Glial fibrillary acidic protein in medulloblastoma

Abstract

Twenty-four cases of classical medulloblastoma and one case of desmoplastic medulloblastoma were examined for glial fibrillary acidic protein (GFAP) using the immunoperoxidase method to assess astrocytic differentiation. In 16 cases of classical medulloblastoma GFAP-positive cells were present in variable numbers. These cells were classified as three different types according to size and shape. The type 1 cell was morphologically identical to the ordinary tumor cell, with a hyperchromatic nucleus and a scanty cytoplasm. The type 2 cell had a fairly rich cytoplasm with short cytoplasmic processes. The type 3 cell was characterized by a relatively large nucleus with sparse chromatin and well-developed cytoplasmic processes, and was considered a reactive astrocyte. The type 1 and some of the type 2 cells seemed to be neoplastic, displaying astrocytic differentiation. The remaining type 2 cells may have been reactive astrocytes. In one case of desmoplastic medulloblastoma, the majority of GFAP-positive cells were arranged in "islands", and had delicate fibrillated processes. GFAP-positive cells were also observed outside these "islands", though they were less numerous. Most of them were regarded as type 3 cells, but some were type 2. This may be interpreted as meaning that the glial character of the tumor was expressed more within than outside these "islands".

Expression of the Neurotrophin Receptor p75NTRin Medulloblastomas Is Correlated with Distinct Histological and Clinical Features: Evidence for a Medulloblastoma Subtype Derived from the External Granule Cell Layer

“…Evidence of neuronal differentiation has been presented by several authors, including expression of NSE, synaptophysin, and class III ß-tubulin (2)(3)(4)(5)7). In an important immunohistochemical study on this subject (18), Katsetos et al demonstrated the expression of the calcium-binding protein calbindin-D 28k (calD) in some VM cells and in Purkinje neurons.…”

“…Glial differentiation in PNET/MB, defined by the expression of GFAP, has been the subject of many studies (2,3,(7)(8)(9). Herpers and Budka (46) found expression of GFAP exclusively in DMBs.…”

Immunohistochemistry of retinoblastomas

“…The purified protein with Freund's complete adjuvant was injected weekly into New Zealand white rabbits intra-and subcutaneously for 4 weeks. The antisera were absorbed with the homogenates of KNS 42 cells, a permanent human glioma cell line rich in GFAP [7]. The monospecific reactivities of each antisera were confirmed by the immunoblotting method of Towbin et al [8].…”

“…The antibodies specifically reacted with axons and some neuronal perikarya in the normal human tissues by immunohistochemical methods. The antibodies against q/-enolase [9], GFAP [7] and S-100 protein [10] were reported. The monoclonal antibody of MBP was obtained commercially (Hybritec, USA).…”

Pigmented Primitive Neuroectodermal Tumor with Multipotential Differentiation in Cerebellum (Pigmented Medullomyoblastoma)

“…It has long been known that the common cerebellar tumor, customarily called 'medulloblastoma', com posed primarily of undifferentiated neuroepithelial cells, may also exhibit differentiation along one or more mature neuroectodermal cell lines such as glia or neu rons [3,4,16,20,22], A small fraction of tumors formed by these undifferentiated neuroepithelial cells may con tain smooth or striated muscle, in which instances they have been called medullomyoblastoma (see table I).…”