Xenotropic murine leukemia virus-related virus: current research, disease associations and therapeutic opportunities

Judy A Mikovits, Vincent C Lombardi and Francis W Ruscetti

Despite the fact that xenotropic murine leukemia virus-related virus (XMRV) research is in its infancy, considerable attention has been focused on this recently discovered human retrovirus because of the surprising association of XMRV with two very different diseases: prostate cancer and myalgic encephalomyelitis/chronic fatigue syndrome. Like other retroviral infections, XMRV integrates into hostcell DNA and thus endures for a lifetime. Little is known about host-cell interactions, reservoirs of infection or the lifecycle of XMRV. Information on murine xenotropic viruses, as well as current research on cellular tropism and cis-acting glucocorticoid response elements, provides intriguing clues for viral persistence, mechanisms of pathogenesis and opportunities for XMRV as a diagnostic biomarker and therapeutic target in myalgic encephalomyelitis/chronic fatigue syndrome.