Down-regulation of TRF1, TRF2 and TIN2 genes is important to maintain telomeric DNA for gastric cancers.
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.
Yamada
Mikako
M
Department of Laboratory Diagnosis, and Clinical Laboratory Medicine, Sapporo Medical University, School of Medicine, South-1, West-16, Chuo-ku, Sapporo, 060-8543, Japan.
Tsuji
Naoki
N
Nakamura
Masashi
M
Moriai
Ryosuke
R
Kobayashi
Daisuke
D
Yagihashi
Atsuhito
A
Watanabe
Naoki
N
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
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