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Sample records for oligomers neuroblastoma damaged

  1. Neuroblastoma

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Neuroblastoma KidsHealth > For Parents > Neuroblastoma Print A A A ... infancy, the chance of recovery is good. About Neuroblastoma Neuroblastoma is a rare disease in which a ...

  2. Neuroblastoma

    MedlinePlus

    Neuroblastoma is a very rare type of cancerous tumor that develops from nerve tissue. It usually occurs ... Neuroblastoma can occur in many areas of the body. It develops from the tissues that form the ...

  3. Rare Individual Amyloid-β Oligomers Act on Astrocytes to Initiate Neuronal Damage

    PubMed Central

    2014-01-01

    Oligomers of the amyloid-β (Aβ) peptide have been implicated in the neurotoxicity associated with Alzheimer’s disease. We have used single-molecule techniques to examine quantitatively the cellular effects of adding well characterized Aβ oligomers to primary hippocampal cells and hence determine the initial pathway of damage. We found that even picomolar concentrations of Aβ (1–40) and Aβ (1–42) oligomers can, within minutes of addition, increase the levels of intracellular calcium in astrocytes but not in neurons, and this effect is saturated at a concentration of about 10 nM of oligomers. Both Aβ (1–40) and Aβ (1–42) oligomers have comparable effects. The rise in intracellular calcium is followed by an increase in the rate of ROS production by NADPH oxidase in both neurons and astrocytes. The increase in ROS production then triggers caspase-3 activation resulting in the inhibition of long-term potentiation. Our quantitative approach also reveals that only a small fraction of the oligomers are damaging and that an individual rare oligomer binding to an astrocyte can initiate the aforementioned cascade of responses, making it unlikely to be due to any specific interaction. Preincubating the Aβ oligomers with an extracellular chaperone, clusterin, sequesters the oligomers in long-lived complexes and inhibits all of the physiological damage, even at a ratio of 100:1, total Aβ to clusterin. To explain how Aβ oligomers are so damaging but that it takes decades to develop Alzheimer’s disease, we suggest a model for disease progression where small amounts of neuronal damage from individual unsequestered oligomers can accumulate over time leading to widespread tissue-level dysfunction. PMID:24717093

  4. Neuroblastoma

    PubMed Central

    Hoover, Eddie L.; Hsu, Hwei-Kang; Dressler, Carolyn; Fani, Kazim; Webb, Hueldine; Ketosugbo, Anukware; Kharma, Bassam

    1988-01-01

    Mediastinal neuroblastomas, which are common malignancies of childhood, are extremely rare in adults. This article presents a case of mediastinal neuroblastoma in a 57-year-old man. To the authors' knowledge, this is only the second recorded case of such a tumor in an adult. The patient's clinical course is described and is compared with other cases (in children, except for one instance) cited in the literature. The authors discuss the early diagnosis and surgical management of these uncommon lesions, which tend to be quite extensive and rapidly fatal, and which should be suspected in adults who present with a mediastinal mass. (Texas Heart Institute Journal 1988;15:107-112) Images PMID:15227261

  5. MYCN sensitizes human neuroblastoma to apoptosis by HIPK2 activation through a DNA damage response.

    PubMed

    Petroni, Marialaura; Veschi, Veronica; Prodosmo, Andrea; Rinaldo, Cinzia; Massimi, Isabella; Carbonari, Maurizio; Dominici, Carlo; McDowell, Heather P; Rinaldi, Christian; Screpanti, Isabella; Frati, Luigi; Bartolazzi, Armando; Gulino, Alberto; Soddu, Silvia; Giannini, Giuseppe

    2011-01-01

    MYCN amplification occurs in approximately 20% of human neuroblastomas and is associated with early tumor progression and poor outcome, despite intensive multimodal treatment. However, MYCN overexpression also sensitizes neuroblastoma cells to apoptosis. Thus, uncovering the molecular mechanisms linking MYCN to apoptosis might contribute to designing more efficient therapies for MYCN-amplified tumors. Here we show that MYCN-dependent sensitization to apoptosis requires activation of p53 and its phosphorylation at serine 46. The p53(S46) kinase HIPK2 accumulates on MYCN expression, and its depletion by RNA interference impairs p53(S46) phosphorylation and apoptosis. Remarkably, MYCN induces a DNA damage response that accounts for the inhibition of HIPK2 degradation through an ATM- and NBS1-dependent pathway. Prompted by the rare occurrence of p53 mutations and by the broad expression of HIPK2 in our human neuroblastoma series, we evaluated the effects of the p53-reactivating compound Nutlin-3 on this pathway. At variance from other tumor histotypes, in MYCN-amplified neuroblastoma, Nutlin-3 further induced HIPK2 accumulation, p53(S46) phosphorylation, and apoptosis, and in combination with clastogenic agents purged virtually the entire cell population. Altogether, our data uncover a novel mechanism linking MYCN to apoptosis that can be triggered by the p53-reactivating compound Nutlin-3, supporting its use in the most difficult-to-treat subset of neuroblastoma. PMID:21173028

  6. SGO1 is involved in the DNA damage response in MYCN-amplified neuroblastoma cells

    PubMed Central

    Murakami-Tonami, Yuko; Ikeda, Haruna; Yamagishi, Ryota; Inayoshi, Mao; Inagaki, Shiho; Kishida, Satoshi; Komata, Yosuke; Jan Koster, J K; Takeuchi, Ichiro; Kondo, Yutaka; Maeda, Tohru; Sekido, Yoshitaka; Murakami, Hiroshi; Kadomatsu, Kenji

    2016-01-01

    Shugoshin 1 (SGO1) is required for accurate chromosome segregation during mitosis and meiosis; however, its other functions, especially at interphase, are not clearly understood. Here, we found that downregulation of SGO1 caused a synergistic phenotype in cells overexpressing MYCN. Downregulation of SGO1 impaired proliferation and induced DNA damage followed by a senescence-like phenotype only in MYCN-overexpressing neuroblastoma cells. In these cells, SGO1 knockdown induced DNA damage, even during interphase, and this effect was independent of cohesin. Furthermore, MYCN-promoted SGO1 transcription and SGO1 expression tended to be higher in MYCN- or MYC-overexpressing cancers. Together, these findings indicate that SGO1 plays a role in the DNA damage response in interphase. Therefore, we propose that SGO1 represents a potential molecular target for treatment of MYCN-amplified neuroblastoma. PMID:27539729

  7. SGO1 is involved in the DNA damage response in MYCN-amplified neuroblastoma cells.

    PubMed

    Murakami-Tonami, Yuko; Ikeda, Haruna; Yamagishi, Ryota; Inayoshi, Mao; Inagaki, Shiho; Kishida, Satoshi; Komata, Yosuke; Jan Koster; Takeuchi, Ichiro; Kondo, Yutaka; Maeda, Tohru; Sekido, Yoshitaka; Murakami, Hiroshi; Kadomatsu, Kenji

    2016-01-01

    Shugoshin 1 (SGO1) is required for accurate chromosome segregation during mitosis and meiosis; however, its other functions, especially at interphase, are not clearly understood. Here, we found that downregulation of SGO1 caused a synergistic phenotype in cells overexpressing MYCN. Downregulation of SGO1 impaired proliferation and induced DNA damage followed by a senescence-like phenotype only in MYCN-overexpressing neuroblastoma cells. In these cells, SGO1 knockdown induced DNA damage, even during interphase, and this effect was independent of cohesin. Furthermore, MYCN-promoted SGO1 transcription and SGO1 expression tended to be higher in MYCN- or MYC-overexpressing cancers. Together, these findings indicate that SGO1 plays a role in the DNA damage response in interphase. Therefore, we propose that SGO1 represents a potential molecular target for treatment of MYCN-amplified neuroblastoma. PMID:27539729

  8. Checkpoint kinase inhibitor synergizes with DNA-damaging agents in G1 checkpoint-defective neuroblastoma.

    PubMed

    Xu, Hong; Cheung, Irene Y; Wei, Xiao X; Tran, Hoa; Gao, Xiaoni; Cheung, Nai-Kong V

    2011-10-15

    Checkpoint kinase inhibitors can enhance the cancer killing action of DNA-damaging chemotherapeutic agents by disrupting the S/G(2) cell cycle checkpoints. The in vitro and in vivo effects of the Chk1/2 inhibitor AZD7762 when combined with these agents were examined using neuroblastoma cell lines with known p53/MDM2/p14(ARF) genomic status. Four of four p53 mutant lines and three of five MDM2/p14(ARF) abnormal lines were defective in G(1) checkpoint, correlating with failure to induce endogenous p21 after treatment with DNA-damaging agents. In cytotoxicity assays, these G(1) checkpoint-defective lines were more resistant to DNA-damaging agents when compared to G(1) checkpoint intact lines, yet becoming more sensitive when AZD7762 was added. Moreover, AZD7762 abrogated DNA damage-induced S/G(2) checkpoint arrest both in vitro and in vivo. In xenograft models, a significant delay in tumor growth accompanied by histological evidence of increased apoptosis was observed, when AZD7762 was added to the DNA-damaging drug gemcitabine. These results suggest a therapeutic potential of combination therapy using checkpoint kinase inhibitor and chemotherapy to reverse or prevent drug resistance in treating neuroblastomas with defective G(1) checkpoints. PMID:21154747

  9. DNA damage promotes Herpes Simplex Virus-1 protein expression in a neuroblastoma cell line

    PubMed Central

    Volcy, Ketna; Fraser, Nigel W.

    2013-01-01

    Although the induction of the cellular DNA damage response by Herpes simplex virus-1 (HSV-1) infection of epithelial cells in tissue culture promotes productive infection, there has been no experimental observation of the effect of the cellular DNA damage response on HSV-1 infection in vivo or in neuronal derived cell lines in tissue culture. Thus, it has been speculated that the lack of cellular DNA damage induction during infection of neurons may promote latency in these cells. This work examines the profile of HSV-1 promoter induction and protein expression, in the absence or presence of infection; using cellular DNA damage inducing topoisomerase inhibitors (Camptothecin and Etoposide) on a neuroblastoma cell line (C1300) in which HSV-1 infection fails to induce the DNA damage response. In the absence of infection, a plasmid expressing the immediate early ICP0 promoter was the most induced by the DNA damage drug treatments compared to the early (RR) and late (VP16) gene promoters. Similarly, drug treatment of C1300 cells infected with HSV-1 virus showed enhanced protein expression for ICP0, but not ICP4 and VP16 proteins. However, when the cells were infected with a HSV-1 virus defective in the immediate early gene trans-activator VP16 (in814) and treated with the DNA damaging drugs, there was enhanced expression of immediate early and late HSV-1 proteins. Although, viral infection of the neuroblastoma cell alone did not induce DNA damage, cellular DNA damage induced by drug treatments facilitated viral promoter induction and viral protein expression. This implicates a mechanism by which HSV-1 viral genes in a quiescent or latent state may become induced by cellular DNA damage in neuronal cells to facilitate productive infection. PMID:23354549

  10. Antiapoptotic effects of roscovitine on camptothecin-induced DNA damage in neuroblastoma cells.

    PubMed

    Pizarro, Javier G; Folch, Jaume; Junyent, Felix; Verdaguer, Ester; Auladell, Carme; Beas-Zarate, Carlos; Pallàs, Mercè; Camins, Antoni

    2011-05-01

    In the present study dopaminergic neuroblastoma B65 cells were exposed to Camptothecin (CPT) (0.5-10 μM), either alone or in the presence of roscovitine (ROSC). The results show that CPT induces apoptosis through the activation of ataxia telangiectasia mutated (ATM)-induced cell-cycle alteration in neuroblastoma B65 cells. The apoptotic process is mediated through the activation of cystein proteases, namely calpain/caspases. However, whereas a pan-caspase inhibitor, zVADfmk, inhibited CPT-mediated apoptosis, a calpain inhibitor, calpeptin, did not prevent cell death. Interestingly, CPT also induces CDK5 activation and ROSC (25 μM) blocked CDK5, ATM activation and apoptosis (as measured by caspase-3 activation). By contrast, selective inhibition of ATM, by KU55933, and non-selective inhibition, by caffeine, did not prevent CPT-mediated apoptosis. Thus, we conclude that CDK5 is activated in response to DNA damage and that CDK5 inhibition prevents ATM and p53ser15 activation. However, pharmacological inhibition of ATM using KU55933 and caffeine suggests that ATM inhibition by ROSC is not the only mechanism that might explain the anti-apoptotic effects of this drug in this apoptosis model. Our findings have a potential clinical implication, suggesting that combinatory drugs in the treatment of cancer activation should be administered with caution. PMID:21424556

  11. How Is Neuroblastoma Diagnosed?

    MedlinePlus

    ... and can provide a picture of the entire skeleton at once. Neuroblastoma often causes bone damage, which ... settles in areas of damaged bone throughout the skeleton over the course of a couple of hours. ...

  12. Mitochondrial Damage and Apoptosis Induced by Adenosine Deaminase Inhibition and Deoxyadenosine in Human Neuroblastoma Cell Lines.

    PubMed

    Garcia-Gil, Mercedes; Tozzi, Maria Grazia; Balestri, Francesco; Colombaioni, Laura; Camici, Marcella

    2016-07-01

    The treatment with deoxycoformycin, a strong adenosine deaminase inhibitor, in combination with deoxyadenosine, causes apoptotic cell death of two human neuroblastoma cell lines, SH-SY5Y and LAN5. Herein we demonstrate that, in SH-SY5Y cells, this combination rapidly decreases mitochondrial reactive oxygen species and, in parallel, increases mitochondrial mass, while, later, induces nuclear fragmentation, and activation of caspase-8, -9, and -3. In previous papers we have shown that a human astrocytoma cell line, subjected to the same treatment, undergoes apoptotic death as well. Therefore, both astrocytoma and neuroblastoma cell lines undergo apoptotic death following the combined treatment with deoxycoformycin and deoxyadenosine, but several differences have been found in the mode of action, possibly reflecting a different functional and metabolic profile of the two cell lines. Overall this work indicates that the neuroblastoma cell lines, like the line of astrocytic origin, are very sensitive to purine metabolism perturbation thus suggesting new therapeutic approaches to nervous system tumors. J. Cell. Biochem. 117: 1671-1679, 2016. © 2015 Wiley Periodicals, Inc. PMID:26659614

  13. Repression of BIRC5/Survivin by FOXO3/FKHRL1 Sensitizes Human Neuroblastoma Cells to DNA Damage-induced Apoptosis

    PubMed Central

    Hagenbuchner, Judith; Unterkircher, Thomas; Sachsenmaier, Nora; Seifarth, Christoph; Böck, Günther; Porto, Verena; Geiger, Kathrin; Ausserlechner, Michael

    2009-01-01

    The phosphatidylinositol 3-kinase (PI3K)–protein kinase B (PKB) pathway regulates survival and chemotherapy resistance of neuronal cells, and its deregulation in neuroblastoma (NB) tumors predicts an adverse clinical outcome. Here, we show that inhibition of PI3K-PKB signaling in human NB cells induces nuclear translocation of FOXO3/FKHRL1, represses the prosurvival protein BIRC5/Survivin, and sensitizes to DNA-damaging agents. To specifically address whether FKHRL1 contributes to Survivin regulation, we introduced a 4-hydroxy-tamoxifen-regulated FKHRL1(A3)ERtm allele into NB cells. Conditional FKHRL1 activation repressed Survivin transcription and protein expression. Transgenic Survivin exerted a significant antiapoptotic effect and prevented the accumulation of Bim and Bax at mitochondria, the loss of mitochondrial membrane potential as well as the release of cytochrome c during FKHRL1-induced apoptosis. In concordance, Survivin knockdown by retroviral short hairpin RNA technology accelerated FKHRL1-induced apoptosis. Low-dose activation of FKHRL1 sensitized to the DNA-damaging agents doxorubicin and etoposide, whereas the overexpression of Survivin diminished FKHRL1 sensitization to these drugs. These results suggest that repression of Survivin by FKHRL1 facilitates FKHRL1-induced apoptosis and sensitizes to cell death induced by DNA-damaging agents, which supports the central role of PI3K-PKB-FKHRL1 signaling in drug resistance of human NB. PMID:19211844

  14. Aqueous dispersions of oligomer-grafted carbon nanomaterials with controlled surface charge and minimal framework damage

    PubMed Central

    Hu, Sheng; Chen, Shu; Menzel, Robert; Goode, Angela D.; Ryan, Mary P.; Porter, Alexandra E.; Shaffer, Milo S. P.

    2015-01-01

    Functionalised carbon nanomaterials (CNMs), with an undamaged carbon framework and controlled physiochemical properties, are desirable for a wide range of scientific studies and commercial applications. The use of a thermochemical grafting approach provides a versatile means to functionalise both multi-walled carbon nanotubes (MWCNTs) and carbon black (CB) nanoparticles without altering their inherent structure. The functionalisation process was investigated by employing various types of grafting monomers; to improve water solubility, reagents were chosen that introduced ionic character either intrinsically or after further chemical reaction. The degree of grafting for both MWCNTs and CB ranged from 3 to 27 wt%, as established by thermal gravimetric analysis (TGA). Raman spectroscopy confirmed that the structural framework of the MWNTs was unaffected by the thermochemical treatment. The effectiveness of the surface modification was demonstrated by significantly improved dispersibility and stability in water, and further quantified by zeta-potential analysis. The concentration of stable, individualised, grafted MWNTs in water ranged from 30 to 80 µg mL−1, whereas functionalised CB (CB) in water showed improved dispersibility up to ~460 µg mL−1 after centrifugation at 10, 000 g for 15 minutes. The successful preparation of structurally identical but differently functionalised nanoparticles panels, with high water compatibility and minimal framework damage, are useful for controlled experiments. For example, they can be used to explore the relationship between toxicological effects and specific physiochemical properties, such as surface charge and geometry. PMID:25254653

  15. What Is Neuroblastoma?

    MedlinePlus

    ... are the key statistics about neuroblastoma? What is neuroblastoma? Cancer starts when cells in the body begin ... see the section, “ Signs and symptoms of neuroblastoma ”). Neuroblastomas Neuroblastomas are cancers that start in early nerve ...

  16. The synergistic effects of DNA-damaging drugs cisplatin and etoposide with a histone deacetylase inhibitor valproate in high-risk neuroblastoma cells.

    PubMed

    Groh, Tomas; Hrabeta, Jan; Khalil, Mohammed Ashraf; Doktorova, Helena; Eckschlager, Tomas; Stiborova, Marie

    2015-07-01

    High-risk neuroblastoma remains one of the most important therapeutic challenges for pediatric oncologists. New agents or regimens are urgently needed to improve the treatment outcome of this fatal tumor. We examined the effect of histone deacetylase (HDAC) inhibitors in a combination with other chemotherapeutics on a high-risk neuroblastoma UKF-NB-4 cell line. Treatment of UKF-NB-4 cells with DNA-damaging chemotherapeutics cisplatin or etoposide combined with the HDAC inhibitor valproate (VPA) resulted in the synergistic antitumor effect. This was associated with caspase-3-dependent induction of apoptosis. Another HDAC inhibitor trichostatin A and a derivative of VPA that does not exhibit HDAC inhibitory activity, valpromide, lacked this effect. The synergism was only induced when VPA was combined with cytostatics targeted to cellular DNA; VPA does not potentiate the cytotoxicity of the anticancer drug vincristine that acts by a mechanism different from that of DNA damage. The VPA-mediated sensitization of UKF-NB-4 cells to cisplatin or etoposide was dependent on the sequence of drug administration; the potentiating effect was only produced either by simultaneous treatment with these drugs or when the cells were pretreated with cisplatin or etoposide before their exposure to VPA. The synergistic effects of VPA with cisplatin or etoposide were associated with changes in the acetylation status of histones H3 and H4. The results of this study provide a rationale for clinical evaluation of the combination of VPA and cisplatin or etoposide for treating children suffering from high-risk neuroblastoma. PMID:25963435

  17. Amyloid-β oligomers induce synaptic damage via Tau-dependent microtubule severing by TTLL6 and spastin

    PubMed Central

    Zempel, Hans; Luedtke, Julia; Kumar, Yatender; Biernat, Jacek; Dawson, Hana; Mandelkow, Eckhard; Mandelkow, Eva-Maria

    2013-01-01

    Mislocalization and aggregation of Aβ and Tau combined with loss of synapses and microtubules (MTs) are hallmarks of Alzheimer disease. We exposed mature primary neurons to Aβ oligomers and analysed changes in the Tau/MT system. MT breakdown occurs in dendrites invaded by Tau (Tau missorting) and is mediated by spastin, an MT-severing enzyme. Spastin is recruited by MT polyglutamylation, induced by Tau missorting triggered translocalization of TTLL6 (Tubulin-Tyrosine-Ligase-Like-6) into dendrites. Consequences are spine loss and mitochondria and neurofilament mislocalization. Missorted Tau is not axonally derived, as shown by axonal retention of photoconvertible Dendra2-Tau, but newly synthesized. Recovery from Aβ insult occurs after Aβ oligomers lose their toxicity and requires the kinase MARK (Microtubule-Affinity-Regulating-Kinase). In neurons derived from Tau-knockout mice, MTs and synapses are resistant to Aβ toxicity because TTLL6 mislocalization and MT polyglutamylation are prevented; hence no spastin recruitment and no MT breakdown occur, enabling faster recovery. Reintroduction of Tau re-establishes Aβ-induced toxicity in TauKO neurons, which requires phosphorylation of Tau's KXGS motifs. Transgenic mice overexpressing Tau show TTLL6 translocalization into dendrites and decreased MT stability. The results provide a rationale for MT stabilization as a therapeutic approach. PMID:24065130

  18. Genetics Home Reference: neuroblastoma

    MedlinePlus

    ... Help Me Understand Genetics Home Health Conditions neuroblastoma neuroblastoma Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Neuroblastoma is a type of cancer that most often ...

  19. Congenital neuroblastoma

    PubMed Central

    Evans, A. R.

    1965-01-01

    The clinical histories and post-mortem findings in five cases of neuroblastoma are described, and an account given of the microscopic characteristics of the tumours. In four of the cases the tumour was present at birth and was probably so in the fifth case. In only one case was the presence of the malignant tumour a significant factor in causing death. The differential diagnosis of such tumours is discussed. The accumulated evidence of many recorded cases suggests that neuroblastoma, becoming manifest in the early months or weeks of life, and congenital tumour, would be included in such a group, and has an appreciably better prognosis than has this same tumour when it becomes manifest in later childhood. The literature is briefly reviewed to illustrate this aspect of prognosis and possible reasons for it are indicated. Images PMID:14247705

  20. Effects of Antidepressants on DSP4/CPT-Induced DNA Damage Response in Neuroblastoma SH-SY5Y Cells.

    PubMed

    Wang, Yan; Hilton, Benjamin A; Cui, Kui; Zhu, Meng-Yang

    2015-08-01

    DNA damage is a form of cell stress and injury. Increased systemic DNA damage is related to the pathogenic development of neurodegenerative diseases. Depression occurs in a relatively high percentage of patients suffering from degenerative diseases, for whom antidepressants are often used to relieve depressive symptoms. However, few studies have attempted to elucidate why different groups of antidepressants have similar effects on relieving symptoms of depression. Previously, we demonstrated that neurotoxins N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4)- and camptothecin (CPT) induced the DNA damage response in SH-SY5Y cells, and DSP4 caused cell cycle arrest which was predominately in the S-phase. The present study shows that CPT treatment also resulted in similar cell cycle arrest. Some classic antidepressants could reduce the DNA damage response induced by DSP4 or CPT in SH-SY5Y cells. Cell viability examination demonstrated that both DSP4 and CPT caused cell death, which was prevented by spontaneous administration of some tested antidepressants. Flow cytometric analysis demonstrated that a majority of the tested antidepressants protect cells from being arrested in S-phase. These results suggest that blocking the DNA damage response may be an important pharmacologic characteristic of antidepressants. Exploring the underlying mechanisms may allow for advances in the effort to improve therapeutic strategies for depression appearing in degenerative and psychiatric diseases. PMID:26038195

  1. Olfactory neuroblastoma

    SciTech Connect

    O'Connor, T.A.; McLean, P.; Juillard, G.J.; Parker, R.G.

    1989-06-15

    Fifteen patients with olfactory neuroblastoma were treated during the 17-year period of 1969 to 1986. Data was analyzed with respect to age at presentation, sex, presenting signs and symptoms, stage, and results of treatment. Age ranged from 4 to 67 years with the median age being 27 years. Median follow-up was 8 years. Local control was achieved in nine of nine patients or 100% with successful surgical resection, i.e., minimal residual disease, followed by postoperative radiation therapy (45 to 65 Gy) was employed. There were no distant failures when the primary site was controlled. Regional lymph node metastases were infrequent: only 13% (two of 15 patients) presented with positive nodes. Three of four patients treated initially with surgery alone had a local recurrence, two of which were successfully salvaged by combined therapy. There were four patients treated with radiation therapy alone: three had persistent disease after radiation therapy, and one patient was controlled with 65 Gy. Olfactory neuroblastoma has a propensity to recur locally when treated with surgery alone. The authors' experience suggests excellent local control can be achieved with surgery immediately followed by radiation therapy. Thus the authors recommend planned combined treatment for all resectable lesions.

  2. Protease Omi cleaving Hax-1 protein contributes to OGD/R-induced mitochondrial damage in neuroblastoma N2a cells and cerebral injury in MCAO mice

    PubMed Central

    Wu, Jia-yuan; Li, Mei; Cao, Li-juan; Sun, Mei-ling; Chen, Dong; Ren, Hai-gang; Xia, Qin; Tao, Zhou-teng; Qin, Zheng-hong; Hu, Qing-song; Wang, Guang-hui

    2015-01-01

    Aim: In the penumbra after focal cerebral ischemia, an increase of protease Omi is linked to a decrease of Hs1-associated protein X-1 (Hax-1), a protein belonging to the Bcl-2 family. In this study we investigated the mechanisms underlying the regulation of Hax-1 by protease Omi in cerebral ischemia/reperfusion (I/R) injury. Methods: Mouse neuroblastoma N2a cells were subjected to oxygen-glucose deprivation and reoxygenation (OGD/R); cell viability was assessed with MTT assay. Mice underwent 2-h middle cerebral artery occlusion (MCAO) and reperfusion, and the infarct volume was determined with TTC staining. The expression of Omi and Hax-1 was detected using immunoblot and immunofluorescence assays. The mitochondrial membrane potential was measured using TMRM staining. Results: In the brains of MCAO mice, the protein level of Omi was significantly increased, while the protein level of Hax-1 was decreased. Similar changes were observed in OGD/R-treated N2a cells, but the mRNA level of Hax-1 was not changed. Furthermore, in OGD/R-treated N2a cells, knockdown of Omi significantly increased Hax-1 protein level. Immunofluorescence assay showed that Omi and Hax-1 were co-localized in mitochondria of N2a cells. OGD/R caused marked mitochondrial damage and apoptosis in N2a cells, while inhibition of Omi protease activity with UCF-101 (10 μmol/L) or overexpression of Hax-1 could restore the mitochondrial membrane potential and attenuate cell apoptosis. Moreover, pretreatment of MCAO mice with UCF-101 (7.15 mg/kg, ip) could restore Hax-1 expression, inhibit caspase activation, and significantly reduce the infarct volume. Conclusion: Protease Omi impairs mitochondrial function by cleaving Hax-1, which induces apoptosis in OGD/R-treated N2a cells and causes I/R injury in MCAO mice. PMID:26299953

  3. Cell Proliferation in Neuroblastoma.

    PubMed

    Stafman, Laura L; Beierle, Elizabeth A

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  4. Cell Proliferation in Neuroblastoma

    PubMed Central

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  5. EGb761 provides a protective effect against Aβ1-42 oligomer-induced cell damage and blood-brain barrier disruption in an in vitro bEnd.3 endothelial model.

    PubMed

    Wan, Wen-bin; Cao, Lan; Liu, Lu-mei; Kalionis, Bill; Chen, Chuan; Tai, Xian-tao; Li, Ya-ming; Xia, Shi-jin

    2014-01-01

    Alzheimer's disease (AD) is the most common form of senile dementia which is characterized by abnormal amyloid beta (Aβ) accumulation and deposition in brain parenchyma and cerebral capillaries, and leads to blood-brain barrier (BBB) disruption. Despite great progress in understanding the etiology of AD, the underlying pathogenic mechanism of BBB damage is still unclear, and no effective treatment has been devised. The standard Ginkgo biloba extract EGb761 has been widely used as a potential cognitive enhancer for the treatment of AD. However, the cellular mechanism underlying the effect remain to be clarified. In this study, we employed an immortalized endothelial cell line (bEnd.3) and incubation of Aβ(1-42) oligomer, to mimic a monolayer BBB model under conditions found in the AD brain. We investigated the effect of EGb761 on BBB and found that Aβ1-42 oligomer-induced cell injury, apoptosis, and generation of intracellular reactive oxygen species (ROS), were attenuated by treatment with EGb761. Moreover, treatment of the cells with EGb761 decreased BBB permeability and increased tight junction scaffold protein levels including ZO-1, Claudin-5 and Occludin. We also found that the Aβ(1-42) oligomer-induced upregulation of the receptor for advanced glycation end-products (RAGE), which mediates Aβ cytotoxicity and plays an essential role in AD progression, was significantly decreased by treatment with EGb761. To our knowledge, we provide the first direct in vitro evidence of an effect of EGb761 on the brain endothelium exposed to Aβ(1-42) oligomer, and on the expression of tight junction (TJ) scaffold proteins and RAGE. Our results provide a new insight into a possible mechanism of action of EGb761. This study provides a rational basis for the therapeutic application of EGb761 in the treatment of AD. PMID:25426944

  6. Phenylethynyl terminated imide oligomers

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Bryant, Robert G. (Inventor); Jensen, Brian J. (Inventor); Havens, Stephen J. (Inventor)

    1995-01-01

    Four phenylethynyl amine compounds - 3 and 4-aminophenoxy-4'-phenylethynylbenzophenone, and 3 and 4-amino-4'-phenylethynylbenzophenone - were readily prepared and were used to endcap imide oligomers. Phenylethynyl-terminated amide acid oligomers and phenylethynyl-terminated imide oligomers with various molecular weights and compositions were prepared and characterized. These oligomers were cured at 300 to 400 C to provide crosslinked polyimides with excellent solvent resistance, high strength and modulus, and good high temperature properties. Adhesive panels, composites, films, and moldings from these phenylethynyl terminated imide oligomers gave excellent mechanical performance.

  7. Ferulic Acid Regulates the Nrf2/Heme Oxygenase-1 System and Counteracts Trimethyltin-Induced Neuronal Damage in the Human Neuroblastoma Cell Line SH-SY5Y

    PubMed Central

    Catino, Stefania; Paciello, Fabiola; Miceli, Fiorella; Rolesi, Rolando; Troiani, Diana; Calabrese, Vittorio; Santangelo, Rosaria; Mancuso, Cesare

    2016-01-01

    Over the past years, several lines of evidence have pointed out the efficacy of ferulic acid (FA) in counteracting oxidative stress elicited by β-amyloid or free radical initiators, based on the ability of this natural antioxidant to up-regulate the heme oxygenase-1 (HO-1) and biliverdin reductase (BVR) system. However, scarce results can be found in literature regarding the cytoprotective effects of FA in case of damage caused by neurotoxicants. The aim of this work is to investigate the mechanisms through which FA exerts neuroprotection in SH-SY5Y neuroblastoma cells exposed to the neurotoxin trimethyltin (TMT). FA (1–10 μM for 6 h) dose-dependently increased both basal and TMT (10 μM for 24 h)-induced HO-1 expression in SH-SY5Y cells by fostering the nuclear translocation of the transcriptional activator Nrf2. In particular, the co-treatment of FA (10 μM) with TMT was also responsible for the nuclear translocation of HO-1 in an attempt to further increase cell stress response in SH-SY5Y cells. In addition to HO-1, FA (1–10 μM for 6 h) dose-dependently increased the basal expression of BVR. The antioxidant and neuroprotective features of FA, through the increase of HO activity, were supported by the evidence that FA inhibited TMT (10 μM)-induced lipid peroxidation (evaluated by detecting 4-hydroxy-nonenal) and DNA fragmentation in SH-SY5Y cells and that this antioxidant effect was reversed by the HO inhibitor Zinc-protoporphyrin-IX (5 μM). Among the by-products of the HO/BVR system, carbon monoxide (CORM-2, 50 nM) and bilirubin (BR, 50 nM) significantly inhibited TMT-induced superoxide anion formation in SH-SY5Y cells. All together, these results corroborate the neuroprotective effect of FA through the up-regulation of the HO-1/BVR system, via carbon monoxide and BR formation, and provide the first evidence on the role of HO-1/Nrf2 axis in FA-related enhancement of cell stress response in human neurons. PMID:26779023

  8. Neuroblastoma: A neurochemical approach

    SciTech Connect

    Schor, N.F. )

    1991-07-01

    Neuroblastoma is among the most common malignancies of childhood. Despite greatly improved therapy for some pediatric tumors, the prognosis for children with metastatic neuroblastoma has not changed significantly in the past 10 years. With conventional chemotherapy, radiation therapy, and surgery, children with metastatic neuroblastoma have a 20% long-term survival rate. The authors describe here approaches to neuroblastoma that target its neuronal characteristics. On the one hand, the neurotransmitter receptors on the surface of the neuroblastoma cells and, on the other hand, specific isozymes that distinguish neuroblastoma cells from their normal counterparts are the focus of these experimental therapies. In the former case, specificity for tumor cells is effected by (1) selective protection of normal neuronal elements from toxicity, or (2) selective potentiation of toxicity for neural tumor cells. It is hoped that these strategies will be generalizable to other neural crest-derived tumors. 32 references.

  9. [NEUROBLASTOMA IN PEDIATRIC PATIENTS].

    PubMed

    Solovyov, A E; Morgun, V V; Paholchuk, A P

    2015-06-01

    Neuroblastoma the most common malignant tumor of childhood, which is often localized in the retroperitoneal space, mainly in the adrenal glands, paravertebral retroperitoneal space, at rare in the posterior mediastinum, in the neck, presacral area. First symptoms of neuroblastoma are nonspecific, mimic various diseases. In the following clinical manifestations depend on the localization of the tumor, stage presence and location of metastases. In the diagnosis of neuroblastoma using ultrasonography and computed tomography. Of the 26 children whose neuroblastoma detected in different periods have died 12. Radical removal of the tumor only effective the first year of life. Chemotherapy is effective in 50% of operated children. PMID:26521471

  10. Advances in neuroblastoma research

    SciTech Connect

    Evans, A.E.; D'Angio, G.J.; Seeger, R.C.

    1985-01-01

    This book contains over 50 papers. Some of the titles are: Studies on the expression of the amplified domain in human neuroblastoma cells; Comparison studies of oncogenes in retinoblastoma and neuroblastoma; Chromosome abnormalities, gene amplification and tumor progression; and Peripheral neuroepithelioma: Genetic analysis of tumor derived cell lines.

  11. Real-time investigation of cytochrome c release profiles in living neuronal cells undergoing amyloid beta oligomer-induced apoptosis

    NASA Astrophysics Data System (ADS)

    Lee, Jae Young; Park, Younggeun; Pun, San; Lee, Sung Sik; Lo, Joe F.; Lee, Luke P.

    2015-06-01

    Intracellular Cyt c release profiles in living human neuroblastoma undergoing amyloid β oligomer (AβO)-induced apoptosis, as a model Alzheimer's disease-associated pathogenic molecule, were analysed in a real-time manner using plasmon resonance energy transfer (PRET)-based spectroscopy.Intracellular Cyt c release profiles in living human neuroblastoma undergoing amyloid β oligomer (AβO)-induced apoptosis, as a model Alzheimer's disease-associated pathogenic molecule, were analysed in a real-time manner using plasmon resonance energy transfer (PRET)-based spectroscopy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02390d

  12. ABC transporters and neuroblastoma.

    PubMed

    Yu, Denise M T; Huynh, Tony; Truong, Alan M; Haber, Michelle; Norris, Murray D

    2015-01-01

    Neuroblastoma is the most common cancer of infancy and accounts for 15% of all pediatric oncology deaths. Survival rates of high-risk neuroblastoma remain less than 50%, with amplification of the MYCN oncogene the most important aberration associated with poor outcome. Direct transcriptional targets of MYCN include a number of ATP-binding cassette (ABC) transporters, of which ABCC1 (MRP1), ABCC3 (MRP3), and ABCC4 (MRP4) are the best characterized. These three transporter genes have been shown to be strongly prognostic of neuroblastoma outcome in primary untreated neuroblastoma. In addition to their ability to efflux a number of chemotherapeutic drugs, evidence suggests that these transporters also contribute to neuroblastoma outcome independent of any role in cytotoxic drug efflux. Endogenous substrates of ABCC1 and ABCC4 that may be potential candidates affecting neuroblastoma biology include molecules such as prostaglandins and leukotrienes. These bioactive lipid mediators have the ability to influence biological processes contributing to cancer initiation and progression, such as angiogenesis, cell signaling, inflammation, proliferation, and migration and invasion. ABCC1 and ABCC4 are thus potential targets for therapeutic suppression in high-risk neuroblastoma, and recently developed small-molecule inhibitors may be an effective strategy in treating aggressive forms of this cancer, as well as other cancers that express high levels of these transporters. PMID:25640269

  13. Neuroblastoma and MYCN

    PubMed Central

    Huang, Miller; Weiss, William A.

    2013-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, is thought to originate from undifferentiated neural crest cells. Amplification of the MYC family member, MYCN, is found in ∼25% of cases and correlates with high-risk disease and poor prognosis. Currently, amplification of MYCN remains the best-characterized genetic marker of risk in neuroblastoma. This article reviews roles for MYCN in neuroblastoma and highlights recent identification of other driver mutations. Strategies to target MYCN at the level of protein stability and transcription are also reviewed. PMID:24086065

  14. Immune Therapies for Neuroblastoma

    PubMed Central

    Navid, Fariba; Armstrong, Michael; Barfield, Raymond C.

    2009-01-01

    Neuroblastoma, a solid tumor arising from developing cells of the sympathetic nervous system, is the most common extracranial tumor in children. The prognosis for high-risk neuroblastoma remains poor with conventional treatment, and new approaches are therefore being explored to treat this disease. One such alternative therapy that holds promise is immune therapy. We review here the recent advances in 4 types of immune therapy – cytokine, vaccine, antibody, and cellular therapy – to treat neuroblastoma. We present preclinical research and clinical trials on several promising candidates such as IL-12, dendritic cell vaccines, anti-GD2 antibodies, and allogeneic hematopoietic stem cell transplant. An optimal treatment plan for neuroblastoma will most likely involve multimodal approaches and combinations of immune therapies. PMID:19342881

  15. Drugs Approved for Neuroblastoma

    Cancer.gov

    This page lists cancer drugs approved by the Food and Drug Administration (FDA) for neuroblastoma. The list includes generic names and brand names. The drug names link to NCI's Cancer Drug Information summaries.

  16. Melatonin prevents cytosolic calcium overload, mitochondrial damage and cell death due to toxically high doses of dexamethasone-induced oxidative stress in human neuroblastoma SH-SY5Y cells.

