The expression of angiogenin in tissue samples of different brain tumours and cultured glioma cells.

Abstract

BACKGROUND: As a potential angiogenetic factor the 14.1 kDa polypeptide angiogenin induces neovascularisation. MATERIALS AND METHODS: We investigated the angiogenin expression by immunoblotting and an ELISA in 60 tissue specimens (40 gliomas, 20 other intracranial tumours), in 22 glioma cell cultures and in 4 supernantants of cultivated glioblastoma cells. RESULTS: We could show that angiogenin is detectable in different kinds of intracranial tumours with the highest amount in meningiomas and the lowest amount in low grade astrocytomas. In tissue specimens, a significantly higher angiogenin expression was measured in meningiomas compared to gliomas and metastases. Angiogenin could be detected in primary cultivated glioma cells, but not in the permanent cell lines. There was a significant correlation to the malignancy within the gliomas with an increase of angiogenin concentration according to the higher grade of malignancy. CONCLUSIONS: Our data suggest that angiogenin may contribute to the malignant transformation of gliomas and could perhaps advise that the physiological role of angiogenin is not restricted exclusively to angiogenesis. Based on these findings the clinical importance of angiogenin for therapeutic decisions in malignant brain tumours remains unclear and further analyses on m-RNA-levels are required.