Clonal Origin of Pituitary Adenomas

摘要: As the pathogenesis of pituitary adenomas remains unclear, tumor clonal composition these common neoplasms was studied. Clonality determined in female patients by analysis restriction fragment length polymorphisms X-chromosome genes hypoxanthine phosphoribosyl transferase and phosphoglycerate kinase conjunction with their respective methylation patterns. Peripheral lymphocyte DNA screened from 62 undergoing transsphenoidal surgery for adenoma. Eleven were heterozygous BglI site on PGK, 4 BamHI HPRT, 1 patient both sites. Of 16 patients, 3 had acromegaly, Cushing's disease, 7 hyperprolactinemia, 2 clinically nonfunctional. After surgery, morphological study, including immunohistochemistry electron microscopy pathological specimens, allowed a direct comparison between clonality cell type. Control fresh normal tissue found to be polyclonal. The following tumors monoclonal: all somatotroph adenomas, lactotroph tumors, corticotroph gonadotroph adenoma, nonsecretory A mixed plurihormonal adenoma polyclonal, as consisting adenomatous lactotrophs interspersed nontumorous adenohypophyseal one tissue. Functional derived somatotrophs, corticotrophs, or are monoclonal nature, suggesting that somatic mutations precede expansion cells play major role tumorigenesis.