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1.
Int J Mol Sci ; 25(13)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38999942

RESUMEN

Familial episodic pain syndrome (FEPS) is an early childhood onset disorder of severe episodic limb pain caused mainly by pathogenic variants of SCN11A, SCN10A, and SCN9A, which encode three voltage-gated sodium channels (VGSCs) expressed as key determinants of nociceptor excitability in primary sensory neurons. There may still be many undiagnosed patients with FEPS. A better understanding of the associated pathogenesis, epidemiology, and clinical characteristics is needed to provide appropriate diagnosis and care. For this study, nationwide recruitment of Japanese patients was conducted using provisional clinical diagnostic criteria, followed by genetic testing for SCN11A, SCN10A, and SCN9A. In the cohort of 212 recruited patients, genetic testing revealed that 64 patients (30.2%) harbored pathogenic or likely pathogenic variants of these genes, consisting of 42 (19.8%), 14 (6.60%), and 8 (3.77%) patients with variants of SCN11A, SCN10A, and SCN9A, respectively. Meanwhile, the proportions of patients meeting the tentative clinical criteria were 89.1%, 52.0%, and 54.5% among patients with pathogenic or likely pathogenic variants of each of the three genes, suggesting the validity of these clinical criteria, especially for patients with SCN11A variants. These clinical diagnostic criteria of FEPS will accelerate the recruitment of patients with underlying pathogenic variants who are unexpectedly prevalent in Japan.


Asunto(s)
Pruebas Genéticas , Canal de Sodio Activado por Voltaje NAV1.7 , Canal de Sodio Activado por Voltaje NAV1.8 , Canal de Sodio Activado por Voltaje NAV1.9 , Humanos , Canal de Sodio Activado por Voltaje NAV1.7/genética , Canal de Sodio Activado por Voltaje NAV1.9/genética , Japón/epidemiología , Canal de Sodio Activado por Voltaje NAV1.8/genética , Masculino , Femenino , Pruebas Genéticas/métodos , Adulto , Adolescente , Niño , Predisposición Genética a la Enfermedad , Adulto Joven , Preescolar , Mutación , Dolor , Recto/anomalías
2.
Biochem Genet ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39058404

RESUMEN

Familial episodic pain syndrome (FEPS) is an autosomal-dominant inherited disorder characterized by paroxysmal pain episodes. FEPS appears in early childhood, gradually disappearing with age, and pain episodes can be triggered by fatigue, bad weather, and cold temperatures. Several gain-of-function variants have been reported for SCN9A, SCN10A, or SCN11A, which encode the voltage-gated sodium channel α subunits Nav1.7, Nav1.8, and Nav1.9, respectively. In this study, we conducted genetic analysis in a four-generation Japanese pedigree. The proband was a 7-year-old girl, and her brother, sister, mother, and grandmother were also experiencing or had experienced pain episodes and were considered to be affected. The father was unaffected. Sequencing of SCN9A, SCN10A, and SCN11A in the proband revealed a novel heterozygous variant of SCN11A: g.38894937G>A (c.2431C>T, p.Leu811Phe). This variant was confirmed in other affected members but not in the unaffected father. The affected residue, Leu811, is located within the DII/S6 helix of Nav1.9 and is important for signal transduction from the voltage-sensing domain and pore opening. On the other hand, the c.2432T>C (p.Leu811Pro) variant is known to cause congenital insensitivity to pain (CIP). Molecular dynamics simulations showed that p.Leu811Phe increased the structural stability of Nav1.9 and prevented the necessary conformational changes, resulting in changes in the dynamics required for function. By contrast, CIP-related p.Leu811Pro destabilized Nav1.9. Thus, we speculate that p.Leu811Phe may lead to current leakage, while p.Leu811Pro can increase the current through Nav1.9.

3.
iScience ; 27(2): 108997, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38327785

RESUMEN

The neuromuscular junction (NMJ) forms centrally in myotubes and, as the only synapse between motor neuron and myotube, are indispensable for motor activity. The midmuscle formation of NMJs, including midmuscle-restricted expression of NMJ-related genes, is governed by the muscle-specific kinase (MuSK). However, mechanisms underlying MuSK-mediated signaling are unclear. Here, we find that the Calcium-binding protein 7 (Cabp7) gene shows midmuscle-restricted expression, and muscle-specific depletion of Cabp7 in mice accelerated age-related NMJ degeneration, muscle weakness/atrophy, and motor dysfunction. Surprisingly, forced expression in muscle of CIP, an inhibitory peptide of the negative regulator of NMJ formation cyclin-dependent kinase 5 (Cdk5), restored NMJ integrity and muscle strength, and healed muscle atrophy in muscle-specific Cabp7-deficient mice, which showed increased muscle expression of the Cdk5 activator p25. These findings together demonstrate that MuSK-mediated signaling induces muscle expression of Cabp7, which suppresses age-related NMJ degeneration likely by attenuating p25 expression, providing insights into prophylactic/therapeutic intervention against age-related motor dysfunction.

