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)

Impact of surgery on the result of mediastinal tumors is variable: In benign tumors such as teratoma, congenital cyst, intrathoracic struma and neurogenic tumor, a complete resection causes a good result. Simultaneous thoracotomy and laminectomy should be performed in the Dumbbell type of neurogenic tumor. Since complete resection of the invasive thymoma promises a good prognosis, excision of all the tumor and invading tissues followed by radiation therapy is recommended in the treatment of thymoma. In pure seminoma resection and radiation therapy is the treatment of choice, while in non-seminomatous germ cell tumor, aggressive chemo- and radiation therapy should be performed, until tumor markers such as AFP and HCG become negative. The operation is to be followed afterwards. A mass screening test for neuroblastoma in infant facilitates an early detection of this disease and promises a good result by chemotherapy, radiation therapy, and surgery. There is still a possibility that the result of treatment of the malignant mediastinal tumors would be improved by exact diagnosis and intensive treatment.
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PMID:[Current status of surgery for mediastinal tumors]. 930 51

Mechanisms of triiodothyronine (T3) negative regulation of the human thyrotropin-releasing hormone (TRH) gene were investigated with a chimeric construct of the 5' flanking region fused to a luciferase reporter gene, transfected into human neuroblastoma cells (HTB-11). Maximum negative regulation was achieved with constructs containing bases -242 to +54. Four sequences in this region exhibited homology with half sites of thyroid hormone response elements (TRE) (AGGTCA). The most important site was a sequence with an overlapping TRE/CRE, involving bases -53 to -60 (TGACCTCA). Potential combinatorial interactions of thyroid hormone receptors and CREB at this site were explored. Modest promoter stimulation was achieved with dibutyryl cyclic adenosine monophosphate (cAMP) (10(-3) M) plus IBMX (0.5 mM). Stimulation was greatly enhanced (+820%) by cotransfection of a constitutively activated protein kinase A (pPKA) construct. Cotransfection with pCREB increased stimulation further to 1350% above control. Stimulation of pPKA and pCREB interfered with stimulation by unliganded TRbeta1, and co-transfected pPKA and pCREB blocked T3 negative inhibition by TRbeta1-T3 complexes. When this site was mutated by polymerase chain reaction (PCR) mutagenesis, the mutant construct failed to respond to unliganded TRbeta1, and stimulation by pPKA and/or pCREB was inhibited markedly, from 12.5- to 2.1-fold, p < 0.001. Moreover, TRbeta1-T3 complexes failed to show any inhibition of the mutated promoter. These results suggest that negative regulation is achieved by inhibition of CREB stimulation of the TRH promoter at this overlapping TRE/CRE site. The two cosuppressors, NCoR and SMRT, were able to augment stimulation of the TRH promoter by unliganded TRbeta1 and enhance the magnitude of T3 inhibition. The potential role of the TRH gene and the pathophysiology of thyroid hormone resistance was investigated with three mutant TRbeta1 constructs. Thyroid hormone resistance was found to be expressed at the level of TRH gene regulation, due to lowered inhibition by mutant TRbeta1-T3 complexes and by their dominant negative effects on wild-type TRbeta1-T3 inhibition. TRH gene expression has been identified in the heart. Cardiac TRH mRNA was not regulated by T3, in contrast to HTB-11 cells, but cardiac TRH mRNA density could be augmented by glucocorticoids and by testosterone. TRH receptors were identified using Scatchard blots that showed a kilodalton of 1.4 nM and a bmax of 10 pmol/mg protein. TRH-R mRNA was identified also by reverse transcription polymerase chain reaction (RT-PCR). Enhanced ventricular contractility by TRH was demonstrated in both an open-chested dog preparation and in ex vivo ventricular myocytes, using video edge cinematography. Under controlled conditions, myocyte shortening was 13.3%, and TRH (10(-6) M) caused muscle shortening to increase 140%, (p < 0.005). TRH gene expression was demonstrated exclusively in Leydig cells of the testis. High affinity binding sites were identified in testicular membranes with a kilodalton of 1.6 x 10(-6) M. TRH was able to inhibit LH and HCG-activated testosterone secretion significantly. Thus, one paracrine role of TRH in the testis may be to serve as inhibitory modulator of gonadotropin-stimulated testosterone secretion.
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PMID:The thyrotropin-releasing hormone gene 1998: cloning, characterization, and transcriptional regulation in the central nervous system, heart, and testis. 982 56

