Pituitary tumors: genetic and molecular factors underlying pathogenesis and clinical behavior

Pituitary neuroendocrine tumors (PitNETs) are the most common intracranial neoplasms. Although generally benign, they can show a clinically aggressive course, with local invasion, recurrences and resistance to medical treatment. No universally accepted biomarkers of aggressiveness are available yet, and predicting clinical behavior of PitNETs remains a challenge. In rare cases the presence of germline mutations in specific genes predisposes to PitNETs formation, as part of syndromic diseases or familial isolated pituitary adenomas (FIPA), and associates to more aggressive, invasive and drug resistant tumors. The vast majority of cases is represented by sporadic PitNETs. Somatic mutations in the  subunit of stimulatory G protein gene (gsp) and in the ubiquitin-specific protease 8 (USP8) gene have been recognized as pathogenetic factors in sporadic GH- and ACTH-secreting PitNETs, respectively, without an association with a worse clinical phenotype. Other molecular factors have been found to significantly affect PitNETs drug responsiveness and invasive behavior. These molecules are cytoskeleton and/or scaffold proteins whose alterations prevent proper functioning of the somatostatin and dopamine receptors, targets of medical therapy, or promote the ability of tumor cells to invade s urrounding tissues. The aim of the present review is to provide an overview of the genetic and molecular alterations that can contribute to determine PitNETs clinical behavior. Understanding su...
Source: Neuroendocrinology - Category: Endocrinology Source Type: research