Differential spectrum of expression of neural cell adhesion molecule isoforms and L1 adhesion molecules on human neuroectodermal tumors.

A series of four medulloblastomas, seven neuroblastomas (Nb), two ependymomas, and three gliomas, human neuroectodermal tumors, were screened for their expression of adhesion molecules L1, carcinoembryonic antigen, neural cell adhesion molecule isoforms (N-CAM) and HNK1 epitope by Western blotting and double immunofluorescence labeling. All seven neuroblastomas, whatever their differentiated state, expressed L1, a neural cell surface developmental antigen, whereas all other tumors tested were negative. All tumors expressed N-CAM; however, a large diversity was observed among the isoforms. Low sialylated N-CAM 140 was present, with different intensity, in ependymomas and astrocytomas. High sialylated isoforms were detected by a monoclonal antibody (anti-MenB) specifically recognizing high polymers of alpha 2-8 linked neuraminic acid. They were expressed in all medulloblastomas studied (4 of 4), and in 4 of 7 Nbs examined. Negative cases corresponded to tumors having undergone chemotherapeutic treatment or to ganglioneuroma. The interconversion from high to low sialylated forms might reflect changes which are critical for the conversion of Nbs into benign ganglioneuromas. HNK1 epitope was expressed on a large diversity of molecules by nearly all tumors except two Nbs which were also negative with anti-MenB antibody. This simultaneous loss of carbohydrate epitopes could correlate with higher maturation states of the tumors. None of the tumors expressed carcinoembryonic antigen. Therefore, anti-L1 and anti-MenB antibodies define differentiation-related antigens that could differentiate between Nbs and other tumors and may prove helpful in diagnosis and understanding of the biological nature of neuroectodermal tumors. An immunodot assay was set up and allowed to titrate the presence of polysialic acid units in cerebrospinal fluid from patients presenting meningeal spread of medulloblastomas. It could help to assess metastasis and to monitor the effects of chemotherapeutic treatment on polysialylated N-CAM positive tumors.

Sex steroids in human brain tumors and breast cancer.

The concentrations of three sex steroids, estradiol, progesterone and testosterone, were analyzed by radioimmunoassay after celite chromatography in brain tumor and breast cancer tissues. The concentrations in malignant gliomas and breast cancers showed interindividual variations, especially evident with regard to estradiol. High estradiol concentrations were recorded in two patients with malignant astrocytoma. The concentrations of 1.00 pg/mg and 3.32 pg/mg were 10 to 30 times as high as in normal female brain. In five of ten astrocytomas the estradiol concentration was higher than the lowest breast cancer value. The distribution of progesterone seemed more even, and the level was significantly lower in brain tumors and breast cancers as compared with female brain, perhaps indicating an increased metabolism. Testosterone levels were somewhat higher in brain tumors, as compared with breast cancers, but not different from values in brain tissue. There were no significant age or sex correlation or differences in the concentrations of steroids in the brain tumors. The results suggest that manipulation of sex steroid metabolism in malignant brain tumors can be of beneficial therapeutic value as has been shown for breast cancer and prostatic carcinoma.

Molecular markers of primitive neuroectodermal tumors and other pediatric central nervous system tumors. Monoclonal antibodies to neuronal and glial antigens distinguish subsets of primitive neuroectodermal tumors.

Seventy-one tumors of the central nervous system in children were studied immunohistologically. Thirty-seven were classified histologically as PNETs, of which 35 were located in the cerebellum (medulloblastomas), one in the cerebrum, and one in the spinal cord. The 34 non-PNETs included five ependymomas, seven gangliogliomas, 15 astrocytomas, and seven tumors of other histology. We used monoclonal antibodies specific for neurofilament (NF) triplet proteins, for microtubule associated protein 2 and tau protein and for glial fibrillary acidic protein (GFAP) and myelin basic protein. In addition, a monoclonal antibody to epithelial membrane antigen was applied. The presence or absence of these antigens defined four major groups of PNETs: 1) PNETs not otherwise specified (10 cases), 2) PNETs with neuronal differentiation (eight cases), 3) PNETs with astrocytic differentiation (six cases), and 4) PNETs with both neuronal and astrocytic differentiation (12 cases). One case showed ependymal differentiation. The pattern of expression of NF isoforms in PNETs was reminiscent of that seen during normal mammalian development, such that phosphorylated NF-H was only present in combination with NF-M and NF-L. Among the other central nervous system tumors, all astrocytomas and gangliogliomas were positive for GFAP, and the gangliogliomas also expressed all NF isoforms. Three atypical teratoid tumors and two rhabdoid tumors showed strong positivity for epithelial membrane antigen and also for GFAP. We conclude that the differentiation antigens described here serve to distinguish PNETs from other pediatric central nervous system tumors and to identify subsets of PNETs. Accordingly, PNETs represent a heterogeneous group of pediatric brain tumors capable of neuronal and glial differentiation.