4.
Biochem Biophys Res Commun ; 525(3): 668-674, 2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-32139119

RESUMEN

Moyamoya disease (MMD) is a cerebrovascular disease characterized by progressive occlusion of the internal carotid arteries. Genetic studies originally identified RNF213 as an MMD susceptibility gene that encodes a large 591 kDa protein with a functional RING domain and dual AAA+ ATPase domains. As the functions of RNF213 and its relationship to MMD onset are unknown, we set out to characterize the ubiquitin ligase activity of RNF213, and the effects of MMD patient mutations on these activities and on other cellular processes. In vitro ubiquitination assays, using the RNF213 RING domain, identified Ubc13/Uev1A as a key ubiquitin conjugating enzyme that together generate K63-linked polyubiquitin chains. However, nearly all MMD patient mutations in the RING domain greatly reduced this activity. When full-length proteins were overexpressed in HEK293T cells, patient mutations that abolished the ubiquitin ligase activities conversely enhanced nuclear factor κB (NFκB) activation and induced apoptosis accompanied with Caspase-3 activation. These induced activities were dependent on the RNF213 AAA+ domain. Our results suggest that the NFκB- and apoptosis-inducing functions of RNF213 may be negatively regulated by its ubiquitin ligase activity and that disruption of this regulation could contribute towards MMD onset.


Asunto(s)
Dominio AAA , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Apoptosis , Enfermedad de Moyamoya/genética , Mutación/genética , FN-kappa B/metabolismo , Dominios RING Finger , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/genética , Secuencia de Aminoácidos , Células HEK293 , Humanos , Lisina/metabolismo , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Poliubiquitina/metabolismo , Factores de Transcripción/metabolismo , Enzimas Ubiquitina-Conjugadoras/metabolismo
5.
Biochem Biophys Res Commun ; 523(1): 214-219, 2020 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-31848047

RESUMEN

Neuromuscular junctions (NMJs) are cholinergic synapses characterized by ultrastructural specializations, including the presynaptic active zones, the acetylcholine (ACh) release sites of the motor nerve terminal, and the postsynaptic junctional folds of muscle membrane, where ACh receptors (AChRs) cluster for efficient neuromuscular transmission. The formation and maintenance of NMJs are governed by the muscle-specific receptor tyrosine kinase MuSK. We had previously demonstrated that the muscle cytoplasmic protein Dok-7 is an essential activator of MuSK, and its activation and NMJ formation are enhanced in the Dok-7 transgenic (Tg) mice, in which Dok-7 is specifically overexpressed in skeletal muscle. Although Dok-7 Tg mice develop abnormally large NMJs but show normal motor function, the forced expression of Dok-7 in the muscle improves impaired motor activity in mouse models of neuromuscular disorders with NMJ defects. However, the effect of Dok-7 overexpression in skeletal muscle on ultrastructure and neuromuscular transmission of NMJs is yet to be studied. Here, we investigated the structural and electrophysiological properties of NMJs in the diaphragm muscle of 8-week-old Dok-7 Tg mice. The areas of the presynaptic motor nerve terminals and postsynaptic muscle membrane of NMJs were 2.7 and 4.3 times greater in Dok-7 Tg mice than in WT mice, respectively. Electrophysiological analyses revealed that neuromuscular transmission via NMJs in Dok-7 Tg mice was significantly enhanced but not proportionally with the increased size of the synaptic contact. Consistent with this, the densities of active zones and synaptic vesicles (ACh carriers) in the presynaptic motor nerve terminals were reduced. In addition, the density and size of postsynaptic junctional folds in the muscle membrane were also reduced. Moreover, terminal Schwann cells exhibited significantly greater penetration of their processes into the synaptic clefts, which connect the pre- and post-synaptic specializations. Together, our findings demonstrate that transgenic overexpression of Dok-7 in the skeletal muscle enhances neuromuscular transmission with significant enlargement and ultrastructural alterations of NMJs, the latter of which might prevent toxic overactivation of AChRs at the abnormally enlarged NMJs.