    PubMed

    Suwanjang, Wilasinee; Abramov, Andrey Y; Charngkaew, Komgrid; Govitrapong, Piyarat; Chetsawang, Banthit

    2016-07-01

    Stressor exposure activates the hypothalamic-pituitary-adrenal (HPA) axis and causes elevations in the levels of glucocorticoids (GC) from the adrenal glands. Increasing evidence has demonstrated that prolonged exposure to high GC levels can lead to oxidative stress, calcium deregulation, mitochondrial dysfunction and apoptosis in a number of cell types. However, melatonin, via its antioxidant activity, exhibits a neuroprotective effect against oxidative stress-induced cell death. Therefore, in the present study, we explored the protective effect of melatonin in GC-induced toxicity in human neuroblastoma SH-SY5Y cells. Cellular treatment with the toxically high doses of the synthetic GC receptor agonist, dexamethasone (DEX) elicited marked decreases in the levels of glutathione and increases in ROS production, lipid peroxidation and cell death. DEX toxicity also induced increases in the levels of cytosolic calcium and mitochondrial fusion proteins (Mfn1 and Opa1) but decreases in the levels of mitochondrial fission proteins (Fis1 and Drp1). Mitochondrial damage was observed in large proportions of the DEX-treated cells. Pretreatment of the cells with melatonin substantially prevented the DEX-induced toxicity. These results suggest that melatonin might exert protective effects against oxidative stress, cytosolic calcium overload and mitochondrial damage in DEX-induced neurotoxicity. PMID:27155536

  17. Imaging in neuroblastoma: An update

    PubMed Central

    Kembhavi, Seema A; Shah, Sneha; Rangarajan, Venkatesh; Qureshi, Sajid; Popat, Palak; Kurkure, Purna

    2015-01-01

    Neuroblastoma is the third common tumor in children. Imaging plays an important role in the diagnosis, staging, treatment planning, response evaluation and in follow-up of a case of Neuroblastoma. The International Neuroblastoma Risk Group task force has recently introduced an imaging-based staging system and laid down guidelines for uniform reporting of imaging studies. This review is an update on imaging in neuroblastoma, with emphasis on these guidelines. PMID:25969636

  18. Amyloid β peptide oligomers directly activate NMDA receptors.

    PubMed

    Texidó, Laura; Martín-Satué, Mireia; Alberdi, Elena; Solsona, Carles; Matute, Carlos

    2011-03-01

    Amyloid beta (Aβ) oligomers accumulate in the brain tissue of Alzheimer disease patients and are related to disease pathogenesis. The precise mechanisms by which Aβ oligomers cause neurotoxicity remain unknown. We recently reported that Aβ oligomers cause intracellular Ca(2+) overload and neuronal death that can be prevented by NMDA receptor antagonists. This study investigated whether Aβ oligomers directly activated NMDA receptors (NMDARs) using NR1/NR2A and NR1/NR2B receptors that were heterologously expressed in Xenopus laevis oocytes. Indeed, Aβ oligomers induced inward non-desensitizing currents that were blocked in the presence of the NMDA receptor antagonists memantine, APV, and MK-801. Intriguingly, the amplitude of the responses to Aβ oligomers was greater for NR1/NR2A heteromers than for NR1/NR2B heteromers expressed in oocytes. Consistent with these findings, we observed that the increase in the cytosolic concentration of Ca(2+) induced by Aβ oligomers in cortical neurons is prevented by AP5, a broad spectrum NMDA receptor antagonist, but slightly attenuated by ifenprodil which blocks receptors with the NR2B subunit. Together, these results indicate that Aβ oligomers directly activate NMDA receptors, particularly those with the NR2A subunit, and further suggest that drugs that attenuate the activity of such receptors may prevent Aβ damage to neurons in Alzheimeŕs disease. PMID:21349580

  19. Phenylethynyl terminated reactive oligomer

    NASA Technical Reports Server (NTRS)

    Bryant, Robert G. (Inventor); Jensen, Brian J. (Inventor); Hergenrother, Paul M. (Inventor)

    1995-01-01

    A composition of matter having the general structure: ##STR1## (wherein X is F, Cl, or NO.sub.2, and Y is CO, SO.sub.2 or C(CF.sub.3).sub.2) is employed to terminate a nucleophilic reagent, resulting in the exclusive production of phenylethynyl terminated reactive oligomers which display unique thermal characteristics. A reactive diluent having the general structure: ##STR2## (wherein R is any aliphatic or aromatic moiety) is employed to decrease the melt viscosity of a phenylethynyl terminated reactive oligomer and to subsequently react therewith to provide a thermosetting material of enhanced density. These materials have features which make them attractive candidates for use as composite matrices and adhesives.

  20. What Are the Key Statistics about Neuroblastoma?

    MedlinePlus

    ... risk factors for neuroblastoma? What are the key statistics about neuroblastoma? Neuroblastoma is by far the most ... parts of the body when it is diagnosed. Statistics related to survival are discussed in the section “ ...

  1. Structure of amyloid oligomers and their mechanisms of toxicities: Targeting amyloid oligomers using novel therapeutic approaches.

    PubMed

    Salahuddin, Parveen; Fatima, Munazza Tamkeen; Abdelhameed, Ali Saber; Nusrat, Saima; Khan, Rizwan Hasan

    2016-05-23

    Protein misfolding is one of the leading causes of amyloidoses. Protein misfolding occurs from changes in environmental conditions and host of other factors, including errors in post-translational modifications, increase in the rate of degradation, error in trafficking, loss of binding partners and oxidative damage. Misfolding gives rise to the formation of partially unfolded or misfolded intermediates, which have exposed hydrophobic residues and interact with complementary intermediates to form oligomers and consequently protofibrils and fibrils. The amyloid fibrils accumulate as amyloid deposits in the brain and central nervous system in Alzheimer's disease (AD), Prion disease and Parkinson's disease (PD). Initial studies have shown that amyloid fibrils were the main culprit behind toxicity that cause neurodegenerative diseases. However, attention shifted to the cytotoxicity of amyloid fibril precursors, notably amyloid oligomers, which are the major cause of toxicity. The mechanism of toxicity triggered by amyloid oligomers remains elusive. In this review, we have focused on the current knowledge of the structures of different aggregated states, including amyloid fibril, protofibrils, annular aggregates and oligomers. Based on the studies on the mechanism of toxicities, we hypothesize two major possible mechanisms of toxicities instigated by oligomers of Aβ (amyloid beta), PrP (prion protein) (106-126), and α-Syn (alpha-synuclein) including direct formation of ion channels and neuron membrane disruption by the increase in membrane conductance or leakage in the presence of small globulomers to large prefibrillar assemblies. Finally, we have discussed various novel innovative approaches that target amyloid oligomers in Alzheimer's diseases, Prion disease and Parkinson's disease. PMID:26974374

  2. Salsolinol Damaged Neuroblastoma SH-SY5Y Cells Induce Proliferation of Human Monocyte THP-1 Cells Through the mTOR Pathway in a Co-culture System.

    PubMed

    Wang, Fuli; Ni, Junjun; Wang, Xianghan; Xie, Bingjie; Feng, Chengcheng; Zhao, Sibo; Saeed, Yasmeem; Qing, Hong; Deng, Yulin

    2015-05-01

    Despite extensive efforts to study the inflammatory process in the central nervous system of Parkinson's disease (PD) patients, little is known about the role of peripheral blood mononuclear cells (PBMCs) in PD. In the present study, we used an in vitro co-culture system to study the role of the human monocyte cell line THP-1 in medium conditioned by the neuroblastoma cell line SH-SY5Y damaged with the endogenous neurotoxin 1-methyl-4-phenyl-1,2,3,4-tetrahydroisoquinoline (Salsolinol, Sal) in co-culture with the human glioma cell line U87. For this purpose, SH-SY5Y and U87 co-cultures were treated with Sal, and this conditioned medium containing mediators, including the potential effector CCL2, was isolated and applied to THP-1 cells. This treatment resulted in approximately 19 % cell proliferation as well as activation of mTOR and induction of phosphorylated 4E-BP1, S6K1, PI3K, and AKT proteins. Treatment with rapamycin, an mTOR inhibitor, attenuated the proliferation of THP-1 cells. U87 glial cells were essential for this as medium conditioned without them had no effect on THP-1 cells. These results suggest a positive effect of THP-1 cells on Sal-induced neurotoxicity in a cellular model of PD and this is likely mediated by the enhancement of cell proliferation through activation of the mTOR signaling pathway. Hence, PBMCs and their mTOR signaling pathway could be of therapeutic benefit in treating the endogenous neurotoxin-induced neuroinflammation in PD. PMID:25773262

  3. Alzheimer's amyloid-β oligomers rescue cellular prion protein induced tau reduction via the Fyn pathway.

    PubMed

    Chen, Rong-Jie; Chang, Wei-Wei; Lin, Yu-Chun; Cheng, Pei-Lin; Chen, Yun-Ru

    2013-09-18

    Amyloid-β (Aβ) and tau are the pathogenic hallmarks in Alzheimer's disease (AD). Aβ oligomers are considered the actual toxic entities, and the toxicity relies on the presence of tau. Recently, Aβ oligomers have been shown to specifically interact with cellular prion protein (PrP(C)) where the role of PrP(C) in AD is still not fully understood. To investigate the downstream mechanism of PrP(C) and Aβ oligomer interaction and their possible relationships to tau, we examined tau expression in human neuroblastoma BE(2)-C cells transfected with murine PrP(C) and studied the effect under Aβ oligomer treatment. By Western blotting, we found that PrP(C) overexpression down-regulated tau protein and Aβ oligomer binding alleviated the tau reduction induced by wild type but not M128V PrP(C), the high AD risk polymorphic allele in human prion gene. PrP(C) lacking the Aβ oligomer binding site was incapable of rescuing the level of tau reduction. Quantitative RT-PCR showed the PrP(C) effect was attributed to tau reduction at the transcription level. Treatment with Fyn pathway inhibitors, Fyn kinase inhibitor PP2 and MEK inhibitor U0126, reversed the PrP(C)-induced tau reduction and Aβ oligomer treatment modulated Fyn kinase activity. The results suggested Fyn pathway regulated Aβ-PrP(C)-tau signaling. Overall, our results demonstrated that PrP(C) down-regulated tau via the Fyn pathway and the effect can be regulated by Aβ oligomers. Our study facilitated the understanding of molecular mechanisms among PrP(C), tau, and Aβ oligomers. PMID:23805846

  4. Monoclonal antibodies and neuroblastoma

    SciTech Connect

    Miraldi, F. )

    1989-10-01

    Several antineuroblastoma monoclonal antibodies (MoAbs) have been described and two have been used in radioimmunoimaging and radioimmunotherapy in patients. MoAb 3F8 is a murine IgG3 antibody specific for the ganglioside GD2. Radioiodine-labeled 3F8 has been shown to specifically target human neuroblastoma in patients, and radioimmunoimaging with this agent has provided consistently high uptakes with tumor-to-background ratios of greater than or equal to 10:1. Radioimmunotherapy has been attempted with both MoAb 3F8 and MoAb UJ13A, and although encouraging results have been obtained, dosimetry data and tissue dose response information for these agents is lacking, which impedes the development of such therapy. 124I, a positron emitter, can be used with 3F8 in positron emission tomography (PET) scanning to provide dosimetry information for radioimmunotherapy. The tumor radiation dose response from radiolabeled MoAb also can be followed with PET images with fluorodeoxyglucose (FDG) scanning of neuroblastoma tumors. Results to date indicate that radioimmunoimaging has clinical use in the diagnosis of neuroblastoma and the potential for radioimmunotherapy for this cancer remains high.48 references.

  5. Mechanisms of neuroblastoma regression

    PubMed Central

    Brodeur, Garrett M.; Bagatell, Rochelle

    2014-01-01

    Recent genomic and biological studies of neuroblastoma have shed light on the dramatic heterogeneity in the clinical behaviour of this disease, which spans from spontaneous regression or differentiation in some patients, to relentless disease progression in others, despite intensive multimodality therapy. This evidence also suggests several possible mechanisms to explain the phenomena of spontaneous regression in neuroblastomas, including neurotrophin deprivation, humoral or cellular immunity, loss of telomerase activity and alterations in epigenetic regulation. A better understanding of the mechanisms of spontaneous regression might help to identify optimal therapeutic approaches for patients with these tumours. Currently, the most druggable mechanism is the delayed activation of developmentally programmed cell death regulated by the tropomyosin receptor kinase A pathway. Indeed, targeted therapy aimed at inhibiting neurotrophin receptors might be used in lieu of conventional chemotherapy or radiation in infants with biologically favourable tumours that require treatment. Alternative approaches consist of breaking immune tolerance to tumour antigens or activating neurotrophin receptor pathways to induce neuronal differentiation. These approaches are likely to be most effective against biologically favourable tumours, but they might also provide insights into treatment of biologically unfavourable tumours. We describe the different mechanisms of spontaneous neuroblastoma regression and the consequent therapeutic approaches. PMID:25331179

  6. Promising therapeutic targets in neuroblastoma

    PubMed Central

    Matthay, Katherine K.; George, Rani E.; Yu, Alice L.

    2012-01-01

    Neuroblastoma, the most common extra- cranial solid tumor in children, is derived from neural crest cells. Nearly half of patients present with metastatic disease, and have 5-year EFS of less than 50%. New approaches with targeted therapy may improve efficacy without increased toxicity. The current review will evaluate three promising targeted therapies, including 131I-metaiodobenzylguanidine (MIBG), a radiopharmaceutical taken up by the human norepinephrine transporter expressed in 90% of neuroblastomas, immunotherapy with monoclonal antibodies targeting the GD2 ganglioside, expressed on 98% of neuroblastoma cells, and inhibitors of ALK, a tyrosine kinase which is mutated or amplified in approximately 10% of neuroblastoma and expressed on the surface of most neuroblastoma cells. Early phase trials have confirmed the activity of 131I-MIBG in relapsed neuroblastoma, with response rates of about 30%, but the technical aspects of administration of large amounts of radioactivity in young children and the limited access have hindered incorporation into treatment of newly diagnosed patients. Anti-GD2 antibodies have also demonstrated activity in relapsed disease, and a recent phase III randomized trial showed a significant improvement in event-free survival for patients receiving chimeric anti-GD2 (ch14.18) combined with cytokines and isotretinoin after myeloablative consolidation therapy. A recently approved small molecule inhibitor of ALK has promising pre-clinical activity for neuroblastoma, and is currently in phase I and II trials. This is the first agent directed to a specific mutation in neuroblastoma, and marks a new step toward personalized therapy for neuroblastoma. Further clinical development of targeted treatments offers new hope for children with neuroblastoma. PMID:22589483

  7. Promising therapeutic targets in neuroblastoma.

    PubMed

    Matthay, Katherine K; George, Rani E; Yu, Alice L

    2012-05-15

    Neuroblastoma, the most common extracranial solid tumor in children, is derived from neural crest cells. Nearly half of patients present with metastatic disease and have a 5-year event-free survival of <50%. New approaches with targeted therapy may improve efficacy without increased toxicity. In this review we evaluate 3 promising targeted therapies: (i) (131)I-metaiodobenzylguanidine (MIBG), a radiopharmaceutical that is taken up by human norepinephrine transporter (hNET), which is expressed in 90% of neuroblastomas; (ii) immunotherapy with monoclonal antibodies targeting the GD2 ganglioside, which is expressed on 98% of neuroblastoma cells; and (iii) inhibitors of anaplastic lymphoma kinase (ALK), a tyrosine kinase that is mutated or amplified in ~10% of neuroblastomas and expressed on the surface of most neuroblastoma cells. Early-phase trials have confirmed the activity of (131)I-MIBG in relapsed neuroblastoma, with response rates of ~30%, but the technical aspects of administering large amounts of radioactivity in young children and limited access to this agent have hindered its incorporation into treatment of newly diagnosed patients. Anti-GD2 antibodies have also shown activity in relapsed disease, and a recent phase III randomized trial showed a significant improvement in event-free survival for patients receiving chimeric anti-GD2 (ch14.18) combined with cytokines and isotretinoin after myeloablative consolidation therapy. A recently approved small-molecule inhibitor of ALK has shown promising preclinical activity for neuroblastoma and is currently in phase I and II trials. This is the first agent directed to a specific mutation in neuroblastoma, and marks a new step toward personalized therapy for neuroblastoma. Further clinical development of targeted treatments offers new hope for children with neuroblastoma. PMID:22589483

  8. Transthyretin suppresses the toxicity of oligomers formed by misfolded proteins in vitro.

    PubMed

    Cascella, Roberta; Conti, Simona; Mannini, Benedetta; Li, Xinyi; Buxbaum, Joel N; Tiribilli, Bruno; Chiti, Fabrizio; Cecchi, Cristina

    2013-12-01

    Although human transthyretin (TTR) is associated with systemic amyloidoses, an anti-amyloidogenic effect that prevents Aβ fibril formation in vitro and in animal models has been observed. Here we studied the ability of three different types of TTR, namely human tetramers (hTTR), mouse tetramers (muTTR) and an engineered monomer of the human protein (M-TTR), to suppress the toxicity of oligomers formed by two different amyloidogenic peptides/proteins (HypF-N and Aβ42). muTTR is the most stable homotetramer, hTTR can dissociate into partially unfolded monomers, whereas M-TTR maintains a monomeric state. Preformed toxic HypF-N and Aβ42 oligomers were incubated in the presence of each TTR then added to cell culture media. hTTR, and to a greater extent M-TTR, were found to protect human neuroblastoma cells and rat primary neurons against oligomer-induced toxicity, whereas muTTR had no protective effect. The thioflavin T assay and site-directed labeling experiments using pyrene ruled out disaggregation and structural reorganization within the discrete oligomers following incubation with TTRs, while confocal microscopy, SDS-PAGE, and intrinsic fluorescence measurements indicated tight binding between oligomers and hTTR, particularly M-TTR. Moreover, atomic force microscopy (AFM), light scattering and turbidimetry analyses indicated that larger assemblies of oligomers are formed in the presence of M-TTR and, to a lesser extent, with hTTR. Overall, the data suggest a generic capacity of TTR to efficiently neutralize the toxicity of oligomers formed by misfolded proteins and reveal that such neutralization occurs through a mechanism of TTR-mediated assembly of protein oligomers into larger species, with an efficiency that correlates inversely with TTR tetramer stability. PMID:24075940

  9. Ataxia-telangiectasia mutated (ATM) silencing promotes neuroblastoma progression through a MYCN independent mechanism

    PubMed Central

    Mandriota, Stefano J.; Valentijn, Linda J.; Lesne, Laurence; Betts, David R.; Marino, Denis; Boudal-Khoshbeen, Mary; London, Wendy B.; Rougemont, Anne-Laure; Attiyeh, Edward F.; Maris, John M.; Hogarty, Michael D.; Koster, Jan; Molenaar, Jan J.; Versteeg, Rogier

    2015-01-01

    Neuroblastoma, a childhood cancer with highly heterogeneous biology and clinical behavior, is characterized by genomic aberrations including amplification of MYCN. Hemizygous deletion of chromosome 11q is a well-established, independent marker of poor prognosis. While 11q22-q23 is the most frequently deleted region, the neuroblastoma tumor suppressor in this region remains to be identified. Chromosome bands 11q22-q23 contain ATM, a cell cycle checkpoint kinase and tumor suppressor playing a pivotal role in the DNA damage response. Here, we report that haploinsufficiency of ATM in neuroblastoma correlates with lower ATM expression, event-free survival, and overall survival. ATM loss occurs in high stage neuroblastoma without MYCN amplification. In SK-N-SH, CLB-Ga and GI-ME-N human neuroblastoma cells, stable ATM silencing promotes neuroblastoma progression in soft agar assays, and in subcutaneous xenografts in nude mice. This effect is dependent on the extent of ATM silencing and does not appear to involve MYCN. Our findings identify ATM as a potential haploinsufficient neuroblastoma tumor suppressor, whose inactivation mirrors the increased aggressiveness associated with 11q deletion in neuroblastoma. PMID:26053094

  10. Ataxia-telangiectasia mutated (ATM) silencing promotes neuroblastoma progression through a MYCN independent mechanism.

    PubMed

    Mandriota, Stefano J; Valentijn, Linda J; Lesne, Laurence; Betts, David R; Marino, Denis; Boudal-Khoshbeen, Mary; London, Wendy B; Rougemont, Anne-Laure; Attiyeh, Edward F; Maris, John M; Hogarty, Michael D; Koster, Jan; Molenaar, Jan J; Versteeg, Rogier; Ansari, Marc; Gumy-Pause, Fabienne

    2015-07-30

    Neuroblastoma, a childhood cancer with highly heterogeneous biology and clinical behavior, is characterized by genomic aberrations including amplification of MYCN. Hemizygous deletion of chromosome 11q is a well-established, independent marker of poor prognosis. While 11q22-q23 is the most frequently deleted region, the neuroblastoma tumor suppressor in this region remains to be identified. Chromosome bands 11q22-q23 contain ATM, a cell cycle checkpoint kinase and tumor suppressor playing a pivotal role in the DNA damage response. Here, we report that haploinsufficiency of ATM in neuroblastoma correlates with lower ATM expression, event-free survival, and overall survival. ATM loss occurs in high stage neuroblastoma without MYCN amplification. In SK-N-SH, CLB-Ga and GI-ME-N human neuroblastoma cells, stable ATM silencing promotes neuroblastoma progression in soft agar assays, and in subcutaneous xenografts in nude mice. This effect is dependent on the extent of ATM silencing and does not appear to involve MYCN. Our findings identify ATM as a potential haploinsufficient neuroblastoma tumor suppressor, whose inactivation mirrors the increased aggressiveness associated with 11q deletion in neuroblastoma. PMID:26053094

  11. Long noncoding RNAs and neuroblastoma

    PubMed Central

    Pandey, Gaurav Kumar; Kanduri, Chandrasekhar

    2015-01-01

    Neuroblastoma is a disease that affects infants and despite intense multimodal therapy, high-risk patients have low survival rates (<50%). In recent years long noncoding RNAs (lncRNAs) have become the cutting edge of cancer research with inroads made in understanding their roles in multiple cancer types, including prostate and breast cancers. The roles of lncRNAs in neuroblastoma have just begun to be elucidated. This review summarises where we are with regards to lncRNAs in neuroblastoma. The known mechanistic roles of lncRNAs during neuroblastoma pathogenesis are discussed, as well as the relationship between lncRNA expression and the differentiation capacity of neuroblastoma cells. We speculate about the use of some of these lncRNAs, such as those mapping to the 6p22 hotspot, as biomarkers for neuroblastoma prognosis and treatment. This novel way of thinking about both neuroblastoma and lncRNAs brings a new perspective to the prognosis and treatment of high-risk patients. PMID:26087192

  12. Structural differences between amyloid beta oligomers.

    PubMed

    Breydo, Leonid; Kurouski, Dmitry; Rasool, Suhail; Milton, Saskia; Wu, Jessica W; Uversky, Vladimir N; Lednev, Igor K; Glabe, Charles G

    2016-09-01

    In Alzheimer's disease, soluble Aβ oligomers are believed to play important roles in the disease pathogenesis, and their levels correlate with cognitive impairment. We have previously shown that Aβ oligomers can be categorized into multiple structural classes based on their reactivity with conformation-dependent antibodies. In this study, we analyzed the structures of Aβ40 oligomers belonging to two of these classes: fibrillar and prefibrillar oligomers. We found that fibrillar oligomers were similar in structure to fibrils but were less stable towards denaturation while prefibrillar oligomers were found to be partially disordered. These results are consistent with previously proposed structures for both oligomer classes while providing additional structural information. PMID:27363332

  13. Sequestration of toxic oligomers by HspB1 as a cytoprotective mechanism.

    PubMed

    Ojha, Juhi; Masilamoni, Gunasingh; Dunlap, David; Udoff, Ross A; Cashikar, Anil G

    2011-08-01

    Small heat shock proteins (sHsps) are molecular chaperones that protect cells from cytotoxic effects of protein misfolding and aggregation. HspB1, an sHsp commonly associated with senile plaques in Alzheimer's disease (AD), prevents the toxic effects of Aβ aggregates in vitro. However, the mechanism of this chaperone activity is poorly understood. Here, we observed that in two distinct transgenic mouse models of AD, mouse HspB1 (Hsp25) localized to the penumbral areas of plaques. We have demonstrated that substoichiometric amounts of human HspB1 (Hsp27) abolish the toxicity of Aβ oligomers on N2a (mouse neuroblastoma) cells. Using biochemical methods, spectroscopy, light scattering, and microscopy methods, we found that HspB1 sequesters toxic Aβ oligomers and converts them into large nontoxic aggregates. HspB1 was overexpressed in N2a cells in response to treatment with Aβ oligomers. Cultured neurons from HspB1-deficient mice were more sensitive to oligomer-mediated toxicity than were those from wild-type mice. Our results suggest that sequestration of oligomers by HspB1 constitutes a novel cytoprotective mechanism of proteostasis. Whether chaperone-mediated cytoprotective sequestration of toxic aggregates may bear clues to plaque deposition and may have potential therapeutic implications must be investigated in the future. PMID:21670152

  14. Prefibrillar transthyretin oligomers and cold stored native tetrameric transthyretin are cytotoxic in cell culture

    SciTech Connect

    Soergjerd, Karin; Klingstedt, Therese; Lindgren, Mikael; Kagedal, Katarina; Hammarstroem, Per

    2008-12-26

    Recent studies suggest that soluble, oligomeric species, which are intermediates in the fibril formation process in amyloid disease, might be the key species in amyloid pathogenesis. Soluble oligomers of human wild type transthyretin (TTR) were produced to elucidate oligomer properties. Employing ThT fluorescence, time-resolved fluorescence anisotropy of pyrene-labeled TTR, chemical cross-linking, and electron microscopy we demonstrated that early formed soluble oligomers (within minutes) from A-state TTR comprised on the average 20-30 TTR monomers. When administered to neuroblastoma cells these early oligomers proved highly cytotoxic and induced apoptosis after 48 h of incubation. More mature fibrils (>24 h of fibrillation) were non-toxic. Surprisingly, we also found that native tetrameric TTR, when purified and stored under cold conditions (4 deg. C) was highly cytotoxic. The effect could be partially restored by increasing the temperature of the protein. The cytotoxic effects of native tetrameric TTR likely stems from a hitherto unexplored low temperature induced rearrangement of the tetramer conformation that possibly is related to the conformation of misfolded TTR in amyloigogenic oligomers.

  15. Quantitative analysis of co-oligomer formation by amyloid-beta peptide isoforms

    NASA Astrophysics Data System (ADS)

    Iljina, Marija; Garcia, Gonzalo A.; Dear, Alexander J.; Flint, Jennie; Narayan, Priyanka; Michaels, Thomas C. T.; Dobson, Christopher M.; Frenkel, Daan; Knowles, Tuomas P. J.; Klenerman, David

    2016-06-01

    Multiple isoforms of aggregation-prone proteins are present under physiological conditions and have the propensity to assemble into co-oligomers with different properties from self-oligomers, but this process has not been quantitatively studied to date. We have investigated the amyloid-β (Aβ) peptide, associated with Alzheimer’s disease, and the aggregation of its two major isoforms, Aβ40 and Aβ42, using a statistical mechanical modelling approach in combination with in vitro single-molecule fluorescence measurements. We find that at low concentrations of Aβ, corresponding to its physiological abundance, there is little free energy penalty in forming co-oligomers, suggesting that the formation of both self-oligomers and co-oligomers is possible under these conditions. Our model is used to predict the oligomer concentration and size at physiological concentrations of Aβ and suggests the mechanisms by which the ratio of Aβ42 to Aβ40 can affect cell toxicity. An increased ratio of Aβ42 to Aβ40 raises the fraction of oligomers containing Aβ42, which can increase the hydrophobicity of the oligomers and thus promote deleterious binding to the cell membrane and increase neuronal damage. Our results suggest that co-oligomers are a common form of aggregate when Aβ isoforms are present in solution and may potentially play a significant role in Alzheimer’s disease.

  16. Quantitative analysis of co-oligomer formation by amyloid-beta peptide isoforms

    PubMed Central

    Iljina, Marija; Garcia, Gonzalo A.; Dear, Alexander J.; Flint, Jennie; Narayan, Priyanka; Michaels, Thomas C. T.; Dobson, Christopher M.; Frenkel, Daan; Knowles, Tuomas P. J.; Klenerman, David

    2016-01-01

    Multiple isoforms of aggregation-prone proteins are present under physiological conditions and have the propensity to assemble into co-oligomers with different properties from self-oligomers, but this process has not been quantitatively studied to date. We have investigated the amyloid-β (Aβ) peptide, associated with Alzheimer’s disease, and the aggregation of its two major isoforms, Aβ40 and Aβ42, using a statistical mechanical modelling approach in combination with in vitro single-molecule fluorescence measurements. We find that at low concentrations of Aβ, corresponding to its physiological abundance, there is little free energy penalty in forming co-oligomers, suggesting that the formation of both self-oligomers and co-oligomers is possible under these conditions. Our model is used to predict the oligomer concentration and size at physiological concentrations of Aβ and suggests the mechanisms by which the ratio of Aβ42 to Aβ40 can affect cell toxicity. An increased ratio of Aβ42 to Aβ40 raises the fraction of oligomers containing Aβ42, which can increase the hydrophobicity of the oligomers and thus promote deleterious binding to the cell membrane and increase neuronal damage. Our results suggest that co-oligomers are a common form of aggregate when Aβ isoforms are present in solution and may potentially play a significant role in Alzheimer’s disease. PMID:27346247

  17. Quantitative analysis of co-oligomer formation by amyloid-beta peptide isoforms.

    PubMed

    Iljina, Marija; Garcia, Gonzalo A; Dear, Alexander J; Flint, Jennie; Narayan, Priyanka; Michaels, Thomas C T; Dobson, Christopher M; Frenkel, Daan; Knowles, Tuomas P J; Klenerman, David

    2016-01-01

    Multiple isoforms of aggregation-prone proteins are present under physiological conditions and have the propensity to assemble into co-oligomers with different properties from self-oligomers, but this process has not been quantitatively studied to date. We have investigated the amyloid-β (Aβ) peptide, associated with Alzheimer's disease, and the aggregation of its two major isoforms, Aβ40 and Aβ42, using a statistical mechanical modelling approach in combination with in vitro single-molecule fluorescence measurements. We find that at low concentrations of Aβ, corresponding to its physiological abundance, there is little free energy penalty in forming co-oligomers, suggesting that the formation of both self-oligomers and co-oligomers is possible under these conditions. Our model is used to predict the oligomer concentration and size at physiological concentrations of Aβ and suggests the mechanisms by which the ratio of Aβ42 to Aβ40 can affect cell toxicity. An increased ratio of Aβ42 to Aβ40 raises the fraction of oligomers containing Aβ42, which can increase the hydrophobicity of the oligomers and thus promote deleterious binding to the cell membrane and increase neuronal damage. Our results suggest that co-oligomers are a common form of aggregate when Aβ isoforms are present in solution and may potentially play a significant role in Alzheimer's disease. PMID:27346247

  18. Targeting Cancer with Antisense Oligomers

    SciTech Connect

    Hnatowich, DJ

    2008-10-28

    With financial assistance from the Department of Energy, we have shown definitively that radiolabeled antisense DNAs and other oligomers will accumulate in target cancer cells in vitro and in vivo by an antisense mechanism. We have also shown that the number of mRNA targets for our antisense oligomers in the cancer cell types that we have investigated so far is sufficient to provide and antisense image and/or radiotherapy of cancer in mice. These studies have been reported in about 10 publications. However our observation over the past several years has shown that radiolabeled antisense oligomers administered intravenously in their native and naked form will accumulate and be retained in target xenografts by an antisense mechanism but will also accumulate at high levels in normal organs such as liver, spleen and kidneys. We have investigated unsuccessfully several commercially available vectors. Thus the use of radiolabeled antisense oligomers for the imaging of cancer must await novel approaches to delivery. This laboratory has therefore pursued two new paths, optical imaging of tumor and Auger radiotherapy. We are developing a novel method of optical imaging tumor using antisense oligomers with a fluorophore is administered while hybridized with a shorter complementary oligomer with an inhibitor. In culture and in tumored mice that the duplex remains intact and thus nonfluorescent until it encounters its target mRNA at which time it dissociates and the antisense oligomer binds along with its fluorophore to the target. Simultaneous with the above, we have also observed, as have others, that antisense oligomers migrate rapidly and quantitatively to the nucleus upon crossing cell membranes. The Auger electron radiotherapy path results from this observation since the nuclear migration properties could be used effectively to bring and to retain in the nucleus an Auger emitting radionuclide such as 111In or 125I bound to the antisense oligomer. Since the object becomes

  19. Neuroblastoma: diagnostic imaging and staging

    SciTech Connect

    Stark, D.D.; Moss, A.A.; Brasch, R.C.; deLorimier, A.A.; Albin, A.R.; London, D.A.; Gooding, C.A.

    1983-07-01

    Results of computed tomography (CT), scintigraphy, excretory urography, and other imaging tests used to diagnose and stage 38 cases of neuroblastoma prior to treatment were reviewed. Findings of these examinations were correlated with clinical data, laboratory data, results of biopsy, and surgical findings. CT was the most sensitive single test (100%) for the detection and delineation of the primary tumor. Calcifications that suggested the histologic diagnosis of neuroblastoma were present in 79% of the cases. Rim calcifications, the most specific pattern for neuroblastoma, were identified in 29% of all cases. CT alone accurately staged 82% of cases; when complemented by bone marrow biopsy, staging accuracy was 97%. CT alone was more accurate than any combination of imaging tests that excluded CT. An algorithm using CT is presented for the diagnosis and staging of neuroblastoma at reduced cost and with increased efficiency.

  20. What's New in Neuroblastoma Research and Treatment?

    MedlinePlus

    ... treatment Next Topic Additional resources for neuroblastoma What’s new in neuroblastoma research and treatment? Important research into ... cells different from normal cells may lead to new approaches to treating this disease. Newer drugs that ...

  1. Neuroblastoma: Molecular Pathogenesis and Therapy

    PubMed Central

    Louis, Chrystal U; Shohet, Jason M

    2015-01-01

    Neuroblastoma is a developmental tumor of young children arising from the embryonic sympathoadrenal lineage of the neural crest. Currently neuroblastoma is the primary cause of death from pediatric cancer for children between the age of 1 and 5 years and accounts for approximately 13% of all pediatric cancer mortality. Its clinical impact and its unique biology have made this aggressive malignancy the focus of a large concerted translational research effort. New insights into tumor biology are driving the development of new classification schemas; novel targeted therapeutic approaches include small molecule inhibitors, epigenetic, non-coding RNA, and cell-based immunologic therapies. Recent insights regarding the pathogenesis and biology of neuroblastoma will be placed in context with the current understanding of tumor biology and tumor/host interactions. Systematic classification of patients coupled with therapeutic advances point to a future of improved clinical outcomes for this biologically distinct and highly aggressive pediatric malignancy. PMID:25386934

  2. Neuroblastoma and Its Zebrafish Model.

    PubMed

    Zhu, Shizhen; Thomas Look, A

    2016-01-01

    Neuroblastoma, an important developmental tumor arising in the peripheral sympathetic nervous system (PSNS), accounts for approximately 10 % of all cancer-related deaths in children. Recent genomic analyses have identified a spectrum of genetic alterations in this tumor. Amplification of the MYCN oncogene is found in 20 % of cases and is often accompanied by mutational activation of the ALK (anaplastic lymphoma kinase) gene, suggesting their cooperation in tumor initiation and spread. Understanding how complex genetic changes function together in oncogenesis has been a continuing and daunting task in cancer research. This challenge was addressed in neuroblastoma by generating a transgenic zebrafish model that overexpresses human MYCN and activated ALK in the PSNS, leading to tumors that closely resemble human neuroblastoma and new opportunities to probe the mechanisms that underlie the pathogenesis of this tumor. For example, coexpression of activated ALK with MYCN in this model triples the penetrance of neuroblastoma and markedly accelerates tumor onset, demonstrating the interaction of these modified genes in tumor development. Further, MYCN overexpression induces adrenal sympathetic neuroblast hyperplasia, blocks chromaffin cell differentiation, and ultimately triggers a developmentally-timed apoptotic response in the hyperplastic sympathoadrenal cells. In the context of MYCN overexpression, activated ALK provides prosurvival signals that block this apoptotic response, allowing continued expansion and oncogenic transformation of hyperplastic neuroblasts, thus promoting progression to neuroblastoma. This application of the zebrafish model illustrates its value in rational assessment of the multigenic changes that define neuroblastoma pathogenesis and points the way to future studies to identify novel targets for therapeutic intervention. PMID:27165366

  3. Inconspicuous Presentation of Metastatic Neuroblastoma.

    PubMed

    Hatten, James; McGuffin, Aaron; Mogul, Mark

    2016-01-01

    Neuroblastoma is a malignant tumor arising from nerve tissue that accounts for approximately 15 percent of pediatric cancer fatalities. Primary tumors most commonly arise in sympathetic nervous tissue of the abdomen and metastasize to the bone marrow, liver, and lymph nodes. This case report depicts a 3-year-old girl who presented with a recurring fever, runny nose, and a positive test for rhinovirus suggesting a simple case of the common cold. Further investigation, however, revealed stage 4 neuroblastoma. This patient experience emphasizes the importance of having a high level of suspicion to rule out more serious underlying pathology in a seemingly unremarkable patient presentation. PMID:27491101

  4. Congenital neuroblastoma with placental involvement.

    PubMed

    Kume, Ayako; Morikawa, Teppei; Ogawa, Makiko; Yamashita, Aki; Yamaguchi, Shunichi; Fukayama, Masashi

    2014-01-01

    We describe an extremely rare case of congenital neuroblastoma with placental involvement. A fetus with a left abdominal mass detected during ultrasonography at 23 weeks' gestation developed hydrops fetalis by 26 weeks' gestation. The mother developed hypertension at 26 5/7 weeks' gestation. Based on a clinical diagnosis of pregnancy-induced hypertension, labor was induced at 26 6/7 weeks. However, intrauterine fetal death was diagnosed during delivery. Postmortern examination revealed a solid tumor at the site of the left adrenal gland. Histological examination of the tumor revealed dense proliferation of small round tumor cells with sparse cytoplasm and hyperchromatic nuclei. Some tumor-cell complexes contained abundant neurofibrils and Hormer-Wright rosettes were observed. A diagnosis of neuroblastoma of the left adrenal gland was made. The liver was markedly enlarged and was extensively replaced by neuroblastoma cells. In addition, small nests of tumor cells were detected in the blood vessels of various organs including the heart, lung, spleen, kidneys, stomach, small and large intestine, thyroid gland, testis, spinal cord, and bone marrow. Histological examination of the enlarged placenta revealed numerous neuroblastoma cells in the villous fetal capillary spaces. The present case was unusual in that the tumor cells were found not only in the chorionic villi, but also in the intervillous space of the maternal vascular system. However, there was no clinical evidence of maternal metastasis. PMID:25550872

  5. Primary orbital neuroblastoma with intraocular extension

    PubMed Central

    Vallinayagam, Muthukrishnan; Rao, Vasudev Anand; Pandian, Datta Gulnar; Akkara, John Davis; Ganesan, Niruban

    2015-01-01

    Neuroblastoma is an undifferentiated malignancy of primitive neuroblasts. Neuroblastoma is among the most common solid tumors of childhood. Orbital neuroblastoma is typically a metastatic tumor. In this case report, we describe a 2-year-old child with a rapidly progressing orbital tumor. Computed tomography revealed an orbital mass lesion with extraocular and intraocular components. An incisional biopsy was done, and a histopathological examination showed features suggestive of neuroblastoma. Systemic workup including ultrasonography of the abdomen, chest roentgenogram, whole body computed tomography, and bone scintigraphy showed no evidence of systemic involvement. The diagnosis of primary orbital neuroblastoma was made, and the child was subjected to chemotherapy followed by rapid melting of the tumor. Neuroblastoma should be considered in the differential diagnosis of childhood orbital tumors. PMID:26576531

  6. The "neuro" of neuroblastoma: Neuroblastoma as a neurodevelopmental disorder.

    PubMed

    Ratner, Nancy; Brodeur, Garrett M; Dale, Russell C; Schor, Nina F

    2016-07-01

    Neuroblastoma is a childhood cancer derived from cells of neural crest origin. The hallmarks of its enigmatic character include its propensity for spontaneous regression under some circumstances and its association with paraneoplastic opsoclonus, myoclonus, and ataxia. The neurodevelopmental underpinnings of its origins may provide important clues for development of novel therapeutic and preventive agents for this frequently fatal malignancy and for the associated paraneoplastic syndromes. Ann Neurol 2016;80:13-23. PMID:27043043

  7. Paraneoplastic syndromes in olfactory neuroblastoma

    PubMed Central

    Gabrych, Anna; Czapiewski, Piotr; Sworczak, Krzysztof

    2015-01-01

    Olfactory neuroblastoma (ONB) is a rare malignant neoplasm of sinonasal tract, derived from olfactory epithelium. Unilateral nasal obstruction, epistaxis, sinusitis, and headaches are common symptoms. Olfactory neuroblastoma shows neuroendocrine differentiation and similarly to other neuroendocrine tumors can produce several types of peptic substances and hormones. Excess production of these substances can be responsible for different types of endocrinological paraneoplastic syndromes (PNS). Moreover, besides endocrinological, in ONB may also occur neurological PNS, caused by immune cross-reactivity between tumor and normal host tissues in the nervous system. Paraneoplastic syndromes in ONB include: syndrome of inappropriate ADH secretion (SIADH), ectopic ACTH syndrome (EAS), humoral hypercalcemia of malignancy (HHM), hypertension due to catecholamine secretion by tumor, opsoclonus-myoclonus-ataxia (OMA) and paraneoplastic cerebellar degeneration. Paraneoplastic syndromes in ONB tend to have atypical features, therefore diagnosis may be difficult. In this review, we described initial symptoms, patterns of presentation, treatment and outcome of paraneoplastic syndromes in ONB, reported in the literature. PMID:26199564

  8. [Cervical neuroblastoma in an infant].

