Progesterone Upregulates Gene Expression in Normal Human Thyroid Follicular Cells

Area of Science:

• Endocrinology
• Molecular Biology
• Oncology

Background:

• Thyroid cancer and nodules are more common in women, suggesting a role for female sex hormones.
• Limited data exists on progesterone's direct impact on thyroid cells.

Purpose of the Study:

• To investigate the direct effects of progesterone on gene expression in normal human thyroid follicular cells.
• To assess progesterone's influence on key genes involved in thyroid function and proliferation, including sodium-iodide symporter (NIS), thyroglobulin (TG), thyroperoxidase (TPO), and Ki-67.

Main Methods:

• Human thyroid follicular cells were treated with thyroid-stimulating hormone (TSH) and progesterone.
• Gene expression levels of NIS, TG, TPO, and Ki-67 were quantified using mRNA analysis.
• The effects of progesterone were further examined using mifepristone, a progesterone receptor antagonist.

Main Results:

• TSH significantly upregulated NIS, TG, TPO, and Ki-67 mRNA expression.
• Progesterone, in combination with TSH, further increased NIS, TG, and Ki-67 mRNA expression.
• Progesterone also showed a trend towards increasing TPO mRNA expression, and these effects were reversed by mifepristone.

Conclusions:

• Progesterone directly influences thyroid follicular cells, upregulating genes critical for thyroid function and cell proliferation.
• These findings provide evidence for a direct etiological role of progesterone in thyroid diseases prevalent in women.