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1.
Epigenomes ; 8(2)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38920623

RESUMEN

The development of the nervous system is regulated by numerous intracellular molecules and cellular signals that interact temporally and spatially with the extracellular microenvironment. The three major cell types in the brain, i.e., neurons and two types of glial cells (astrocytes and oligodendrocytes), are generated from common multipotent neural stem cells (NSCs) throughout life. However, NSCs do not have this multipotentiality from the beginning. During cortical development, NSCs sequentially obtain abilities to differentiate into neurons and glial cells in response to combinations of spatiotemporally modulated cell-intrinsic epigenetic alterations and extrinsic factors. After the completion of brain development, a limited population of NSCs remains in the adult brain and continues to produce neurons (adult neurogenesis), thus contributing to learning and memory. Many biological aspects of brain development and adult neurogenesis are regulated by epigenetic changes via behavioral control of NSCs. Epigenetic dysregulation has also been implicated in the pathogenesis of various brain diseases. Here, we present recent advances in the epigenetic regulation of NSC behavior and its dysregulation in brain disorders.

2.
Front Neurosci ; 17: 1150283, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36937666

RESUMEN

Epilepsy is a chronic neurological disorder characterized by hypersynchronous spontaneous recurrent seizures, and affects approximately 50 million people worldwide. Cumulative evidence has revealed that epileptogenic insult temporarily increases neurogenesis in the hippocampus; however, a fraction of the newly generated neurons are integrated abnormally into the existing neural circuits. The abnormal neurogenesis, including ectopic localization of newborn neurons in the hilus, formation of abnormal basal dendrites, and disorganization of the apical dendrites, rewires hippocampal neural networks and leads to the development of spontaneous seizures. The central roles of hilar ectopic granule cells in regulating hippocampal excitability have been suggested. In this review, we introduce recent findings about the migration of newborn granule cells to the dentate hilus after seizures and the roles of seizure-induced ectopic granule cells in the epileptic brain. In addition, we delineate possible intrinsic and extrinsic mechanisms underlying this abnormality. Finally, we suggest that the regulation of seizure-induced ectopic cells can be a promising target for epilepsy therapy and provide perspectives on future research directions.

3.
JCI Insight ; 6(22)2021 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-34806649

RESUMEN

Spiral ganglion neurons (SGNs) are primary auditory neurons in the spiral ganglion that transmit sound information from the inner ear to the brain and play an important role in hearing. Impairment of SGNs causes sensorineural hearing loss (SNHL), and it has been thought until now that SGNs cannot be regenerated once lost. Furthermore, no fundamental therapeutic strategy for SNHL has been established other than inserting devices such as hearing aids and cochlear implants. Here we show that the mouse spiral ganglion contains cells that are able to proliferate and indeed differentiate into neurons in response to injury. We suggest that SRY-box transcription factor 2/SRY-box transcription factor 10-double-positive (Sox2/Sox10-double-positive) Schwann cells sequentially started to proliferate, lost Sox10 expression, and became neurons, although the number of new neurons generated spontaneously was very small. To increase the abundance of new neurons, we treated mice with 2 growth factors in combination with valproic acid, which is known to promote neuronal differentiation and survival. This treatment resulted in a dramatic increase in the number of SGNs, accompanied by a partial recovery of the hearing loss induced by injury. Taken together, our findings offer a step toward developing strategies for treatment of SNHL.


