Glial fibrillary acidic protein and its fragments discriminate astrocytomafrom oligodendroglioma

In the last few years it has been shown that anaplastic oligodendrogliomas, in contrast to anaplastic astrocytomas, are responsive to a three drug reg imen chemotherapy. The histologic criteria for the discrimination between o ligodendrogliomas and astrocytomas are subject to substantial interobserver variability, particularly in anaplastic and mixed gliomas. In the present study a two-dimensional electrophoresis technique (2-DE) has been applied t o glioma samples in an attempt to discriminate the glioma subtypes. It was found that the presence of glial fibrillary acidic protein (GFAP) fragments distinguishes oligodendroglioma from astrocytoma. One-dimensional (1-DE) i mmunoblots were compared with immunohistologically stained tissue sections in which various GFAP-positive cell types were seen. It is concluded that 2 -DE and 1-DE GFAP immunoblotting provide accurate information for the relia ble discrimination of anaplastic astrocytomas and oligodendrogliomas.