Tuesday, May 24, 2011

Fingerprint of radiation exposure discovered in thyroid cancer | Bioscience Technology Online


Fingerprint of radiation exposure discovered in thyroid cancer

Neuherberg, 24. Mai 2011. Scientists from the Helmholtz Zentrum München have discovered a genetic change in thyroid cancer that points to a previous exposure of the thyroid to ionising radiation. The gene marker, a so-called „radiation fingerprint“ was identified in papilliary thyroid cancer cases from Chernobyl victims, but was absent from the thyroid cancers in patients with no history of radiation exposure. The results are published in the current issue of PNAS.

The research team, led by Prof. Horst Zitzelsberger and Dr. Kristian Unger from the Radiation Cytogenetics Unit of the Helmholtz  Zentrums München, in collaboration with Prof. Geraldine Thomas, Imperial College London, studied thyroid cancers from children exposed to the radioiodine fallout from the Chernobyl nuclear reactor explosion. The team compared the genetic information from these tumours to that found in the same type of tumour that arose in children born more than one year after the explosion, after the radioactive iodine had decayed away. The number of copies of a small fragment of chromosome 7 was found to be increased only in the tumours from the irradiated children, establishing this as one of the first genetic markers that indicate a radiation aetiology of cancer.

This breakthrough is the first time since the reactor accident in 1986 that scientists have been able to discriminate between the cancers caused by the radioactive contamination and those that arise naturally.  Prof. Zitzelsberger ascribes the success of this study to the careful collection, documentation and storage of thyroid cancers from the Chernobyl region in the Chernobyl Tissue Bank. He noted that this unique collection of materials made it possible for the team to compare for the first time tumours from children of the same age and regional background. The availability of the genetic marker, according to Prof. Zitzelsberger, will improve both the clinical diagnosis of thyroid cancer and our understanding of how radioactive iodine causes the disease to develop. In future studies funded by EURATOM in the project „EpiRadBio“ the group will extend the study to determine if the genetic fingerprint is able to indicate the level of radiation exposure that is required to cause the cancer.

Additional Information

Original Publication:

Hess, J. et al Gain of chromosome band 7q11 in papillary thyroid carcinomas of young patients is associated with exposure to low-dose irradiation. Proceeding of the National Academy of Sciences USA (PNAS); Link to publication

Caption:
picture above: Julia Heß, Prof. Dr. Horst Zitzelsberger, Dr. Kristian Unger
picture below: In papillary thyroid carcinomas, more copies of the CLIP2 gene (red) are detected than of a reference gene (green)

About Helmholtz Zentrum München

The Helmholtz Zentrum München is the German Research Centre for Environmental Health. The leading research facility in this field, it conducts research into chronic and complex diseases caused by the interaction of environmental factors and an individual’s genetic disposition. The Helmholtz Zentrum München has about 1,700 staff members and is headquartered in Neuherberg in the north of Munich on a 50-hectare research campus. The Helmholtz Zentrum München is a member of the Helmholtz Association, Germany’s largest scientific organization, a community of 17 scientific-technical and medical-biological research centers with a total of 30,000 staff members. www.helmholtz-muenchen.de

Contacts for media representatives

Sven Winkler, Helmholtz Zentrum München – German Research Centre for Environmental Health (GmbH), Ingolstädter Landstrasse 1 85764 Neuherberg, Germany. Phone.: +49  89-3187-3946 . Fax +49 89-3187-3324, Email: presse@helmholtz-muenchen.de

Scientific contact

Prof. Dr. Horst Zitzelsberger, Abteilung für Strahlenzytogenetik, Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Ingolstädter Landstraße 1 85764 Neuherberg. Phone.: + 49 89-3187-3421 .
Email: zitzelsberger@helmholtz-muenchen.de

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