Asunto(s)
Pérdida Auditiva/tratamiento farmacológico , Neuronas/metabolismo , Ácido Valproico/uso terapéutico , Animales , Pérdida Auditiva/patología , Humanos , Ratones , Regeneración , Ácido Valproico/farmacología
4.
J Reprod Dev ; 67(6): 369-379, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-34615840

RESUMEN

Post-mitotic neurons do exhibit DNA methylation changes, contrary to the longstanding belief that the epigenetic pattern in terminally differentiated cells is essentially unchanged. While the mechanism and physiological significance of DNA demethylation in neurons have been extensively elucidated, the occurrence of de novo DNA methylation and its impacts have been much less investigated. In the present study, we showed that neuronal activation induces de novo DNA methylation at enhancer regions, which can repress target genes in primary cultured hippocampal neurons. The functional significance of this de novo DNA methylation was underpinned by the demonstration that inhibition of DNA methyltransferase (DNMT) activity decreased neuronal activity-induced excitatory synaptogenesis. Overexpression of WW and C2 domain-containing 1 (Wwc1), a representative target gene of de novo DNA methylation, could phenocopy this DNMT inhibition-induced decrease in synaptogenesis. We found that both DNMT1 and DNMT3a were required for neuronal activity-induced de novo DNA methylation of the Wwc1 enhancer. Taken together, we concluded that neuronal activity-induced de novo DNA methylation that affects gene expression has an impact on neuronal physiology that is comparable to that of DNA demethylation. Since the different requirements of DNMTs for germ cell and embryonic development are known, our findings also have considerable implications for future studies on epigenomics in the field of reproductive biology.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas , Metilación de ADN , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN Metiltransferasa 3A , Neuronas/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos
5.
Neurosci Res ; 173: 22-33, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34058264

RESUMEN

Gene expression programs and concomitant chromatin regulation change dramatically during the maturation of postmitotic neurons. Subnuclear positioning of gene loci is relevant to transcriptional regulation. However, little is known about subnuclear genome positioning in neuronal maturation. Using cultured murine hippocampal neurons, we found genomic locus 14qD2 to be enriched with genes that are upregulated during neuronal maturation. Reportedly, the locus is homologous to human 8p21.3, which has been extensively studied in neuropsychiatry and neurodegenerative diseases. Mapping of the 14qD2 locus in the nucleus revealed that it was relocated from the nuclear periphery to the interior. Moreover, we found a concomitant decrease in lamin B1 expression. Overexpression of lamin B1 in neurons using a lentiviral vector prevented the relocation of the 14qD2 locus and repressed the transcription of the Egr3 gene on this locus. Taken together, our results suggest that reduced lamin B1 expression during the maturation of neurons is important for appropriate subnuclear positioning of the genome and transcriptional programs.


Asunto(s)
Lamina Tipo B , Neuronas , Animales , Núcleo Celular , Humanos , Lamina Tipo B/genética , Ratones , Neurogénesis
6.
Cell Rep ; 35(7): 109124, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-34010654

RESUMEN

Rett syndrome (RTT) is a severe neurological disorder, with impaired brain development caused by mutations in MECP2; however, the underlying mechanism remains elusive. We know from previous work that MeCP2 facilitates the processing of a specific microRNA, miR-199a, by associating with the Drosha complex to regulate neuronal functions. Here, we show that the MeCP2/miR-199a axis regulates neural stem/precursor cell (NS/PC) differentiation. A shift occurs from neuronal to astrocytic differentiation of MeCP2- and miR-199a-deficient NS/PCs due to the upregulation of a miR-199a target, Smad1, a downstream transcription factor of bone morphogenetic protein (BMP) signaling. Moreover, miR-199a expression and treatment with BMP inhibitors rectify the differentiation of RTT patient-derived NS/PCs and development of brain organoids, respectively, suggesting that facilitation of BMP signaling accounts for the impaired RTT brain development. Our study illuminates the molecular pathology of RTT and reveals the MeCP2/miR-199a/Smad1 axis as a potential therapeutic target for RTT.


Asunto(s)
Receptores de Proteínas Morfogenéticas Óseas/metabolismo , Proteína 2 de Unión a Metil-CpG/metabolismo , Células-Madre Neurales/metabolismo , Síndrome de Rett/genética , Animales , Diferenciación Celular , Modelos Animales de Enfermedad , Humanos , Ratones , Transducción de Señal
7.
Pediatr Neonatol ; 61(1): 100-105, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31473126

RESUMEN

BACKGROUND: Phototherapy with radiation of 460-490 nm wavelengths provides the most potent therapeutic effect for neonatal jaundice. However, the efficacy of phototherapy has been estimated using single-wavelength detectors with sensitivity at approximately 460 nm. Cyclobilirubin formation capacity (CFC), which comprises the sum of the irradiance values from three wavelengths multiplied by their specific coefficients, has been proposed as an alternative marker to evaluate the efficacy of phototherapy. This study aimed to test whether two types of phototherapy devices with distinct spectral characteristics provide similar therapeutic effects on adjustment of device-to-patient distances to deliver similar CFCs. METHODS: Using a three-wavelength spectroradiometer, CFCs and footprints of the light-emitting diode and fluorescent tube devices were assessed. Having determined the device-specific distances that ensured similar CFCs, 32 newborn infants, requiring phototherapy for hyperbilirubinemia, were randomized into the light-emitting diode and fluorescent tube groups. The total serum bilirubin levels before and after phototherapy were assessed. RESULTS: The light-emitting diode and fluorescent tube devices had comparable CFCs at distances of 60 and 50 cm, respectively. Phototherapy reduced the total serum bilirubin levels from 18.1 to 14.6 mg/dL and from 19.1 to 15.1 mg/dL in the light-emitting diode and fluorescent tube groups, respectively. The two groups did not differ significantly with respect to the patients' clinical backgrounds, serum bilirubin levels, or changes before and after phototherapy. CONCLUSION: At similar CFCs, the two phototherapy devices reduced the total serum bilirubin levels by comparable amounts. Hence, determining CFCs may help predict phototherapy efficacy. This may ensure better safety and greater efficacy of the treatment for newborn infants.


Asunto(s)
Hiperbilirrubinemia Neonatal/terapia , Fototerapia/normas , Bilirrubina/análogos & derivados , Bilirrubina/biosíntesis , Bilirrubina/sangre , Femenino , Humanos , Hiperbilirrubinemia Neonatal/sangre , Recién Nacido , Masculino , Fototerapia/métodos
8.
SAGE Open Med Case Rep ; 7: 2050313X19838170, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30911391

RESUMEN

Acquired bronchial stenosis is rare in children, usually caused by infection or traumatic granuloma due to chronic intubation. A case of severe acquired left bronchial stenosis successfully treated by conservative management for gastroesophageal reflux and atelectasis is reported. A male infant born at 24 weeks' gestation, weighing 461 g, presented with massive atelectasis of the left lower lobe and severe left bronchial stenosis, based on chest computed tomography performed for the evaluation of respiratory failure at the age of 8 months. He responded well to the placement of a duodenal tube for gastroesophageal reflux and chest physiotherapy, reducing the symptoms of atelectasis and successfully managing the left bronchial stenosis. Acquired bronchial stenosis could be caused by bronchial shift due to atelectasis, and it can be cured by conservative management. In cases of acquired bronchial stenosis with massive atelectasis, it is important to consider atelectasis as a potential cause of the acquired bronchial stenosis.

9.
Neurosci Res ; 141: 63-70, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29604317

RESUMEN

Spinal cord injury (SCI) is a devastating neurologic disorder that often leads to permanent disability, and there is no effective treatment for it. High mobility group box-1 (HMGB1) is a damage-associated molecular protein that triggers sterile inflammation upon injuries. We have previously shown that two administrations of neutralizing monoclonal antibody (mAb) against HMGB1 (immediately after (0 h) and 6 h after) SCI dramatically improves functional recovery after SCI in mice. However, when considering clinical application, 0 h after SCI is not practical. Therefore, in this study, we examined the therapeutic time window of the mAb administration. Injection at 3 h after SCI significantly improved the functional recovery comparably to injection immediately after SCI, while injection at 6 h was less effective, and injection at 9 or 12 h had no therapeutic effect. We also found beneficial effects of injection at 3 h after injury on blood-spinal cord barrier maintenance, inflammatory-related gene expression and preservation of the damaged spinal cord tissue. Taken together, our results suggest that a single administration of anti-HMGB1 mAb within a proper time window could be a novel and potential therapeutic strategy for SCI.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Proteína HMGB1/administración & dosificación , Traumatismos de la Médula Espinal/tratamiento farmacológico , Médula Espinal/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Femenino , Proteína HMGB1/inmunología , Ratones Endogámicos C57BL , Mielitis/etiología , Mielitis/prevención & control , Recuperación de la Función , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/inmunología
10.
Neuroscience ; 398: 193-205, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30528855

