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 effects of transforming growth factor-beta1 (TGFbeta) on two human neuroblastoma cell lines, LAN-5 and SK-N-AS, and one human glioblastoma cell line, GL15, were evaluated. Of the three cultures, only two, SK-N-AS and GL15, had a complete response to TGFbeta, with induction of the following effects: (i) inhibition of cell proliferation; (ii) up-regulation of the extracellular matrix glycoprotein fibronectin, together with down-regulation of the VLA5 integrin receptor; (iii) up-regulation of histotype-specific cytoskeletal intermediate filaments (neurofilaments for neuroblastoma and GFAP for glioblastoma); and (iv) increase in the glycoprotein CD44, only in SK-N-AS. In the third cell line, neuroblastoma LAN-5, the effects exerted by TGFbeta consisted only of (i) neurofilament increase and (ii) morphological differentiation. The TGFbeta receptor pattern was different in each culture: SK-N-AS expressed low rates of type I and type II receptors and high rates of type III receptor; LAN-5 expressed high rates of type I, low rates of type II, and no type III; GL15 expressed high rates of all three receptors. These data suggest that TGFbeta can induce a histotype-specific cell maturation and that the neuroblastoma expressing low type II and at the same time lacking type III receptor responds only partially to TGFbeta, with induction of neural differentiation but without inhibition of cell growth.
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PMID:Transforming growth factor beta regulates differentiation and proliferation of human neuroblastoma. 894 Feb 58

Tumor specimens of 203 infants with neuroblastomas of different clinical stages-registered in successive multicenter clinical trials of the German Society of Pediatric Oncology-could be examined for N-myc amplification, chromosome 1-ploidy and-structure, CD44 std. expression (in tumor tissue, and also in patient's sera). Eighty-seven (= 43%) of these infants had a non-localized, disseminated neuroblastoma, mainly involving sympathetic nerve tissue, lymph nodes, liver, skin, bone marrow and bones (46 patients were classified into the 4 group, 41 patients in the true 4 group). If the clinical classification between stage 4 and stage 4s was neglected, then 17 of these infants (= 20%) had N-myc amplification (4-64 copies) with 16 already dead. Seven of 9 examined patients with true stage 4- had chromosome 1p aberrations (with N-myc amplification in 5), and among the dead there were 2 with CD44 negative expression. In another series, serum CD44 std. was measured by ELISA, and the highest (significantly different) Kruskal-Wallis mean rank values (147.8) were found in infants (n = 6) with stage 4s compared to the low mean-rank-value of 71.9 in patients with stage 4 (n = 65). Stage 1-3 patients (n = 42) had values of 99.8-88.6. Thus, infants with disseminated neuroblastomas, showing non-diploidy, normal chromosome 1p structure, non-N-myc amplification and high CD44 std. expression in tumor tissue, and also high CD44 std. values in serum, will have the highest chance of survival due to tumor-non-progression. On the other hand, N-myc amplification in the tumor cells was found to be characteristic for stage 4s neuroblastoma patients with tumor progression (n = 6). Therefore, 4s neuroblastoma-patients with N-myc amplified tumors should be aggressively treated like true stage 4 tumor patients.
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PMID:Disseminated neuroblastomas under 1 year of age: cell biology and prognosis. 904 47

The identification of a monoclonal antibody, AF3, which recognizes a single isoform of the cell surface protein CD44 and preferentially blocks binding of serotype 2 poliovirus to HeLa cells, suggested that CD44 might be an accessory molecule to Pvr, the cell receptor for poliovirus, and that it could play a role in the function of the poliovirus receptor site. We show here that only AF3 blocks binding of serotype 2 poliovirus to HeLa cells and, in contrast to a previously published report, that the anti-CD44 monoclonal antibodies A3D8 and IM7 are unable to block binding of poliovirus. To determine whether CD44 is involved in poliovirus infection, we analyzed the replication of all three serotypes of poliovirus in human neuroblastoma cells which lack or express CD44 and in mouse neuroblastoma cells which lack Pgp-1, the mouse homolog of human CD44, and which express Pvr. All three poliovirus serotypes replicate with normal kinetics and to normal levels in the absence or presence of CD44 or in the absence of Pgp-1. Furthermore, the binding affinity constants of all three poliovirus serotypes for Pvr are unaffected by the presence or absence of CD44 in the human neuroblastoma cell line. We conclude that CD44 and Pgp-1 are not required for poliovirus replication and are unlikely to be involved in poliovirus pathogenesis.
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PMID:CD44 is not required for poliovirus replication. 906 Jun 34

