[Telomerase activity in gastrointestinal, bladder and breast carcinomas and their clinical applications].

Telomere ends are known to be shortened at every division of the cells. Telomerase is a ribonucleoprotein which compensate for the telomere ends and indispensable for the immortalization of the cells. It is reported that the enzyme is activated in a variety of cancer cells. In the present report, the enzyme was activated in more than 70% of gastrointestinal, bladder and breast cancer by TRAP assay. Moreover, in order to elucidate whether the enzyme activity is useful for the non-invasive detection of exfoliated cancer cells in the colon bowel washings, urine and fine needle aspirate of the breast tumors, TRAP assay was performed. In most of the cases, the positive findings were observed which support that the enzyme activity is useful for the clinical application. The expression of mRNA and protein for hTERT was detected in cancer cells, however, the assay contains the pitfall including the Taq inhibitor or telomerase inhibitor. Moreover, the activity is also detected although it is weak, in the benign or premalignant lesions. Further analysis is required for the clinical application of the method.