    PubMed

    Arvai, Krisztina; Tóth, Judit; Németh, Tamás; Kiss, Csongor; Molnár, Péter; Oláh, Eva

    2004-01-01

    The case of a one-month-old patient admitted to the Department of Pediatrics (Medical and Health Science Center, Debrecen University) because of respiratory distress caused by a cervical mass compressing the upper respiratory pathways is presented. The mass could only be partially removed, the histological diagnosis proved to be neuroblastoma (SBCT: "small blue cell tumor"). Despite the fact that the DNA index of tumor cells (ploidy measurements) and the age of the patient suggested a favourable prognosis, the tumor continued to grow and metastases appeared. Because of symptoms of compression exerted on the respiratory system by the tumor, chemotherapy had to be applied. Since a standard OPEC/OJEC chemotherapeutic protocol proved to be not entirely effective and a residual tumor was still present, retinoic acid and interferon treatment was introduced. Presently, 4 years after the diagnosis, the patient is in complete remission and can be considered to be cured. The case presented here demonstrates that despite the favorable prognosis of the majority of infant neuroblastomas, in some cases the anatomic location of the tumor, leading to disturbance of vital functions, may serve as indication of chemotherapy. Our experience also proved the efficacy of retinoic acid and interferon treatment in relapsed neuroblastoma. PMID:15105902

  9. Sublethal irradiation promotes invasiveness of neuroblastoma cells

    SciTech Connect

    Schweigerer, Lothar; Rave-Fraenk, Margret; Schmidberger, Heinz; Hecht, Monica . E-mail: monica.hecht@med.uni-goettingen.de

    2005-05-13

    Neuroblastoma is the most frequent extracranial solid tumour of childhood. Despite multiple clinical efforts, clinical outcome has remained poor. Neuroblastoma is considered to be radiosensitive, but some clinical studies including the German trial NB90 failed to show a clinical benefit of radiation therapy. The mechanisms underlying this apparent discrepancy are still unclear. We have therefore investigated the effects of radiation on neuroblastoma cell behaviour in vitro. We show that sublethal doses of irradiation up-regulated the expression of the hepatocyte growth factor (HGF) and its receptor c-Met in some neuroblastoma cell lines. The increase in HGF/c-Met expression was correlated with enhanced invasiveness and activation of proteases degrading the extracellular matrix. Thus, irradiation at sublethal doses may promote the metastatic dissemination of neuroblastoma cells through activating the HGF/c-Met pathway and triggering matrix degradation.

  10. The effect of explosive blast loading on human neuroblastoma cells.

    PubMed

    Zander, Nicole E; Piehler, Thuvan; Banton, Rohan; Boggs, Mary

    2016-07-01

    Diagnosis of mild to moderate traumatic brain injury is challenging because brain tissue damage progresses slowly and is not readily detectable by conventional imaging techniques. We have developed a novel in vitro model to study primary blast loading on dissociated neurons using nitroamine explosives such as those used on the battlefield. Human neuroblastoma cells were exposed to single and triple 50-psi explosive blasts and single 100-psi blasts. Changes in membrane permeability and oxidative stress showed a significant increase for the single and triple 100-psi blast conditions compared with single 50-psi blast and controls. PMID:27033003

  11. Role of radiation therapy in the treatment of olfactory neuroblastoma

    SciTech Connect

    Ahmad, K.; Fayos, J.V.

    1980-03-01

    Nine patients with olfactory neuroblastoma were treated at the Radiation Therapy Service of the University of Michigan Medical Center (UMMC); their case histories are presented. There was a slight female predominance and the peak age distribution was between 60 to 69 years (4 patients). One patient developed sudden visual loss in one eye and partial loss in the other resulting from a hematoma at the optic chiasmal region. We have ascribed it to radiation damage. Our results show that this tumor is radiocontrollable; control at primary site occurs in 66.6% of patients. We recommend postoperative irradiation in all tumors that are extensive initially.

  12. How does ethanol induce apoptotic cell death of SK-N-SH neuroblastoma cells.

    PubMed

    Moon, Yong; Kwon, Yongil; Yu, Shun

    2013-07-15

    A body of evidence suggests that ethanol can lead to damage of neuronal cells. However, the mechanism underlying the ethanol-induced damage of neuronal cells remains unclear. The role of mitogen-activated protein kinases in ethanol-induced damage was investigated in SK-N-SH neuroblastoma cells. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide cell viability assay, DNA fragmentation detection, and flow cytometric analysis showed that ethanol induced apoptotic cell death and cell cycle arrest, characterized by increased caspase-3 activity, DNA fragmentation, nuclear disruption, and G1 arrest of cell cycle of the SK-N-SH neuroblastoma cells. In addition, western blot analysis indicated that ethanol induced a lasting increase in c-Jun N-terminal protein kinase activity and a transient increase in p38 kinase activity of the neuroblastoma cells. c-Jun N-terminal protein kinase or p38 kinase inhibitors significantly reduced the ethanol-induced cell death. Ethanol also increased p53 phosphorylation, followed by an increase in p21 tumor suppressor protein and a decrease in phospho-Rb (retinoblastoma) protein, leading to alterations in the expressions and activity of cyclin dependent protein kinases. Our results suggest that ethanol mediates apoptosis of SK-N-SH neuroblastoma cells by activating p53-related cell cycle arrest possibly through activation of the c-Jun N-terminal protein kinase-related cell death pathway. PMID:25206494

  13. Olfactory Neuroblastoma: A Case Report.

    PubMed

    Olmo, Heather R; Stokes, Steven Marc; Foss, Robert D

    2016-06-01

    A 43-year-old female presented with persistent nasal congestion with intermittent epistaxis without resolution for the preceding 5 years. Clinical examination revealed a large pink rubbery mass, medial to the middle turbinate in the right nasal cavity extending to the choana. Radiographic images demonstrated a heterogeneously enhancing lobular soft tissue mass filling the right nasal cavity, causing lateral bowing of the right medial orbital wall and extending posteriorly to the right anterior ethmoid sinus. The clinical, radiographic, histologic, and immunohistochemical features of olfactory neuroblastoma are discussed. PMID:26316323

  14. Ballistic Energy Transport in Oligomers.

    PubMed

    Rubtsova, Natalia I; Qasim, Layla N; Kurnosov, Arkady A; Burin, Alexander L; Rubtsov, Igor V

    2015-09-15

    The development of nanocomposite materials with desired heat management properties, including nanowires, layered semiconductor structures, and self-assembled monolayer (SAM) junctions, attracts broad interest. Such materials often involve polymeric/oligomeric components and can feature high or low thermal conductivity, depending on their design. For example, in SAM junctions made of alkane chains sandwiched between metal layers, the thermal conductivity can be very low, whereas the fibers of ordered polyethylene chains feature high thermal conductivity, exceeding that of many pure metals. The thermal conductivity of nanostructured materials is determined by the energy transport between and within each component of the material, which all need to be understood for optimizing the properties. For example, in the SAM junctions, the energy transport across the metal-chain interface as well as the transport through the chains both determine the overall heat conductivity, however, to separate these contributions is difficult. Recently developed relaxation-assisted two-dimensional infrared (RA 2DIR) spectroscopy is capable of studying energy transport in individual molecules in the time domain. The transport in a molecule is initiated by exciting an IR-active group (a tag); the method records the influence of the excess energy on another mode in the molecule (a reporter). The energy transport time can be measured for different reporters, and the transport speed through the molecule is evaluated. Various molecules were interrogated by RA 2DIR: in molecules without repeating units (disordered), the transport mechanism was expected and found to be diffusive. The transport via an oligomer backbone can potentially be ballistic, as the chain offers delocalized vibrational states. Indeed, the transport regime via three tested types of oligomers, alkanes, polyethyleneglycols, and perfluoroalkanes was found to be ballistic, whereas the transport within the end groups was diffusive

  15. Cytopathogenicity of Naegleria for cultured neuroblastoma cells

    SciTech Connect

    Fulford, D.E.

    1985-01-01

    The cytopathic activity of live Naegleria amoebae and cell-free lysates of Naegleria for B-103 rat neuroblastoma cells was investigated using a /sup 51/Cr release assay. Live amoebae and cell-free lysates of N. fowleri, N. australiensis, N. lovaniensis, and N. gruberi all induced sufficient damage to radiolabeled B-103 cells to cause a significant release of chromium. The cytotoxic activity present in the cell-free lysates of N. fowleri can be recovered in the supernatant fluid following centrifugation at 100,000xg and precipitation of the 100,000xg supernatant fluid with ammonium sulfate. Initial characterization of the cytotoxic factor indicates that it is a heat labile, pH sensitive, soluble protein. The cytotoxic activity is abolished by either extraction, unaffected by repeated freeze-thawing, and is not sensitive to inhibitors of proteolytic enzymes. Phospholipase A activity was detected in the cytotoxic ammonium sulfate precipitable material, suggesting that this enzyme activity may have a role in the cytotoxic activity of the cell-free lysates.

  16. HIV-1 propagates in human neuroblastoma cells.

    PubMed

    Shapshak, P; Sun, N C; Resnick, L; Thornthwaite, J T; Schiller, P; Yoshioka, M; Svenningsson, A; Tourtellotte, W W; Imagawa, D T

    1991-01-01

    A major question in the pathogenesis of AIDS encephalopathy and dementia is whether HIV-1 directly infects cells of the central nervous system (CNS). The propagation of HIV was attempted in six cell lines: three related and three unrelated to the nervous system. HIV was able to propagate in two human neuroblastoma cell lines and a lymphocytic cell line control but did not result in infections of African green monkey kidney cells, human cervix carcinoma cells, and one human brain astrocytoma cell line. Neuroblastoma cell lines infected with HIV showed peaks of reverse transcriptase activity at 10-14 days postinfection. After prolonged growth in cell cultures, one of the neuroblastoma cell lines showed multiphasic virus production, additional high peaks of reverse transcriptase activity, 20-fold greater than the first, lasting from 36 to 74 days and 110 to 140 days postinfection. The presence of HIV was confirmed by p24 antigen capture. The neuroblastoma cell lines had weak but detectable levels of CD4 immunoreactivity by immunoperoxidase and flow immunocytometric analysis. Although no T4-specific RNA sequences were detected by hybridization of Northern blots of total and poly A-selected RNA extracted from the two neuroblastoma cell lines by using a T4 specific complimentary DNA probe, monoclonal antibodies to the CD4 receptor blocked HIV infection in both neuroblastoma cell lines. Thus, the infection of neuroblastoma cells by HIV occurs in part by a CD4-dependent mechanism. Passaging the neuroblastoma cell lines weekly and bimonthly resulted in similar cell cycle-DNA content patterns for the more permissive cell line and with significant numbers of cells in the S phase. HIV-infected neuroblastoma cell lines provide an in vitro model for the evaluation of virus-host cell interactions and may be useful in addressing the issue of the persistence of HIV in the human CNS. PMID:1704060

  17. Neuroblastoma: A Tough Nut to Crack.

    PubMed

    Speleman, Frank; Park, Julie R; Henderson, Tara O

    2016-01-01

    Neuroblastoma, an embryonal tumor arising from neural crest-derived progenitor cells, is the most common solid tumor in childhood, with more than 700 cases diagnosed per year in the United States. In the past several decades, significant advances have been made in the treatment of neuroblastoma. Treatment advances reflect improved understanding of the biology of neuroblastoma. Although amplification of MYCN was discovered in the early 1980s, our understanding of neuroblastoma oncogenesis has advanced in the last decade as a result of high-throughput genomic analysis, exome and whole-genome sequencing, genome-wide association studies, and synthetic lethal drug screens. Our refined understanding of neuroblastoma biology and genetics is reflected in improved prognostic stratification and appropriate tailoring of therapy in recent clinical trials. Moreover, for high-risk neuroblastoma, a disease that was uniformly fatal 3 decades ago, recent clinical trials incorporating autologous hematopoietic transplant and immunotherapy utilizing anti-GD2 antibody plus cytokines have shown improved event-free and overall survival. These advances have resulted in a growing population of long-term survivors of neuroblastoma. Examination of the late effects and second malignant neoplasms (SMNs) in both older generations of survivors and more recently treated survivors will inform both design of future trials and surveillance guidelines for long-term follow-up. As a consequence of advances in understanding of the biology of neuroblastoma, successful clinical trials, and refined understanding of the late effects and SMNs of survivors, the promise of precision medicine is becoming a reality for patients with neuroblastoma. PMID:27249766

  18. Human fetal neuroblast and neuroblastoma transcriptome analysis confirms neuroblast origin and highlights neuroblastoma candidate genes

    PubMed Central

    De Preter, Katleen; Vandesompele, Jo; Heimann, Pierre; Yigit, Nurten; Beckman, Siv; Schramm, Alexander; Eggert, Angelika; Stallings, Raymond L; Benoit, Yves; Renard, Marleen; Paepe, Anne De; Laureys, Geneviève; Påhlman, Sven; Speleman, Frank

    2006-01-01

    Background Neuroblastoma tumor cells are assumed to originate from primitive neuroblasts giving rise to the sympathetic nervous system. Because these precursor cells are not detectable in postnatal life, their transcription profile has remained inaccessible for comparative data mining strategies in neuroblastoma. This study provides the first genome-wide mRNA expression profile of these human fetal sympathetic neuroblasts. To this purpose, small islets of normal neuroblasts were isolated by laser microdissection from human fetal adrenal glands. Results Expression of catecholamine metabolism genes, and neuronal and neuroendocrine markers in the neuroblasts indicated that the proper cells were microdissected. The similarities in expression profile between normal neuroblasts and malignant neuroblastomas provided strong evidence for the neuroblast origin hypothesis of neuroblastoma. Next, supervised feature selection was used to identify the genes that are differentially expressed in normal neuroblasts versus neuroblastoma tumors. This approach efficiently sifted out genes previously reported in neuroblastoma expression profiling studies; most importantly, it also highlighted a series of genes and pathways previously not mentioned in neuroblastoma biology but that were assumed to be involved in neuroblastoma pathogenesis. Conclusion This unique dataset adds power to ongoing and future gene expression studies in neuroblastoma and will facilitate the identification of molecular targets for novel therapies. In addition, this neuroblast transcriptome resource could prove useful for the further study of human sympathoadrenal biogenesis. PMID:16989664

  19. Pediatric neuroblastomas: genetic and epigenetic 'danse macabre'.

    PubMed

    van Noesel, Max M; Versteeg, Rogier

    2004-01-21

    Neuroblastomas are the most frequently occurring solid tumors in children under 5 years. Spontaneous regression is more common in neuroblastomas than in any other tumor type, especially in young patients under 12 months. Unfortunately, the full clinical spectrum of neuroblastomas also includes very aggressive tumors, unresponsive to multi-modality treatment and accounting for most of the pediatric cancer mortalities under 5 years of age. It is generally emphasized that more than one biological entity of neuroblastoma exists. Structural genetic defects such as amplification of MYCN, gain of chromosome 17q and LOH of 1p and several other chromosomal regions have proven to be valuable as prognostic factors and will be discussed in relation to their clinical relevance. Recent research is starting to uncover important molecular pathways involved in the pathogenesis of neuroblastomas. The aim of this review is to discuss several important aspects of the biology of the neuroblast, such as the role of overexpressed oncogenes like MYCN and cyclin D1, the mechanisms leading to decreased apoptosis, like overexpression of BCL-2, survivin, NM23, epigenetic silencing of caspase 8 and the role of tumor suppressor genes, like p53, p73 and RASSF1A. In addition, the role of specific proteins overexpressed in neuroblastomas, such as the neurotrophin receptors TrkA, B and C in relation to spontaneous regression and anti-angiogenesis will be discussed. Finally, we will try to relate these pathways to the embryonal origin of neuroblastomas and discuss possible new avenues in the therapeutic approach of future neuroblastoma patients. PMID:14697505

  20. Structural Insight into Proteorhodopsin Oligomers

    PubMed Central

    Stone, Katherine M.; Voska, Jeda; Kinnebrew, Maia; Pavlova, Anna; Junk, Matthias J.N.; Han, Songi

    2013-01-01

    Oligomerization has important functional implications for many membrane proteins. However, obtaining structural insight into oligomeric assemblies is challenging, as they are large and resist crystallization. We focus on proteorhodopsin (PR), a protein with seven transmembrane α-helices that was found to assemble to hexamers in densely packed lipid membrane, or detergent-solubilized environments. Yet, the structural organization and the subunit interface of these PR oligomers were unknown. We used site-directed spin-labeling together with electron spin-resonance lineshape and Overhauser dynamic nuclear polarization analysis to construct a model for the specific orientation of PR subunits within the hexameric complex. We found intersubunit distances to average 16 Å between neighboring 55 residues and that residues 177 are >20 Å apart from each other. These distance constraints show that PR has a defined and radial orientation within a hexamer, with the 55-site of the A-B loop facing the hexamer core and the 177-site of the E-F loop facing the hexamer exterior. Dynamic nuclear polarization measurements of the local solvent dynamics complement the electron spin-resonance-based distance analysis, by resolving whether protein surfaces at positions 55, 58, and 177 are exposed to solvent, or covered by protein-protein or protein-detergent contacts. PMID:23442869

  1. Induced differentiation inhibits sphere formation in neuroblastoma.

    PubMed

    Craig, Brian T; Rellinger, Eric J; Alvarez, Alexandra L; Dusek, Haley L; Qiao, Jingbo; Chung, Dai H

    2016-08-19

    Neuroblastoma arises from the neural crest, the precursor cells of the sympathoadrenal axis, and differentiation status is a key prognostic factor used for clinical risk group stratification and treatment strategies. Neuroblastoma tumor-initiating cells have been successfully isolated from patient tumor samples and bone marrow using sphere culture, which is well established to promote growth of neural crest stem cells. However, accurate quantification of sphere-forming frequency of commonly used neuroblastoma cell lines has not been reported. Here, we show that MYCN-amplified neuroblastoma cell lines form spheres more frequently than non-MYCN-amplified cell lines. We also show that sphere formation is directly sensitive to cellular differentiation status. 13-cis-retinoic acid is a clinically used differentiating agent that induces a neuronal phenotype in neuroblastoma cells. Induced differentiation nearly completely blocked sphere formation. Furthermore, sphere formation was specifically FGF-responsive and did not respond to increasing doses of EGF. Taken together, these data suggest that sphere formation is an accurate method of quantifying the stemness phenotype in neuroblastoma. PMID:27297102

  2. Olfactory neuroblastoma: A case report

    PubMed Central

    USLU, GONCA HANEDAN; CANYILMAZ, EMINE; ZENGIN, AHMET YASAR; MUNGAN, SEVDEGUL; YONEY, ADNAN; BAHADIR, OSMAN; GOCMEZ, HUSEYIN

    2015-01-01

    Olfactory neuroblastoma (ON) is a rare type of malignant neoplasm originating from the olfactory neuroepithelial cells of the nasal cavity. ON is also known as esthesioneuroblastoma or neuroendocrine carcinoma. The malignancy accounts for <3% of tumors originating in the nasal cavity. Through the nasal cavity, ON may infiltrate the sinuses, the orbit and the cranium. The tumor is characterized by a pattern of slow growth and local recurrences. Treatment options are surgical excision or surgery combined with a radiotherapy (RT) and/or chemotherapy combination treatment. The present study reports the case of a 69-year-old patient with a mass in the nasal cavity who was treated by combined surgical excision and RT. The literature for ON and the treatment of the tumor are also discussed. PMID:26788185

  3. Apoptotic Cell Death in Neuroblastoma

    PubMed Central

    Li, Yuanyuan; Nakagawara, Akira

    2013-01-01

    Neuroblastoma (NB) is one of the most common malignant solid tumors in childhood, which derives from the sympathoadrenal lineage of the neural crest and exhibits extremely heterogeneous biological and clinical behaviors. The infant patients frequently undergo spontaneous regression even with metastatic disease, whereas the patients of more than one year of age who suffer from disseminated disease have a poor outcome despite intensive multimodal treatment. Spontaneous regression in favorable NBs has been proposed to be triggered by nerve growth factor (NGF) deficiency in the tumor with NGF dependency for survival, while aggressive NBs have defective apoptotic machinery which enables the tumor cells to evade apoptosis and confers the resistance to treatment. This paper reviews the molecules and pathways that have been recently identified to be involved in apoptotic cell death in NB and discusses their potential prospects for developing more effective therapeutic strategies against aggressive NB. PMID:24709709

  4. Nanopore formation in neuroblastoma cells following ultrashort electric pulse exposure

    NASA Astrophysics Data System (ADS)

    Roth, Caleb C.; Payne, Jason A.; Wilmink, Gerald J.; Ibey, Bennett L.

    2011-03-01

    Ultrashort or nanosecond electrical pulses (USEP) cause repairable damage to the plasma membranes of cells through formation of nanopores. These nanopores are able to pass small ions such as sodium, calcium, and potassium, but remain impermeable to larger molecules like trypan blue and propidium iodide. What remains uncertain is whether generation of nanopores by ultrashort electrical pulses can inhibit action potentials in excitable cells. In this paper, we explored the sensitivity of excitable cells to USEP using Calcium Green AM 1 ester fluorescence to measure calcium uptake indicative of nanopore formation in the plasma membrane. We determined the threshold for nanopore formation in neuroblastoma cells for three pulse parameters (amplitude, pulse width, and pulse number). Measurement of such thresholds will guide future studies to determine if USEP can inhibit action potentials without causing irreversible membrane damage.

  5. Neuroblastoma

    MedlinePlus

    ... High-dose chemotherapy, followed by autologous stem cell transplantation , is being studied for use in children with ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  6. Diagnosis and treatment of neuroblastoma using metaiodobenzylguanidine

    SciTech Connect

    Edeling, C.J.; Frederiksen, P.B.; Kamper, J.; Jeppesen, P.

    1987-08-01

    Neuroblastoma is a lethal and not uncommon tumor in childhood. Early detection and display of the spread of the tumor is highly desirable for proper treatment. Nine children suspected of having neuroblastomas were examined by I-131 metaiodobenzylguanidine (I-131 MIBG) imaging. In two recent studies I-123 metaiodobenzylguanidine (I-123 MIBG) was used. A primary adrenal neuroblastoma was correctly identified in three cases. In two patients additional tumor sites were found. In one patient, who was in complete remission, no pathologic accumulation of I-131 MIBG was found. I-131 MIBG images were also normal in four patients with other types of neoplastic diseases. A boy with multiple metastases was treated with 100 mCi of I-131 MIBG. He developed transient gastrointestinal illness and there was no regression of the tumor deposits. In one girl with a large adrenal neuroblastoma high uptake of I-131 MIBG was observed. She received two therapy doses of I-131 MIBG (35 mCi and 75 mCi) with curative intention giving a total absorbed dose in the tumor of approximately 76 Gy. In spite of high retention of radioactivity in the tumor, regression did not occur, but her general condition was improved. In the present study, images of superior quality were obtained with I-123 MIBG imaging. It is concluded that imaging using I-131 MIBG or I-123 MIBG should be used in both the initial evaluation and the follow-up of children with neuroblastoma.

  7. Nucleolar protein PES1 is a marker of neuroblastoma outcome and is associated with neuroblastoma differentiation

    PubMed Central

    Nakaguro, Masato; Kiyonari, Shinichi; Kishida, Satoshi; Cao, Dongliang; Murakami-Tonami, Yuko; Ichikawa, Hitoshi; Takeuchi, Ichiro; Nakamura, Shigeo; Kadomatsu, Kenji

    2015-01-01

    Neuroblastoma (NB) is a childhood malignant tumor that arises from precursor cells of the sympathetic nervous system. Spontaneous regression is a phenomenon unique to NBs and is caused by differentiation of tumor cells. PES1 is a multifunctional protein with roles in both neural development and ribosome biogenesis. Various kinds of models have revealed the significance of PES1 in neurodevelopment. However, the roles of PES1 in NB tumorigenesis and differentiation have remained unknown. Here we show that NB cases with MYCN amplification and clinically unfavorable stage (INSS stage 4) express higher levels of PES1. High PES1 expression was associated with worse overall and relapse-free survival. In NB cell lines, PES1 knockdown suppressed tumor cell growth and induced apoptosis. This growth inhibition was associated with the expression of NB differentiation markers. However, when the differentiation of NB cell lines was induced by the use of all-trans retinoic acid, there was a corresponding decrease in PES1 expression. Pes1 expression of tumorspheres originated from MYCN transgenic mice also diminished after the induction of differentiation with growth factors. We also reanalyzed the distribution of PES1 in the nucleolus. PES1 was localized in the dense fibrillar component, but not in the granular component of nucleoli. After treatment with the DNA-damaging agent camptothecin, this distribution was dramatically changed to diffuse nucleoplasmic. These data suggest that PES1 is a marker of NB outcome, that it regulates NB cell proliferation, and is associated with NB differentiation. PMID:25557119

  8. Incomplete pneumolysin oligomers form membrane pores.

    PubMed

    Sonnen, Andreas F-P; Plitzko, Jürgen M; Gilbert, Robert J C

    2014-01-01

    Pneumolysin is a member of the cholesterol-dependent cytolysin (CDC) family of pore-forming proteins that are produced as water-soluble monomers or dimers, bind to target membranes and oligomerize into large ring-shaped assemblies comprising approximately 40 subunits and approximately 30 nm across. This pre-pore assembly then refolds to punch a large hole in the lipid bilayer. However, in addition to forming large pores, pneumolysin and other CDCs form smaller lesions characterized by low electrical conductance. Owing to the observation of arc-like (rather than full-ring) oligomers by electron microscopy, it has been hypothesized that smaller oligomers explain smaller functional pores. To investigate whether this is the case, we performed cryo-electron tomography of pneumolysin oligomers on model lipid membranes. We then used sub-tomogram classification and averaging to determine representative membrane-bound low-resolution structures and identified pre-pores versus pores by the presence of membrane within the oligomeric curve. We found pre-pore and pore forms of both complete (ring) and incomplete (arc) oligomers and conclude that arc-shaped oligomeric assemblies of pneumolysin can form pores. As the CDCs are evolutionarily related to the membrane attack complex/perforin family of proteins, which also form variably sized pores, our findings are of relevance to that class of proteins as well. PMID:24759615

  9. Monoclonal Antibody Therapy for Advanced Neuroblastoma

    Cancer.gov

    NCI is sponsoring two clinical trials of a monoclonal antibody called ch14.18, in combination with other drugs, to see if the antibody may be helpful for children or young adults (up to age 21) with relapsed or refractory neuroblastoma.

  10. MIBG in Neuroblastoma Diagnostic Imaging and Therapy.

    PubMed

    Sharp, Susan E; Trout, Andrew T; Weiss, Brian D; Gelfand, Michael J

    2016-01-01

    Neuroblastoma is a common malignancy observed in infants and young children. It has a varied prognosis, ranging from spontaneous regression to aggressive metastatic tumors with fatal outcomes despite multimodality therapy. Patients are divided into risk groups on the basis of age, stage, and biologic tumor factors. Multiple clinical and imaging tests are needed for accurate patient assessment. Iodine 123 ((123)I) metaiodobenzylguanidine (MIBG) is the first-line functional imaging agent used in neuroblastoma imaging. MIBG uptake is seen in 90% of neuroblastomas, identifying both the primary tumor and sites of metastatic disease. The addition of single photon emission computed tomography (SPECT) and SPECT/computed tomography to (123)I-MIBG planar images can improve identification and characterization of sites of uptake. During scan interpretation, use of MIBG semiquantitative scoring systems improves description of disease extent and distribution and may be helpful in defining prognosis. Therapeutic use of MIBG labeled with iodine 131 ((131)I) is being investigated as part of research trials, both as a single agent and in conjunction with other therapies. (131)I-MIBG therapy has been studied in patients with newly diagnosed neuroblastoma and those with relapsed disease. Development and implementation of an institutional (131)I-MIBG therapy research program requires extensive preparation with a focus on radiation protection. PMID:26761540

  11. Symmetry breaking in human neuroblastoma cells.

    PubMed

    Izumi, Hideki; Kaneko, Yasuhiko

    2014-01-01

    Asymmetric cell division (ACD) is a characteristic of cancer stem cells, which exhibit high malignant potential. However, the cellular mechanisms that regulate symmetric (self-renewal) and asymmetric cell divisions are mostly unknown. Using human neuroblastoma cells, we found that the oncosuppressor protein tripartite motif containing 32 (TRIM32) positively regulates ACD. PMID:27308367

  12. Symmetry breaking in human neuroblastoma cells

    PubMed Central

    Izumi, Hideki; Kaneko, Yasuhiko

    2014-01-01

    Asymmetric cell division (ACD) is a characteristic of cancer stem cells, which exhibit high malignant potential. However, the cellular mechanisms that regulate symmetric (self-renewal) and asymmetric cell divisions are mostly unknown. Using human neuroblastoma cells, we found that the oncosuppressor protein tripartite motif containing 32 (TRIM32) positively regulates ACD. PMID:27308367

  13. Unlikely suspects identified in neuroblastoma conspiracy.

    PubMed

    Bernards, Rene

    2014-04-01

    KIF1B is a candidate tumor-suppressor gene in neuroblastoma whose function is to mediate apoptosis when nerve growth factor becomes limiting in the developing nervous system. Chen and colleagues now provide mechanistic insight into how one of the protein products of this locus, KIF1Bβ, induces apoptosis. PMID:24706657

  14. The Effect of Molecular Weight on the Composite Properties of Cured Phenylethynyl Terminated Imide Oligomers

    NASA Technical Reports Server (NTRS)

    Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.

    1997-01-01

    As part of a program to develop high temperature/high performance structural resins for aeronautical applications, imide oligomers containing terminal phenylethynyl groups with calculated number average molecular weights of 1250, 2500 and 5000 g/mol were prepared, characterized, and evaluated as adhesives and composite matrix resins. The goal of this work was to develop resin systems that are processable using conventional processing equipment into void free composites that exhibit high mechanical properties with long term high temperature durability, and are not affected by exposure to common aircraft fluids. The imide oligomers containing terminal phenylethynyl groups were fabricated into titanium adhesive specimens and IM-7 carbon fiber laminates under 0.1 - 1.4 MPa for 1 hr at 350-371 C. The lower molecular weight oligomers exhibited higher cured Tg, better processability, and better retention of mechanical properties at elevated temperature without significantly sacrificing toughness or damage tolerance than the higher molecular weight oligomer. The neat resin, adhesive and composite properties of the cured polymers will be presented.

  15. Pharmacological inhibition of Rho-kinase (ROCK) signaling enhances cisplatin resistance in neuroblastoma cells.

    PubMed

    Street, Catharine A; Routhier, Alissa A; Spencer, Carrie; Perkins, Ashley L; Masterjohn, Katherine; Hackathorn, Alexander; Montalvo, John; Dennstedt, Emily A; Bryan, Brad A

    2010-11-01

    The role of the RhoA/Rho kinase (ROCK) signaling pathway in cell survival remains a very controversial issue, with its activation being pro-apoptotic in many cell types and anti-apoptotic in others. To test if ROCK inhibition contributes to tumor cell survival or death following chemotherapy, we treated cisplatin damaged neuroblastoma cells with a pharmacological ROCK inhibitor (Y27632) or sham, and monitored cell survival, accumulation of a chemoresistant phenotype, and in vivo tumor formation. Additionally, we assayed if ROCK inhibition altered the expression of genes known to be involved in cisplatin resistance. Our studies indicate that ROCK inhibition results in increased cell survival, acquired chemoresistance, and enhanced tumor survival following cisplatin cytotoxicity, due in part to altered expression of cisplatin resistance genes. These findings suggest that ROCK inhibition in combination with cisplatin chemotherapy may lead to enhanced tumor chemoresistance in neuroblastoma. PMID:20878077

  16. Pharmacological inhibition of Rho-kinase (ROCK) signaling enhances cisplatin resistance in neuroblastoma cells

    PubMed Central

    STREET, CATHARINE A.; ROUTHIER, ALISSA A.; SPENCER, CARRIE; PERKINS, ASHLEY L.; MASTERJOHN, KATHERINE; HACKATHORN, ALEXANDER; MONTALVO, JOHN; DENNSTEDT, EMILY A.; BRYAN, BRAD A.

    2011-01-01

    The role of the RhoA/Rho kinase (ROCK) signaling pathway in cell survival remains a very controversial issue, with its activation being pro-apoptotic in many cell types and anti-apoptotic in others. To test if ROCK inhibition contributes to tumor cell survival or death following chemotherapy, we treated cisplatin damaged neuroblastoma cells with a pharmacological ROCK inhibitor (Y27632) or sham, and monitored cell survival, accumulation of a chemoresistant phenotype, and in vivo tumor formation. Additionally, we assayed if ROCK inhibition altered the expression of genes known to be involved in cisplatin resistance. Our studies indicate that ROCK inhibition results in increased cell survival, acquired chemoresistance, and enhanced tumor survival following cisplatin cytotoxicity, due in part to altered expression of cisplatin resistance genes. These findings suggest that ROCK inhibition in combination with cisplatin chemotherapy may lead to enhanced tumor chemoresistance in neuroblastoma. PMID:20878077

  17. Cure Chemistry of Phenylethynyl Terminated Oligomers

    NASA Technical Reports Server (NTRS)

    Wood, Karen H.; Orwoll, Robert A.; Young, Philip R.; Jensen, Brian J.; McNair, Harold M.

    1997-01-01

    The ability to process high performance polymers into quality, void-free composites has been significantly advanced using oligomers terminated with reactive groups which cure or crosslink at elevated temperature without the evolution of volatile byproducts. Several matrix resin systems of considerable interest to the aerospace community utilize phenylethynyl-terminated imide (PETI) technology to achieve this advantage. The present paper addresses the cure chemistry of PETI oligomers. The thermal cure of a low molecular weight model compound was studied using a variety of analytical techniques including differential scanning calorimetry, Fourier transform infrared spectroscopy, and liquid chromatography-mass spectroscopy. The studies indicate an extremely complex cure process. Many stable products were isolated and this paper reports current work on identification of those products. The intent of this research is to provide fundamental insight into the molecular structure of the cured PETI engineering materials so that performance and durability can be more fully assessed.

  18. Oligomer functionalized nanotubes and composites formed therewith

    DOEpatents

    Zettl, Alexander K; Sainsbury, Toby; Frechet, Jean M.J.

    2014-03-18

    Disclosed herein is a sequential functionalization methodology for the covalent modification of nanotubes with between one and four repeat units of a polymer. Covalent attachment of oligomer units to the surface of nanotubes results in oligomer units forming an organic sheath around the nanotubes, polymer-functionalized-nanotubes (P-NTs). P-NTs possess chemical functionality identical to that of the functionalizing polymer, and thus provide nanoscale scaffolds which may be readily dispersed within a monomer solution and participate in the polymerization reaction to form a polymer-nanotube/polymer composite. Formation of polymer in the presence of P-NTs leads to a uniform dispersion of nanotubes within the polymer matrix, in contrast to aggregated masses of nanotubes in the case of pristine-NTs. The covalent attachment of oligomeric units to the surface of nanotubes represents the formation of a functional nanoscale building block which can be readily dispersed and integrated within the polymer to form a novel composite material.

  19. Interaction of arginine oligomer with model membrane

    SciTech Connect

    Yi, Dandan . E-mail: yi_dandan@yahoo.com.cn; Guoming, Li; Gao, Li; Wei, Liang

    2007-08-10

    Short oligomers of arginine (R8) have been shown to cross readily a variety of biological barriers. A hypothesis was put forward that inverted micelles form in biological membranes in the presence of arginine oligomer peptides, facilitating their transfer through the membranes. In order to define the role of peptide-lipid interaction in this mechanism, we prepared liposomes as the model membrane to study the ability of R8 inducing calcein release from liposomes, the fusion of liposomes, R8 binding to liposomes and membrane disturbing activity of the bound R8. The results show that R8 binding to liposome membrane depends on lipid compositions, negative surface charge density and interior water phase pH values of liposomes. R8 has no activity to induce the leakage of calcein from liposomes or improve liposome fusion. R8 does not permeabilize through the membrane spontaneously. These peptides delivering drugs through membranes may depend on receptors and energy.

  20. More than the genes, the tumor microenvironment in neuroblastoma.

    PubMed

    Borriello, Lucia; Seeger, Robert C; Asgharzadeh, Shahab; DeClerck, Yves A

    2016-09-28

    Neuroblastoma is the second most common solid tumor in children. Since the seminal discovery of the role of amplification of the MYCN oncogene in the pathogenesis of neuroblastoma in the 1980s, much focus has been on the contribution of genetic alterations in the progression of this cancer. However it is now clear that not only genetic events play a role but that the tumor microenvironment (TME) substantially contributes to the biology of neuroblastoma. In this article, we present a comprehensive review of the literature on the contribution of the TME to the ten hallmarks of cancer in neuroblastoma and discuss the mechanisms of communication between neuroblastoma cells and the TME that underlie the influence of the TME on neuroblastoma progression. We end our review by discussing how the knowledge acquired over the last two decades in this field is now leading to new clinical trials targeting the TME. PMID:26597947

  1. Ethynyl terminated ester oligomers and polymers therefrom

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); hesives and composite matrices. (Inventor)

    1987-01-01

    A new class of ethynyl-terminated oligomers and the process for preparing same are disclosed. Upon the application of heat, with or without a catalyst, the ethynyl groups react to provide crosslinking and chain extension to increase the polymer use temperature and improve the polymer solvent resistance. These improved polyesters are potentially useful in packaging, magnetic tapes, capacitors, industrial belting, protective coatings, structural adhesives and composite matrices.

  2. Formation of domain-swapped oligomer of cytochrome C from its molten globule state oligomer.

    PubMed

    Deshpande, Megha Subhash; Parui, Partha Pratim; Kamikubo, Hironari; Yamanaka, Masaru; Nagao, Satoshi; Komori, Hirofumi; Kataoka, Mikio; Higuchi, Yoshiki; Hirota, Shun

    2014-07-22

    Many proteins, including cytochrome c (cyt c), have been shown to form domain-swapped oligomers, but the factors governing the oligomerization process remain unrevealed. We obtained oligomers of cyt c by refolding cyt c from its acid molten globule state to neutral pH state under high protein and ion concentrations. The amount of oligomeric cyt c obtained depended on the nature of the anion (chaotropic or kosmotropic) in the solution: ClO4(-) (oligomers, 11% ± 2% (heme unit)), SCN(-) (10% ± 2%), I(-) (6% ± 2%), NO3(-) (3% ± 1%), Br(-) (2% ± 1%), Cl(-) (2% ± 1%), and SO4(2-) (3% ± 1%) for refolding of 2 mM cyt c (anion concentration 125 mM). Dimeric cyt c obtained by refolding from the molten globule state exhibited a domain-swapped structure, in which the C-terminal α-helices were exchanged between protomers. According to small-angle X-ray scattering measurements, approximately 25% of the cyt c molecules were dimerized in the molten globule state containing 125 mM ClO4(-). These results indicate that a certain amount of molten globule state oligomers of cyt c convert to domain-swapped oligomers during refolding and that the intermolecular interactions necessary for domain swapping are present in the molten globule state. PMID:24981551

  3. Kinetics of ligation of fibrin oligomers.

    PubMed

    Nelb, G W; Kamykowski, G W; Ferry, J D

    1980-07-10

    Human fibrinogen was treated with thrombin in the presence of fibrinoligase and calcium ion at pH 8.5, ionic strength 0.45, and the ensuring polymerization was interrupted at various time intervals (t) both before and after the clotting time (tc) by solubilization with a solution of sodium dodecyl sulfate and urea. Aliquots of the solubilized protein were subjected to gel electrophoresis on polyacrylamide gels after disulfide reduction by dithiothreitol and on agarose gels without reduction. The degree of gamma-gamma ligation was determined from the former and the size distribution of ligated oligomers, for degree of polymerization x from 1 to 10, from the latter. The degree of gamma-gamma ligation was calculated independently from the size distribution with the assumption that every junction between two fibrin monomers remaining intact after solubilization is ligated, and this agreed well with the direct determination. The size distribution at t/tc = 1.3 to 1.6 differed somewhat from that calculated by the classical theory of linear polycondensation on the assumption that all reactive sites react with equal probability and rate. Analysis of the difference suggests that ligation of a fibrin digomer is not a random process; the probability of ligation of a given junction between two monomers increases with the oligomer length. The number-average degree of polymerization, xn, of ligated oligomers increases approximately linearly with time up to a value of 1.6. PMID:7391026

  4. Toxicity of methyldopa (Aldomet) to mouse neuroblastoma cells in vivo.

    PubMed

    Chelmicka-Schorr, E; Sportiello, M G; Otten, G R; Arnason, B G

    1983-08-01

    The adrenergic blocking agent methyldopa (Aldomet) is toxic to C-1300 neuroblastoma cells in vivo. Four injections of Aldomet at a dose of 7.5 mg/injection were given over a period of 24 hr to C-1300 neuroblastoma-bearing mice. This treatment killed a significant proportion of the C-1300 neuroblastoma cells. Flow cytometric data suggest that sensitivity of tumor cells to Aldomet is not related to the cell cycle. PMID:6861122

  5. Pharmacological Management of High-risk Neuroblastoma in Children

    PubMed Central

    Ganeshan, Veena R.; Schor, Nina F.