Ependymoma of the ovary. A clinico-pathologic, ultrastructural and immunohistochemical investigation. A case report.

A case of primary malignant ovarian ependymoma is described. The course of the tumor disease was extremely prolonged with a 50 year history. The diagnosis is supported by immunohistochemical and ultrastructural evidence of ependymal differentiation. The histogenesis and the origin from a possible preexisting ovarian teratoma are discussed.

[A case of large malignant choroid plexus papilloma in the third ventricle--immunohistochemical and ultrastructural studies].

A case of malignant choroid plexus papilloma (choroid plexus carcinoma) originated in the third ventricle is reported. A 14-month old girl was admitted to our department with two-month history of impaired vision and gait disturbance. Neurological examination on admission disclosed a lethargy, blindness, and left hemiparesis. Computed tomographic (CT) scan and magnetic resonance imaging (MRI) demonstrated a large contrast-enhancing mass, approximately 5 cm in diameter, in the region of third ventricle, extending to the bilateral lateral ventricles. The patient had gross total removal of the tumor via lateral ventricle route, and received 40 Gy of postoperative radiation therapy. Light microscopically, the tumor was composed of epithelial cells showing both papillary and poorly differentiated pattern. There were considerable cellular pleomorphism, frequent mitoses, and occasional necroses. Immunohistochemically, anti-keratin antibody was detected within majority of neoplastic cells. Both neoplastic epithelial cells and stroma showed negative reaction to anti-GFAP antibody. Ultrastructurally, the shape of the nuclei varied from ovale to irregular with many indentations. The chromatin was clumped around the periphery of the nuclei. The neoplastic cells contained numerous free ribosomes, glycogen granules, and rough endoplasmic reticulum. The apical cell surfaces showed various size of club-like or roundish microvilli filled with glycogen granules, and rarely 9 + 2 cilia. Elongated junctional complexes were occasionally seen near the apical ends. The basal portions of the cells had a continuous basement membrane. These immunohistochemical and ultrastructural findings were comparable to the choroid plexus papilloma with malignant features.(ABSTRACT TRUNCATED AT 250 WORDS)

Calmodulin content in human central nervous system tumors.

Benign and malignant brain tumors and normal cerebral cortex were assayed for calmodulin content by enzymatic and radioimmunoassay techniques. Normal cerebral cortex contained more (8.31 +/- 1.27 vs 3.30 +/- 0.42 micrograms/mg protein) calmodulin than the brain tumors. The contents of calmodulin in the malignant glioblastomas were significantly higher than the meningiomas (5.41 +/- 0.31 vs 2.97 +/- 0.16 micrograms/mg protein). These differences were independent of tumor location and persisted when calmodulin content was normalized for DNA rather than protein content. This data supports differences in the tissue calmodulin contents with normal cortex greater than primary malignant tumors greater than benign tumors greater than metastatic tumor tissue.

[Expression of insulin-like growth factor I receptors in human brain tumors: comparison with epidermal growth factor receptor by using quantitative autoradiography].

By using quantitative autoradiographic techniques, receptors for insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) were analyzed in 13 samples of human brain tumors (4 low grade astrocytomas, 7 glioblastomas, 1 anaplastic ependymoma and 1 medulloblastoma). High number of specific binding sites for IGF-I and EGF were homogeneously present in tissue sections derived from glioblastoma. In low grade astrocytoma, relatively high numbers of binding site for EGF were observed, but there was no significant difference in concentrations of IGF-I binding sites between tumors and control cortex. In medulloblastoma, only IGF-I binding sites were present. These observations might indicate that both IGF-I and EGF are involved in the growth modulation of human gliomas possibly through paracrine or autocrine mechanisms. Antagonists to growth factors or monoclonal antibody against those receptors could have the way for therapeutic application for gliomas.

