Type 2 deiodinase is expressed in anaplastic thyroid carcinoma and its inhibition causes cell senescence.

Anaplastic thyroid cancer (ATC) is a rare thyroid tumor that frequently originates from the dedifferentiation of a well-differentiated papillary or follicular thyroid cancer. Type 2 deiodinase (D2), responsible for the activation of the thyroid hormone thyroxine into tri-iodothyronine (T3), is expressed in normal thyroid cells and its expression is strongly downregulated in papillary thyroid cancer. In skin cancer, D2 has been associated with cancer progression, dedifferentiation, and epithelial-mesenchymal transition.

Deiodinases in thyroid tumorigenesis.

The three deiodinase selenoenzymes are key regulators of intracellular thyroid hormone (TH) levels. The two TH-activating deiodinases (type 1 deiodinase and type 2 deiodinase (D2)) are normally expressed in follicular thyroid cells and contribute to overall TH production. During thyroid tumorigenesis, the deiodinase expression profile changes to customize intracellular TH levels to different requirements of cancer cells.

Left ventricle relative wall thickness and plasma leptin levels: baseline relationships and effects of 4 months of walking training in healthy overweight postmenopausal women.

Objective: Whether leptin has positive or negative influences on cardiac structure and function in healthy sedentary overweight postmenopausal women is unknown. We investigated the role of leptin in cardiac health and whether aerobic fitness enhancement influences any relationships revealed between leptin and echocardiographic measurements.

Methods: Thirty-nine sedentary postmenopausal women were enrolled after an initial screening.