RESUMEN

Reactive oxygen species (ROS) modulate the growth of neural stem/precursor cells (NS/PCs) and participate in hippocampus-associated learning and memory. However, the origin of these regulatory ROS in NS/PCs is not fully understood. In the present study, we found that Nox4, a ROS-producing NADPH oxidase family protein, is expressed in primary cultured NS/PCs and in those of the adult mouse brain. Nox inhibitors VAS 2870 and GKT137831 or Nox4 deletion attenuated bFGF-induced proliferation of cultured NS/PCs, while lentivirus-mediated Nox4 overexpression increased the production of H2O2, the phosphorylation of Akt, and the proliferation of cultured NS/PCs. Nox4 did not significantly affect the potential of cultured NS/PCs to differentiate into neurons or astrocytes. The histological and functional development of the hippocampus appeared normal in Nox4-/- mice. Although pathological and functional damages in the hippocampus induced by the neurotoxin trimethyltin were not significantly different between wild-type and Nox4-/- mice, the post-injury reactive proliferation of NS/PCs and neurogenesis in the subgranular zone (SGZ) of the dentate gyrus were significantly impaired in Nox4-/- animals. Restoration from the trimethyltin-induced impairment in recognition and spatial working memory was also significantly attenuated in Nox4-/- mice. Collectively, our findings suggest that Nox4 participates in NS/PC proliferation and neurogenesis in the hippocampus following injury, thereby helping to restore memory function.


Asunto(s)
Proliferación Celular/fisiología , Hipocampo/metabolismo , NADPH Oxidasa 4/metabolismo , Células-Madre Neurales/metabolismo , Neurogénesis/fisiología , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Hipocampo/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Aprendizaje/efectos de los fármacos , Aprendizaje/fisiología , Masculino , Memoria/efectos de los fármacos , Memoria/fisiología , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 2/metabolismo , NADPH Oxidasa 4/genética , Células-Madre Neurales/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neurotoxinas , Compuestos de Trimetilestaño
11.
J Neurosci ; 38(20): 4791-4810, 2018 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-29695415

RESUMEN

Functional neuronal connectivity requires proper neuronal morphogenesis and its dysregulation causes neurodevelopmental diseases. Transforming growth factor-ß (TGF-ß) family cytokines play pivotal roles in development, but little is known about their contribution to morphological development of neurons. Here we show that the Smad-dependent canonical signaling of TGF-ß family cytokines negatively regulates neuronal morphogenesis during brain development. Mechanistically, activated Smads form a complex with transcriptional repressor TG-interacting factor (TGIF), and downregulate the expression of a neuronal polarity regulator, collapsin response mediator protein 2. We also demonstrate that TGF-ß family signaling inhibits neurite elongation of human induced pluripotent stem cell-derived neurons. Furthermore, the expression of TGF-ß receptor 1, Smad4, or TGIF, which have mutations found in patients with neurodevelopmental disorders, disrupted neuronal morphogenesis in both mouse (male and female) and human (female) neurons. Together, these findings suggest that the regulation of neuronal morphogenesis by an evolutionarily conserved function of TGF-ß signaling is involved in the pathogenesis of neurodevelopmental diseases.SIGNIFICANCE STATEMENT Canonical transforming growth factor-ß (TGF-ß) signaling plays a crucial role in multiple organ development, including brain, and mutations in components of the signaling pathway associated with several human developmental disorders. In this study, we found that Smads/TG-interacting factor-dependent canonical TGF-ß signaling regulates neuronal morphogenesis through the suppression of collapsin response mediator protein-2 (CRMP2) expression during brain development, and that function of this signaling is evolutionarily conserved in the mammalian brain. Mutations in canonical TGF-ß signaling factors identified in patients with neurodevelopmental disorders disrupt the morphological development of neurons. Thus, our results suggest that proper control of TGF-ß/Smads/CRMP2 signaling pathways is critical for the precise execution of neuronal morphogenesis, whose impairment eventually results in neurodevelopmental disorders.


