The value of the ratio of transmembrane protease serine 2 and ETS-related gene fusion transcripts in the diagnosis of prostate cancer

Abstract

-Objective To evaluate the diagnostic value of the ratio of transmembrane protease serine 2 (TMPRSS2) and ErS-related gene (ERG)'s fusion transcripts to PSA mRNA in prostate cancer. Methods A fluorescence quantitative reverse transcript (FQ-RT)-PCR method for detection of the ratio of TMPRSS2: ERG fusion transcripts to PSA mRNA was established. TMPRSS2: ERG transcripts and PSA mRNA in urine samples obtained from 99 patients with prostate cancer (PCa) and 107 patients with benign prostate hyperplasia (BPH) were detected by FQ-RT-PCR, and the ratio of TMPRSS2:ERG mRNA to PSA mRNA was calculated by 2-△Ct. The diagnostic efficacy of TMPRSS2: ERG in urine was evaluated. The correlations of the ratio of TMPRSS2: ERG mRNA to PSA mRNA with clinical and pathological grades were investigated. Results The ratio of TMPRSS2: ERG mRNA to PSA mRNA was significantly higher in PCa group than that in BPH group (0.101 vs 0.000, U=2 290.500, P 0.05). The area under curve (AUC) was 0.784 (95% CI:0.707～0.860). When cutoff value of the ratio of TMPBSS2: ERG mRNA to PSA mRNA was 3.0×105, the diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy rate were 75.8% (75/99), 94.4% (101/107), 92. 6% (75/81), 80.8% (101/125) and 85.4% (176/206), respectively. But the sensitivity was not correlated with PSA, Gleason grade and clinical stage (χ2=3.572, 2.278,3.707 respectively,P>0.05). Conclusions The ratio of TMPBSS2:ERG mRNA to PSA mRNA in the urine has certain sensitivity and specificity in the diagnosis of PCa. It can be used as a potential marker in the diagnosis of PCa. However, it can not be used as an index to monitor tumor progression or prognosis in PCa patients. Key words: Prostatic neoplasms; Serine endopeptidases; Proto-oncogene proteins c-ets; Oncogene peoteins; fusion; Reverse transcriptase polymerase chain reaction