Mapping of receptors for carbohydrate constituents of glycoconjugates in well-differentiated and malignant ependymomas: a glycohistochemical study.

Recognitive interactions between the carbohydrate part of cellular glycoconjugates and endogenous receptors supposedly govern important biological processes. Consequently, their elucidation can be of considerable value in tumour diagnosis. The histochemical patterns of expression of endogenous sugar receptors (e.g. endogenous lectin-like proteins) of 10 cases of well-differentiated ependymoma and 10 cases of malignant ependymoma were analysed, using a panel of 18 biotinylated (neo)glycoproteins and a standardized staining protocol. Within this panel, differences in the extent of staining for intracellular sugar receptors in well-differentiated and malignant ependymomas were histochemically detectable. In comparison to the well-differentiated ependymomas, the anaplastic form of the tumour exhibited a generally higher capacity to specifically bind labelled (neo)glycoproteins, containing alpha- or beta-glucosides and a disaccharide, characteristic for one type of beta-galactoside-terminated chain structure of glycoproteins. A significantly reduced binding was seen for tumours of the anaplastic type with labelled markers, carrying histochemically indispensable glucuronic acid residues. These findings suggest that labelled neoglycoproteins are a valuable tool for assessing the endogenous sugar-binding capacity in diagnostic histopathology. Our descriptive analysis of endogenous sugar receptors may also be a rational basis for studies on the functional significance of changes in the expression of their endogenous ligands and the cellular glycoconjugates. Further investigations are also possible on the correlation between the degree of differentiation and expression of both parts of a recognitive system, based on protein (receptor)-carbohydrate (ligand) interactions, in tumours of the central nervous system, especially ependymomas.

[Immunohistochemical study on distribution of transthyretin in normal human brain tissue and tumors].

Immunohistochemical examination of transthyretin (TTR), which is known to be synthesized in the epithelial cells of the choroid plexus as well as in the liver cells, was carried out on normal brain tissues and 84 human brain tumors, using a peroxidase-antiperoxidase (PAP) technique. TTR was demonstrated diffusely and strongly in the cytoplasm of normal choroid plexus cells, but not in ependyma and other tissues of normal brain. In all of 10 choroid plexus papillomas, TTR was found within the cytoplasm of tumor cells. In contrast, neither the two papillary ependymomas nor any other brain tumors contained TTR. Among the choroid plexus papillomas, some cases showed clear positive reactions in almost all tumor cells, while others had only a few TTR-positive cells. With these immunohistochemical findings, TTR proved a very useful marker of normal choroid plexus and choroid plexus papilloma.

[Congenital ependymoma. Case report and immunohistochemical studies]. / Kongenitales Ependymom. Fallmitteilung sowie immunhistochemische Untersuchungen.

Reported in this paper is a congenital ependymoma in an 23-week old foetus. The neoplasm was well vascularised and contained typical ependymal rosettes. The tumour cells did not react with GFAP-antiserum. They reacted weakly with neuron-specific enolase and vimentin and exhibited strong antigenicity with S-100-protein-antiserum. Cytokeratin antigen was recordable from some tumour cells. The tumour was sufficiently mature for classification as ependymoma. Immunohistochemical findings suggested possible ectodermal origin of the tumour cells.

A histologic and immunocytochemical study of choroid plexus tumors of the dog.

Sixteen choroid plexus (CP) tumors in 12 male and four female adult dogs were analyzed microscopically. Tumors were in the lateral (six), third (six), and fourth (four) ventricles. The average age of the dogs was 6 years. Tumors were classified by the following criteria: 1) choroid plexus papilloma (CPP), which resembled normal choroid plexus and had low mitotic activity; 2) choroid plexus papilloma (CPP), which resembled normal choroid plexus and had low mitotic activity; 2) choroid plexus papilloma with atypical features (atypical CPP), which had increased cellular density, nuclear atypia, two to four mitoses per 40x microscopic field, necrosis, and infiltration of the brain parenchyma and/or leptomeninges; and 3) choroid plexus carcinoma (CPC), which had marked nuclear atypia, poorly formed papillae, greater than four mitoses per 40x microscopic field, abnormal mitotic figures, and/or extraneural metastasis. The 16 tumors were classified either as CPP or atypical CPP (none as CPC). Statistically significant associations between brain infiltration and necrosis and atypical CPP were identified. Immunohistochemical studies in 11 tumors demonstrated staining for keratin in three tumors, two of which also reacted with carcinoembryonic antigen (CEA). There was no immunoreactivity with glial fibrillary acidic protein or epithelial membrane antigen. Choroid plexus from one of three control dogs stained focally for cytokeratin only. It is concluded that normal choroid plexus and CP tumors in the dog express epithelial, but not glial differentiation.

