Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:5.99.1.2 (topoisomerase)
 9,166 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of the catalytic subunit of telomerase protein (human telomerase reverse transcriptase [hTERT]), which is associated with telomerase activity, was evaluated as a potential marker of the high-grade premalignant cervical intraepithelial neoplasia (CIN 2/3) lesions. For comparison, cases of normal cervical squamous mucosa, low-grade CIN1 lesion, and cervical squamous cell carcinoma were included. The hTERT expression was also compared with Ki-67 and topoisomerase II-alpha (TPII-alpha) to determine the proliferative activity of the hTERT-positive dysplastic cells by a quantitative immunohistochemical staining method and was classified as follows: negative, 5% or less; moderate, 6% to 50%; or high, greater than 50% of the positive cells. The hTERT-positive cells were detected in a patchy pattern in the lower parabasal layers and in much of the basal layer in normal squamous mucosa. A similar frequency of Ki-67- or TPII-alpha-positive cells was observed, with the exception of the basal layer cells that were mostly negative. It is worthy to note that the recognizable intact basal layer cells in cases of CIN lesions were also consistently positive for the expression of hTERT, but rarely for Ki-67 or TPII-alpha. The expression of hTERT was detected in a less patchy pattern at a high or moderate percentage of the dysplastic epithelial cells each in 28.5% of cases of CIN1 lesions. A similar frequency, high and moderate percentage combined, of the TPII-alpha-positive dysplastic cell was also observed. In contrast, a high percentage of the hTERT-positive dysplastic cells were detected as diffuse basal or full-length thickness in 87.5% or 95% of cases of CIN2 or CIN3, respectively. A similar frequency of Ki-67 or TPII-alpha expression was observed in the dysplastic cells of CIN3 lesions. The pattern of hTERT-positive malignant cells in squamous cell carcinoma and dysplastic cells in the high-grade CIN lesions, to a greater extent, and dysplastic cells in the low-grade CIN lesion, to a lesser extent, was distinct from that of the normal cervical squamous mucosa. The results suggest that the progressive increase in the hTERT expression, together with the proliferative activity of the dysplastic epithelial cells of the high-grade CIN lesions, represents an early genetic abnormality in cervical pathogenesis.
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PMID:Telomerase and markers of cellular proliferation are associated with the progression of cervical intraepithelial neoplasia lesions. 1758 1

The BD ProEx C stain (BD Diagnostics-Tripath, Burlington, NC) detects 2 molecular markers known to be overexpressed in cervical squamous cell carcinoma, minichromosome maintenance protein 2 and topoisomerase II. This study was conducted to evaluate this stain detecting high-grade cervical disease, and results were compared with high-risk HPV (hr-HPV) status and histologic biopsy diagnosis in Papanicolaou tests with atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H) cytologic results. Cervical cytology specimens were collected in BD SurePath preservative (BD Diagnostics-Tripath), and 100 specimens with a diagnosis of ASC-H were included in the study. A second BD SurePath slide, prepared from the residual cellular material from these ASC-H cases, was immunostained using the BD ProEx C reagent. Nuclear staining of ASC-H cells was considered a positive result. The sensitivity for BD ProEx C for detecting cervical intraepithelial neoplasia 2 or worse was 98.8% and for hr-HPV was 71.1%, whereas specificity values were 82.4% and 64.7%, respectively. BD ProEx C has potential as a marker for detection of high-grade disease in patients with ASC-H cytologic results.
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PMID:Detecting high-grade cervical disease on ASC-H cytology: role of BD ProEx C and Digene Hybrid Capture II HPV DNA testing. 1885 69