title: miR-21 downregulated TCF21 to inhibit KISS1 in renal cancer.
abstract: OBJECTIVE
  To investigate whether the microRNA-21 gene (miR-21) could regulate renal cancer cells invasion by downregulation of TFC21 and KISS1.
  
  
  METHODS
  Quantitative real-time polymerase chain reaction was applied to evaluate the expression level of miRNA-21 in renal cancer and normal renal cell samples. The regulated effects of miR-21 to TCF21 were detected by Western blot after pre/anti-miR-21 was transfected to Caki-1 cells. The luciferase activity assay was used to reveal the predicted target gene of miR-21 was direct and specific. Small interfering RNA-TCF21 was transfected to Caki-1 cells to inhibit the expression of the TCF21 gene. Next, the expression of the KISS1 gene was detected by Western blot in Caki-1 cells with TCF21 gene silencing. The expression vector, pcDNA3.1-KISS1, was transfected to Caki-1 cells to upregulate the expression of the KISS1 gene. The invasion ability of Caki-1 cells with KISS1 overexpression was analyzed using the Transwell assay.
  
  
  RESULTS
  Our study showed that miR-21 was upregulated in human renal cell carcinoma specimens compared with its expression in normal renal cell specimens. Pre-miR-21 could upregulate the expression of miR-21 and downregulate the expression of TCF21, and anti-miR-21 showed the opposite effects. siRNA-TCF21 decreased the expression of the TCF21 protein, and the expression of KISS1 was downregulated in Caki-1 cells with TCF21 gene silencing. pcDNA3.1-KISS1 transfection upregulated the expression of the KISS1 protein, and the invasion ability of Caki-1 cells with KISS1 overexpression decreased markedly.
  
  
  CONCLUSIONS
  Aberrantly expressed miR-21 might regulate the TCF21-KISS1-associated renal cell carcinoma cell invasion pathway, and this miRNA signature could offer a novel potential therapeutic strategy for renal cell carcinoma.
authors.affiliation: Department of Urinary Surgery, Affiliated Shengjing Hospital, China Medical University, Shenyang, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Guo
authors.forename: Chao
authors.initials: C
authors.lastname: Shang
authors.forename: YongSheng
authors.initials: Y
authors.lastname: Song
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
mesh_terms: D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism*; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D015536:Down-Regulation / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D020868:Gene Silencing / Q000502:physiology; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D059648:Kisspeptins / Q000502:physiology*; D035683:MicroRNAs / Q000502:physiology*; D009361:Neoplasm Invasiveness; D014162:Transfection; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000502:physiology
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D059648:Kisspeptins; D035683:MicroRNAs; C106628:KISS1 protein, human; C524940:MIRN21 microRNA, human; C491825:TCF21 protein, human