Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:Malignant melanotic neuroectodermal tumor of infancy: a clinical, pathologic, ultrastructural and tissue culture study. 22 Oct 89

Human cDNA clones for NSCL-1 and NSCL-2, two basic domain helix-loop-helix (bHLH) genes expressed predominantly in the developing nervous system, were obtained from a fetal brain cDNA library. The full-length transcripts and the genomic structures were determined. The cDNAs for the two genes encode predicted proteins of similar size (133 and 135 amino acids for NSCL-1 and NSCL-2, respectively) and structure. The carboxyl-terminal 75 amino acids of the two proteins contain the bHLH motif and differ from each other by only three conservative amino acid changes, while the amino-terminal portions are markedly divergent from each other. In addition to the similar protein structure, the genes have a similar genomic organization, suggesting a close evolutionary relationship. The 5'-regulatory regions of the two genes share some features (i.e. potential TATA, CCAAT, and GATA binding sites) but also differ significantly in their G+C content. NSCL-1 is relatively G+C-rich (63%) in the sequences upstream of transcription initiation and has multiple potential binding sites for transcription factors that bind to G+C-rich sequences (e.g. AP-2). NSCL-2 is relatively A+T-rich (63%) in this region and has a potential binding site for AP1. Studies of expression in normal tissues demonstrated expression of NSCL-1 and NSCL-2 in the developing central and peripheral nervous system, most likely in developing neurons. Additional Northern analysis studies in cell lines revealed expression of these genes in some cell lines derived from tumors with neural or neuroendocrine features such as neuroblastoma, PNET, and small cell lung cancer. NSCL-1 is expressed in a larger number of these cell lines. The differences in expression may parallel differences in developmental regulation.
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PMID:A comparative structural characterization of the human NSCL-1 and NSCL-2 genes. Two basic helix-loop-helix genes expressed in the developing nervous system. 132 19

In conclusion, the group of peripheral primitive neuroectodermal tumors has been redefined in recent years on the basis of cytogenetic, molecular genetic and more precisely defined histopathologic characteristics. Although in the past, many tumors has been called Ewing's sarcoma, currently this diagnosis is limited to tumors which cannot be more specifically classified on the basis of their ultrastructural and immunophenotypic characteristics. Most small round cell tumors previously classified as Ewing's sarcoma are now classified as peripheral PNET. The consistent cytogenetic abnormality in Ewing's sarcoma and peripheral PNET and patterns of neurotransmitter enzymes have supported a common neuroectodermal origin. The precise characterization of soft tissue Ewing's sarcoma is further complicated by the several primitive rhabdomyosarcomas that may exhibit a similar light microscopic appearance. The importance of histopathologic distinction among these various round cell tumors of childhood is well recognized. Furthermore, primitive tumors with overlapping neural and mesenchymal features, known as malignant ectomesenchymoma, are now identified more often than previously. Finally, molecular biologic and cytogenetic differences between peripheral PNET and neuroblastoma have confirmed their clinical and biologic differences, in spite of their morphologic similarities. Molecular genetic and flow cytometric evaluation have contributed to the distinction of groups with prognostic significance and offer possibilities for new clinical trials.
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PMID:Peripheral primitive neuroectodermal tumors. Diagnosis, classification, and prognosis. 133 43

Transfection of a neuroblastoma cell line with expression vectors containing two different segments of human c-myb complementary DNA in antisense orientation yielded far fewer transfectant clones than did the transfection with the identical segments in sense orientation. In cell clones expressing c-myb antisense RNA, levels of the c-myb protein were down-regulated and the proliferation rate was slower than that of cells transfected with sense constructs or the untransfected parental cell line. Treatment of neuroblastoma and neuroepithelioma cell lines with a c-myb antisense oligodeoxynucleotide strongly inhibited cell growth. These data indicate a definite involvement of c-myb in the proliferation of neuroectodermal tumor cells extending the role of this protooncogene beyond the hematopoietic system. The availability of cell clones that transcribe c-myb antisense RNA provides a useful tool to study the involvement of other genes in the proliferation and differentiation of neuroblastoma cells.
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PMID:Inhibition of proliferation by c-myb antisense RNA and oligodeoxynucleotides in transformed neuroectodermal cell lines. 163 35

