The Retrovirus XMRV in Prostate Cancer and Beyond

Robert H Silverman, FASEB J., April 2011:

Cancer Biology, Cleveland Clinic, Cleveland, OH

Genetic evidence that the antiviral protein, RNase L, suppresses hereditary prostate cancer led us to examine the possibility that chronic viral infections might predispose men to prostate cancer. These studies resulted in identification of a previously unknown gammaretrovirus, xenotropic murine leukemia virus-related virus (XMRV).

Currently, several different research teams have published both PCR-based and non-PCR-based evidence in support of the hypothesis that XMRV is a bona fide human virus. In addition, some but not all studies associated XMRV infections with either prostate cancer or chronic fatigue syndrome-myalgic encephalomyelitis (CFS-ME). XMRV replication is stimulated by androgen and inhibited by interferon through host restriction factors, such as apobec3, tetherin and RNase L.

Studies in rhesus macaques showed that intravenous inoculation with XMRV caused wide-spread dissemination of the virus in lymphoid and non-lymphoid tissues (including prostate), a humoral immune response and a chronic persistent infection.

While gammaretroviruses cause cancer and neurological disease in animals it remains unknown if XMRV is a cause of either prostate cancer or CFS-ME.