Asunto(s)
Proteínas Musculares/biosíntesis , Músculo Esquelético/metabolismo , Unión Neuromuscular/metabolismo , Transmisión Sináptica , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Unión Neuromuscular/química
6.
EMBO Mol Med ; 9(7): 880-889, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28490573

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a progressive, multifactorial motor neurodegenerative disease with severe muscle atrophy. The glutamate release inhibitor riluzole is the only medication approved by the FDA, and prolongs patient life span by a few months, testifying to a strong need for new treatment strategies. In ALS, motor neuron degeneration first becomes evident at the motor nerve terminals in neuromuscular junctions (NMJs), the cholinergic synapse between motor neuron and skeletal muscle; degeneration then progresses proximally, implicating the NMJ as a therapeutic target. We previously demonstrated that activation of muscle-specific kinase MuSK by the cytoplasmic protein Dok-7 is essential for NMJ formation, and forced expression of Dok-7 in muscle activates MuSK and enlarges NMJs. Here, we show that therapeutic administration of an adeno-associated virus vector encoding the human DOK7 gene suppressed motor nerve terminal degeneration at NMJs together with muscle atrophy in the SOD1-G93A ALS mouse model. Ultimately, we show that DOK7 gene therapy enhanced motor activity and life span in ALS model mice.


Asunto(s)
Esclerosis Amiotrófica Lateral/terapia , Terapia Genética , Actividad Motora , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Adenoviridae/genética , Animales , Modelos Animales de Enfermedad , Vectores Genéticos , Humanos , Longevidad , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Degeneración Nerviosa/terapia , Unión Neuromuscular/fisiología , Resultado del Tratamiento
7.
Clin Calcium ; 27(3): 413-419, 2017.
Artículo en Japonés | MEDLINE | ID: mdl-28232656

RESUMEN

The mammalian neuromuscular junction(NMJ), a cholinergic synapse between a motor neuron and a skeletal muscle fiber, is essential for neural control of muscle contraction. Impaired formation and/or maintenance of NMJs results in disorders of neuromuscular transmission such as myasthenia gravis(MG)and congenital myasthenic syndromes(CMSs). The formation and maintenance of NMJs are orchestrated by the muscle-specific receptor tyrosine kinase MuSK. Activation of MuSK involves its essential cytoplasmic activator Dok-7, the MuSK co-receptor Lrp4, and the motor neuron-derived MuSK activator agrin. Indeed, CMS-associated mutations are identified in the genes encoding these 4 proteins, and autoantibodies against MuSK, Lrp4, or agrin are found in MG patients, demonstrating the pathophysiological significance of the MuSK activation machinery. However, Lrp4 and agrin also play crucial roles separate from MuSK activation in NMJ formation and maintenance. Based on the finding that forced expression of Dok-7 in muscle activates MuSK and enlarges NMJs, we recently developed DOK7 gene therapy as a therapy aimed at enlarging the NMJ, which has potential for treating various neuromuscular disorders with defective NMJ structure.


Asunto(s)
Enfermedades Musculares/tratamiento farmacológico , Unión Neuromuscular , Animales , Terapia Genética , Humanos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Enfermedades Musculares/genética , Enfermedades Musculares/terapia , Unión Neuromuscular/metabolismo
8.
J Biochem ; 161(3): 269-277, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28069867

RESUMEN

As the synapse between a motor neuron and skeletal muscle, the neuromuscular junction (NMJ) is required for muscle contraction. The formation and maintenance of NMJs are controlled by the muscle-specific receptor kinase MuSK. Dok-7 is the essential cytoplasmic activator of MuSK, and indeed mice lacking Dok-7 form no NMJs. Moreover, DOK7 gene mutations underlie DOK7 myasthenia, an NMJ synaptopathy. Previously, we failed to detect MuSK activation in myotubes by Dok-7 mutated in the N-terminal pleckstrin homology (PH) or phosphotyrosine binding (PTB) domain or that lacked the C-terminal region (Dok-7-ΔC). Here, we found by quantitative analysis that Dok-7-ΔC marginally, but significantly, activated MuSK in myotubes, unlike the PH- or PTB-mutant. Purified, recombinant Dok-7-ΔC, but not other mutants, also showed marginal ability to activate MuSK's cytoplasmic portion, carrying the kinase domain. Consistently, forced expression of Dok-7-ΔC rescued Dok-7-deficient mice from neonatal lethality caused by the lack of NMJs, indicating restored MuSK activation and NMJ formation. However, these mice showed only marginal activation of MuSK and died by 3 weeks of age apparently due to an abnormally small number and size of NMJs. Thus, Dok-7's C-terminal region plays a key, but not fully essential, role in MuSK activation and NMJ formation.


