Telomerase activity, MIB-1, PCNA, HPV 16 and p53 as diagnostic markers for cervical intraepithelial neoplasia

The present investigation evaluated the relationship between dysplasia of the uterine cervix and telomerase activity, expression of p53, MIB-1 and PCNA. Telomerase activity was measured on cervical cytobrush material from 126 women suspected of having dysplasia and 61 controls using the telomeric repeat amplification protocol. Immunohistochemistry was used to detect the tumor suppressor protein p53 and cell proliferation, the latter by MIB-1 and PCNA expression. Infection with human papillomavirus 16 was detected by PCR amplification and Southern blot hybridization of DNA extracted from the same brush material. Positive telomerase activity was found in 5 of 43 (11.6%) normal samples, 12 of 57 (21.1%) samples with inflammation or koilocytosis, 7 of 17 (41.2%) CIN 1 (cervical intraepithelial neoplasia, grade 1), 8 of 20 (40.0%) CIN 2, and 25 of 42 (59.5%) CIN 3/ CIS. Telomerase activity was significantly related to the level of dysplasia (p <0.001) and proliferation measured by MIB-1 (p=0.019), but not to the level of PCNA (p=0.445), HPV 16 status (p=0.098) or staining for p53 (p=0.271). Dysplasia was also related to PCNA, MIB1, p53, and presence of HPV 16. A sequential increase in the examined parameters, paralleling the progression of abnormality, was observed. PCNA and telomerase showed an increase in CIN 1, MIB-1 and HPV16 in CIN 2, and finally p53 in CIN 3/CIS.