MP23-14 FUNCTIONAL SIGNIFICANCE OF TUMOR SUPPRESSIVE MICRORNA-143/145 CLUSTER IN RENAL CELL CARCINOMA

Abstract

You have accessJournal of UrologyKidney Cancer: Basic Research I1 Apr 2014MP23-14 FUNCTIONAL SIGNIFICANCE OF TUMOR SUPPRESSIVE MICRORNA-143/145 CLUSTER IN RENAL CELL CARCINOMA Hideki Enokida, Hirofumi Yoshino, Takeshi Chiyomaru, Toshihiko Itesako, Naohiko Seki, and Masayuki Nakagawa Hideki EnokidaHideki Enokida More articles by this author , Hirofumi YoshinoHirofumi Yoshino More articles by this author , Takeshi ChiyomaruTakeshi Chiyomaru More articles by this author , Toshihiko ItesakoToshihiko Itesako More articles by this author , Naohiko SekiNaohiko Seki More articles by this author , and Masayuki NakagawaMasayuki Nakagawa More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.882AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Our recent studies of microRNA (miRNA) expression signatures have demonstrated that the miRNA-143/145 cluster is significantly downregulated in several types of cancer and represents a putative tumor-suppressive miRNA in human cancers. The aim of this study was to investigate the functional significance of the miR-143/145 cluster in cancer cells and to identify novel molecular targets of the miR-143/145 cluster in renal cell carcinoma (RCC). METHODS We evaluated miR-143 and miR-145 expressions in 18 pair of clear cell RCC and adjacent noncancerous tissues by stem-loop RT-PCR. We performed gain-of-function studies (cell migration and invasion assays) by mature miRNAs transfection into RCC cell lines (786-O and A498). To identify the biological processes or pathways potentially regulated by the miR-143/145 cluster, we applied genome-wide gene expression analysis and in silico study; TargetScan database and GENECODIS software, which assigned a number of the putative miRNA targets to known pathways in KEGG. Furthermore, we performed gene expression analyses of all candidate genes involved in each of the pathways by using microarray expression data containing 53 clear cell RCCs and 23 noncancerous kidney tisuues, and constructed heat map diagrams. RESULTS The expression levels of miR-143 and miR-145 were significantly downregulated in RCC tissues compared with adjacent noncancerous tissues. A significant positive correlation was recognized between miR-143 and miR-145 expression. Restoration of mature miR-143 or miR-145 in 786-O and A498 RCC cells revealed that both mature miRNAs significantly inhibited cancer cell proliferation and invasion, suggesting that the miR-143/145 cluster functioned as a tumor suppressor in RCC. Gene expression data and in silico database analysis implied several promising target genes of the cluster, including hexokinase-2 (HK2) gene, which encodes a glycolytic enzyme crucial for the Warburg effect in cancer cells. Luciferase reporter assays showed that both miR-143 and miR-145 directly regulated HK2. In clinical RCC specimens, the expression of HK2 was significantly higher in cancer tissues than in noncancerous tissues. Silencing HK2 RCC enhanced cell proliferation and invasion, suggesting that HK2 has oncogenic functions in RCC. CONCLUSIONS Thus, our data demonstrated that loss of the tumor-suppressive miR-143/145 cluster enhanced RCC cell proliferation and invasion through targeting HK2 that is crucial for the Warburg effect. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e248 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Hideki Enokida More articles by this author Hirofumi Yoshino More articles by this author Takeshi Chiyomaru More articles by this author Toshihiko Itesako More articles by this author Naohiko Seki More articles by this author Masayuki Nakagawa More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...