title: The significance of telomerase activity in cancer lesions and the noncancerous epithelium of the esophagus.
abstract: BACKGROUND
  It is well known that telomerase activity is expressed in cancer cells. A recent study has revealed that weak telomerase activity was also detected in normal cells. Telomerase activity is thus thought to be useful as a diagnostic biomarker. In the present study, we studied the difference in telomerase activity between cancer tissue and noncancerous epithelium tissue of the esophagus.
  
  
  METHODS
  One hundred and thirty specimens of esophageal cancer tissue were collected at surgery and analyzed in a telomeric repeat amplification protocol (TRAP) assay. Telomerase was expressed quantitatively as the total product generated (TPG) value.
  
  
  RESULTS
  Telomerase activity was detected in all esophageal cancer tissues and in 87% of the noncancerous epithelium specimens. The mean TPG values in the cancer tissue and the noncancerous epithelium specimens were 49.5 +/- 39.5 (mean +/- 1 SD) and 11.5 +/- 5.9, respectively, with a significant difference (P < 0.0001).
  
  
  CONCLUSIONS
  The telomerase activity in esophageal cancers was significantly higher than that in the noncancerous epithelium. From the mean value plus 1 SD for noncancerous epithelium, the cutoff value was set at 17.4 as an esophageal cancer-specific diagnostic marker. This cutoff value showed a high predictive value, specificity, and sensitivity, of greater than 80% for each category. These results suggest that this cutoff value could be a useful biomarker for the detection of esophageal carcinoma.
authors.affiliation: Department of Surgery, Kurume University School of Medicine, 67 Asahi-machi, Kurume, Fukuoka 830-0011, Japan. kubota-f@f7.dion.ne.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kubota
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yamana
authors.forename: Susumu
authors.initials: S
authors.lastname: Sueyoshi
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Fujita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shirouzu
mesh_terms: D015415:Biomarkers; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000201:enzymology* / Q000473:pathology; D016022:Case-Control Studies; D004848:Epithelium / Q000201:enzymology; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000201:enzymology* / Q000473:pathology; D004947:Esophagus / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D019098:Telomerase / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D019098:Telomerase