[A simple method for the isolation of GFAP and its use for the study of brain tumors]. / Eine einfache Methode zur Isolierung von GFAP und ihre Anwendung zur Untersuchung von Hirntumoren.

A simple method is described in this paper for the production of a polyclonal antiserum against GFAP. The antiserum was tested on 212 primary brain tumours which had been selected from biopsy and autopsy material of the Institute of Pathological Anatomy at the Medical Academy of Erfurt, GDR. 52 of 81 astrocytomas (64%) and 26 of 47 glioblastomas (55%) gave GFAP-positive results. GFAP-negative responses were primarily recorded from tumours with severe anaplasia. GFAP was found in all 22 ependymomas tested. Epithelioid ependymomas, however, exhibited lower immunological reactions than tanycytic variants. Isomorphic oligodendrogliomas, meningiomas, medulloblastomas, and brain metastases of carcinomas were GFAP-negative. The possibility is discussed in some detail of falsely negative results on account of too little biopsy material or insufficient fixation of tumour tissue.

Rosenthal fibres are based on the ubiquitination of glial filaments.

Immunocytochemical localization of the cell stress-associated protein ubiquitin was performed on human lesions containing Rosenthal fibres. Ubiquitin was localized around the periphery of classical Rosenthal fibres but not in the amorphous central areas; the ubiquitin-positive regions corresponded to the immunocytochemical localization of glial fibrillary acidic protein (GFAP). Compact bundles of GFAP in glial processes without a non-staining core were also associated with ubiquitin, while loosely aggregated cellular GFAP was not. The relationship between compact bundles of GFAP and the amorphous osmiophilic central component of Rosenthal fibres has been uncertain. These data, however, show that the compact bundles of glial filaments are distinct from normal GFAP in being associated with ubiquitin. A role for ubiquitin in Rosenthal fibre formation is suggested. We propose that the term Rosenthal fibre be restricted to mean the hyaline amorphous core of these structures, while realizing that this is based on a wider abnormality of surrounding glial fibrillary acidic protein filaments.

[Intracranial ependymoma with extraneural metastases]. / Intrakranielles Ependymom mit extraneuralen Metastasen.

A report is given on a 14-year-old boy with an ependymoma of the brain which was 3 times operated upon. At autopsy, a widespread leptomeningeal and intraventricular dissemination was found. Extraneural metastases developed in the soft tissues of the neck as well as in the pleura and lung on the left side. Immunohistochemically, the cells of the brain tumor and extraneural metastases of the neck showed a positive GFAP-reaction. According to Tables 17 to 19 of Jänisch and co-workers (1976; 1988) and Table 1 of this paper, 48 intracranial, intraspinal and ectopic (subcutaneous sacrococcygeal) ependymomas with extraneural metastases were collected from the literature.

Estrogen and progestin receptors in an ovarian ependymoma.

Ovarian neoplasms of the pure neuroectodermal type, although quite rare, have recently been described. Lesions of similar histology in the central nervous system have previously been shown to contain estrogen and progestin receptors. A patient with a pure ovarian ependymoma is presented. The tissue was rich in estrogen and progestin receptor protein, containing 17 femtomoles of estrogen receptor per milligram cytosol protein and 80 femtomoles of progestin receptor per milligram cytosol protein. The case is used to illustrate the possible influence of hormonal manipulation in the management of this rare gynecologic neoplasm.

Immunocytochemical analysis of intermediate filaments in human ependymal tumors.

