Expression of insulin-like growth factor receptor, IGF-1, and IGF-2 in primary and metastatic osteosarcoma.
OBJECTIVE
We have previously shown that insulin-like growth factor (IGF)-responsive murine sarcomas demonstrate inhibition of local and metastatic disease growth when implanted in an IGF-deficient host animal. In this experiment, we tested whether IGF receptor (IGF-R) and ligands were expressed in human primary and metastatic osteosarcomas.


METHODS
Fifty-two specimens of human osteosarcoma tumor from 48 patients were assayed for IGF-R, IGF-1, and IGF-2 using reverse transcriptase polymerase chain reaction.


RESULTS
Twenty-one of 46 tumors analyzed had levels of expression of IGF-R greater than or equal to the positive control cell line. Twenty-seven of 44 expressed levels of IGF-1 greater than or equal to the positive control, as did 21 of 38 cases assayed for IGF-2. No differences were found between 40 primary tumor samples and 12 metastatic lesions in mean levels of IGF-R, IGF-1, or IGF-2. There was a moderately strong correlation between expression of IGF-R and IGF-1, suggesting that autocrine stimulation may be an important mechanism for stimulation of osteosarcoma proliferation.


CONCLUSIONS
A significant proportion of osteosarcoma tumors express IGF-R and ligands. Higher levels of expression were not correlated with metastatic lesions.
Samuel Lunenfeld Research Institute, Mount Sinai Hospital and the University of Toronto, Ontario, Canada.
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S
Burrow
I L
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Andrulis
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M
Pollak
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RS
Bell
D001859:Bone Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D012516:Osteosarcoma / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D016133:Polymerase Chain Reaction; D017526:Receptor, IGF Type 1 / Q000378:metabolism*; D017527:Receptor, IGF Type 2 / Q000378:metabolism*
D017527:Receptor, IGF Type 2; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D017526:Receptor, IGF Type 1