Navigation Links
U of T researchers map role of Epstein-Barr virus in cancer

Researchers at the University of Toronto have mapped the molecular details that show how a viral protein coded in the Epstein-Barr virus immortalizes cells and causes them to continuously grow, thereby predisposing people to certain types of cancer.

"Epstein-Barr virus (EBV) is one of the most common human viruses in the world and is strongly linked to certain b-cell cancers like Burkitt's lymphoma as well as the epithelial cell cancer, nasopharyngeal carcinoma. EBNA1 is a protein coded in the Epstein-Barr virus and suspected to play a role in the development of cancer," says Lori Frappier, professor in medical genetics and microbiology at U of T and senior author of a paper in the April 1 issue of Molecular Cell.

"This research shows how EBNA1 interferes with natural cell growth regulation by binding to a particular protein in cells, causing them to continue growing and therefore increasing the risk of becoming cancerous."

Frappier explains that all cells contain the two proteins ?p53 and USP7 ?that work together to regulate cell growth. P53 is an important protein whose level in the cell determines whether cells will continue to proliferate or stop dividing and die. USP7 is a protein that binds to p53 and makes it stable. Under those conditions, cells stop growing and die, which is a natural state of cell regulation. Once EBNA1 is introduced to cells, however, this protein interferes with natural cell regulation by binding to USP7 and preventing its interaction with the p53 protein.

"Normally, p53 levels will increase in response to certain problems in the cell such as damaged DNA and this stops the cell from proliferating. Through binding USP7, EBNA1 keeps the p53 levels low so cells will continue to divide when they shouldn't, which means they're now more likely to develop into cancer," Frappier says.

"All viruses known to be able to cause cancer, like the human papillomavirus that causes cervical cancer for example, have b een shown to work through this p53 protein, but up until now, no one's ever found any regulation of p53 that's associated with the Epstein-Barr virus. That was surprising because all other viruses that stimulate cell proliferation do it through p53. The question was why this one didn't. What our research shows is that EBNA1 does actually impact on the p53 protein; it just does it in a different way than other viruses do."

Frappier, a Canada Research Chair in Molecular Virology, also conducted this research with Professor Aled Edwards, also of medical genetics and microbiology at U of T, and Professor Cheryl Arrowsmith, of medical biophysics at U of T and the Ontario Cancer Institute. Both Edwards and Arrowsmith are also from U of T's Banting and Best Department of Medical Research and the Structural Genomics Consortium.

The researchers tested the effects of EBNA1 on human cells grown in culture. Frappier says the paper provides a structural explanation of this protein complex so scientists can see in molecular detail how the EBNA1 protein binds to USP7 and the resulting impact on cell growth. Once that level of detail is achieved, she says scientists can then design specific mutations in these proteins to see what happens to cells when the proteins don't interact with one another. A better understanding of these molecular mechanisms will hopefully lead scientists and researchers to developing better methods of combating viruses like these which cause disease, says Frappier.


'"/>

Source:University of Toronto


Related biology news :

1. NYU researchers simulate molecular biological clock
2. Vital step in cellular migration described by UCSD medical researchers
3. ASU researchers finds novel chemistry at work to provide parrots vibrant red colors
4. UCSD researchers maintain stem cells without contaminated animal feeder layers
5. Why do insects stop breathing? To avoid damage from too much oxygen, say researchers
6. New protein discovered by Hebrew University researchers
7. First real-time view of developing neurons reveals surprises, say Stanford researchers
8. Agilent Technologies releases automated literature search tool for biology researchers
9. Self-assembled nano-sized probes allow Penn researchers to see tumors through flesh and skin
10. Yale researchers identify molecule for detecting parasitic infection in humans
11. US life expectancy about to decline, researchers say
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:5/16/2016)... NEW YORK , May 16, 2016   ... authentication solutions, today announced the opening of an IoT ... to strengthen and expand the development of embedded ... provides an unprecedented level of convenience and security with ... to authenticate one,s identity aside from DNA. EyeLock,s platform ...
(Date:4/28/2016)... 28, 2016 First quarter 2016:   ... compared with the first quarter of 2015 The gross ... M (loss: 18.8) and the operating margin was 40% (-13) ... Cash flow from operations was SEK 249.9 M (21.2) , ... is unchanged, SEK 7,000-8,500 M. The operating margin for ...
(Date:4/15/2016)... DUBLIN , April 15, 2016 ... of the,  "Global Gait Biometrics Market 2016-2020,"  report ... http://photos.prnewswire.com/prnh/20160330/349511LOGO ) , ,The global gait ... CAGR of 13.98% during the period 2016-2020. ... movement angles, which can be used to compute ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... PHILADELPHIA , June 27, 2016  Liquid ... today announced the funding of a Sponsored Research ... study circulating tumor cells (CTCs) from cancer patients.  ... changes in CTC levels correlate with clinical outcomes ... therapies. These data will then be employed to ...
(Date:6/24/2016)... ... , ... While the majority of commercial spectrophotometers and fluorometers use the z-dimension ... are higher end machines that use the more unconventional z-dimension of 20mm. Z-dimension ... bottom of the cuvette holder. , FireflySci has developed several Agilent flow cell ...
(Date:6/23/2016)... CAMBRIDGE, Mass. , June 23, 2016 /PRNewswire/ ... the development of novel compounds designed to target ... compound, napabucasin, has been granted Orphan Drug Designation ... in the treatment of gastric cancer, including gastroesophageal ... cancer stemness inhibitor designed to inhibit cancer stemness ...
(Date:6/23/2016)... ... 23, 2016 , ... Charm Sciences, Inc. is pleased to ... AOAC Research Institute approval 061601. , “This is another AOAC-RI approval of the ... Vice President of Regulatory and Industrial Affairs. “The Peel Plate methods perform comparably ...
Breaking Biology Technology: