Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Papillomavirus silences innate immune response

07.12.2009
In the 1980s, Harald zur Hausen and his co-workers discovered that specific types of human papillomavirus (HPV) cause cervical cancer. Scientists soon found out how these pathogens cause cells to degenerate. It is known today that the main culprits are viral proteins E6 and E7. Both proteins switch off different cellular control functions, thus promoting cell growth.

Professor Dr. Frank Rösl and his co-workers at DKFZ have now discovered another mechanism by which the E6 oncoprotein of high-risk HPV16 promotes carcinogenesis. The oncogene silences production of an immune protein called interferon-kappa.

Interferons are proteins which are part of our immune system and are responsible primarily for stimulating the immune response to viruses and tumors. Interferons are produced by white blood cells and other cell types. Interferon-kappa is relevant for HPV infections, because it is produced mainly in cells of the skin and mucosa (keratinocytes) which are the preferred hosts of the viruses. If interferon-kappa is not working in cells, other proteins involved in immune defense also cease to function properly.

Dr. Bladimiro Rincon-Orozco of Rösl's team has now shown for the first time that HPV16 switches off the interferon-kappa gene by biochemical modification of DNA. Such alterations of the genetic material are called epigenetic mutations. Studying HPV infected cells in a culture dish, the research team observed that interferon-kappa is epigenetically silenced. They were later able to confirm this result in cervical cancer tissue samples.

"Interferon-kappa is an important part of what is called innate immunity," Frank Rösl explains. Using this evolutionary old defense mechanism, the body can defend itself immediately after being infected with pathogenic agents, while formation of the specific "acquired" immune system may take some time. "By switching off the interferon production, the viruses prevent infected cells from being destroyed by this type of immune response," says Rösl, explaining the strategy of the virus that causes cancer. In the next step, the researchers are planning to investigate whether administering interferon-kappa can slow down the growth of cervical cancer cells and may thus support treatment of the disease.

Legend: Electron micrograph of human papilloma viruses

Credit: Hanswalter Zentgraf, German Cancer Research Center

Bladimiro Rincon-Orozco, Gordana Halec, Simone Rosenberger, Dorothea Muschik, Ingo Nindl, Anastasia Bachmann, Tina Maria Ritter, Bolormaa Dondog, Regina Ly, Franz X. Bosch, Rainer Zawatzky und Frank Rösl: Epigenetic Silencing of Interferon-κ in Human Papillomavirus Type 16–Positive Cells. Cancer Res 2009; 69: (22) November 15, 2009

The German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ) is the largest biomedical research institute in Germany and is a member of the Helmholtz Association of National Research Centers. More than 2,000 staff members, including 850 scientists, are investigating the mechanisms of cancer and are working to identify cancer risk factors. They provide the foundations for developing novel approaches in the prevention, diagnosis, and treatment of cancer. In addition, the staff of the Cancer Information Service (KID) offers information about the widespread disease of cancer for patients, their families, and the general public. The Center is funded by the German Federal Ministry of Education and Research (90%) and the State of Baden-Württemberg (10%).

Dr. Sibylle Kohlstädt | EurekAlert!
Further information:
http://www.dkfz.de
http://www.dkfz.de/de/presse/pressemitteilungen/2009/images/HPV_1.jpg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>