A comparative study of the int-2 gene product in primary and secondary parathyroid lesions.
OBJECTIVE
The family of fibroblast growth factors stimulates proliferation of cells of mesenchymal, epithelial and neuroectodermal origin. One of the members of this family, the product of proto-oncogene int-2, fibroblast growth factor-3, has been found to stimulate mitosis of parathyroid cells in culture. Primary and secondary hyperparathyroidism have no clear differences with regard to the histopathological features of the diseased parathyroid glands.


METHODS
This study was undertaken in order to determine whether int-2 protein is immunohistochemically expressed in normal and abnormal parathyroid glands and to investigate whether there is a differential expression of the int-2 gene product between primary and secondary parathyroid disease.


METHODS
A sheep anti-human int-2 antibody was applied to tissue sections from 37 samples of primary parathyroid disease (12 sporadic adenomas, 25 hyperplastic glands), from 30 samples of renal hyperparathyroidism, and from seven normal controls. Int-2 immunostaining was evaluated semi-quantitatively.


RESULTS
None of the normal parathyroid glands stained positively. Int-2 immunopositive expression was more frequently detected in specimens of uraemic patients than in those of patients with primary parathyroid growth processes (P=0.029). The reason for this differential expression appears to be the higher proportion of oxyphilic cells growing in hyperplastic glands of patients with secondary hyperparathyroidism; the latter cells were specifically found to be int-2 immunoreactive.


CONCLUSIONS
The int-2 gene product is likely to participate in the proliferation of this parathyroid cell subpopulation.
Tseleni-Balafouta
Sofia
S
Department of Pathology, School of Medicine, The National and Capodistrian University of Athens, Athens, Greece. alazaris@cc.uoa.gr
Thomopoulou
Georgia
G
Lazaris
Andreas Ch
ACh
Koutselini
Helen
H
Davaris
Panayiotis S
PS
D000236:Adenoma / Q000378:metabolism / Q000473:pathology; D051518:Fibroblast Growth Factor 3; D005346:Fibroblast Growth Factors / Q000378:metabolism*; D006801:Humans; D006961:Hyperparathyroidism / Q000378:metabolism* / Q000473:pathology; D006962:Hyperparathyroidism, Secondary / Q000378:metabolism* / Q000473:pathology; D006965:Hyperplasia / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D010280:Parathyroid Glands / Q000378:metabolism* / Q000473:pathology; D010282:Parathyroid Neoplasms / Q000378:metabolism / Q000473:pathology; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
C496444:FGF3 protein, human; D051518:Fibroblast Growth Factor 3; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D005346:Fibroblast Growth Factors