Expression of Human Telomerase RNA Is an Early Event of Stomach Carcinogenesis

• Published in: Cancer science Vol. 88; no. 2; pp. 103 - 107
• Main Authors: Kuniyasu, Hiroki, Domen, Tamiko, Hamamoto, Takahiro, Yokozaki, Hiroshi, Yasui, Wataru, Tahara, Hidetoshi, Tahara, Eiichi
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.02.1997; Japanese Cancer Association; John Wiley & Sons, Inc
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Carcinogenesis; Enzyme Activation; Female; Gastric cancer; Gastroenterology. Liver. Pancreas. Abdomen; Helicobacter Infections - enzymology; Helicobacter pylori; Human telomerase RNA; Humans; Intestinal metaplasia; Intestinal Mucosa - enzymology; Intestinal Mucosa - microbiology; Intestinal Mucosa - pathology; Intestine; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Metaplasia; Metaplasia - enzymology; Metaplasia - microbiology; Middle Aged; Mucosa; Precancerous Conditions - enzymology; Precancerous Conditions - microbiology; Rapid Communoication; Ribonucleic acid; RNA; RNA - metabolism; Stomach cancer; Stomach Neoplasms - enzymology; Stomach Neoplasms - microbiology; Telomerase; Telomerase - genetics; Telomerase - metabolism; Tumor cell lines; Tumor Cells, Cultured; Tumors; Human; Stomach; Carcinoma; RNA-directed DNA polymerase; Spirillales; Enzyme; Pathogenesis; Transferases; Spirillaceae; Malignant tumor; Gene expression; Carcinogenesis; Infection; Nucleotidyltransferases; Messenger RNA; Helicobacter pylori; Bacteriosis; Digestive diseases; Bacteria; Gastric disease
• ISSN: 0910-5050; 1347-9032; 1349-7006; 1876-4673
• DOI: 10.1111/j.1349-7006.1997.tb00353.x

Expression of human telomerase RNA (hTR) and telomerase activity in gastric cancer and corresponding non‐cancerous mucosa were studied. Telomerase activity was detected in 23 (88%) of 26 carcinoma tissues. Although all tumor specimens and non‐cancerous mucosa expressed various levels of hTR, 21 (81%) of 26 cases expressed hTR at a higher level in the tumor than that in the corresponding mucosa. All 8 gastric carcinoma cell lines also expressed hTR at high levels. Nine (35%) of 26 non‐cancerous mucosa showed telomerase activity and all of them contained intestinal metaplasia. The incidence of telomerase‐positive mucosa in grade 2 intestinal metaplasia was significantly higher than that in grade 0 or grade 1 intestinal metaplasia, whereas hTR overexpression was found in grade 0 or grade 1 intestinal metaplasia as well as grade 2 intestinal metaplasia. The degree of Heticobacter pylori infection increased in parallel with the level of hTR expression and telomerase positivity. These results overall suggest that Helicobacter pylori infection may he a strong trigger for hTR overexpression in intestinal metaplasia, and this may lead to telomerase reactivation.