title: Do microRNA 96, 145 and 221 expressions really aid in the prognosis of prostate carcinoma?
abstract: MicroRNAs (miRs) are small noncoding RNAs that have been reported to be promising diagnostic tools. We used quantitative real-time reverse transcription PCR (RT-qPCR) to analyze differentially expressed miRNAs in prostate tumor samples to determine its prognostic value. From 2007 to 2009, tumor tissues were obtained from 73 radical prostatectomy specimens. Differentially expressed miR-96, -145 and -221 were validated by TaqMan RT-qPCR using all 73 tissues. The prognostic value was assessed in terms of biochemical recurrence using Kaplan-Meier and Cox regression analyses. For our patient cohort, the mean age was 64.7 years (50-76 years) and the mean prostate-specific antigen (PSA) was 7.5 ng ml(-1). During the follow-up period (mean, 19.4 months), 14 of 73 (19.2%) patients developed biochemical recurrence. Expression of miR-96, -145 and -221 correlated strongly with each other, but there were no correlations between miRNA expression and clinicopathologic parameters. Kaplan-Meier survival curves using the log-rank test showed a decreased biochemical recurrence-free interval with pathologic stage (P<0.001). In addition, patients with Gleason scores over 8, compared with those with a Gleason score of 6, showed a decreased biochemical recurrence-free interval in Kaplan-Meier analysis (P=0.001). However, expression of miR-96, -145 and -221 did not correlate with the biochemical recurrence interval in Kaplan-Meier survival curves or by multivariate analysis using the Cox proportional hazard regression model, either. In conclusion, we did not observe a significant correlation between the expression of miR-96, -145 and -221 and clinicopathologic parameters. To utilize miRNA as a diagnostic tool in clinical practice, more research is needed to understand miRNA mechanisms, identify miRNA targets, and further characterize miRNA function.
authors.affiliation: Department of Urology, Korea University College of Medicine, Seoul 136-705, Republic of Korea.
authors.forename: Sung Gu
authors.initials: SG
authors.lastname: Kang
authors.forename: Young Ran
authors.initials: YR
authors.lastname: Ha
authors.forename: Seo Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Seok Ho
authors.initials: SH
authors.lastname: Kang
authors.forename: Hong Seok
authors.initials: HS
authors.lastname: Park
authors.forename: Jeong Gu
authors.initials: JG
authors.lastname: Lee
authors.forename: Jun
authors.initials: J
authors.lastname: Cheon
authors.forename: Chul Hwan
authors.initials: CH
authors.lastname: Kim
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000235:genetics / Q000473:pathology*; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D014408:Biomarkers, Tumor; D035683:MicroRNAs; C541010:MIRN145 microRNA, human; C525709:MIR221, human; C541492:MIRN96 microRNA, human