1274 A PRELIMINARY SCREENING OF XENOTROPIC MURINE LEUKEMIA VIRUS-RELATED VIRUS IN JAPANESE PROSTATE CANCER PATIENTS

Abstract

INTRODUCTION AND OBJECTIVES: Recently, a new gammaretrovirus, xenotropic murine leukemia virus-related virus (XMRV), was detected in prostatic tissue in patients with familial prostate cancer, specifically in patients homozygous for a missense mutation in the RNase L gene, R462Q. More recent report revealed that polytropic murine leukemia virus-related virus (polytropic MLV) gene sequences were frequently detected in chronic fatigue syndrome patient. These reports are mainly from western countries, thus it is not clear that the actual prevalence of XMRV or other types of MLV infection in Japanese male. Here, we attempt to examine the infection status of MLV in Japanese with prostate cancer. METHODS: A total of 61 prostate biopsy specimens were used for this study. RNA samples were prepared from these prostate biopsy tissues, and were screened for the presence of MLV-specific env sequences using highly sensitive RT and nested PCR approach. RESULTS: MLV sequences were detected in four out of sixty one patients (6.7%). Of these four positive cases, XMRV was detected in one. And in the other three cases, polytropic MLV gene sequence was detected. The clinical diagnosis of XMRV positive case was cT2bN0M0, Gleason score 4 4 8, PSA 20.7 ng/ml with no family history for prostate cancer. Subsequently, blood sample from this patient was analyzed, however, XMRV was not detected. Three polytropic MLV detected cases included 2 positive and one negative for prostate cancer. CONCLUSIONS: Our results suggest relatively lower rate of existence for XMRV in prostatic tissue of Japanese prostate cancer patients. In addition, there also exists a possibility of polytropic MLV infection in Japanese prostate cancer patients, and it may be the first report regarding polytropic MLV gene sequence detection in Japanese male.