    2015-01-01

    BACKGROUND Neuroblastoma is the most common extracranial solid tumor of childhood. It accounts for 15% of pediatric cancer deaths. Children with high-risk disease have a 3-year event-free survival rate of only 20%. Chemotherapy is the mainstay of the treatment of children with advanced neuroblastoma. OBJECTIVE To review and critically evaluate the pharmacotherapy of neuroblastoma. DATA SOURCES Peer-reviewed and review literature, 2000–2011. STUDY SELECTION All peer-reviewed, published human subjects studies of therapy for neuroblastoma in children were included. Animal model and in vitro studies were included only if they added to the understanding of the mechanism of a proposed or existing human neuroblastoma therapy. DATA SYNTHESIS Current therapeutic options for neuroblastoma involve insufficient differentiation of normal from neoplastic tissue. Critically needed new approaches will increasingly exploit targeting of therapy for unique characteristics of the neuroblastoma cell. CONCLUSIONS Pharmacotherapy for neuroblastoma still suffers from an inadequate therapeutic window. Enhancement of toxicity for tumor and safety for normal tissues will entail innovation in targeting neuroblastoma cells and rescuing or protecting normal tissue elements. PMID:21692548

  6. The genetics of splicing in neuroblastoma

    PubMed Central

    Chen, Justin; Hackett, Christopher S.; Zhang, Shile; Song, Young K.; Bell, Robert J.A.; Molinaro, Annette M.; Quigley, David A.; Balmain, Allan; Song, Jun S.; Costello, Joseph F.; Gustafson, W. Clay; Dyke, Terry Van; Kwok, Pui-Yan; Khan, Javed; Weiss, William A.

    2015-01-01

    Regulation of mRNA splicing, a critical and tightly regulated cellular function, underlies the majority of proteomic diversity, and is frequently disrupted in disease. Using an integrative genomics approach, we combined both genome and exon level transcriptome data in two somatic tissues (cerebella and peripheral ganglia) from a transgenic mouse model of neuroblastoma, a tumor that arises from peripheral neural crest. Here we describe splicing quantitative trait loci (sQTL) associated with differential splicing across the genome that we use to identify genes with previously unknown functions within the splicing pathway and to define de novo intronic splicing motifs that influence splicing from hundreds of bases away. Our results show that these splicing motifs represent sites for functional recurrent mutations and highlight novel candidate genes in human cancers, including childhood neuroblastoma. PMID:25637275

  7. Childhood neuroblastoma masquerading as pheochromocytoma: case report

    PubMed Central

    Moon, Suk-Bae

    2016-01-01

    Neuroblastoma is the most common extracranial solid tumor in children. Mild hypertension is a frequent symptom, presumably an effect of catecholamines that tumors release. Reported herein is the rare occurrence of severe hypertension and subsequent heart failure attributable to adrenal gland neuroblastoma. A 3-year-old boy presented with anterior chest wall protrusion. Physical examination revealed severe hypertension, and left-sided cardiac failure was evident by echocardiography. Catecholamine metabolite (norepinephrine) levels were increased in serum (>2,000 pg/mL) and in urine (1,350.5 µg/day). Abdominal computed tomography scan showed a 7 cm solid mass arising from right adrenal gland. Oral phenoxybenzamine was given for hemodynamic stabilization, and right adrenalectomy was performed to remove an apparent pheochromocytoma. Ultimately, the pathologic diagnosis was ganglioneuroblastoma. Both hypertension and cardiac failure resolved postoperatively. PMID:27051319

  8. Action of HMGB1 on miR-221/222 cluster in neuroblastoma cell lines

    PubMed Central

    Mari, Emanuela; Zicari, Alessandra; Fico, Flavia; Massimi, Isabella; Martina, Lolli; Mardente, Stefania

    2016-01-01

    microRNA (miR/miRNA) are small non-coding RNAs that control gene expression at the post-transcriptional level by targeting mRNAs. Aberrant expression of miRNAs is often observed in different types of cancer. Specific miRNAs function as tumor suppressors or oncogenes and interfere with various aspects of carcinogenesis, including differentiation, proliferation and invasion. Upregulation of miRNAs 221 and 222 has been shown to induce a malignant phenotype in numerous human cancers via inhibition of phosphatase and tensin homolog (PTEN) expression. Neuroblastoma is the most common extracranial solid malignancy in children, which is characterized by cellular heterogeneity that corresponds to different clinical outcomes. The different cellular phenotypes are associated with different gene mutations and miRs that control genetic and epigenetic factors. For this reason miRs are considered a potential therapeutic target in neuroblastoma. The aim of the present study was to investigate the mechanisms by which extracellular high mobility group box 1 (HMGB1) promotes cell growth in neuroblastoma. SK-N-BE(2) and SH-SY5Y neuroblastoma derived cell lines were transfected with the antisense oligonucleotides, anti-miR-221 and −222, followed by treatment with HMGB1 to investigate the expression of the oncosuppressor PTEN. In this study, it was demonstrated that HMGB1, which is released by damaged cells and tumor cells, upregulates miR-221/222 oncogenic clusters in the two human neuroblastoma derived cell lines. The results revealed that the oncogenic cluster miRs 221/222 were more highly expressed by the most undifferentiated cell line [SK-N-BE(2)] compared with the the less tumorigenic cell line (SH-SY5Y) and that exogenous HMGB1 increases this expression. In addition, HMGB1 modulates PTEN expression via miR-221/222, as demonstrated by transiently blocking miR-221/222 with anti-sense oligonucleotides. These results may lead to the development of novel therapeutic strategies for

  9. Structural studies on HCN oligomers. [catalysts for prebiotic processes

    NASA Technical Reports Server (NTRS)

    Ferris, J. P.; Edelson, E. H.; Auyeung, J. M.; Joshi, P. C.

    1981-01-01

    NMR spectral studies on the HCN oligomers suggest the presence of carboxamide and urea groupings. The release of CO2, H2O, HCN, CH3CN, HCONH2 and pyridine on pyrolysis is consistent with the presence of these groupings as well as carboxylic acid groups. No basic primary amine groupings could be detected with fluorescamine. Hydrazinolysis of the HCN oligomers releases 10% of the amino acids normally released by acid hydrolysis. The oligomers give a positive biuret test but this is not due to the presence of peptide bonds. There is no conclusive evidence for the presence of peptide bonds in the HCN oligomers. No diglycine was detected on partial hydrolysis of the HCN oligomers at pH 8.5 suggesting that HCN oligomers were not a source of prebiotic peptides.

  10. Alpha synuclein oligomers oppose long-term potentiation and impair memory through a calcineurin-dependent mechanism: relevance to human synucleopathic diseases

    PubMed Central

    Martin, Zane S.; Neugebauer, Volker; Dineley, Kelly T.; Kayed, Rakez; Zhang, Wenru; Reese, Lindsay C.; Taglialatela, Giulio

    2011-01-01

    Intracellular deposition of fibrillar aggregates of alpha synuclein (αSyn) characterizes neurodegenerative diseases such as Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). However, recent evidence indicates that small αSyn oligomeric aggregates that precede fibril formation may be the most neurotoxic species and can be found extracellularly. This new evidence has changed the view of pathological αSyn aggregation from a self-contained cellular phenomenon to an extracellular event and prompted investigation of the putative effects of extracellular αSyn oligomers. Here, we report that extracellular application of αSyn oligomers detrimentally impacts neuronal welfare and memory function. We found that oligomeric αSyn increased intracellular Ca2+ levels, induced calcineurin (CaN) activity, decreased cAMP response element binding protein (CREB) transcriptional activity and resulted in calcineurin-dependent death of human neuroblastoma cells. Similarily, CaN induction and CREB inhibition were observed when αSyn oligomers were applied to organotypic brain slices, which opposed hippocampal long-term potentiation (LTP). Furthermore, αSyn oligomers induced CaN, inhibited CREB and evoked memory impairments in mice that received acute intracerebroventricular injections. Notably, all these events were reversed by pharmacological inhibition of CaN. Moreover, we found decreased active calcineurin (CaN) and reduced levels of phosphorylated CREB in autopsy brain tissue from patients affected by DLB, which is characterized by deposition of αSyn aggregates and progressive cognitive decline. These results indicate that exogenously-applied αSyn oligomers impact neuronal function and produce memory deficits through mechanisms that involve CaN activation. PMID:22060133

  11. Neuroblastoma with intracranial involvement: an ENSG Study.

    PubMed

    Shaw, P J; Eden, T

    1992-01-01

    We report the experience of the European Neuroblastoma Study Group (ENSG) with central nervous system (CNS) involvement of neuroblastoma. Among this series of intensively treated patients, CNS neuroblastoma was diagnosed by computerised tomography (CT) scanning, rather than by autopsy. Cranial disease occurred in 5% of ENSG patients. Of 11 patients with intracranial disease, 4 had disease in the posterior fossa, a site rarely reported previously. Furthermore, 5 cases had CNS metastases at a time when there was no detectable disease elsewhere, rather than as part of extensive relapse. The pattern of disease we observed, at least for those with parenchymal disease, is in keeping with arterial spread. Although CT scanning is the optimal modality for identifying CNS disease, 2 cases had normal head CT scans prior to the onset of CNS disease. As most patients had symptoms of raised intracranial pressure (RICP) at the time the CNS disease was diagnosed, there does not seem to be any indication for routine CT scanning of the head at diagnosis, but this should be performed as soon as any symptoms or signs appear. With patients living longer with their disease, vigilance must be maintained during follow-up. PMID:1734220

  12. Neuroblastoma and nephroblastoma: a radiological review.

    PubMed

    Dumba, Maureen; Jawad, Noorulhuda; McHugh, Kieran

    2015-01-01

    Neuroblastoma (NBL) is the most common extra-cranial tumour in childhood. It can present as an abdominal mass, but is usually metastatic at diagnosis so the symptomatology can be varied. Nephroblastoma, also more commonly known as a Wilms tumour, is the commonest renal tumour in childhood and more typically presents as abdominal pathology with few constitutional symptoms, although rarely haematuria can be a presenting feature. The pathophysiology and clinical aspects of both tumours including associated risk factors and pathologies are discussed. Oncogenetics and chromosomal abnormalities are increasingly recognised as important prognostic indicators and their impact on initial management is considered. Imaging plays a pivotal role in terms of diagnosis and recent imaging advances mean that radiology has an increasingly crucial role in the management pathway. The use of image defined risk factors in neuroblastoma has begun to dramatically change how this tumour is characterised pre-operatively. The National Wilms Tumour Study Group have comprehensively staged Wilms tumours and this is reviewed as it impacts significantly on management. The use of contrast-enhanced MRI and diffusion-weighted sequences have further served to augment the information available to the clinical team during initial assessment of both neuroblastomas and Wilms tumours. The differences in management strategies are outlined. This paper therefore aims to provide a comprehensive update on these two common paediatric tumours with a particular emphasis on the current crucial role played by imaging. PMID:25889326

  13. Functional-metabolic imaging of neuroblastoma.

    PubMed

    Sharp, S E; Parisi, M T; Gelfand, M J; Yanik, G A; Shulkin, B L

    2013-03-01

    Neuroblastoma is the third most common malignant solid tumor of childhood. It originates from primitive neural crest cells of the sympathetic nervous system. Many imaging procedures help guide therapy and predict outcomes. Anatomic imaging methods, such as CT and MRI, are most useful for evaluation of the primary tumor mass and nearby involved lymph nodes. Functional imaging tracers, such as [123I]MIBG, [18F]FDG, and [99mTc]MDP, are used to assess the extent of disease and to search for distant metastases. [123I]MIBG is the principal functional imaging tracer for the detection and monitoring of neuroblastoma. [18F]FDG PET/CT is an alternative that is valuable in tumors with poor or no MIBG-uptake. [99mTc]MDP bone scans may be useful to assess cortical bone metastases. This article will review the use of [123I]MIBG and other functional imaging agents for the management of patients with neuroblastoma. PMID:23474631

  14. Translational compensation of genomic instability in neuroblastoma

    PubMed Central

    Dassi, Erik; Greco, Valentina; Sidarovich, Viktoryia; Zuccotti, Paola; Arseni, Natalia; Scaruffi, Paola; Paolo Tonini, Gian; Quattrone, Alessandro

    2015-01-01

    Cancer-associated gene expression imbalances are conventionally studied at the genomic, epigenomic and transcriptomic levels. Given the relevance of translational control in determining cell phenotypes, we evaluated the translatome, i.e., the transcriptome engaged in translation, as a descriptor of the effects of genetic instability in cancer. We performed this evaluation in high-risk neuroblastomas, which are characterized by a low frequency of point mutations or known cancer-driving genes and by the presence of several segmental chromosomal aberrations that produce gene-copy imbalances that guide aggressiveness. We thus integrated genome, transcriptome, translatome and miRome profiles in a representative panel of high-risk neuroblastoma cell lines. We identified a number of genes whose genomic imbalance was corrected by compensatory adaptations in translational efficiency. The transcriptomic level of these genes was predictive of poor prognosis in more than half of cases, and the genomic imbalances found in their loci were shared by 27 other tumor types. This homeostatic process is also not limited to copy number-altered genes, as we showed the translational stoichiometric rebalance of histone genes. We suggest that the translational buffering of fluctuations in these dose-sensitive transcripts is a potential driving process of neuroblastoma evolution. PMID:26399178

  15. Translational compensation of genomic instability in neuroblastoma.

    PubMed

    Dassi, Erik; Greco, Valentina; Sidarovich, Viktoryia; Zuccotti, Paola; Arseni, Natalia; Scaruffi, Paola; Tonini, Gian Paolo; Quattrone, Alessandro

    2015-01-01

    Cancer-associated gene expression imbalances are conventionally studied at the genomic, epigenomic and transcriptomic levels. Given the relevance of translational control in determining cell phenotypes, we evaluated the translatome, i.e., the transcriptome engaged in translation, as a descriptor of the effects of genetic instability in cancer. We performed this evaluation in high-risk neuroblastomas, which are characterized by a low frequency of point mutations or known cancer-driving genes and by the presence of several segmental chromosomal aberrations that produce gene-copy imbalances that guide aggressiveness. We thus integrated genome, transcriptome, translatome and miRome profiles in a representative panel of high-risk neuroblastoma cell lines. We identified a number of genes whose genomic imbalance was corrected by compensatory adaptations in translational efficiency. The transcriptomic level of these genes was predictive of poor prognosis in more than half of cases, and the genomic imbalances found in their loci were shared by 27 other tumor types. This homeostatic process is also not limited to copy number-altered genes, as we showed the translational stoichiometric rebalance of histone genes. We suggest that the translational buffering of fluctuations in these dose-sensitive transcripts is a potential driving process of neuroblastoma evolution. PMID:26399178

  16. DNA sequence similarity recognition by hybridization to short oligomers

    DOEpatents

    Milosavljevic, Aleksandar

    1999-01-01

    Methods are disclosed for the comparison of nucleic acid sequences. Data is generated by hybridizing sets of oligomers with target nucleic acids. The data thus generated is manipulated simultaneously with respect to both (i) matching between oligomers and (ii) matching between oligomers and putative reference sequences available in databases. Using data compression methods to manipulate this mutual information, sequences for the target can be constructed.

  17. Polyetherurethane oligomers with aldehyde groups as additives for lubricating oils

    SciTech Connect

    Nikolaev, V.N.; Abramov, E.G.; Tenyushev, A.I.

    1995-01-01

    Polyetherurethane oligomers with aldehyde groups, which we synthesized from polyoxypropylene diols (molecular weight 500, 1000, 1500, 2000, or 3000) with toluene diisocyanate and salicylaldehyde, are of interest as additives for lubricating oils. The effects of these oligomers on the service properties and physicochemical characteristics of lubricating oils were investigated by methods prreviously described. As the lube base stocks we used castor oil, a polyoxypropylene diol and a polyethoxysiloxane. The oligomers are readily soluble in organic solvents and in the lube base stocks, and their solutions are stable during storage and use. We found that the optimal concentration of oligomers is 5%, providing the best lubricating properties, in particular the best antiwear properties.

  18. Small Molecule MRP1 Inhibitor Reversan Increases the Therapeutic Index of Chemotherapy in Mouse Model of Neuroblastoma

    PubMed Central

    Burkhart, Catherine A.; Watt, Fujiko; Murray, Jayne; Pajic, Marina; Prokvolit, Anatoly; Xue, Chengyuan; Flemming, Claudia; Smith, Janice; Purmal, Andrei; Isachenko, Nadezhda; Komarov, Pavel G.; Gurova, Katerina V.; Sartorelli, Alan C.; Marshall, Glenn M.; Norris, Murray D.; Gudkov, Andrei V.; Haber, Michelle

    2009-01-01

    The multidrug resistance-associated protein (MRP1) has been closely linked to poor treatment response in several cancers, most notably neuroblastoma. Homozygous deletion of the MRP1 gene in primary murine neuroblastoma tumors resulted in increased sensitivity to MRP1 substrate drugs (vincristine, etoposide, doxorubicin) compared to tumors containing both copies of wild-type MRP1, indicating that MRP1 plays a significant role in the drug resistance in this tumor type and defining this multidrug transporter as a target for pharmacological suppression. Cell-based readout system was created to functionally determine intracellular accumulation of MRP1 substrates using p53-responsive reporter as an indicator of drug-induced DNA damage. Screening of small molecule libraries in this readout system revealed pyrazolopyrimidines as a prominent structural class of potent MRP1 inhibitors. Reversan, the lead compound of this class, increased the efficacy of both vincristine and etoposide in murine models of neuroblastoma (syngeneic and human xenografts). As opposed to the majority of inhibitors of multidrug transporters, Reversan was not toxic by itself nor did it increase the toxicity of chemotherapeutic drug exposure in mice. Therefore, Reversan represents a new class of non-toxic MRP1 inhibitor, which may be clinically useful for the treatment of neuroblastoma and other MRP1 over-expressing drug refractory tumors by increasing their sensitivity to conventional chemotherapy. PMID:19654298

  19. Functional characterization of a new p53 mutant generated by homozygous deletion in a neuroblastoma cell line

    SciTech Connect

    Nakamura, Yohko; Ozaki, Toshinori; Niizuma, Hidetaka; Ohira, Miki; Kamijo, Takehiko; Nakagawara, Akira . E-mail: akiranak@chiba-cc.jp

    2007-03-23

    p53 is a key modulator of a variety of cellular stresses. In human neuroblastomas, p53 is rarely mutated and aberrantly expressed in cytoplasm. In this study, we have identified a novel p53 mutant lacking its COOH-terminal region in neuroblastoma SK-N-AS cells. p53 accumulated in response to cisplatin (CDDP) and thereby promoting apoptosis in neuroblastoma SH-SY5Y cells bearing wild-type p53, whereas SK-N-AS cells did not undergo apoptosis. We found another p53 (p53{delta}C) lacking a part of oligomerization domain and nuclear localization signals in SK-N-AS cells. p53{delta}C was expressed largely in cytoplasm and lost the transactivation function. Furthermore, a 3'-part of the p53 locus was homozygously deleted in SK-N-AS cells. Thus, our present findings suggest that p53 plays an important role in the DNA-damage response in certain neuroblastoma cells and it seems to be important to search for p53 mutations outside DNA-binding domain.

  20. Anharmonic Vibrational Dynamics of DNA Oligomers

    NASA Astrophysics Data System (ADS)

    Kühn, O.; Došlić, N.; Krishnan, G. M.; Fidder, H.; Heyne, K.

    Combining two-color infared pump-probe spectroscopy and anharmonic force field calculations we characterize the anharmonic coupling patterns between fingerprint modes and the hydrogen-bonded symmetric vNH2 stretching vibration in adenine-thymine dA20-dT20 DNA oligomers. Specifically, it is shown that the anharmonic coupling between the δNH2 bending and the vC4=O4 stretching vibration, both absorbing around 1665 cm-1, can be used to assign the vNH2 fundamental transition at 3215 cm-1 despite the broad background absorption of water.

  1. Mx oligomer: a novel capsid pattern sensor?

    PubMed

    Kong, Jia; Ma, Min; He, Shuangyi; Qin, Xiaohong

    2016-08-01

    Myxovirus resistance proteins represent a family of interferon-induced restriction factors of the innate and adaptive immune system. Human MxB acts as a novel restriction factor with antiviral activity against a range of HIV-1 and other retroviruses mainly by inhibiting the uncoating process after reverse transcription but prior to integration. Based on published data and conservation analysis, we propose a novel hypothesis, in which MxB dimers form higher order oligomers that restrict retroviral replication by binding to the viral capsid. Insights into the mechanistic basis of structural and functional characteristics of MxB will greatly advance our understanding of MxB. PMID:27492442

  2. Adrenal neuroblastoma with metastatic mandibular mass: An unusual presentation.

    PubMed

    Mittal, Deepak; Mandelia, Ankur; Bajpai, Minu; Agarwala, Sandeep

    2015-01-01

    Neuroblastoma very rarely presents as a mandibular mass. We report the case of a 3-year-old female child who presented to us with a right mandibular mass of 3 months duration. She was investigated and diagnosed as a case of stage 4 right adrenal neuroblastoma with mandibular and skull metastasis. PMID:26458598

  3. FAK and p53 Synergistically Decrease Neuroblastoma Cell Survival

    PubMed Central

    Gillory, Lauren A.; Stewart, Jerry E.; Megison, Michael L.; Waters, Alicia M.; Beierle, Elizabeth A.

    2015-01-01

    Neuroblastoma is the most common extracranial solid tumor of childhood and is responsible for over 15% of pediatric cancer deaths. Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that is important in many facets of neuroblastoma tumor development and progression. The p53 oncogene, although wild type in most neuroblastomas, lacks significant function as a tumor suppressor in these tumors. Recent reports have found that FAK and p53 interact in some tumor types. We have hypothesized FAK and p53 coordinately control each other’s expression and also interact in neuroblastoma. In the current study, we showed that not only do FAK and p53 interact but each one controls the expression of the other. In addition, we also examined the effects of FAK inhibition combined with p53 activation in neuroblastoma and showed that these two, in combination, had a synergistic effect upon neuroblastoma cell survival. The findings from this current study help to further our understanding of the regulation of neuroblastoma tumorigenesis, and may provide novel therapeutic strategies and targets for neuroblastoma and other pediatric solid tumors. PMID:25862488

  4. Cell type-dependent ROS and mitophagy response leads to apoptosis or necroptosis in neuroblastoma.

    PubMed

    Radogna, F; Cerella, C; Gaigneaux, A; Christov, C; Dicato, M; Diederich, M

    2016-07-21

    A limiting factor in the therapeutic outcome of children with high-risk neuroblastoma is the intrinsic and acquired resistance to common chemotherapeutic treatments. Here we investigated the molecular mechanisms by which the hemisynthetic cardiac glycoside UNBS1450 overcomes this limitation and induces differential cell death modalities in both neuroblastic and stromal neuroblastoma through stimulation of a cell-type-specific autophagic response eventually leading to apoptosis or necroptosis. In neuroblastic SH-SY5Y cells, we observed a time-dependent production of reactive oxygen species that affects lysosomal integrity inducing lysosome-associated membrane protein 2 degradation and cathepsin B and L activation. Subsequent mitochondrial membrane depolarization and accumulation of mitochondria in phagophores occurred after 8h of UNBS1450 treatment. Results were confirmed by mitochondrial mass analysis, electron microscopy and co-localization of mitochondria with GFP-LC3, suggesting the impaired clearance of damaged mitochondria. Thus, a stress-induced defective autophagic flux and the subsequent lack of clearance of damaged mitochondria sensitized SH-SY5Y cells to UNBS1450-induced apoptosis. Inhibition of autophagy with small inhibitory RNAs against ATG5, ATG7 and Beclin-1 protected SH-SY5Y cells against the cytotoxic effect of UNBS1450 by inhibiting apoptosis. In contrast, autophagy progression towards the catabolic state was observed in stromal SK-N-AS cells: here reactive oxygen species (ROS) generation remained undetectable preserving intact lysosomes and engulfing damaged mitochondria after UNBS1450 treatment. Moreover, autophagy inhibition determined sensitization of SK-N-AS to apoptosis. We identified efficient mitophagy as the key mechanism leading to failure of activation of the apoptotic pathway that increased resistance of SK-N-AS to UNBS1450, triggering rather necroptosis at higher doses. Altogether we characterize here the differential modulation of

  5. Dye-mediated photosensitization of murine neuroblastoma cells

    SciTech Connect

    Sieber, F.; Sieber-Blum, M.

    1986-04-01

    The purpose of this study was to determine if photosensitization mediated by the fluorescent dye, merocyanine 540, could be used to preferentially kill murine neuroblastoma cells in simulated autologous remission marrow grafts. Simultaneous exposure of Neuro 2a or NB41A3 neuroblastoma cells to merocyanine 540 and white light reduced the concentration of in vitro-clonogenic tumor cells 50,000-fold. By contrast, the same treatment had little effect on the graft's ability to rescue lethally irradiated syngeneic hosts. Lethally irradiated C57BL/6J X A/J F1 mice transplanted with photosensitized mixtures of neuroblastoma cells and normal marrow cells (1:100 or 1:10) survived without developing neuroblastomas. It is conceivable that merocyanine 540-mediated photosensitization will prove useful for the extracorporeal purging of residual neuroblastoma cells from human autologous remission marrow grafts.

  6. Liquid Crystal Ordering of Random DNA Oligomers

    NASA Astrophysics Data System (ADS)

    Bellini, Tommaso; Zanchetta, Giuliano; Fraccia, Tommaso; Cerbino, Roberto; Tsai, Ethan; Moran, Mark; Smith, Gregory; Walba, David; Clark, Noel

    2012-02-01

    Concentrated solutions of DNA oligomers (6 to 20 base pairs) organize into chiral nematic (NEM) and columnar (COL) liquid crystal (LC) phases. When the oligomer duplexes are mixed with single strands, LC phase formation proceeds through macroscopic phase separation, as a consequence of the combination of various self-assembly processes including strand pairing, reversible linear aggregation, demixing and LC ordering. We extended our investigation to the case of LC ordering in oligonucleotides whose sequences are partially or entirely randomly chosen, and we observed LC phases even in entirely random 20mers, corresponding to a family of 4^20 10^12 different sequences. We have tracked the origin of this behaviour: random sequences pair into generally defected duplexes, a large fraction of them terminating with stretches of unpaired bases (overhangs); overhangs promote linear aggregation of duplexes, with a mean strength depending on the overhang length; LC formation is accompanied by a phase separation where the duplexes with longer overhangs aggregate to form COL LC domains that coexist with an isotropic fluid rich in duplexes whose structure cannot aggregate.

  7. Cooperative Switching in Nanofibers of Azobenzene Oligomers

    NASA Astrophysics Data System (ADS)

    Weber, Christopher; Liebig, Tobias; Gensler, Manuel; Zykov, Anton; Pithan, Linus; Rabe, Jürgen P.; Hecht, Stefan; Bléger, David; Kowarik, Stefan

    2016-05-01

    Next-generation molecular devices and machines demand the integration of molecular switches into hierarchical assemblies to amplify the response of the system from the molecular level to the meso- or macro-scale. Here, we demonstrate that multi-azobenzene oligomers can assemble to form robust supramolecular nanofibers in which they can be switched repeatedly between the E- and Z-configuration. While in isolated oligomers the azobenzene units undergo reversible photoisomerization independently, in the nanofibers they are coupled via intermolecular interactions and switch cooperatively as evidenced by unusual thermal and kinetic behavior. We find that the photoisomerization rate from the Z-isomer to the E-isomer depends on the fraction of Z-azobenzene in the nanofibers, and is increased by more than a factor of 4 in Z-rich fibers when compared to E-rich fibers. This demonstrates the great potential of coupling individual photochromic units for increasing their quantum efficiency in the solid state with potential relevance for actuation and sensing.

  8. SAXS fingerprints of aldehyde dehydrogenase oligomers.

    PubMed

    Tanner, John J

    2015-12-01

    Enzymes of the aldehyde dehydrogenase (ALDH) superfamily catalyze the nicotinamide adenine dinucleotide-dependent oxidation of aldehydes to carboxylic acids. ALDHs are important in detoxification of aldehydes, amino acid metabolism, embryogenesis and development, neurotransmission, oxidative stress, and cancer. Mutations in genes encoding ALDHs cause metabolic disorders, including alcohol flush reaction (ALDH2), Sjögren-Larsson syndrome (ALDH3A2), hyperprolinemia type II (ALDH4A1), γ-hydroxybutyric aciduria (ALDH5A1), methylmalonic aciduria (ALDH6A1), pyridoxine dependent epilepsy (ALDH7A1), and hyperammonemia (ALDH18A1). We previously reported crystal structures and small-angle X-ray scattering (SAXS) analyses of ALDHs exhibiting dimeric, tetrameric, and hexameric oligomeric states (Luo et al., Biochemistry 54 (2015) 5513-5522; Luo et al., J. Mol. Biol. 425 (2013) 3106-3120). Herein I provide the SAXS curves, radii of gyration, and distance distribution functions for the three types of ALDH oligomer. The SAXS curves and associated analysis provide diagnostic fingerprints that allow rapid identification of the type of ALDH oligomer that is present in solution. The data sets provided here serve as a benchmark for characterizing oligomerization of ALDHs. PMID:26693506

  9. Solvent induced track sensitization. Extraction of oligomers

    NASA Astrophysics Data System (ADS)

    Apel, P.; Angert, N.; Brüchle, W.; Hermann, H.; Kampschulte, U.; Klein, P.; Kravets, L. I.; Oganessian, Yu. Ts.; Remmert, G.; Spohr, R.; Steckenreiter, T.; Trautmann, C.; Vetter, J.

    1994-04-01

    Oligomer extraction from polyethylene terephthalate (PET) irradiated by xenon ions of 11.4 MeV/u is investigated using UV spectrophotometry and gel permeation chromatography (GPC). The cyclic trimer is identified as the predominant diffusing species removed during extraction by dimethyl formamide (DMF). Extraction dynamics is modeled by a rapid (time constant ≈ 2 min) and a slow (time constant ≈ 100 min) diffusion process attributed to the latent ion tracks and to the virgin material, respectively. Thereby latent tracks act simultaneously as irrigation and drainage pipes for the transfer of the solvent into and the extraction of oligomers from the polymer matrix. Thus tracks help to release osmotic pressure differences and to avoid blistering of the unirradiated polymer during solvent exchange. The total extracted mass per track shows a characteristic decrease with increasing ion fluence interpreted as oxygen effect, due to the decreasing supply of oxygen in the sample during irradiation. The extractable mass corresponds to an equivalent track diameter of initially around 10 nm contracting with increasing ion fluence to an asymptotic value around 3 nm.

  10. Cooperative Switching in Nanofibers of Azobenzene Oligomers.

    PubMed

    Weber, Christopher; Liebig, Tobias; Gensler, Manuel; Zykov, Anton; Pithan, Linus; Rabe, Jürgen P; Hecht, Stefan; Bléger, David; Kowarik, Stefan

    2016-01-01

    Next-generation molecular devices and machines demand the integration of molecular switches into hierarchical assemblies to amplify the response of the system from the molecular level to the meso- or macro-scale. Here, we demonstrate that multi-azobenzene oligomers can assemble to form robust supramolecular nanofibers in which they can be switched repeatedly between the E- and Z-configuration. While in isolated oligomers the azobenzene units undergo reversible photoisomerization independently, in the nanofibers they are coupled via intermolecular interactions and switch cooperatively as evidenced by unusual thermal and kinetic behavior. We find that the photoisomerization rate from the Z-isomer to the E-isomer depends on the fraction of Z-azobenzene in the nanofibers, and is increased by more than a factor of 4 in Z-rich fibers when compared to E-rich fibers. This demonstrates the great potential of coupling individual photochromic units for increasing their quantum efficiency in the solid state with potential relevance for actuation and sensing. PMID:27161608

  11. Cooperative Switching in Nanofibers of Azobenzene Oligomers

    PubMed Central

    Weber, Christopher; Liebig, Tobias; Gensler, Manuel; Zykov, Anton; Pithan, Linus; Rabe, Jürgen P.; Hecht, Stefan; Bléger, David; Kowarik, Stefan

    2016-01-01

    Next-generation molecular devices and machines demand the integration of molecular switches into hierarchical assemblies to amplify the response of the system from the molecular level to the meso- or macro-scale. Here, we demonstrate that multi-azobenzene oligomers can assemble to form robust supramolecular nanofibers in which they can be switched repeatedly between the E- and Z-configuration. While in isolated oligomers the azobenzene units undergo reversible photoisomerization independently, in the nanofibers they are coupled via intermolecular interactions and switch cooperatively as evidenced by unusual thermal and kinetic behavior. We find that the photoisomerization rate from the Z-isomer to the E-isomer depends on the fraction of Z-azobenzene in the nanofibers, and is increased by more than a factor of 4 in Z-rich fibers when compared to E-rich fibers. This demonstrates the great potential of coupling individual photochromic units for increasing their quantum efficiency in the solid state with potential relevance for actuation and sensing. PMID:27161608

  12. In vivo demonstration that α-synuclein oligomers are toxic

    PubMed Central

    Winner, Beate; Jappelli, Roberto; Maji, Samir K.; Desplats, Paula A.; Boyer, Leah; Aigner, Stefan; Hetzer, Claudia; Loher, Thomas; Vilar, Marçal; Campioni, Silvia; Tzitzilonis, Christos; Soragni, Alice; Jessberger, Sebastian; Mira, Helena; Consiglio, Antonella; Pham, Emiley; Masliah, Eliezer; Gage, Fred H.; Riek, Roland

    2011-01-01

    The aggregation of proteins into oligomers and amyloid fibrils is characteristic of several neurodegenerative diseases, including Parkinson disease (PD). In PD, the process of aggregation of α-synuclein (α-syn) from monomers, via oligomeric intermediates, into amyloid fibrils is considered the disease-causative toxic mechanism. We developed α-syn mutants that promote oligomer or fibril formation and tested the toxicity of these mutants by using a rat lentivirus system to investigate loss of dopaminergic neurons in the substantia nigra. The most severe dopaminergic loss in the substantia nigra is observed in animals with the α-syn variants that form oligomers (i.e., E57K and E35K), whereas the α-syn variants that form fibrils very quickly are less toxic. We show that α-syn oligomers are toxic in vivo and that α-syn oligomers might interact with and potentially disrupt membranes. PMID:21325059

  13. Atomic View of a Toxic Amyloid Small Oligomer

    PubMed Central

    Laganowsky, Arthur; Liu, Cong; Sawaya, Michael R.; Whitelegge, Julian P.; Park, Jiyong; Zhao, Minglei; Pensalfini, Anna; Soriaga, Angela; Landau, Meytal; Teng, Poh K.; Cascio, Duilio; Glabe, Charles; Eisenberg, David

    2014-01-01

    Amyloid diseases, including Alzheimer's, Parkinson's, and the prion conditions, are each associated with a particular protein in fibrillar form. These amyloid fibrils were long suspected to be the disease agents, but evidence suggests that smaller, often transient and polymorphic oligomers are the toxic entities. Here we identify a segment of the amyloid-forming protein, alphaB crystallin, which forms an oligomeric complex exhibiting properties of other amyloid oligomers: beta-sheet-rich structure, cytotoxicity, and recognition by an anti-oligomer antibody. The X-ray-derived atomic structure of the oligomer reveals a cylindrical barrel, formed from six anti-parallel, protein strands, which we term a cylindrin. The cylindrin structure is compatible with a sequence segment from the Abeta protein of Alzheimer's disease. Cylindrins offer models for the hitherto elusive structures of amyloid oligomers. PMID:22403391

  14. Atomic View of a Toxic Amyloid Small Oligomer

    SciTech Connect

    Laganowsky, Arthur; Liu, Cong; Sawaya, Michael R.; Whitelegge, Julian P.; Park, Jiyong; Zhao, Minglei; Pensalfini, Anna; Soriaga, Angela B.; Landau, Meytal; Teng, Poh K.; Cascio, Duilio; Glabe, Charles; Eisenberg, David

    2012-04-30

    Amyloid diseases, including Alzheimer's, Parkinson's, and the prion conditions, are each associated with a particular protein in fibrillar form. These amyloid fibrils were long suspected to be the disease agents, but evidence suggests that smaller, often transient and polymorphic oligomers are the toxic entities. Here, we identify a segment of the amyloid-forming protein {alpha}{beta} crystallin, which forms an oligomeric complex exhibiting properties of other amyloid oligomers: {beta}-sheet-rich structure, cytotoxicity, and recognition by an oligomer-specific antibody. The x-ray-derived atomic structure of the oligomer reveals a cylindrical barrel, formed from six antiparallel protein strands, that we term a cylindrin. The cylindrin structure is compatible with a sequence segment from the {beta}-amyloid protein of Alzheimer's disease. Cylindrins offer models for the hitherto elusive structures of amyloid oligomers.

  15. Vibronic line shapes of PTCDA oligomers in helium nanodroplets.

    PubMed

    Roden, Jan; Eisfeld, Alexander; Dvořák, Matthieu; Bünermann, Oliver; Stienkemeier, Frank

    2011-02-01

    Oligomers of the organic semiconductor 3,4,9,10-perylene-tetracarboxylic-dianhydride, C(24)H(8)O(6) (PTCDA) are studied by means of helium nanodroplet isolation spectroscopy. In contrast to the monomer absorption spectrum, which exhibits clearly separated, very sharp absorption lines, it is found that the oligomer spectrum consists of three main peaks having an apparent width orders of magnitude larger than the width of the monomer lines. Using a simple theoretical model for the oligomer, in which a Frenkel exciton couples to internal vibrational modes of the monomers, these experimental findings are nicely reproduced. The three peaks present in the oligomer spectrum can already be obtained taking only one effective vibrational mode of the PTCDA molecule into account. The inclusion of more vibrational modes leads to quasicontinuous spectra, resembling the broad oligomer spectra. PMID:21303160

  16. Alpha-Synuclein Oligomers Interact with Metal Ions to Induce Oxidative Stress and Neuronal Death in Parkinson's Disease

    PubMed Central

    Deas, Emma; Cremades, Nunilo; Angelova, Plamena R.; Ludtmann, Marthe H.R.; Yao, Zhi; Chen, Serene; Horrocks, Mathew H.; Banushi, Blerida; Little, Daniel; Devine, Michael J.; Gissen, Paul; Klenerman, David; Dobson, Christopher M.; Wood, Nicholas W.

