title: Expression profile of microrna-145 in urothelial bladder cancer.
abstract: OBJECTIVE
  Bladder cancer (BC) is the second most common malignancy of the urinary tract, with high mortality. The knowledge of the molecular pathways associated with BC carcinogenesis is crucial to identify new diagnostic and prognostic biomarkers. MicroRNAs (miRNAs) are short non-coding RNA molecules that play important roles in the regulation of gene expression by acting directly on mRNAs. miR-145 has been considered as a tumor suppressor, which targets the c-MYC, MUC-1 and FSCN1 genes. Our aim was to evaluate the expression profile of miR-145 in low-grade non-invasive and high-grade invasive bladder urothelial carcinomas.
  
  
  METHODS
  We studied 30 specimens of low-grade, non-invasive pTa and 30 of pT2/pT3 high-grade invasive UC obtained by transurethral resection or radical cystectomy, followed over a mean time of 16.1 months. Normal controls were represented by five samples of normal bladder biopsy from patients who underwent retropubic prostatectomy to treat BPH. miRNA extraction and cDNA generation were performed using commercial kits. Analysis was performed by qRT-PCR, and miR-145 expression was calculated using the 2-(▵▵ct) method; we used RNU-43 and RNU-48 as endogenous controls.
  
  
  RESULTS
  miR-145 was under-expressed in 73.3% and 86.7% of pTa and pT2/pT3, respectively, with expression means of 1.61 for the former and 0.66 for the last. There were no significant differences in miR-145 expression and histological grade, tumor stage, angiolymphatic neoplastic invasion and tumor recurrence.
  
  
  CONCLUSIONS
  miR-145 is under-expressed in low-grade, non-invasive and high-grade invasive urothelial bladder carcinoma and may play an important role in the carcinogenesis pathway, being an interesting candidate diagnostic marker.
authors.affiliation: Laboratory of Medical Investigation, Urology Department - LIM55, University of São Paulo Medical School, São Paulo, Brazil. nelson.dip@hotmail.com
authors.forename: Nelson
authors.initials: N
authors.lastname: Dip
authors.forename: Sabrina T
authors.initials: ST
authors.lastname: Reis
authors.forename: Miguel
authors.initials: M
authors.lastname: Srougi
authors.forename: Marcos F
authors.initials: MF
authors.lastname: Dall'Oglio
authors.forename: Katia R M
authors.initials: KR
authors.lastname: Leite
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D014408:Biomarkers, Tumor / Q000032:analysis; D002273:Carcinogens / Q000378:metabolism; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000032:analysis*; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local; D018709:Statistics, Nonparametric; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D002273:Carcinogens; C541010:MIRN145 microRNA, human; D035683:MicroRNAs