Pit-1/GHF-1 expression in pituitary adenomas: further analogy between human adenomas and rat SMtTW tumours.
Adenomas can develop from each cell type of the anterior pituitary. In the normal pituitary, three of these cells types, the GH-, prolactin- and TSH-secreting cells, express the transcription factor Pit-1/GHF-1 which is responsible for prolactin and GH (and probably TSH) cell commitment, differentiation, probably proliferation and gene expression. We have analysed the expression of Pit-1/GHF-1 in a panel of human pituitary adenomas. All GH-, prolactin- and TSH-expressing adenomas studied expressed the Pit-1/GHF-1 factor, as demonstrated by in-situ hybridization and immunocytochemistry. The expression was higher in adenomas than in normal human pituitary. In contrast, ACTH- and LH-FSH-secreting and non-secreting adenomas were negative. Seven transplants of the spontaneous rat prolactinoma SMtTW were also investigated and all were found to be positive. This further stresses the analogy between these tumours and human prolactinomas. Taken together, the data confirm that Pit-1/GHF-1 expression is restricted to GH-, prolactin- and TSH-expressing cells, and the increased expression in adenomas is compatible with a role of Pit-1/GHF-1 in cell proliferation.
Delhase
M
M
Pharmacology Department, Medical School, Free University of Brussels, Belgium.
Vergani
P
P
Malur
A
A
Velkeniers
B
B
Teugels
E
E
Trouillas
J
J
Hooghe-Peters
E L
EL
D000236:Adenoma / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics*; D010908:Pituitary Hormones, Anterior / Q000096:biosynthesis / Q000235:genetics; D010911:Pituitary Neoplasms / Q000235:genetics* / Q000378:metabolism; D051381:Rats; D011920:Rats, Inbred WF; D015398:Signal Transduction; D013045:Species Specificity; D050817:Transcription Factor Pit-1; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*
D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; C494187:POU1F1 protein, human; D010908:Pituitary Hormones, Anterior; C494186:Pou1f1 protein, rat; D050817:Transcription Factor Pit-1; D014157:Transcription Factors