Cancer Res Treat.  2003 Dec;35(6):478-482.

Telomerase Activity in Gastric Adenocarcinomas: Frozen Tissues Versus Methacarn-fixed Paraffin-embedded Tissues

• Yoo J
• Kang SJ
• Kang CS

Abstract

PURPOSE
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. MATERIALS AND 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). CONCLUSION: 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.

Keyword

Telomerase; Methacarn-fixation; Stomach neoplasm

MeSH Terms

Adenocarcinoma*
Carcinogenesis
DNA
DNA Replication
Enzyme-Linked Immunosorbent Assay
Humans
Paraffin
RNA-Directed DNA Polymerase
Stomach Neoplasms
Telomerase*
DNA
Paraffin
RNA-Directed DNA Polymerase
Telomerase