Percentage of cancers linked to viruses potentially overestimated

August 5, 2013

The results of a large-scale analysis of the association between DNA viruses and human malignancies suggest that many of the most common cancers are not associated with DNA viruses. The findings, published in the August 2013 issue of the Journal of Virology, challenge earlier studies suggesting as high as 40 percent of tumors are caused by viruses.

For years scientists believed viruses played a role in the development of maybe 10 to 20 percent of cancers. In 2011, scientists at the Karolinska Institute in Sweden identified potential viral links to several cancers not previously associated with viruses, including and , suggesting the real number could be as high as 40 percent. Since then, researchers have been working hard to find more associations, in part because viruses could provide targets for vaccines to prevent or cure these cancers.

To better understand the role of DNA viruses in human cancers, researchers from the MD Anderson Cancer Center in Houston sequenced RNA from 3775 malignant tumor samples from The Cancer Genome Atlas and then applied a robust bioinformatics algorithm to survey them for the presence of viral transcripts.

Those cancers not associated with DNA viruses included , cutaneous , low and high-grade gliomas of the brain (the latter killed Senator Edward Kennedy), and adenocarcinomas of the breast, colon and rectum, lung, prostate, ovaries, kidneys, and thyroid.

The findings, says Xiaoping Su, an author on the study, suggest the estimate that 40 percent of tumors are virus-related "should be much lower."

"The search for virus associations in these malignancies has consumed the efforts of many investigators," says Su, implying that his large-scale effort will spare researchers fruitless investigations.

The study also provides the framework for understanding how viruses integrate into cancer subtypes such as hepatocellular cancer, says Su. That might make it possible to personalize treatments by targeting genes that are located within known integration sites and that might be drivers of cancer initiation and progression. A key finding was that there are specific sites where integrate into the host genome prior to initiating cancer, and that these sites are frequently located within particular host genes.

"This study highlights the importance of bioinformatics in defining the landscape of virus integration across cancer subtypes," says Su.

Explore further: Hidden strains of HPV found in 'virus-negative' genital warts

More information: www.asm.org/images/Communicati … /0713viruscancer.pdf

Related Stories

Hidden strains of HPV found in 'virus-negative' genital warts

July 11, 2013
There are 170 established HPV types. Cancerous human papillomavirus (HPV) viruses are the main cause of cervical cancer, and are found in close to 100% of cervical tumors.

Ancient viruses that function in early human development may play role in cancer

July 31, 2013
The St. Laurent Institute, a non-profit medical research institute focused on the systems biology of disease, today announced in a study published in the July edition of Genome Biology, that genetic matter, previously ignored ...

Researchers find that proteins involved in immunity potentially cause cancer

July 14, 2013
A set of proteins involved in the body's natural defenses produces a large number of mutations in human DNA, according to a study led by researchers at the National Institutes of Health. The findings suggest that these naturally ...

Researchers discover gene that suppresses herpesviruses

February 13, 2013
Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) hide within the worldwide human population. While dormant in the vast majority of those infected, these active herpesviruses can develop into several ...

Pressurized virus blasts its infectious DNA into human cells

July 24, 2013
The virus that causes those painful lip blisters known as cold sores has an internal pressure eight times higher than a car tire, and uses it to literally blast its infectious DNA into human cells, scientists are reporting ...

Viruses kill pancreatic tumors in preclinical model

March 20, 2012
(Medical Xpress) -- An intra-tumor injection of a virus prevented further growth of some pancreatic tumors and eradicated others in mouse models of pancreatic ductal adenocarcinoma. However, some tumors continued growing ...

Recommended for you

New therapeutic approach for difficult-to-treat subtype of ovarian cancer identified

July 24, 2017
A potential new therapeutic strategy for a difficult-to-treat form of ovarian cancer has been discovered by Wistar scientists. The findings were published online in Nature Cell Biology.

Anti-cancer chemotherapeutic agent inhibits glioblastoma growth and radiation resistance

July 24, 2017
Glioblastoma is a primary brain tumor with dismal survival rates, even after treatment with surgery, chemotherapy and radiation. A small subpopulation of tumor cells—glioma stem cells—is responsible for glioblastoma's ...

Immune cells the missing ingredient in new bladder cancer treatment

July 24, 2017
New research offers a possible explanation for why a new type of cancer treatment hasn't been working as expected against bladder cancer.

No dye: Cancer patients' gray hair darkened on immune drugs

July 21, 2017
Cancer patients' gray hair unexpectedly turned youthfully dark while taking novel drugs, and it has doctors scratching their heads.

Shooting the achilles heel of nervous system cancers

July 20, 2017
Virtually all cancer treatments used today also damage normal cells, causing the toxic side effects associated with cancer treatment. A cooperative research team led by researchers at Dartmouth's Norris Cotton Cancer Center ...

Immune-cell numbers predict response to combination immunotherapy in melanoma

July 20, 2017
Whether a melanoma patient will better respond to a single immunotherapy drug or two in combination depends on the abundance of certain white blood cells within their tumors, according to a new study conducted by UC San Francisco ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.