Cancer-Associated Viruses Overblown?

An MD Anderson study calls into question estimates on the percentage of viruses linked to cancer.

Tracy Vence
Aug 7, 2013

WIKIMEDIA, CENTERS FOR DISEASE CONTROL AND PREVENTIONNumerous studies have come out in recent years linking certain viruses to cancer, highlighting the immune system’s role in staving off—and at times, succumbing to—potential malignancies. But according to a paper appearing this month in the Journal of Virology, researchers may have overestimated the percentage of viruses associated with cancer.

Using samples from The Cancer Genome Atlas, Xiaoping Su and his colleagues at the University of Texas MD Anderson Cancer Center sequenced RNA from 3,775 malignant tumors and used a bioinformatics approach to locate viral transcripts. The researchers also mined the data for viral integration sites within the host genome.

All told, their findings suggest fewer cancers may be associated with DNA viruses than previously estimated. While they did find traces of human papillomavirus in head-and-neck squamous cell carcinoma, uterine endometrioid carcinoma, and squamous cell carcinoma of the lung, and evidence of hepatitis B virus and Epstein-Barr virus in hepatocellular carcinoma and gastric carcinoma tumors, respectively, the researchers found that most of the common cancers they studied did not contain traces of DNA viruses at all.

“The search for virus associations in these malignancies has consumed the efforts of many investigators,” Su said in a statement. Now, he suggested, scientists might consider focusing their efforts elsewhere.

At any rate, he noted that bioinformatics is an important tool for identifying potential convections between viruses and cancers. “This study highlights the importance of bioinformatics in defining the landscape of virus integration across cancer subtypes,” said Su.