title: No association between XMRV or related gammaretroviruses in Australian prostate cancer patients.
abstract: BACKGROUND
  Xenotropic murine leukemia virus-related virus (XMRV) is a gammaretrovirus reported to be associated with prostate cancer (PC) and chronic fatigue syndrome (CFS). While the association of XMRV with CFS and PC has recently been discredited, no studies have been performed in Australian patients to investigate the association between PC and XMRV or related murine leukemia virus (MLV) in matched PC and normal tissue.
  
  
  METHODS
  Genomic DNA (gDNA) was purified from matched normal and cancer formalin-fixed paraffin-embedded (FFPE) prostate tissue from 35 Australian PC patients with Gleason scores ranging from 7 - 10. The presence of the ribonuclease L (RNase L) polymorphism R462Q was determined by allele specific PCR. Samples were screened for XMRV and related murine leukemia virus (MLV) variants by qPCR. Contaminating mouse DNA was detected using qPCR targeting mouse intracisternal A particle long terminal repeat DNA.
  
  
  RESULTS
  gDNA was successfully purified from 94% (66/70) of normal and cancer FFPE prostate tissues. RNase L typing revealed 8% were homozygous (QQ), 60% were heterozygous (RQ) and 32% were wild-type (RR) for the RNase L mutation. None of the 66 samples tested were positive for XMRV or related MLV sequences using broad MLV or XMRV specific primers with detection sensitivities of 1 viral copy of MLV/XMRV and XMRV DNA, respectively.
  
  
  CONCLUSIONS
  Using highly sensitive qPCR we found no evidence of XMRV or related gammaretroviruses in prostate tissues from 35 Australian PC patients. Our findings are consistent with other studies demonstrating that XMRV is a laboratory contaminant that has no role in the aetiology of PC.
authors.affiliation: Retroviral Biology and Antivirals Laboratory, Centre for Virology, Burnet Institute, 85 Commercial Road, Melbourne, Victoria 3004, Australia.
authors.forename: Simin D
authors.initials: SD
authors.lastname: Rezaei
authors.forename: Anna C
authors.initials: AC
authors.lastname: Hearps
authors.forename: John
authors.initials: J
authors.lastname: Mills
authors.forename: John
authors.initials: J
authors.lastname: Pedersen
authors.forename: Gilda
authors.initials: G
authors.lastname: Tachedjian
mesh_terms: D000368:Aged; D001315:Australia; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000821:virology; D011471:Prostatic Neoplasms / Q000209:etiology* / Q000821:virology*; D060888:Real-Time Polymerase Chain Reaction; D012192:Retroviridae Infections / Q000150:complications* / Q000821:virology*; D058008:Xenotropic murine leukemia virus-related virus / Q000302:isolation & purification* / Q000472:pathogenicity*