Asunto(s)
Proteínas de Homeodominio/fisiología , Péptidos y Proteínas de Señalización Intercelular/fisiología , Morfogénesis/fisiología , Proteínas del Tejido Nervioso/fisiología , Neuronas/fisiología , Proteínas Represoras/fisiología , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta/fisiología , Animales , Axones/efectos de los fármacos , Células Cultivadas , Dendritas/efectos de los fármacos , Femenino , Hipocampo/citología , Hipocampo/efectos de los fármacos , Proteínas de Homeodominio/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Masculino , Ratones , Mutación/genética , Proteínas del Tejido Nervioso/genética , Enfermedades del Sistema Nervioso/genética , Células-Madre Neurales , Embarazo , Proteínas Represoras/genética , Proteína Smad4/genética , Proteína Smad4/fisiología
12.
Radiat Oncol ; 12(1): 112, 2017 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-28673362

RESUMEN

BACKGROUND: The aim of this retrospective observational study was to evaluate toxicities, overall survival, and locoregional control in elderly oral squamous cell carcinoma patients who had undergone retrograde intra-arterial chemotherapy combined with radiotherapy. METHODS: Thirty-one elderly patients over 80 years old with oral squamous cell carcinoma were enrolled in present study. The treatment schedule consisted of intra- arterial chemotherapy (docetaxel, total 60 mg/m2; cisplatin, total 150 mg/m2) and daily concurrent radiotherapy (total, 60 Gy) for 6 weeks. RESULTS: The median patient age was 82.5 years old (range, 80-88 years). Of the 31 patients, six (19%) had stage II, 6 (19%) had stage III, 17 (55%) had stage IVA, and 2 (6%) had stage IVB. The median follow-up period for all patients was 37 months (range, 7-86 months). The 3-year overall survival and locoregional control rates were 78% and 81%, respectively. The major acute grade 3 adverse events were oral mucositis in 22 (71%) patients, neutropenia in 16 (52%), and dermatitis in 11 (35%). With respect to late toxicities, 1 patient (3%) developed grade 3 osteoradionecrosis of the jaw. No grade 4 or higher toxicities were observed during the treatment and follow-up periods. CONCLUSIONS: Retrograde intra-arterial chemotherapy combined with radiotherapy was effective in improving overall survival and locoregional control even for elderly patients.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Cisplatino/uso terapéutico , Neoplasias de la Boca/terapia , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias de la Boca/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
13.
Stem Cell Reports ; 8(6): 1743-1756, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28591654

RESUMEN

Human neural precursor cells (hNPCs) derived from pluripotent stem cells display a high propensity for neuronal differentiation, but they require long-term culturing to differentiate efficiently into astrocytes. The mechanisms underlying this biased fate specification of hNPCs remain elusive. Here, we show that hypoxia confers astrocytic differentiation potential on hNPCs through epigenetic gene regulation, and that this was achieved by cooperation between hypoxia-inducible factor 1α and Notch signaling, accompanied by a reduction of DNA methylation level in the promoter region of a typical astrocyte-specific gene, Glial fibrillary acidic protein. Furthermore, we found that this hypoxic culture condition could be applied to rapid generation of astrocytes from Rett syndrome patient-derived hNPCs, and that these astrocytes impaired neuronal development. Thus, our findings shed further light on the molecular mechanisms regulating hNPC differentiation and provide attractive tools for the development of therapeutic strategies for treating astrocyte-mediated neurological disorders.


