Going from ulcers to cancer

August 22, 2008

Researchers have uncovered a big clue as to why some of the bacteria that cause stomach ulcers pose a greater risk for serious problems like stomach cancer than others; it turns out these bacteria can exploit the surrounding stomach cells to protect them from the immune system.

Helicobacter pylori is a bacterial strain that can infect the human stomach and induce inflammation, ulcers, and potentially even stomach cancer. However, only a small fraction of H. pylori infections ultimately lead to cancer, leading researchers to figure out what biological events will trigger this path.

One type of H. pylori strain that seems to increase disease risk is the cag+ strain, which contains a set of proteins that allows it to inject bacterial proteins into cells following attachment to the stomach lining; this interaction between bacteria and gastric cells may be a key contributor to chronic damage.

Richard Peek and colleagues investigated a cag+ strain in mouse models of H. pylori infection and found that a protein called CagE could induce gastric cells to turn on a receptor called Decay-accelerating factor (DAF); DAF acts to remove nearby immune proteins that can kill cells to prevent unwanted immune damage.

In essence, the bacteria use the DAF receptor on the host cell they're attached to like a bodyguard to protect them from the immune system. Peek and colleagues also note that by continually inducing DAF expression, H. pylori creates an environment of persistent inflammation that can reduce the threshold required for more serious diseases to develop.

Source: American Society for Biochemistry and Molecular Biology

Explore further: Are stem cells the link between bacteria and cancer?

Related Stories

Are stem cells the link between bacteria and cancer?

August 17, 2017
Gastric carcinoma is one of the most common causes of cancer-related deaths, primarily because most patients present at an advanced stage of the disease. The main cause of this cancer is the bacterium Helicobacter pylori, ...

Ulcer-causing bacteria tamed by defect in cell-targeting ability

November 21, 2011
Without the ability to swim to their targets in the stomach, ulcer-causing bacteria do not cause the inflammation of the stomach lining that leads to ulcers and stomach cancer, according to a new study by researchers at the ...

Other stomach microbiota modulate resistance to H. pylori-driven ulcers

March 25, 2013
Mice with different naturally occurring stomach bacteria have distinct susceptibilities to disease caused by Helicobacter pylori, the well-known cause of ulcers in humans, according to a study published online ahead of print ...

Ulcer-causing bacteria induces stomach stem cell growth in mice, researchers find

May 6, 2015
The ulcer-causing bacterium Helicobacter pylori can directly interact with stomach stem cells, causing the cells to divide more rapidly, according to a new study by researchers at the Stanford University School of Medicine.

AIDS patients face risk for esophageal, stomach cancers

September 24, 2012
People with AIDS are at increased risk for developing esophageal and stomach carcinoma as well as non-Hodgkin lymphomas (NHLs), according to a new study in Gastroenterology, the official journal of the American Gastroenterological ...

Stomach bacterium damages human DNA

September 6, 2011
The stomach bacterium Helicobacter pylori is one of the biggest risk factors for the development of gastric cancer, the third most common cause of cancer-related deaths in the world. Molecular biologists from the University ...

Recommended for you

Expert: Be concerned about how apps collect, share health data

October 20, 2017
As of 2016 there were more than 165,000 health and wellness apps available though the Apple App Store alone. According to Rice University medical media expert Kirsten Ostherr, the Food and Drug Administration (FDA) regulates ...

Three million Americans carry loaded handguns daily, study finds

October 19, 2017
An estimated 3 million adult American handgun owners carry a firearm loaded and on their person on a daily basis, and 9 million do so on a monthly basis, new research indicates. The vast majority cited protection as their ...

More teens than ever aren't getting enough sleep

October 19, 2017
If you're a young person who can't seem to get enough sleep, you're not alone: A new study led by San Diego State University Professor of Psychology Jean Twenge finds that adolescents today are sleeping fewer hours per night ...

Across Asia, liver cancer is linked to herbal remedies: study

October 18, 2017
Researchers have uncovered widespread evidence of a link between traditional Chinese herbal remedies and liver cancer across Asia, a study said Wednesday.

Eating better throughout adult years improves physical fitness in old age, suggests study

October 18, 2017
People who have a healthier diet throughout their adult lives are more likely to be stronger and fitter in older age than those who don't, according to a new study led by the University of Southampton.

Global calcium consumption appears low, especially in Asia

October 18, 2017
Daily calcium intake among adults appears to vary quite widely around the world in distinct regional patterns, according to a new systematic review of research data ahead of World Osteoporosis Day on Friday, Oct. 20.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.