Rapid tumour progression in neuroblastoma is associated with MYCN amplification, deletion of the short arm of chromosome 1 and gain of 17q. However, patients with advanced disease without MYCN amplification and/or 1p deletion have a very poor outcome too, which suggests other genetic defects may predict an unfavourable prognosis. We employed CGH to study 22 tumours of patients at stages 3 and 4 over one year of age (6 and 16 cases respectively). Patients were divided in groups (A) long-term survivors and (B) short-term survivors. CGH showed a total of 226 chromosome imbalances (110 in group A and 116 in group B). The neuroblastoma cells of long-term survivors showed a preponderance of numerical aberrations (54%vs 43%); particularly gains of entire chromosomes 1 (P< 0.03), 7 (P< 0.04) and 19 (P< 0.05). An extra copy of 17 was detected in 6/8 (75%) samples of group A and only 1/14 (7%) samples of group B (P< 0.002). Conversely, tumours of patients who died from disease progression displayed a higher frequency of structural abnormalities (43%vs 35%), including loss of 1p, 9p, 11q, 15q and 18q and gain of 12q, although the difference was not significant (P = 0.24). Unbalanced gain of 17q was detected in 8/14 (57%) tumours of group B and only 1/8 (13%) tumours of group A (P< 0.05). The peculiar genetic difference observed in the tumours of long and short-term survivors may have prognostic relevance.
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PMID:Numerical and structural aberrations in advanced neuroblastoma tumours by CGH analysis; survival correlates with chromosome 17 status. 1104 53

Cancer cell lines are essential gene discovery tools and have often served as models in genetic and functional studies of particular tumor types. One of the future challenges is comparison and interpretation of gene expression data with the available knowledge on the genomic abnormalities in these cell lines. In this context, accurate description of these genomic abnormalities is required. Here, we show that a combination of M-FISH with banding analysis, standard FISH, and CGH allowed a detailed description of the genetic alterations in 16 neuroblastoma cell lines. In total, 14 cryptic chromosome rearrangements were detected, including a balanced t(2;4)(p24.3;q34.3) translocation in cell line NBL-S, with the 2p24 breakpoint located at about 40 kb from MYCN. The chromosomal origin of 22 marker chromosomes and 41 cytogenetically undefined translocated segments was determined. Chromosome arm 2 short arm translocations were observed in six cell lines (38%) with and five (31%) without MYCN amplification, leading to partial chromosome arm 2p gain in all but one cell line and loss of material in the various partner chromosomes, including 1p and 11q. These 2p gains were often masked in the GGH profiles due to MYCN amplification. The commonly overrepresented region was chromosome segment 2pter-2p22, which contains the MYCN gene, and five out of eleven 2p breakpoints clustered to the interface of chromosome bands 2p16 and 2p21. In neuroblastoma cell line SJNB-12, with double minutes (dmins) but no MYCN amplification, the dmins were shown to be derived from 16q22-q23 sequences. The ATBF1 gene, an AT-binding transcription factor involved in normal neurogenesis and located at 16q22.2, was shown to be present in the amplicon. This is the first report describing the possible implication of ATBF1 in neuroblastoma cells. We conclude that a combined approach of M-FISH, cytogenetics, and CGH allowed a more complete and accurate description of the genetic alterations occurring in the investigated cell lines.
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PMID:Combined M-FISH and CGH analysis allows comprehensive description of genetic alterations in neuroblastoma cell lines. 1155 Feb 80

