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)

Frequency and distribution of 5-fluorodeoxyuridine (5-FdU) plus caffeine-induced fragile sites on chromosomes of peripheral blood lymphocytes (PBL) from 10 patients with cutaneous melanoma were studied in comparison with 10 PBL samples from normal donors of corresponding sex and age. The total number of breaks showed a significant difference among individuals in both groups, however, the average frequencies of 5-FdU plus caffeine-induced, as well as spontaneous damages in PBL from melanoma patients, were higher than those from healthy volunteers. The analysis of the breakpoint distribution showed a statistically significant increase in the expression of several fragile sites. The highest enhancement was observed at 1p32 and 1p22 sites (p less than 0.001). Earlier, the increase in the expression of 1p32 fragile sites was reported for neuroblastoma patients. We believe that enhanced expression of fragile sites in 1p may play a yet-unknown pathogenetic role in the development of some neuroectodermal tumors.
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PMID:Enhanced expression of 1p32 and 1p22 fragile sites in lymphocytes in cutaneous malignant melanomas. 153 Aug 33

Cell adhesion molecules (CAMs) of the immunoglobulin supergene family may play important roles in tumorigenesis and the development of metastatic disease. In a variety of human malignancies, tumor progression has been observed to be associated with changes in CAM expression. An early event in colorectal tumorigenesis appears to be the down regulation of a normally expressed CAM, DCC. Over-expression of a second CAM, carcinoembryonic antigen, is associated with colorectal tumors which have a high risk for metastasis development. Several tumors, including Wilms tumors and neuroblastoma, have been found to express a developmentally regulated form of NCAM which inhibits a variety of cell-cell interactions. Malignant cells not only show aberrations in the expression of their CAMS and thus their normal cell-cell interactions, but establish new adhesive interactions. The development of metastatic potential in cutaneous melanoma is associated with the de novo expression of two CAMs, one of which is ICAM-1, a molecule mediating adhesion between the tumor cells and leukocytes.
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PMID:Cell adhesion molecules of the immunoglobulin supergene family and their role in malignant transformation and progression to metastatic disease. 168 May 75

The effects of L-arginine (Arg) derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells were examined. The Arg derivatives were modified at the -NH2, -COOH, C alpha-proton or guanidino group of Arg. Among the synthesized derivatives, eight compounds, i.e. the 5-(dimethylamino)-1-naphthalenesulfonyl (DNS) ones, especially N-cyclohexyl-2-(N-DNSamino)-5-guanidino-2-methylvaleramide and 1-[2-(N-DNSamino)-2-(2-imino-1,2,3,4,5,6-hexahydropyrimidin- 4-yl)acetyl]- piperidine, were found to inhibit the activity of crude guanylate cyclase in the 105,000 g supernatant fraction of the cell homogenate. The enzyme, partially purified by a column of Chelex 100 Na+, was also inhibited by these eight compounds. The mode of the inhibition was competitive. The Ki values were in the range of 2-8 microM for the enzyme in the 105,000 g supernatant fraction and 3-16 microM for the partially purified enzyme, in the presence of Mg2+ as a metal cofactor. In contrast, a new derivative, methyl 2-amino-5-guanidinovalerate (M Arg ME), as well as the Arg methyl ester (Arg ME) and Arg; were found to enhance the activity of the partially purified guanylate cyclase; KA values of M Arg ME, Arg ME and Arg were approximately 9, 4 and 3 microM respectively. From these results, the free guanidino group including 2-imino-1,2,3,4,5,6-hexahydropyrimidin-4-yl or 2-imino-1,2,3,4,5,6-hexahydropyrimidin-5-yl and modification of the --NH2 residue with a hydrophobic group such as DNS seemed to be essential for inhibition of the guanylate cyclase; however, the guanidino and --NH2 residue of Arg should be free for activation by these Arg derivatives.
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PMID:Effects of arginine derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells. 196 26

