1321 THE BIOMARKER MIR-221 REGULATES STAT1 SIGNALING IN PROSTATE CANCER BY TARGETING IRF2 (2012)

You have accessJournal of UrologyProstate Cancer: Basic Research II1 Apr 20121321 THE BIOMARKER MIR-221 REGULATES STAT1 SIGNALING IN PROSTATE CANCER BY TARGETING IRF2 Martin Spahn, Markus Krebs, Maria Schubert, Hubertus Riedmiller, and Burkhard Kneitz Martin SpahnMartin Spahn Würzburg, Germany More articles by this author , Markus KrebsMarkus Krebs Würzburg, Germany More articles by this author , Maria SchubertMaria Schubert Würzburg, Germany More articles by this author , Hubertus RiedmillerHubertus Riedmiller Würzburg, Germany More articles by this author , and Burkhard KneitzBurkhard Kneitz Würzburg, Germany More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.1668AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We have recently shown that miR221 is a new biomarker to predict cancer specific survival in high risk prostate cancer. Aim of this study was to elucidate miR221-mediated pathways. METHODS We transiently transfected PCa cell lines (PC3,DU145,LNCaP) with pre-miR221 in order to reconstitute mature miR221 expression. Microarray-based genome-wide mRNA profiling was performed from transfected and control cells. Bioinformatical annotation of microarray data were used to identify genes diffenrenntially expressed in miR-221 transfected vs. control cells. Furthermore, expression of dysregulated genes was confirmed by RT-PCR and Western Blotting. To understand how reconstitution of miR221 enhances STAT1-mediated signaling, we were looking for bioinformatically predicted miR221-targets being able to repress STAT1 signaling and confirmed these by Luciferase assay and Western Blotting. RT-PCR analysis of gene expression in native tumors were performed to proof the correlation between IRF1, IRF2 and miR-221 levels. RESULTS Transfection of cells (PC3,DU145,LNCaP) with pre-miR-221 led to a strong induction of apoptosis and a significant growth arrest. Microarray-based genome-wide mRNA profiling showed an upregulation of 585 genes–among these a plethora of interferon-related genes–and downregulation of 306 genes. Bioinformatical annotation of microarray data confirmed a highly significant involvement of genes related to immune response and apoptosis. Furthermore,expression of dysregulated genes was confirmed by RT-PCR (STAT1, IRF1, IRF9) and Western Blotting (STAT1, Phospho-STAT1, Phospho-PKR). To understand how reconstitution of miR221 enhances STAT1-mediated signaling, we were looking for bioinformatically predicted miR221-targets being able to repress STAT1 signaling. We introduce IRF2 as a new direct target of miR221 using Luciferase assay and Western Blotting. Consistently, RT-PCR analysis of gene expression in native tumors showed an inverse correlation between IRF1 and IRF2 with a significantly low expression of IRF2 in tumors with high miR221-levels. CONCLUSIONS Our results suggest that the tumor-suppressive function of miR221 bases on the repression of IRF2, an antagonist of the STAT1-IRF1 signaling axis and known oncogene in other malignancies. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e535-e536 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Martin Spahn Würzburg, Germany More articles by this author Markus Krebs Würzburg, Germany More articles by this author Maria Schubert Würzburg, Germany More articles by this author Hubertus Riedmiller Würzburg, Germany More articles by this author Burkhard Kneitz Würzburg, Germany More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...