抄録
We improved the in situ hybridization method using biotinylatyed probes for the detection of human papillomavirus (HPV) 16 and 18 DNA in formalin-fixed and paraffin-embedded tissue sections. Our method included HCl treatment, digestion with 30μg/ml proteinase K, post-fixation with 70% ethanol and incubation with a streptavidin-biotinylated alkaline phosphatase conjugate for visualization of biotin molecules on DNA probes. The sensitivity of this method using biotinylated DNA probes was comparable to using 35S labeled RNA probes. Using this method, 72 cases of cervical dysplasia and 51 cases of squamous cell carcinoma of cervix were examined for the presence of HPV 16 and 18 DNA. HPV 16 DNA was detected by in situ hybridization in 19 (26%) cases: 8 of 17 (47%) with mild dysplasia, 4 of 24 (16%) with moderate dysplasia and 7 of 30 (23%) with severe dysplasia. In 25 cases of carcinoma in situ and 26 cases of invasive carcinoma, HPV 16 or 18 DNA was detected in 8 cases of which 4 cases had an associated nonmalignant lesion. All four cases showed that the intensity in the malignant lesions was less than the dysplasia or benign lesions in the same patients. These findings suggest that replication of HPV DNA might be suppressed in the transformed cells.
