Immunohistochemical analysis of 11-beta-hydroxysteroid dehydrogenase type 2 and glucocorticoid receptor in subclinical Cushing's disease due to pituitary macroadenoma.
Subclinical Cushing's disease (SCD) is characterized by lack of clinically evident Cushingoid features, despite abnormal hypersecretion of ACTH. Nearly half the cases of SCD are due to macroadenomas, and in the majority of them, ACTH secretion is not inhibited even by high-dose dexamethasone. Impaired glucocorticoid (GC) action may be correlated with the proliferation and development of pituitary macroadenomas causing SCD. In this study, immunohistochemical analysis of the resected tumors were performed to evaluate the expression of 11beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) and glucocorticoid receptor (GR) in pituitary tissues obtained from two SCD (macroadenomas), eight Cushing's disease (CD) (microadenomas), nine acromegaly, and nine normal pituitary (NP). Scattered 11betaHSD2-immunopositive cells were detected in all NP tissues, but its immunoreactivity was totally absent in any tumorous tissues except two CD. Scattered GR-immunopositive cells were also detected and GR immunostaining was restricted to the cytosol in NP tissue. In contrast, GR-immunopositive cells were abundantly present and GR immunostaining was restricted to the nucleus in all the tumorous tissues. There were marked differences in both expression levels and localization between NP tissues and all the tumors. There may be a mechanism other than that via 11betaHSD2 for causes of impaired negative feedback action by GC in SCD and CD, but results of our present study suggest that impaired GC action may be involved, at least in part, in tumorigenesis of SCD and CD.
Ebisawa
Takanori
T
Division of Diabetes and Endocrinology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105-8461, Japan. tebisawa@jikei.ac.jp
Tojo
Katsuyoshi
K
Tajima
Naoko
N
Kamio
Masami
M
Oki
Yutaka
Y
Ono
Katsuhiko
K
Sasano
Hironobu
H
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000378:metabolism*; D049913:ACTH-Secreting Pituitary Adenoma / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D000172:Acromegaly / Q000378:metabolism / Q000473:pathology; D000236:Adenoma / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D047748:Pituitary ACTH Hypersecretion / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D010902:Pituitary Gland / Q000378:metabolism / Q000473:pathology; D011965:Receptors, Glucocorticoid / Q000378:metabolism*; D055815:Young Adult
D011965:Receptors, Glucocorticoid; D000324:Adrenocorticotropic Hormone; D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2