In neuroblastoma, the most frequent genetic alterations are unbalanced translocations involving chromosome 17. To gain insights into these rearrangements, we have characterized a previously identified der(1)t(1;17) of the CLB-Bar cell line. The 17q breakpoint was mapped by FISH. Subsequently, a rearranged fragment was identified by Southern analysis, cloned in a lambda vector and sequenced. The chromosome rearrangement is more complex than expected due to the presence of an interstitial 4p telomeric sequence between chromosome 1p and 17q. Three different genes, which may play a role in neuroblastoma development, are disrupted by the translocation breakpoints. Indeed, the 3'UTR of the PIP5K2B gene on chromosome 17q is directly fused to the (TTAGGG)n repeat of the chromosome 4p telomere, and the (1;4) fusion disrupts the MACF1 (microtubule-actin crosslinking factor 1) and POLN genes, respectively. Interestingly, the (1;4) fusion was present at diagnosis and at relapse, whereas the (4;17) fusion was detected at relapse only, leading to a secondary 17q gain confirmed by array CGH therefore indicating that 17q gain may not be a primary event in neuroblastoma. Finally, screening of a panel of neuroblastoma cell lines identified interstitial telomeric sequences in three other cases, suggesting that this may be a recurrent mechanism leading to unbalanced translocations in neuroblastoma.
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PMID:Stepwise occurrence of a complex unbalanced translocation in neuroblastoma leading to insertion of a telomere sequence and late chromosome 17q gain. 1573 7

In the past decade, microarray technology has become a major tool for high-throughput comprehensive analysis of gene expression, genotyping and re-sequencing applications. High-throughput microarrays are used for expression profiling analyses with the aims of gene or pathway discovery, tumor subclassification or relapse risk assessment. The introduction of microarray CGH provides a powerful tool to precisely detect and quantify genomic aberrations and map these directly onto the human genome. This review summarizes the current status of the application of microarray technology to neuroblastoma research.
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PMID:Application of microarray-based technology to neuroblastoma. 1595 Nov 6

Neuroblastoma (NB) is one of the most common pediatric solid tumors and displays a broad variety of genomic alterations. Array-based comparative genomic hybridization (A-CGH) is a novel technology enabling the high-resolution detection of DNA copy number aberrations. In this article, we outline features of this new technology and approaches of data analysis. We focus on stage specific DNA copy number variations in neuroblastoma detected by cDNA array-based comparative genomic hybridization (A-CGH). We also discuss hypothetic evolutionary models of neuroblastoma progression that can be derived from A-CGH data.
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PMID:High-resolution cDNA microarray-based comparative genomic hybridization analysis in neuroblastoma. 1595 Nov 7

The completion of the human genome sequence and the development of high throughput technology present exciting opportunities for the study of cancer cells. High-resolution analysis of chromosomal aberrations provides a global framework for understanding complex patterns in cancer cells, allowing us to ask hypothesis-driven questions. Genome-wide analysis of amplification and deletion of genomic regions is a critical step to resolving the mechanisms of neuroblastoma tumorigenesis. We used a high-resolution aCGH system that has over 4000 human BAC clones, resulting in an average coverage of 1Mb across the genome, to define whole genome copy number aberrations (CNAs) in a panel of human neuroblastoma-derived cell lines. By combining the aCGH data with meticulous regional validation studies, we showed that array CGH could reliably detect known aberrations including single copy gain or loss, that data correlate well with standard techniques used for the detection of these genetic changes, and that this technique can be used to identify novel regions of genomic imbalance.
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PMID:Measurement and relevance of neuroblastoma DNA copy number changes in the post-genome era. 1596 71

