROCHESTER, Minn. -- Mayo Clinic researchers have demonstrated that a noninvasive screening test can detect not only colorectal cancer but also the common cancers above the colon -- including pancreas, stomach, biliary and esophageal cancers. This is one of more than 100 Mayo Clinic studies being presented at Digestive Disease Week 2009 in Chicago, May 30 - June 4.
Gastrointestinal (GI) cancers account for approximately one in four cancer deaths. While high cure rates can be achieved with early-stage detection for each type, only colorectal cancer is currently screened at the population level. Most people associate colorectal cancer screening with invasive colonoscopy, but previous Mayo Clinic research has shown that stool DNA testing can identify both early-stage colorectal cancer and precancerous polyps. Researchers are now studying the use of noninvasive stool DNA testing to detect lesions and cancer throughout the GI tract.
"Patients are often worried about invasive tests like colonoscopies, and yet these tests have been the key to early cancer detection and prevention," says David Ahlquist, M.D., Mayo Clinic gastroenterologist and lead researcher on the study. "Our research team continues to look for more patient-friendly tests with expanded value, and this new study reveals an opportunity for multi-organ digestive cancer screening with a single noninvasive test."
The researchers studied 70 patients with cancers throughout the digestive tract. Besides colon cancer, the study looked at throat, esophagus, stomach, pancreatic, bile duct, gallbladder and small bowel cancers to determine if gene mutations could be detected in stool samples. Using a stool test approach developed at Mayo Clinic, researchers targeted DNA from cells that are shed continuously from the surface of these cancers. Also studied were 70 healthy patients. Stool tests were performed on cancer patients and healthy controls by technicians unaware of sample source. The stool DNA test was positive in nearly 70 percent of digestive cancers but remained negative for all healthy controls, thus demonstrating the approach's feasibility.
Stool DNA testing detected cancers at each organ site, including 65 percent of esophageal cancers, 62 percent of pancreatic cancers, and 75 percent of bile duct and gallbladder cancers. In this series, 100 percent of both stomach and colorectal cancers were detected. Importantly, stool test results did not differ by cancer stage; early-stage cancers were just as likely to be detected as late-stage cancers.
"It's very exciting to see this level of sensitivity for digestive cancer detection in our first look at this test application," says Dr. Ahlquist, "Historically, we've approached cancer screening one organ at a time. Stool DNA testing could shift the strategy of cancer screening to multi-organ, whole-patient testing and could also open the door to early detection of cancers above the colon which are currently not screened. The potential impact of this evolution could be enormous."
In October 2008, this Mayo Clinic research team published results of a multicenter study using first-generation stool DNA testing. In the seven-year, multicenter study (Ann Intern Med 2008;149:441-50), researchers found that the first-generation stool DNA tests were better than fecal blood tests for detecting cancer and precancerous polyps of the colon. In January 2009 (Gastroenterology 2009;136:459-70), Mayo researchers published some technical improvements that nearly doubled the sensitivity of stool DNA testing for detecting premalignant polyps and increased cancer detection to about 90 percent, which is the approximate rate of detection observed for CT colonography.
Researchers hope that the next generation tests will have significant improvements in accuracy, processing speed, ease of patient use and affordability. "We anticipate that next generation tests will also be able to predict the tumor site, which will help physicians direct diagnostic studies and minimize unnecessary procedures," says Dr. Ahlquist.
Mayo Clinic
The researchers studied 70 patients with cancers throughout the digestive tract. Besides colon cancer, the study looked at throat, esophagus, stomach, pancreatic, bile duct, gallbladder and small bowel cancers to determine if gene mutations could be detected in stool samples. Using a stool test approach developed at Mayo Clinic, researchers targeted DNA from cells that are shed continuously from the surface of these cancers. Also studied were 70 healthy patients. Stool tests were performed on cancer patients and healthy controls by technicians unaware of sample source. The stool DNA test was positive in nearly 70 percent of digestive cancers but remained negative for all healthy controls, thus demonstrating the approach's feasibility.
Stool DNA testing detected cancers at each organ site, including 65 percent of esophageal cancers, 62 percent of pancreatic cancers, and 75 percent of bile duct and gallbladder cancers. In this series, 100 percent of both stomach and colorectal cancers were detected. Importantly, stool test results did not differ by cancer stage; early-stage cancers were just as likely to be detected as late-stage cancers.
