Endocrine Abstracts

Background: Aryl hydrocarbon receptor interacting protein (AIP) mutations have been identified in ~15% of patients with familial isolated pituitary adenomas (FIPA). In addition, dysregulation of the cyclic adenosine monophosphate (cAMP) signalling pathway has been identified in both syndromic and sporadic somatotropinomas. While crosstalk between these two systems is known to occur, the exact mechanism of interaction remains elusive. The identification of direct binding...

Germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene predispose to early onset pituitary adenoma, with a preponderance of somatotrophinomas. Patients harbouring an AIP mutation respond poorly to somatostatin analogue (SSA) treatment. On the other hand, a subset of sporadic somatotrophinomas with no AIP mutations show low AIP protein expression and exhibit a decreased response to SSA treatment as well. microRNAs are small...

Neuroendocrine neoplasms (NENs) are rare tumour showing a wide spectrum of clinical behaviours. Therapeutic options available for NET treatment are rarely curative and mostly palliative, as NETs frequently show resistance to pharmacological therapy. Cancers develop in complex tissue environments, which they depend on. Tumour-associated macrophages (TAMs) are a major cellular component of the tumour microenvironment. Two polarized state of macrophages are described in literatur...

Background: Abnormal microRNAs (miRNAs) expression profiles have been recently associated with sporadic pituitary adenomas, suggesting that miRNAs can contribute to tumor formation. miRNAs are small noncoding RNAs which inhibit post-transcriptional expression of target mRNAs by binding to complementary sequences usually located in the 3′ untranslated region (3′UTR). However, the substantial lack of knowledge about miRNAs’ targets hinder full understanding of t...

Background: The fourth type of Multiple Endocrine Neoplasia (MEN) is a rare variant of MEN presenting a MEN1-like phenotype and originating from a germline mutation in CDKN1B. However, due to the small number of cases documented in literature, the peculiar clinical features of MEN4 are still largely unknown, and clear indications about the clinical management of these patients are currently lacking. In order to enlarge our knowledge on MEN4 and to better typify the clinical fe...

Locus-specific databases (LSDBs) have been recently developed in response to the increasing number of genetic changes reported in the human genome. LSDBs have been created for several genes implicated in endocrine syndromes, for example MEN1, VHL, RET, GNAS, PRKAR1A and the SDH subunits. Mutations in AIP are found in about 20% of familial isolated pituitary adenoma (FIPA) patients.The aim of this proj...

Background: 20% of the familial isolated pituitary adenoma (FIPA) population harbour an aryl hydrocarbon receptor-interacting protein (AIP) gene mutation. The recognition of whether a variant is pathogenic can be difficult, in cases where the observed change does not lead to a truncated protein. Segregation with disease in a family, in silico predictions, loss of heterozigosity in the tumour, in vitro functional studies and screening of the variant in controls may help in asce...

Increased secretion of GH results in gigantism in children/adolescents and in acromegaly in adults; the relative roles of the various genetic causes of acromegaly and gigantism are still unclear. To analyse the genetic causes and inherited/familial features in patients with pituitary gigantism, we studied a large international cohort. Genetic or inherited characteristics were observed in 39% of patients and included familial isolated pituitary adenomas (FIPA; n=28), M...

Background: Botulinum neurotoxin inhibits muscle function by interfering with neurotransmitter release from secretory vesicles. The mechanism underlying this effect involves cleavage of SNARE proteins which are required for vesicle docking at the plasma membrane. The ability of botulinum neurotoxin serotypes to cleave SNARE proteins and inhibit secretion is being exploited for therapeutic purposes by Syntaxin Ltd with their ‘targeted secretion inhibitor technology’ (...

Background: Familial isolated pituitary adenomas (FIPA) is a rare inherited disorder accounting for about 2% of pituitary adenomas. Mutations in the Aryl hydrocarbon receptor Interacting Protein (AIP) gene have been described in about 15% of FIPA families and rarely in early onset sporadic pituitary adenomas. Among the AIP mutations reported so far, the R304X represents, after the Finnish founder mutation Q14X, the second most common one.Me...