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Simple and Fast Rolling Circle Amplification-Based Detection of Topoisomerase 1 Activity in Crude Biological Samples
Published on: December 2, 2022
Human DNA topoisomerase II-alpha
J Martinchick1, M Rahn, C Jolles
1UNIV UTAH,HLTH SCI CTR,DEPT PATHOL,SALT LAKE CITY,UT 84132.
International Journal of Oncology
|May 3, 2011
Summary
DNA topoisomerase II-alpha (topo II-alpha) is a proliferation marker in ovarian tumors. High topo II-alpha levels correlate with cell proliferation and may identify patients treatable with targeted anticancer drugs.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- DNA topoisomerase II-alpha (topo II-alpha) is a target for anticancer drugs and a proliferation marker.
- Ovarian neoplasms may benefit from topoisomerase-targeting therapies, but data on enzyme expression are limited.
- Topo II-alpha levels are high during S and G2 cell cycle phases.
Purpose of the Study:
- To investigate topo II-alpha expression in human ovarian neoplasms.
- To correlate topo II-alpha expression with cell proliferation marker MIB1.
- To assess c-erbB-2 oncogene amplification in relation to topo II-alpha.
Main Methods:
- Immunohistochemical staining for topo II-alpha in 30 ovarian neoplasms.
- Correlation analysis with MIB1 expression.
- Evaluation of c-erbB-2 gene amplification.
Main Results:
- Topo II-alpha expression strongly correlates with MIB1, indicating its utility as a proliferation marker in ovarian tumors.
- One of 15 malignant ovarian neoplasms showed high topo II-alpha levels.
- No amplification of the c-erbB-2 oncogene was observed.
Conclusions:
- Topo II-alpha is a reliable marker for cell proliferation in ovarian tumors.
- Topo II-alpha immunostaining may identify ovarian cancer patients who could benefit from topoisomerase II-targeted therapies.
- Further research is warranted to explore the therapeutic potential of topo II-alpha targeted drugs in ovarian cancer.
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