Asunto(s)
Proteínas Musculares/química , Proteínas Musculares/metabolismo , Unión Neuromuscular/enzimología , Unión Neuromuscular/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Células Cultivadas , Ratones
9.
Genes Cells ; 21(6): 670-6, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27091576

RESUMEN

The neuromuscular junction (NMJ) is a synapse between a motor neuron and skeletal muscle and is required for muscle contraction. The formation and maintenance of NMJs are governed by the muscle-specific receptor tyrosine kinase MuSK. We previously showed that the muscle cytoplasmic protein Dok-7 is an essential activator of MuSK. Indeed, mice lacking either Dok-7 or MuSK form no NMJs, and defects in the human DOK7 gene underlie a congenital myasthenic syndrome (an NMJ disorder). However, it remains unproven whether Dok-7 is required for the postnatal maintenance of NMJs. In this study, we generated recombinant adeno-associated virus (AAV) vectors encoding short hairpin RNAs targeting the mouse dok-7 gene (AAV-shD7). Systemic administration of AAV-shD7 into 2-week-old mice down-regulated dok-7 expression in muscle and induced myasthenic symptoms including reduction in body weight and motor function. Moreover, AAV-shD7 treatment suppressed MuSK-dependent gene expression of NMJ components and reduced the size of NMJs. These results demonstrate that correct, physiological levels of dok-7 expression are required for the postnatal maintenance of NMJs.


Asunto(s)
Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Miastenia Gravis/genética , Unión Neuromuscular/metabolismo , Animales , Técnicas de Silenciamiento del Gen , Vectores Genéticos , Ratones , Ratones Endogámicos C57BL , Miastenia Gravis/metabolismo , Miastenia Gravis/patología , ARN Interferente Pequeño/metabolismo
10.
Proc Natl Acad Sci U S A ; 111(46): 16556-61, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25368159

RESUMEN

The motoneural control of skeletal muscle contraction requires the neuromuscular junction (NMJ), a midmuscle synapse between the motor nerve and myotube. The formation and maintenance of NMJs are orchestrated by the muscle-specific receptor tyrosine kinase (MuSK). Motor neuron-derived agrin activates MuSK via binding to MuSK's coreceptor Lrp4, and genetic defects in agrin underlie a congenital myasthenic syndrome (an NMJ disorder). However, MuSK-dependent postsynaptic differentiation of NMJs occurs in the absence of a motor neuron, indicating a need for nerve/agrin-independent MuSK activation. We previously identified the muscle protein Dok-7 as an essential activator of MuSK. Although NMJ formation requires agrin under physiological conditions, it is dispensable for NMJ formation experimentally in the absence of the neurotransmitter acetylcholine, which inhibits postsynaptic specialization. Thus, it was hypothesized that MuSK needs agrin together with Lrp4 and Dok-7 to achieve sufficient activation to surmount inhibition by acetylcholine. Here, we show that forced expression of Dok-7 in muscle enhanced MuSK activation in mice lacking agrin or Lrp4 and restored midmuscle NMJ formation in agrin-deficient mice, but not in Lrp4-deficient mice, probably due to the loss of Lrp4-dependent presynaptic differentiation. However, these NMJs in agrin-deficient mice rapidly disappeared after birth, and postsynaptic specializations emerged ectopically throughout myotubes whereas exogenous Dok-7-mediated MuSK activation was maintained. These findings demonstrate that the MuSK activator agrin plays another role essential for the postnatal maintenance, but not for embryonic formation, of NMJs and also for the postnatal, but not prenatal, midmuscle localization of postsynaptic specializations, providing physiological and pathophysiological insight into NMJ homeostasis.


