SEARCH · PubMed Health

Results for “neuroectoderm”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed1992

Expression of Pax-3- and neuroectoderm-inducing activities during differentiation of P19 embryonal carcinoma cells.

A P19 embryonal carcinoma stem cell line carrying an insertion of the E. coli LacZ gene in an endogenous copy of the Pax-3 gene was identified. Expression of the Pax-3/LacZ fusion gene in neuroectodermal and mesodermal lineages following induction of differentiation by chemical treatments (retinoic acid and dimethylsulfoxide) was characterized using this line and is consistent with the previous localization of Pax-3 expression in the embryo to mitotically active cells of the dorsal neuroectoderm and the adjacent segmented dermomyotome. Pax-3/LacZ marked stem cells were also utilized as target cells in mixing experiments with unmarked P19 cells that had been differentiated by pretreatment with chemical inducers. Induction of beta-galactosidase and neuroectodermal markers in the target cells demonstrates that: (1) some differentiated P19 cell derivatives transiently express endogenous Pax-3- and neuroectoderm-inducing activities, (2) undifferentiated target stem cells respond to these activities even in the presence of leukemia inhibitory factor and (3) the endogenous activities can be distinguished from, and are more potent than, retinoic acid treatment in inducing neuroectoderm. These observations demonstrate that P19 embryonal carcinoma cells provide a useful in vitro system for analysis of the cellular interactions responsible for neuroectoderm induction in mammals.

Animals↗

PubMed1979

Immunoelectrophoresis in the diagnosis of neuroectodermal and mesodermal intracranial tumours, especially those of the posterior fossa.

Immunoelectrophoresis of extracts of 200 intracranial tumours against rabbit anti-glioblastoma serum gave positive results (= precipitation) in all cases of tumours of neuroectodermal origin such as glioblastoma, astrocytoma, oligodendroglioma, ependymoma, neurinoma, and spongioblastoma. No immunoelectrophoretic precipitation was seen for any of the tumours of mesenchymal origin, for instance meningioma and metastases of cancer. On the basis of these findings, immunoelectrophoresis is considered to be a reliable method for differentiation between tumour tissue of neuroectodermal and non-neuroectodermal origin. Among the 41 posterior fossa tumours some unusual observations were made. Cerebellar angioblastoma (Lindau tumour) showed an atypically located precipitation line, which for the present is interpreted as an immunological reaction to vascular wall tissue. Furthermore, among the group of so-called medulloblastomas, two subgroups were distinguished on the basis of three parameters. The first of these subgroups comprises tumours whose immunoelectrophoretic pattern resembles that of gliomas, which are histologically characterized by neuroectodermal structures and which occur in younger children (5--10 years). The tumours of the second subgroup, which do not show this neuroectodermal immunoelectrophoretic pattern, have a sarcomatous character histologically, and occur in patients aged between 10 and 50 years. The view that medulloblastoma comprises a number of different types of tumour seems to be confirmed by this finding.

Animals↗

PubMed1976

Simultaneous occurrence of melanotic neuroectodermal tumor and brain heterotopia in the oropharynx.

A case is described of heterotopic brain tissue with simultaneous occurrence of melanotic neuroectodermal tumor in the oropharynx of a 6-week-old infant. The melanotic neuroectodermal tumor was embedded within the heterotopic glial tissue. This coexistence leads us to speculate that a defect causing a pinching-off of both neural crest cap and medullary epithelium of neural tube might have taken place at, or before, the 25-30 somite stage. The displaced embryonic structures subsequently differentiated into glial tissue, choroid plexus, and melanotic neuroectodermal tumor. This observation may be interpreted as further support in favor of a neural crest origin of juvenile melanotic neuroectodermal tumor.

Brain↗

PubMedDate not supplied

Melanotic neuroectodermal tumors of the brain and skull.

