Prostate virus appears to be infectious, found in men with prostate cancer

The recently discovered infectious virus XMRV was found in two patients with prostate cancer, according to a study published in the Proceedings of the National Academy of Sciences.

The findings establish XMRV as a new human retrovirus, the study’s authors say. Upon entering a host cell, retroviruses, such as XMRV, produce viral DNA that inserts into the host's DNA, prompting the formation of more, identical viruses.

"These results are significant in that they validate that XMRV has infected humans," said Robert Silverman, PhD, of the Cleveland Clinic Lerner Research Institute, who led the study. "Future studies will determine whether XMRV is a contributing factor to the development of prostate cancer. If it is, the presence of XMRV could be an early indicator for prostate cancer and a possible therapeutic target."

Cleveland Clinic researchers and collaborators from the University of California, San Francisco first reported the identification of XMRV in prostate cancer in February 2006. However, until now, it was undetermined whether XMRV was an infectious virus. In this new study, XMRV generated from a patient's RNA was shown to infect human prostate cancer cells in the lab, resulting in the production of new virus particles. The presence of XMRV in two prostate cancer patients was confirmed by determining the precise locations in the human genome where the virus DNA inserted itself.