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)

Human neuroblastoma (NB) cell lines treated with all-trans retinoic acid (RA) differentiate in culture, forming neurites and exhibiting growth arrest. We treated 5 human NB cell lines with RA, and observed a 2-5 fold induction of retinoic acid receptor alpha (RAR alpha) mRNA expression in 4 of the 5 cell lines, as an early cellular response. Induction of RAR alpha expression was specific for RA among several differentiating agents tested. RAR alpha mRNA expression in 13 primary neuroblastoma tumor samples was 3 fold higher in localised compared with advanced tumors (p < 0.05). RAR alpha expression may be necessary for the effects of RA on NB cells in vitro and reduced expression of this gene in vivo may contribute to the process of NB tumorigenesis.
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PMID:Regulation of retinoic acid receptor alpha expression in human neuroblastoma cell lines and tumor tissue. 801 44

Nerve growth factor (NGF), essential for differentiation and survival of sympathetic neurons is suggested to play a role in differentiation or regression of neuroblastoma. Expression of mRNA for the trk protooncogene, encoding a tyrosine kinase receptor essential for functional NGF signal transduction, and mRNA for the low affinity NGF receptor (LNGFR) was examined in 45 neuroblastomas and 3 benign ganglioneuromas using Northern blot analysis. Expression of trk mRNA and LNGFR mRNA correlated with young age, favorable clinical stages, and absence of N-myc amplification. All children (n = 19) with neuroblastomas coexpressing mRNA for trk and LNGFR are alive 8-84 months from diagnosis, regardless of age and stage. In contrast, no child (n = 15) with tumor lacking trk mRNA is alive without disease. Three subsets of patients were distinguished, one favorable (trk+, LNGFR+, n = 19, 100% survival probability), one intermediate (trk+, LNGFR-, n = 11, 62.3% survival probability), and one unfavorable (trk-, LNGFR +/-, n = 15, 0% survival probability, P < 0.001). In widespread neuroblastoma stage IVS prone to spontaneous regression, three tumors coexpressing trk and LNGFR mRNAs regressed after no or minimal therapy while the remaining tumor expressing trk but not LNGFR mRNA progressed to a fatal outcome. It is concluded that neuroblastomas coexpressing mRNA for both NGF receptor subtypes are favorable tumors likely to differentiate or regress spontaneously or respond to conventional therapy. It is further hypothesized that loss of functional NGF receptors is an important step in tumorigenesis of undifferentiated malignant childhood neuroblastoma. For these unfavorable tumors current therapy remains futile and first-line innovative therapy is justified.
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PMID:Coexpression of messenger RNA for TRK protooncogene and low affinity nerve growth factor receptor in neuroblastoma with favorable prognosis. 848 6

By screening a human fetal brain cDNA expression library using a monoclonal antiphosphotyrosine antibody and by 5' RACE procedures, we have isolated overlapping cDNAs encoding a receptor-type tyrosine kinase belonging to the EPH family, DRT (Developmentally Regulated EPH-related Tyrosine kinase gene). The DRT gene is expressed in three different size transcripts (i.e. 4, 5 and 11 kb). DRT transcripts are expressed in human brain and several other tissues, including heart, lung, kidney, placenta, pancreas, liver and skeletal muscle, but the 11 kb DRT transcript is preferentially expressed in fetal brain. Steady-state levels of DRT mRNA in several tissues, including brain, heart, lung and kidney, are greater in the midterm fetus than those in the adult. DRT transcripts are detectable at low levels in a human teratocarcinoma cell line (NTera-2), but its expression is greatly increased after the NTera-2 cells are induced to become postmitotic neurons (NTera-2N) by retinoic acid treatment. These data suggest that DRT plays a part in human neurogenesis. A large number of tumor cell lines derived from neuroectoderm express DRT transcripts, including 12 neuroblastomas, two medulloblastomas, one primitive neuroectodermal tumor and six small cell lung carcinomas (SCLC). Interestingly, several neuroblastoma cell lines with 1p deletion and one SCLC cell line express DRT transcripts of aberrant size (i.e. 3, 6 and 8 kb) in addition to those found in normal tissues. We mapped the DRT gene to human chromosome 1p35-1p36.1 by PCR screening of human-rodent somatic cell hybrid panels and by fluorescence in situ hybridization. As the distal end of chromosome 1p is often deleted in neuroblastomas and altered in some cases in SCLCs, these chromosomal abnormalities may have resulted in the generation of aberrant size transcripts. Thus, the DRT gene may play a part in neuroblastoma and SCLC tumorigenesis.
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PMID:Molecular characterization and chromosomal localization of DRT (EPHT3): a developmentally regulated human protein-tyrosine kinase gene of the EPH family. 858 79

To seek evidence that tumor regression in neuroblastoma might result from massive apoptosis, we investigated tumor cell death in 39 neuroblastomas. Characteristic histologic features of apoptosis, condensed nuclear fragments and eosinophilic cytoplasm, were observed in all specimens. A ladder of DNA fragments induced by apoptosis was demonstrated by means of DNA agarose gel electrophoresis in 18 of the 19 tumors examined. In situ DNA nick end labeling (TUNEL) stained the nuclei with DNA fragmentation in 16 of 39 neuroblastomas. The TUNEL -positive cells were distributed in a scattered fashion in 10 tumors. In the remaining six tumors, they were densely located around nonviable areas of calcifications, where karyorrhectic or pyknotic cells were frequently observed. Five of six patients with such tumors were under 12 months of age, but there was no significant difference between the two groups in the patient age, origin of the primary lesion, or tumor stage. Biological features, including histology. DNA ploidy, and N-myc amplification, were not significantly different . Double fluorescent staining for bcl-2 oncoprotein and TUNEL showed that bcl-2 oncoprotein was expressed in the cytoplasm of tumor cells that were negative for TUNEL staining. This accumulated evidence suggests that massive apoptosis of tumor cells occurs in some neuroblastomas and may be related to tumor regression, whereas inhibition of apoptosis by bcl-2 oncoprotein expression might be associated with the tumorigenesis of neuroblastomas, as reported in our previous study.
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PMID:Massive apoptosis detected by in situ DNA nick end labeling in neuroblastoma. 865 43

Recurrent genetic alterations different from the alteration of the RB1 gene on chromosome 13q14 have been described in retinoblastoma, including structural alterations on the short arm of chromosome 1 and amplification of the N-MYC oncogene. These two genetic alterations are major prognostic factors in neuroblastoma, another embryonic neuro-ectodermal tumour. In order to assess the frequency of these alterations and their possible association with clinical parameters in retinoblastoma, we studied a series of 46 retinoblastoma tumour samples. Ploidy was assessed by flow cytometry, N-MYC copy number was evaluated by a spot-blot procedure using the pNb-1 probe and loss of heterozygosity was investigated by PCR analysis at mini- and microsatellites located on the short arm of chromosome 1. Most tumours were in the diploid or near diploid range; only one case exhibited tetraploidy. N-MYC amplification was observed in only one of the 45 tumours. Loss of heterozygosity on the short arm of chromosome 1 was observed in 9/43 tumours (21%); in particular, its incidence was higher in metastatic than in localised disease (P < 0.05). We suggest that alterations of one or several genes on chromosome 1p might play a role in the oncogenesis or progression of retinoblastoma. Analysis of the long term follow-up of these and additional patients should determine the prognostic value of this parameter.
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PMID:N-MYC amplification, loss of heterozygosity on the short arm of chromosome 1 and DNA ploidy in retinoblastoma. 869 69

Overexpression of the nm23H1 gene has been associated with the suppression of metastasis in several solid tumors. However, in colorectal carcinoma and neuroblastoma, increased levels of nm23 H1 nucleoside diphosphate kinase A (NDPKA) mRNA are associated with tumorigenesis. To determine the role of nm23 H1/NDPKA in the prostate, normal and/or malignant tissue samples from 29 consecutive patients were studied. Levels of nm23 H1/NDPKA mRNA and nm23 H1/NDPKA mRNA protein were determined in tissue from 18 and 27 patients, respectively. In all, 16 of the 18 tumor samples expressed increased levels of nm23 H1/NDPKA mRNA as compared with those measured in normal tissue. The level of nm23 H1/NDPKA mRNA was > 10-fold higher in a metastatic lymph node than in normal prostate tissue. All cancer specimens and areas of prostatic intraepithelial neoplasia showed immunoreactivity with the nm23 H1/NDPKA antibody; however, normal prostatic tissue was unreactive. These findings suggest that overexpression of the nm23 H1/NDPKA gene occurs frequently in adeno-carcinomas of the prostate and may be an early event in prostate cancer tumorigenesis.
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PMID:Increased levels of nm23 H1/nucleoside diphosphate kinase A mRNA associated with adenocarcinoma of the prostate. 873 6

Familial predisposition to neuroblastoma, a common embryonal cancer of childhood, segregates as an autosomal dominant trait with high penetrance. It is therefore likely that neuroblastoma susceptibility is due to germ line mutations in a tumor suppressor gene. Cytogenetic, functional, and molecular studies have implicated chromosome band 1p36 as the most likely region to contain a suppressor gene involved in sporadic neuroblastoma tumorigenesis. We now demonstrate that neuroblastoma predisposition does not map to any of eight polymorphic markers spanning 1p36 by linkage analysis in three families. In addition, there is no loss of heterozygosity at any of these markers in tumors from affected members of these kindreds. Furthermore, there is strong evidence against linkage to two Hirschsprung disease (a condition that can cosegregate with neuroblastoma) susceptibility genes, RET and EDNRB. We conclude that the neuroblastoma susceptibility gene is distinct from the 1p36 tumor suppressor and the currently identified Hirschsprung disease susceptibility genes.
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PMID:Familial predisposition to neuroblastoma does not map to chromosome band 1p36. 875 5

Neuroblastoma occasionally occurs in diseases associated with abnormal neurocrest differentiation, e.g. Hirschsprung disease. Expression studies in developing mice suggest that the proto-oncogene RET plays a role in neurocrest differentiation. In humans expression of RET is limited to certain tumor types, including neuroblastoma, that derive from migrating neural crest cells. Mutations of RET are found associated with Hirschsprung disease. These data prompted us to investigate expression of RET and to search for gene mutations in neuroblastoma. Out of 16 neuroblastoma cell lines analyzed, 9 show clear expression of RET in a Northern blot analysis. In a single strandt conformation polymorphism (SSCP) analysis of all exons, no mutations were detected other than neutral polymorphisms. In a patient with neuroblastoma, from a family in which different neurocrestopathies, including neuroblastoma and Hirschsprung disease, had occurred, we also failed to detect RET mutations. Possibly, expression of RET in neuroblastoma merely reflects the differentiation status of the tumor cells. The absence of mutations suggests that RET does not play a crucial role in the tumorigenesis of neuroblastoma.
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PMID:No mutations found by RET mutation scanning in sporadic and hereditary neuroblastoma. 878 83

Recent advances in molecular biological techniques have increased our capability to distinguish the small differences in gene expression between subpopulations of cells found within specific tissues or tumor isolates. We use subtractive hybridization or subtractive cloning to generate information regarding genes that direct various aspects of mammalian embryonic development. The technique also is used to identify genes with specificity for particular tissues or cell types or those that regulate various processes in the cell. Also, subject to analysis is the aberrant expression of genes involved in tumorigenesis. Another use is analysis of subpopulations of cell types previously identified within individual solid tumors. We used subtractive cloning in the analysis of cell line subpopulations derived from the human pediatric tumor neuroblastoma. This has resulted in the identification of novel genes that may be useful in the study of this disease.
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PMID:cDNA subtraction hybridization: a review and an application to neuroblastoma. 885 60

The prognosis of children with neuroblastoma (NB) is dependent upon the patient's age at diagnosis, the location of the primary tumor, and histologic tumor cell differentiation. These characteristics, as well as the presumption that NB results from clonal expansion of primitive cells involved in sympathetic nervous system (SNS) development, predict that a model of tumorigenesis based upon normal fetal SNS histogenesis might indicate tumor progenitor status and define biologic and clinical behavior. Immunohistochemistry and in situ hybridization were used to examine a panel of marker gene products predicted or shown to be expressed during SNS development in the normal human fetal SNS from 8 to 24 weeks' gestational age. A similar analysis was performed in a selection of clinical NB tumors, and the results were compared. In a subset of differentiating, often extra-adrenal NB tumors in patients who frequently had a favorable outcome; advancing morphologic tumor cell differentiation spatially paralleled an advancing fetal extra-adrenal chromaffin marker gene expression phenotype (ie, increasing TrkA, TrkC, TH, IGF-2, and neuron-specific enolase expression but a lack of phenylethanolamine N-methyltransferase expression). In these tumors, expression of gene products associated with normal fetal sympathetic ganglionic differentiation (ie, Bcl-2, HNK-1, and neuropeptide Y) was lost with morphologic tumor cell differentiation. In contrast, undifferentiated tumors, the majority of which were high stage, adrenal in origin, and prognostically unfavorable, displayed marker expression characteristics mirroring that of an early fetal ganglionic lineage. Thus, we show that morphologic differentiation in stroma-poor NB tumors, long held as an important prognostic feature in tumor grading systems, often corresponds to an extra-adrenal chromaffin rather than a ganglion cell or adrenal medullary chromaffin phenotype. Understanding the biology of extra-adrenal chromaffin tissues may provide an explanation for the clinically less aggressive nature of differentiating NB tumors and suggest potential mechanisms for spontaneous regression and/or treatment response.
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PMID:A developmental model of neuroblastoma: differentiating stroma-poor tumors' progress along an extra-adrenal chromaffin lineage. 894 Dec 12


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