Understanding the genes and genetic pathways targeted by recurrent chromosomal imbalances in malignancy, along with the molecular mechanisms that generate the imbalances, are important problems in cancer biology. In this report, we demonstrate that oligonucleotide array CGH (oaCGH) analysis can routinely map chromosomal imbalance breakpoints at exon-level resolution, including imbalances that are single copy number genomic alterations. Different tiling-path array designs were used in this study: a whole-genome array with a 6-kb median probe spacing and fine-tiling arrays for selected genomic regions with either 50- or 140-bp median probe spacing. In both array formats, oligonucleotide probes were of isothermal design and were tiled through genic and inter-genic regions. Whole-genome oaCGH analysis of two neuroblastoma cell lines and three primary tumors led to the identification of 58 chromosomal breakpoints that generated 45 large-scale partial chromosomal imbalances (> 2 Mb). An unexpectedly high proportion (34%) of these breakpoint intervals mapped to regions containing segmental duplications. In addition, 88 smaller-sized regions (< 2 Mb) of imbalance were detected, the majority of which mapped to segmentally duplicated regions and may reflect constitutional copy number polymorphisms. The chromosomal breakpoints for 12 recurrent abnormalities exhibited in neuroblastoma tumors and cell lines, including MYCN amplicon boundaries, loss of 3p, loss of 11q, and gain of 17q, could be mapped to intervals ranging from 50 bp to 10 kb in size using high-density fine-tiling oligonucleotide microarrays. Fine-tiling oaCGH analysis provides an unprecedented level of resolution, allowing detailed mapping of recurrent unbalanced chromosomal abnormalities. Supplementary material for this article can be found on the Genes, Chromosomes, and Cancer website at http://www.interscience.wiley.com/jpages/1045-2257/suppmat/index.html.
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PMID:Analysis of chromosome breakpoints in neuroblastoma at sub-kilobase resolution using fine-tiling oligonucleotide array CGH. 1607 61

Three parental neuroblastoma cell lines and nine derived lines resistant to Vincristin, Doxorubicin and Cisplatin, respectively, using CGH were studied. CGH profiles of all three parental cell lines were obtained using DNA from a healthy volunteer as reference DNA. Labeled DNA from each of the drug resistant daughter cell lines and labeled DNA from their parental sensitive cell lines were hybridized to obtain a comparison of gains and losses that accompanied the development of resistance for that particular drug. All three parental cell lines were characterized by typical findings for high risk neuroblastoma: N-myc amplification, gain of 17q, and loss of 1p36.2-36.3. Acquired drug resistance in the neuroblastoma cell lines appeared to be accompanied by a large array of DNA sequence copy number changes. The regions frequently affected in chemo-resistant cell lines included gains of 13q14.1-32, and 7q11.2-31.3, 4 q. Amplifications were seen at 7q 21.1 consistent with MDR1 amplification in UKF-NB-2 VCR, UKF-NB-3 DOXO, UKF-NB-4 VCR, and UKF-NB-4 DOXO, but not in any Cisplatin resistant line. All Cisplatin and Doxorubicin and two Vincristin resistant line (UKF-NB-2 VCR and UKF-NB-4 VCR) had a deletion of part of 19q or the whole 19 chromosome. All lines resistant to Vincristin or Doxorubicin and two Cisplatin resistant lines (UKF-NB-2 CDDP and UKF-NB-4 CDDP) had a deletion of at least part of 17q, UKF-NB-4 DOXO had deletion of the whole chromosome 17. The loss of 17q may cause chemoresistance by deletion of topoisomerase IIalpha gene. Deletion of 19 q in all but one chemo-resistant lines may influence of cytochromes P450 genes which are located on 19q13.2. Also gains of 15q 22, which were detected in UKF-NB-4 VCR, UKF-NB-2 DOXO and UKF-NB-4 DO X O, may affect other cytochromes P450 genes.
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PMID:Characterization of drug-resistant neuroblastoma cell lines by comparative genomic hybridization. 1615 87


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