    2016-01-01

    Abstract Aims: Protein aggregation and oxidative stress are both key pathogenic processes in Parkinson's disease, although the mechanism by which misfolded proteins induce oxidative stress and neuronal death remains unknown. In this study, we describe how aggregation of alpha-synuclein (α-S) from its monomeric form to its soluble oligomeric state results in aberrant free radical production and neuronal toxicity. Results: We first demonstrate excessive free radical production in a human induced pluripotent stem-derived α-S triplication model at basal levels and on application of picomolar doses of β-sheet-rich α-S oligomers. We probed the effects of different structural species of α-S in wild-type rat neuronal cultures and show that both oligomeric and fibrillar forms of α-S are capable of generating free radical production, but that only the oligomeric form results in reduction of endogenous glutathione and subsequent neuronal toxicity. We dissected the mechanism of oligomer-induced free radical production and found that it was interestingly independent of several known cellular enzymatic sources. Innovation: The oligomer-induced reactive oxygen species (ROS) production was entirely dependent on the presence of free metal ions as addition of metal chelators was able to block oligomer-induced ROS production and prevent oligomer-induced neuronal death. Conclusion: Our findings further support the causative role of soluble amyloid oligomers in triggering neurodegeneration and shed light into the mechanisms by which these species cause neuronal damage, which, we show here, can be amenable to modulation through the use of metal chelation. Antioxid. Redox Signal. 24, 376–391. PMID:26564470

  17. Role of the Fast Kinetics of Pyroglutamate-Modified Amyloid-β Oligomers in Membrane Binding and Membrane Permeability

    PubMed Central

    2015-01-01

    Membrane permeability to ions and small molecules is believed to be a critical step in the pathology of Alzheimer’s disease (AD). Interactions of oligomers formed by amyloid-β (Aβ) peptides with the plasma cell membrane are believed to play a fundamental role in the processes leading to membrane permeability. Among the family of Aβs, pyroglutamate (pE)-modified Aβ peptides constitute the most abundant oligomeric species in the brains of AD patients. Although membrane permeability mechanisms have been studied for full-length Aβ1–40/42 peptides, these have not been sufficiently characterized for the more abundant AβpE3–42 fragment. Here we have compared the adsorbed and membrane-inserted oligomeric species of AβpE3–42 and Aβ1–42 peptides. We find lower concentrations and larger dimensions for both species of membrane-associated AβpE3–42 oligomers. The larger dimensions are attributed to the faster self-assembly kinetics of AβpE3–42, and the lower concentrations are attributed to weaker interactions with zwitterionic lipid headgroups. While adsorbed oligomers produced little or no significant membrane structural damage, increased membrane permeabilization to ionic species is understood in terms of enlarged membrane-inserted oligomers. Membrane-inserted AβpE3–42 oligomers were also found to modify the mechanical properties of the membrane. Taken together, our results suggest that membrane-inserted oligomers are the primary species responsible for membrane permeability. PMID:24950761

  18. Spinal deformity in children treated for neuroblastoma

    SciTech Connect

    Mayfield, J.K.; Riseborough, E.J.; Jaffe, N.; Nehme, M.E.

    1981-02-01

    Of seventy-four children who were treated at a mean age of seventeen months for neuroblastoma and survived more than five years, fifty-six had spinal deformity due either to the disease or to the treatment after a mean follow-up of 12.9 years. Of these fifty-six, 50 per cent had post-radiation scoliosis, and 16 per cent had post-radiation kyphosis, most frequently at the thoracolumbar junction, at the time of follow-up. Two kyphotic thoracolumbar curve patterns were identified: an angular kyphosis with a short radius of curvature and its apex at the twelfth thoracic and first lumbar vertebrae, and a thoracic kyphosis with a long radius of curvature that extended into the lumbar spine. The post-radiation deformity - both the scoliosis and the kyphosis - progressed with growth, the scoliosis at a rate of 1 degree per year and the kyphosis at a rate of 3 degrees per year. Epidural spread of the neuroblastoma was associated with most of the cases of severe scoliosis and kyphosis. The deformity was due either to the laminectomy or to the paraplegia acting in conjunction with the radiation. Eighteen per cent of 419 children with this malignant disease survived more than five years, and of the survivors, 20 per cent had spinal deformity severe enough to warrant treatment. The factors associated with the development of spinal deformity in patient treated for neuroblastoma were: orthovoltage radiation exceeding 3000 rads, asymmetrical radiation of the spine, thoracolumbar kyphosis, and epidural spread of the tumor.

  19. Accumulation of oligomer-prone α-synuclein exacerbates synaptic and neuronal degeneration in vivo

    PubMed Central

    Rockenstein, Edward; Nuber, Silke; Overk, Cassia R.; Ubhi, Kiren; Mante, Michael; Patrick, Christina; Adame, Anthony; Trejo-Morales, Margarita; Gerez, Juan; Picotti, Paola; Jensen, Poul H.; Campioni, Silvia; Riek, Roland; Winkler, Jürgen; Gage, Fred H.; Winner, Beate

    2014-01-01

    In Parkinson’s disease and dementia with Lewy bodies, α-synuclein aggregates to form oligomers and fibrils; however, the precise nature of the toxic α-synuclein species remains unclear. A number of synthetic α-synuclein mutations were recently created (E57K and E35K) that produce species of α-synuclein that preferentially form oligomers and increase α-synuclein-mediated toxicity. We have shown that acute lentiviral expression of α-synuclein E57K leads to the degeneration of dopaminergic neurons; however, the effects of chronic expression of oligomer-prone α-synuclein in synapses throughout the brain have not been investigated. Such a study could provide insight into the possible mechanism(s) through which accumulation of α-synuclein oligomers in the synapse leads to neurodegeneration. For this purpose, we compared the patterns of neurodegeneration and synaptic damage between a newly generated mThy-1 α-synuclein E57K transgenic mouse model that is prone to forming oligomers and the mThy-1 α-synuclein wild-type mouse model (Line 61), which accumulates various forms of α-synuclein. Three lines of α-synuclein E57K (Lines 9, 16 and 54) were generated and compared with the wild-type. The α-synuclein E57K Lines 9 and 16 were higher expressings of α-synuclein, similar to α-synuclein wild-type Line 61, and Line 54 was a low expressing of α-synuclein compared to Line 61. By immunoblot analysis, the higher-expressing α-synuclein E57K transgenic mice showed abundant oligomeric, but not fibrillar, α-synuclein whereas lower-expressing mice accumulated monomeric α-synuclein. Monomers, oligomers, and fibrils were present in α-synuclein wild-type Line 61. Immunohistochemical and ultrastructural analyses demonstrated that α-synuclein accumulated in the synapses but not in the neuronal cells bodies, which was different from the α-synuclein wild-type Line 61, which accumulates α-synuclein in the soma. Compared to non-transgenic and lower-expressing mice, the

  20. Accumulation of oligomer-prone α-synuclein exacerbates synaptic and neuronal degeneration in vivo.

    PubMed

    Rockenstein, Edward; Nuber, Silke; Overk, Cassia R; Ubhi, Kiren; Mante, Michael; Patrick, Christina; Adame, Anthony; Trejo-Morales, Margarita; Gerez, Juan; Picotti, Paola; Jensen, Poul H; Campioni, Silvia; Riek, Roland; Winkler, Jürgen; Gage, Fred H; Winner, Beate; Masliah, Eliezer

    2014-05-01

    In Parkinson's disease and dementia with Lewy bodies, α-synuclein aggregates to form oligomers and fibrils; however, the precise nature of the toxic α-synuclein species remains unclear. A number of synthetic α-synuclein mutations were recently created (E57K and E35K) that produce species of α-synuclein that preferentially form oligomers and increase α-synuclein-mediated toxicity. We have shown that acute lentiviral expression of α-synuclein E57K leads to the degeneration of dopaminergic neurons; however, the effects of chronic expression of oligomer-prone α-synuclein in synapses throughout the brain have not been investigated. Such a study could provide insight into the possible mechanism(s) through which accumulation of α-synuclein oligomers in the synapse leads to neurodegeneration. For this purpose, we compared the patterns of neurodegeneration and synaptic damage between a newly generated mThy-1 α-synuclein E57K transgenic mouse model that is prone to forming oligomers and the mThy-1 α-synuclein wild-type mouse model (Line 61), which accumulates various forms of α-synuclein. Three lines of α-synuclein E57K (Lines 9, 16 and 54) were generated and compared with the wild-type. The α-synuclein E57K Lines 9 and 16 were higher expressings of α-synuclein, similar to α-synuclein wild-type Line 61, and Line 54 was a low expressing of α-synuclein compared to Line 61. By immunoblot analysis, the higher-expressing α-synuclein E57K transgenic mice showed abundant oligomeric, but not fibrillar, α-synuclein whereas lower-expressing mice accumulated monomeric α-synuclein. Monomers, oligomers, and fibrils were present in α-synuclein wild-type Line 61. Immunohistochemical and ultrastructural analyses demonstrated that α-synuclein accumulated in the synapses but not in the neuronal cells bodies, which was different from the α-synuclein wild-type Line 61, which accumulates α-synuclein in the soma. Compared to non-transgenic and lower-expressing mice, the

  1. Deciphering aggregates, prefibrillar oligomers and protofibrils of cytochrome c.

    PubMed

    Amani, Samreen; Naeem, Aabgeena

    2014-08-01

    Aggregation of protein into insoluble intracellular complexes and inclusion bodies underlies the pathogenesis of human neurodegenerative diseases. Importance of cytochrome c (cyt c) arises from its involvement in apoptosis, sequence homology and for studying molecular evolution. A systemic investigation of polyethylene glycol (PEG) and trifluoroethanol (TFE) on the conformational stability of cyt c as a model hemeprotein was made using multi-methodological approach. Cyt c exists as molten globule (MG) at 60% PEG-400 and 40% TFE as confirmed by far-UV CD, attenuated total reflection Fourier transform infrared spectroscopy, Trp environment, 8-anilino-1-naphthalene-sulfonic acid (ANS) binding and blue shift in the soret band. Q-band splitting in MG states specifies conformational changes in the hydrophobic heme-binding pocket. Aggregates were detected at 90% PEG-400 and 50% TFE as confirmed by increase thioflavin T and ANS fluorescence and shift in Congo red absorbance. Detection of prefibrils and protofibrils at 90% PEG-400 and 50% TFE was possible after 72-h incubation. Single cell gel electrophoresis of prefibrils and protofibrils showed DNA damage confirming their toxicity and potential health hazards. Scanning electron microscopy and XRD analysis confirmed prefibrillar oligomers and protofibrils of cyt c. PMID:24729012

  2. Familial neuroblastoma. Case reports, literature review, and etiologic considerations.

    PubMed

    Kushner, B H; Gilbert, F; Helson, L

    1986-05-01

    The phenomenon of familial neuroblastoma is discussed in the context of case reports describing disseminated neuroblastoma in two of three half-brothers who share a common unaffected mother and who each have a different father. This family's cytogenetics proved to be unremarkable; also, the mother's peripheral blood DNA did not show tumorigenic capacities in transfection-nude mice experiments. An analysis of reported cases permits an updated examination of the clinical features of this entity and defines the limits of genetic counseling of families of all neuroblastoma patients. Multiple primaries are a hallmark of familial neuroblastoma. Most diagnoses are made in the first 18 months of life and at ages that fall within 12 months of the age of diagnosis of the other affected family member. Difficulties in determining the incidence and penetrance of an inherited susceptibility to neuroblastoma derive from undiagnosed tumors that have undergone regression or spontaneous maturation to benign ganglioneuroma, as well as from early deaths or long-term treatment complications that preclude reproduction and multigenerational pedigrees. Nevertheless, the risk of neuroblastoma in siblings or offspring of the large majority of persons with neuroblastoma appears to be less than 6%. Recent observations concerning chromosomal aberrations and oncogenes in embryonal malignancies are presented in an integrated model of tumorigenesis that corresponds to clinical experience. PMID:3955526

  3. Enzymatic hydrolysis of PTT polymers and oligomers.

    PubMed

    Eberl, A; Heumann, S; Kotek, R; Kaufmann, F; Mitsche, S; Cavaco-Paulo, A; Gübitz, G M

    2008-05-20

    Oligomers and polymers (film, fabrics) of the linear aromatic polyester poly(trimethylene terephthalate) (PTT) were treated with polyesterases from Thermomyces lanuginosus, Penicillium citrinum, Thermobifida fusca and Fusarium solani pisi. The cutinase from T. fusca was found to release the highest amounts of hydrolysis products from PTT materials and was able to open and hydrolyse a cyclic PTT dimer according to RP-HPLC-UV detection. In contrast, the lipase from T. lanuginosus also showed activity on the PTT fibres and on bis(3-hydroxypropyl) terephthalate (BHPT) but was not able to hydrolyse the polymer film, mono(3-hydroxypropyl) terephthalate (MHPT) nor the cyclic dimer of PTT. As control enzymes inhibited with mercury chloride were used. Surface hydrophilicity changes were investigated with contact angle measurements and the degree of crystallinity changes were determined with DSC. PMID:18405994

  4. Rectification mechanism in diblock oligomer molecular diodes.

    PubMed

    Oleynik, I I; Kozhushner, M A; Posvyanskii, V S; Yu, L

    2006-03-10

    We investigated a mechanism of rectification in diblock oligomer diode molecules that have recently been synthesized and showed a pronounced asymmetry in the measured I-V spectrum. The observed rectification effect is due to the resonant nature of electron transfer in the system and the localization properties of bound state wave functions of resonant states of the tunneling electron interacting with an asymmetric molecule in an electric field. The asymmetry of the tunneling wave function is enhanced or weakened depending on the polarity of the applied bias. The conceptually new theoretical approach, the Green's function theory of sub-barrier scattering, is able to provide a physically transparent explanation of this rectification effect based on the concept of the bound state spectrum of a tunneling electron. The theory predicts the characteristic features of the I-V spectrum in qualitative agreement with experiment. PMID:16606295

  5. First-principles simulations of thiophene oligomers

    NASA Astrophysics Data System (ADS)

    Scherlis, Damian; Marzari, Nicola

    2003-03-01

    Conducting polymers, extensively investigated for their use in electronic and nanotechnology applications, have recently gained prominence for their possible use as molecular actuators in mechanical and bioengineering devices. We have focused our efforts on thiophene-based compounds, a class of materials that can be designed for high stress generation and large linear displacement (actuation strain), ideally outperforming mammalian muscle. Key features for the development of these materials are the microscopic binding properties of thiophene and thiophene oligomers stacks, where applied electric fields lead to oxidation and enhanced pi-pi bonding. We have completed the structural studies of neutral and charged oligothiophene dimers, in the search for efficient dimerization mechanisms. A comparison between different density-functional and quantum-chemistry approaches is critically presented, as are solvation effects, described in this work with a combination of first-principles molecular dynamics and a QM/MM approach for the solvating medium.

  6. Predicting outcomes for children with neuroblastoma.

    PubMed

    Vermeulen, Joëlle; De Preter, Katleen; Mestdagh, Pieter; Laureys, Geneviève; Speleman, Frank; Vandesompele, Jo

    2010-07-01

    One of the main challenges in clinical cancer research remains to be accurate outcome prediction at the time of diagnosis. Although not frequent in absolute terms, neuroblastoma represents an important clinical challenge, as it is fatal in almost half of the patients despite advances in multimodal anti-cancer therapies. Four major risk stratification systems for neuroblastoma patients are currently being used in various parts of the world. Systems are based on a combination of various clinical, histopathological, and biological factors. Accordingly, different therapeutic schemes exist ranging from wait-and-see approaches to intensive multimodal therapies. Clinical experience with the currently used risk stratification systems suggests that the stratification of patients for treatment is useful, but patients with the same clinico-pathological parameters, receiving the same treatment, can have markedly different clinical courses. Therefore, the challenge remains to identify additional tumor-specific and sensitive prognostic markers for improved risk estimation at the time of diagnosis and to improve the choice of risk-related therapy. Various studies have put forward new prognostic markers, including copy number aberrations, gene expression signatures, and epigenetic markers. PMID:20670596

  7. Effect of Oligomer Length on Photophysical Properties of Platinum Acetylide Donor-Acceptor-Donor Oligomers.

    PubMed

    Cekli, Seda; Winkel, Russell W; Schanze, Kirk S

    2016-07-21

    We report a systematic study that explores how the triplet excited state is influenced by conjugation length in a series of benzothiadiazole units containing donor-acceptor-donor (DAD)-type platinum acetylide oligomers and polymer. The singlet and triplet excited states for the series were characterized by an array of photophysical methods including steady-state luminescence spectroscopy and femtosecond-nanosecond transient absorption spectroscopy. In addition to the experimental work, a computational study using density functional theory was conducted to gain more information about the structure, composition, and energies of the frontier molecular orbitals. It is observed that both the singlet and triplet excited states are mainly localized on a single donor-acceptor-donor unit in the oligomers. Interestingly, it is discovered that the intersystem crossing efficiency increases dramatically in the longer oligomers. The effect is attributed to an enhanced contribution of the heavy metal platinum in the frontier orbitals (HOMO and LUMO), an effect that leads to enhanced spin-orbit coupling. PMID:27291712

  8. Neuroblastoma in an adult: case presentation and literature review.

    PubMed

    Smith, Laura; Minter, Steve; O'Brien, Paul; Kraveka, Jacqueline M; Medina, Ana Maria; Lazarchick, John

    2013-01-01

    Neuroblastoma is the most common malignancy in children less than one year of age, but is rare in adults. Adult neuroblastoma differs from pediatric cases by lacking classical features including low incidence of MYCN amplification, elevated urinary catecholamimes, and MIBG avidity. The diagnosis may not be initially considered because of the rarity, which emphasizes the importance of immunohistochemical staining and cytogenetic testing in aiding the diagnosis. We present a case of neuroblastoma in a 39-year-old woman who failed to respond to intensive therapy for this malignancy and died within a year after diagnosis. PMID:23462610

  9. Primary sellar neuroblastoma. A new case and review of literature.

    PubMed

    Dupuy, Martin; Bonneville, Fabrice; Grunenwald, Solange; Breibach, Florence; Delisle, Marie-Bernadette; Chaynes, Patrick; Sol, Jean-Christophe; Caron, Philippe

    2012-06-01

    The primary intracranial development of olfactory neuroblastomas, outside olfactory epithelium, is rare. We report a case of primary sellar neuroblastoma without any aggressive histopathological features, managed solely surgically without adjuvant therapy, with good outcomes at 3 years. Primary sellar neuroblastomas mostly occur in women in the 4th decade with a context of a non-secreting pituitary tumour. Diagnosis is made on histopathological examination (small cells, fibrillary intercellular background, strong immunoreactivity for neurons markers, negative immunoreactivity for anterior pituitary hormones). Management is based on surgery. Adjuvant treatment is not consensual, largely depends on patient's conditions and aggressive histopathological features. PMID:22497798

  10. Antiparallel Triple-strand Architecture for Prefibrillar Aβ42 Oligomers*

    PubMed Central

    Gu, Lei; Liu, Cong; Stroud, James C.; Ngo, Sam; Jiang, Lin; Guo, Zhefeng

    2014-01-01

    Aβ42 oligomers play key roles in the pathogenesis of Alzheimer disease, but their structures remain elusive partly due to their transient nature. Here, we show that Aβ42 in a fusion construct can be trapped in a stable oligomer state, which recapitulates characteristics of prefibrillar Aβ42 oligomers and enables us to establish their detailed structures. Site-directed spin labeling and electron paramagnetic resonance studies provide structural restraints in terms of side chain mobility and intermolecular distances at all 42 residue positions. Using these restraints and other biophysical data, we present a novel atomic-level oligomer model. In our model, each Aβ42 protein forms a single β-sheet with three β-strands in an antiparallel arrangement. Each β-sheet consists of four Aβ42 molecules in a head-to-tail arrangement. Four β-sheets are packed together in a face-to-back fashion. The stacking of identical segments between different β-sheets within an oligomer suggests that prefibrillar oligomers may interconvert with fibrils via strand rotation, wherein β-strands undergo an ∼90° rotation along the strand direction. This work provides insights into rational design of therapeutics targeting the process of interconversion between toxic oligomers and non-toxic fibrils. PMID:25118290

  11. Elucidating molecular mass and shape of a neurotoxic Aβ oligomer.

    PubMed

    Sebollela, Adriano; Mustata, Gina-Mirela; Luo, Kevin; Velasco, Pauline T; Viola, Kirsten L; Cline, Erika N; Shekhawat, Gajendra S; Wilcox, Kyle C; Dravid, Vinayak P; Klein, William L

    2014-12-17

    Alzheimer's disease (AD), the most prevalent type of dementia, has been associated with the accumulation of amyloid β oligomers (AβOs) in the central nervous system. AβOs vary widely in size, ranging from dimers to larger than 100 kDa. Evidence indicates that not all oligomers are toxic, and there is yet no consensus on the size of the actual toxic oligomer. Here we used NU4, a conformation-dependent anti-AβO monoclonal antibody, to investigate size and shape of a toxic AβO assembly. By using size-exclusion chromatography and immuno-based detection, we isolated an AβO-NU4 complex amenable for biochemical and morphological studies. The apparent molecular mass of the NU4-targeted oligomer was 80 kDa. Atomic force microscopy imaging of the AβO-NU4 complex showed a size distribution centered at 5.37 nm, an increment of 1.5 nm compared to the size of AβOs (3.85 nm). This increment was compatible with the size of NU4 (1.3 nm), suggesting a 1:1 oligomer to NU4 ratio. NU4-reactive oligomers extracted from AD human brain concentrated in a molecular mass range similar to that found for in vitro prepared oligomers, supporting the relevance of the species herein studied. These results represent an important step toward understanding the connection between AβO size and toxicity. PMID:25343357

  12. Elucidating Molecular Mass and Shape of a Neurotoxic Aβ Oligomer

    PubMed Central

    2015-01-01

    Alzheimer's disease (AD), the most prevalent type of dementia, has been associated with the accumulation of amyloid β oligomers (AβOs) in the central nervous system. AβOs vary widely in size, ranging from dimers to larger than 100 kDa. Evidence indicates that not all oligomers are toxic, and there is yet no consensus on the size of the actual toxic oligomer. Here we used NU4, a conformation-dependent anti-AβO monoclonal antibody, to investigate size and shape of a toxic AβO assembly. By using size-exclusion chromatography and immuno-based detection, we isolated an AβO-NU4 complex amenable for biochemical and morphological studies. The apparent molecular mass of the NU4-targeted oligomer was 80 kDa. Atomic force microscopy imaging of the AβO-NU4 complex showed a size distribution centered at 5.37 nm, an increment of 1.5 nm compared to the size of AβOs (3.85 nm). This increment was compatible with the size of NU4 (1.3 nm), suggesting a 1:1 oligomer to NU4 ratio. NU4-reactive oligomers extracted from AD human brain concentrated in a molecular mass range similar to that found for in vitro prepared oligomers, supporting the relevance of the species herein studied. These results represent an important step toward understanding the connection between AβO size and toxicity. PMID:25343357

  13. Structural and functional properties of prefibrillar α-synuclein oligomers

    PubMed Central

    Pieri, Laura; Madiona, Karine; Melki, Ronald

    2016-01-01

    The deposition of fibrillar alpha-synuclein (α-syn) within inclusions (Lewy bodies and Lewy neurites) in neurons and glial cells is a hallmark of synucleinopathies. α-syn populates a variety of assemblies ranging from prefibrillar oligomeric species to fibrils whose specific contribution to neurodegeneration is still unclear. Here, we compare the specific structural and biological properties of distinct soluble prefibrillar α-syn oligomers formed either spontaneously or in the presence of dopamine and glutaraldehyde. We show that both on-fibrillar assembly pathway and distinct dopamine-mediated and glutaraldehyde-cross-linked α-syn oligomers are only slightly effective in perturbing cell membrane integrity and inducing cytotoxicity, while mature fibrils exhibit the highest toxicity. In contrast to low-molecular weight and unstable oligomers, large stable α-syn oligomers seed the aggregation of soluble α-syn within reporter cells although to a lesser extent than mature α-syn fibrils. These oligomers appear elongated in shape. Our findings suggest that α-syn oligomers represent a continuum of species ranging from unstable low molecular weight particles to mature fibrils via stable elongated oligomers composed of more than 15 α-syn monomers that possess seeding capacity. PMID:27075649

  14. Toxic species in amyloid disorders: Oligomers or mature fibrils

    PubMed Central

    Verma, Meenakshi; Vats, Abhishek; Taneja, Vibha

    2015-01-01

    Protein aggregation is the hallmark of several neurodegenerative disorders. These protein aggregation (fibrillization) disorders are also known as amyloid disorders. The mechanism of protein aggregation involves conformation switch of the native protein, oligomer formation leading to protofibrils and finally mature fibrils. Mature fibrils have long been considered as the cause of disease pathogenesis; however, recent evidences suggest oligomeric intermediates formed during fibrillization to be toxic. In this review, we have tried to address the ongoing debate for these toxic amyloid species. We did an extensive literature search and collated information from Pubmed (http://www.ncbi.nlm.nih.gov) and Google search using various permutations and combinations of the following keywords: Neurodegeneration, amyloid disorders, protein aggregation, fibrils, oligomers, toxicity, Alzheimer's Disease, Parkinson's Disease. We describe different instances showing the toxicity of mature fibrils as well as oligomers in Alzheimer's Disease and Parkinson's Disease. Distinct structural framework and morphology of amyloid oligomers suggests difference in toxic effect between oligomers and fibrils. We highlight the difference in structure and proposed toxicity pathways for fibrils and oligomers. We also highlight the evidences indicating that intermediary oligomeric species can act as potential diagnostic biomarker. Since the formation of these toxic species follow a common structural switch among various amyloid disorders, the protein aggregation events can be targeted for developing broad-range therapeutics. The therapeutic trials based on the understanding of different protein conformers (monomers, oligomers, protofibrils and fibrils) in amyloid cascade are also described. PMID:26019408

  15. A Versatile and Scalable Strategy to Discrete Oligomers.

    PubMed

    Lawrence, Jimmy; Lee, Sang-Ho; Abdilla, Allison; Nothling, Mitchell D; Ren, Jing M; Knight, Abigail S; Fleischmann, Carolin; Li, Youli; Abrams, Austin S; Schmidt, Bernhard V K J; Hawker, Michael C; Connal, Luke A; McGrath, Alaina J; Clark, Paul G; Gutekunst, Will R; Hawker, Craig J

    2016-05-18

    A versatile strategy is reported for the multigram synthesis of discrete oligomers from commercially available monomer families, e.g., acrylates, styrenics, and siloxanes. Central to this strategy is the identification of reproducible procedures for the separation of oligomer mixtures using automated flash chromatography systems with the effectiveness of this approach demonstrated through the multigram preparation of discrete oligomer libraries (Đ = 1.0). Synthetic availability, coupled with accurate structural control, allows these functional building blocks to be harnessed for both fundamental studies as well as targeted technological applications. PMID:27152711

  16. Binding affinity of amyloid oligomers to cellular membranes is a generic indicator of cellular dysfunction in protein misfolding diseases.

    PubMed

    Evangelisti, Elisa; Cascella, Roberta; Becatti, Matteo; Marrazza, Giovanna; Dobson, Christopher M; Chiti, Fabrizio; Stefani, Massimo; Cecchi, Cristina

    2016-01-01

    The conversion of peptides or proteins from their soluble native states into intractable amyloid deposits is associated with a wide range of human disorders. Misfolded protein oligomers formed during the process of aggregation have been identified as the primary pathogenic agents in many such conditions. Here, we show the existence of a quantitative relationship between the degree of binding to neuronal cells of different types of oligomers formed from a model protein, HypF-N, and the GM1 content of the plasma membranes. In addition, remarkably similar behavior is observed for oligomers of the Aβ42 peptide associated with Alzheimer's disease. Further analysis has revealed the existence of a linear correlation between the level of the influx of Ca(2+) across neuronal membranes that triggers cellular damage, and the fraction of oligomeric species bound to the membrane. Our findings indicate that the susceptibility of neuronal cells to different types of misfolded oligomeric assemblies is directly related to the extent of binding of such oligomers to the cellular membrane. PMID:27619987

  17. Ethanol Mediates Cell Cycle Arrest and Apoptosis in SK-N-SH Neuroblastoma Cells

    PubMed Central

    Lee, Maria; Song, Byoung-Joon; Kwon, Yongil

    2014-01-01

    Background: The mechanisms of cell or organ damage by chronic alcohol consumption are still poorly understood. The present study aimed to investigate the role of the mitogen-activated protein kinases during ethanol-induced damage to SK-N-SH neuroblastoma cells. Methods: Cells were treated with ethanol and subsequently analyzed for cell morphology, viability, and DNA fragmentation. Immunoblot analysis was performed to assess various proteins levels associated with cell cycle arrest and apoptosis after ethanol exposure. Results: Ethanol induced time- and dose-dependent cell death in SK-N-SH cells and increased c-Jun N-terminal protein kinase (JNK) activity in a time- and concentration dependent manner. In contrast, p38 kinase activity increased transiently. After treatment with JNK or p38 kinase inhibitors, ethanol-induced cell death significantly reduced. Ethanol-induced cell death was accompanied by increased cytochrome c release and caspase 3 activity observed at 12 h. In contrast, the level of anti-apoptotic Bcl-2 protein did not change. Ethanol also increased the phosphorylation of p53 and p53 activation was followed by an increase in the p21 tumor suppressor protein accompanied by a gradual decrease in phospho-Rb protein. Conclusion: Our results suggest that ethanol mediates apoptosis of neuroblastoma cells by stimulating p53-related cell cycle arrest mediated through activation of the JNK-related pathway. PMID:25337571

  18. Constitutional Ip36 deletion in a child with neuroblastoma

    SciTech Connect

    Biegel, J.A.; Zackai, E.H.; Scher, C.D.; Emanuel, B.S. Univ. of Pennsylvania, Philadelphia ); White, P.S.; Marshall, H.N.; Fujimori, Minoru; Brodeur, G.M. )

    1993-01-01

    The authors describe a child with dysmorphic features, as well as developmental and growth delay, who developed neuroblastoma at 5 mo of age. Cytogenetic analysis of blood lymphocytes revealed an interstitial deletion of 1p36.1 [r arrow] 1p36.2, which was apparent only with high-resolution banding. Molecular analysis with a collection of polymorphic DNA probes for 1p confirmed an interstitial deletion involving subbands of 1p36. Deletions of this region are a common finding in neuroblastoma cells from patients with advanced stages of disease. Therefore, these results (a) suggest that constitutional deletion of this region predisposed the patient to the development of neuroblastoma and (b) support the localization of a neuroblastoma tumor-suppressor locus to 1p36. 48 refs., 2 figs.

  19. Primary pancreatic neuroblastoma presenting with opsoclonus–myoclonus syndrome

    PubMed Central

    Galgano, Samuel; Royal, Stuart

    2015-01-01

    Although neuroblastoma is a common solid organ malignancy in children, primary pancreatic neuroblastoma is a rare entity in children, with very few cases reported in the literature. The case discusses the presentation of a 21-month-old female presenting to the neurology clinic with ataxia and erratic eye movements. Our case illustrates the computed tomography, ultrasound, and scintigraphic findings of primary pancreatic neuroblastoma presenting as opsoclonus–myoclonus syndrome. Computed tomography and ultrasound demonstrated a vascular, enhancing mass in the pancreatic body clearly separate from the adrenal gland. Metaiodobenzylguanidine scan demonstrates focal intense uptake in the pancreatic body. The patient's diagnosis was confirmed with biopsy, and her malignancy responded well to conventional chemotherapy. The case is important in that it demonstrates the unusual imaging appearance of a primary pancreatic neuroblastoma. PMID:26973724

  20. Primary pancreatic neuroblastoma presenting with opsoclonus-myoclonus syndrome.

    PubMed

    Galgano, Samuel; Royal, Stuart

    2016-03-01

    Although neuroblastoma is a common solid organ malignancy in children, primary pancreatic neuroblastoma is a rare entity in children, with very few cases reported in the literature. The case discusses the presentation of a 21-month-old female presenting to the neurology clinic with ataxia and erratic eye movements. Our case illustrates the computed tomography, ultrasound, and scintigraphic findings of primary pancreatic neuroblastoma presenting as opsoclonus-myoclonus syndrome. Computed tomography and ultrasound demonstrated a vascular, enhancing mass in the pancreatic body clearly separate from the adrenal gland. Metaiodobenzylguanidine scan demonstrates focal intense uptake in the pancreatic body. The patient's diagnosis was confirmed with biopsy, and her malignancy responded well to conventional chemotherapy. The case is important in that it demonstrates the unusual imaging appearance of a primary pancreatic neuroblastoma. PMID:26973724

  1. A catecholamine-secreting neuroblastoma leading to hydrops fetalis.

    PubMed

    Inoue, T; Ito, Y; Nakamura, T; Matsuoka, K; Sago, H

    2014-05-01

    A case of fetal neuroblastoma of the right adrenal gland, with rapid development of hydrops fetalis due to catecholamine-induced cardiomyopathy, is reported. A fetus with a right suprarenal mass detected during ultrasonography at 32 weeks gestation progressively developed into hydrops fetalis by 35.2 weeks gestation. An emergent cesarean section was performed. At birth, the female neonate was hypertensive, with markedly elevated catecholamine levels; echocardiography showed poor contractility. Morphine, human atrial natriuretic peptide, milrinone, nitroprusside and dobutamine were initiated and her blood pressure was maintained within the normal range and her cardiac contractility improved 2 weeks after birth. Neuroblastoma cells were detected in the placenta, resulting in the right adrenal mass being diagnosed as a neuroblastoma. She was well, and the mass diminished in size within 4 months, without surgery. A fetus with suspected neuroblastoma, indicated by a suprarenal mass, should be managed with appropriate consideration of hydrops. PMID:24776602

  2. TERT rearrangements are frequent in neuroblastoma and identify aggressive tumors.

    PubMed

    Valentijn, Linda J; Koster, Jan; Zwijnenburg, Danny A; Hasselt, Nancy E; van Sluis, Peter; Volckmann, Richard; van Noesel, Max M; George, Rani E; Tytgat, Godelieve A M; Molenaar, Jan J; Versteeg, Rogier

    2015-12-01

    Whole-genome sequencing detected structural rearrangements of TERT in 17 of 75 high-stage neuroblastomas, with five cases resulting from chromothripsis. Rearrangements were associated with increased TERT expression and targeted regions immediately up- and downstream of TERT, positioning a super-enhancer close to the breakpoints in seven cases. TERT rearrangements (23%), ATRX deletions (11%) and MYCN amplifications (37%) identify three almost non-overlapping groups of high-stage neuroblastoma, each associated with very poor prognosis. PMID:26523776

  3. Scintigraphy of a neuroblastoma with I-131 meta-iodobenzylguanidine

    SciTech Connect

    Kimmig, B.; Brandeis, W.E.; Eisenhut, M.; Bubeck, B.; Hermann, H.J.; Zum Winkel, K.

    1984-07-01

    Radioiodinated m-iodobenzylguanidine has been applied mainly for the diagnosis of pheochromocytoma and blastoma. In this paper the authors show that an ontogenetically related tumor, the neuroblastoma, is also scintigraphically visualized by its high uptake of I-131 MIBG. Because of the kinetic findings and the high uptake of more than 30% of the injected activity, it is likely that the neuroblastoma, by analogy with pheochromocytoma, is susceptible to specific radionuclide therapy.

  4. Scintigraphy of a neuroblastoma with I-131 meta-iodobenzylguanidine

    SciTech Connect

    Kimmig, B.; Brandeis, W.E.; Eisenhut, M.; Bubeck, B.; Hermann, H.J.; zum Winkel, K.

    1984-07-01

    Radioiodinated m-iodobenzylguanidine has been applied mainly for the diagnosis of pheochromocytoma and blastoma. In this paper the author shows that an ontogenetically related tumor, the neuroblastoma, is also scintigraphically visualized by its high uptake of I-131 MIBG. Because of the kinetic findings and the high uptake of more than 30% of the injected activity, it is likely that the neuroblastoma, by analogy with pheochromocytoma, is susceptible to specific radionuclide therapy.

  5. Immune response to racotumomab in a child with relapsed neuroblastoma

    PubMed Central

    Sampor, C.; Guthmann, M. D.; Scursoni, A.; Cacciavillano, W.; Torbidoni, A.; Galluzzo, L.; Camarero, S.; Lopez, J.; de Dávila, M. T. G.; Fainboim, L.; Chantada, G. L.

    2012-01-01

    Immunotherapy targeting ganglioside antigens is a powerful tool for the treatment of high risk neuroblastoma. However, only treatment with anti-GD2 antibodies has been used in clinical practice and other options may be pursued. We report the use of racotumomab, an anti-idiotype vaccine against N-glycolyl neuraminic acid (NeuGc)- containing gangliosides, eliciting an immune response in a child with relapsed neuroblastoma expressing the NeuGcGM3 ganglioside. PMID:23267436

  6. Synchronous Ipsilateral Wilms’ Tumor and Neuroblastoma in an Infant

    PubMed Central

    Thakkar, Nirali Chirag; Sinha, Shalini

    2016-01-01

    Wilms’ tumor (WT) and neuroblastoma (NB), the two most common extra-cranial solid malignant tumors, are seldom seen together in the same patient. A 10-month girl presented with a right retroperitoneal mass. A preoperative diagnosis of Wilms’ tumor (WT) was made. She was given preoperative chemotherapy followed by surgery. At surgery a renal mass (WT) and a suprarenal mass (neuroblastoma – NB) were removed. She finally succumbed to metastatic NB in the postoperative period. PMID:26816675

  7. Biomimetic peptoid oligomers as dual-action antifreeze agents.

    PubMed

    Huang, Mia L; Ehre, David; Jiang, Qi; Hu, Chunhua; Kirshenbaum, Kent; Ward, Michael D

    2012-12-01

    The ability of natural peptides and proteins to influence the formation of inorganic crystalline materials has prompted the design of synthetic compounds for the regulation of crystal growth, including the freezing of water and growth of ice crystals. Despite their versatility and ease of structural modification, peptidomimetic oligomers have not yet been explored extensively as crystallization modulators. This report describes a library of synthetic N-substituted glycine peptoid oligomers that possess "dual-action" antifreeze activity as exemplified by ice crystal growth inhibition concomitant with melting temperature reduction. We investigated the structural features responsible for these phenomena and observed that peptoid antifreeze activities depend both on oligomer backbone structure and side chain chemical composition. These studies reveal the capability of peptoids to act as ice crystallization regulators, enabling the discovery of a unique and diverse family of synthetic oligomers with potential as antifreeze agents in food production and biomedicine. PMID:23169638

  8. Chemical Fluorescent Probe for Detection of Aβ Oligomers.

    PubMed

    Teoh, Chai Lean; Su, Dongdong; Sahu, Srikanta; Yun, Seong-Wook; Drummond, Eleanor; Prelli, Frances; Lim, Sulgi; Cho, Sunhee; Ham, Sihyun; Wisniewski, Thomas; Chang, Young-Tae

    2015-10-28

    Aggregation of amyloid β-peptide (Aβ) is implicated in the pathology of Alzheimer's disease (AD), with the soluble, Aβ oligomeric species thought to be the critical pathological species. Identification and characterization of intermediate species formed during the aggregation process is crucial to the understanding of the mechanisms by which oligomeric species mediate neuronal toxicity and following disease progression. Probing these species proved to be extremely challenging, as evident by the lack of reliable sensors, due to their heterogeneous and transient nature. We describe here an oligomer-specific fluorescent chemical probe, BoDipy-Oligomer (BD-Oligo), developed through the use of the diversity-oriented fluorescent library approach (DOFLA) and high-content, imaging-based screening. This probe enables dynamic oligomer monitoring during fibrillogenesis in vitro and shows in vivo Aβ oligomers staining possibility in the AD mice model. PMID:26218347

  9. PHOX2B is a suppressor of neuroblastoma metastasis

    PubMed Central

    Naftali, Osnat; Maman, Shelly; Meshel, Tsipi; Sagi-Assif, Orit; Ginat, Ravit; Witz, Isaac P.

