Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stomach bacterium damages human DNA

06.09.2011
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 of Zurich have now identified a mechanism of Helicobacter pylori that damages the DNA of cells in the gastric mucosa and sets them up for malignant transformation.

Gastric cancer is one of the most common and often fatal cancers: Every third cancer death is due to gastric carcinoma. The main risk factor for the development of gastric cancer is the chronic infection of the gastric mucosa with the bacterium Helicobacter pylori. Since this bacterium was discovered in 1983, scientists have been puzzling over the molecular mechanisms triggering carcinogenesis. Now, several research teams headed by Prof. Anne Müller and Prof. Massimo Lopes from the Institute of Molecular Cancer Research at the University of Zurich have demonstrated how Helicobacter pylori harms human and animal host cells in in vitro experiments. The study published in the science journal PNAS shows that infection of host cells leads to breaks in both strands of the DNA double helix.

Degree of damage depends on duration of infection

Müller, Lopes and their teams also show that the frequency of the double-strand breaks depends on the intensity and duration of the infection. The DNA breaks induced by H. pylori trigger the cell’s natural DNA damage signaling and repair mechanisms. If the bacterium is killed off with antibiotics within a few hours of infection, most of the breaks can be repaired successfully. Prolonged infections that imitate the conditions in the chronically infected host, however, exhaust the cell’s repair response and the dangerous double-strand breaks can no longer - or only imprecisely - be repaired, causing genetic mutations or the death of the cell. The new findings are in agreement with the previously described genomic instability of gastric cancer cells and will be important for a better understanding of the pathological mechanisms promoting gastric carcinogenesis.

The research was also funded with contributions from the Swiss National Science Foundation, the Schweizer Krebsliga (Swiss Cancer Society) and the Research Credit of the University of Zurich.

Further reading:

Isabella M. Toller, Kai Neelsen, Martin Steger, Mara L. Hartung, Michael O. Hottiger, Manuel Stucki, Behnam Kalali, Markus Gerhard, Alessandro A. Sartori, Massimo Lopes and Anne Müller: The Carcinogenic Bacterial Pathogen Helicobacter pylori Triggers DNA Double-Strand Breaks and a DNA Damage Response in its Host Cells", IN: PNAS Early Edition, doi: 10.1073/pnas.1100959108

Contacts:
Prof. Anne Müller
University of Zurich
Institute of Molecular Cancer Research
Tel. +41 44 635 34 74
Email: mueller@imcr.uzh.ch
Prof. Dr. Massimo Lopes
University of Zurich
Institute of Molecular Cancer Research
Tel. +41 44 635 34 67
Email: lopes@imcr.uzh.ch

Beat Müller | Universität Zürich
Further information:
http://www.uzh.ch

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>