title: MicroRNAs as potential target gene in cancer gene therapy of gastrointestinal tumors.
abstract: BACKGROUND
  MicroRNA (miRNA) is a small non-coding RNA, which negatively regulates the expression of many target genes, thereby contributing to the modulation of diverse cell fates. Recent advances in molecular biology have revealed the potential role of miRNAs in tumor initiation, progression and metastasis. Aberrant regulation of miRNAs has been frequently reported in a variety of cancers, including gastrointestinal tumors, suggesting that cancer-related miRNAs are promising as novel biomarkers for tumor diagnosis and are potential target genes for cancer gene therapy against gastrointestinal tumors.
  
  
  METHODS
  The review focuses on the role of specific miRNAs (miR-192/194/215 and miR-7) in the differentiation of gastrointestinal epithelium and on the role of tumor-suppressive (miR-34, miR-143, miR-145) and oncogenic miRNAs (miR-21, miR-17-92 cluster) in gastrointestinal tumors. Furthermore, the potential role of miRNAs as novel biomarkers and target genes for cancer gene therapy against gastrointestinal tumors are discussed. We will also outline the potential clinical application of miRNAs for tumor diagnosis and cancer gene therapy against gastrointestinal tumors.
  
  
  CONCLUSIONS
  Exploration of tumor-related miRNAs would provide important opportunities for the development of novel cancer gene therapies aimed at normalizing the critical miRNAs that are deregulated in gastrointestinal tumors.
authors.affiliation: Okayama University Hospital, Center for Gene and Cell Therapy, Okayama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tazawa
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kagawa
authors.forename: Toshiyoshi
authors.initials: T
authors.lastname: Fujiwara
mesh_terms: D000818:Animals; D005770:Gastrointestinal Neoplasms / Q000235:genetics / Q000628:therapy*; D015316:Genetic Therapy; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*
chemical_list: D035683:MicroRNAs