TRKA expression was evaluated on 122 untreated neuroblastomas by immunohistochemistry using an antibody with predetermined specificity. This procedure is simple and reliable for protein detection at cellular level in a routine clinical setting. Fourteen tumours were classified as benign ganglioneuroma with a restricted expression of TRKA on ganglion cells; these patients were excluded from the following analysis. A total of 108 tumours were classified as neuroblastoma or ganglioneuroblastoma; 74 expressed TRKA protein, which strongly correlated with low stage, absence of N-MYC amplification, age (<1 year), CD44 expression and favourable clinical outcome. In a univariate analysis including tumour stage, age, histology, N-MYC amplification, CD44 and TRKA expression, all parameters had significant prognostic value. The absence of TRKA expression on CD44-positive or N-MYC non-amplified tumours permits the characterization of a subgroup of patients with intermediate prognosis. However, in a multivariate analysis taking into consideration the prognostic factors mentioned above, CD44 and tumour stage were the only independent prognostic factors for the prediction of patients' event-free survival.
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PMID:Clinical relevance of TRKA expression on neuroblastoma: comparison with N-MYC amplification and CD44 expression. 909 63

With respect to a potential role for CD44 in neuronal tumors, we investigated the regulation of variant CD44 exon containing isoforms (CD44V) in the human neuroblastoma cell line SK-N-SH in response to treatment with differentiation-inducing and mitogenic factors. While the standard form of CD44 was expressed at high levels in both treated and untreated cells, variant isoforms were strongly upregulated in response to treatment with 12-O-tetradecanoyl phorbol-13-acetate (TPA), insulin-like growth factor-1 (IGF-1) and platelet-derived growth factor (PDGF) as shown by RT-PCR and immunofluorescence. One of the CD44 isoforms contains sequences encoded by variant exon v6 (CD44V6), which was originally described as a metastasis-associated antigen. Using specific inhibitors, we explored the signal transduction pathways involved in the expression of variant CD44. GF-109203X, a specific inhibitor of protein kinase C effectively blocked TPA- and IGF-1-upregulated expression of CD44v6. Wortmannin, a specific inhibitor of phosphoinositide 3-kinase (PI 3-kinase) partly reduced IGF-1 and PDGF induced CD44v6 expression. The induction of CD44V by TPA, IGF-1 or PDGF was correlated with an increased cellular binding to hyaluronic acid, a major counterreceptor for CD44. The increased binding caused by TPA or IGF-1 could specifically be blocked by the above inhibitors. Thus, PKC and PI 3-kinase are likely to transduce growth factor induced signals that upregulate specific CD44 splice variants.
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PMID:Expression of CD44 isoforms in neuroblastoma cells is regulated by PI 3-kinase and protein kinase C. 919 Aug 98

Sodium valproate (VPA) belongs to the group of simple branched-chain fatty acids and due its anticonvulsive activity is broadly applied in the treatment of epilepsy. We previously showed that VPA is able to induce cellular differentiation, to enhance immunogenicity and to inhibit proliferation of human neuroblastoma (NB) cells in vitro. Furthermore, we demonstrated that VPA inhibits proliferation, enhances neural cell adhesion molecule expression and decreases CD44 expression of human and rat glioma cells in vitro. In the present study we investigated the antitumoral effects of VPA on established human NB xenografts from UKF-NB-3 human NB cells in athymic (nude) mice. When the animals developed s.c. tumors of about 100 mm3 volume they were treated with 400 or 200 mg/kg/day VPA i.p. At the end of the treatment period (40 days) tumor volumes in animals treated with 400 and 200 mg/kg VPA were about 4- (p < 0.0001) and 2-fold (p < 0.0005) smaller than in the saline-treated control group, respectively. Histological examination of the remnant tumors of treated animals revealed induction of differentiation by induction of stroma-rich tumors and nodules that contained elongated NB cells. Pyknotic nuclei and apoptotic bodies indicated induction of apoptosis. We conclude that VPA is able to abrogate NB growth in vivo and may therefore be useful in the treatment of NB patients.
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PMID:Sodium valproate inhibits in vivo growth of human neuroblastoma cells. 943 39

Comparisons of the developing human sympathetic nervous system (SNS) to tumors presumed to derive from these cells may suggest tumor progenitors and predict tumor biologic behavior. Classic neuroblastoma (NB) and its more highly differentiated stroma-rich subtypes, extra-adrenal sympathetic paraganglioma, and pheochromocytoma were examined for the presence of the developmentally characterized gene products NSE, S-100, CD44, Bcl-2, HNK-1, PNMT, TrkA, IGF2, and tyrosine hydroxylase. The marker gene expression profiles of these tumors were compared with those similarly determined for a number of normal prenatal and postnatal human SNS cell types. Sympathetic paraganglioma, pheochromocytoma, and stroma-rich NB display marker expression profiles mimicking those of childhood sympathetic paraganglia, adrenal chromaffin cells, and sympathetic neurons, respectively. A selection of differentiating, extra-adrenal NB tumors with prognostically favorable features possess marker gene expression profiles paralleling that observed for fetal extra-adrenal sympathetic paraganglia/small intensely fluorescent cells. In contrast, undifferentiated, clinically aggressive NB tumors manifest characteristics mirroring that of embryonic/early fetal sympathetic neuroblasts of sympathetic ganglia and of the adrenal gland. These findings suggest that clinical features, such as primary tumor location and age at diagnosis, provide prognostic information for NB patients by virtue of the existence and biology of the presumed tumor progenitor cell type.
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PMID:Developmental gene expression of sympathetic nervous system tumors reflects their histogenesis. 946 Nov 20

