Expression of insulin-like growth factors and their receptors in human meningiomas.
Meningiomas have previously been shown to highly express the gene for insulin-like growth factor-II (IGF-II), and receptors for IGF-I have been demonstrated by binding studies in membranes prepared for meningiomas. The co-expression of insulin and the insulin-like growth factors with their corresponding receptors in meningiomas has not been explored. Immunofluorescence microscopy was carried out on twelve meningotheliomatous meningiomas using antibodies directed against insulin, IGF-I, IGF-II, insulin receptor and IGF-I receptor. In addition, these results were contrasted with similar studies using antibodies against desmoplakin and basic fibroblast growth factor. Although insulin immunoreactivity was detected in only one tumor, IGF-I and IGF-II immunoreactivity was present in six and eight of the tumors, respectively. In addition, the IGF-I receptor was expressed in four of the tumors while the insulin receptor was expressed in 10 out of 12 meningiomas. The pattern of distribution of IGF-II and the insulin receptor was especially regional. The insulin-like growth factors and their receptors are expressed in meningiomas in a pattern of distribution suggestive of a paracrine mechanism.
Lichtor
T
T
Department of Neurological Surgery, Loyola University Medical Center, Chicago, Illinois.
Kurpakus
M A
MA
Gurney
M E
ME
D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000378:metabolism; D008577:Meningeal Neoplasms / Q000378:metabolism*; D008579:Meningioma / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D011972:Receptor, Insulin / Q000378:metabolism; D017451:Receptors, Somatomedin / Q000378:metabolism*; D013002:Somatomedins / Q000378:metabolism*
D017451:Receptors, Somatomedin; D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D011972:Receptor, Insulin