title: Underexpression of miR-126 and miR-20b in hereditary and nonhereditary colorectal tumors.
abstract: OBJECTIVE
  The aim of the study was to determine the significance of miR-126 and miR-20b in colorectal carcinogenesis.
  
  
  METHODS
  We analyzed the expressions of miR-126 and miR-20b in 136 colorectal tumors from 39 microsatellite stable (MSS) tumors, 23 high microsatellite instability (MSI-H) tumors, 16 Lynch syndrome, and 58 familial adenomatous polyposis (FAP) tumors including adenoma, intramucosal carcinoma, and invasive carcinoma.
  
  
  RESULTS
  All four kinds of tumors showed underexpression of both miR-126 and miR-20b. The frequency of miR-126 downregulation was 100.0% in FAP adenomas, 85.7% in FAP intramucosal carcinomas, 78.9% in invasive carcinomas, 81.3% in Lynch syndrome tumors, 68.4% in MSS tumors, and 65.4% in MSI-H tumors. The frequency of miR-20b downregulation was 64.0% in FAP adenomas, 50.0% in FAP intramucosal carcinomas, 73.3% in invasive carcinomas, 62.5% in Lynch syndrome tumors, 79.5% in MSS tumors, and 91.3% in MSI-H tumors. The current study demonstrated underexpression of miR-126 and miR-20b in various types of colorectal cancer. These findings support the hypothesis that angiogenesis results from underexpressions of miR-126 and miR-20b and occurs as an early event in colorectal carcinogenesis.
  
  
  CONCLUSIONS
  Underexpression of miR-126 and miR-20b was observed in various types of colorectal cancer, and occurs as an early event of colorectal carcinogenesis in FAP tumors.
authors.affiliation: Department of Surgery, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital, Tokyo, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Takeru
authors.initials: T
authors.lastname: Iijima
authors.forename: Rika
authors.initials: R
authors.lastname: Wakaume
authors.forename: Keiichi
authors.initials: K
authors.lastname: Takahashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nakano
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Nakayama
authors.forename: Takeo
authors.initials: T
authors.lastname: Mori
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Horiguchi
authors.forename: Michiko
authors.initials: M
authors.lastname: Miyaki
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000378:metabolism*; D011125:Adenomatous Polyposis Coli / Q000235:genetics / Q000378:metabolism*; D063646:Carcinogenesis / Q000235:genetics / Q000378:metabolism; D002277:Carcinoma / Q000235:genetics / Q000378:metabolism*; D003123:Colorectal Neoplasms, Hereditary Nonpolyposis / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D053842:Microsatellite Instability
chemical_list: C527111:MIRN126 microRNA, human; C534451:MIRN20a microRNA, human; D035683:MicroRNAs