"It's very exciting to see this level of sensitivity for digestive cancer detection in our first look at this test application," says Dr. Ahlquist, "Historically, we've approached cancer screening one organ at a time. Stool DNA testing could shift the strategy of cancer screening to multi-organ, whole-patient testing and could also open the door to early detection of cancers above the colon which are currently not screened. The potential impact of this evolution could be enormous."
In October 2008, this Mayo Clinic research team published results of a multicenter study using first-generation stool DNA testing. In the seven-year, multicenter study (Ann Intern Med 2008;149:441-50), researchers found that the first-generation stool DNA tests were better than fecal blood tests for detecting cancer and precancerous polyps of the colon. In January 2009 (Gastroenterology 2009;136:459-70), Mayo researchers published some technical improvements that nearly doubled the sensitivity of stool DNA testing for detecting premalignant polyps and increased cancer detection to about 90 percent, which is the approximate rate of detection observed for CT colonography.
Researchers hope that the next generation tests will have significant improvements in accuracy, processing speed, ease of patient use and affordability. "We anticipate that next generation tests will also be able to predict the tumor site, which will help physicians direct diagnostic studies and minimize unnecessary procedures," says Dr. Ahlquist.
Mayo Clinic
DNA Current Events and DNA News RSSScientists at UA, collaborating institutions decode maize genome
Scientists from the University of Arizona led by Arizona Genomics Institute director Rod A. Wing and from collaborating institutions have deciphered the complete genetic code of the maize plant for the first time.
Ancestry attracts, but love is blind
People preferentially marry those with similar ancestry, but their decisions are not necessarily based on hair, eye or skin colour.
Scientists unlock clues for tailoring corn plant for food, energy needs
Scientists have long known that the offspring of two inbred strains tend to be superior to both their parents. Now, a team of researchers including a University of Florida geneticist has discovered clues to why that might be the case for one of the most important crops in the world: corn.
Cigarettes Harbor Many Bacteria Harmful to Human Health
Cigarettes are "widely contaminated" with bacteria, including some known to cause disease in people, concludes a new international study conducted by a University of Maryland environmental health researcher and microbial ecologists at the Ecole Centrale de Lyon in France.
Technique finds gene regulatory sites without knowledge of regulators
A new statistical technique developed by researchers at the University of Illinois allows scientists to scan a genome for specific gene-regulatory regions without requiring prior knowledge of the relevant transcription factors.
Unknowlingly consuming endangered tuna
While most of us would never willingly consume a highly endangered species, doing so might be as easy as plucking sushi from a bento box.
New research into the mechanisms of gene regulation
A team led by Penn State's Ross Hardison, T. Ming Chu Professor of Biochemistry and Molecular Biology, has taken a large step toward unraveling how regulatory proteins control the production of gene products during development and growth.
New Maize Map to Aid Plant Breeding Efforts
In a massive survey of genetic diversity in maize, also known as corn, researchers across the United States, have developed a gene map that should pave the way to significant improvements in a plant that is a major source of food, fuel, animal feed and fiber around the world.
UAB Researchers Discover Antibody Receptor Identity, Propose Renaming Immune-System Gene
Researchers at the University of Alabama at Birmingham (UAB) have uncovered the genetic identity of a cellular receptor for the immune system's first-response antibody, a discovery that sheds new light on infection control and immune disorders.
GEN reports on enhancing the applications of qPCR
Quantitative polymerase chain reaction (qPCR) technology is experiencing a surge of interest and rapid expansion as a result of advances such as instrumentation that pushes capacity to 1,536 wells and optimization-free multiplexing.
