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)

Little is known about the prevalence and significance of ras gene activation in neural crest tumors such as neuroblastomas, pheochromocytomas, and medullary thyroid cancers (MTCs). Therefore, we analyzed DNA from 10 human neuroblastoma cell lines and 10 primary human pheochromocytomas for activating mutations in N-ras, H-ras, and K-ras. We also studied DNA from 24 primary neuroblastomas and 10 MTCs for N-ras mutations. ras genes were analyzed by direct sequencing of specific DNA fragments amplified by the polymerase chain reaction. With the exception of the SK-N-SH cell line, the examined ras gene sequences were normal in all the neuroblastomas, pheochromocytomas, and MTCs tested. A single point mutation was identified at codon 59 (GCT(ala)----ACT(thr)) in one N-ras allele in an SK-N-SH subline. Interestingly, this mutation is different from the activating codon 61 mutation which resulted in the initial identification of N-ras from SK-N-SH DNA. Therefore, we analyzed the sequences of earlier passages and sublines of the SK-N-SH cell line, but mutations at codon 59 or 61 were not detected, suggesting that neither mutation was present in the primary tumor. Our results indicate that N-ras mutations may occur spontaneously during in vitro passage of cell lines but rarely, if ever, occur in primary neuroblastomas, pheochromocytomas, and MTCs. In addition, we have not found H-ras or K-ras mutations in any neuroblastoma cell line or primary pheochromocytoma.
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PMID:Low frequency of ras gene mutations in neuroblastomas, pheochromocytomas, and medullary thyroid cancers. 199 49

We performed expression, mutation, loss of heterozygosity (LOH) and fluorescence in situ hybridization (FISH) analyses of the p73 gene in neuroblastomas (NBs). Reverse transcription-polymerase chain reaction (RT-PCR) using primers which can detect both the p73alpha and p73beta transcripts was performed on 30 fresh NBs and 22 NB cell lines. Aberrant expression of the p73 gene was found in 4 (25%) of 16 primary tumors found by mass screening and in 10 (71.4%) of 14 primary tumors found clinically. The rates of expression in these two types of tumors were significantly different (p=0.026, Fisher's exact test). The incidence of aberrant expression of the p73 gene was significantly higher in stage IV patients than in stages I, II, III plus IVS patients (p=0.0236, Fisher's exact test). No homozygous deletions or rearrangements of the p73 gene were found in any samples examined. In addition to the polymorphism in exon 2, a silent mutation (codon 336 GCC/GCT) was found in one primary tumor. LOH of the p73 gene was detected in 5 (15%) of 33 primary NBs using PCR-LOH analysis. FISH analysis showed that all 17 NB cell lines used in this study revealed allelic loss of the p73 gene, while most of them expressed the p73 gene. These results suggest that the p73 gene is not monoallelically expressed in NB. We conclude that the p73 gene is less involved in the development but involved in the progression of neuroblastoma.
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PMID:The p73 gene is less involved in the development but involved in the progression of neuroblastoma. 1071 54

A 17-year-old man with high levels of serum AFP and hCG was diagnosed as having primary mediastinal GCT. Cisplatin-based chemotherapy decreased the biomarkers, but the mass showed further growth. Pathological examination of the resected mass revealed a mixture of immature and mature teratomas. Six months after the surgery, the patient died of a dissemination of neuroblastomatous cells, which were similar to those in the immature neural component of the primary tumor. A disseminated metastasis of neuroblastoma in immature mediastinal teratoma is a rare complication. Serum NSE can be a useful marker in detecting the metastasis.
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PMID:Disseminated metastasis of neuroblastomatous component in immature mediastinal teratoma: a case report. 1076 19

We previously reported a high incidence of loss of heterozygosity (LOH) on chromosome 2q33 in neuroblastoma (NB), observed in various types of human cancers including lung cancer, head and neck cancer and follicular thyroid carcinoma. To better elucidate the role of chromosome 2q aberrations in NB, we examined common allelic imbalance (AI) regions on chromosome 2q in 82 NB patients using 10 polymorphic microsatellite markers. AI on 2q was detected in 26 (32%) of 82 NB cases. There was a distinct common AI region between the D2S115 and D2S307 markers on 2q33. The distance between these markers was about 2.0 cM. Recently, the caspase 8 and caspase 10 genes, both of which encode cystein protease, were mapped to chromosome 2q33. Since the common AI region on 2q33 includes the caspase 8 and caspase 10 genes, the alterations of these genes were examined further. Absent or reduced expression of caspase 8 and caspase 10 were found in 19 (70%) of 27 and two (7%) of 27 NB cell lines by reverse transcription-polymerase chain reaction, respectively. A missense mutation was detected at codon 96, GCT (Alanine) to GTT (Valine), of the caspase 8 gene in one of the NB cell lines lacking caspase 8 expression. Thirteen (68%) of 19 cell lines lacking caspase 8 expression displayed methylation of the CpG island of the caspase 8 gene, whereas only one (13%) of eight cell lines with caspase 8 expression showed caspase 8 methylation (P=0.031). Furthermore, there was a significant association between AI at 2q33 and loss of caspase 8 expression (P=0.026). These results indicated that there was a tumor suppressor gene in the common AI region on chromosome 2q33 involved in the pathogenesis of a subset of NB. It is possible that the caspase 8 gene is one of the candidate tumor suppressor genes for NB and inactivation of this gene plays an important role in the tumorigenesis of NB through mainly its methylation.
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PMID:Allelic imbalance on chromosome 2q and alterations of the caspase 8 gene in neuroblastoma. 1146 26

Prediction of the best moment for the harvest of PBSCs after standard chemotherapy followed by filgrastim in children with cancer is difficult. We retrospectively analyzed the moment of harvesting of 152 procedures in 94 patients. The start of apheresis was guided by WBC count and CD34+ cell measurement in peripheral blood. We defined the first day of filgrastim administration, after completion of mobilizing chemotherapy, as day 1. Median time to harvest in different subgroups is as follows: neuroblastoma 11 days (range, 6-29 days), Ewing's sarcoma nine days (range, 7-15 days), brain tumor 10 days (range, 7-15 days), relapsed Wilms' tumor 16 days (range, 9-20 days), and extracranial GCT seven days (range, 6-14 days). Patients harvested after cyclophosphamide priming (time to harvest within a range of 8-9 days) were analyzed as a separate group. The optimal moment for harvesting in different types of tumors was highly variable, although most consistent in patients diagnosed with Ewing's sarcoma or brain tumors and after cyclophosphamide priming.
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PMID:Peripheral stem cell harvest using regular chemotherapy schedules in childhood cancer. 2288 89