Expression of insulin-like growth factor-I (IGF-I) in aneurysmal bone cyst

The effects of insulin-like growth factor-I on bone tissue and its role in bone development have been extensively investigated, but there is little in formation on its role in the pathogenesis of aneurysmal bone cyst. Therefor e, using the techniques of immunohistochemistry and in situ hybridization, the authors studied the expression of insulin-like growth factor-I in 19 sp ecimens of aneurysmal bone cyst. Insulin-like growth factor-I or specific m RNA sequences encoding for insulin-like growth factor-I were detectable in all specimens tested and were mainly localized in multinucleate giant cells . In contrast, only insignificant levels of insulin-like growth factor-I ex pression were detectable in normal human bone tissue. Taken together with t he previously reported role of insulin-like growth factor-I in the pathogen esis of giant cell tumor, the findings of this study suggest that insulin-l ike growth factor-I may play a role in the pathogenesis of aneurysmal bone cyst.