Speaker: Gunnar Westin, Professor, Uppsala Universitet

Primary hyperparathyroidism (pHPT) is a common endocrine disease characterized by excessive secretion of PTH from one or more of the parathyroid glands and increased level of serum calcium.

85% of pHPT cases are due to a benign single adenoma and 14% to multiglandular disease.

Parathyroid carcinoma (PC) is rare and accounts for less than 1 to < 5 % of cases of pHPT. A high tendency of local recurrence and current diagnosis relies on demonstration of invasive growth patterns and metastasis.

The TET proteins oxidize the epigenetic mark 5-methylcytosine to 5-hydroxymethylcytosine (5hmC) and inactivation by mutation or epigenetic deregulation of TET1 and TET2 play important roles in various cancers.

Main conclusions that will be discussed here include: The level of 5hmC was suggested a novel biomarker for parathyroid malignancy, and a growth regulatory role of TET1 was demonstrated. Deregulated expression of TET2 due to promoter hypermethylation was detected in PCs, and a role for TET2 in cell growth and migration was demonstrated.