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Updated: Aug 13, 2026
08:34
Utilizing Murine Inducible Telomerase Alleles in the Studies of Tissue Degeneration/Regeneration and Cancer
Published on: April 13, 2015
Topoisomerase II alpha and telomerase expression in papillary thyroid carcinomas
L Karayan-Tapon1, E Menet, J Guilhot
1Laboratoire de Protéines et Inflammation, CHU la Milétrie, 86021 Poitiers Cedex, France.
Summary
Topoisomerase II alpha (Topo II alpha) expression is not a reliable marker for tumor aggressiveness in papillary thyroid carcinoma (PTC). However, elevated Topo II alpha in younger patients suggests potential benefit from specific chemotherapy.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Altered expression of topoisomerase II alpha (Topo II alpha) and telomerase activity (TA) are indicators of tumor cell proliferation and malignant transformation.
- These markers play a role in understanding tumor behavior and progression.
Purpose of the Study:
- To investigate the expression of Topo II alpha and TA in papillary thyroid carcinoma (PTC).
- To determine the correlation of Topo II alpha expression and TA with clinicopathological features and patient age.
- To evaluate the potential of Topo II alpha as a marker for tumor aggressiveness and therapeutic target.
Main Methods:
- Examined TA using a TRAP assay in 27 PTC cases.
- Assessed Topo II alpha expression via immunohistochemical analysis.
- Correlated Topo II alpha labeling index (LI) and TA levels with patient age and other clinical outcomes.
Main Results:
- Topo II alpha LI ranged from 0.1% to 4.2% and was significantly associated with patient age (r=-0.42, p=0.003), with higher levels observed in patients under 40 years.
- No significant relationship was found between Topo II alpha LI and tumor aggressiveness or other clinical outcomes.
- TA was detected in 14 PTC cases, with levels ranging from 1.2 to 102 units.
- A significant positive correlation was noted between the multiplicity of tumoral foci and TA levels (p<10(-2)).
Conclusions:
- Topo II alpha is not a suitable marker for assessing tumor aggressiveness in PTC.
- Enhanced Topo II alpha expression in PTCs from patients under 40 years old suggests this demographic may benefit from Topo II inhibitor chemotherapy.
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