Asunto(s)
Agrina/fisiología , Unión Neuromuscular/enzimología , Proteínas Tirosina Quinasas Receptoras/metabolismo , Agrina/deficiencia , Agrina/genética , Empalme Alternativo , Animales , Diafragma/embriología , Diafragma/crecimiento & desarrollo , Activación Enzimática , Femenino , Proteínas Relacionadas con Receptor de LDL , Longevidad/genética , Masculino , Ratones , Ratones Transgénicos , Fibras Musculares Esqueléticas/enzimología , Fibras Musculares Esqueléticas/fisiología , Proteínas Musculares/deficiencia , Proteínas Musculares/fisiología , Unión Neuromuscular/embriología , Unión Neuromuscular/crecimiento & desarrollo , Enfermedades de la Unión Neuromuscular/enzimología , Enfermedades de la Unión Neuromuscular/genética , Enfermedades de la Unión Neuromuscular/fisiopatología , Fosforilación , Densidad Postsináptica/fisiología , Procesamiento Proteico-Postraduccional , Receptores Colinérgicos/fisiología , Receptores de LDL/deficiencia , Receptores de LDL/fisiología , Proteínas Recombinantes de Fusión/metabolismo , Prueba de Desempeño de Rotación con Aceleración Constante
11.
Science ; 345(6203): 1505-8, 2014 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-25237101

RESUMEN

The neuromuscular junction (NMJ) is the synapse between a motor neuron and skeletal muscle. Defects in NMJ transmission cause muscle weakness, termed myasthenia. The muscle protein Dok-7 is essential for activation of the receptor kinase MuSK, which governs NMJ formation, and DOK7 mutations underlie familial limb-girdle myasthenia (DOK7 myasthenia), a neuromuscular disease characterized by small NMJs. Here, we show in a mouse model of DOK7 myasthenia that therapeutic administration of an adeno-associated virus (AAV) vector encoding the human DOK7 gene resulted in an enlargement of NMJs and substantial increases in muscle strength and life span. When applied to model mice of another neuromuscular disorder, autosomal dominant Emery-Dreifuss muscular dystrophy, DOK7 gene therapy likewise resulted in enlargement of NMJs as well as positive effects on motor activity and life span. These results suggest that therapies aimed at enlarging the NMJ may be useful for a range of neuromuscular disorders.


Asunto(s)
Terapia Genética/métodos , Proteínas Musculares/genética , Músculo Esquelético/inervación , Distrofia Muscular de Cinturas/patología , Distrofia Muscular de Cinturas/terapia , Unión Neuromuscular/patología , Animales , Dependovirus , Modelos Animales de Enfermedad , Femenino , Vectores Genéticos/administración & dosificación , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Esquelético/fisiopatología , Distrofia Muscular de Cinturas/genética
12.
FEBS Lett ; 587(23): 3749-54, 2013 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-24140340

RESUMEN

Low-density lipoprotein receptor-related protein 4 (Lrp4) is essential for pre- and post-synaptic specialization at the neuromuscular junction (NMJ), an indispensable synapse between a motor nerve and skeletal muscle. Muscle-specific receptor tyrosine kinase MuSK must form a complex with Lrp4 to organize postsynaptic specialization at NMJs. Here, we show that the chaperon Mesdc2 binds to the intracellular form of Lrp4 and promotes its glycosylation and cell-surface expression. Furthermore, knockdown of Mesdc2 suppresses cell-surface expression of Lrp4, activation of MuSK, and postsynaptic specialization in muscle cells. These results suggest that Mesdc2 plays an essential role in NMJ formation by promoting Lrp4 maturation.


Asunto(s)
Chaperonas Moleculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Unión Neuromuscular/metabolismo , Receptores de LDL/metabolismo , Animales , Diferenciación Celular , Membrana Celular/metabolismo , Glicosilación , Células HEK293 , Humanos , Proteínas Relacionadas con Receptor de LDL , Ratones , Chaperonas Moleculares/genética , Fibras Musculares Esqueléticas/citología , Mioblastos/citología , Mioblastos/metabolismo , Procesamiento Proteico-Postraduccional , Transporte de Proteínas , ARN Interferente Pequeño , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de LDL/genética
13.
Oncol Rep ; 30(6): 2647-52, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24085263

