title: Telomere length and human telomerase reverse transcriptase expression as markers for progression and prognosis of colorectal carcinoma.
abstract: OBJECTIVE
  Maintenance of telomeres through reactivation of telomerase is a prerequisite for tumors to preserve their ability to proliferate. The purpose of this study was to evaluate telomere length and human telomerase reverse transcriptase (hTERT) expression as markers for progression and prognosis of colorectal carcinoma.
  
  
  METHODS
  Telomere length and hTERT expression were analyzed in matched cancer and adjacent noncancer mucosa samples from 57 patients with R0-resected colorectal carcinoma. The median follow-up time was 76 months.
  
  
  RESULTS
  Telomere length and hTERT expression correlated significantly in cancer tissues and adjacent mucosa samples (r = 0.52, P <.001; and r = 0.54, P <.001, respectively). Overall, cancer tissue had shorter telomeres than adjacent mucosa (P <.001). Only in noncancer tissue did telomere length decrease with age (r = 0.36; P <.01). Telomere length in cancer tissue was significantly correlated with tumor stage (P <.01), with longer telomeres in advanced tumors. Patients with ratios of telomere length in cancer to noncancer tissue greater than 0.90 had a significantly poorer overall survival compared with patients with smaller telomere length ratios (P <.002). In multivariate analysis, the telomere length ratio proved to be of independent prognostic value (P <.03).
  
  
  CONCLUSIONS
  Telomeres in colorectal carcinoma tissue were significantly shorter compared with adjacent normal mucosa as an indication for extensive cell proliferation. The correlation with tumor stage and patient survival suggest that hTERT-mediated telomere stabilization may be critical for progression and prognosis of colorectal carcinoma.
authors.affiliation: Chirurgische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität München, Munich, Germany. gertler@nt1.chir.med.tu-muenchen.de
authors.forename: Ralf
authors.initials: R
authors.lastname: Gertler
authors.forename: Robert
authors.initials: R
authors.lastname: Rosenberg
authors.forename: Dominik
authors.initials: D
authors.lastname: Stricker
authors.forename: Jan
authors.initials: J
authors.lastname: Friederichs
authors.forename: Axel
authors.initials: A
authors.lastname: Hoos
authors.forename: Martin
authors.initials: M
authors.lastname: Werner
authors.forename: Kurt
authors.initials: K
authors.lastname: Ulm
authors.forename: Bernhard
authors.initials: B
authors.lastname: Holzmann
authors.forename: Hjalmar
authors.initials: H
authors.lastname: Nekarda
authors.forename: Joerg-Ruediger
authors.initials: JR
authors.lastname: Siewert
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics; D015139:Blotting, Southern; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D004268:DNA-Binding Proteins; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D005858:Germany; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012333:RNA, Messenger / Q000032:analysis; D016019:Survival Analysis; D019098:Telomerase / Q000096:biosynthesis* / Q000235:genetics; D016615:Telomere / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D019098:Telomerase