title: Tumor suppressive microRNA-1285 regulates novel molecular targets: aberrant expression and functional significance in renal cell carcinoma.
abstract: MicroRNAs (miRNA) are non-coding RNAs, approximately 22 nucleotides in length, which function as post-transcriptional regulators.  A large body of evidence indicates that miRNAs regulate the expression of cancer-related genes involved in proliferation, migration, invasion, and metastasis. The aim of this study was to identify novel cancer networks in renal cell carcinoma (RCC) based on miRNA expression signatures obtained from RCC clinical specimens. Expression signatures revealed that 103 miRNAs were significantly downregulated (more than 0.5-fold change) in RCC specimens. Functional screening (cell proliferation assays) was performed to identify tumor suppressive activities of 20 downregulated miRNAs. Restoration of mature miRNAs in cancer cells showed that 14 miRNAs (miR-1285, miR-206, miR-1, miR-135a, miR-429, miR-200c, miR-1291, miR-133b, miR-508-3p, miR-360-3p, miR-509-5p, miR-218, miR-335, miR-1255b and miR-1285) markedly inhibited cancer cell proliferation, suggesting that these miRNAs were candidate tumor suppressive miRNAs in RCC. We focused on miR-1285 because it significantly inhibited cancer cell proliferation, invasion, and migration following its transfection. We addressed miR-1285-regulated cancer networks by using genome-wide gene expression analysis and bioinformatics. The data showed that transglutaminase 2 (TGM2) was directly regulated by miR-1285. Silencing of the target gene demonstrated significant inhibition of cell proliferation and invasion in the RCC cells. Furthermore, immunohistochemistry showed that TGM2 expression levels in RCC specimens were significantly higher than those in normal renal tissues. Downregulation of tumor suppressive miR-1285, which targets oncogenic genes including TGM2, might contribute to RCC development. Thus, miR-1285 modulates a novel molecular target and provides new insights into potential mechanisms of RCC oncogenesis.
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Hiedo
authors.initials: H
authors.lastname: Hidaka
authors.forename: Naohiko
authors.initials: N
authors.lastname: Seki
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yoshino
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamasaki
authors.forename: Yasutoshi
authors.initials: Y
authors.lastname: Yamada
authors.forename: Nijiro
authors.initials: N
authors.lastname: Nohata
authors.forename: Miki
authors.initials: M
authors.lastname: Fuse
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakagawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Enokida
mesh_terms: D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D052138:Genes, Neoplasm / Q000235:genetics*; D016147:Genes, Tumor Suppressor / Q000502:physiology; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics* / Q000473:pathology; D035683:MicroRNAs / Q000235:genetics / Q000502:physiology*; D046228:Microarray Analysis; D009361:Neoplasm Invasiveness; D046888:Tissue Array Analysis
chemical_list: C572554:MIRN1285 microRNA, human; D035683:MicroRNAs