Most studies of antibody-dependent cellular cytotoxicity (ADCC) by polymorphonuclear leukocytes (PMN) have supported oxidative lytic processes. This may be because the studies used nonhuman or nonneoplastic cells that were highly sensitive to reactive oxygen species or were small enough to be phagocytosed by PMN. We therefore investigated whether oxygen radicals participate in PMN cytotoxicity toward human neuroectodermal solid tumor cells sensitized by 3F8, which is an anti-ganglioside GD2 murine IgG3 monoclonal antibody with documented anticancer activity in humans. A 4-h 51Cr release assay was used to assess tumor cell lysis by hydrogen peroxide, superoxide, and hypochlorite. Nine of 11 GD2(+) human melanoma and neuroblastoma cell lines had equal or greater resistance to these oxidants as compared to a GD2(-) human carcinoma line (SKBr1-III) found by others (and confirmed by us) to be significantly more resistant to oxidative lysis than a murine cell line (P388D1) representative of those commonly used in cytotoxicity assays. To facilitate detection of oxidant-mediated lysis, subsequent studies of 3F8-mediated ADCC used GD2(+) targets that were relatively sensitive and others that were relatively resistant to oxygen radicals. Normal PMN and PMN obtained from children with chronic granulomatous disease, which do not generate reactive oxygen species, were equally effective in ADCC. Granulocyte-macrophage colony-stimulating factor, which primes oxidative responses of normal but not of chronic granulomatous disease PMN, enhanced ADCC by both kinds of PMN. During ADCC of 3F8-sensitized targets, with or without granulocyte-macrophage colony-stimulating factor, GD2(-) "innocent bystander" tumor cells (including P388D1) were not lysed, a finding consistent with unimportant extracellular release of cytotoxic mediators. Finally, antioxidant and antimyeloperoxidase moieties did not block ADCC. We conclude that oxidants are not key factors in 3F8-mediated lysis by PMN of human neuroectodermal tumor cells.
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PMID:Clinically effective monoclonal antibody 3F8 mediates nonoxidative lysis of human neuroectodermal tumor cells by polymorphonuclear leukocytes. 165 2

Neuroblastoma is the most common nonhematopoietic solid tumor of childhood and has been intensively studied for at least 4 decades. Despite this, few predictive histopathologic clues to its behavior exist. Age, anatomic sites of occurrence, and clinical stage have traditionally been the only reliable prognostic factors in this disease. A number of laboratory studies that focus on biologic features such as neurotransmitter synthesis (adrenergic and noradrenergic catecholamines), neurotransmitter enzyme expression (dopamine beta hydroxylase, choline acetyl transferase), cytogenetics (homogeneously staining regions, double minute chromosomes, chromosome 1p deletions), molecular genetics (N-myc oncogene amplification and expression), and immunophenotype (surface epitopes such as HLA antigens and GD2 ganglioside and intracytoplasmic determinants such as neurofilament protein, synaptophysin, chromogranin, and neuron specific enolase) now enable the pathologist to predict clinical course in many cases and to distinguish bona fide neuroblastomas, regardless of age, site, or histologic appearance, from a host of related but distinctly separate neuroectodermal tumor entities with apparent different histogenesis, treatment sensitivity, and prognosis.
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PMID:Neuroblastoma and other childhood neural tumors: a review. 169 Apr 16

We studied two cases of pigmented neuroectodermal tumor of infancy (PNTI) by routine light microscopy and immunohistochemistry on formalin fixed, paraffin embedded tissues using antibodies to HMB-45 "melanoma associated" antigen, S-100 protein, neuron specific enolase (NSE), Leu-7 antigen, chromogranin, epithelial membrane antigen, collagen Type IV, alpha-fetoprotein and muscle-specific actin and to the intermediate filaments cytokeratin (CK), vimentin, desmin and neural filaments. We found that the large epithelioid cells, many of which contained melanin pigment, were strongly positive for CK and HMB-45, and less intensively positive for vimentin and NSE. The small neuroblast-like cells revealed only focal, weak NSE positivity. Both cell types were negative for S-100 protein and for the other antigens examined. Our results suggest that: (1) the large and small cell populations in PNTI have different immunophenotypes; (2) the expression of CK and HMB-45, together with the S-100 negativity, appears unique for the pigmented cells; and (3) this profile may be helpful in the exclusion of melanoma and peripheral neuroblastoma from the differential diagnosis.
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PMID:Pigmented neuroectodermal tumor of infancy. A light microscopic and immunohistochemical study. 170 90

