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Thyroid hormones and selenium status in breast cancer
J J Strain1, E Bokje, P van't Veer
1Human Nutrition Research Group, University of Ulster, Coleraine, Northern Ireland.
Nutrition and Cancer
|January 1, 1997
Summary
Lower plasma triiodothyronine (T3) levels are linked to postmenopausal breast cancer. Selenium status may influence T3 levels, potentially impacting breast cancer risk.
Area of Science:
- Endocrinology
- Nutritional Science
- Oncology
Background:
- Thyroid hormones play crucial roles in metabolism and cellular function.
- Selenium is an essential trace element with antioxidant properties and is vital for thyroid hormone metabolism.
- Alterations in thyroid hormone levels have been investigated in relation to various cancers, including breast cancer.
Purpose of the Study:
- To compare thyroid hormone levels between postmenopausal breast cancer patients and healthy controls.
- To investigate the correlation between plasma triiodothyronine (T3) and toenail selenium concentrations.
- To explore the potential role of selenium status in thyroid hormone regulation in the context of early-stage breast cancer.
Main Methods:
- A case-control study involving 99 postmenopausal breast cancer patients and 105 matched healthy controls.
- Measurement of plasma concentrations of triiodothyronine (T3), thyroxine, and thyroid-stimulating hormone.
- Analysis of toenail selenium concentrations as a biomarker of long-term selenium status.
- Statistical analysis to compare hormone levels and correlate them with selenium concentrations and breast cancer status.
Main Results:
- Plasma T3 levels were significantly lower in breast cancer cases compared to controls.
- A strong inverse relationship was observed between T3 levels and breast cancer risk (OR 0.17).
- Plasma T3 concentration showed a positive association with toenail selenium in both cases and controls.
Conclusions:
- Lower plasma T3 levels may be associated with postmenopausal breast cancer.
- Selenium status might influence T3 levels, potentially through the selenoenzyme type 1 iodothyronine deiodinase.
- Further research is warranted to elucidate the interplay between selenium, thyroid hormones, and breast cancer development.
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