Using auto-radiographic techniques in vitro studies performed to analyse the growth rate in 13 cases of neuroblastoma, 6 recurrent tumours (assorted) and 7 metastatic tumours. The cell kinetic parameters using 3H thymidine markers, DNS synthesis, mitotic rate and mean cycle rate were investigated. The growth rate can only be calculated approximately. The results show that neuroblastomas grow incredibly fast. The cell-cycle period varies between 13.1 and 266.3 hours and averages 71 hours. Recurrent tumours have a tendency to have the same growth rate as the primary tumour. Primary metastases of Wilm's tumours and osteogenic sarcomas proliferate rapidly with a cell-cycle of 13.0- 87.0 hours (average 37.7 hours). All tumours have a distinctly individual proliferation pattern. Cell division and growth rate of malignant tumours are important in relation to radiotherapy and the use of cytotoxic drugs. These factors are expressed as a "cell-kinetic therapeutic index", which helps to predict the effectiveness of cytotoxic drugs and radiotherapy. Two cases of neuroblastoma were classified as resistant. Most tumours excluding the fibrosarcomas react well against two cytotoxic reagents. The cell-kinetic pattern and the sensitivity results are used in determining the treatment of recurrences and metastases. The relationship of these investigations in clinical practice is discussed.
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PMID:[The role of cell proliferation kinetics and cytostatica - test for sensitivity of neuroblastomas, recurrent tumours and tumour metastases (author's transl)]. 728 79

Previous studies have shown frequent mutations in the BRAF (V-raf murine sarcoma viral oncogene homolog B1) or NRAS (neuroblastoma RAS viral [V-ras] oncogene homolog) genes in cutaneous melanoma, but the relationship between these alterations and tumor cell proliferation has not been examined in human melanoma. In our study of 51 primary nodular melanomas and 18 paired metastases, we found mutations in BRAF (codon 600, previously denoted 599) in 15 primary tumors (29%) and eight metastases (44%). The figures for NRAS mutations were 27% and 22%, respectively. Mutations in BRAF and NRAS genes were mutually exclusive in all but one case, and were maintained from primary tumors through their metastases. Mutations, however, were not associated with tumor cell proliferation by Ki-67 expression, tumor thickness, microvessel density, or vascular invasion, and there were no differences in patient survival. Although BRAF and NRAS mutations are likely to be important for the initiation and maintenance of some melanomas, other factors might be more significant for proliferation and prognosis in subgroups of aggressive melanoma.
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PMID:BRAF and NRAS mutations are frequent in nodular melanoma but are not associated with tumor cell proliferation or patient survival. 1609 42

Cutaneous melanoma may be quite heterogeneous in its clinical, histologic, and molecular features. Yet, the current classification of melanoma is limited to 4 main subtypes on the basis of clinical and histopathologic features and has shown limited impact on clinical management including prognostication and treatment. Advances in our understanding of the driving molecular pathways in melanoma and the importance of the mitogen-activated protein kinase pathway have shown that specific activating mutations in oncogenes may correlate with characteristic clinical and histologic features. We evaluated 40 melanoma cases with gains in MYC at 8q24, and we show that their characteristic features include aggressive clinical course, occurrence in nonchronically sun-damaged skin, amelanotic clinical and histopathologic appearance, a nodular or primary dermal growth pattern by histology, frequent epidermal consumption, and infrequent association with a precursor nevus. The v-raf murine sarcoma viral oncogene homolog B1 (BRAF) and neuroblastoma RAS viral oncogene homolog (NRAS) mutation status was also determined. The presence of these mutations was comparable to frequencies previously reported from nonchronically sun-damaged skin. However, the BRAF mutant cases did not show histopathologic features considered characteristic of BRAF mutant melanoma. Considering these distinct clinical and histopathologic features and the possible role as a theragnostic tool, it may be of value to consider 8q24 status in cutaneous melanoma in addition to the mutation status of BRAF in future studies integrating molecular findings into the classification system for cutaneous melanoma.
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PMID:Distinctive clinical and histologic features in cutaneous melanoma with copy number gains in 8q24. 2202 39

Mutations in the three rat sarcoma (RAS) family members NRAS (neuroblastoma-RAS), HRAS (Harvey-RAS) and KRAS (Kirsten-RAS) are found in one third of human cancers. Among the first oncogenes discovered in cutaneous melanoma was NRAS, which is mutant in up to 20% of tumors causing aberrant signaling in several downstream cascades. Despite, being a highly relevant therapeutic target, design of small molecules selectively inhibiting mutant NRAS in melanoma, to date, remains an unsolved challenge. The end?
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PMID:NRAS mutant melanoma--undrugable? 2366 Jan 68

