title: Tumor suppressor miRNA-204-5p promotes apoptosis by targeting BCL2 in prostate cancer cells.
abstract: BACKGROUND
  Prostate cancer (PCa) is a leading cause of cancer-related death in men, which emphasizes the need for novel therapeutic approaches. Targeting microRNA (miRNA) has been considered as a therapeutic strategy against cancers. Human miR-204-5p potentially targeting BCL2 has been reported to be downregulated in various cancers. We hypothesized that miR-204-5p overexpression induces cancer cell apoptosis by repressing BCL2 expression.
  
  
  METHODS
  A vector harboring mature miR-204-5p was constructed and delivered into human PCa cells. The expression level of miR-204-5p was determined by miRNA quantitative polymerase chain reaction (QPCR). Luciferase reporter assays were performed to verify the function of mature miR-204-5p and its direct binding to BCL2 transcripts. The expression levels of BCL-2 messenger RNA (mRNA) and protein samples were measured by QPCR and Western blot, respectively. Cell viability was detected by WST-1 assays. Induction of apoptosis was determined by increased levels of cleavage caspase 3 and caspase 3/7 activity.
  
  
  RESULTS
  The expression levels of miR-204-5p were downregulated in PCa cells compared with normal prostate epithelial cells. Transfection of pSM-204 resulted in up to 6.2-fold higher expression of miR-204-5p when compared with pSM control. The mRNA levels of several potential target genes of miR-204-5p were decreased in pSM-204-transfected PC3 and Rv1 cells. BCL2 mRNA and protein expression decreased in miR-204-5p-transfected cells, which led to cytochrome C release from mitochondria. It subsequently increased cleaved caspase 3 and caspase 3/7 activities and reduced cell viability. Cotransfection of a reporter vector harboring the BCL2 3'-untranslated region to compete with endogenous transcripts partially rescued miR-204-5p-induced apoptosis.
  
  
  CONCLUSIONS
  Human miR-204-5p targets BCL2 in PCa cells. Restoration of miR-204-5p in PCa could therefore be considered as a novel strategy by targeting antiapoptotic BCL2.
authors: Department of Urology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan.
authors: Yi-Chia
authors: YC
authors: Lin
authors: Central Laboratory, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors: Ji-Fan
authors: JF
authors: Lin
authors: Department of Urology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan.
authors: Te-Fu
authors: TF
authors: Tsai
authors: Department of Urology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan.
authors: Kuang-Yu
authors: KY
authors: Chou
authors: Department of Urology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors: Hung-En
authors: HE
authors: Chen
authors: Department of Urology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan; School of Medicine, Fu-Jen Catholic University, New Taipei City, Taiwan; School of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: M001009@ms.skh.org.tw.
authors: Thomas I-Sheng
authors: TI
authors: Hwang
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D015854:Up-Regulation
chemical_list: C000595707:BCL2 protein, human; C549404:MIRN204 microRNA, human; D035683:MicroRNAs; D019253:Proto-Oncogene Proteins c-bcl-2
keywords: BCL2; apoptosis; microRNAs; prostate cancer