The peroxidase anti-peroxidase technique was used for localization of glial fibrillary acidic protein (GFAP) and vimentin (VM) in 19 ependymal tumors in order to determine if a unique pattern of intermediate filament (IF) expression could be demonstrated. Cytokeratin (CK) immunoreactivity was examined in a subgroup of 7 tumors with papillary pattern. Nineteen non-ependymal neuroectodermal tumors were used as controls. Ependymomas, subependymomas and astrocytomas were positive for both IF. Oligodendrogliomas, oligodendroglial portions of mixed gliomas and the majority of medulloblastomas were negative for GFAP and VM. Areas of poor differentiation in all tumors demonstrated little expression of any IF. A composite ependymoma/choroid plexus papilloma showed the presence of GFAP, VM and CK in the papillomatous portion only. Four papillary ependymomas were negative for CK. This study emphasizes the parallel distribution of GFAP and VM in well differentiated ependymomas and other glial tumors and casts doubt upon the concept of VM as a marker for de-differentiation in neuroectodermal neoplasia.

Epithelial membrane antigen expression in ependymomas.

Twenty-seven ependymomas were studied (18 'benign' or low grade and nine 'malignant' or high grade) by means of a monoclonal antibody to epithelial membrane antigen (E29) and an antiserum to glial fibrillary acidic protein (GFAP). The E29 antibody reacted with 'benign' ependymomas but not with 'malignant' ones. Staining was located on the cell surface and especially that facing rosette lumina. Cells forming papillary structures and ependymal epithelium showed a similar distribution of staining. Glial fibrillary acidic protein (GFAP) reactivity was seen in all tumours, with a perivascular accentuation in 'malignant' ones. Staining occurred in the cytoplasm of scattered cells and in those forming papillary structures, ependymal epithelium and rosettes. Our results may have implications in relation to the cytogenesis of these tumours and may also be useful in the histological assessment of 'benign' versus 'malignant' ependymomas.

Ependymal and choroid plexus tumors. Cytokeratin and GFAP expression.

Twenty-six ependymal and 15 choroid plexus tumors were examined with monoclonal antibody against cytokeratin using the avidin-biotin-peroxidase complex (ABC) technique. Serial sections were examined with antisera to glial fibrillary acidic protein (GFAP). In five ependymal tumors (one ependymoma, two papillary ependymomas, and two primitive neuroectodermal tumors [PNET] with ependymal cells), a variable number of cytokeratin-positive cells were present. Most tumor cells (except two PNET) were positive with GFAP antisera. Many cytokeratin-positive cells were present in all choroid plexus tumors. GFAP-positive cells were present focally in six of 11 papillomas and in one of four carcinomas. Although their staining patterns and distribution were clearly different, focal coexistence of cytokeratin and GFAP was observed in six papillomas and two ependymal tumors. Thus, some ependymal tumors (especially papillary ependymomas and occasional PNET) and many choroid plexus tumors have demonstrable positivity with antibody to cytokeratin, suggesting a transitional cell type with features of both ependyma and choroid plexus.

Immunocytochemical demonstration of glial fibrillary acidic protein in imprint smears of human brain tumors.

Papanicolaou-destained imprint smears from 24 brain tumors were investigated by means of avidin-biotin-peroxidase complex method (ABC) with the use of monoclonal antibodies against glial fibrillary acidic protein (GFAP). Positive staining reaction to GFAP antibody has been demonstrated in cells from the following tumors: astrocytoma, anaplastic astrocytoma, glioblastoma multiforme, mixed glioma, and ependymoma. The reaction for GFAP was negative for the following tumors: medulloblastoma, neurilemmoma, melanoma, hemangioblastoma, and metastatic tumors. In astrocytoma, the cell bodies and processes were positive with delicate fibrillary patterns; in anaplastic astrocytoma, cytoplasm and the processes were intensively stained. In glioblastoma multiforme, the staining patterns were also mixed, and the short, thickened processes were characteristic. Use of both a smear preparation and the immunoperoxidase staining technique is of great value in diagnosis of tumors of the central nervous system.

Ependymoma of the mediastinum.

A case of primary ependymoma of the mediastinum is reported. The tumor was adherent to the lung and metastasized to adjacent mediastinal lymph nodes. An autopsy showed no evidence of tumor in the central nervous system. The diagnosis of ependymoma was confirmed by the immunohistochemical positivity for glialfibrillary acidic protein. To the best of our knowledge, this is the first reported example of an ependymoma in this location.