title: Both cancerous miR-21 and stromal miR-21 in urothelial carcinoma are related to tumour progression.
abstract: OBJECTIVE
  Urothelial carcinoma (UC) is a globally common cancer. miR-21 appears to be important in the tumorigenesis of almost all types of human cancer. However, its precise localization and significance in UC have yet to be clarified. The aim of this study was to examine miR-21 expression in UC and reveal its clinicopathological importance.
  
  
  RESULTS
  Tissue arrays of 232 UCs were examined for miR-21 by the use of in-situ hybridization. One hundred and forty-eight transurethral resection specimens and 84 surgically resected specimens were used. After miR-21 positivity had been evaluated separately in tumour cells and the tumour stroma, it was compared with clinicopathological factors and overall survival. miR-21 was strongly expressed in tumour cells in 9% of cases and in the tumour stroma in 6% of cases. Stromal miR-21 positivity was lower than that of cancerous miR-21. Both miR-21s were correlated with each other and related to tumour stage, locus, and histological grade. In addition, strong positivity of miR-21 in cancer and the stroma was significantly related to poorer prognosis among surgically resected cases. In a Cox proportional hazard model, cancerous miR-21 was the only independent prognostic factor except for tumour stage.
  
  
  CONCLUSIONS
  miR-21 in both cancer and stromal cells is closely related to tumour progression in UC. miR-21 may be a prognostic marker for cancer progression.
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Rena
authors.initials: R
authors.lastname: Ohno
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Uozaki
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Kikuchi
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Arisa
authors.initials: A
authors.lastname: Kumagai
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Aso
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Shiori
authors.initials: S
authors.lastname: Watabe
authors.affiliation: Department of Urology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Muto
authors.affiliation: Department of Urology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Raizo
authors.initials: R
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D002295:Carcinoma, Transitional Cell / Q000235:genetics / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis*; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D017154:Stromal Cells / Q000378:metabolism; D046888:Tissue Array Analysis; D059016:Tumor Microenvironment / Q000502:physiology*; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; C524940:MIRN21 microRNA, human; D035683:MicroRNAs
keywords: in-situ hybridization; miR-21; progression; survival; tumour stroma; urothelial carcinoma