Expression of interleukin-6, interleukin-6 receptor (gp80), and the receptor's signal-transducing subunit (gp130) in human normal pituitary glands and pituitary adenomas.
Interleukin-6 (IL-6) is an important cytokine in cell proliferation and differentiation in several organs. It has also been reported that IL-6 plays a role in secretion or release of pituitary hormones in pituitary hormone-secreting cells and pituitary adenomas, but convincing data in situ have not yet been reported. In this study, we examined the participation of IL-6 in the production of pituitary hormones and the differences between human normal pituitary glands and pituitary adenomas by determination of the localization or expression of IL-6, IL-6 receptor (IL-6R, gp80), and the signal-transducing subunit (gp130) of the receptor using immunohistochemical staining and RT-PCR. IL-6 was mainly expressed in ACTH- and FSH/LH-secreting cells in normal pituitary glands, as shown by double staining. gp 80 and gp130 were coexpressed in almost all GH- and PRL-secreting cells and in approximately 30% of FSH/LH-secreting cells. RT-PCR showed that IL-6 mRNA was expressed in only one of all the pituitary adenomas examined, whereas gp 80 and gp 130 mRNAs were detected in all these pituitary adenomas. In conclusion, IL-6 was mainly expressed in ACTH- and FSH/LH-secreting cells, and the receptors were expressed in GH-, PRL- and FSH/LH-secreting cells in human normal pituitary glands. Furthermore, our data emphasized that the mechanism of IL-6 function in human pituitary adenoma cells is distinct from that in normal pituitary cells.
Kurotani
R
R
Department of Pathology, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan.
Yasuda
M
M
Oyama
K
K
Egashira
N
N
Sugaya
M
M
Teramoto
A
A
Osamura
R Y
RY
D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000032:analysis / Q000235:genetics*; D050822:Cytokine Receptor gp130; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000032:analysis / Q000235:genetics*; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis / Q000235:genetics*; D008875:Middle Aged; D010902:Pituitary Gland / Q000378:metabolism* / Q000473:pathology; D010907:Pituitary Hormones / Q000032:analysis; D010911:Pituitary Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019947:Receptors, Interleukin-6 / Q000032:analysis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D009418:S100 Proteins / Q000032:analysis
D015703:Antigens, CD; C494199:IL6ST protein, human; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D010907:Pituitary Hormones; D012333:RNA, Messenger; D019947:Receptors, Interleukin-6; D009418:S100 Proteins; C113250:interleukin-6 receptor alpha; D050822:Cytokine Receptor gp130