The serum and cerebrospinal fluid of a patient (NB) with subacute cerebellar degeneration were found to contain a novel antineuronal autoantibody (anti-Nb). Using this antibody, we have identified and characterized antigens present in a subset of neurons in the CNS and in some neuroectodermal tumor lines. Anti-Nb antibody bound to antigens of Mr 150, 120, and 65 kDa in Western blots using extracts of human cerebellar Purkinje cells or human cerebral cortical neurons. Immunohistochemistry demonstrated relatively specific binding of anti-Nb IgG to Purkinje cells in sections of human cerebellum and to some neocortical neurons, especially those in layer VI. Because of the association of cerebellar degeneration with occult malignancies, we screened a number of tumor cell lines for immunoreactivity to anti-Nb antibody; only tumor lines of neuroectodermal origin (melanoma, small-cell lung cancer, and neuroblastoma) expressed the Nb antigen. Anti-Nb antibody thus identifies neuronal and tumor cell antigens that appear to be unique in size and distribution of expression.
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PMID:Antiserum from a patient with cerebellar degeneration identifies a novel protein in Purkinje cells, cortical neurons, and neuroectodermal tumors. 185 Dec 15

1. Neuroblastoma (NB) is an unusual neuroectodermal tumor showing a high degree of spontaneous regression. NB cells can be induced to differentiate in vitro by various agents. Cell differentiation results in morphological changes characteristic of the mature neuronal phenotype, including outgrowth of neurite-like structures with several interconnections. 2. Recent experiments indicate that morphological differentiation of NB cells is associated with changes in expression of N-myc, c-myc, and c-myb oncogenes and synthesis of neurofilament proteins. However, little is known about the transcription of neurofilament genes during differentiation. 3. We have analyzed the expression of both the N-myc oncogene and mid-size neurofilament (NF) genes in the LAN-1 human NB cell line, cultured in the presence of retinoic acid (RA). Continuous treatment with RA induced morphological differentiation within 5-6 days. The transcription of N-myc was down-modulated within 24 hr of the initial exposure to RA. The mid-size NF mRNA was increased at this time. The expression of N-myc was not modified in serum-deprived LAN-1 cells, indicating that N-myc transcription is unaffected by the arrest of the cells in the G1 phase. 4. We conclude that new synthesis of mid-size NF mRNA and a decrease in N-myc transcription precede de novo formation of neurite-like processes and morphological cell differentiation of neuroblastoma cells.
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PMID:Different regulation of mid-size neurofilament and N-myc mRNA expression during neuroblastoma cell differentiation induced by retinoic acid. 212 47

A neuroblastic-like cell line (NUB-20) was derived from a case of histopathologically diagnosed metastatic neuroblastoma. The metastatic tumor and nude mouse heterotransplant resembled neuroblastoma by histological criteria, in contrast to the primary tumor, which was differentially classified as Ewing's sarcoma. However, the cell line demonstrated a unique phenotype in culture with respect to morphology, immunohistochemical markers, and sensitivity to a battery of differentiation modulators. These characteristics, together with the presence of a chromosomal translocation (11;22),(q24;q12) and amplification with enhanced expression of the c-myc protooncogene rather than N-myc, established this tumor as neuroepithelioma. Neuroepithelioma is a tumor type distinct from, but related to, neuroblastoma in its development from the neural crest lineage. These results emphasize the growing importance of cytogenetic and molecular markers in the classification and characterization of human tumors.
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PMID:Importance of phenotypic and molecular characterization for identification of a neuroepithelioma tumor cell line, NUB-20. 215 99


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