Normal and Tumour Tissue mRNA Expressions of Telomerase Complex Genes in Several Types of Cancer

Abstract

Aims: To investigate the changes in mRNA expression levels of telomerase-related significant proteins in several types of cancer. Methods: Human telomerase reverse transcriptase, pontin, reptin and dyskerin expressions were measured in normal and tumour tissues obtained from 26 patients with colorectal, breast and gastric cancers, using the realtime reverse transcriptase-polymerase chain reaction method. Results: For all patients, no significant difference was found in mRNA expressions of human telomerase reverse transcriptase and dyskerin (p>0.05), although their levels in tumour tissues were found to be higher than in normal tissues. However, pontin and reptin mRNA expressions were significantly higher in tumour tissues than in normal tissues (p<0.01). While human telomerase reverse transcriptase showed a high correlation with only pontin (p<0.001) in normal tissues, high positive correlations were observed between human telomerase reverse transcriptase with pontin (p<0.005), reptin (p<0.01) and dyskerin (p<0.01) in tumour tissues. Conclusion: The increased mRNA expressions of all four genes in tumour tissues may suggest a role in cancer development. Correlations of pontin, reptin and dyskerin with human telomerase reverse transcriptase support the hypotheses describing their roles in telomerase complexes

Keywords

• Human telomerase reverse transcriptase, pontin, reptin, dyskerin, telomerase, cancer

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