About My Health Careers Internship MedBlogs Contact us

How Does Helicobacter Pylori Bacteria Cause Stomach Cancer?

by Rishika Gupta on November 14, 2017 at 10:47 AM
Font : A-A+

  • 750,000 patients die of stomach cancer each year after developing the disease. The main cause of this cancer is thought to be Helicobacter pylori (H. pylori) bacteria
  • Gastric cancer is one of the five most fatal types of cancer
  • This bacteria has been known destroy the stomach's protective layer, it secretes a protease enzyme called HtrA to penetrate these layers

How Does Helicobacter Pylori Bacteria Cause Stomach Cancer?

Helicobacter pylori, which cause gastric cancer, secretes an enzyme, called HtrA, to penetrate stomach's protective layer found a study published in Cell Host & Microbe journal.

Gastric cancer, also known as stomach cancer is one of the five most fatal types of cancer. According to the World Health Organization (WHO), around 750,000 patients die annually of this disease.


At present, there are no effective therapies for gastric cancer and growing spread of antibiotic resistance is further complicating treatment of the infection. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now identified two mechanisms through which this bacterium can cause gastric cancer. Their findings could result in the development of new therapeutic approaches.

The international team of scientists headed by Dr. Nicole Tegtmeyer of the Chair of Microbiology at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) investigated how bacteria destroy the stomach's protective layer. This protective layer is composed of densely packed epithelial cells that protect the stomach against the effects of gastric acid.

The researchers have now discovered that H. pylori secrete an enzyme, a protease called HtrA, which it uses much like a weapon to penetrate this protective layer. HtrA cleaves the three proteins occludin, claudin-8, and E-cadherin, rupturing the layer of epithelial cells.

As a result, the H. pylori bacteria can access deeper, normally pathogen-free tissue layers, and inflict further damage. This is the first step towards gastric cancer starting to develop.

This first phase, however, is followed by one that is even more dangerous, as the team discovered.

Needle-like protrusions, termed type IV secretion systems, are activated and function as 'molecular syringes.' Using a receptor-dependent mechanism, these inject a bacterial toxin, the CagA protein, through the basolateral membrane of the host cells. The injected CagA subsequently reprograms host cells, making them potentially cancerous.

Another effect of this protein is that it prevents the human immune system from recognizing and eliminating the bacteria - a crucial mechanism for the long-term survival of H. pylori in the human stomach.

Dr. Tegtmeyer expects these findings will make it possible to develop important new antibacterial therapeutic approaches, as HtrA and CagA are ideal novel drug targets. The team has already started to test specific HtrA inhibitors. "We hope that suitable active agents can either completely prevent infection or inhibit the injection of CagA," explains Tegtmeyer.

  1. Nicole Tegtmeyer, Silja Wessler, Vittorio Necchi, Manfred Rohde, Aileen Harrer, Tilman T. Rau, Carmen Isabell Asche, Manja Boehm, Holger Loessner, Ceu Figueiredo, Michael Naumann, Ralf Palmisano, Enrico Solcia, Vittorio Ricci, Steffen Backert11,'Correspondence information about the author Steffen Backert. Helicobacter pylori Employs a Unique Basolateral Type IV Secretion Mechanism for CagA Delivery, Cell host and microbe(2017)DOI:http://dx.doi.org/10.1016/j.chom.2017.09.005

Source: Eurekalert

News A-Z
News Category
What's New on Medindia
Top 7 Benefits of Good Oral Hygiene
Healthy and Safer Thanksgiving 2021
Long-Term Glycemic Control - A Better Measure of COVID-19 Severity
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Shigellosis MRSA - The Super Bug Acid Peptic Disease Food Safety for Health Antibiotics COX - 2 Inhibitors 

Recommended Reading
Gastric Cancer
Stomach (gastric) cancer develops from the stomach lining. It is the third most common cause for ......
Test Your Knowledge on Gastric Cancer
cabbages and potatoes reduce the risk of gastric cancer. Studies such as these aid in controlling .....
Stomach Cancer | Gastric Cancer - Video
Medindia provides informative interesting health videos for all major type of disease; tap here to ....
Infographics on Stomach Cancer
Stomach cancer or gastric cancer is diagnosed late, stomach cancer infographic combines information ...
Acid Peptic Disease
Acid peptic diseases are a collective disorder affecting millions of people worldwide. A general des...
Antibiotics are among the most used and abused medications. This article explains some general featu...
COX - 2 Inhibitors
What are COX–2 Inhibitors? Why are they safer compared to NSAIDs and which conditions are best trea...
MRSA - The Super Bug
MRSA infection is the most dreaded hospital or community acquired infection that can become ......
Shigellosis or Bacillary Dysentery is a common cause of gastro-enteritis worldwide and can cause blo...

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2021

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use