'XMRV' virus could trigger prostate cancer

In a breakthrough study, the research team claimed to have found a virus in human prostate cancer cells that may put men at increased risk of developing the tumor.

The virus, known as xenotropic murine leukemia virus-related virus or XMRV, has been known to trigger leukaemia and other tumors in animals.

Virus linked to Prostate Cancer
Now, the researchers have linked the virus to human prostate cancer, determining that the disease may have a viral origin.

Researchers reporting online in yesterday's Proceedings of the National Academy of Sciences reached their conclusion after examining tissue from the prostates of 233 men with cancer, and subsequently comparing them to 101 non-cancerous prostate-tissue samples.

After studying the data, the research team found that 27 percent of the cancers contained the XMRV virus, which was found in only 6 percent of non-cancerous prostates.

XRMV has been associated with prostate cancer in a previous research but not in such an aggressive way. The latest study strengthens that link.

Although a prostate cancer vaccine is still a distant prospect, researchers say their findings raise hope for the novel ways to diagnose, treat or even prevent this tumor, which affects nearly 200,000 men each year in the U.S.

However, the lead researcher Dr Ila Singh from the pathology department at the University of Utah says that much still remains to be learned about the link between XMRV and prostate cancer.

"We still don't know that this virus causes cancer in people, but that is an important question we are going to investigate,” BBC quoted Dr Singh as saying. “There is a need for a better test to help determine who would benefit from treatment versus who could be left alone.

“If this virus turns out to be a cause for a subset of aggressive tumors, then it would be a good test to use and might be better than PSA.”

"We are already looking at the bodies of 100 women and 100 men, who died from other causes, to see if any other organs carry the virus," she added.

What is XMRV
Xenotropic murine leukemia virus-related virus (XMRV) is a retrovirus like HIV which works by inserting a copy of its own DNA into the chromosomes of a cell they infect. XMRV is known to trigger leukaemia and other tumors in animals.

"One of the things peculiar about this virus is that it has an androgen response element - it grows better in the presence of testosterone and possibly other steroid hormones,” Dr. Singh said.

“This is particularly interesting because if we can prove that it responds to oestrogen it could have a role in other cancers.”

Prostate cancer
Prostate cancer is the most common form of cancer in men in which tumor develops in the prostate gland. In this condition, the prostate cells start becoming abnormal and begin to grow uncontrollably, forming tumors.

This is the second leading cause of cancer-related death in men. The National Cancer Institute estimates that up to 190,000 men in the United States will be diagnosed with prostate cancer this year and 27,000 will die.