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Updated: Dec 2, 2025

Simple and Fast Rolling Circle Amplification-Based Detection of Topoisomerase 1 Activity in Crude Biological Samples
Published on: December 2, 2022
Implications of Topoisomerase (TOP1 and TOP2α) Expression in Patients With Breast Cancer
Misato Ogino1,2,3, Takaaki Fujii4,2, Yuko Nakazawa1,2
1Division of Breast and Endocrine Surgery, Graduate School of Medicine, Gunma University, Gunma, Japan.
Background/Aim:
We evaluated the usefulness of topoisomerases (TOPs) expression as prognostic predictors in breast cancer.
Patients And Methods:
We retrospectively investigated sixty cases with primary breast cancer. We evaluated the tumor and non-tumor mRNA levels of TOP1 and TOP2α using quantitative reverse-transcription polymerase chain reaction. TOP1/TOP2α positivity was defined as the ratio of the mRNA expression of cancer/normal tissue of >1 for both TOP1 and TOP2α.
Results:
TOP1 and TOP2α were markedly overexpressed in breast cancer tissues compared to normal breast tissues. Of the 60 cases, 46 (76.7%) were positive for TOP1/TOP2α. The relapse-free survival was relatively shorter for patients with positive TOP1/TOP2α. There was no recurrent disease among the 14 patients who were negative for TOP1/TOP2α, whereas four of the 46 TOP1/TOP2α-positive patients had disease recurrence.
Conclusion:
Negative TOP1 or TOP2α expression may be useful for predicting better prognoses in breast cancer patients.
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