Endocrine Abstracts

The pituitary progenitors are responsible for generating a fully functional endocrine organ during embryonic development. They also preserve potency, to maintain the homoeostasis in the adult pituitary, being able to respond to endocrine challenges, such as pregnancy or obesity. But the main players of this complex process remain elusive. Eph-Ephrins have been implicated in an increasing number of physiological functions such as axon-guidance, eye field segregation from neural...

Efnb2 encodes for the ligand Ephrinb2 that binds to its cognate Eph receptor, with which plays an integral role in angiogenesis, stem cell regulation and tumorigenesis. Using a pituitary-specific Cre-driver (Hesx1Cre), we conditionally deleted Efnb2 from the early stem/progenitor cells (PSCs) of the developing pituitary gland. We found that Efnb2 is expressed in PSCs both during embryogenesis and adulthood, suggesting its...

Efnb2 plays an integral role during mouse development and in the adult stem cell niche. Efnb2 does encode for Ephrinb2 ligand which then binds to Eph receptor. Preliminary data suggest implication of Efnb2 in pituitary tumours and during normal pituitary embryogenesis. Currently, involvement of Eph:Ephrin signalling pathway in pituitary development is unknown. Better knowledge of Efnb2 in the pituitary will help to improve understanding of endocrine diseases. Deletion of Efnb2...

Efnb2 plays an integral role during mouse development, specifically in angiogenesis and stem cell regulation. Efnb2 encodes for Ephrinb2 ligand that binds to Eph receptor. Preliminary data suggest implications of Efnb2 in pituitary tumors. The involvement of Eph:Ephrin signaling pathway in pituitary development is currently unknown. Better knowledge of Efnb2 in the pituitary will improve the understanding of endocrine disease. Therefore, a pituitary-...

Background: Congenital hypopituitarism (CH) is characterised by the deficiency of one or more pituitary hormones and can present alone or in association with complex disorders. Congenital hyperinsulinism (CHI) is a disorder of unregulated insulin secretion despite hypoglycaemia that can occur in isolation or as part of a syndrome. The underlying genetic etiology causing the complex phenotype of CH and CHI is unknown.Patient and Methods: A female baby bor...

Somatic activating mutations in BRAF, encoding B-Raf, have been described in tumours and recently craniopharyngiomas. Germline mutations in BRAF and other components of the RAS/MAPK pathway are found in RASopathies, whose features include endocrine deficiencies but not craniopharyngiomas. We report three BRAF mutations (two of which are novel) in four children with congenital hypopituitarism. To demonstrate the functional role of the three variants w...

Adamantinomatous craniopharyngiomas (ACPs) are among the most common intracranial tumours in children and they originate from undifferentiated pituitary progenitors. Mutations in the gene encoding for β-catenin (CTNNB1), which lead to the constitutive activation of the Wnt/β-catenin signalling pathway, have been associated with ACP. These tumours can invade adjacent structures, such as the hypothalamus, which makes comp...

Somatic activating mutations in BRAF, encoding B-Raf, have been described in tumours and recently craniopharyngiomas. Germline mutations in BRAF and other components of the RAS/MAPK pathway are found in RASopathies, whose features include endocrine deficiencies but not craniopharyngiomas. We report three BRAF mutations (two of which are novel) in four children with congenital hypopituitarism. To demonstrate the functional role of the three variants w...

Adamantinomatous craniopharyngiomas (ACPs) are among the most common intracranial tumours in children and they originate from undifferentiated pituitary progenitors. Mutations in the gene encoding for β-catenin (CTNNB1), which lead to the constitutive activation of the Wnt/β-catenin signalling pathway, have been associated with ACP. These tumours can invade adjacent structures, such as the hypothalamus, which makes comp...

Introduction: Germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene predispose to growth hormone (GH, 90% of patients) or prolactin (PRL)-secreting tumours, with negligible number of patients with other pituitary tumour types. Animal models of acromegaly are scarce and Aip models have controversial data. Therefore we have generated two pituitary-specific Aip knockout mouse models to study the consequences of loss of AIP p...