Asunto(s)
Astrocitos/citología , Diferenciación Celular , Hipoxia de la Célula , Epigenómica , Células-Madre Neurales/citología , Células Madre Pluripotentes/citología , Astrocitos/metabolismo , Sitios de Unión , Línea Celular , Islas de CpG , Metilación de ADN , Proteína Ácida Fibrilar de la Glía/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Células-Madre Neurales/metabolismo , Células Madre Pluripotentes/metabolismo , Regiones Promotoras Genéticas , Receptores Notch/metabolismo , Síndrome de Rett/metabolismo , Síndrome de Rett/patología , Factor de Transcripción STAT3/química , Factor de Transcripción STAT3/metabolismo , Transducción de Señal
14.
Artículo en Inglés | MEDLINE | ID: mdl-28434836

RESUMEN

OBJECTIVE: To evaluate the therapeutic results and control of occult neck metastasis in patients with T2-4N0 oral tongue squamous cell carcinoma treated with retrograde superselective intra-arterial chemotherapy and daily concurrent radiotherapy. STUDY DESIGN: Forty-two patients with T2-4N0 tongue cancer (17 with late T2; 13 with T3; and 12 with T4a disease, M0) were treated with intra-arterial chemoradiotherapy. Treatment consisted of retrograde superselective intra-arterial chemotherapy (docetaxel 50-70 mg/m2, cisplatin 125-175 mg/m2) and daily concurrent radiotherapy (50-70 Gy) for 5-7 weeks. RESULTS: The median follow-up for all patients was 46.5 months (range, 8-105 months). Primary-site complete response was achieved in 42 of 42 cases (100%). Three-year overall survival, progression-free survival, and local control rates were 85.0%, 77.8%, and 91.7%, respectively. Delayed neck metastasis was detected in 5 of 42 cases (11.9%). Grade 3 or 4 toxic changes included oral mucositis in 92.9%, neutropenia in 21.4%, and thrombocytopenia in 4.8%. Grade 3 toxicities included anemia in 16.7%, radiation dermatitis in 9.5%, nausea in 4.8%, and fever in 2.4%. CONCLUSIONS: Retrograde superselective intra-arterial chemotherapy for T2-4N0 tongue cancer provided good overall survival and local control rates and was effective for occult neck metastasis.


Asunto(s)
Neoplasias de Cabeza y Cuello/secundario , Neoplasias de la Lengua/patología , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cisplatino/administración & dosificación , Terapia Combinada , Diagnóstico por Imagen , Docetaxel , Femenino , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Infusiones Intraarteriales , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Inducción de Remisión , Tasa de Supervivencia , Taxoides/administración & dosificación , Neoplasias de la Lengua/diagnóstico por imagen , Neoplasias de la Lengua/tratamiento farmacológico , Neoplasias de la Lengua/radioterapia , Resultado del Tratamiento
15.
Indian J Otolaryngol Head Neck Surg ; 69(1): 6-10, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28239570

RESUMEN

Squamous cell carcinoma (SCC) of the tongue is the most common oral cancer. Most cases occur on the lateral border of the tongue and only very rarely on the dorsum. We retrospectively investigated the incidence of SCC of the tongue dorsum in our department between April 2006 and March 2015. Of the 368 patients with tongue cancer, only 3 had SCC of the tongue dorsum (incidence, 0.8 %). All patients with advanced cancer of the tongue dorsum underwent superselective intra-arterial chemoradiotherapy for organ preservation. We discuss the present findings in relation to past case reports and series in the English language literature as well as discuss treatments for SCC of the tongue dorsum.

16.
Nat Biotechnol ; 34(10): 1060-1065, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27571369

RESUMEN

Despite the importance of DNA methylation in health and disease, technologies to readily manipulate methylation of specific sequences for functional analysis and therapeutic purposes are lacking. Here we adapt the previously described dCas9-SunTag for efficient, targeted demethylation of specific DNA loci. The original SunTag consists of ten copies of the GCN4 peptide separated by 5-amino-acid linkers. To achieve efficient recruitment of an anti-GCN4 scFv fused to the ten-eleven (TET) 1 hydroxylase, which induces demethylation, we changed the linker length to 22 amino acids. The system attains demethylation efficiencies >50% in seven out of nine loci tested. Four of these seven loci showed demethylation of >90%. We demonstrate targeted demethylation of CpGs in regulatory regions and demethylation-dependent 1.7- to 50-fold upregulation of associated genes both in cell culture (embryonic stem cells, cancer cell lines, primary neural precursor cells) and in vivo in mouse fetuses.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas Asociadas a CRISPR/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Metilación de ADN/genética , Oxigenasas de Función Mixta/genética , Proteínas Proto-Oncogénicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Anticuerpos de Cadena Única/genética , Animales , Catálisis , Islas de CpG/genética , Marcación de Gen/métodos , Ingeniería Genética/métodos , Ratones , Dominios Proteicos
17.
Sci Rep ; 6: 27548, 2016 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-27271009

RESUMEN

Despite the fact that radiation is one of the standard therapies in the treatment of patients with oral cancer, tumours can recur even in the early stages of the disease, negatively impacting prognosis and quality of life. We previously found that CD11b(+) bone marrow-derived cells (BMDCs) were recruited into human glioblastoma multiforme (GBM), leading to re-organization of the vasculature and tumour regrowth. However, it is not yet known how these cells contribute to tumour vascularization. In the present study, we investigated the role of infiltrating CD11b(+) myeloid cells in the vascularization and recurrence of oral squamous cell carcinoma (OSCC). In a xenograft mouse model, local irradiation caused vascular damage and hypoxia in the tumour and increased infiltration of CD11b(+) myeloid cells. These infiltrating cells showed characteristics of M2 macrophages (M2Mφs) and are associated with the promotion of vascularization. M2Mφs promoted tumour progression in recurrence after irradiation compared to non-irradiated tumours. In addition, we found that CD11b(+) myeloid cells, as well as CD206(+) M2Mφs, are increased during recurrence after radiotherapy in human OSCC specimens. Our findings may lead to the development of potential clinical biomarkers or treatment targets in irradiated OSCC patients.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de la Boca/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Neovascularización Patológica/radioterapia , Animales , Biomarcadores de Tumor/genética , Antígeno CD11b/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Hipoxia de la Célula/efectos de la radiación , Línea Celular Tumoral , Humanos , Macrófagos/patología , Ratones , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Células Mieloides/patología , Células Mieloides/efectos de la radiación , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Recurrencia , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Biochim Biophys Acta ; 1860(8): 1753-63, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27068854

RESUMEN

We previously demonstrated that focal adhesion kinase (FAK), p130Cas and paxillin are crucially involved in the enhanced malignant properties under expression of ganglioside GD3 in melanoma cells. Therefore, molecules existing in the GD3-mediated signaling pathway could be considered as suitable targets for therapeutic intervention in malignant melanoma. The aim of this study was to determine whether blockade of p130Cas and/or paxillin by RNAi suppresses melanoma growth. We found a suitable dose (40 µM siRNA, 25 µl/tumor) of the siRNA to suppress p130Cas in the xenografts generated in nu/nu mice. Based on these results, we performed intratumoral (i.t.) treatment with anti-p130Cas and/or anti-paxillin siRNAs mixed with atelocollagen as a drug delivery system in a xenograft tumor of a human melanoma cell line, SK-MEL-28. Mixture of atelocollagen (1.75%) and an siRNA (500 or 1000 pmol/tumor) was injected into the tumors every 3 days after the first injection. An siRNA against human p130Cas markedly suppressed tumor growth of the xenograft in a dose-dependent manner, whereas siRNA against human paxillin slightly inhibited the tumor growth. A control siRNA against firefly luciferase showed no effect. To our surprise, siRNA against human p130Cas (500 or 1000 pmol/tumor) combined with siRNA against human paxillin dramatically suppressed tumor growth. In agreement with the tumor suppression effects of the anti-p130Cas siRNA, reduction in Ki-67 positive cell number as well as in p130Cas expression was demonstrated by immunohistostaining. These results suggested that blockade of GD3-mediated growth signaling pathways by siRNAs might be a novel and promising therapeutic strategy against malignant melanomas, provided signaling molecules such as p130Cas and paxillin are significantly expressed in individual cases. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.


