title: Telomerase activity and telomere length in the colorectal polyp-carcinoma sequence.
abstract: OBJECTIVE
  The role of telomerase activity and telomere length in the adenoma-carcinoma sequence of colon carcinogenesis has not been well established. The objective of this study was to determine telomerase activity and telomere length patterns in patients with adenomatous polyps either associated or not with colorectal cancer, as well as the role of telomeric instability in the adenoma-carcinoma sequence.
  
  
  METHODS
  We included in the study 14 patients who underwent surgery for colorectal cancer and/or polyps. In 6 of these patients fresh samples of tumor tissue, polyps, and normal mucosa were obtained; in the 8 remaining cases, we collected only polyps and normal mucosa. We used the fluorescent-telomeric repeat amplification protocol assay (TRAP-F) to determine telomerase activity and telomere length using Southern-blot testing.
  
  
  RESULTS
  Telomerase activity was detected in 86% of polyps and 50% of associated normal mucosa. Mean telomerase activity in polyp tissue was 5.85; in the normal mucosa it was 0.58 TPG. Mean telomere length was 6.78 Kbp and 7.78, respectively. Polyps in patients without synchronous cancer had a telomerase activity that was significantly higher (9.4) than in those with cancer (1.1).
  
  
  CONCLUSIONS
  Telomerase activity increases in the colorectal adenoma-carcinoma sequence, concurrently with a decrease in telomere length. The presence of synchronous cancer modifies telomerase activity in polyps.
authors.affiliation: Department of Medicine, University of Lleida, Lleida, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Valls Bautista
authors.forename: C
authors.initials: C
authors.lastname: Piñol Felis
authors.forename: J M
authors.initials: JM
authors.lastname: Reñé Espinet
authors.forename: J
authors.initials: J
authors.lastname: Buenestado García
authors.forename: J
authors.initials: J
authors.lastname: Viñas Salas
mesh_terms: D003111:Colonic Polyps / Q000201:enzymology* / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000201:enzymology* / Q000235:genetics*; D018450:Disease Progression; D010865:Pilot Projects; D019098:Telomerase / Q000378:metabolism*; D016615:Telomere
chemical_list: D019098:Telomerase