A case of melanotic neuroectodermal tumor in the cerebellum of a 21-year-old man is presented. Melanin was found mainly in small neoplastic cells rather than in large epithelioid cells. The tumor also contained neurons, as well as neoplastic tissue of ependyma, choroid plexus; and astrocytes. We propose that this neuroectodermal tumor resulted from a combination of cells originating in the neural crest and in the neural tube. The small cells have been described as medulloblasts, but they may be poorly differentiated ependymal cells, or, sympathicoblasts. The presence of pigment in these cells is compatible with an origin in the neural crest. The so-called melanotic progonoma, occurring most often in the maxilla of infants, is reviewed in relation to the melanotic neuroectodermal tumor of the brain. The tumor in facial bone occurs in adults as well as infants, in locations other than the maxilla, and has malignant forms. Melanotic neuroectodermal tumors, whether in brain or bone, are therefore similar in behavior as well as histologic appearance. The finding of similar tumors in these different locations is readily explained embryologically.

Adult↗

PubMed1992

Peripheral primitive neuroectodermal tumors. A flow cytometric analysis with immunohistochemical and ultrastructural observations.

Flow cytometry of classical neuroblastoma has provided provocative evidence that cell cycle and ploidy analysis generate prognostically useful information. To determine whether such analyses of peripheral primitive neuroectodermal tumors might yield similar results, formalin-fixed, paraffin-embedded tissue specimens from 19 peripheral primitive neuroectodermal tumors, each previously characterized by immunohistochemical or ultrastructural study, were assessed. An acceptable histogram was obtained in 16 cases. Of these, nine neoplasms were diploid and seven contained aneuploid DNA. Among patients with diploid lesions, four were free of disease, whereas three had persistent or recurrent disease, and two had died of tumor. Among patients with aneuploid neoplasms, four were free of disease, one had recurrence, and two had died. There was no apparent correlation between immunophenotype and proliferative activity with the clinical outcome. Among aneuploid peripheral primitive neuroectodermal tumors, DNA index did not predict survival. Hence, cell cycle and DNA ploidy analyses do not appear to contribute to the prognostic assessment of peripheral primitive neuroectodermal tumors, as they do to presumably related neoplasms of the central and peripheral nervous system.

Aneuploidy↗

PubMed1976

Histochemistry of oxidoreductases, enzymatic polymorphism and anaplasia of neuroectodermal tumors.

Oxidoreductases were studied histochemically in 162 cases of neuroectodermal tumors. In order of decreasing activity in the cytoplasma these enzymes could be arranged as follows: NADH diaphorase, lactate dehydrogenase, NADPH diaphorase, glutamate dehydrogenase, glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase, malate dehydrogenase. The weak activity of Krebs cycle enzymes and the relatively strong activity of other oxidoreductases, particularly of lactate dehydrogenase, permits to conclude that glycolysis prevails over oxidative processes in neuroectodermal tumor cells. But this should not be interpreted as a decrease of the Krebs cycle enzymes in astrocytoma and oligodendroglioma cells as compared with their parent cells because the latter themselves display a weak activity of these enzymes. A real decrease of Krebs cycle enzyme activity was established only for tumors, the parent cells of which are characterized by a strong (in choroid-papillomas) or moderate (in ependymomas) activity of these enzymes. Many neuroectodermal tumors, in particular those of astrocytic origin, demonstrate a certain correlation between the amount of cytoplasm and oxidoreductase activity. This results in enzymatic polymorphism of the tumor tissue. A certain similarity was established of the oxidoreductase activity in tumor cells and in reactive hypertophic astrocytes. This indicates that both tumor cells and reactive astrocytes may in certain conditions utilize similar mechanisms of increased metabolism. The oxidoreductase activity correlates not with the grade of anaplasia but with different directions of anaplasia reflected in different variants of neuroectodermal tumors. The concept "anaplasia" includes not only certain degrees of dedifferentiation of tumor cells but, as it has been shown histochemically, also an increase of metabolic processes in the tumor cell cytoplasma.

Anaplasia↗

PubMed1977

Melanotic neuroectodermal tumor of infancy: its histological similarities to fetal pineal gland.

Striking similarities between the pineals of 107 fetuses and infants and a pigmented neuroectodermal tumor occurring in the right orbital and right frontal regions in a 6-month-old Puerto Rican boy were found. Both the human fetal pineal and melanotic neuroectodermal tumors of infancy are characterized by pigmented (melanin) epithelial cells, small undifferentiated cells, and a fibrovascular stroma. Our findings suggest the fetal pineal may be a normally occurring precursor of the melanotic neuroectodermal tumor of infancy, or that melanin production may be a normal capability of differentiating neuroepithelial cells.

