title: Expression of the tumor suppressive miRNA-23b/27b cluster is a good prognostic marker in clear cell renal cell carcinoma.
abstract: OBJECTIVE
  We observed abnormal expression of the microRNA-23b/27b (miR-23b/27b) cluster in our previous study of miRNA expression signatures. However, the relationship between aberrant miRNA expression and clear cell renal cell carcinoma is not well established. We investigated the functional significance of the miR-23b/27b cluster in clear cell renal cell carcinoma cells and evaluated these miRNAs as biomarkers to predict the risk of clear cell renal cell carcinoma.
  
  
  METHODS
  Expression levels of miR-23b and miR-27b were determined by quantitative real-time reverse transcriptase-polymerase chain reaction. The association between miRNA expression and overall survival was estimated by the Kaplan-Meier method. Gain of function assays were performed using mature miR-23b and miR-27b in the 786-O and A498 renal cell carcinoma cell lines. Targets regulated by these miRNAs were predicted by in silico analysis.
  
  
  RESULTS
  Expression of the miR-23b/27b cluster was significantly decreased in clear cell renal cell carcinoma tissue specimens and associated with pathological grade and stage. Significantly shorter overall survival was observed in patients with lower expression of the miR-23b/27b cluster. Restoration of miR-23b and miR-27b significantly inhibited cancer cell proliferation, migration and invasion.
  
  
  CONCLUSIONS
  Expression of the miR-23b/27b cluster was frequently decreased in clear cell renal cell carcinoma tissue. Reduced expression of these miRNAs increased the risk of disease progression and predicted poor survival. Thus, miR-23b and miR-27b function as tumor suppressors, targeting several oncogenic genes in clear cell renal cell carcinoma cells.
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ishihara
authors.affiliation: Department of Functional Genomics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Seki
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Inoguchi
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yoshino
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Tatarano
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Yasutoshi
authors.initials: Y
authors.lastname: Yamada
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Itesako
authors.affiliation: Department of Functional Genomics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Goto
authors.affiliation: Department of Functional Genomics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Rika
authors.initials: R
authors.lastname: Nishikawa
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakagawa
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan. Electronic address: enokida@m.kufm.kagoshima-u.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Enokida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000378:metabolism*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism*; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis*; D008875:Middle Aged; D014407:Tumor Cells, Cultured
chemical_list: C552430:MIRN23a microRNA, human; C531388:MIRN27 microRNA, human; D035683:MicroRNAs
keywords: MIRN23 microRNA; MIRN27 microRNA; biological markers; carcinoma; human; kidney; renal cell