Navigation Links
Repairing DNA damage: Researchers discover critical process in cancer treatment
Date:11/6/2008

Montreal, November 6, 2008 From the sun's UVA rays to tobacco smoke, our environment is chock-full of DNA-damaging agents that can lead to cancer. Thanks to our body's DNA repair mechanisms, however, the effects of many carcinogens can be reversed thereby preventing the formation of tumours.

Now, according to a new study published in the early online edition of Proceedings of the National Academy of Sciences of the USA (PNAS), scientists from the Universit de Montral and the Maisonneuve-Rosemont Hospital Research Centre have identified a new biochemical pathway which controls DNA repair.

"Our study is the first to identify a regulatory role for the ATR protein in a specific DNA repair system, which is called nucleotide excision repair or NER," says Elliot Drobetsky, senior author and associate professor of immunology and oncology at the Universit de Montral.

"NER is a critical DNA repair system that removes pieces of damaged DNA before these pieces can be converted into genetic mutations that destroy the function of tumour-preventing proteins in the body. Characterizing how the NER system is turned on or off is critical to understanding how tumours develop. In this system, ATR is the key that turns on the repair machinery."

ATR-mediated NER often defective in tumour cells

The scientific team used cultured lung cells to investigate the role of ATR in NER function. They found that inhibiting ATR resulted in a dysfunctional NER system and, during a very critical period of the cell's growth cycle, damaged DNA was not repaired at all.

What's more, they discovered that some tumour cell lines are completely deficient in ATR-mediated NER, which provides solid evidence that the DNA repair function of ATR may be pivotal in cancer development. "Our study reveals an original mechanism to explain how exposure to environmental carcinogens initiate and promote cancer," adds Dr. Drobetsky.

Chemotherapy implications

The goal of conventional chemotherapy is to kill tumour cells leaving normal cells relatively unaffected by damaging their DNA. As such, in what may seem paradoxical, many chemotherapeutic drugs which are used to cure cancer are themselves powerful carcinogens that can also cause cancer.

"As shown in the current study, a non-functional ATR pathway resulting in limited DNA repair may be characteristic of many tumour cell types, but not of normal noncancerous cells. Determining if the NER system is working in patient tumours may therefore be an important first step to chemotherapy prescribing practices," says Yannick Auclair, the study's lead author and a PhD student at the Universit de Montral.

Any tumours identified as defective in ATR-mediated repair are expected to respond extremely well to chemotherapy, because the cells in these tumours would be extremely hypersensitive to certain anti-cancer drugs unlike normal cells in the rest of the body.

"These findings open a whole new area of research," says Dr. Drobetsky. "Our data harbour critical implications not only for understanding how cancer develops but also for devising new strategies to greatly improve cancer treatment."


'/>"/>

Contact: Sylvain-Jacques Desjardins
sylvain-jacques.desjardins@umontreal.ca
514-343-7593
University of Montreal
Source:Eurekalert

Related biology news :

1. Corn researchers discover novel gene shut-off mechanisms
2. Researchers at UH explore patient preferences for personalized medicine
3. UC Davis researchers discover a key to aggressive breast cancer
4. Caltech-led researchers find negative cues from appearance alone matter for real elections
5. ASU researchers receive NIH awards for studies of malaria and emergent disease
6. Stanford researchers: Global warming is killing frogs and salamanders in Yellowstone Park
7. Syracuse University researchers discover new way to attack some forms of leukemia
8. Researchers apply systems biology and glycomics to study human inflammatory diseases
9. Researchers at UH explore use of fat cells as heart attack therapy
10. GUMC researchers hone in on new strategy to treat common infection
11. Ben-Gurion University of the Negev researchers help find that hypnosis can induce synesthesia
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/23/2017)... ITHACA, N.Y. , June 23, 2017  IBM ... in dairy research, today announced a new collaboration using ... the chances that the global milk supply is impacted ... project, Cornell University has become the newest academic institution ... Chain, a food safety initiative that includes IBM Research, ...
(Date:5/16/2017)... , May 16, 2017  Veratad Technologies, LLC ( ... online age and identity verification solutions, announced today they ... Conference 2017, May 15 thru May 17, 2017, in ... and International Trade Center. Identity impacts ... and in today,s quickly evolving digital world, defining identity ...
(Date:4/24/2017)... , April 24, 2017 ... and partner with  Identity Strategy Partners, LLP (IdSP) ... "With or without President Trump,s March 6, 2017 ... Terrorist Entry , refugee vetting can be instilled with ... resettlement. (Right now, all refugee applications are suspended ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... , ... October 12, 2017 , ... ... with the pharmaceutical and biotechnology industries to improve patient outcomes and quality of ... trends in analytical testing are being attributed to new regulatory requirements for all ...
(Date:10/11/2017)... ... October 11, 2017 , ... The ... context, enabling overexpression experiments and avoiding the use of exogenous expression plasmids. The ... transformative for performing systematic gain-of-function studies. , This complement to loss-of-function studies, ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... it will be hosting a Webinar titled, “Pathology is going digital. Is your ... on digital pathology adoption best practices and how Proscia improves lab economics and ...
(Date:10/11/2017)... ... , ... Disappearing forests and increased emissions are the main causes of the ... Especially those living in larger cities are affected by air pollution related diseases. , ... pollution-affected countries globally - decided to take action. , “I knew I had to ...
Breaking Biology Technology: