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 analysis of the N-myc gene in bone marrow specimens at the time of initial diagnosis and as well at the time of relapse from patients with Neuroblastoma stage IV and bone marrow infiltration could give some informations about the N-myc status of these patients. In stage IV neuroblastoma patients with bone marrow infiltration an estimation of the N-myc gene amplification should be attempted, if otherwise no information about the tumor content of the N-myc gene could be gathered. In our investigation we could demonstrate a Southern-blot-analysis of 27 bone marrow specimens with respect to the N-myc gene status which correlated qualitatively well to the N-myc amplification detected later on in the corresponding tumor tissue. In six cases the tumor infiltrated bone marrow showed a clear amplification of the N-myc gene. Because of the contamination by non malignant cells in bone marrow there was a quantitative difference in the calculated N-myc gene copies between the examined bone marrow specimens and corresponding tumor tissue.
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PMID:[N-myc status of neuroblastoma from bone marrow cells]. 194 39

The prognosis of advanced neuroblastoma is extremely poor. We treated 5 patients with advanced neuroblastoma, older than 3 years, with multimodal therapy including intraoperative irradiation and autologous bone marrow transplantation. Elevated serum NSE and ferritin level and unfavorable histology according to the Shimadas histological classification, all of which are indicators of poor prognosis, were found in all of them. N-myc oncogene was amplified in 3 cases. After preoperative intensive induction chemotherapy, delayed primary operation and intraoperative irradiation (10-15 Gy) were performed. The postoperative lethal dose chemotherapy and total body irradiation (33 Gy x 3 days) were followed by autologous bone marrow transplantation. Tumor cells were purged using immunomagnetic beads method. Two cases showed recurrence (brain; 1, bone and bone marrow; 1) and a metastatic brain tumor was extirpated completely. All of them are alive during the follow up period from 6mo. to 4y8mo. (mean; 2y5mo.) with no evidence of disease except one. It may be concluded that our multimodal therapy is effective in achieving better results for advanced neuroblastoma.
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PMID:[Experience of multimodal therapy for advanced neuroblastoma]. 194 78

Eighteen patients were diagnosed and treated for Stage IV-S neuroblastoma at The Hospital for Sick Children, Toronto between January 1971 and December 1988. All patients were 6 months of age or younger at diagnosis. Nine patients (50%) have remained disease free with a mean follow-up of 9.3 years. Of the seven patients under 6 weeks of age at presentation, four presented in the early neonatal period and died, three due to mechanical complications related to progressive disease, and one due to late recurrence. The remaining three patients under 6 weeks of age, two of whom had skin involvement at diagnosis, are alive and disease free. Six of the 11 patients over 6 weeks of age at presentation survived, combined modality therapy (CMT) being more effective than single modality treatment. N-myc was studied from tumor tissue at diagnosis in four patients and was amplified in three (25x, 25x, 100x), all of whom had late disease progression and died. The patient with a single gene copy has no evidence of disease 24 months following diagnosis. Our study confirms the heterogeneity described in this clinically defined group of patients. Because of it, management of Stage IV-S neuroblastoma cannot be uniform and until further development of a subclassification, or a reclassification based on molecular biologic markers is developed, pediatric oncologists will regularly be confronted with a decision whether or not to treat a newly presenting patient that fits into the clinical classification IV-S.
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PMID:Neuroblastoma stage IV-S: a heterogeneous disease. 196 Nov 33

A series of neuroepithelioma and neuroblastoma cell lines were screened for nerve growth factor (NGF)-induced differentiation. All three neuroepithelioma cell lines and all nine neuroblastoma cell lines with amplified N-myc oncogene did not show any apparent NGF-induced differentiation. However, neurite extension was observed for three of six neuroblastoma cell lines with single-copy N-myc oncogene. The three responsive lines had a neuronal phenotype (short processes) which was enhanced by the addition of NGF. The three nonresponsive cell lines were flat without any processes. The addition of NGF to the responsive cell lines resulted in an up-regulation of neurofilament mRNA expression. Peripherin and synapsin, two markers of terminal neuronal differentiation, were not induced. There was little effect of NGF on the rate of cell growth or colony formation on soft agar. Binding of NGF to eight of the cell lines was analyzed by the method of Scatchard. Two responsive neuroblastoma cell lines and one nonresponsive neuroepithelioma cell line expressed both low- and high-affinity binding sites. Two nonresponsive neuroblastoma cell lines expressed only a small number of high-affinity binding sites, and two other nonresponsive neuroblastoma cell lines did not detectably bind NGF. Hence, NGF-induced differentiation is confined to a particular class of neural-related tumors, and, even for these cell lines, differentiation is incomplete.
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PMID:Nerve growth factor-induced differentiation of human neuroblastoma and neuroepithelioma cell lines. 196 95

Thirty-four patients of an Italian population affected by neuroblastoma (NB) were evaluated at diagnosis for multidrug resistance gene (MDR1) and N-myc oncogene amplification. No patients showed MDR1 amplification, while extra copies of the N-myc gene were found in 9 out of 34 patients (26%). N-myc amplification was correlated (p = 0.008) with a shorter progression-free survival. RNA was purified from fresh tumor biopsies and analysed in 29 NB samples. MDR1 gene expression was found to be increased in 5 out of 29 tumor samples at onset (17%) and in 1 out of 3 at relapse, but none of them expressed both MDR1 and N-myc genes simultaneously. No correlation was found between MDR1 or N-myc genes expression and tumor progression. MDR1 mRNA transcription may occur spontaneously after onset, suggesting that certain NB tumors could be resistant to antineoplastic drugs at onset. All 5 patients showing MDR1 mRNA transcription achieved complete or partial clinical remission after polychemotherapy. This was presumably due to inclusion in the therapeutic protocol of a high dose of Cisplatin, a drug not susceptible to the effects of the MDR1 gene product. Our findings show that cells which actively transcribe for the MDR1 gene are present in several untreated NB patients. No gene amplification was detected and probably the MDR1 gene expression is regulated at the transcriptional level.
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PMID:Expression of multiple drug resistance gene, MDR1, and N-myc oncogene in an Italian population of human neuroblastoma patients. 197 10

Neuroblastoma is a disease with wide spectrum clinically For the evaluation of the biological specificity of this tumor, we examined the expression of Ha-ras p21. The Ha-ras p21 detected in tumor cells showed a statistically significant association with the non-progressed tumor at the diagnosis and the favourable outcome of the patients. The association of Ha-ras p21 with their clinical outcome was closer than those of N-myc amplification. However, the complementary analyses of both Ha-ras p21 and N-myc gene seemed to provide more precise informations relating the patient's care.
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PMID:[Tumor markers--personal experience. Ha-ras P21 in neuroblastoma: a new marker associating to patient's prognosis]. 198 97

The aim of the study was to assess, in a group of nonselected patients with neuroblastoma, the prognostic value of both N-myc gene amplification and DNA ploidy index, taking into account potential confounding factors such as age and stage. Of 59 patients studied, 23 were younger than 1 year at diagnosis, 31 presented with stage IV, 10 with stage III, 5 with stage II, 8 with stage I, and 4 with stage IV-S. N-myc genomic content was analyzed by Southern blot hybridization technique and N-myc amplification (greater than or equal to 3 copies/haploid genome) was present in 6 stage IV, 2 stage III, and 1 stage IV-S. The DNA ploidy index was analyzed by flow cytometry. Of the 59 neuroblastomas, 26 were diploid (DNA index, 1) and 33 were aneuploid (DNA index, greater than 1). The majority of the aneuploid tumors (28 of 33) were near-triploid with DNA indexes between 1.25 and 1.68, 4 were near-diploid (DNA index up to 1.18), and 1 was hypotetraploid (DNA index, 1.85). The proportion of near-triploid tumors was significantly greater among patients under 1 year of age and among patients presenting with stages I, II, and IV-S. Interestingly, 0 of 28 near-triploid neuroblastomas exhibited N-myc gene amplification, compared to 9 of 31 in the group of diploid, near-diploid, and hypotetraploid tumors (Fisher's exact test, P less than 0.001). Four factors were significantly related to a high risk of relapse in univariate analysis, i.e., age, stage, DNA index, and N-myc amplification. In multivariate analysis, only N-myc amplification and the DNA index remained significantly associated with a high risk of relapse. The 2-year disease-free survival rate was 94% (95% confidence interval, 77-98%) for patients with near-triploid neuroblastoma, compared to 45 and 11% (95% confidence interval, 32-70 and 4-23%) for patients with diploid or near-diploid tumors, without and with N-myc amplification, respectively. We concluded that the combination of N-myc and DNA index should be included in routine management of neuroblastoma.
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PMID:Combined analysis of DNA ploidy index and N-myc genomic content in neuroblastoma. 198 94

Amplification of the N-myc gene in neuroblastoma correlates with advanced stage and poor prognosis. Association of the expression between N-myc and major histocompatibility complex (MHC) class I genes in 33 neuroblastomas obtained from Japanese children was investigated. Amplification of the N-myc gene was observed in two of five cases in Stage III, six of 11 cases in Stage IV, and one of five cases in Stage IV-S. In each case, the expression of N-myc gene was significantly increased. The expression was also increased in cases without amplification of the N-myc gene, the origin being from the suprarenal region. Expression of the MHC class I gene was significantly decreased in five of these nine with a high level of N-myc expression with amplification. These results suggest that the down-modulation of the MHC class I expression may be associated with the high level of expression and amplification of N-myc gene in the advanced stage of neuroblastoma.
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PMID:Association of expression between N-myc gene and major histocompatibility complex class I gene in surgically resected human neuroblastoma. 199 1

A definite association between the transcription of N-myc oncogene and proliferation-related genes, histone H3, c-myc and p53, was found in a set of 12 primary untreated neuroblastomas and a metastasis of one of these at relapse. Molecular analysis allowed us to discriminate between actually proliferating and non-proliferating tumors, and suggested a link between N-myc and proliferation. Flow cytometric analysis of DNA distribution was less reliable for assessing tumor proliferative activity. Our data also seem to indicate a down-regulation of c-myc by N-myc in human neuroblastoma.
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PMID:Transcription of N-myc and proliferation-related genes is linked in human neuroblastoma. 200 53

We detected a rearrangement in the N-myc gene region in a neuroblastoma from a 9-month-old girl. In this case, the N-myc gene was amplified 50-fold in the primary tumor, the lymph node metastasis, and the hepatic metastasis. The rearrangement was detected only in the primary tumor and the lymph node metastasis, whereas N-myc RNA and protein expression were detected only in the primary tumor and the hepatic metastasis. Both the rearranged N-myc gene and the normal N-myc gene were amplified 25-fold, and the rearrangement occurred 723 nucleotides downstream from the 3' end of exon 3. The cell line (NH-6) derived from the primary tumor showed N-myc gene amplification without this rearrangement. These results suggest the following: (a) the primary tumor had a least two clones; (b) the rearrangement interrupted N-myc gene expression; and (c) oncogenesis preceded N-myc gene amplification.
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PMID:Neuroblastoma with DNA amplification and rearrangement in the N-myc gene region. 200 81


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