The aim of the present study was to evaluate the frequency and type of oncogenic v-raf murine sarcoma viral oncogene homolog B1 (BRAF)/neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS) mutations in cutaneous melanoma with clinically detected nodal metastases (stage IIIB and C) in relation to clinicopathological features and outcome. The clinicopathological data of 250 patients following therapeutic lymphadenectomy (LND) between 1995 and 2010, as well as BRAF/NRAS mutational status in corresponding nodal metastases, were analyzed. The median follow-up time was 53 months. BRAF mutations were detected in 154 (62%) cases (141 p.V600E, nine p.V600K and four others) and mutually exclusive NRAS mutations were detected in 42 (17%) cases. The presence of a BRAF mutation was found to correlate with patients of a younger age. The five-year overall survival (OS) rate was 33 and 43% for LND and primary tumor excision, respectively, and the five-year disease-free survival (DFS) rate for LND was 25%. No correlation was identified between BRAF/NRAS mutational status and RFS or OS (calculated from the date of the LND and primary tumor excision); for BRAF- and NRAS-mutated melanoma, the prognosis was the same for patients with wild-type (WT) melanoma. The important factors which had a negative impact on OS and DFS were as follows: Male gender, >1 metastatic lymph node and extracapsular extension of nodal metastases. The interval between the diagnosis of the initial melanoma to regional nodal metastasis (median, 10 months) was not significantly different between BRAF-mutant and -WT patients. Our largest comprehensive molecular analysis of clinical stage III melanoma revealed that BRAF and NRAS mutational status is not a prognostic marker in stage III melanoma patients with macroscopic nodal involvement, but may have implications for potential adjuvant therapy.
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PMID:Molecular alterations in clinical stage III cutaneous melanoma: Correlation with clinicopathological features and patient outcome. 2495 17

Activating mutations in neuroblastoma RAS viral oncogene homolog (NRAS) are frequent driver events in cutaneous melanoma. NRAS is a guanosine triphosphate-binding protein whose most well-characterized downstream effector is RAF, leading to activation of mitogen-activated protein kinase (MEK)-extracellular signal-regulated protein kinase 1/2 signaling. Although there are no Food and Drug Administration-approved targeted therapies for melanoma patients with a primary mutation in NRAS, one form of targeted therapy that has been explored is MEK inhibition. In clinical trials, MEK inhibitors have shown disappointing efficacy in mutant NRAS patients, the reasons for which are unclear. To explore the effects of MEK inhibitors in mutant NRAS melanoma, we used a high-throughput reverse-phase protein array platform to identify signaling alterations. Reverse-phase protein array analysis of phospho-proteomic changes in mutant NRAS melanoma in response to trametinib indicated a compensatory increase in v-akt murine thymoma viral oncogene homolog signaling and decreased expression of mitogen-inducible gene 6 (MIG6), a negative regulator of epidermal growth factor receptor/v-erb-b2 erythroblastic leukemia viral oncogene homolog receptors. MIG6 expression did not alter the growth or survival properties of mutant NRAS melanoma cells. Rather, we identified a role for MIG6 as a negative regulator of epidermal growth factor-induced signaling and cell migration and invasion. In MEK-inhibited cells, further depletion of MIG6 increased migration and invasion, whereas MIG6 expression decreased these properties. Therefore, a decrease in MIG6 may promote the migration and invasiveness of MEK-inhibited mutant NRAS melanoma, especially in response to epidermal growth factor stimulation.
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PMID:MIG6 Is MEK Regulated and Affects EGF-Induced Migration in Mutant NRAS Melanoma. 2696 78

The mitogen-activated protein kinase (MAPK) signaling pathway is a cascade of protein kinases that act in a sequential and predominantly linear fashion, albeit displaying some cross talk with other signaling cascades. Mutations in proteins integral to the MAPK signaling pathway are present in more than 50% of cutaneous melanomas. The most frequently mutated protein is v-raf murine sarcoma viral oncogene homolog B (BRAF), followed by neuroblastoma Ras viral oncogene homolog (NRAS). Recently, the development of targeted drugs for the treatment of BRAF-mutant melanoma has led to the widespread implementation of molecular assays for the detection of specific BRAF mutations. There have been some attempts to standardize testing of BRAF mutations, but this has not been achieved so far. Here we provide an updated review on the role of the MAPK signaling pathway in the pathogenesis of cutaneous melanoma, focusing on several different BRAF mutations and their diagnostic and therapeutic implications.
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PMID:Mitogen-Activated Protein Kinase Signaling Pathway in Cutaneous Melanoma: An Updated Review. 2778 45


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