Telomerase Activity in Oral Leukoplakia Tissues / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Telomeres are specialized structures found at the ends of eukaryotic chromosomes. Telomeres stabilize the chromosome and protect DNA from illegitimate recombination. Telomerase is a ribonucleoprotein, a RNA dependent DNA polymerase, and acts as a reverse transcriptase-like enzyme, which maintains telomere length by adding telomeric repeat units of TTAGGG to the telomeric end. These telomeric repeat units have been found only in cells with unlimited replicative potential such as sperm cells, immortalized cell lines and cancer tissues, but not in normal somatic cells. Telomerase is believed to be characteristic of and may be the best indicator of cell immortality. This study was performed to indentify the role of telomerase activity in the multistep carcinogenesis of oral squamous cell carcinoma. MATERIALS AND METHODS:We performed a telomeric repeat amplification protocol assay in 10 oral leukoplakia, 5 tongue cancers and 10 normal oral mucosa tissues. RESULTS: All the five tongue cancer tissues showed telomerase activity. Although telomerase activity was detected in 9 of 10 oral leukoplakia tissues and in 9 of 10 normal oral mucosa tissues, the activity of telomerase was low compared to that of cancer tissues by semiquantitative analysis. CONCLUSION: These findings suggest that telomerase maybe play a key role in multistep carcinogenesis of oral malignancy. Telomerase activity was detectable in normal oral mucosa with renewal activity suggested that this enzyme might be an indicator of cell proliferation.