Endocrine Abstracts

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor that originates from parafollicular thyroid C cells and accounts for 5% -10% of thyroid cancers. In all inherited cases of MTC, and in about 40% of sporadic cases, activating mutations of the receptor tyrosine kinase proto-oncogene RET are found. Constitutively active RET triggers signaling pathways involved in cell proliferation, survival and motility, but the mechanisms underlying malignant transformation of C-...

Progressive osseous heteroplasia (POH) is a rare autosomal dominant disorder of mesenchymal differentiation characterized by progressive heterotopic ossification (HO) of dermis, skeletal muscle and deep connective tissues. Initially HO occurs during infancy as osteoma cutis, then extends progressively into deep connective tissues during childhood. Most cases of POH are caused by paternally inherited mutations of GNAS gene. Maternal mutations as well as epigentic defec...

The two main subtypes of pseudohypoparathyroidism (PHP), PHP-Ia and -Ib, are caused by mutations in GNAS exons 1–13 and methylation defects in the imprinted GNAS cluster, respectively. PHP-Ia patients show Albright hereditary osteodystrophy (AHO) and resistance toward PTH and additional hormones, while PHP-Ib patients do not have AHO and hormone resistance is limited to PTH and TSH. Recently, methylation defects have been detected in 5 patients with PHP-Ia, indicating a m...

Background: Several criteria (i.e., cortisol supprimibility after 1 mg overnight dexamethasone suppression test -F-dex-, low ACTH levels, high 24 h urinary free cortisol levels -UFC-, high midnight serum cortisol levels) have been used for defining SH. Nevertheless, a real gold standard combination of tests is lacking. Recently midnight salivary cortisol (MSC) has been described as a sensitive marker for the diagnosis of overt hypercortisolism, while the role of MSC in the dia...