Child, Preschool↗

PubMed1979

Malignant melanotic neuroectodermal tumor of infancy: a clinical, pathologic, ultrastructural and tissue culture study.

The melanotic neuroectodermal tumor of infancy is an uncommon neoplasm typically of early childhood which has a predilection for the head and neck region, particularly the maxilla. Except for one previous example in the literature, this tumor has consistently behaved in a benign fashion. This study documents the clinical course and pathologic findings of a tumor which began in the maxilla of a 4-month-old boy, followed by a local recurrence, metastasis to a cervical lymph node and finally, widespread dissemination and death at 18 months, 24 months and 38 months, respectively. The tumor was initially composed of nests consisting of melanin-containing cells and small dark cells. An elevated vanillylmandelic acid level was recorded during the course of the disease. At autopsy, the tumor in lymph nodes, liver, bone and soft tissues had a monotonous pattern of small dark cells similar to a conventional neuroblastoma. Previous ultrastructural studies indicate that the melanotic neuroectodermal tumor of infancy is composed of melanocytes and neuroblast-like cells. Our case provided the unique opportunity to examine in sequence the ultrastructural and in vitro characteristics of a recurring and eventually metastasizing melanotic neuroectodermal tumor. Although the neuroblast-like cells were initially difficult to identify by electron microscopy, a melanin-producing cell line and a separate nonpigmented cell line were successfully isolated from various tumor explants. Various stages of melanosome development were identified in the pigmented cells from the local recurrences and in vitro. Dibutyryl cAMP accentuated the formation of pigment and dendritic development in the melanocytes and dendrites only in the small nonpigmented cells. Electron dense granules were observed in the cultured smaller cells and also in the lymph node and soft tissue metastases. Tyrosine hydroxylase activity was demonstrated in the neuroblast-like cells. In the final biopsy and autopsy material, only the neuroblast-like cells remained and the tumor resembled a conventional neuroblastoma.

Culture Techniques↗

PubMed1992

Development of multidrug resistance in a primitive neuroectodermal tumor cell line.

Drug resistance remains a formidable obstacle to the successful treatment of pediatric primitive neuroectodermal tumors. Resistance to chemotherapeutic agents may be related, in part, to expression of the multidrug resistance gene 1 (MDR1). The protein product of this gene, P-glycoprotein, confers resistance to multiple unrelated antineoplastic drugs. The cell line DAOY, derived from a primitive neuroectodermal tumor, was used as an in vitro model to examine the development of drug resistance. Cell lines resistant to actinomycin D were developed by the growth of DAOY in increasing concentrations of the drug. The IC50 (concentration of drug needed to induce a 50% reduction in cell growth) of the resultant lines to actinomycin D was more than 10 times that of the parental line. The resistant lines were cross-resistant to VP-16 (etoposide), despite lack of previous exposure to this drug. The resistance to actinomycin D was attenuated in the presence of verapamil, a known inhibitor of P-glycoprotein. The MDR1 gene was not expressed by the parental DAOY line at the messenger ribonucleic acid (RNA) and protein level. Expression of the MDR1 gene was documented in the resistant lines by RNA blot and immunoblot techniques. These results suggest that exposure to chemotherapeutic drugs can induce classical multidrug resistance in primitive neuroectodermal tumors.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1992

Sinonasal primitive neuroectodermal tumor arising in a long-term survivor of heritable unilateral retinoblastoma.

BACKGROUND: Patients who survive retinoblastoma (RB) are at risk for having second nonocular tumors, usually osteosarcomas, which often are fatal. Such patients almost always have bilateral RB. METHODS: This article reports a woman who, at the age of 1 year had been cured of a unilateral RB by radiation therapy and enucleation. Eighteen years later, she had a sinonasal small cell tumor that rapidly recurred and proved fatal 2 months after surgical debulking. The tumor was studied by immunohistochemistry and electron microscopic (EM) examination. RESULTS: It showed diffuse neuron-specific enolase staining, focal weak staining for chromogranin, synaptophysin, and Leu-7 monoclonal antibodies in paraffin-embedded, B5-fixed tissue (Great Lakes Diagnostics, Troy, MI). EM study showed an undifferentiated primitive neuroectodermal tumor with many polyribosomes, simple cell junctions, few microtubules, and rare dense core granules. CONCLUSIONS: The combined immunohistochemical, ultrastructural, and clinical features of the tumor were interpreted as a sinonasal primitive neuroectodermal tumor with early neuronal differentiation. The tumor was pathologically indistinguishable from poorly differentiated olfactory neuroblastoma (ONB) and Ewing sarcoma.

