Featured Research

from universities, journals, and other organizations

Cancer researchers find key oncoprotein in Merkel cell carcinoma

Date:
August 15, 2011
Source:
University of Pittsburgh Schools of the Health Sciences
Summary:
Researchers have identified the oncoprotein that allows a common and usually harmless virus to transform healthy cells into a rare but deadly skin cancer called merkel cell carcinoma (MCC). Their findings could improve diagnosis for MCC and may help in understanding how other cancers arise.

Researchers at the University of Pittsburgh Cancer Institute (UPCI) have identified the oncoprotein that allows a common and usually harmless virus to transform healthy cells into a rare but deadly skin cancer called Merkel Cell Carcinoma (MCC). Their findings, published August 15 in the Journal of Clinical Investigation, could improve diagnosis for MCC and may help in understanding how other cancers arise.

Three years ago, Yuan Chang, M.D., and Patrick S. Moore, M.D., M.P.H., in the Cancer Virology Program at UPCI, discovered a new human cancer virus, called Merkel Cell polyomavirus (MCV), that causes most cases of MCC. But until now, it was not clear how the virus triggered cancer development.

To figure that out, lead author Masahiro Shuda, Ph.D., UPCI research associate, and the team systematically examined the viral proteins that might trigger cancer cell growth. After establishing human MCC cell lines, the scientists learned that knocking out a viral protein called "small tumor protein," or sT, stopped the cancer cells from replicating. When they introduced sT into healthy cells in the lab, the cells took on the characteristics of cancer cells.

"This was a surprise because the viral sT proteins from other similar viruses that cause cancers in laboratory animals do not directly increase cancer activity in cells," Dr. Shuda said. "Once we found this, we had to next understand the biological mechanisms that make MCV sT a cancer-causing protein, or oncoprotein."

The MCV sT triggers a cellular process called "cap-dependent translation" that allows certain cellular oncoproteins to be made, Dr. Moore explained. Although the cancers caused by MCV are rare, the virus is important because it helps scientists pinpoint cell pathways that are key to more common cancers. These cancers also might activate cap-dependent translation through a DNA mutation rather than through a virus infection.

In related studies recently published by the team in Emerging Infectious Diseases, MCV was shown to normally infect four out of five healthy adults, where it remains a silent resident in skin cells without causing any symptoms. Only when specific mutations occur in the DNA of the virus―for example, by ultraviolet light exposure―does it have potential to cause cancer. The researchers are now working to identify new agents to target MCC cancer cells that may be more active and less toxic.

MCV is the first virus in the family of polyomaviruses shown to cause human cancer, but six other polyomaviruses have recently been discovered as inapparent infections of people, and scientists are actively seeking to find out if they are additional, cancer-causing viruses as well. MCV is the second human cancer virus found by the Chang-Moore laboratory, which previously also discovered the virus causing Kaposi's sarcoma -- the most common cancer among AIDS patients.

Other co-authors are Hyun Jin Kwun, Ph.D., and Huichen Fung, Ph.D., both of the Cancer Virology Program. The research was funded by the National Institutes of Health, the American Cancer Society and UPCI. Dr. Chang is an American Cancer Society Professor of pathology, and Dr. Moore is an American Cancer Society Professor of microbiology and molecular genetics, Pitt School of Medicine.


Story Source:

The above story is based on materials provided by University of Pittsburgh Schools of the Health Sciences. Note: Materials may be edited for content and length.


Cite This Page:

University of Pittsburgh Schools of the Health Sciences. "Cancer researchers find key oncoprotein in Merkel cell carcinoma." ScienceDaily. ScienceDaily, 15 August 2011. <www.sciencedaily.com/releases/2011/08/110815121338.htm>.
University of Pittsburgh Schools of the Health Sciences. (2011, August 15). Cancer researchers find key oncoprotein in Merkel cell carcinoma. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2011/08/110815121338.htm
University of Pittsburgh Schools of the Health Sciences. "Cancer researchers find key oncoprotein in Merkel cell carcinoma." ScienceDaily. www.sciencedaily.com/releases/2011/08/110815121338.htm (accessed September 16, 2014).

Share This



More Health & Medicine News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

EU Ministers and Experts Meet to Discuss Ebola Reponse

EU Ministers and Experts Meet to Discuss Ebola Reponse

AFP (Sep. 15, 2014) The European Commission met on Monday to coordinate aid that the EU can offer to African countries affected by the Ebola outbreak. Duration: 00:58 Video provided by AFP
Powered by NewsLook.com
Despite The Risks, Antibiotics Still Overprescribed For Kids

Despite The Risks, Antibiotics Still Overprescribed For Kids

Newsy (Sep. 15, 2014) A new study finds children are prescribed antibiotics twice as often as is necessary. Video provided by Newsy
Powered by NewsLook.com
FDA Eyes Skin Shocks Used at Mass. School

FDA Eyes Skin Shocks Used at Mass. School

AP (Sep. 15, 2014) The FDA is considering whether to ban devices used by the Judge Rotenberg Educational Center in Canton, Massachusetts, the only place in the country known to use electrical skin shocks as aversive conditioning for aggressive patients. (Sept. 15) Video provided by AP
Powered by NewsLook.com
Respiratory Virus Spreads To Northeast, Now In 21 States

Respiratory Virus Spreads To Northeast, Now In 21 States

Newsy (Sep. 14, 2014) The respiratory virus Enterovirus D68, which targets children, has spread from the Midwest to 21 states. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins