Endocrine Abstracts

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...

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. ...