Chromogranins↗

PubMed1979

Primitive neuroectodermal tumor (neuroepithelioma) of spinal nerve root -- Report of an adult case and establishment of a cell line.

A case of primitive neuroectodermal tumor arising in the cervical nerve root of a 28-year-old man is presented. Histologically, the tumor was characterised by proliferation of primitive neuroectodermal cells and formation of numerous Homer-Wright type rosettes. A cell line (Nagai line) was established from the tumor. Electron microscopic examination of Nagai cells revealed numerous microrosette formation with microvilli-like cytoplasmic processes projecting into the central lumina. Neurosecretory granules appeared in the cytoplasmic processes when Nagai cells were treated with dibutyryl cyclic AMP. Primitive satellite cells which completely surrounded other tumor cells with their tongue-like slender cytoplasmic processes were also found. Histogenesis of this unique tumor was discussed comparing with the neuroblastoma of sympathetic nervous system, medulloblastoma of the central nervous system, and with the tumors induced by Adenovirus type 12 in animals. It was concluded that the tumor was neuroepithelioma derived from a primitive stem cell of neural crest origin which possesses the bipotency to differentiate toward either neuroblastic or neurilemmal line.

Adult↗

PubMed1992

Secretogranin II expression in Ewing's sarcomas and primitive neuroectodermal tumors.

Production of chromogranins, the acidic components of the chromaffin granules regarded as specific neuroendocrine markers, was analyzed by immunocytochemistry and hybridization (Northern blotting and in situ hybridization) in primary lesions and cell lines of Ewing's sarcomas, primitive neuroectodermal tumors (PNETs), and neuroblastomas. Antibodies and probes specific for chromogranin A (CgA), chromogranin B (CgB), and secretogranin II (SgII) were used. Ewing's sarcomas and PNETs, unlike neuroblastomas, were negative for CgA and CgB. Two primary Ewing's sarcomas, one primary PNET (an Askin tumor), and one PNET cell line (TC32) were found to strongly express the SgII gene, as shown by the presence of specific mRNA. This result supports the hypothesis that some Ewing's sarcomas represent a most primitive form of neuroectodermal tumor; in addition, it indicates a diagnostic role of SgII in cases of Ewing's sarcomas and PNETs.

Adolescent↗

PubMed1992

Familial syndrome of endocrine and neuroectodermal abnormalities.

We report on a previously undescribed combination of endocrine and neuroectodermal abnormalities in four sibs from Burma. These abnormalities include low growth hormone levels in response to provocative stimuli, delayed puberty associated with prepubertal levels of gonadotropins in the males and pubertal levels of gonadotropins in the females, type II diabetes mellitus with elevated insulin levels, mild mental retardation, sensori-neural deafness, and alopecia without pili torti. They also had a characteristic facial appearance and fleshy hands and feet. This family appears to have a previously undescribed combination of endocrine and neuroectodermal abnormalities.

Adolescent↗

PubMed1992

A continuous cell line (KK-2) from a supratentorial primitive neuroectodermal tumor.

Tumor tissue located in the occipital lobe with hemorrhage was obtained from a 19-year-old patient. Histological examination indicated it to consist of undifferentiated small, round cells without neuronal or glial differentiation, and possibly to be a type of primitive neuroectodermal tumor. The tumor cells were cultured for 3 years and a continuous cell line (KK-2) was established. KK-2 was transplantable to nude mice. With immunocytochemistry, neuron-specific enolase, protein gene product 9.5, vimentin, TUJ1 (a monoclonal antibody specific for neuron-associated class III beta-tubulin isotype) and 6H7 (a monoclonal antibody to NCAM produced by us) were detected. None of the following could be found: glial fibrillary acidic protein, S-100 protein, neurofilament and synaptophysin, calcitonin gene-related peptide, gastrin releasing peptide corticotropin-releasing factor, substance P, somatostatin, chromogranin, aromatic L-amino acid decarboxylase and tyrosine hydroxylase. The original tumor and KK-2 cells obtained after 3 years of culture and transplants in nude mice displayed essentially the same ultrastructural and immunohistochemical characteristics. KK-2 cells showed no differentiation to mature neuronal, glial or ependymal cells. This cell line may possibly serve as a useful model for studying cellular differentiation of human neuroectodermal tumors and normal neuronal development.

