title: Telomerase Activity in Gastric Adenocarcinomas: Frozen Tissues Versus Methacarn-fixed Paraffin-embedded Tissues.
abstract: OBJECTIVE
  Telomerase is an RNA-dependent DNA polymerase that synthesizes TTAGGG telomeric DNA onto chromosome ends to compensate for sequence loss during DNA replication. It has been detected in 85~90% of all primary human cancers, implicating that its apparent reactivation in tumors may play a role in the tumorigenic process. The purpose of this study was to evaluate telomerase activity in stomach cancer, and to determine whether methacarn-fixed paraffin-embedded tissues can replace frozen tissue sections for the telomerase (TRAP) assay.
  
  
  METHODS
  Frozen and corresponding methacarn-fixed paraffin-embedded tissue samples were obtained from 51 patients with gastric adenocarcinoma and analyzed for telomerase activity by using a TRAPeze ELISA kit.
  
  
  RESULTS
  Telomerase activity was detected in 37 (73%) frozen samples, and in 13 (25%) methacarn-fixed paraffin blocks. Telomerase activity was well correlated with depth of invasion (p=.037) and tumor differentiation (p=.022).
  
  
  CONCLUSIONS
  These data suggest that reactivated telomerase may play a significant role in the tumorigenesis of gastric cancer and may reflect the malignant potential of the tumor. It is noteworthy that methacarn- fixed tissue cannot as yet substitute for the frozen tissue in the TRAP assay.
authors.forename: Jinyoung
authors.initials: J
authors.lastname: Yoo
authors.forename: Seok Jin
authors.initials: SJ
authors.lastname: Kang
authors.forename: Chang Suk
authors.initials: CS
authors.lastname: Kang
keywords: Methacarn-fixation; Stomach neoplasm; Telomerase