Virus could cause prostate cancer, says new research

Published on Monday 7 September 2009 22:03

A VACCINE against prostate cancer has moved a step closer after scientists discovered the disease may be caused by a virus.

Researchers who examined more than 300 tumours taken from patients found an infection known as XMRV (xenotropic murine leukaemia virus) in just under a third.

The virus was more likely to be present in aggressive cancers – adding extra significance to the findings, which are published in Proceedings of the National Academy of Sciences.

The infectious nature of the virus raises the question that it could be contagious – perhaps transferred through sex.

If the virus does cause prostate cancer, it could pave the way for early screening, antiviral medications – such as those that treat HIV – and even a vaccine, according to scientists.

Pathologist Professor Ila Singh, of Utah University, said: "The recognition that human papilloma viruses most often initiate cervical carcinomas has focused efforts on viral detection for early diagnosis and on preventive vaccination.

"Similarly, a determination that a retrovirus can cause prostate cancer would focus efforts on preventing transmission, antiviral therapy, and vaccine development."

Viruses are already blamed for causing some liver cancers and cervical cancer.

The researchers classified the virus as a gamma-retrovirus. These are known to cause leukeamias and soft tissue cancers in many animal species but have not yet been shown to cause tumours in humans.

Prostate cancer is Britain's most common cancer among men and the second highest killer, after lung cancer.

Some 35,000 people a year are diagnosed with it – and 12,000 die.

There are two types, aggressive and non-aggressive. The aggressive type is usually fatal within 18 months.

Experts said more research was needed, but described the findings as "exciting".

Dr Chris Parker, Cancer Research UK's prostate cancer expert at the Institute of Cancer Research, said: "This exciting study finds a virus, similar to that which can cause certain cancers in animals, in human prostate cancer cells.

"It raises the possibility that the virus might contribute to the development of some prostate cancers. Right now, this is a possibility that needs to be tested.

"But in the future, if it turns out to be true, then we could speculate about the possibility of vaccination to protect against prostate cancer, similar to the approach now used to prevent cervical cancer."

The Prostate Cancer Charity described the study as "intriguing" but said much more research is needed to establish whether the virus is a cause.

Head of research management Dr Helen Rippon said: "The findings of this new study into the XMRV virus are intriguing but do pose several key questions about the role the infection has to play in prostate cancer.

"Most significantly, the researchers are yet to discover whether the virus is a cause, an effect or simply an innocent bystander in the development of the disease.

"It will still be some time until it is understood whether the XMRV virus is a potential cause of prostate cancer. We look forward to the results of further studies examining this."

No respector of wealth or class

PROSTATE cancer tends to develop in males over 50 and is one of the most common cancers affecting men. Famous people diagnosed with prostate cancer include the singer and actor, Harry Belafonte, who had surgery and now lectures on his experiences to raise awareness. Oscar-winning director Robert De Niro was diagnosed at the age of 60. The early discovery of his cancer was attributed to regular checkups.