OBJECTIVE: Telomerase is an RNA-dependent DNA polymerase that synthesizes TTAGGG telomeric DNA. It has been detected in a variety of human malignancies, suggesting that it's activity may play a role in the tumorigenic process. Also, maintenance of telomerase activity is associated with increased resistance to apoptosis. Caspase-3 activation has been found to be essential components of the apoptotic pathway. METHODS: To determine whether telomerase is involved in carcinogenesis of uterine cervix and to analyze the relationship between telomerase RNA and caspase-3 expression according to cervical cancer stage, we performed in situ hybridization for telomerase RNA and immunohistochemistry for caspase-3. The materials were 10 normal cervical tissues, 12 low grade intraepithelial lesions (LSIL), 20 high grade intraepithelial lesions (HSIL), 17 microinvasive carcinomas, 19 invasive carcinomas. RESULTS: Telomerase RNA was weakly expressed in a few basal cells of normal squamous epithelium in uterine cervix. But, high expression rate was noted in squamous intraepithelial lesions and invasive carcinoma groups. Expression of telomerase RNA was demonstrated 5 (41.6%) of LSIL, 7 (35.0%) of HSIL, 6 (35.2%) of microinvasive carcinoma, and 11 (57.8%) of invasive carcinoma. Expression of caspase-3 was demonstrated 0% of LSIL, 13 (65.0%) of HSIL, 13 (76.4%) of microinvasive carcinoma, and 7 (36.8%) of invasive carcinoma. Relationship between telomerase RNA and caspase-3 expression according to stage was not seen. Telomerase RNA and caspase-3 expression showed weakly inverse correlation in invasive carcinoma group. Telomerase RNA and caspase-3 expression was not correlated with clinico-pathologic factors, including stage, tumor differentiation, invasion depth, and lymph node metastasis (p>0.05). But, weak correlation between telomerase RNA expression and tumor size was noted (p=0.05). CONCLUSION: These data indicate telomerase might be involved in carcinogenesis of uterine cervix. Distinct relationship between telomerase RNA and caspase-3 was not seen according to stage. Expression of telomerase RNA and caspase-3 had no correlation with clinico-pathologic factors.