RESUMEN

Several essential oils possess pharmacological effects. Among the various constituents of essential oils, 1, 8-cineole has been shown to possess pharmacological effects such as anti-bacterial and anti-inflammatory effects. The effect of 1, 8-cineole on human colorectal cancer cells, however, has not reported previously. In this study, we have investigated the anti-proliferative effect of 1, 8-cineole on human colon cancer cell lines HCT116 and RKO by WST-8 and BrdU assays. The cytotoxicity of 1, 8-cineole was investigated by LDH activity and TUNEL staining. The mechanism of apoptosis by 1, 8-cineole was determined by western blot analyses. In in vivo study, RKO cells were injected into the SCID mice and the effect of 1, 8-cineole was investigated. Specific induction of apoptosis, not necrosis, was observed in human colon cancer cell lines HCT116 and RKO by 1, 8-cineole. The treatment with 1, 8-cineole was associated with inactivation of survivin and Akt and activation of p38. These molecules induced cleaved PARP and caspase-3, finally causing apoptosis. In xenotransplanted SCID mice, the 1, 8-cineole group showed significantly inhibited tumor progression compared to the control group. These results indicated 1, 8-cineole suppressed human colorectal cancer proliferation by inducing apoptosis. Based on these studies 1, 8-cineole would be an effective strategy to treat colorectal cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinogénesis , Neoplasias del Colon/tratamiento farmacológico , Ciclohexanoles/administración & dosificación , Monoterpenos/administración & dosificación , Animales , Proliferación Celular/efectos de los fármacos , Neoplasias del Colon/patología , Ciclohexanoles/efectos adversos , Eucaliptol , Células HCT116 , Humanos , Ratones , Monoterpenos/efectos adversos , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Invest New Drugs ; 31(5): 1321-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23817973

RESUMEN

PURPOSE: Continuous treatment with FOLFOX therapy is associated with peripheral nerve toxicity, and to improve this inconvenient side effect various methods of administration are being investigated. A regimen of intermittent oxaliplatin administration by continuous infusion therapy, i.e., modified FOLFOX7 (mFOLFOX7) + bevacizumab, was designed with the goal of alleviating severe peripheral nerve disorders and hematological toxicity. A phase II clinical study was conducted to evaluate the efficacy and safety of this regimen. METHODS: Previously untreated patients were assigned to mFOLFOX7 (oxaliplatin 85 mg/m(2), levofolinate [l-LV] 200 mg/m(2), 5-fluorouracil [5-FU] 2400 mg/m(2)) + bevacizumab (5 mg/kg) administered every 2 weeks for 8 cycles, maintenance without oxaliplatin for 8 cycles, and reintroduction of mFOLFOX7 + bevacizumab for 8 cycles or until disease progression. Progression free survival (PFS) following the first dose (PFS 1) and following reintroduction of oxaliplatin (PFS 2) were used as indices for assessing the efficacy of intermittent administration. RESULTS: Fifty-two patients were enrolled, with median age of 64 years (range, 36-74). Median PFS 1 was 11.8 months (95 % confidence interval [CI], 9.5 to 13.7), median time to treatment failure was 10.3 months (95 % CI, 5.6 to 12.1), percentage of patients with neutropenia of grade 3 or higher was 7.8 %, and percentage with peripheral nerve disorders was 3.9 %. Response rate was 50 %, and 84.4 % of patients who started modified simplified LV5FU2 + bevacizumab were reintroduced to oxaliplatin. CONCLUSION: By excluding 5-FU bolus administration and administering bevacizumab continuously the mFOLFOX7 + bevacizumab regimen with preplanned withdrawal of oxaliplatin showed high tolerability and prevented severe peripheral neuropathy and neutropenia without reducing efficacy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Peritoneales/tratamiento farmacológico , Adulto , Anciano , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/efectos adversos , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Leucovorina/administración & dosificación , Leucovorina/efectos adversos , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/secundario , Metástasis Linfática , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Neoplasias Peritoneales/secundario , Resultado del Tratamiento
15.
Int J Oncol ; 43(2): 431-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23754252

RESUMEN

Fatty acid synthase is highly expressed in many types of human cancers. Cerulenin, a natural inhibitor of fatty acid synthase, induced apoptosis in the human colon cancer cell lines HCT116 and RKO. Oxaliplatin also induced cell death in these cell lines. Cerulenin treatment was associated with reduced levels of phosphorylated Akt, activation of p38 and induced caspase-3 cleavage and finally caused apoptosis. Oxaliplatin induced activation of the p53-p21 pathway and p38. In combination with cerulenin and oxaliplatin, activation of the p53-p21 pathway and p38 occurred in a smaller concentration and finally induced caspase-3 cleavage in a smaller concentration of cerulenin and oxaliplatin. In xenotransplanted SCID mice, the cerulenin + oxaliplatin group significantly inhibited tumor progression compared to the control, cerulenin and oxaliplatin groups. Based on these studies, inhibiting fatty acid synthase would be an effective strategy to treat unresectable colorectal cancer tumors in combination with oxaliplatin. Fatty acid synthase inhibitor would be one of the best counterparts of oxaliplatin, which reduces the dose and side-effects of oxaliplatin and would make it possible to endure the chemotherapy over a longer period.


