Endocrine Abstracts

The aryl hydrocarbon receptor interacting protein gene has been mainly involved in the pathogenesis of GH/PRL-secreting pituitary adenomas (PA). We wished to study the significance of AIP expression in clinically non-functioning PA (NFPA).Material and methods: 48 NFPA -27 gonadotroph (GnPA), 21 null cell (ncPA) – were studied for AIP, βFSH and cyclin D1 expression by real-time RT-PCR (qRT), compared with four normal post-mortem pituitaries (NP)...

Radiotherapy (RT) may represent a useful tool in the treatment of GH-secreting tumours in the presence of a post-operative active disease and single dose stereotactic RT/gamma knife is the preferred option in most cases. The effects of RT on the control of hormone secretion are very slow and pharmacological treatment remains necessary for years. Some authors advocate withdrawal of somatostatin analogues (SSA) during RT, although the short-term effects of RT on hormone secretio...

Beta-HLH transcription factors are involved in the ontogenesis of neural/neuroendocrine cells, and may play a role in the pathogenesis of neuroendocrine tumours. Neurogenin 2 (Ngn2) is expressed by the developing mouse pituitary. After preliminary data indicating its expression in the normal human pituitary, we have studied its phenotypic expression in normal and adenomatous pituitary tissues.Methods: Fifty-two pituitary adenomas (PA) – 23 clinicall...

The beta-HLH transcription factors NeuroD1 and ASH1 are frequently expressed by pituitary adenomas, both being present in all corticotroph, most clinically non-secreting (CNS) and a subset of GH and/or PRL-secreting adenomas. We wished to investigate the expression of the related beta-HLH factors neurogenins (Ngn) 1, 2 and 3 in the pituitary (n=4) and in a series of pituitary adenomas (n=45). RT-PCR was performed at different amplification cycles (up to 45) in al...

Peroxisome-proliferator activated receptors (PPARs) are involved in a number of neoplasia. PPARα (PPARα) is a partner of the aryl hydrocarbon receptor interacting protein (AIP), which is involved in the pathogenesis of pituitary adenomas (PA). We wished to investigate the potential expression and biological significance of PPARα in PA, especially in GH/PRL-secreting tumours.Material and methods: A large series of PA was collected (n</e...

The aryl hydrocarbon receptor interacting protein (AIP) gene is abundantly expressed in normal somatotrophs. Somatotropinomas in patients with germline AIP mutations (AIPmut) are typically more aggressive than non-AIPmut adenomas and associated with higher GH/IGF1 secretion. AIP downregulation may also occur in sporadic somatotropinomas, especially in invasive tumours. We wished to evaluate the impact of somatostatin analogues (SSA) pre-treatment on AIP expression in sporadic ...

Background: Germline AIP mutations confer a predisposition to pituitary adenomas (PA), usually in the setting of familial isolated pituitary adenomas (FIPA); AIP mutations account for 50% of familial acromegaly. AIP-related PA are GH, PRL-secreting or non-secreting. Little is known about AIP expression in PA. Although the prevalence is low, identifying AIP mutations in apparently sporadic PA is important for studying at-risk relatives. Pre-screening criteria would help select ...