Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new type-specific, sensitive, non-radioactive assay is described for the detection of human papillomavirus (HPV) DNA in tissues. Sequences within the E6 gene were amplified by the polymerase chain reaction (PCR), using primer pairs which clearly distinguish HPV types, including those with close sequence homology such as 6b and 11. The amplified DNA products were identified by non-radioactive oligonucleotide hybridization and restriction endonuclease mapping, and the method was sufficiently sensitive to detect between 3 and 5 SiHa cells (each containing 1-2 copies of HPV 16 DNA) amongst 10,000 non-HPV-containing cells. Frozen and archival paraffin sections were equally acceptable substrates for the reaction. The assay was applied to frozen sections of full thickness cervical epithelium from 60 cases of cervical intraepithelial neoplasia (CIN) and 24 normal cervical controls. HPV DNA was detected in 60 per cent of cases of CIN 3 and CIN 2, in 25 per cent of cases of CIN 1, and in none of the normal controls. Prevalence of HPV 16 was similar (approximately 50 per cent) in both CIN 2 and CIN 3, and in the whole series HPV 16 was almost five-fold more common than HPV 18. Low-risk HPV types were present in 5 per cent of CIN 1, but 0 per cent of CIN 2 and CIN 3 biopsies. The data emphasize the biological similarity of CIN 2 and CIN 3 lesions, and their divergence from CIN 1.
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PMID:HPV in full thickness cervical biopsies: high prevalence in CIN 2 and CIN 3 detected by a sensitive PCR method. 166 60

The diagnosis of cervical intraepithelial neoplasia (CIN) has low interobserver reproducibility. The pathogenesis of human papillomavirus (HPV) from infection to high-grade CIN is well understood. In benign lesions, HPV-DNA is often packaged into virions, whereas malignant transformation disrupts virion assembly. It is conceivable that if cervical lesions were exposed to endonuclease digestion, HPV virions would alter nuclear susceptibility to DNA degradation. We propose that susceptibility to endonuclease digestion can serve as a simple marker to identify CIN grade. From paraffin-embedded tissue blocks, condyloma accuminata, CIN I-III, and cervical carcinoma cases were identified. Sections were placed in a bath containing DNAse I for DNA digestion. Residual DNA was stained by a Feulgen process. Endonuclease-resistant DNA (erDNA) staining was correlated to disease grade. In addition, 10 HPV (+) patients whose infection regressed and 8 whose infection progressed to CIN II or above had their initial HPV lesions stained for erDNA. erDNA was observed in 81% condylomas and 80% CIN I cases. All CIN II, III, and cancer cases were endonuclease sensitive with 100% of lesions showing no staining. Eighty percent of HPV lesions that regressed had erDNA staining, whereas 75% lesions that progressed had no erDNA staining. The spectrum of cervical disease caused by HPV has different susceptibilities to endonuclease digestion, which may aid in the diagnosis of CIN. Furthermore, in our small pilot study, erDNA status was associated with the clinical outcomes. Prospective studies are needed to confirm this observation. erDNA status is a promising novel biomarker.
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PMID:Endonuclease-resistant DNA: a novel histochemical marker for cervical intraepithelial neoplasia and cervical carcinoma. 2212 17