Asunto(s)
Antineoplásicos/uso terapéutico , Cerulenina/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Inhibidores de la Síntesis de Ácidos Grasos/uso terapéutico , Compuestos Organoplatinos/uso terapéutico , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Cerulenina/farmacología , Ácido Graso Sintasas/antagonistas & inhibidores , Inhibidores de la Síntesis de Ácidos Grasos/farmacología , Células HCT116 , Humanos , Ratones , Trasplante de Neoplasias , Compuestos Organoplatinos/farmacología , Oxaliplatino
16.
Neuron ; 78(5): 839-54, 2013 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-23684785

RESUMEN

Highly topographic organization of neural circuits exists for the regulation of various brain functions in corticobasal ganglia circuits. Although neural circuit-specific refinement during synapse development is essential for the execution of particular neural functions, the molecular and cellular mechanisms for synapse refinement are largely unknown. Here, we show that protocadherin 17 (PCDH17), one of the nonclustered δ2-protocadherin family members, is enriched along corticobasal ganglia synapses in a zone-specific manner during synaptogenesis and regulates presynaptic assembly in these synapses. PCDH17 deficiency in mice causes facilitated presynaptic vesicle accumulation and enhanced synaptic transmission efficacy in corticobasal ganglia circuits. Furthermore, PCDH17(-/-) mice exhibit antidepressant-like phenotypes that are known to be regulated by corticobasal ganglia circuits. Our findings demonstrate a critical role for PCDH17 in the synaptic development of specific corticobasal ganglia circuits and suggest the involvement of PCDH17 in such circuits in depressive behaviors.


Asunto(s)
Ganglios Basales/citología , Cadherinas/fisiología , Corteza Cerebral/citología , Neuronas/fisiología , Terminales Presinápticos/fisiología , Sinapsis/genética , Estimulación Acústica , Animales , Animales Recién Nacidos , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Transformada , Condicionamiento Psicológico/fisiología , Cricetinae , Cricetulus , Homólogo 4 de la Proteína Discs Large , Conducta Exploratoria , Miedo/fisiología , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Guanilato-Quinasas/metabolismo , Suspensión Trasera/fisiología , Humanos , Técnicas In Vitro , Macaca mulatta , Masculino , Aprendizaje por Laberinto/fisiología , Potenciales de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Transgénicos , Microscopía Electrónica , Red Nerviosa/fisiología , Neuronas/metabolismo , Neuronas/ultraestructura , Técnicas de Placa-Clamp , Protocadherinas , Natación/fisiología , Sinapsis/metabolismo , Sinapsis/ultraestructura , Transmisión Sináptica/genética , Vesículas Sinápticas/metabolismo , Vesículas Sinápticas/ultraestructura , Proteínas de Transporte Vesicular de Glutamato/metabolismo
17.
Cancer Sci ; 104(3): 345-52, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23279575

RESUMEN

Overexpression of the ErbB2/HER2 receptor tyrosine kinase contributes to tumorigenesis. However, mechanisms regulating ErbB2 protein levels remain largely unclear. Here, we identified novel mechanisms of ErbB2 downregulation. ErbB2 constitutively binds to an adaptor protein FRS2ß. We found that FRS2ß bound to CD2AP and CIN85, which induces endosomal trafficking that targets lysosomes. FRS2ß colocalized with CIN85 in the cytoplasm. Expression of wild type FRS2ß but not its CIN85 non-binding mutant, downregulated the ErbB2 protein and inhibited anchorage-independent cell growth. Moreover, the E3 ubiquitin-protein ligase Cbl was contained within a complex of FRS2ß and CIN85. Knockdown of both CIN85 and CD2AP or of Cbl, or treatment with lysosomal degradation inhibitors diminished FRS2ß downregulation of ErbB2. In addition, knockdown of endogenous FRS2ß caused upregulation of ErbB2 in primary neural cells. Finally, immunohistochemical analysis showed that human breast cancer tissues that overexpress ErbB2 expressed low levels of FRS2ß. Thus, an FRS2ß-CIN85/CD2AP-Cbl axis for downregulation of ErbB2 may regulate ErbB2 protein levels in physiological and pathological settings. Molecular targeting drugs that can increase or stabilize the ErbB2-FRS2ß-CIN85/CD2AP-Cbl axis may have promise for the control of ErbB2-overexpressing tumors.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Fosfoproteínas/metabolismo , Receptor ErbB-2/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencias de Aminoácidos , Neoplasias de la Mama/metabolismo , Células Cultivadas , Regulación hacia Abajo , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Neuronas/metabolismo , Fosfoproteínas/genética , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Transducción de Señal
18.
J Biochem ; 152(5): 487-95, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22888118