More DNA Current Events and DNA News Articles
 |
DNA: The Secret of Life by James D. Watson (Author) James Watson, the co-discoverer of the structure of DNA and author of the international bestseller "The Double Helix" tells the story of the amazing molecule since its discovery fifty years ago, following modern genetics from his own Nobel prize-winning work in the fifties to today's Dolly the sheep, designer babies and GM foods. Professor Watson introduces the science of modern genetics, along with its history and its implications, in this magnificent guide to one of the most triumphant achievements of human science. |
 |
Thames & Kosmos Genetics and DNA by Thames & Kosmos In depth investigation of genetics and DNA. Isolate the DNA from a tomato, learn about inheritance and how traits are expressed, build a DNA model, breed bacteria to experiment with genetic engineering. The full-color, 48-page manual guides your experiments. |
 |
DNA Science: A First Course, Second Edition by David Micklos (Author), Greg A. Freyer (Author) This is the second edition of a highly successful textbook (over 50,000 copies sold) in which a highly illustrated, narrative text is combined with easy–to–use thoroughly reliable laboratory protocols. It contains a fully up–to–date collection of 12 rigorously tested and reliable lab experiments in molecular biology, developed at the internationally renowned Dolan DNA Learning Center of Cold Spring Harbor Laboratory, which culminate in the construction and cloning of a recombinant DNA molecule. Proven through more than 10 years’ of teaching at research and nonresearch colleges and universities, junior colleges, community colleges, and advanced biology programs in high school, this book has been successfully integrated into introductory biology, general biology,... |
 |
Science Wiz DNA Kit by Sciencewiz The central concepts of molecular biology becomes child's play in this set of camp favorites. 40 Page science book and materials with 8 Major Activities. Makes the DNA revolution accessible. Extract DNA from a fruit Probe and spool real DNA Build a double helix Solve a chromosome puzzle Is it a boy or a girl? Play the gene construction game Country of Origin: U.S.A., China & Hong Kong. |
 |
Genes and DNA (Kingfisher Knowledge) by Richard Walker (Author), Steve Jones (Author) Genes & DNA explores modern genetics, from an investigation of genes and their function, to forensics, therapy, and cloning. |
 |
K'NEX Educational DNA, Replications and Transcription Set by K'NEX K'Nex kits inspire young minds and satisfy kids' curiosity on how to build simple creations. Each innovative kit keeps young builders busy and intrigued for hours on end. This K'Nex Kit allows one to two kids to work as a team. Models demonstrate the structure and processes of DNA and mRNA molecules. Everything comes in a large compartmentalized storage case with snap-on lid. Curriculum sold separately. |
 |
DNA Starring: Tom Conti Also With: Samantha Bond (Performer) Forensics expert Joe Donovan uses science to snare killers—and save himself. Award-winning actor Tom Conti (Shirley Valentine; Reuben, Reuben) stars as Joe Donovan, an accomplished but troubled criminologist who returns from a mental breakdown to lead Manchester’s crack Forensic Investigations Unit. Called in to consult on a murder case that suspiciously resembles the one that drove him into near madness years ago, Donovan redeems his reputation and rediscovers his devotion to the job. Yet his professional dedication bleeds into his personal life, alienating his wife (Samantha Bond, Die Another Day, Tomorrow Never Dies) but appealing to his son (Ryan Cartwright, The Grimleys), who wants to follow in his father’s footsteps. Packed with fascinating procedural details and... |
 |
The Stuff of Life: A Graphic Guide to Genetics and DNA by Mark Schultz (Author), Zander Cannon (Illustrator), Kevin Cannon (Illustrator) The Stuff of Life gives readers a complete introduction to the history of genetics that's as easy to understand as it is entertaining to read. |
 |
DNA on DNA by DNA Previously released on CD by No More Records, now issued on a limited edition 2LP featuring newly-discovered songs exclusive to this LP: "Pompeii," "Shrinking Thing," "Drinking Water," plus two encores from DNA's final performance at CBGB's. Definitive collection of studio and live recordings by New York's seminal no wave band DNA. Surviving two line-ups over a brief period of four years; this highly influential, strikingly original and extremely under-recorded band left a huge void in its wake. Formed in 1978, Brazilian-raised singer/guitarist Arto Lindsay hastily assembled an international trio of non-musicians. Robin Crutchfield played keyboard and Japan's Ikue Mori played drums. DNA played their first gig within weeks and recorded their first 7" shortly afterwards. The ear of Brian... |
 |
Signature in the Cell: DNA and the Evidence for Intelligent Design by Stephen C. Meyer (Author) One hundred fifty years ago, Charles Darwin revolutionized biology, but did he refute intelligent design (ID)? In Signature in the Cell, Stephen Meyer argues that he did not. Much confusion surrounds the theory of intelligent design. Frequently misrepresented by the media, politicians, and local school boards, intelligent design can be defended on purely scientific grounds in accordance with the same rigorous methods that apply to every proposed origin-of-life theory. Signature in the Cell is the first book to make a comprehensive case for intelligent design based upon DNA. Meyer embarks on an odyssey of discovery as he investigates current evolutionary theories and the evidence that ultimately led him to affirm intelligent design. Clearly defining what ID is and is... |
| © 2009 BrightSurf.com |