Endocrine Abstracts

BackgroundCorticotroph pituitary adenomas present different degrees of functionality, from silent to whispering and finally to functioning adenomas leading to Cushing’s disease. Compared to their functioning (FCA) counterpart, the silent corticotroph adenomas (SCA) express lower levels of the corticotroph cell lineage marker–TBX19 (TPIT), proopiomelanocortin (POMC), and prohormone converting enzyme 1/3 (PC1/3, PCSK1)–t...

Purpose: Clinically Non-Functioning Pituitary Neuroendocrine Tumours (NF-PitNETs) present a varying degree of aggressiveness, and reliable prognostic markers are lacking. We aimed to characterize the distribution of E- and N-cadherin in corticotroph, PIT1 and null-cell NF-PitNETs, and link it to the clinical course of the tumours.Methods: We investigated the distribution of E- and N-cadherin by immunohistochemistry in a retrospective cohort of thirty tum...

Background: Real-time reverse transcription quantitative PCR (RT-qPCR) has become the method of choice for quantification of gene expression changes. Inappropriate data normalization and inconsistent data analyses are some limitations of RT-qPCR. Pituitary adenomas are frequent tumours and the interpretation of increasingly published data within this field is hindered by the lack of a proper selection and validation of stably expressed reference genes.Ai...

Background: Functioning (FCA) and silent corticotroph (SCA) pituitary adenomas act differently from a clinical perspective, despite both subtypes showing positive ACTH staining by immunohistochemistry. They are challenging to treat, the former due to functional ACTH production and consequently hypercortisolemia leading to Cushing disease, whereas the latter due to invasive and recurrent behaviour. Moreover, the molecular mechanisms behind their distinct behaviour are not clear...

Objectives: To study the effect of epithelial-to-mesenchymal transition (EMT) on hormone expression in gonadotroph non-functioning pituitary neuroendocrine tumours (NF-PitNET).Background: Gonadotroph PitNETs can express FSH and LH or be hormone negative, however they rarely secrete hormones. During tumour development, epithelial cells develop a mesenchymal phenotype. This process is characterised by decreased membranous E-cadherin and translocation of E-...

Background: The exact mechanism behind the hypersecretion of ACTH and lack of negative cortisol feedback on POMC regulation in functional corticotroph adenomas (FCA) is unknown. Silent corticotroph adenomas (SCA) express, but do not secrete functional ACTH and have lower POMC expression. Using RT-qPCR and immunohistochemistry, previous studies have identified some POMC-transcription factors, regulators and processing enzymes to be differentially expressed between FCA and SCA. ...

Background: Non-functioning pituitary adenomas (NFPAs) necessitate prolonged clinical, biochemical and radiological observation, constituting a significant burden in terms of medical resources and societal costs. Reliable biomarkers associated with aggressiveness and recurrence of NFPAs are lacking. As the growth of tumor remnants is highly variable, molecular markers that can predict growth potential and tumor behavior are necessary.Aim: To identify tar...