PMID- 9143002
OWN - NLM
STAT- MEDLINE
DCOM- 19970718
LR  - 20180214
IS  - 0028-3835 (Print)
IS  - 0028-3835 (Linking)
VI  - 65
IP  - 4
DP  - 1997 Apr
TI  - Immunohistochemical expression of retinoid X receptor isoforms in human 
      pituitaries and pituitary adenomas.
PG  - 299-306
AB  - Retinoid X receptors (RXRs) are transcriptional factors that belong to the 
      steroid/thyroid hormone receptor superfamily. There are 3 RXR isoforms-alpha, 
      beta, gamma-known to bind 9-cis-retinoic acid as their ligand. The expression of 
      RXRs in human pituitary glands and pituitary adenomas has not been extensively 
      investigated. To determine whether specific RXR isoforms may play roles in the 
      state of differentiation of pituitary adenomas, we have investigated the 
      immunohistochemical expression of RXR alpha and RXR gamma in 6 nontumorous 
      pituitaries and in 60 different pituitary adenomas using isoform-specific 
      antibodies. In the nontumorous pituitaries. RXR alpha was expressed in the nuclei 
      of almost all cells, while RXR gamma was only expressed in thyrotropin (TSH) 
      cells and in some cells positive for growth hormone (GH) and glycoprotein 
      alpha-subunit (alpha SU) but not in luteinizing hormone (LH) beta-subunit, 
      follicle-stimulating hormone (FSH) beta-subunit, prolactin (PRL) or 
      adrenocorticotropin (ACTH) cells by double immunostaining. All 60 adenomas were 
      RXR alpha positive, and 39 of 60 adenomas (65%) were positive for RXR gamma. The 
      incidence of RXR gamma immunoreactivity in the different adenoma types was: 13 of 
      16 GH-producing adenomas (81.3%), 9 of 14 PRL-secreting adenomas (64.3%), 6 of 6 
      TSH-secreting adenomas (100%), 2 of 5 ACTH-secreting adenomas (40%) and 9 of 19 
      nonfunctioning adenomas (47.4%) including immunohistochemically 
      gonadotropin-subunit-positive adenomas. The colocalization of RXR gamma with the 
      TSH beta subunit, GH and alpha SU in the same adenoma cells was frequently 
      observed, and sometimes RXR gamma was colocalized with PRL, ACTH, FSH beta or LH 
      beta as shown by double immunostaining. We conclude that RXR alpha is expressed 
      in both human pituitaries and pituitary adenomas. In contrast, RXR gamma is 
      expressed more broadly in pituitary adenomas than in normal pituitaries and thus 
      may play a role in the differentiation-specific cell types in the human pituitary 
      both under physiological and pathological conditions.
FAU - Sanno, N
AU  - Sanno N
AD  - Department of Pathology, Tokai University School of Medicine, Kanagawa, Japan.
FAU - Sugawara, A
AU  - Sugawara A
FAU - Teramoto, A
AU  - Teramoto A
FAU - Abe, Y
AU  - Abe Y
FAU - Yen, P M
AU  - Yen PM
FAU - Chin, W W
AU  - Chin WW
FAU - Osamura, R Y
AU  - Osamura RY
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Switzerland
TA  - Neuroendocrinology
JT  - Neuroendocrinology
JID - 0035665
RN  - 0 (Receptors, Retinoic Acid)
RN  - 0 (Retinoid X Receptors)
RN  - 0 (Transcription Factors)
SB  - IM
MH  - Adenoma/*metabolism
MH  - Adult
MH  - Aged
MH  - Female
MH  - Humans
MH  - Immunohistochemistry
MH  - Male
MH  - Middle Aged
MH  - Pituitary Gland/*metabolism
MH  - Pituitary Neoplasms/*metabolism
MH  - Receptors, Retinoic Acid/*metabolism
MH  - Retinoid X Receptors
MH  - Transcription Factors/*metabolism
EDAT- 1997/04/01 00:00
MHDA- 1997/04/01 00:01
CRDT- 1997/04/01 00:00
PHST- 1997/04/01 00:00 [pubmed]
PHST- 1997/04/01 00:01 [medline]
PHST- 1997/04/01 00:00 [entrez]
AID - 10.1159/000127188 [doi]
PST - ppublish
SO  - Neuroendocrinology. 1997 Apr;65(4):299-306. doi: 10.1159/000127188.