Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Enzyme, lost in most mammals, is shown to protect against UV-induced skin cancer

26.01.2005


In a finding that broadens our insight into the cause of certain kinds of UV-induced skin cancer, researchers at Erasmus University Medical Center (Rotterdam, The Netherlands) have employed an evolutionarily ancient enzyme-repair system to identify the principal type of DNA damage responsible for the onset of skin-tumor development. The researchers’ findings also suggest that this enzyme system may be useful in developing preventative therapies against skin cancer.



Ultraviolet light is a known source of damage to our DNA, but under normal conditions humans and other mammals are capable of removing UV-induced DNA damage by a DNA repair mechanism called nucleotide excision repair. Insufficient repair of UV-induced DNA damage, which for example may occur after excessive unprotected sunbathing, can lead to cellular death – recognized as sunburn of the skin – and may cause permanent changes in the DNA (mutations) that ultimately can result in the onset of skin cancer. Thus far it was not clear how the two major types of UV-induced DNA lesions – cyclobutane pyrimidine dimers (CPDs) and (6-4)photoproducts (6-4PPs) – contribute to the processes of cell death and cancer formation. Identifying the relative contributions of the two types of damage to tumor formation is critical for the development of therapies that could help prevent skin cancer. Moreover, CPDs and 6-4PPs have particular potential to cause lasting damage to mammalian cells because photolyases – a class of enzymes capable of efficiently repairing these lesions – have apparently been lost from placental mammals over the course of evolution.

Thus, most mammals, including humans, can only repair these lesions through a much less direct and elaborate process called nucleotide excision repair.


In the new work, Dr. Bert van der Horst and colleagues studied the effects of CPD and 6-4PP lesions by providing mice with transgenes encoding CPD and 6-4PP photolyase enzymes.

Although mice do not ordinarily produce these enzymes, which remove either CPD or 6-4PP lesions by using visible light as an energy source, expression of the transgenes allowed rapid photolyase-mediated repair of these lesions. The researchers found that transgenic mice bearing the CPD photolyase transgene, in contrast to mice bearing the 6-4PP photolyase transgene, showed superior resistance to the deleterious effects of UV irradiation. Not only could CPD photolyase transgenic animals withstand doses of UV light that cause severe sunburn in normal mice, but they also showed superior resistance to UV-induced skin cancer. This work clearly points to CPD lesions as the major intermediate in UV-induced cellular damage leading to non-melanoma skin cancer. Importantly, it also suggests that photolyases may be successfully employed as a genetic tool to combat UV-induced skin cancer.

Judith Jans, Wouter Schul, Yurda-Gul Sert, Yvonne Rijksen, Heggert Rebel, Andre P.M. Eker, Satoshi Nakajima, Harry van Steeg, Frank R. de Gruijl, Akira Yasui, Jan H.J. Hoeijmakers, Gijsbertus T.J. van der Horst: "Powerful Skin Cancer Protection by a CPD-Photolyase Transgene"

The other members of the research team include Judith Jans of Erasmus University Medical Center, Rotterdam, presently at University of California, Berkeley; Wouter Schul of Erasmus University Medical Center, Rotterdam and Tohoku University; Yurda-Gul Sert, Yvonne Rijksen, Andre P.M. Eker, Jan H.J. Hoeijmakers, and Gijsbertus T.J. van der Horst of Erasmus University Medical Center, Rotterdam; Heggert Rebel and Frank R. de Gruijl of Leiden University Medical Center; Satoshi Nakajima of Novartis, Institute of Tropical Disease, Singapore; Harry van Steeg of National Institute of Public Health and the Environment in Bilthoven, The Netherlands; and Akira Yasui of Tohoku University. This work was supported by the Dutch Cancer Foundation, the Association for International Cancer Research, and the Japanese Ministry of Education, Science, and Culture.

Heidi Hardman | EurekAlert!
Further information:
http://www.current-biology.com
http://www.cell.com

More articles from Life Sciences:

nachricht Repairing damaged hearts with self-healing heart cells
22.08.2017 | National University Health System

nachricht Biochemical 'fingerprints' reveal diabetes progression
22.08.2017 | Umea University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>