Molecular Pathogenesis of Pituitary Adenomas

The genesis of pituitary tumors is still under debate. Although these neoplasia are monoclonal in origin, mutations of GNAS1, the gene encoding the α subunit of Gs is the only mutational change unequivocally associated with GH-secreting adenomas. In addition, multiple events, including the overexpression of cell cycle regulators, growth factors, and stimulatory hormones together with epigenetic disruption of genes with antioncogenic properties, frequently occur in pituitary tumors; their relative importance is still uncertain.