    2016-01-01

    Paired like homeobox 2B (PHOX2B) is a minimal residual disease (MRD) marker of neuroblastoma. The presence of MRD, also referred to as micro-metastases, is a powerful marker of poor prognosis in neuroblastoma. Lung metastasis is considered a terminal event in neuroblastoma. Lung micro-metastatic neuroblastoma (MicroNB) cells show high expression levels of PHOX2B and possess a less malignant and metastatic phenotype than lung macro metastatic neuroblastoma (MacroNB) cells, which hardly express PHOX2B. In vitro assays showed that PHOX2B knockdown in MicroNB cells did not affect cell viability; however it decreased the migratory capacity of the MicroNB-shPHOX2B cells. An orthotopic inoculation of MicroNB-shPHOX2B cells into the adrenal gland of nude mice resulted in significantly larger primary tumors and a heavier micro-metastatic load in the lungs and bone-marrow, than when control cells were inoculated. PHOX2B expression was found to be regulated by methylation. The PHOX2B promoter in MacroNB cells is significantly more methylated than in MicroNB cells. Demethylation assays using 5-azacytidine demonstrated that methylation can indeed inhibit PHOX2B transcription in MacroNB cells. These pre-clinical data strongly suggest that PHOX2B functions as a suppressor of neuroblastoma progression. PMID:26840262

  10. Fractionated total body irradiation for metastatic neuroblastoma

    SciTech Connect

    Kun, L.E.; Casper, J.T.; Kline, R.W.; Piaskowski, V.D.

    1981-11-01

    Twelve patients over one year old with neuroblastoma (NBL) metastatic to bone and bone marrow entered a study of adjuvant low-dose, fractionated total body irradiation (TBI). Six children who achieved a ''complete clinical response'' following chemotherapy (cyclophosphamide and adriamycin) and surgical resection of the abdominal primary received TBI (10 rad/fraction to totals of 100-120 rad/10-12 fx/12-25 days). Two children received concurrent local irradiation for residual abdominal tumor. The intervals from cessation of chemotherapy to documented progression ranged from 2-16 months, not substatially different from patients receiving similar chemotherapy and surgery without TBI. Three additional children with progressive NBL received similar TBI (80-120 rad/8-12 fx) without objective response.

  11. Exosomal cell-to-cell transmission of alpha synuclein oligomers

    PubMed Central

    2012-01-01

    Background Aggregation of alpha-synuclein (αsyn) and resulting cytotoxicity is a hallmark of sporadic and familial Parkinson’s disease (PD) as well as dementia with Lewy bodies, with recent evidence implicating oligomeric and pre-fibrillar forms of αsyn as the pathogenic species. Recent in vitro studies support the idea of transcellular spread of extracellular, secreted αsyn across membranes. The aim of this study is to characterize the transcellular spread of αsyn oligomers and determine their extracellular location. Results Using a novel protein fragment complementation assay where αsyn is fused to non-bioluminescent amino-or carboxy-terminus fragments of humanized Gaussia Luciferase we demonstrate here that αsyn oligomers can be found in at least two extracellular fractions: either associated with exosomes or free. Exosome-associated αsyn oligomers are more likely to be taken up by recipient cells and can induce more toxicity compared to free αsyn oligomers. Specifically, we determine that αsyn oligomers are present on both the outside as well as inside of exosomes. Notably, the pathway of secretion of αsyn oligomers is strongly influenced by autophagic activity. Conclusions Our data suggest that αsyn may be secreted via different secretory pathways. We hypothesize that exosome-mediated release of αsyn oligomers is a mechanism whereby cells clear toxic αsyn oligomers when autophagic mechanisms fail to be sufficient. Preventing the early events in αsyn exosomal release and uptake by inducing autophagy may be a novel approach to halt disease spreading in PD and other synucleinopathies. PMID:22920859

  12. Proton-Beam Therapy for Olfactory Neuroblastoma

    SciTech Connect

    Nishimura, Hideki . E-mail: westvill@med.kobe-u.ac.jp; Ogino, Takashi; Kawashima, Mitsuhiko; Nihei, Keiji; Arahira, Satoko; Onozawa, Masakatsu; Katsuta, Shoichi; Nishio, Teiji

    2007-07-01

    Purpose: To analyze the feasibility and efficacy of proton-beam therapy (PBT) for olfactory neuroblastoma (ONB) as a definitive treatment, by reviewing our preliminary experience. Olfactory neuroblastoma is a rare disease, and a standard treatment strategy has not been established. Radiation therapy for ONB is challenging because of the proximity of ONBs to critical organs. Proton-beam therapy can provide better dose distribution compared with X-ray irradiation because of its physical characteristics, and is deemed to be a feasible treatment modality. Methods and Materials: A retrospective review was performed on 14 patients who underwent PBT for ONB as definitive treatment at the National Cancer Center Hospital East (Kashiwa, Chiba, Japan) from November 1999 to February 2005. A total dose of PBT was 65 cobalt Gray equivalents (Gy{sub E}), with 2.5-Gy{sub E} once-daily fractionations. Results: The median follow-up period for surviving patients was 40 months. One patient died from disseminated disease. There were two persistent diseases, one of which was successfully salvaged with surgery. The 5-year overall survival rate was 93%, the 5-year local progression-free survival rate was 84%, and the 5-year relapse-free survival rate was 71%. Liquorrhea was observed in one patient with Kadish's stage C disease (widely destroying the skull base). Most patients experienced Grade 1 to 2 dermatitis in the acute phase. No other adverse events of Grade 3 or greater were observed according to the RTOG/EORTC acute and late morbidity scoring system. Conclusions: Our preliminary results of PBT for ONB achieved excellent local control and survival outcomes without serious adverse effects. Proton-beam therapy is considered a safe and effective modality that warrants further study.

  13. Natural killer cells facilitate PRAME-specific T-cell reactivity against neuroblastoma

    PubMed Central

    Spel, Lotte; Boelens, Jaap-Jan; van der Steen, Dirk M.; Blokland, Nina J.G.; van Noesel, Max M.; Molenaar, Jan J.; Heemskerk, Mirjam H.M.

    2015-01-01

    Neuroblastoma is the most common solid tumor in children with an estimated 5-year progression free survival of 20–40% in stage 4 disease. Neuroblastoma actively avoids recognition by natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Although immunotherapy has gained traction for neuroblastoma treatment, these immune escape mechanisms restrain clinical results. Therefore, we aimed to improve neuroblastoma immunogenicity to further the development of antigen-specific immunotherapy against neuroblastoma. We found that neuroblastoma cells significantly increase surface expression of MHC I upon exposure to active NK cells which thereby readily sensitize neuroblastoma cells for recognition by CTLs. We show that oncoprotein PRAME serves as an immunodominant antigen for neuroblastoma as NK-modulated neuroblastoma cells are recognized by PRAMESLLQHLIGL/A2-specific CTL clones. Furthermore, NK cells induce MHC I upregulation in neuroblastoma through contact-dependent secretion of IFNγ. Our results demonstrate remarkable plasticity in the peptide/MHC I surface expression of neuroblastoma cells, which is reversed when neuroblastoma cells experience innate immune attack by sensitized NK cells. These findings support the exploration of NK cells as adjuvant therapy to enforce neuroblastoma-specific CTL responses. PMID:26452036

  14. Optimizing antisense oligonucleotides using phosphorodiamidate morpholino oligomers.

    PubMed

    Popplewell, Linda J; Malerba, Alberto; Dickson, George

    2012-01-01

    Duchenne muscular dystrophy (DMD) is caused by mutations that disrupt the reading frame of the human DMD gene. Selective removal of exons flanking an out-of-frame DMD mutation can result in an in-frame mRNA transcript that may be translated into an internally deleted Becker muscular dystrophy-like functionally active dystrophin protein with therapeutic activity. Antisense oligonucleotides (AOs) can be designed to bind to complementary sequences in the targeted mRNA and modify pre-mRNA splicing to correct the reading frame of a mutated transcript. AO-induced exon skipping resulting in functional truncated dystrophin has been demonstrated in animal models of DMD both in vitro and in vivo, in DMD patient cells in vitro in culture, and in DMD muscle explants. The recent advances made in this field suggest that it is likely that AO-induced exon skipping will be the first gene therapy for DMD to reach the clinic. However, it should be noted that personalized molecular medicine may be necessary, since the various reading frame-disrupting mutations are spread across the DMD gene. The different deletions that cause DMD would require skipping of different exons, which would require the optimization and clinical trial workup of many specific AOs. This chapter describes the methodologies available for the optimization of AOs, in particular phosphorodiamidate morpholino oligomers, for the targeted skipping of specific exons on the DMD gene. PMID:22454060

  15. Cross-linking of glycoprotein oligomers during herpes simplex virus type 1 entry.

    PubMed

    Handler, C G; Cohen, G H; Eisenberg, R J

    1996-09-01

    Herpes simplex virus (HSV) has 10 glycoproteins in its envelope. Glycoprotein B (gB), gC, gD, gH, and gL have been implicated in virus entry. We previously used chemical cross-linking to show that these five glycoproteins were close enough to each other to be cross-linked into homodimeric and hetero-oligomeric forms; hetero-oligomers of gB-gC, gC-gD, gD-gB, gH-gL, gC-gL and gD-gL were found in purified virions. To better understand the roles of these glycoproteins in viral entry, we have modified a standard HSV penetration assay to include cross-linkers. This allowed us to examine changes in associations of viral glycoproteins during the entry process. HSV-1(KOS) was adsorbed at 4 degrees C to human neuroblastoma cells (SY5Y). The temperature was raised to 37 degrees C and cells were treated with cross-linker at various times after the temperature shift. Cytoplasmic extracts were examined by Western blotting (immunoblotting) for viral glycoproteins. We found that (i) as in virus alone, the length and concentration of the cross-linking agent affected the number of specific complexes isolated; (ii) the same glycoprotein patterns found in purified virions were also present after attachment of virions to cells; and (iii) the ability to cross-link HSV glycoproteins changed as virus penetration proceeded, e.g., gB and gD complexes which were present during attachment disappeared with increasing time, and their disappearance paralleled the kinetics of penetration. However, this phenomenon appeared to be selective since it was not observed with gC oligomers. In addition, we examined the cross-linking patterns of gB and gD in null viruses K082 and KOSgD beta. Neither of these mutants, which attach but cannot penetrate, showed changes in glycoprotein cross-linking over time. We speculate that these changes are due to conformational changes which preclude cross-linking or spatial alterations which dissociate the glycoprotein interactions during the penetration events. PMID

  16. UBE4B Levels Are Correlated with Clinical Outcomes in Neuroblastoma Patients and with Altered Neuroblastoma Cell Proliferation and Sensitivity to EGFR Inhibitors

    PubMed Central

    Zage, Peter E.; Sirisaengtaksin, Natalie; Liu, Yin; Gireud, Monica; Brown, Brandon S.; Palla, Shana; Richards, Kristen N.; Hughes, Dennis P.M.; Bean, Andrew J.

    2012-01-01

    Background The UBE4B gene, located on chromosome 1p36, encodes a ubiquitin ligase that interacts with Hrs, a protein involved in EGFR trafficking, suggesting a link between EGFR trafficking and neuroblastoma pathogenesis. We have analyzed the roles of UBE4B in the outcomes of neuroblastoma patients and in neuroblastoma tumor cell proliferation, EGFR trafficking, and response to EGFR inhibition. Methods We examined the association of UBE4B expression with neuroblastoma patient survival using available microarray datasets. We measured UBE4B and EGFR protein levels in patient tumor samples and EGFR degradation rates in neuroblastoma cell lines and analyzed the effects of UBE4B on neuroblastoma tumor cell growth. The effects of the EGFR inhibitor cetuximab were examined in neuroblastoma cells expressing wild-type and mutant UBE4B. Results Low UBE4B gene expression is associated with poor outcomes in patients with neuroblastoma. UBE4B overexpression reduced neuroblastoma tumor cell proliferation, and UBE4B expression was inversely related to EGFR expression in patient tumor samples. EGFR degradation rates correlated with cellular UBE4B levels. Enhanced expression of catalytically active UBE4B resulted in reduced sensitivity to EGFR inhibition. Conclusions We have demonstrated associations between UBE4B expression and neuroblastoma patient outcomes and between UBE4B and EGFR expression in neuroblastoma tumor samples. Moreover, levels of UBE4B influenced neuroblastoma tumor cell proliferation, EGFR degradation, and response to EGFR inhibition. These results suggest UBE4B-mediated GFR trafficking may contribute to the poor prognosis of neuroblastoma tumors with 1p36 deletions, and that UBE4B expression may be a marker that can predict responses of neuroblastoma tumors to treatment. PMID:22990745

  17. Inhibition of hemopoiesis in vitro by neuroblastoma-derived gangliosides.

    PubMed

    Sietsma, H; Nijhof, W; Dontje, B; Vellenga, E; Kamps, W A; Kok, J W

    1998-11-01

    Hemopoiesis is disturbed in bone marrow-involving cancers like leukemia and neuroblastoma. Shedding of gangliosides by tumor cells may contribute to this tumor-induced bone marrow suppression. We studied in vitro the inhibitory effects of murine neuroblastoma cells (Neuro-2a and C1300) and their gangliosides on hemopoiesis using normal murine hemopoietic progenitor colony-forming assays. Transwell cultured neuroblastoma cells showed a dose-dependent inhibition on hemopoiesis, indicating that a soluble factor was responsible for this effect. Furthermore, the supernatant of Neuro-2a cultured cells inhibited hemopoietic proliferation and differentiation. To determine whether the inhibitory effect was indeed due to shed gangliosides and not, for instance, caused by cytokines, the effect of DL-threo-1 -phenyl-2-decanoylamino-3-morpholino-1-propanol (DL-PDMP) on Neuro-2a cells was studied. DL-PDMP is a potent inhibitor of glucosylceramide synthase, resulting in inhibition of the synthesis and shedding of gangliosides. The initially observed inhibitory effect of supernatant of Neuro-2a cells was abrogated by culturing these cells for 3 days in the presence of 10 microM DL-PDMP. Moreover, gangliosides isolated from Neuro-2a cell membranes inhibited hemopoietic growth. To determine whether the described phenomena in vitro are a reflection of bone marrow suppression occurring in vivo, gangliosides isolated from plasma of neuroblastoma patients were tested for their effects on human hemopoietic progenitor colony-forming assays. These human neuroblastoma-derived gangliosides inhibited normal erythropoiesis (colony-forming unit-erythroid/burst-forming unit-erythroid) and myelopoiesis (colony-forming unit-granulocyte/macrophage) to a higher extent compared with gangliosides isolated from control plasma. Altogether these results suggest that gangliosides shed by neuroblastoma cells inhibit hemopoiesis and may contribute to the observed bone marrow depression in neuroblastoma

  18. Telomerase activation by genomic rearrangements in high-risk neuroblastoma

    PubMed Central

    Peifer, Martin; Hertwig, Falk; Roels, Frederik; Dreidax, Daniel; Gartlgruber, Moritz; Menon, Roopika; Krämer, Andrea; Roncaioli, Justin L.; Sand, Frederik; Heuckmann, Johannes M.; Ikram, Fakhera; Schmidt, Rene; Ackermann, Sandra; Engesser, Anne; Kahlert, Yvonne; Vogel, Wenzel; Altmüller, Janine; Nürnberg, Peter; Thierry-Mieg, Jean; Thierry-Mieg, Danielle; Mariappan, Aruljothi; Heynck, Stefanie; Mariotti, Erika; Henrich, Kai-Oliver; Glöckner, Christian; Bosco, Graziella; Leuschner, Ivo; Schweiger, Michal R.; Savelyeva, Larissa; Watkins, Simon C.; Shao, Chunxuan; Bell, Emma; Höfer, Thomas; Achter, Viktor; Lang, Ulrich; Theissen, Jessica; Volland, Ruth; Saadati, Maral; Eggert, Angelika; de Wilde, Bram; Berthold, Frank; Peng, Zhiyu; Zhao, Chen; Shi, Leming; Ortmann, Monika; Büttner, Reinhard; Perner, Sven; Hero, Barbara; Schramm, Alexander; Schulte, Johannes H.; Herrmann, Carl; O’Sullivan, Roderick J.; Westermann, Frank; Thomas, Roman K.; Fischer, Matthias

    2016-01-01

    Neuroblastoma is a malignant paediatric tumour of the sympathetic nervous system1. Roughly half of these tumours regress spontaneously or are cured by limited therapy. By contrast, high-risk neuroblastomas have an unfavourable clinical course despite intensive multimodal treatment, and their molecular basis has remained largely elusive2–4. Here we have performed whole-genome sequencing of 56 neuroblastomas (high-risk, n = 39; low-risk, n = 17) and discovered recurrent genomic rearrangements affecting a chromosomal region at 5p15.33 proximal of the telomerase reverse transcriptase gene (TERT). These rearrangements occurred only in high-risk neuroblastomas (12/39, 31%) in a mutually exclusive fashion with MYCN amplifications and ATRX mutations, which are known genetic events in this tumour type1,2,5. In an extended case series (n = 217), TERT rearrangements defined a subgroup of high-risk tumours with particularly poor outcome. Despite a large structural diversity of these rearrangements, they all induced massive transcriptional upregulation of TERT. In the remaining high-risk tumours, TERT expression was also elevated in MYCN-amplified tumours, whereas alternative lengthening of telomeres was present in neuroblastomas without TERT or MYCN alterations, suggesting that telomere lengthening represents a central mechanism defining this subtype. The 5p15.33 rearrangements juxtapose the TERT coding sequence to strong enhancer elements, resulting in massive chromatin remodelling and DNA methylation of the affected region. Supporting a functional role of TERT, neuroblastoma cell lines bearing rearrangements or amplified MYCN exhibited both upregulated TERT expression and enzymatic telomerase activity. In summary, our findings show that remodelling of the genomic context abrogates transcriptional silencing of TERT in high-risk neuroblastoma and places telomerase activation in the centre of transformation in a large fraction of these tumours. PMID:26466568

  19. Identification of ALK as the Major Familial Neuroblastoma Predisposition Gene

    PubMed Central

    Mossë, Yalë P; Laudenslager, Marci; Longo, Luca; Cole, Kristina A; Wood, Andrew; Attiyeh, Edward F; Laquaglia, Michael J; Sennett, Rachel; Lynch, Jill E; Perri, Patrizia; Laureys, Geneviève; Speleman, Frank; Hakonarson, Hakon; Torkamani, Ali; Schork, Nicholas J; Brodeur, Garrett M; Tonini, Gian Paolo; Rappaport, Eric; Devoto, Marcella; Maris, John M

    2009-01-01

    SUMMARY Survival rates for the childhood cancer neuroblastoma have not substantively improved despite dramatic escalation in chemotherapy intensity. Like most human cancers, this embryonal malignancy can be inherited, but the genetic etiology of familial and sporadically occurring neuroblastoma was largely unknown. Here we show that germline mutations in the anaplastic lymphoma kinase gene (ALK) explain the majority of hereditary neuroblastomas, and that activating mutations can also be somatically acquired. We first identified a significant linkage signal at the short arm of chromosome 2 (maximum nonparametric LOD=4.23 at rs1344063) using a whole-genome scan in neuroblastoma pedigrees. Resequencing of regional candidate genes identified three separate missense mutations in the tyrosine kinase domain of ALK (G1128A, R1192P and R1275Q) that segregated with the disease in eight separate families. Examination of 491 sporadically occurring human neuroblastoma samples showed that the ALK locus was gained in 22.8%, and highly amplified in an additional 3.3%, and that these aberrations were highly associated with death from disease (P=0.0003). Resequencing of 194 high-risk neuroblastoma samples showed somatically acquired mutations within the tyrosine kinase domain in 12.4%. Nine of the ten mutations map to critical regions of the kinase domain and were predicted to be oncogenic drivers with high probability. Mutations resulted in constitutive phosphorylation consistent with activation, and targeted knockdown of ALK mRNA resulted in profound growth inhibition of 4 of 4 cell lines harboring mutant or amplified ALK, as well as 2 of 6 wild type for ALK. Our results demonstrate that heritable mutations of ALK are the major cause of familial neuroblastoma, and that germline or acquired activation of this cell surface kinase is a tractable therapeutic target for this lethal pediatric malignancy. PMID:18724359

  20. Telomerase activation by genomic rearrangements in high-risk neuroblastoma.

    PubMed

    Peifer, Martin; Hertwig, Falk; Roels, Frederik; Dreidax, Daniel; Gartlgruber, Moritz; Menon, Roopika; Krämer, Andrea; Roncaioli, Justin L; Sand, Frederik; Heuckmann, Johannes M; Ikram, Fakhera; Schmidt, Rene; Ackermann, Sandra; Engesser, Anne; Kahlert, Yvonne; Vogel, Wenzel; Altmüller, Janine; Nürnberg, Peter; Thierry-Mieg, Jean; Thierry-Mieg, Danielle; Mariappan, Aruljothi; Heynck, Stefanie; Mariotti, Erika; Henrich, Kai-Oliver; Gloeckner, Christian; Bosco, Graziella; Leuschner, Ivo; Schweiger, Michal R; Savelyeva, Larissa; Watkins, Simon C; Shao, Chunxuan; Bell, Emma; Höfer, Thomas; Achter, Viktor; Lang, Ulrich; Theissen, Jessica; Volland, Ruth; Saadati, Maral; Eggert, Angelika; de Wilde, Bram; Berthold, Frank; Peng, Zhiyu; Zhao, Chen; Shi, Leming; Ortmann, Monika; Büttner, Reinhard; Perner, Sven; Hero, Barbara; Schramm, Alexander; Schulte, Johannes H; Herrmann, Carl; O'Sullivan, Roderick J; Westermann, Frank; Thomas, Roman K; Fischer, Matthias

    2015-10-29

    Neuroblastoma is a malignant paediatric tumour of the sympathetic nervous system. Roughly half of these tumours regress spontaneously or are cured by limited therapy. By contrast, high-risk neuroblastomas have an unfavourable clinical course despite intensive multimodal treatment, and their molecular basis has remained largely elusive. Here we have performed whole-genome sequencing of 56 neuroblastomas (high-risk, n = 39; low-risk, n = 17) and discovered recurrent genomic rearrangements affecting a chromosomal region at 5p15.33 proximal of the telomerase reverse transcriptase gene (TERT). These rearrangements occurred only in high-risk neuroblastomas (12/39, 31%) in a mutually exclusive fashion with MYCN amplifications and ATRX mutations, which are known genetic events in this tumour type. In an extended case series (n = 217), TERT rearrangements defined a subgroup of high-risk tumours with particularly poor outcome. Despite a large structural diversity of these rearrangements, they all induced massive transcriptional upregulation of TERT. In the remaining high-risk tumours, TERT expression was also elevated in MYCN-amplified tumours, whereas alternative lengthening of telomeres was present in neuroblastomas without TERT or MYCN alterations, suggesting that telomere lengthening represents a central mechanism defining this subtype. The 5p15.33 rearrangements juxtapose the TERT coding sequence to strong enhancer elements, resulting in massive chromatin remodelling and DNA methylation of the affected region. Supporting a functional role of TERT, neuroblastoma cell lines bearing rearrangements or amplified MYCN exhibited both upregulated TERT expression and enzymatic telomerase activity. In summary, our findings show that remodelling of the genomic context abrogates transcriptional silencing of TERT in high-risk neuroblastoma and places telomerase activation in the centre of transformation in a large fraction of these tumours. PMID:26466568

  1. Identification of GALNT14 as a novel neuroblastoma predisposition gene.

    PubMed

    De Mariano, Marilena; Gallesio, Roberta; Chierici, Marco; Furlanello, Cesare; Conte, Massimo; Garaventa, Alberto; Croce, Michela; Ferrini, Silvano; Tonini, Gian Paolo; Longo, Luca

    2015-09-22

    Although several genes have been associated to neuroblastoma (NB) predisposition and aggressiveness, further genes are likely involved in the overall risk of developing this pediatric cancer. We thus carried out whole-exome sequencing on germline DNA from two affected second cousins and two unlinked healthy relatives from a large family with hereditary NB. Bioinformatics analysis revealed 6999 variations that were exclusively shared by the two familial NB cases. We then considered for further analysis all unknown or rare missense mutations, which involved 30 genes. Validation and analysis of these variants led to identify a GALNT14 mutation (c.802C > T) that properly segregated in the family and was predicted as functionally damaging by PolyPhen2 and SIFT. Screening of 8 additional NB families and 167 sporadic cases revealed this GALNT14 mutation in the tumors of two twins and in the germline of one sporadic NB patient. Moreover, a significant association between MYCN amplification and GALNT14 expression was observed in both NB patients and cell lines. Also, GALNT14 higher expression is associated with a worse OS in a public dataset of 88 NB samples (http://r2.amc.nl). GALNT14 is a member of the polypeptide N-acetylgalactosaminyl-transferase family and maps closely to ALK on 2p23.1, a region we previously discovered in linkage with NB in the family here considered. The aberrant function of GALNTs can result in altered glycoproteins that have been associated to the promotion of tumor aggressiveness in various cancers. Although rare, the recurrence of this mutation suggests GALNT14 as a novel gene potentially involved in NB predisposition. PMID:26309160

  2. Identification of GALNT14 as a novel neuroblastoma predisposition gene

    PubMed Central

    Chierici, Marco; Furlanello, Cesare; Conte, Massimo; Garaventa, Alberto; Croce, Michela; Ferrini, Silvano; Tonini, Gian Paolo; Longo, Luca

    2015-01-01

    Although several genes have been associated to neuroblastoma (NB) predisposition and aggressiveness, further genes are likely involved in the overall risk of developing this pediatric cancer. We thus carried out whole-exome sequencing on germline DNA from two affected second cousins and two unlinked healthy relatives from a large family with hereditary NB. Bioinformatics analysis revealed 6999 variations that were exclusively shared by the two familial NB cases. We then considered for further analysis all unknown or rare missense mutations, which involved 30 genes. Validation and analysis of these variants led to identify a GALNT14 mutation (c.802C > T) that properly segregated in the family and was predicted as functionally damaging by PolyPhen2 and SIFT. Screening of 8 additional NB families and 167 sporadic cases revealed this GALNT14 mutation in the tumors of two twins and in the germline of one sporadic NB patient. Moreover, a significant association between MYCN amplification and GALNT14 expression was observed in both NB patients and cell lines. Also, GALNT14 higher expression is associated with a worse OS in a public dataset of 88 NB samples (http://r2.amc.nl). GALNT14 is a member of the polypeptide N-acetylgalactosaminyl-transferase family and maps closely to ALK on 2p23.1, a region we previously discovered in linkage with NB in the family here considered. The aberrant function of GALNTs can result in altered glycoproteins that have been associated to the promotion of tumor aggressiveness in various cancers. Although rare, the recurrence of this mutation suggests GALNT14 as a novel gene potentially involved in NB predisposition. PMID:26309160

  3. Density functional theory study of neutral and oxidized thiophene oligomers

    NASA Astrophysics Data System (ADS)

    Dai, Yafei; Wei, Chengwei; Blaisten-Barojas, Estela

    2013-11-01

    The effect of oxidation on the energetics and structure of thiophene (Th) oligomers is studied with density functional theory at the B3PW91/6-311++G(d,p) level. Neutral n-Th oligomers (2 < n < 13) are gently curved planar chains. Ionization potential and electron affinity results show that n-Th oligomers are easier to be oxidized as their chain length increases. Oxidation states +2, +4, +6, and +8 are energetically stable in 12-Th. Upon oxidation the conjugated backbone of 12-Th switches from extended benzenoid phase to quinoid phase localized on groups of monomers regularly spaced along the chain. Oxidized states +2, +4, +6, and +8 of 12-Th display two +1e localized at the ends of their chains only because of the finite size of the chains. In 12-Th this end-effect extends over the two terminal monomers forming a positive-negative charge duet. This peculiar charge localization makes n-Th oligomers different from other conducting polymers with similar structure, such as polypyrrole. The spectrum of single-electron molecular states of oxidized 12-Th displays two localized single-electron states in the HOMO-LUMO energy gap per +2 oxidation state. Oligothiophene 12-Th doped with F atoms at 1:2 concentration presents a charge transfer of 3.4 e from oligomer to dopants that increases to 4.8 e in the presence of solvent. The charge distribution in these F-doped oligomers is similar to the +4 oxidation state of 12-Th. It is predicted that dopants produce an enhanced charge transfer localized in the proximity of their locations enhancing the formation of bipolarons in the central part of the oligomer chain.

  4. Weightlessness influences the cytoskeleton and ROS level in SH-SY5Y neuroblastoma cells

    NASA Astrophysics Data System (ADS)

    Bo, Wang; Lina, Qu; Yingxian, Li; Qi, Li; Lei, Bi; Yinghui, Li

    During Spaceflight the nerve system of astronauts was obviously influenced To investigate how gravity effects nerve system the SH-SY5Y neuroblastoma cells were taken as research object By utilizing clinostat and parabolic flight for the model of gravity changing the level of reactive oxygen species was assayed in different time under simulated microgravity the cytomorphology and cytoskeleton of SH-SY5Y neuroblastoma cells were also observed after parabolic flight and clinostat by the conventional and the confocal laser scanning microscope The data showed that ROS level was enhanced and the cytoskeleton was damaged which microfilaments and microtubules were highly disorganized the cell shape was deteriorated under simulated microgravity indicating the relativity between the ROS level fluctuating and cytoskeleton changing It illuminates signal transduction disturbed by oxidative stress also regulates the cytoskeleton changing in SH-SY5Y cells The results suggest the cytoskeleton which is the receptor for sensing gravity was also regulated by cellular redox state which clues on the complexity of cell for self-adjusting to gravity changing

  5. A PCNA-Derived Cell Permeable Peptide Selectively Inhibits Neuroblastoma Cell Growth

    PubMed Central

    Gu, Long; Smith, Shanna; Li, Caroline; Hickey, Robert J.; Stark, Jeremy M.; Fields, Gregg B.; Lang, Walter H.; Sandoval, John A.; Malkas, Linda H.

    2014-01-01

    Proliferating cell nuclear antigen (PCNA), through its interaction with various proteins involved in DNA synthesis, cell cycle regulation, and DNA repair, plays a central role in maintaining genome stability. We previously reported a novel cancer associated PCNA isoform (dubbed caPCNA), which was significantly expressed in a broad range of cancer cells and tumor tissues, but not in non-malignant cells. We found that the caPCNA-specific antigenic site lies between L126 and Y133, a region within the interconnector domain of PCNA that is known to be a major binding site for many of PCNA's interacting proteins. We hypothesized that therapeutic agents targeting protein-protein interactions mediated through this region may confer differential toxicity to normal and malignant cells. To test this hypothesis, we designed a cell permeable peptide containing the PCNA L126-Y133 sequence. Here, we report that this peptide selectively kills human neuroblastoma cells, especially those with MYCN gene amplification, with much less toxicity to non-malignant human cells. Mechanistically, the peptide is able to block PCNA interactions in cancer cells. It interferes with DNA synthesis and homologous recombination-mediated double-stranded DNA break repair, resulting in S-phase arrest, accumulation of DNA damage, and enhanced sensitivity to cisplatin. These results demonstrate conceptually the utility of this peptide for treating neuroblastomas, particularly, the unfavorable MYCN-amplified tumors. PMID:24728180

  6. Neuroblastoma-like schwannoma in a case of schwannomatosis: Report of a rare case.

    PubMed

    Sulhyan, Kalpana R; Deshmukh, Bhakti D; Gosavi, Alka V; Ramteerthakar, Nayan A

    2015-10-01

    Schwannomatosis is a term used to describe patients with multiple nonvestibular schwannomas with no other stigmata of neurofibromatosis type-2 (NF2). Neuroblastoma-like schwannoma is a rare subtype of schwannoma, with histological features resembling a neuroblastoma. This case is probabaly the second case of very uncommon neuroblastoma-like schwannoma, in a patient of schwannomatosis. PMID:26715928

  7. Neuroblastoma-like schwannoma in a case of schwannomatosis: Report of a rare case

    PubMed Central

    Sulhyan, Kalpana R; Deshmukh, Bhakti D; Gosavi, Alka V; Ramteerthakar, Nayan A

    2015-01-01

    Schwannomatosis is a term used to describe patients with multiple nonvestibular schwannomas with no other stigmata of neurofibromatosis type-2 (NF2). Neuroblastoma-like schwannoma is a rare subtype of schwannoma, with histological features resembling a neuroblastoma. This case is probabaly the second case of very uncommon neuroblastoma-like schwannoma, in a patient of schwannomatosis. PMID:26715928

  8. In vitro synthesis and purification of PhIP-deoxyguanosine and PhIP-DNA oligomer covalent complexes

    SciTech Connect

    Freeman, J.

    1994-12-01

    2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a heterocyclic amine compound formed when meats are cooked at high temperatures. PhIP damages DNA by forming covalent complexes with DNA carcinogen. In an effort to understand how the binding of PhIP to DNA may cause cancer, it is important to characterize the structures of PhIP-damaged DNA molecules. Our HPLC data support fluorescence and {sup 32}P Post-labeling studies which indicate the formation of several species of 2{prime}deoxyguanosine-(dG) or oligodeoxynucleotide-PhIP adducts. The reaction of PhIP with dG resulted in a reddish precipitate that was likely the major adduct, N-(deoxyguanosin-8-yl)-PhIP (dG-C8-PhIP) adduct, with a more polar adduct fraction remaining in the supernatant. Reversed-phase HPLC analysis of the adducts in the supernatant revealed the existence of species of much shorter retention times than the dG-C8-PhIP adduct, confirming that these species are more polar than dG-C8-PhIP. At least four adducts were formed in the reaction of PhIP with DNA oligomer. HPLC analysis of the PhIP-DNA oligomer supernatant after butanol extractions revealed four unresolved peaks which spectra had maximum wavelengths between 340 and 360 nm. Though adduct peaks were not completely resolved, there was {approximately}3 minutes interval between the DNA oligomer peak and the adduct peaks. Furthermore, fluorescence emission data of the DNA oligomer-PhIP adduct solution show heterogeneous binding. The more polar PhIP adducts were fraction-collected and their structures will be solved by nuclear magnetic resonance or x-ray crystallography.

  9. Advances in Risk Classification and Treatment Strategies for Neuroblastoma.

    PubMed

    Pinto, Navin R; Applebaum, Mark A; Volchenboum, Samuel L; Matthay, Katherine K; London, Wendy B; Ambros, Peter F; Nakagawara, Akira; Berthold, Frank; Schleiermacher, Gudrun; Park, Julie R; Valteau-Couanet, Dominique; Pearson, Andrew D J; Cohn, Susan L

    2015-09-20

    Risk-based treatment approaches for neuroblastoma have been ongoing for decades. However, the criteria used to define risk in various institutional and cooperative groups were disparate, limiting the ability to compare clinical trial results. To mitigate this problem and enhance collaborative research, homogenous pretreatment patient cohorts have been defined by the International Neuroblastoma Risk Group classification system. During the past 30 years, increasingly intensive, multimodality approaches have been developed to treat patients who are classified as high risk, whereas patients with low- or intermediate-risk neuroblastoma have received reduced therapy. This treatment approach has resulted in improved outcome, although survival for high-risk patients remains poor, emphasizing the need for more effective treatments. Increased knowledge regarding the biology and genetic basis of neuroblastoma has led to the discovery of druggable targets and promising, new therapeutic approaches. Collaborative efforts of institutions and international cooperative groups have led to advances in our understanding of neuroblastoma biology, refinements in risk classification, and stratified treatment strategies, resulting in improved outcome. International collaboration will be even more critical when evaluating therapies designed to treat small cohorts of patients with rare actionable mutations. PMID:26304901

  10. Aberrant methylation of candidate tumor suppressor genes in neuroblastoma.

    PubMed

    Hoebeeck, Jasmien; Michels, Evi; Pattyn, Filip; Combaret, Valérie; Vermeulen, Joëlle; Yigit, Nurten; Hoyoux, Claire; Laureys, Geneviève; De Paepe, Anne; Speleman, Frank; Vandesompele, Jo

    2009-01-18

    CpG island hypermethylation has been recognized as an alternative mechanism for tumor suppressor gene inactivation. In this study, we performed methylation-specific PCR (MSP) to investigate the methylation status of 10 selected tumor suppressor genes in neuroblastoma. Seven of the investigated genes (CD44, RASSF1A, CASP8, PTEN, ZMYND10, CDH1, PRDM2) showed high frequencies (> or =30%) of methylation in 33 neuroblastoma cell lines. In 42 primary neuroblastoma tumors, the frequencies of methylation were 69%, CD44; 71%, RASSF1A; 56%, CASP8; 25%, PTEN; 15%, ZMYND10; 8%, CDH1; and 0%, PRDM2. Furthermore, CASP8 and CDH1 hypermethylation was significantly associated with poor event-free survival. Meta-analysis of 115 neuroblastoma tumors demonstrated a significant correlation between CASP8 methylation and MYCN amplification. In addition, there was a correlation between ZMYND10 methylation and MYCN amplification. The MSP data, together with optimized mRNA re-expression experiments (in terms of concentration and time of treatment and use of proper reference genes) further strengthen the notion that epigenetic alterations could play a significant role in NB oncogenesis. This study thus warrants the need for a global profiling of gene promoter hypermethylation to identify genome-wide aberrantly methylated genes in order to further understand neuroblastoma pathogenesis and to identify prognostic methylation markers. PMID:18819746

  11. Stromal heparan sulfate differentiates neuroblasts to suppress neuroblastoma growth

    PubMed Central

    Knelson, Erik H.; Gaviglio, Angela L.; Nee, Jasmine C.; Starr, Mark D.; Nixon, Andrew B.; Marcus, Stephen G.; Blobe, Gerard C.

    2014-01-01

    Neuroblastoma prognosis is dependent on both the differentiation state and stromal content of the tumor. Neuroblastoma tumor stroma is thought to suppress neuroblast growth via release of soluble differentiating factors. Here, we identified critical growth-limiting components of the differentiating stroma secretome and designed a potential therapeutic strategy based on their central mechanism of action. We demonstrated that expression of heparan sulfate proteoglycans (HSPGs), including TβRIII, GPC1, GPC3, SDC3, and SDC4, is low in neuroblasts and high in the Schwannian stroma. Evaluation of neuroblastoma patient microarray data revealed an association between TGFBR3, GPC1, and SDC3 expression and improved prognosis. Treatment of neuroblastoma cell lines with soluble HSPGs promoted neuroblast differentiation via FGFR1 and ERK phosphorylation, leading to upregulation of the transcription factor inhibitor of DNA binding 1 (ID1). HSPGs also enhanced FGF2-dependent differentiation, and the anticoagulant heparin had a similar effect, leading to decreased neuroblast proliferation. Dissection of individual sulfation sites identified 2-O, 3-O-desulfated heparin (ODSH) as a differentiating agent, and treatment of orthotopic xenograft models with ODSH suppressed tumor growth and metastasis without anticoagulation. These studies support heparan sulfate signaling intermediates as prognostic and therapeutic neuroblastoma biomarkers and demonstrate that tumor stroma biology can inform the design of targeted molecular therapeutics. PMID:24937430

  12. Development and characterization of a human orthotopic neuroblastoma xenograft

    PubMed Central

    Stewart, Elizabeth; Shelat, Anang; Bradley, Cori; Chen, Xiang; Federico, Sara; Thiagarajan, Suresh; Shirinifard, Abbas; Bahrami, Armita; Pappo, Alberto; Qu, Chunxu; Finkelstein, David; Sablauer, Andras; Dyer, Michael A.

