title: Dysregulation of MicroRNA-196b-5p and MicroRNA-375 in Gastric Cancer.
abstract: OBJECTIVE
  Dysregulated microRNAs (miRNAs) can contribute to cancer development by leading to abnormal proliferation of cells, apoptosis, and differentiation. Although several miRNAs that are related to gastric cancer have been identified, the reported results have been inconsistent. The aim of this study was to determine miRNA expression profiles and validate miRNAs up- and down-regulated in gastric cancer.
  
  
  METHODS
  We evaluated 34 primary gastric cancer tissues and paired adjacent nontumorous gastric tissues. Total RNA was extracted, and low-molecular-weight RNAs (<200 nucleotides) were isolated for further analysis. Two pairs of tissues were processed for GeneChip microarray analysis, and the identified up- and down-regulated miRNAs were validated by real-time quantitative polymerase chain reaction (qPCR).
  
  
  RESULTS
  In the set of differentially expressed miRNAs, 5 were overexpressed by more than 2 fold, and 5 were reduced by 2 fold or less in gastric cancer tissues compared with normal gastric tissues. Four of these miRNAs (miR-196b-5p, miR-375, miR-483-5p, and miR-486-5p) were then validated by qPCR, and the relative expression levels of 2 miRNAs (miR-196b-5p and miR-375) were significantly different between cancer and normal tissues.
  
  
  CONCLUSIONS
  Our results revealed that the expression of miR-196b-5p and miR-375 significantly correlates with gastric cancer. These miRNAs could therefore serve as diagnostic biomarkers of gastric cancer.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Seung Woo
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Clinical Research Institute, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Ki Cheol
authors.initials: KC
authors.lastname: Park
authors.affiliation: Department of General Surgery, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Jeong Goo
authors.initials: JG
authors.lastname: Kim
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Moon
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Sang Bum
authors.initials: SB
authors.lastname: Kang
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Lee
authors.affiliation: Department of Pathology, Daejeon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Daejeon, Korea.
authors.forename: Hae Joung
authors.initials: HJ
authors.lastname: Sul
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Incheon St. Mary's Hospital, School of Medicine, The Catholic University of Korea, Incheon, Korea.
authors.forename: Jeong Seon
authors.initials: JS
authors.lastname: Ji
authors.affiliation: Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Hyun Yong
authors.initials: HY
authors.lastname: Jeong
keywords: MicroRNAs; Microarray analysis; Neoplasms; Polymerase chain reaction; Stomach