title: Down-regulation of TRF1, TRF2 and TIN2 genes is important to maintain telomeric DNA for gastric cancers.
abstract: BACKGROUND
  The maintenance of telomeres may be required for long-term proliferation of tumors. Activity of telomerase, a ribonucleoprotein complex that elongates telomeres, has been found in almost all human tumors but not in adjacent normal cells. Several factors which regulate telomere length, TRF1 and 2, TIN2, tankyrase and Rap1, have been identified. TRF1, TRF2 and TIN2 are negative regulators of telomere length, while tankyrase and Rap1 act as positive regulators. In this study, we quantitated the mRNA of these five genes in gastric cancers to clarify the mechanism by which cancer cells maintain telomere length.
  
  
  METHODS
  The expression of these five genes transcription was determined using a quantitative RT-PCR.
  
  
  RESULTS
  TRF1, TRF2 and TIN2 mRNAs were significantly down-regulated in cancers compared to non-cancerous mucosa. Neither tankyrase nor Rap1 was upregulated in cancers.
  
  
  CONCLUSIONS
  Down-regulation of TRF1, TRF2 and TIN2 gene expression may be important to maintain telomeres in gastric cancer.
authors.affiliation: Department of Laboratory Diagnosis, and Clinical Laboratory Medicine, Sapporo Medical University, School of Medicine, South-1, West-16, Chuo-ku, Sapporo, 060-8543, Japan.
authors.forename: Mikako
authors.initials: M
authors.lastname: Yamada
authors.forename: Naoki
authors.initials: N
authors.lastname: Tsuji
authors.forename: Masashi
authors.initials: M
authors.lastname: Nakamura
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Moriai
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kobayashi
authors.forename: Atsuhito
authors.initials: A
authors.lastname: Yagihashi
authors.forename: Naoki
authors.initials: N
authors.lastname: Watanabe
mesh_terms: D004273:DNA, Neoplasm / Q000235:genetics* / Q000378:metabolism; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D000089804:Shelterin Complex; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism; D038501:Tankyrases / Q000096:biosynthesis / Q000235:genetics; D016615:Telomere / Q000235:genetics* / Q000378:metabolism; D034501:Telomere-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D035321:Telomeric Repeat Binding Protein 1 / Q000096:biosynthesis / Q000235:genetics*; D035341:Telomeric Repeat Binding Protein 2 / Q000096:biosynthesis / Q000235:genetics*; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D012333:RNA, Messenger; D000089804:Shelterin Complex; D038501:Tankyrases; D034501:Telomere-Binding Proteins; D035321:Telomeric Repeat Binding Protein 1; D035341:Telomeric Repeat Binding Protein 2; C440809:TERF2IP protein, human; C440868:TINF2 protein, human; C418109:TNKS protein, human