    2016-01-01

    Neuroblastoma is a pediatric cancer of the developing sympathoadrenal lineage. The tumors are known to develop from the adrenal gland or paraspinal ganglia and have molecular and cellular features of sympathetic neurons such as dense core vesicles and catecholamine production. Here we present the detailed molecular, cellular, genetic and epigenetic characterization of an orthotopic xenograft derived from a high-risk stage 4 neuroblastoma patient. Overall, the xenografted tumor retained the high risk features of the primary tumor and showed aggressive growth and metastasis in the mouse. Also, the genome was preserved with no additional copy number variations, structural variations or aneuploidy. There were 13 missense mutations identified in the xenograft that were not present in the patient’s primary tumor and there were no new nonsense mutations. None of the missense mutations acquired in the xenograft were in known cancer genes. We also demonstrate the feasibility of using the orthotopic neuroblastoma xenograft to test standard of care chemotherapy and molecular targeted therapeutics. Finally, we optimized a new approach to produce primary cultures of the neuroblastoma xenografts for high-throughput drug screening which can be used to test new combinations of therapeutic agents for neuroblastoma. PMID:25863122

  13. Observation of Fano resonances in all-dielectric nanoparticle oligomers.

    PubMed

    Chong, Katie E; Hopkins, Ben; Staude, Isabelle; Miroshnichenko, Andrey E; Dominguez, Jason; Decker, Manuel; Neshev, Dragomir N; Brener, Igal; Kivshar, Yuri S

    2014-05-28

    It is well-known that oligomers made of metallic nanoparticles are able to support sharp Fano resonances originating from the interference of two plasmonic resonant modes with different spectral width. While such plasmonic oligomers suffer from high dissipative losses, a new route for achieving Fano resonances in nanoparticle oligomers has opened up after the recent experimental observations of electric and magnetic resonances in low-loss dielectric nanoparticles. Here, light scattering by all-dielectric oligomers composed of silicon nanoparticles is studied experimentally for the first time. Pronounced Fano resonances are observed for a variety of lithographically-fabricated heptamer nanostructures consisting of a central particle of varying size, encircled by six nanoparticles of constant size. Based on a full collective mode analysis, the origin of the observed Fano resonances is revealed as a result of interference of the optically-induced magnetic dipole mode of the central particle with the collective mode of the nanoparticle structure. This allows for effective tuning of the Fano resonance to a desired spectral position by a controlled size variation of the central particle. Such optically-induced magnetic Fano resonances in all-dielectric oligomers offer new opportunities for sensing and nonlinear applications. PMID:24616191

  14. Imide oligomers endcapped with phenylethynyl phthalic anhydrides and polymers therefrom

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Smith, Jr., Joseph G. (Inventor)

    1996-01-01

    Controlled molecular weight phenylethynyl terminated imide oligomers (PETIs) have been prepared by the cyclodehydration of precursor phenylethynyl terminated amic acid oligomers. Amino terminated amic acid oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and subsequently endcapped with phenylethynyl phthalic anhydride(s) (PEPA). The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N,N-dimethylacetamide under nitrogen at room temperature. The amic acid oligomers are subsequently cyclodehydrated either thermally or chemically to the corresponding imide oligomers. Direct preparation of PETIs from the reaction of dianhydride(s) with an excess of diamine(s) and endcapped with phenylethynyl phthalic anhydride(s) has been performed in m-cresol. Phenylethynyl phthalic anhydrides are synthesized by the palladium catalyzed reaction of phenylacetylene with bromo substituted phthalic anhydrides in triethylamine. These new materials exhibit excellent properties and are potentially useful as adhesives, coatings, films, moldings and composite matrices.

  15. Degradation of a Sodium Acrylate Oligomer by an Arthrobacter sp

    PubMed Central

    Hayashi, Takaya; Mukouyama, Masaharu; Sakano, Kouichi; Tani, Yoshiki

    1993-01-01

    Arthrobacter sp. strain NO-18 was first isolated from soil as a bacterium which could degrade the sodium acrylate oligomer and utilize it as the sole source of carbon. When 0.2% (wt/wt) oligomer was added to the culture medium, the acrylate oligomer was found to be degraded by 70 to 80% in 2 weeks, using gel permeation chromatography. To determine the maximum molecular weight for biodegradation, the degradation test was done with the hexamer, heptamer, and octamer, which were separated from the oligomer mixture by fractional gel permeation chromatography. The hexamer and heptamer were consumed to the extents of 58 and 36%, respectively, in 2 weeks, but the octamer was not degraded. Oligomers with three different terminal groups were synthesized to examine the effect of the different terminal groups on biodegradation, but few differences were found. Arthrobacter sp. NO-18 assimilated acrylic acid, propionic acid, glutaric acid, 2-methylglutaric acid, and 1,3,5-pentanetricarboxylic acid. Degradation of the acrylic unit structure by this strain is discussed. PMID:8517751

  16. Imide Oligomers Endcapped with Phenylethynl Phthalic Anhydrides and Polymers Therefrom

    NASA Technical Reports Server (NTRS)

    Hergenrother, Paul M. (Inventor); Smith, Joseph G., Jr. (Inventor)

    1998-01-01

    Controlled molecular weight phenylethynyl terminated imide oligomers (PETIs) have been prepared by the cyclodehydration of precursor phenylethynyl terminated amic acid oligomers. Amino terminated amic acid oligomers are prepared from the reaction of dianhydride(s) with an excess of diamine(s) and subsequently endcapped with phenylethynyl phthalic anhydride(s) (PEPA). The polymerizations are carried out in polar aprotic solvents such as N-methyl-2-pyrrolidinone or N.N-dimethylacetamide under nitrogen at room temperature. The amic acid oligomers are subsequently cyclodehydrated either thermally or cheznicauy to the corresponding imide oligomers. Direct preparation of PETIs from the reaction of dianhydxide(s) with an excess of diamine(s) and endcapped with phenylethynyl phthalic anhydride(s) has been performed in m-cresol. Phenylethynyl phthalic anhydrides are synthesized by the palladium catalyzed reaction of phenylacetylene with bromo substituted phthalic anhydrides in triethylamine. These new materials exhibit excellent properties and are potentially useful as adhesives, coatings, films, moldings and composite matrices.

  17. PET/CT imaging in neuroblastoma.

    PubMed

    Piccardo, A; Lopci, E; Conte, M; Foppiani, L; Garaventa, A; Cabria, M; Villavecchia, G; Fanti, S; Cistaro, A

    2013-03-01

    123Iodine-metaiodobenzylguanidine (123I-MIBG) scintigraphy is currently the tracer of choice for neuroblastoma (NB). It has high diagnostic accuracy and prognostic value for the assessment of patients after chemotherapy. A positive 123I-MIBG scan is also used for the basis of targeted radionuclide therapy with 131I-MIBG. I-123 MIBG scan however has some limitations which should be taken into account. Moreover the reasons for false negative MIBG results have not been entirely elucidated. Meticulous correlation with radiological examinations and recognition of the normal distribution pattern of 123I-MIBG in children is vital to obtain optimal results. With its technical superiorities, positron emission tomography/computed tomography (PET/CT) can be successfully introduced into the diagnostic workup of NB. Different PET tracers have been offered for imaging in patients with NB, and the efficacy of this modality has been compared with that of 123I-MIBG scan. Our review aims to analyze the present role of PET/CT imaging and radiopharmaceuticals in NB. PMID:23474633

  18. Refractory diarrhea: A paraneoplastic syndrome of neuroblastoma.

    PubMed

    Han, Wei; Wang, Huan-Min

    2015-07-01

    Neuroblastoma (NB) is the most common extracranial solid tumor in children. Diarrheal NB is quite rare and is not easy to diagnose in the early stage. Six cases of diarrheal NB in our hospital treated from 1996 to 2006 were retrospectively analyzed, including characteristics such as electrolyte imbalance, pathologic features, vasoactive intestinal peptide (VIP) immunohistochemical staining results, treatment, and prognosis. All patients were boys with 3-8 loose or watery stools each day and routine fecal tests were normal. Abdominal tumors were identified by B-ultrasound. Drugs were ineffective. Three patients underwent surgery, and the remaining three patients received surgery and chemotherapy. Diarrhea stopped after treatment in five patients. Two patients died due to intractable hypokalemia. The tumor was located in the adrenal gland in four patients, in the upper retroperitoneum in one patient, and in the presacral area in one patient. Pathologic findings were NB and ganglioneuroblastoma. Five patients were at clinical stage I-II, and one was at stage III. Four patients survived (followed-up for 6 mo to 4 years). Immunohistochemical staining for VIP was positive. Refractory diarrhea is a paraneoplastic syndrome of NB and is rare. Patients aged 1-3 years who present with chronic intractable diarrhea should be followed closely. Intractable diarrhea, hypokalemia, and dysplasia are the initial clinical manifestations. Increased VIP is characteristic of this disease. Potassium supplementation plays a vital role in the treatment procedure, especially preoperatively. The prognosis of diarrheal NB is good following appropriate treatment. PMID:26167095

  19. Probing the stability of insulin oligomers using electrospray ionization ion mobility mass spectrometry.

    PubMed

    Boga Raja, Uday Kumar; Injeti, Srilakshmi; Culver, Tiffany; McCabe, Jacob W; Angel, Laurence A

    2015-01-01

    The peptide hormone insulin is central to regulating carbohydrate and fat metabolism in the body by controlling blood sugar levels. Insulin's most active form is the monomer and the extent of insulin oligomerization is related to insulin's activity of controlling blood sugar levels. Electrospray ionization (ESI) of human insulin produced a series of oligomers from the monomer to the undecamer identified using quadrupole ion mobility time-of-flight mass spectrometry. Previous research suggested that only the monomer, dimer and hexamer are native forms of insulin in solution and the range of oligomers observed in the gas-phase are ESI artifacts. Here the properties of three distinct oligomer bands I, II and III, where both the charge state and number of insulin units of the oligomer increase incrementally, were investigated. When Zn(ii) was added to the insulin sample the same oligomers were observed but with 0-6 Zn(ii) ions bound to each of the oligomers. The oligomers of bands I, II and III were characterized by comparing their drift times, collision cross- sections, relative intensities, collision-induced dissociation (CID) patterns and relative breakdown energies. Insulin oligomers of band I dissociated primarily by releasing either the 2+ or 3+ monomer accompanied by an oligomer that conserved the mass, charge and Zn(ii) of the precursor. Insulin oligomers of bands II and III dissociated primarily by releasing the 2+ monomer accompanied by an oligomer which conserved the mass, charge and Zn(ii) of the precursor. Comparison of CID patterns and breakdown energies showed all the oligomers in band II required higher collision energies to dissociate than the oligomers in band I, and the oligomers of band III required higher energies to dissociate than oligomers of band II. These results show that the amount of excess charge on the oligomer in respect to the number of insulin monomers in the oligomer affects their stability. PMID:26764306

  20. A Hybrid Robotic Control System Using Neuroblastoma Cultures

    NASA Astrophysics Data System (ADS)

    Ferrández, J. M.; Lorente, V.; Cuadra, J. M.; Delapaz, F.; Álvarez-Sánchez, José Ramón; Fernández, E.

    The main objective of this work is to analyze the computing capabilities of human neuroblastoma cultured cells and to define connection schemes for controlling a robot behavior. Multielectrode Array (MEA) setups have been designed for direct culturing neural cells over silicon or glass substrates, providing the capability to stimulate and record simultaneously populations of neural cells. This paper describes the process of growing human neuroblastoma cells over MEA substrates and tries to modulate the natural physiologic responses of these cells by tetanic stimulation of the culture. We show that the large neuroblastoma networks developed in cultured MEAs are capable of learning: establishing numerous and dynamic connections, with modifiability induced by external stimuli and we propose an hybrid system for controlling a robot to avoid obstacles.

  1. I-131 metaiodobenzylguanidine: diagnostic use in neuroblastoma patients in relapse

    SciTech Connect

    Heyman, S.; Evans, A.E.; D'Angio, G.J.

    1988-01-01

    Metaiodobenzylguanidine (MIBG) has been used for the detection and treatment of neuroectodermal tumors, including neuroblastoma. We report our experience with /sup 131/I-MIBG used diagnostically in neuroblastoma patients with relapse. Thirty-eight studies were performed in 26 patients. There were 24 children (range 3 months-14 years) and two adults. While the study was found to be both sensitive and specific for the presence of disease, there are instances of discordance. False-negative studies were found with a markedly anaplastic tumor and with two mature ganglioneuromas. A bone lesion was negative with /sup 131/I-MIBG, but positive on bone scan. A biopsy confirmed the presence of neuroblastoma. Caution should be exercised when scanning pretreated patients, and perhaps with newly diagnosed patients as well.

  2. Serum polysialylated neural cell adhesion molecule in childhood neuroblastoma.

    PubMed Central

    Glüer, S.; Schelp, C.; Madry, N.; von Schweinitz, D.; Eckhardt, M.; Gerardy-Schahn, R.

    1998-01-01

    Neuroblastoma cells express the polysialylated form of the neural cell adhesion molecule (NCAM), which normally becomes restricted to a few neural tissues after embryogenesis. In this study, we investigated serum levels of polysialylated NCAM in 14 children with different grades and stages of neuroblastoma using an immunoluminescence assay, and compared the results to 269 healthy control subjects. Simultaneously, the polysialylated NCAM content of the tumours was determined by immunohistochemistry. Serum levels were dramatically elevated (more than sixfold) in children with advanced stages and fatal courses of disease, whereas children with differentiated tumour types and limited disease had low or normal levels. Serum concentrations correlated with the polysialylated NCAM content of the tumours, and they decreased during successful therapy. We therefore suggest polysialylated NCAM to be a useful marker monitoring childhood neuroblastoma. Images Figure 2 Figure 3 PMID:9662259

  3. Bilateral Synchronous Ectopic Ethmoid Sinus Olfactory Neuroblastoma: A Case Report.

    PubMed

    Leon-Soriano, Elena; Alfonso, Carolina; Yebenes, Laura; Garcia-Polo, Julio; Lassaletta, Luis; Gavilan, Javier

    2016-01-01

    BACKGROUND Olfactory neuroblastoma (ONB), also known as esthesioneuroblastoma, is a rare malignant head and neck cancer thought to originate from the olfactory epithelium. It typically invades contiguous structures at presentation. We report a very rare case of multifocal and ectopic ONB. CASE REPORT A 41-year-old man presented with left nasal obstruction and occasional left epistaxis associated with headache. Endoscopic examination of the nasal cavities and computed tomography suggested bilateral polypoid masses. Histopathological diagnosis after endoscopic resection established bilateral olfactory neuroblastoma of the ethmoid sinuses. The patient received postoperative radiotherapy. He remains free of disease 4 years after treatment. CONCLUSIONS To the best of our knowledge this is the second documented case of multifocal ectopic olfactory neuroblastoma. Clinicians should consider ONB in the differential diagnosis of bilateral synchronous nasal and paranasal masses to avoid delayed diagnosis. Endoscopic resection of ONB could be an option in selected cases. PMID:27097989

  4. Activated ALK Collaborates with MYCN in Neuroblastoma Pathogenesis

    PubMed Central

    Zhu, Shizhen; Lee, Jeong-Soo; Guo, Feng; Shin, Jimann; Perez-Atayde, Antonio R.; Kutok, Jeffery L.; Rodig, Scott J.; Neuberg, Donna S.; Helman, Daniel; Feng, Hui; Stewart, Rodney A.; Wang, Wenchao; George, Rani E.; Kanki, John P.; Look, A. Thomas

    2012-01-01

    SUMMARY Amplification of the MYCN oncogene in childhood neuroblastoma is often accompanied by mutational activation of ALK (anaplastic lymphoma kinase), suggesting their pathogenic cooperation. We generated a transgenic zebrafish model of neuroblastoma in which MYCN-induced tumors arise from a subpopulation of neuroblasts that migrate into the adrenal medulla analogue following organogenesis. Coexpression of activated ALK with MYCN in this model triples the disease penetrance and markedly accelerates tumor onset. MYCN overexpression induces adrenal sympathetic neuroblast hyperplasia, blocks chromaffin cell differentiation, and ultimately triggers a developmentally-timed apoptotic response in the hyperplastic sympathoadrenal cells. Coexpression of activated ALK with MYCN provides prosurvival signals that block this apoptotic response and allow continued expansion and oncogenic transformation of hyperplastic neuroblasts, thus promoting progression to neuroblastoma. PMID:22439933

  5. α-Synuclein Oligomers Impair Neuronal Microtubule-Kinesin Interplay*

    PubMed Central

    Prots, Iryna; Veber, Vanesa; Brey, Stefanie; Campioni, Silvia; Buder, Katrin; Riek, Roland; Böhm, Konrad J.; Winner, Beate

    2013-01-01

    Early α-synuclein (α-Syn)-induced alterations are neurite pathologies resulting in Lewy neurites. α-Syn oligomers are a toxic species in synucleinopathies and are suspected to cause neuritic pathology. To investigate how α-Syn oligomers may be linked to aberrant neurite pathology, we modeled different stages of α-Syn aggregation in vitro and investigated the interplay of α-Syn aggregates with proteins involved in axonal transport. The interaction of wild type α-Syn (WTS) and α-Syn variants (E57K, A30P, and aSyn(30–110)) with kinesin, tubulin, and the microtubule (MT)-associated proteins, MAP2 and Tau, is stronger for multimers than for monomers. WTS seeds but not α-Syn oligomers significantly and dose-dependently reduced Tau-promoted MT assembly in vitro. In contrast, MT gliding velocity across kinesin-coated surfaces was significantly decreased in the presence of α-Syn oligomers but not WTS seeds or fibrils (aSyn(30–110) multimers). In a human dopaminergic neuronal cell line, mild overexpression of the oligomerizing E57K α-Syn variant significantly impaired neurite network morphology without causing profound cell death. In accordance with these findings, MT stability, neuritic kinesin, and neuritic kinesin-dependent cargoes were significantly reduced by the presence of α-Syn oligomers. In summary, different α-Syn species act divergently on the axonal transport machinery. These findings provide new insights into α-Syn oligomer-driven neuritic pathology as one of the earliest events in synucleinopathies. PMID:23744071

  6. Acetaminophen Induces Human Neuroblastoma Cell Death through NFKB Activation

    PubMed Central

    Posadas, Inmaculada; Santos, Pablo; Ceña, Valentín

    2012-01-01

    Neuroblastoma resistance to apoptosis may contribute to the aggressive behavior of this tumor. Therefore, it would be relevant to activate endogenous cellular death mechanisms as a way to improve neuroblastoma therapy. We used the neuroblastoma SH-SY5Y cell line as a model to study the mechanisms involved in acetaminophen (AAP)-mediated toxicity by measuring CYP2E1 enzymatic activity, NFkB p65 subunit activation and translocation to the nucleus, Bax accumulation into the mitochondria, cytochrome c release and caspase activation. AAP activates the intrinsic death pathway in the SH-SY5Y human neuroblastoma cell line. AAP metabolism is partially responsible for this activation, because blockade of the cytochrome CYP2E1 significantly reduced but did not totally prevent, AAP-induced SH-SY5Y cell death. AAP also induced NFkB p65 activation by phosphorylation and its translocation to the nucleus, where NFkB p65 increased IL-1β production. This increase contributed to neuroblastoma cell death through a mechanism involving Bax accumulation into the mitochondria, cytochrome c release and caspase3 activation. Blockade of NFkB translocation to the nucleus by the peptide SN50 prevented AAP-mediated cell death and IL-1β production. Moreover, overexpression of the antiapoptotic protein Bcl-xL did not decrease AAP-mediated IL-1β production, but prevented both AAP and IL-1β-mediated cell death. We also confirmed the AAP toxic actions on SK-N-MC neuroepithelioma and U87MG glioblastoma cell lines. The results presented here suggest that AAP activates the intrinsic death pathway in neuroblastoma cells through a mechanism involving NFkB and IL-1β. PMID:23166834

  7. No evidence for involvement of SDHD in neuroblastoma pathogenesis

    PubMed Central

    De Preter, Katleen; Vandesompele, Jo; Hoebeeck, Jasmien; Vandenbroecke, Caroline; Smet, Jöel; Nuyts, Annick; Laureys, Geneviève; Combaret, Valérie; Van Roy, Nadine; Roels, Frank; Van Coster, Rudy; Praet, Marleen; De Paepe, Anne; Speleman, Frank

    2004-01-01

    Background Deletions in the long arm of chromosome 11 are observed in a subgroup of advanced stage neuroblastomas with poor outcome. The deleted region harbours the tumour suppressor gene SDHD that is frequently mutated in paraganglioma and pheochromocytoma, which are, like neuroblastoma, tumours originating from the neural crest. In this study, we sought for evidence for involvement of SDHD in neuroblastoma. Methods SDHD was investigated on the genome, transcriptome and proteome level using mutation screening, methylation specific PCR, real-time quantitative PCR based homozygous deletion screening and mRNA expression profiling, immunoblotting, functional protein analysis and ultrastructural imaging of the mitochondria. Results Analysis at the genomic level of 67 tumour samples and 37 cell lines revealed at least 2 bona-fide mutations in cell lines without allelic loss at 11q23: a 4bp-deletion causing skip of exon 3 resulting in a premature stop codon in cell line N206, and a Y93C mutation in cell line NMB located in a region affected by germline SDHD mutations causing hereditary paraganglioma. No evidence for hypermethylation of the SDHD promotor region was observed, nor could we detect homozygous deletions. Interestingly, SDHD mRNA expression was significantly reduced in SDHD mutated cell lines and cell lines with 11q allelic loss as compared to both cell lines without 11q allelic loss and normal foetal neuroblast cells. However, protein analyses and assessment of mitochondrial morphology presently do not provide clues as to the possible effect of reduced SDHD expression on the neuroblastoma tumour phenotype. Conclusions Our study provides no indications for 2-hit involvement of SDHD in the pathogenesis of neuroblastoma. Also, although a haplo-insufficient mechanism for SDHD involvement in advanced stage neuroblastoma could be considered, the present data do not provide consistent evidence for this hypothesis. PMID:15331017

  8. Oligomer-assisted synthesis of chiral polyaniline nanofibers.

    PubMed

    Li, Wenguang; Wang, Hsing-Lin

    2004-03-01

    We report here a novel approach to synthesize chiral PANI nanofibers in an aqueous solution. This new approach requires the following conditions: (1) Polymerization was carried out in concentrated camphor sulfonic acid solutions. (2) Aniline oligomers were used to accelerate the polymerization reaction. (3) Ammonium persulfate (oxidant) was added incrementally to the aniline solution. The high anisotropy factor of these PANI nanofibers is likely due to the "autocatalytic effect" resulting from lower oxidation potentials of aniline oligomers. Our chemical synthesis of the chiral PANI nanofibers is enantioselective and, under the optimized conditions, has an anisotropy factor (g = Deltaepsilon/epsilon) of 2.3 x 10-2. PMID:14982411

  9. Tau oligomers as potential targets for early diagnosis of tauopathy.

    PubMed

    Sahara, Naruhiko; Ren, Yan; Ward, Sarah; Binder, Lester I; Suhara, Tetsuya; Higuchi, Makoto

    2014-01-01

    The discovery of tau mutations in frontotemporal dementia has been a key event in neurodegenerative disease research. The rTg4510 mouse line expressing human tau with P301L FTDP-17-tau mutation has been established to understand the role of tau in neurodegeneration. Our histological analyses with tau antibodies and fluorescent tau ligands on rTg4510 mice revealed that tau oligomer formation was distinct from tangle formation. While in vivo imaging of mature tangles is now available, imaging biomarkers for tau oligomers would be useful for clarifying their roles in neurotoxicity and for diagnosing early-stage tau pathology. PMID:24595194

  10. Femtosecond spectroscopy of a thiophene oligomer with a photoswitch

    NASA Astrophysics Data System (ADS)

    Tamai, N.; Saika, T.

    1996-04-01

    Femtosecond transient absorption spectroscopy was applied to analyze the mechanism of optical switch of an endo-capped thiophene oligomer with a diarylethene structure as a new class of multimode chemical transducers. The rate of the optical switch of the proconductivity was estimated to be 1.1 ps, corresponding to the formation time of the closed-ring form of thiophene oligomer. From the direct observation of the precursor of closed-ring form, the mechanism of photochromic ring-closure reaction was discussed.

  11. Probenecid Sensitizes Neuroblastoma Cancer Stem Cells to Cisplatin.

    PubMed

    Campos-Arroyo, Denise; Maldonado, Vilma; Bahena, Ivan; Quintanar, Valeria; Patiño, Nelly; Carlos Martinez-Lazcano, Juan; Melendez-Zajgla, Jorge

    2016-03-15

    We used both in vitro cultures of neuroblastoma cell lines and nude-mice xenotransplants to explore the effects of co-administration of cisplatin and probenecid. Probenecid sensitized neuroblastoma cells, including tumor cells with stem features, to the effects of cisplatin, both in vitro and in vivo. This effect was mediated by an increase in the apoptotic cell death and a concomitant decrease in cell proliferation. This effect is accompanied by modulation of the mRNA and protein of the drug efflux transporters MDR1, MRP2, and BCRP. The co-administration of probenecid with cisplatin should be explored as a possible therapeutic strategy. PMID:26963048

  12. A Technique for Excision of Abdominal and Pelvic Neuroblastomas

    PubMed Central

    Kiely, Edward

    2007-01-01

    INTRODUCTION As neuroblastomas usually envelope major vessels, excision poses a significant technical problem. PATIENTS AND METHODS Over a 22-year period, 234 infants and children have undergone attempted surgical excision of abdominal or pelvic neuroblastomas using a consistent surgical approach. This entails a systematic dissection of the involved vessels prior to removal of the tumour. RESULTS Macroscopically complete or near complete tumour clearance was achieved in 89% of cases. Three aortic injuries occurred which required repair. CONCLUSION The described technique is safe and reproducible and allows tumour clearance in the majority offfected children. PMID:17535608

  13. Biophysical characterization data on Aβ soluble oligomers produced through a method enabling prolonged oligomer stability and biological buffer conditions

    PubMed Central

    Crisostomo, Amanda C.; Dang, Loan; Digambaranath, Jyothi L.; Klaver, Andrea C.; Loeffler, David A.; Payne, Jeremiah J.; Smith, Lynnae M.; Yokom, Adam L.; Finke, John M.

    2015-01-01

    The data here consists of time-dependent experimental parameters from chemical and biophysical methods used to characterize Aβ monomeric reactants as well as soluble oligomer and amyloid fibril products from a slow (3–4 week) assembly reaction under biologically-relevant solvent conditions. The data of this reaction are both of a qualitative and quantitative nature, including gel images from chemical cross-linking and Western blots, fractional solubility, thioflavin T binding, size exclusion chromatograms, transmission electron microscopy images, circular dichroism spectra, and fluorescence resonance energy transfer efficiencies of donor–acceptor pair labels in the Aβ chain. This data enables future efforts to produce the initial monomer and eventual soluble oligomer and amyloid fibril states by providing reference benchmarks of these states pertaining to physical properties (solubility), ligand-binding (thioflavin T binding), mesoscopic structure (electron microscopy, size exclusion chromatography, cross-linking products, SDS and native gels) and molecular structure (circular dichroism, FRET donor-acceptor distance). Aβ1-40 soluble oligomers are produced that are suitable for biophysical studies requiring sufficient transient stability to exist in their “native” conformation in biological phosphate-saline buffers for extended periods of time. The production involves an initial preparation of highly monomeric Aβ in a phosphate saline buffer that transitions to fibrils and oligomers through time incubation alone, without added detergents or non-aqueous chemicals. This criteria ensures that the only difference between initial monomeric Aβ reactant and subsequent Aβ oligomer products is their degree of peptide assembly. A number of chemical and biophysical methods were used to characterize the monomeric reactants and soluble oligomer and amyloid fibril products, including chemical cross-linking, Western blots, fraction solubility, thioflvain T binding

  14. Dehydroepiandrosterone protects male and female hippocampal neurons and neuroblastoma cells from glucose deprivation.

    PubMed

    Vieira-Marques, Claudia; Arbo, Bruno Dutra; Ruiz-Palmero, Isabel; Ortiz-Rodriguez, Ana; Ghorbanpoor, Samar; Kucharski, Luiz Carlos; Arevalo, Maria A; Garcia-Segura, Luis Miguel; Ribeiro, Maria Flávia M

    2016-08-01

    Dehydroepiandrosterone (DHEA) modulates neurogenesis, neuronal function, neuronal survival and metabolism, enhancing mitochondrial oxidative capacity. Glucose deprivation and hypometabolism have been implicated in the mechanisms that mediate neuronal damage in neurological disorders, and some studies have shown that these mechanisms are sexually dimorphic. It was also demonstrated that DHEA is able to attenuate the hypometabolism that is related to some neurodegenerative diseases, eliciting neuroprotective effects in different experimental models of neurodegeneration. The aim of this study was to evaluate the effect of DHEA on the viability of male and female hippocampal neurons and SH-SY5Y neuroblastoma cells exposed to glucose deprivation. It was observed that after 12h of pre-treatment, DHEA was able to protect SH-SY5Y cells from glucose deprivation for 6h (DHEA 10(-12), 10(-8) and 10(-6)M) and 8h (DHEA 10(-8)M). In contrast, DHEA was not neuroprotective against glucose deprivation for 12 or 24h. DHEA (10(-8)M) also protected SH-SY5Y cells when added together or even 1h after the beginning of glucose deprivation (6h). Furthermore, DHEA (10(-8)M) also protected primary neurons from both sexes against glucose deprivation. In summary, our findings indicate that DHEA is neuroprotective against glucose deprivation in human neuroblastoma cells and in male and female mouse hippocampal neurons. These results suggest that DHEA could be a promising candidate to be used in clinical studies aiming to reduce neuronal damage in people from both sexes. PMID:27174000

  15. Energy metabolism in neuroblastoma and Wilms tumor

    PubMed Central

    Aminzadeh, Sepideh; Vidali, Silvia; Sperl, Wolfgang; Feichtinger, René G.

    2015-01-01

    To support high proliferation, the majority of cancer cells undergo fundamental metabolic changes such as increasing their glucose uptake and shifting to glycolysis for ATP production at the expense of far more efficient mitochondrial energy production by oxidative phosphorylation (OXPHOS), which at first glance is a paradox. This phenomenon is known as the Warburg effect. However, enhanced glycolysis is necessary to provide building blocks for anabolic growth. Apart from the generation of ATP, intermediates of glycolysis serve as precursors for a variety of biosynthetic pathways essential for cell proliferation. In the last 10-15 years the field of tumor metabolism has experienced an enormous boom in interest. It is now well established that tumor suppressor genes and oncogenes often play a central role in the regulation of cellular metabolism. Therefore, they significantly contribute to the manifestation of the Warburg effect. While much attention has focused on adult solid tumors, so far there has been comparatively little effort directed at elucidation of the mechanism responsible for the Warburg effect in childhood cancers. In this review we focus on metabolic pathways in neuroblastoma (NB) and Wilms tumor (WT), the two most frequent solid tumors in children. Both tumor types show alterations of the OXPHOS system and glycolytic features. Chromosomal alterations and activation of oncogenes like MYC or inactivation of tumor suppressor genes like TP53 can in part explain the changes of energy metabolism in these cancers. The strict dependence of cancer cells on glucose metabolism is a fairly common feature among otherwise biologically diverse types of cancer. Therefore, inhibition of glycolysis or starvation of cancer cells through glucose deprivation via a high-fat low-carbohydrate diet may be a promising avenue for future adjuvant therapeutic strategies. PMID:26835356

  16. Oligomer Molecules for Efficient Organic Photovoltaics.

    PubMed

    Lin, Yuze; Zhan, Xiaowei

    2016-02-16

    Solar cells, a renewable, clean energy technology that efficiently converts sunlight into electricity, are a promising long-term solution for energy and environmental problems caused by a mass of production and the use of fossil fuels. Solution-processed organic solar cells (OSCs) have attracted much attention in the past few years because of several advantages, including easy fabrication, low cost, lightweight, and flexibility. Now, OSCs exhibit power conversion efficiencies (PCEs) of over 10%. In the early stage of OSCs, vapor-deposited organic dye materials were first used in bilayer heterojunction devices in the 1980s, and then, solution-processed polymers were introduced in bulk heterojunction (BHJ) devices. Relative to polymers, vapor-deposited small molecules offer potential advantages, such as a defined molecular structure, definite molecular weight, easy purification, mass-scale production, and good batch-to-batch reproducibility. However, the limited solubility and high crystallinity of vapor-deposited small molecules are unfavorable for use in solution-processed BHJ OSCs. Conversely, polymers have good solution-processing and film-forming properties and are easily processed into flexible devices, whereas their polydispersity of molecular weights and difficulty in purification results in batch to batch variation, which may hamper performance reproducibility and commercialization. Oligomer molecules (OMs) are monodisperse big molecules with intermediate molecular weights (generally in the thousands), and their sizes are between those of small molecules (generally with molecular weights <1000) and polymers (generally with molecular weights >10000). OMs not only overcome shortcomings of both vapor-deposited small molecules and solution-processed polymers, but also combine their advantages, such as defined molecular structure, definite molecular weight, easy purification, mass-scale production, good batch-to-batch reproducibility, good solution processability

  17. Structure and topochemistry of azodioxide oligomers in solid state

    NASA Astrophysics Data System (ADS)

    Bibulić, Petar; Rončević, Igor; Varga, Katarina; Mihalić, Zlatko; Vančik, Hrvoj

    2016-01-01

    The structure of oligomers constructed from 1,4-dinitrosobenzene was studied computationally by DFT methods for shorter oligomers, and by the FMO approach for longer ones. It was demonstrated that the oligomers have helical structure. Formation of 1,4-dinitrosobenzene azodioxides from the corresponding nitroso monomers in solid state was examined by studying the kinetics of their oligomerization under cryogenic conditions. Dissociation of azodioxide bonds to nitroso groups was induced either by UV irradiation at cryogenic temperatures or by sublimation followed by cryogenic deposition. While warming the monomers prepared by UV photodissociation to 150 K gave E-polymers, oligomerization or polymerization of monomers prepared by cryogenic vapor deposition was less pronounced, giving Z-forms. Above 150 K, Z-dimers or short oligomers isomerized, probably by the dissociation-dimerization mechanism, to more stable E-forms. Fast formation of azodioxide bonds and the high stability of corresponding polymers can be ascribed to the strong topochemical effect in the solid state.

  18. Small Glycosylated Lignin Oligomers Are Stored in Arabidopsis Leaf Vacuoles

    PubMed Central

    Dima, Oana; Morreel, Kris; Vanholme, Bartel; Kim, Hoon; Ralph, John; Boerjan, Wout

    2015-01-01

    Lignin is an aromatic polymer derived from the combinatorial coupling of monolignol radicals in the cell wall. Recently, various glycosylated lignin oligomers have been revealed in Arabidopsis thaliana. Given that monolignol oxidation and monolignol radical coupling are known to occur in the apoplast, and glycosylation in the cytoplasm, it raises questions about the subcellular localization of glycosylated lignin oligomer biosynthesis and their storage. By metabolite profiling of Arabidopsis leaf vacuoles, we show that the leaf vacuole stores a large number of these small glycosylated lignin oligomers. Their structural variety and the incorporation of alternative monomers, as observed in Arabidopsis mutants with altered monolignol biosynthesis, indicate that they are all formed by combinatorial radical coupling. In contrast to the common believe that combinatorial coupling is restricted to the apoplast, we hypothesized that the aglycones of these compounds are made within the cell. To investigate this, leaf protoplast cultures were cofed with 13C6-labeled coniferyl alcohol and a 13C4-labeled dimer of coniferyl alcohol. Metabolite profiling of the cofed protoplasts provided strong support for the occurrence of intracellular monolignol coupling. We therefore propose a metabolic pathway involving intracellular combinatorial coupling of monolignol radicals, followed by oligomer glycosylation and vacuolar import, which shares characteristics with both lignin and lignan biosynthesis. PMID:25700483

  19. Ferroelectric and dielectric properties of electroactive oligomers and nanocomposites

    NASA Astrophysics Data System (ADS)

    Kraemer, Kristin L.

    Polyvinylidene fluoride (PVDF) and its copolymers have been well established as ferroelectric polymers. The dielectric and ferroelectric properties for vinylidene fluoride (VDF) oligomer thin films were investigated. By synthesizing oligomers instead of long polymer chains, films with higher crystalinity can be formed and the locations of oligomers can be controlled for applications such as molecular electronics. Evidence of ferroelectricity was observed in oligomer thin films evaporated onto room temperature substrates and by Langmuir-Blodgett (LB) deposition. Voltage and frequency dependence of the capacitance was measured. Oligomers functionalized with phosphonic acid formed self-assembled monolayers (SAM) on aluminum and mica substrates. Film thickness was measured by ellipsometry and atomic force microscopy (AFM). The time dependence on film growth was measured for SAMs on mica substrates by AFM. The islands had already formed by 1 minute, and by 1 hour film was continuous. Additionally, studies were performed on composite dielectric systems with the goal of fabricating high energy density dielectrics containing nanoparticles with an organic shell. The first two types of samples had barium titante nanoparticles coated with functionalized alkanes or VDF oligomers. The first sample type consisted of coated nanoparticles embedded in a PVDF copolymer or terpolymer spin-coated film. At low particle concentrations, the matrix properties dominated the electrical measurements while at high concentrations, the samples were electrically fragile. The second sample type consisted of alternating layers of LB terpolymer and LB nanoparticles. These samples allowed for high particle concentrations while maintaining the high breakdown strength of the polymer layers. The final type of sample was titanium dioxide nanoparticles formed by cluster deposition and coated with an evaporated paraffin or VDF oligomer. These samples tended to have low breakdown strengths and poor

  20. Montmorillonite Clay-Catalyzed Synthesis of RNA Oligomers

    NASA Astrophysics Data System (ADS)

    Ferris, J. P.; Miyakawa, S.; Huang, W.; Joshi, P.

    2005-12-01

    It is proposed that catalysis had a central role in the origins of life. This will be illustrated using the montmorillonite clay-catalyzed synthesis of oligomers of RNA from activated monomers, (Ferris and Ertem, 1993) a possible step in the origin of the RNA world (Ferris, 2005). Structural analysis of oligomers formed in the reaction of the activated monomer of 5'-AMP with that of 5'-CMP demonstrated that the oligomers formed were not produced by random synthesis but rather the sequences observed were directed by the montmorillonite catalyst (Miyakawa and Ferris, 2003). RNA oligomers containing up to 40 mers have been synthesized in reactions performed in water at 25 oC in the presence of montmorillonite (Huang and Ferris, 2003). Analysis of the structure elements in these oligomers from the 7 to 39 mers showed that they did not vary. Reaction of D, L-mixtures of the activated monomers of A and U resulted in the formation of greater amounts of the homochiral amounts of dimers and trimers of A than would be expected if there was no selectivity in the reaction. A limited number of the dimers and trimers of U were also formed but here the selectivity was for the formation of an excess of heterochiral products (Joshi et al., 2000). A postulate that explains why homochiral trimers of U are not formed and the significance of catalysis in prebiotic synthesis will be discussed. Ferris, J.P. (2005) Origins of life, molecular basis of. In R.A. Meyers, Ed. Encyclopedia of Molecular Cell Biology and Molecular Medicine, 10. Wiley-VCH Verlag, Weinheim, Germany. Ferris, J.P., and Ertem, G. (1993) Montmorillonite catalysis of RNA oligomer formation in aqueous solution. A model for the prebiotic formation of RNA. J. Am. Chem. Soc., 115, 12270-12275. Huang, W., and Ferris, J.P. (2003) Synthesis of 35-40 mers of RNA oligomers from unblocked monomers. A simple approach to the RNA world. Chem. Commun., 1458-1459. Joshi, P.C., Pitsch, S., and Ferris, J.P. (2000) Homochiral selection

  1. Discovery – Ch14.18 Immunotherapy to Treat Neuroblastoma

    Cancer.gov

    Neuroblastoma is rare yet it's the most common cancer affecting infants. Prior to a discovery 20 years in the making, there was little hope for survival in children with advanced stages of the disease. Today, research is leading to a brighter outlook.

  2. Relapsed neuroblastomas show frequent RAS-MAPK pathway mutations

    PubMed Central

    Eleveld, Thomas F.; Oldridge, Derek A.; Bernard, Virginie; Koster, Jan; Daage, Leo Colmet; Diskin, Sharon J.; Schild, Linda; Bentahar, Nadia Bessoltane; Bellini, Angela; Chicard, Mathieu; Lapouble, Eve; Combaret, Valérie; Legoix-Né, Patricia; Michon, Jean; Pugh, Trevor J.; Hart, Lori S.; Rader, JulieAnn; Attiyeh, Edward F.; Wei, Jun S.; Zhang, Shile; Naranjo, Arlene; Gastier-Foster, Julie M.; Hogarty, Michael D.; Asgharzadeh, Shahab; Smith, Malcolm A.; Guidry Auvil, Jaime M.; Watkins, Thomas B. K.; Zwijnenburg, Danny A.; Ebus, Marli E.; van Sluis, Peter; Hakkert, Anne; van Wezel, Esther; van der Schoot, C. Ellen; Westerhout, Ellen M.; Schulte, Johannes H.; Tytgat, Godelieve A.; Dolman, M. Emmy M.; Janoueix-Lerosey, Isabelle; Gerhard, Daniela S.; Caron, Huib N.; Delattre, Olivier; Khan, Javed; Versteeg, Rogier; Schleiermacher, Gudrun; Molenaar, Jan J.; Maris, John M.

