More than 50 percent of the world's population is infected with Helicobacter, which causes chronic inflammation of the stomach lining and is strongly linked to the development of gastric ulcers and stomach cancer. Stomach cancer is the second leading cause of cancer-related deaths worldwide.
Helicobacter infection results in increased expression of gastrin, although its role in cancer development has been unclear. High levels of gastrin lead to the development of stomach cancer, but absence of gastrin has been shown to increase the numbers of tumors in the gastric antrum, the lower section of the stomach that empties into the small intestine.
To reconcile this apparent incongruity, a group led by Dr. Wang studied Helicobacter infection and stomach cancer in animal models with either high expression of gastrin or no gastrin at all. They found that Helicobacter infection in mice with high levels of gastrin resulted in cancer of the gastric corpus (main body of the stomach), whereas infection in gastrin-deficient mice developed cancer in the gastric antrum.
The latest research by Dr. Wang and his colleagues appears in the July 2009 issue of The American Journal of Pathology.
Dr. Wang, with CUMC's Dr. Shigeo Takaishi, and their colleagues, argue that gastrin may serve as a "rheostat" for the stomach. Gastrin likely plays a central role in the safety network for the protection from mucosal damage caused by gastric acid secretion induced by gastrin itself, and thus either too much or too little gastrin could predispose a person to stomach cancer. Therefore, clinicians in the future may need to be more careful about prescribing acid-suppressive drugs for long-term use in patients infected with Helicobacter, Dr. Wang says.
In future studies, Dr. Wang and colleagues plan to study "host factors other than gastrin that are also important for Helicobacter-associated gastric carcinogenesis." These include specific cytokines and chemokines induced by Helicobacter infection and modulated by gastrin, that link inflammation and cancer. In addition, they plan to study the role of other non-Helicobacter bacteria that colonize the stomach when acid secretion is suppressed, since bacterial overgrowth likely contributes to gastric carcinogenesis.
The work was supported by grants from the National Institutes of Health, the Medical Research Council, the Welcome Trust and the Wolfson Foundation.
Columbia University Medical Center provides international leadership in basic, pre-clinical and clinical research, in medical and health sciences education, and in patient care. The medical center trains future leaders and includes the dedicated work of many physicians, scientists, public health professionals, dentists, and nurses at the College of Physicians & Surgeons, the Mailman School of Public Health, the College of Dental Medicine, the School of Nursing, the biomedical departments of the Graduate School of Arts and Sciences, and allied research centers and institutions. Established in 1767, Columbia's College of Physicians & Surgeons was the first institution in the country to grant the M.D. degree. Among the most selective medical schools in the country, the school is home to the largest medical research enterprise in New York State and one of the largest in the country. For more information, visit www.cumc.columbia.edu.
The American Journal of Pathology is the official journal of the American Society for Investigative Pathology. It seeks to publish high-quality, original papers on the cellular and molecular biology of disease. The editors accept manuscripts that advance basic and translational knowledge of the pathogenesis, classification, diagnosis, and mechanisms of disease, without preference for a specific analytic method. High priority is given to studies on human disease and relevant experimental models using cellular, molecular, animal, biological, chemical, and immunological approaches in conjunction with morphology.
Alex Lyda | EurekAlert!
Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine
NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Physics and Astronomy
21.11.2017 | Life Sciences