Adult↗

PubMed1978

Mixed mesenchymal and neuroectodermal tumor of the cerebellum.

An unusual cerebellar tumor composed of mixed mesenchymal and neuroectodermal elements in a 44 year old man is reported. The mesenchymal element is well-differentiated adipose tissue, whereas the neuroectodermal components exhibit a variety of medulloblastomatous, astrocytomatous, oligodendrogliomatous and ependymomatous areas. A possible origin of such unusual mixed neoplasms is briefly discussed.

Adipose Tissue↗

PubMed1976

Sequential adsorption analysis of antibodies to neuroectodermal cells by an indirect quantitative method.

An indirect radioimmunoassay was developed for the sequential adsorption analysis of rabbit antibodies raised against rat neuroectodermal cells. The quantitativee relationship between primary adsorbed rabbit antitumor antibodies and secondary adsorbed goat antibodies to rabbit IgG was explored by paired radioiodine analysis. In the final indirect method, the amount of unlabeled rabbit antibody removed by cultured monolayers of cells at each step in a sequence of cells could be determined from an equation relating the unlabeled amount to values of bound 125I-labeled goat antirabbit IgG. To obtain the total quantity of rabbit antibody in a particular antiserum reagent, a sequential adsorption analysis was done with successive steps of homologous cells. To obtain the amount of antibody that was cross-reactive for other cell lines, we included those lines in the first several steps of the sequence. The sequential adsorption profile was considered as a more important indicator of the quality of a particular antiserum reagent than was the total amount of antibody contained in it. Neuroectodermal cell lines used as illustrative examples included subclones of the C6 astrocytoma and of the RN-2 schwannoma.

Animals↗

PubMed1992

Melanotic neuroectodermal tumor of infancy. A case report of paratesticular primary with lymph node involvement.

A 17-month-old boy had a melanotic neuroectodermal tumor of infancy in the left paratesticular region affecting the retroperitoneal lymph nodes. Immunohistochemical and ultrastructural study showed phenotypical diversity of the proliferating cells within a spectrum of neuroectodermal differentiation. Urinary catecholamine levels were initially elevated but returned to normal values after complete eradication of the tumor. The patient received chemotherapy and is now well, without evidence of disease 28 months after surgery.

Biomarkers, Tumor↗

PubMed1992

The dorsal gradient morphogen regulates stripes of rhomboid expression in the presumptive neuroectoderm of the Drosophila embryo.

rhomboid (rho) encodes a putative transmembrane receptor that is required for the differentiation of the ventral epidermis. It is initially expressed before the completion of cellularization in lateral stripes within the presumptive neuroectoderm. Here, we present evidence that the maternal morphogen dorsal (dl) acts in concert with basic helix-loop-helix (b-HLH) proteins, possibly including twist (twi), to activate rho in both lateral and ventral regions. Expression is blocked in ventral regions (the presumptive mesoderm) by snail (sna), which is also a direct target of the dl morphogen. A 300-bp region of the rho promoter (the NEE), which is sufficient for neuroectoderm expression, contains a cluster of dl and b-HLH activator sites that are closely linked to sna repressor sites. Mutations in these binding sites cause genetically predicted changes in the levels and limits of rho expression. In particular, the disruption of sna-binding sites causes a derepression of the pattern throughout ventral regions, providing evidence that sna is directly responsible for establishing the mesoderm/neuroectoderm boundary before gastrulation. The tight linkage of activator and repressor sites in the rho NEE is similar to the arrangement of binding sites observed in the even-skipped stripe 2 element, which is regulated by bicoid (bcd). This suggests that the dl and bcd morphogens use a similar mechanism to make stripes in the Drosophila embryo.

Animals↗