The association of molecular characteristics with prognosis has been reported, but not their relationship with each other and their impact in the context of known clinical risk factors. In this study, data of 1249 consecutive intent-to-treat-neuroblastoma patients with more than 1 year follow-up were examined by multivariate analysis using loglinear and Cox proportional hazard regression models on a stage-related basis (stages 1-3: 600, 4S: 116, 4: 533). In a first step, risk factors were identified from 18 selected clinical variables, and risk groups defined. The second step investigated whether molecular characteristics (MYCN, LOH 1p, del 1p, CD44, N-ras, NGF-R, bcl-2, APO-1 (CD95)) contributed additional prognostic information to the model. The loglinear model demonstrated several interactions between clinical factors. By the Cox regression model, seven independent clinical risk factors were found for stages 1-3, seven for stage 4 and two for stage 4S. By subsequent introduction of all molecular variables, MYCN amplification only added significant prognostic information to the clinical factors in localised and stage 4 neuroblastoma. The models allowed the definition of risk groups for stages 1-3 patients by age (e beta = 5.09) and MYCN (e beta = 4.26), for stage 4 by MYCN (e beta = 2.78) and number of symptoms (e beta = 2.44) and for stage 4S by platelet count (e beta = 3.91) and general condition (e beta = 2.99). Molecular factors and in particular MYCN contribute significantly to risk estimation. In conjunction with clinical factors, they are powerful tools to define risk groups in neuroblastoma.
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PMID:The current contribution of molecular factors to risk estimation in neuroblastoma patients. 951 60

In contrast to MYCN amplification, expression of either trk-A or CD44 in neuroblastoma is a favourable prognostic factor and were therefore investigated in tumours from 250 patients. One hundred and eleven localised/4s (Group 1) and 139 stage 4 (Group 2) tumours were analysed. MYCN copy number was obtained by Southern blotting or PCR amplification and was detected in 28 stage 4 tumours. Trk-A and CD44 expression was detected by immunoperoxidase staining using murine monoclonal antibodies 5C3 and L178, respectively. Expression was scored as positive (homogeneous), mixed (heterogeneous) or non-reactive (negative). Trk-A expression was found in 95% of Group 1 tumours and 49% of Group 2 tumours. CD44 expression was found in 100% of Group 1 tumours, the majority of which had a strong homogeneous expression. Lack of CD44 expression occurred in 25% of tumours, all stage 4 neuroblastoma. Of the 28 MYCN amplified tumours, 27/28 (96%) were trk-A negative, and 13/28 (46%) CD44 negative. We conclude that (1) a significant percentage of stage 4 neuroblastoma express either or both trk-A and CD44, (2) the absence of CD44 expression is highly restricted to stage 4 neuroblastoma and is associated with the lack of trk-A expression, (3) trk-A negativity among CD44-positive tumours is associated with stage 4 neuroblastoma and (4) the absence of trk-A expression is highly correlated with MYCN amplification.
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PMID:Correlation of MYCN amplification, Trk-A and CD44 expression with clinical stage in 250 patients with neuroblastoma. 951 61

This multicentric analysis of tumours obtained from 140 patients with neuroblastoma confirms that the lack of CD44 expression is a highly significant factor of poor prognosis and, as previously published in multivariate analysis of the four factors, i.e. MYCN amplification, CD44 expression, age and tumour stage, CD44 expression and tumour stage were the only independent prognostic factors of event-free survival (Combaret et al., J Clin Oncol 1996, 14, 25-34). Furthermore, CD44 analysis affords significant prognostic discrimination in subgroups of patients with or without MYCN amplified tumours, both in low-stage neuroblastomas and high-grade neuroblastomas. In the subgroup of patients with low-stage neuroblastoma and the stage 4 subgroup, CD44 was the only independent prognostic factor for the prediction of event-free survival in a multivariate analysis. In conclusion, CD44 is one of the most powerful factors for predicting clinical outcome in neuroblastoma at the time of initial staging.
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PMID:Clinical relevance of CD44 cell surface expression and MYCN gene amplification in neuroblastoma. 951 62


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