RESUMEN

Through their ubiquitin ligase activity, Cbl-family proteins suppress signalling mediated by protein-tyrosine kinases (PTKs), but can also function as adaptor proteins to positively regulate signalling. The tyrosine kinase binding (TKB) domain of this family is critical for binding with tyrosine-phosphorylated target proteins. Here, we analysed the crystal structure of the TKB domain of Cbl-c/Cbl-3 (Cbl-c TKB), which is a distinct member of the mammalian Cbl-family. In comparison with Cbl TKB, Cbl-c TKB showed restricted structural flexibility upon phosphopeptide binding. A mutation in Cbl-c TKB augmenting this flexibility enhanced its binding to target phosphoproteins. These results suggest that proteins, post-translational modifications or mutations that alter structural flexibility of the TKB domain of Cbl-family proteins could regulate their binding to target phosphoproteins and thereby, affect PTK-mediated signalling.


Asunto(s)
Fosfopéptidos/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-cbl/química , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Sitios de Unión , Células Cultivadas , Cristalización , Células HEK293 , Humanos , Modelos Moleculares , Mutación , Fosfopéptidos/química , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas c-cbl/aislamiento & purificación
19.
Gan To Kagaku Ryoho ; 39(7): 1087-91, 2012 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-22790044

RESUMEN

UNLABELLED: We evaluated the efficacy and safety of neoadjuvant chemotherapy using modified OPTIMOX1 plus bevacizumab for advanced rectal cancer. PATIENTS AND METHODS: Nine cases with highly advanced rectal cancer for which curative surgery was potentially difficult were enrolled(clinical T4 in 7 cases, lateral node metastasis in 3 cases, M1 in 2 cases). RESULTS: The number of courses of modified OPTIMOX1(mFOLFOX6 and sLV5FU2, alternating administration)plus bevacizumab ranged from 1 to 21(median: 10). Surgical procedures consisted of internal sphincter resection(ISR)in 4 patients, ultra-low anterior resection(ULAR)in 2 patients, pelvic exenteration(TPE)in 2 patients, and Hartmann's procedure in 1 patient. Liver resection was conducted in 2 patients. RM1 was confirmed in 2 patients, but curative surgery was performed in the other patients. Histological efficacy of grade x/1a/1b/2were seen in the above 1/4/2/2 cases, respectively. Neurotoxicity associated with oxaliplatin was mild; no grade 3 neurotoxicity was noted. Recurrence has been confirmed in 5 patients at the median follow-up period of 650 days. CONCLUSION: It was suggested that modified OPTIMOX1 plus bevacizumab is effective and safe to administer as a neoadjuvant chemotherapy for curative resection or anus-preserving surgery in patients with highly advanced rectal cancer.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Neoadyuvante , Neoplasias del Recto/tratamiento farmacológico , Adulto , Anciano , Inhibidores de la Angiogénesis/administración & dosificación , Anticuerpos Monoclonales Humanizados/administración & dosificación , Bevacizumab , Femenino , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/uso terapéutico , Pronóstico , Neoplasias del Recto/diagnóstico , Neoplasias del Recto/cirugía , Recurrencia
20.
Neurosci Lett ; 516(2): 270-3, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22516462

RESUMEN

Previous studies found that the NMDA receptor-mediated signaling regulates thermal nociception, though the underlying molecular mechanism remains unclear. The GluN2B subunit of the NMDA receptor is tyrosine-phosphorylated, Tyr-1472 being the major phosphorylation site. In this study, we have found that homozygous knock-in mice that express a Tyr-1472-Phe mutant of GluN2B display defects in the nociceptive response in the hot plate test. Expression of the neurotensin receptor subtype 2 (NTSR2), which is relevant to the regulation of thermal nociception, is decreased in the amygdala of GluN2B Tyr-1472-Phe knock-in mice. In addition, NTSR2-mediated c-fos induction is impaired in the amygdala of these mice. These data suggest that Tyr-1472 phosphorylation on GluN2B is involved in thermal nociception through regulating the NTSR2 mRNA expression in the amygdala.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Nocicepción/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de Neurotensina/metabolismo , Animales , Regulación de la Expresión Génica , Técnicas de Sustitución del Gen , Calor , Ratones , Ratones Endogámicos C57BL , Fosforilación , ARN Mensajero/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de N-Metil-D-Aspartato/genética , Tirosina/metabolismo
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