Influence of thyroid hormone receptors on breast cancer cell proliferation

• Published in: Annals of oncology Vol. 17; no. 1; pp. 60 - 64
• Main Authors: Conde, I., Paniagua, R., Zamora, J., Blánquez, M. J., Fraile, B., Ruiz, A., Arenas, M. I.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.01.2006; Oxford Publishing Limited (England)
• Subjects: Antineoplastic agents; Biological and medical sciences; Blotting, Western; breast; Breast - metabolism; Breast cancer; Breast Diseases - metabolism; Breast Diseases - pathology; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; cancer; Carcinoma in Situ - metabolism; Carcinoma in Situ - pathology; Carcinoma, Ductal, Breast - metabolism; Carcinoma, Ductal, Breast - pathology; Carcinoma, Lobular - metabolism; Carcinoma, Lobular - pathology; Cell Proliferation; Disease Progression; Female; Fibroadenoma - metabolism; Fibroadenoma - pathology; Gynecology. Andrology. Obstetrics; Humans; Immunohistochemistry; Mammary gland diseases; Medical sciences; Pharmacology. Drug treatments; proliferation; Receptors, Thyroid Hormone - metabolism; thyroid hormone receptors; Tumors; Cell proliferation; Mammary gland diseases; proliferation; Thyroid hormone; Breast cancer; cancer; Mammary gland; Malignant tumor; breast; Tumor cell; Hormonal receptor; thyroid hormone receptors
• ISSN: 0923-7534; 1569-8041
• DOI: 10.1093/annonc/mdj040

Background: The involvement of thyroid hormones in the development and differentiation of normal breast tissue has been established. However, the association between breast cancer and these hormones is controversial. Therefore, the objective of the present study was to determine the protein expression pattern of thyroid hormone receptors in different human breast pathologies and to evaluate their possible relationship with cellular proliferation. Patients and methods: The presence of thyroid hormone receptors was evaluated by immunohistochemistry and western blot analysis in 84 breast samples that included 12 cases of benign proliferative diseases, 20 carcinomas in situ and 52 infiltrative carcinomas. Results: TR-α was detected in the nuclei of epithelial cells from normal breast ducts and acini, while in any pathological type this receptor was located in the cytoplasm. However, TR-β presented a nuclear location in benign proliferative diseases and carcinomas in situ and a cytoplasmatic location in normal breast and infiltrative carcinomas. The highest proliferation index was observed in carcinomas in situ, although in infiltrative carcinomas an inverse correlation between this index and the TR-α expression was encountered. Conclusions: The results of this study reveal substantial changes in the expression profile of thyroid hormone receptors suggesting a possible deregulation that could trigger breast cancer development.