The Pathophysiology of Pituitary Tumors

Shereen Ezzat; Sylvia L. Asa

doi:10.1055/s-2001-33617

Seminars in Neurosurgery, Table of Contents

Seminars in Neurosurgery 2001; 12(3): 261-272
DOI: 10.1055/s-2001-33617

The Pathophysiology of Pituitary Tumors

Shereen Ezzat^1,4,5 , Sylvia L. Asa^2,3,5

¹Department of Medicine, University of Toronto, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Canada
³Department of Pathology, University Health Network, Toronto, Ontario, Canada
⁴Department of Medicine, Mount Sinai Hospital
⁵Freeman Center for Endocrine Oncology, Toronto, Ontario, Canada

Abstract

ABSTRACT

Numerous factors have been shown to govern pituitary cell proliferation; these various hypophysiotropic hormones and growth factors (GFs) likely play a role as promoters of tumor cell growth in genetically transformed cells. The clonal composition of pituitary adenomas attests to the molecular basis of pituitary tumorigenesis; however, the oncogenes and tumor suppressor genes that are implicated in the transformation events for the vast majority of pituitary tumors remain unknown. Mutations that have been identified in other human malignancies are restricted to a very small subset of pituitary neoplasms implicating novel genetic and/or epigenetic alterations. This review details some of the currently known alterations of GFs and their receptors that have been implicated in pituitary tumorigenesis. Some of the epigenetic changes noted in nuclear components that govern cell cycle control are also reviewed. The emerging knowledge from these studies is shedding new light not only on the pathogenesis of pituitary tumors but on novel mechanisms in the broader context of human neoplasia.

KEYWORDS

Pituitary tumors - growth factors - hypothalamic hormones - FGF receptors

Full Text

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