    2016-01-01

    The majority of neuroblastoma patients have tumors that initially respond to chemotherapy, but a large proportion of patients will experience therapy-resistant relapses. The molecular basis of this aggressive phenotype is unknown. Whole genome sequencing of 23 paired diagnostic and relapsed neuroblastomas showed clonal evolution from the diagnostic tumor with a median of 29 somatic mutations unique to the relapse sample. Eighteen of the 23 relapse tumors (78%) showed mutations predicted to activate the RAS-MAPK signaling pathway. Seven events were detected only in the relapse tumor while the others showed clonal enrichment. In neuroblastoma cell lines we also detected a high frequency of activating mutations in the RAS-MAPK pathway (11/18, 61%) and these lesions predicted for sensitivity to MEK inhibition in vitro and in vivo. Our findings provide the rationale for genetic characterization of relapse neuroblastoma and show that RAS-MAPK pathway mutations may function as a biomarker for new therapeutic approaches to refractory disease. PMID:26121087

  3. Immunolocalization of neuroblastoma using radiolabeled monoclonal antibody UJ13A

    SciTech Connect

    Goldman, A.; Vivian, G.; Gordon, I.; Pritchard, J.; Kemshead, J.

    1984-08-01

    The monoclonal antibody UJ13A, raised after immunization of mice with human fetal brain, recognized an antigen expressed on human neuroblastoma cell lines and fresh tumors. Antibody was purified and radiolabeled with iodine isotopes using chloramine-T. In preclinical studies, 125I-labeled UJ13A was injected intravenously into nude mice bearing xenografts of human neuroblastoma. Radiolabeled UJ13A uptake by the tumors was four to 23 times greater than that by blood. In control animals, injected with a similar quantity of a monoclonal antibody known not to bind to neuroblastoma cells in vitro (FD44), there was no selective tumor uptake. Nine patients with histologically confirmed neuroblastoma each received 100 to 300 micrograms UJ13A radiolabeled with 1 to 2.8 mCi 123I or 131I. Sixteen positive sites were visible on gamma scans 1 to 7 days after injection: 15 were primary or secondary tumor sites, and one was a false positive; there were two false negatives. In two of the 15 positive sites, tumor had not been demonstrated by other imaging techniques; these were later confirmed as areas of malignant infiltration. No toxicity was encountered.

  4. Subsequent Malignant Neoplasms in Pediatric Patients Initially Diagnosed with Neuroblastoma

    PubMed Central

    Federico, Sara M.; Allewelt, Heather; Spunt, Sheri L.; Hudson, Melissa M.; Wu, Jianrong; Billups, Catherine A.; Jenkins, Jesse; Santana, Victor M.; Furman, Wayne L.; McGregor, Lisa M.

    2014-01-01

    Background Most prior studies evaluating subsequent malignant neoplasms (SMN) in patients with neuroblastoma are restricted to long-term survivors and/or their treatment exposures. This study investigates SMNs in patients diagnosed with neuroblastoma at our institution. Methods Records of 646 patients treated for neuroblastoma at St. Jude Children’s Research Hospital between 1961 and 2005 were reviewed. Data from patients with SMNs were analyzed and the 20-year and 30-year cumulative incidence of SMNs and standardized incidence ratio (SIR) were calculated. Results Twenty-one patients had a SMN. The 20- and 30-year cumulative incidences of a SMN were 2.6% ± 0.7% and 4.6% ± 1.1% respectively. The SIR was 8.3 (95% CI, 5.0–13.0). Five patients developed a SMN within 5 years from diagnosis. The median latency for the development of AML/MDS (n=4), sarcomas (n=7), and carcinomas (n=5) were 3.6 years, 9 years, and 24.2 years respectively. Nine patients died from their SMN, including all with AML/MDS. Conclusions Patients with neuroblastoma have an increased risk of secondary neoplasia. Modification of risk-adapted therapies will likely alter the affected patient population and the incidence of SMNs. Future studies are necessary to link SMNs to treatment exposures and to evaluate the risk of SMNs beyond 30 years from diagnosis. PMID:24633303

  5. 131I-Metaiodobenzylguanidine therapy in children with advanced neuroblastoma.

    PubMed

    DuBois, S G; Matthay, K K

    2013-03-01

    Neuroblastoma is an aggressive childhood cancer, with a propensity for early widespread metastasis. Approximately 90% of tumors accumulate the norepinephrine analogue metaiodobenzylguanidine (MIBG) avidly, allowing the use of radiolabeled MIBG for targeted imaging and radiotherapy. After preclinical studies demonstrated activity of 131I-MIBG in models of neuroblastoma, clinical development of this agent ensued. Early clinical trials of 131I-MIBG in patients with relapsed or refractory neuroblastoma defined the toxicity profile of this agent, with myelosuppression as the main dose-limiting toxicity. Subsequent trials defined the activity of 131I-MIBG, with response rates of 20-40% in patients with relapsed or refractory disease. More recent clinical trials have tested 131I-MIBG in combination with chemotherapy or as a component of myeloablative therapies. Given the documented activity of 131I-MIBG, future studies will need to evaluate the impact of radiation sensitizers on this activity and define the role of this agent in treating patients with newly diagnosed high-risk neuroblastoma. PMID:23474635

  6. Clinical results of proton beam therapy for advanced neuroblastoma

    PubMed Central

    2013-01-01

    Purpose To evaluate the efficacy of proton beam therapy (PBT) for pediatric patients with advanced neuroblastoma. Methods PBT was conducted at 21 sites in 14 patients with neuroblastoma from 1984 to 2010. Most patients were difficult to treat with photon radiotherapy. Two and 6 patients were classified into stages 3 and 4, respectively, and 6 patients had recurrent disease. Seven of the 8 patients who received PBT as the initial treatment were classified as the high risk group. Twelve patients had gross residual disease before PBT and 2 had undergone intraoperative radiotherapy before PBT. Five patients received PBT for multiple sites, including remote metastases. Photon radiotherapy was used in combination with PBT for 3 patients. The PBT doses ranged from 19.8 to 45.5 GyE (median: 30.6 GyE). Results Seven patients are alive with no evidence of disease, 1 is alive with disease progression, and 6 died due to the tumor. Recurrence in the treatment field was not observed and the 3-year locoregional control rate was 82%. Severe acute radiotoxicity was not observed, but 1 patient had narrowing of the aorta and asymptomatic vertebral compression fracture at 28 years after PBT, and hair loss was prolonged in one patient. Conclusion PBT may be a better alternative to photon radiotherapy for children with advanced neuroblastoma, and may be conducted safely for patients with neuroblastoma that is difficult to manage using photon beams. PMID:23758770

  7. Rare variants in TP53 and susceptibility to neuroblastoma.

    PubMed

    Diskin, Sharon J; Capasso, Mario; Diamond, Maura; Oldridge, Derek A; Conkrite, Karina; Bosse, Kristopher R; Russell, Mike R; Iolascon, Achille; Hakonarson, Hakon; Devoto, Marcella; Maris, John M

    2014-04-01

    TP53 is the most frequently mutated gene in human malignancies; however, de novo somatic mutations in childhood embryonal cancers such as neuroblastoma are rare. We report on the analysis of three independent case-control cohorts comprising 10290 individuals and demonstrate that rs78378222 and rs35850753, rare germline variants in linkage disequilibrium that map to the 3' untranslated region (UTR) of TP53 and 5' UTR of the Δ133 isoform of TP53, respectively, are robustly associated with neuroblastoma (rs35850753: odds ratio [OR] = 2.7, 95% confidence interval [CI] = 2.0 to 3.6, P combined = 3.43×10(-12); rs78378222: OR = 2.3, 95% CI = 1.8 to 2.9, P combined = 2.03×10(-11)). All statistical tests were two-sided. These findings add neuroblastoma to the complex repertoire of human cancers influenced by the rs78378222 hypomorphic allele, which impairs proper termination and polyadenylation of TP53 transcripts. Future studies using whole-genome sequencing data are likely to reveal additional rare variants with large effect sizes contributing to neuroblastoma tumorigenesis. PMID:24634504

  8. Relapsed neuroblastomas show frequent RAS-MAPK pathway mutations.

    PubMed

    Eleveld, Thomas F; Oldridge, Derek A; Bernard, Virginie; Koster, Jan; Daage, Leo Colmet; Diskin, Sharon J; Schild, Linda; Bentahar, Nadia Bessoltane; Bellini, Angela; Chicard, Mathieu; Lapouble, Eve; Combaret, Valérie; Legoix-Né, Patricia; Michon, Jean; Pugh, Trevor J; Hart, Lori S; Rader, JulieAnn; Attiyeh, Edward F; Wei, Jun S; Zhang, Shile; Naranjo, Arlene; Gastier-Foster, Julie M; Hogarty, Michael D; Asgharzadeh, Shahab; Smith, Malcolm A; Guidry Auvil, Jaime M; Watkins, Thomas B K; Zwijnenburg, Danny A; Ebus, Marli E; van Sluis, Peter; Hakkert, Anne; van Wezel, Esther; van der Schoot, C Ellen; Westerhout, Ellen M; Schulte, Johannes H; Tytgat, Godelieve A; Dolman, M Emmy M; Janoueix-Lerosey, Isabelle; Gerhard, Daniela S; Caron, Huib N; Delattre, Olivier; Khan, Javed; Versteeg, Rogier; Schleiermacher, Gudrun; Molenaar, Jan J; Maris, John M

    2015-08-01

    The majority of patients with neuroblastoma have tumors that initially respond to chemotherapy, but a large proportion will experience therapy-resistant relapses. The molecular basis of this aggressive phenotype is unknown. Whole-genome sequencing of 23 paired diagnostic and relapse neuroblastomas showed clonal evolution from the diagnostic tumor, with a median of 29 somatic mutations unique to the relapse sample. Eighteen of the 23 relapse tumors (78%) showed mutations predicted to activate the RAS-MAPK pathway. Seven of these events were detected only in the relapse tumor, whereas the others showed clonal enrichment. In neuroblastoma cell lines, we also detected a high frequency of activating mutations in the RAS-MAPK pathway (11/18; 61%), and these lesions predicted sensitivity to MEK inhibition in vitro and in vivo. Our findings provide a rationale for genetic characterization of relapse neuroblastomas and show that RAS-MAPK pathway mutations may function as a biomarker for new therapeutic approaches to refractory disease. PMID:26121087

  9. N-Cadherin in Neuroblastoma Disease: Expression and Clinical Significance

    PubMed Central

    Derycke, Lara; De Craemer, Annemie; De Brouwer, Sara; De Preter, Katleen; Van Roy, Nadine; Vandesompele, Jo; Speleman, Frank; Philippé, Jan; Benoit, Yves; Beiske, Klaus; Bracke, Marc; Laureys, Geneviève

    2012-01-01

    One of the first and most important steps in the metastatic cascade is the loss of cell-cell and cell-matrix interactions. N-cadherin, a crucial mediator of homotypic and heterotypic cell-cell interactions, might play a central role in the metastasis of neuroblastoma (NB), a solid tumor of neuroectodermal origin. Using Reverse Transcription Quantitative PCR (RT-qPCR), Western blot, immunocytochemistry and Tissue MicroArrays (TMA) we demonstrate the expression of N-cadherin in neuroblastoma tumors and cell lines. All neuroblastic tumors (n = 356) and cell lines (n = 10) expressed various levels of the adhesion protein. The N-cadherin mRNA expression was significantly lower in tumor samples from patients suffering metastatic disease. Treatment of NB cell lines with the N-cadherin blocking peptide ADH-1 (Exherin, Adherex Technologies Inc.), strongly inhibited tumor cell proliferation in vitro by inducing apoptosis. Our results suggest that N-cadherin signaling may play a role in neuroblastoma disease, marking involvement of metastasis and determining neuroblastoma cell viability. PMID:22355346

  10. USING NEUROBLASTOMA CELL LINES TO EXAMINE ORGANOPHOSPHATE NEUROTOXICITY

    EPA Science Inventory

    The need to deploy IN VITRO models to test neurotoxic scribes the use of by industry and government regulatory agencies. his research describes the neuroblastoma cell lines to address the relationship between esterase inhibition and neurotoxic outcome following exposure to organo...

  11. Bilateral Synchronous Ectopic Ethmoid Sinus Olfactory Neuroblastoma: A Case Report

    PubMed Central

    Leon-Soriano, Elena; Alfonso, Carolina; Yebenes, Laura; Garcia-Polo, Julio; Lassaletta, Luis; Gavilan, Javier

    2016-01-01

    Patient: Male, 41 Final Diagnosis: Olfactory neuroblastoma Symptoms: Left nasal obstruction • occasional left epistaxis • headache Medication: None Clinical Procedure: Nasal endoscopic examination • neck palpation • CT • bilateral endoscopic resection • MRI • PET-CT • postoperative radiotherapy Specialty: Otolaryngology Objective: Unusual clinical course Background: Olfactory neuroblastoma (ONB), also known as esthesioneuroblastoma, is a rare malignant head and neck cancer thought to originate from the olfactory epithelium. It typically invades contiguous structures at presentation. We report a very rare case of multifocal and ectopic ONB. Case Report: A 41-year-old man presented with left nasal obstruction and occasional left epistaxis associated with headache. Endoscopic examination of the nasal cavities and computed tomography suggested bilateral polypoid masses. Histopathological diagnosis after endoscopic resection established bilateral olfactory neuroblastoma of the ethmoid sinuses. The patient received postoperative radiotherapy. He remains free of disease 4 years after treatment. Conclusions: To the best of our knowledge this is the second documented case of multifocal ectopic olfactory neuroblastoma. Clinicians should consider ONB in the differential diagnosis of bilateral synchronous nasal and paranasal masses to avoid delayed diagnosis. Endoscopic resection of ONB could be an option in selected cases. PMID:27097989

  12. Tetracycline prevents Aβ oligomer toxicity through an atypical supramolecular interaction.

    PubMed

    Airoldi, Cristina; Colombo, Laura; Manzoni, Claudia; Sironi, Erika; Natalello, Antonino; Doglia, Silvia Maria; Forloni, Gianluigi; Tagliavini, Fabrizio; Del Favero, Elena; Cantù, Laura; Nicotra, Francesco; Salmona, Mario

    2011-01-21

    The antibiotic tetracycline was reported to possess an anti-amyloidogenic activity on a variety of amyloidogenic proteins both in in vitro and in vivo models. To unveil the mechanism of action of tetracycline on Aβ1-40 and Aβ1-42 at both molecular and supramolecular levels, we carried out a series of experiments using NMR spectroscopy, FTIR spectroscopy, dynamic laser light-scattering (DLS) and atomic force microscopy (AFM). Firstly we showed that the co-incubation of Aβ1-42 oligomers with tetracycline hinders the toxicity towards N2a cell lines in a dose-dependent manner. Therefore, the nature of the interaction between the drug and Aβ oligomers was investigated. To carry out NMR and FTIR studies we have prepared Aβ peptide solutions containing assemblies ranging from monomers to large oligomers. Saturation transfer difference (STD) NMR experiments have shown that tetracycline did not interact with monomers at variance with oligomers. Noteworthy, in this latter case we observed that this interaction was very peculiar since the transfer of magnetization from Aβ oligomers to tetracycline involved all drug protons. In addition, intermolecular cross-peaks between tetracycline and Aβ were not observed in NOESY spectra, indicating the absence of a specific binding site and suggesting the occurrence of a supramolecular interaction. DLS and AFM studies supported this hypothesis since the co-dissolution of Aβ peptides and tetracycline triggered the immediate formation of new aggregates that improved the solubility of Aβ peptides, preventing in this way the progression of the amyloid cascade. Moreover, competitive NMR binding experiments showed for the first time that tetracycline competes with thioflavin T (ThT) in the binding to Aβ peptides. Our data shed light on a novel mechanism of anti-amyloidogenic activity displayed by tetracycline, governed by hydrophobic and charge multiparticle interactions. PMID:21063627

  13. Unique Properties of the Rabbit Prion Protein Oligomer

    PubMed Central

    Yu, Ziyao; Huang, Pei; Yu, Yuanhui; Zheng, Zhen; Huang, Zicheng; Guo, Chenyun; Lin, Donghai

    2016-01-01

    Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are a group of fatal neurodegenerative disorders infecting both humans and animals. Recent works have demonstrated that the soluble prion protein oligomer (PrPO), the intermediate of the conformational transformation from the host-derived cellular form (PrPC) to the disease-associated Scrapie form (PrPSc), exerts the major neurotoxicity in vitro and in vivo. Rabbits show strong resistance to TSEs, the underlying mechanism is unclear to date. It is expected that the relative TSEs-resistance of rabbits is closely associated with the unique properties of rabbit prion protein oligomer which remain to be addressed in detail. In the present work, we prepared rabbit prion protein oligomer (recRaPrPO) and human prion protein oligomer (recHuPrPO) under varied conditions, analyzed the effects of pH, NaCl concentration and incubation temperature on the oligomerization, and compared the properties of recRaPrPO and recHuPrPO. We found that several factors facilitated the formation of prion protein oligomers, including low pH, high NaCl concentration, high incubation temperature and low conformational stability of monomeric prion protein. RecRaPrPO was formed more slowly than recHuPrPO at physiological-like conditions (< 57°C, < 150 mM NaCl). Furthermore, recRaPrPO possessed higher susceptibility to proteinase K and lower cytotoxicity in vitro than recHuPrPO. These unique properties of recRaPrPO might substantially contribute to the TSEs-resistance of rabbits. Our work sheds light on the oligomerization of prion proteins and is of benefit to mechanistic understanding of TSEs-resistance of rabbits. PMID:27529173

  14. Unique Properties of the Rabbit Prion Protein Oligomer.

    PubMed

    Yu, Ziyao; Huang, Pei; Yu, Yuanhui; Zheng, Zhen; Huang, Zicheng; Guo, Chenyun; Lin, Donghai

    2016-01-01

    Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are a group of fatal neurodegenerative disorders infecting both humans and animals. Recent works have demonstrated that the soluble prion protein oligomer (PrPO), the intermediate of the conformational transformation from the host-derived cellular form (PrPC) to the disease-associated Scrapie form (PrPSc), exerts the major neurotoxicity in vitro and in vivo. Rabbits show strong resistance to TSEs, the underlying mechanism is unclear to date. It is expected that the relative TSEs-resistance of rabbits is closely associated with the unique properties of rabbit prion protein oligomer which remain to be addressed in detail. In the present work, we prepared rabbit prion protein oligomer (recRaPrPO) and human prion protein oligomer (recHuPrPO) under varied conditions, analyzed the effects of pH, NaCl concentration and incubation temperature on the oligomerization, and compared the properties of recRaPrPO and recHuPrPO. We found that several factors facilitated the formation of prion protein oligomers, including low pH, high NaCl concentration, high incubation temperature and low conformational stability of monomeric prion protein. RecRaPrPO was formed more slowly than recHuPrPO at physiological-like conditions (< 57°C, < 150 mM NaCl). Furthermore, recRaPrPO possessed higher susceptibility to proteinase K and lower cytotoxicity in vitro than recHuPrPO. These unique properties of recRaPrPO might substantially contribute to the TSEs-resistance of rabbits. Our work sheds light on the oligomerization of prion proteins and is of benefit to mechanistic understanding of TSEs-resistance of rabbits. PMID:27529173

  15. Self-assembly of 33-mer gliadin peptide oligomers.

    PubMed

    Herrera, M G; Benedini, L A; Lonez, C; Schilardi, P L; Hellweg, T; Ruysschaert, J-M; Dodero, V I

    2015-11-28

    The 33-mer gliadin peptide, LQLQPF(PQPQLPY)3PQPQPF, is a highly immunogenic peptide involved in celiac disease and probably in other immunopathologies associated with gliadin. Herein, dynamic light scattering measurements showed that 33-mer, in the micromolar concentration range, forms polydisperse nano- and micrometer range particles in aqueous media. This behaviour is reminiscent of classical association of colloids and we hypothesized that the 33-mer peptide self-assembles into micelles that could be the precursors of 33-mer oligomers in water. Deposition of 33-mer peptide aqueous solution on bare mica generated nano- and microstructures with different morphologies as revealed by atomic force microscopy. At 6 μM, the 33-mer is organised in isolated and clusters of spherical nanostructures. In the 60 to 250 μM concentration range, the spherical oligomers associated mainly in linear and annular arrangements and structures adopting a "sheet" type morphology appeared. At higher concentrations (610 μM), mainly filaments and plaques immersed in a background of nanospherical structures were detected. The occurrence of different morphologies of oligomers and finally the filaments suggests that the unique specific geometry of the 33-mer oligomers has a crucial role in the subsequent condensation and organization of their fractal structures into the final filaments. The self-assembly process on mica is described qualitatively and quantitatively by a fractal diffusion limited aggregation (DLA) behaviour with the fractal dimension in the range of 1.62 ± 0.02 to 1.73 ± 0.03. Secondary structure evaluation of the oligomers by Attenuated Total Reflection FTIR spectroscopy (ATR-FTIR) revealed the existence of a conformational equilibrium of self-assembled structures, from an extended conformation to a more folded parallel beta elongated structures. Altogether, these findings provide structural and morphological information about supramolecular organization of the 33-mer

  16. Translational development of difluoromethylornithine (DFMO) for the treatment of neuroblastoma.

    PubMed

    Bassiri, Hamid; Benavides, Adriana; Haber, Michelle; Gilmour, Susan K; Norris, Murray D; Hogarty, Michael D

    2015-07-01

    Neuroblastoma is a childhood tumor in which MYC oncogenes are commonly activated to drive tumor progression. Survival for children with high-risk neuroblastoma remains poor despite treatment that incorporates high-dose chemotherapy, stem cell support, surgery, radiation therapy and immunotherapy. More effective and less toxic treatments are sought and one approach under clinical development involves re-purposing the anti-protozoan drug difluoromethylornithine (DFMO; Eflornithine) as a neuroblastoma therapeutic. DFMO is an irreversible inhibitor of ornithine decarboxylase (Odc), a MYC target gene, bona fide oncogene, and the rate-limiting enzyme in polyamine synthesis. DFMO is approved for the treatment of Trypanosoma brucei gambiense encephalitis ("African sleeping sickness") since polyamines are essential for the proliferation of these protozoa. However, polyamines are also critical for mammalian cell proliferation and the finding that MYC coordinately regulates all aspects of polyamine metabolism suggests polyamines may be required to support cancer promotion by MYC. Pre-emptive blockade of polyamine synthesis is sufficient to block tumor initiation in an otherwise fully penetrant transgenic mouse model of neuroblastoma driven by MYCN, underscoring the necessity of polyamines in this process. Moreover, polyamine depletion regimens exert potent anti-tumor activity in pre-clinical models of established neuroblastoma as well, in combination with numerous chemotherapeutic agents and even in tumors with unfavorable genetic features such as MYCN, ALK or TP53 mutation. This has led to the testing of DFMO in clinical trials for children with neuroblastoma. Current trial designs include testing lower dose DFMO alone (2,000 mg/m(2)/day) starting at the completion of standard therapy, or higher doses combined with chemotherapy (up to 9,000 mg/m(2)/day) for patients with relapsed disease that has progressed. In this review we will discuss important considerations for the

  17. Translational development of difluoromethylornithine (DFMO) for the treatment of neuroblastoma

    PubMed Central

    Bassiri, Hamid; Benavides, Adriana; Haber, Michelle; Gilmour, Susan K.; Norris, Murray D.

    2015-01-01

    Neuroblastoma is a childhood tumor in which MYC oncogenes are commonly activated to drive tumor progression. Survival for children with high-risk neuroblastoma remains poor despite treatment that incorporates high-dose chemotherapy, stem cell support, surgery, radiation therapy and immunotherapy. More effective and less toxic treatments are sought and one approach under clinical development involves re-purposing the anti-protozoan drug difluoromethylornithine (DFMO; Eflornithine) as a neuroblastoma therapeutic. DFMO is an irreversible inhibitor of ornithine decarboxylase (Odc), a MYC target gene, bona fide oncogene, and the rate-limiting enzyme in polyamine synthesis. DFMO is approved for the treatment of Trypanosoma brucei gambiense encephalitis (“African sleeping sickness”) since polyamines are essential for the proliferation of these protozoa. However, polyamines are also critical for mammalian cell proliferation and the finding that MYC coordinately regulates all aspects of polyamine metabolism suggests polyamines may be required to support cancer promotion by MYC. Pre-emptive blockade of polyamine synthesis is sufficient to block tumor initiation in an otherwise fully penetrant transgenic mouse model of neuroblastoma driven by MYCN, underscoring the necessity of polyamines in this process. Moreover, polyamine depletion regimens exert potent anti-tumor activity in pre-clinical models of established neuroblastoma as well, in combination with numerous chemotherapeutic agents and even in tumors with unfavorable genetic features such as MYCN, ALK or TP53 mutation. This has led to the testing of DFMO in clinical trials for children with neuroblastoma. Current trial designs include testing lower dose DFMO alone (2,000 mg/m2/day) starting at the completion of standard therapy, or higher doses combined with chemotherapy (up to 9,000 mg/m2/day) for patients with relapsed disease that has progressed. In this review we will discuss important considerations for the

  18. Right adrenal gland neuroblastoma infiltrating the liver and mimicking mesenchymal hamartoma: A case report

    PubMed Central

    Abo-Elenain, Ahmed; Naiem, Yousif; Hamedhosam-eldin@hotmail.com, Hosam; Emam, Mohamed; Elkashef, Wagdi; AbdelRafee, Ahmed

    2015-01-01

    Introduction Neuroblastoma is the most common extracranial solid pediatric malignancy. The most common site is abdomen with predominance of suprarenal medulla. Infiltration of the tumour to the liver is rare. No cases were reported in the literature about the misdiagnosis of neuroblastoma as mesenchymal hamartoma in the liver. Presentation of case We represent a rare case of neuroblastoma misdiagnosed as mesenchymal hamartoma in liver in a six-month-old female infant presented with fever and abdominal mass. Abdominal computed tomography (CT) revealed large cystic lesion occupying most of the right liver enchroaching upon right suprarenal region and displacing the right kidney inferior suggestive for mesenchymal hamartoma. Right adrenalectomy with en-bloc resection of the adjacent liver segments was done. Postoperative pathology revealed neuroblastoma with positive specific immunohistochemistry (IHC). Discussion Although neuroblastoma is the second most common pediatric abdominal malignancy with specific diagnostic modalities, a misdiagnosis of a case with neuroblastoma as mesenchymal hamartoma is rare. Histopathological diagnosis of neuroblastoma with positive IHC is essential as shown in our case. Conclusion We represent a rare case of neuroblastoma which arose from the right adrenal gland and infiltrated the adjacent liver substance mimicking mesenchymal hamartoma of the liver. Neuroblastoma is rarely presented with pyrexia of unknown origin. Neuroblastoma should be considered in differential diagnosis of abdominal mass in all infants and children. PMID:26036461

  19. The emerging molecular pathogenesis of neuroblastoma: implications for improved risk assessment and targeted therapy

    PubMed Central

    2009-01-01

    Neuroblastoma is one of the most common solid tumors of childhood, arising from immature sympathetic nervous system cells. The clinical course of patients with neuroblastoma is highly variable, ranging from spontaneous regression to widespread metastatic disease. Although the outcome for children with cancer has improved considerably during the past decades, the prognosis of children with aggressive neuroblastoma remains dismal. The clinical heterogeneity of neuroblastoma mirrors the biological and genetic heterogeneity of these tumors. Ploidy and MYCN amplification have been used as genetic markers for risk stratification and therapeutic decision making, and, more recently, gene expression profiling and genome-wide DNA copy number analysis have come into the picture as sensitive and specific tools for assessing prognosis. The applica tion of new genetic tools also led to the discovery of an important familial neuroblastoma cancer gene, ALK, which is mutated in approximately 8% of sporadic tumors, and genome-wide association studies have unveiled loci with risk alleles for neuroblastoma development. For some of the genomic regions that are deleted in some neuroblastomas, on 1p, 3p and 11q, candidate tumor suppressor genes have been identified. In addition, evidence has emerged for the contribution of epigenetic disturbances in neuroblastoma oncogenesis. As in other cancer entities, altered microRNA expression is also being recognized as an important player in neuroblastoma. The recent successes in unraveling the genetic basis of neuroblastoma are now opening opportunities for development of targeted therapies. PMID:19638189

  20. Designed Glycopeptidomimetics Disrupt Protein-Protein Interactions Mediating Amyloid β-Peptide Aggregation and Restore Neuroblastoma Cell Viability.

    PubMed

    Kaffy, Julia; Brinet, Dimitri; Soulier, Jean-Louis; Correia, Isabelle; Tonali, Nicolo; Fera, Katia Fabiana; Iacone, Yasmine; Hoffmann, Anaïs R F; Khemtémourian, Lucie; Crousse, Benoit; Taylor, Mark; Allsop, David; Taverna, Myriam; Lequin, Olivier; Ongeri, Sandrine

    2016-03-10

    How anti-Alzheimer's drug candidates that reduce amyloid 1-42 peptide fibrillization interact with the most neurotoxic species is far from being understood. We report herein the capacity of sugar-based peptidomimetics to inhibit both Aβ1-42 early oligomerization and fibrillization. A wide range of bio- and physicochemical techniques, such as a new capillary electrophoresis method, nuclear magnetic resonance, and surface plasmon resonance, were used to identify how these new molecules can delay the aggregation of Aβ1-42. We demonstrate that these molecules interact with soluble oligomers in order to maintain the presence of nontoxic monomers and to prevent fibrillization. These compounds totally suppress the toxicity of Aβ1-42 toward SH-SY5Y neuroblastoma cells, even at substoichiometric concentrations. Furthermore, demonstration that the best molecule combines hydrophobic moieties, hydrogen bond donors and acceptors, ammonium groups, and a hydrophilic β-sheet breaker element provides valuable insight for the future structure-based design of inhibitors of Aβ1-42 aggregation. PMID:26789783

  1. Quaternary structure defines a large class of amyloid-β oligomers neutralized by sequestration

    PubMed Central

    Liu, Peng; Reed, Miranda N.; Kotilinek, Linda A.; Grant, Marianne K.O.; Forster, Colleen L.; Qiang, Wei; Shapiro, Samantha L.; Reichl, John H.; Chiang, Angie C.A.; Jankowsky, Joanna L.; Wilmot, Carrie M.; Cleary, James P.; Zahs, Kathleen R.; Ashe, Karen H.

    2015-01-01

    Summary The accumulation of amyloid-β (Aβ) as amyloid fibrils and toxic oligomers is an important step in the development of Alzheimer's disease (AD). However, there are numerous potentially toxic oligomers and little is known about their neurological effects when generated in the living brain. Here, we show that Aβ oligomers can be assigned to one of at least two classes (Type 1 and Type 2) based on their temporal, spatial and structural relationships to amyloid fibrils. The Type 2 oligomers are related to amyloid fibrils and represent the majority of oligomers generated in vivo, but remain confined to the vicinity of amyloid plaques and do not impair cognition at levels relevant to AD. Type 1 oligomers are unrelated to amyloid fibrils and may have greater potential to cause global neural dysfunction in AD because they are dispersed. These results refine our understanding of the pathogenicity of Aβ oligomers in vivo. PMID:26051935

  2. Neuroblastoma patient-derived orthotopic xenografts retain metastatic patterns and geno- and phenotypes of patient tumours

    PubMed Central

    Braekeveldt, Noémie; Wigerup, Caroline; Gisselsson, David; Mohlin, Sofie; Merselius, My; Beckman, Siv; Jonson, Tord; Börjesson, Anna; Backman, Torbjörn; Tadeo, Irene; Berbegall, Ana P; Öra, Ingrid; Navarro, Samuel; Noguera, Rosa; Påhlman, Sven; Bexell, Daniel

    2015-01-01

    Neuroblastoma is a childhood tumour with heterogeneous characteristics and children with metastatic disease often have a poor outcome. Here we describe the establishment of neuroblastoma patient-derived xenografts (PDXs) by orthotopic implantation of viably cryopreserved or fresh tumour explants of patients with high risk neuroblastoma into immunodeficient mice. In vivo tumour growth was monitored by magnetic resonance imaging and fluorodeoxyglucose–positron emission tomography. Neuroblastoma PDXs retained the undifferentiated histology and proliferative capacity of their corresponding patient tumours. The PDXs expressed neuroblastoma markers neural cell adhesion molecule, chromogranin A, synaptophysin and tyrosine hydroxylase. Whole genome genotyping array analyses demonstrated that PDXs retained patient-specific chromosomal aberrations such as MYCN amplification, deletion of 1p and gain of chromosome 17q. Thus, neuroblastoma PDXs recapitulate the hallmarks of high-risk neuroblastoma in patients. PDX-derived cells were cultured in serum-free medium where they formed free-floating neurospheres, expressed neuroblastoma gene markers MYCN, CHGA, TH, SYP and NPY, and retained tumour-initiating and metastatic capacity in vivo. PDXs showed much higher degree of infiltrative growth and distant metastasis as compared to neuroblastoma SK-N-BE(2)c cell line-derived orthotopic tumours. Importantly, the PDXs presented with bone marrow involvement, a clinical feature of aggressive neuroblastoma. Thus, neuroblastoma PDXs serve as clinically relevant models for studying and targeting high-risk metastatic neuroblastoma. What's new? Neuroblastoma is a childhood tumour with heterogeneous characteristics and children with metastatic disease have a poor outcome. Here, the authors established neuroblastoma patient-derived xenografts (PDXs) by orthotopic implantation of viably cryopreserved or fresh tumour explants of patients with high-risk neuroblastoma into immunodeficient mice

  3. An electric nose based on arylenevinylene polymers and oligomers

    NASA Astrophysics Data System (ADS)

    de Wit, Michael

    An electronic nose is an instrument, which comprises an array of electronic chemical sensors with partial specificity and an appropriate pattern-recognition system, capable of recognising simple or complex odours. Our efforts are centred around the sensors part of the nose. In fact, we applied a number of polymeric and oligomeric members of the arylenevinylene group of molecules as the active layer for conductimetric sensors (chemiresistors). The electric resistance of the active layer changes when it is exposed to vapors. The response of the sensor on a vapour is defined as the fractional, percentual change of the resistance compared to that in clean air. We made the sensors by depositing the organic layers on a substrate containing pre-printed gold contacts. At first we tested poly(2,5-thienylene vinylene) (PTV). A synthetic method was employed in which a soluble methoxy-precursor polymer of PTV was isolated, which was then spin-coated onto the substrate, and after being converted thermally to PTV, subsequently doped by iodine. The values of the responses of the PTV sensors are comparable to those sensors based on other conducting polymers, but the (partial) selectivity for the vapors is different. The responses of the PTV sensor are linearly related to the concentration. Incomplete conversion of the precursor polymer to the final PTV leads to copolymers of methoxy-PTV and PTV itself varying inter alia in the degree of conjugation. Chemiresistors based on these new materials show an affinity to vapors differing from that of PTV. We discovered that the arylenevinylenes need not to be of polymeric nature for this application. In fact, the arylenevinylene oligomers perform better. The oligomers are easier to modify and to process than polymers. We tested 2,5-dimethoxy-1,4-bis(3,4,5-trimethoxystyrylbenzene) (OMT) in its pure form and in blends with polycarbonate. The responses of these oligomeric sensors are on the average five times higher than those of the

  4. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    SciTech Connect

    Qiao, Jingbo; Paul, Pritha; Lee, Sora; Qiao, Lan; Josifi, Erlena; Tiao, Joshua R.; Chung, Dai H.

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  5. Percutaneous transhepatic biliary drainage in an infant with obstructive jaundice caused by neuroblastoma.

    PubMed

    Saettini, Francesco; Agazzi, Roberto; Giraldi, Eugenia; Foglia, Carlo; Cavalleri, Laura; Morali, Laura; Fasolini, Giorgio; Spotti, Angelica; Provenzi, Massimo

    2015-04-01

    Neuroblastoma presenting with obstructive jaundice is a rare event. Management of this condition includes surgery, chemotherapy, radiotherapy, temporary cholecystostomy tube, endoscopic retrograde cholangiopancreatography (ERCP), and internal biliary drainage (IBD). We herein describe our experience with one infant affected by neuroblastoma presenting with jaundice, who successfully underwent percutaneous transhepatic biliary drainage (PTBD). This report introduces PTBD as a viable treatment option for neuroblastoma and obstructive jaundice and provides a review of the pertinent literature. PMID:25551550

  6. Treatment of neuroblastoma with /sup 131/I-metaiodobenzylguanidine: experience of the Muenster/Kassel Group

    SciTech Connect

    Fischer, M.; Wehinger, H.; Kraus, C.; Ritter, J.; Schroeter, W.

    1987-01-01

    I-131-metaiodobenzylguanidine was used for treatment of neuroblastoma stage IV in three children after surgery and or chemotherapy had failed to be effective. In two of the children with multilocular lesions, after an impressive improvement of clinical symptoms tumor progression was observed. Because in about 25% of children with relapsing neuroblastoma complete remission may be achieved by combining surgery, chemotherapy, and I-131-MIBG treatment, this therapeutic modality should be included in the therapeutic strategy of stage III and IV neuroblastoma.

  7. Cancer Stem Cells and Their Interaction with the Tumor Microenvironment in Neuroblastoma

    PubMed Central

    Garner, Evan F.; Beierle, Elizabeth A.

    2015-01-01

    Neuroblastoma, a solid tumor arising from neural crest cells, accounts for over 15% of all pediatric cancer deaths. The interaction of neuroblastoma cancer-initiating cells with their microenvironment likely plays an integral role in the maintenance of resistant disease and tumor relapse. In this review, we discuss the interaction between neuroblastoma cancer-initiating cells and the elements of the tumor microenvironment and how these interactions may provide novel therapeutic targets for this difficult to treat disease. PMID:26729169

  8. Phase transition in conjugated oligomers suspended in chloroform

    NASA Astrophysics Data System (ADS)

    Dwivedi, Shikha; Kumar, Anupam; Yadav, S. N. S.; Mishra, Pankaj

    2015-08-01

    Density functional theory (DFT) has been used to investigate the isotropic-nematic (I-N) phase transition in a system of high aspect ratio conjugated oligomers suspended in chloroform. The interaction between the oligomers is modeled using Gay-Berne potential in which effect of solvent is implicit. Percus-Yevick integral equation theory has been used to evaluate the pair correlation functions of the fluid phase at several temperatures and densities. These pair correlation function has been used in the DFT to evaluate the I-N freezing parameters. Highly oriented nematic is found to stabilize at low density. The results obtained are in qualitative agreement with the simulation and are verifiable.

  9. Synthesis of long Prebiotic Oligomers on Mineral Surfaces

    NASA Technical Reports Server (NTRS)

    Ferris, James P.; Hill, Aubrey R., Jr.; Liu, Rihe; Orgel, Leslie E.

    1996-01-01

    Most theories of the origin of biological organization assume that polymers with lengths in the range of 30-60 monomers are needed to make a genetic system viable. But it has not proved possible to synthesize plausibly prebiotic polymers this long by condensation in aqueous solution, because hydrolysis competes with polymerization. The potential of mineral surfaces to facilitate prebiotic polymerization was pointed out long ago. Here we describe a system that models prebiotic polymerization by the oligomerization of activated monomers -both nucleotides and amino acids. We find that whereas the reactions in solution produce only short oligomers (the longest typically being a 10-mer), the presence of mineral surfaces (montmorillonite for nucleotides, illite and hydroxylapatite for amino adds) induces the formation of oligomers up to 55 monomers long. These are formed by successive "feedings" with the monomers; polymerization takes place on the mineral surfaces in a manner akin to solid-phase synthesis of biopolymers.

  10. Pigment oligomers as natural and artificial photosynthetic antennas

    SciTech Connect

    Blankenship, R.E.

    1996-12-31

    Green photosynthetic bacteria contain antenna complexes known as chlorosomes. These complexes are appressed to the cytoplasmic side of the inner cell membrane and function to absorb light and transfer the energy to the photochemical reaction center, where photochemical energy storage takes place. Chlorosomes differ from all other known photosynthetic antenna complexes in that the geometrical arrangement of pigments is determined primarily by pigment-pigment interactions instead of pigment-protein interactions. The bacteriochlorophyll c, d or e pigments found in chlorosomes form large oligomers with characteristic spectral properties significantly perturbed from those exhibited by monomeric pigments. Because of their close spatial interaction, the pigments are thought to be strongly coupled electronically, and many of the optical properties result from exciton interactions. This presentation will summarize existing knowledge on the chemical composition and properties of chlorosomes, the evidence for the oligomeric nature of chlorosome pigment organization and proposed structures for the oligomers, and the kinetics and mechanisms of energy transfer in chlorosomes.