Asunto(s)
Proteína Sustrato Asociada a CrK , Gangliósidos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Melanoma , Proteínas de Neoplasias , Paxillin , ARN Interferente Pequeño , Animales , Línea Celular Tumoral , Proteína Sustrato Asociada a CrK/antagonistas & inhibidores , Proteína Sustrato Asociada a CrK/biosíntesis , Proteína Sustrato Asociada a CrK/genética , Gangliósidos/biosíntesis , Gangliósidos/genética , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Ratones , Ratones Desnudos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Paxillin/antagonistas & inhibidores , Paxillin/biosíntesis , Paxillin/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Biol Chem ; 291(26): 13891-904, 2016 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-27129236

RESUMEN

Proper dendritic elaboration of neurons is critical for the formation of functional circuits during brain development. Defects in dendrite morphogenesis are associated with neuropsychiatric disorders, and microRNAs are emerging as regulators of aspects of neuronal maturation such as axonal and dendritic growth, spine formation, and synaptogenesis. Here, we show that miR-214 plays a pivotal role in the regulation of dendritic development. Overexpression of miR-214 increased dendrite size and complexity, whereas blocking of endogenous miR-214-3p, a mature form of miR-214, inhibited dendritic morphogenesis. We also found that miR-214-3p targets quaking (Qki), which is implicated in psychiatric diseases such as schizophrenia, through conserved target sites located in the 3'-untranslated region of Qki mRNA, thereby down-regulating Qki protein levels. Overexpression and knockdown of Qki impaired and enhanced dendritic formation, respectively. Moreover, overexpression of Qki abolished the dendritic growth induced by miR-214 overexpression. Taken together, our findings reveal a crucial role for the miR-214-Qki pathway in the regulation of neuronal dendritic development.


Asunto(s)
Dendritas/metabolismo , Regulación hacia Abajo , MicroARNs/metabolismo , Proteínas de Unión al ARN/biosíntesis , Sinapsis/metabolismo , Animales , Axones/metabolismo , Dendritas/genética , Ratones , MicroARNs/genética , Proteínas de Unión al ARN/genética , Esquizofrenia/genética , Esquizofrenia/metabolismo , Sinapsis/genética
20.
Sci Rep ; 6: 24629, 2016 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-27103308

RESUMEN

We previously investigated the utility of µ-oxo N,N'- bis(salicylidene)ethylenediamine iron (Fe(Salen)) nanoparticles as a new anti-cancer agent for magnet-guided delivery with anti-cancer activity. Fe(Salen) nanoparticles should rapidly heat up in an alternating magnetic field (AMF), and we hypothesized that these single-drug nanoparticles would be effective for combined hyperthermia-chemotherapy. Conventional hyperthermic particles are usually made of iron oxide, and thus cannot exhibit anti-cancer activity in the absence of an AMF. We found that Fe(Salen) nanoparticles induced apoptosis in cultured cancer cells, and that AMF exposure enhanced the apoptotic effect. Therefore, we evaluated the combined three-fold strategy, i.e., chemotherapy with Fe(Salen) nanoparticles, magnetically guided delivery of the nanoparticles to the tumor, and AMF-induced heating of the nanoparticles to induce local hyperthermia, in a rabbit model of tongue cancer. Intravenous administration of Fe(Salen) nanoparticles per se inhibited tumor growth before the other two modalities were applied. This inhibition was enhanced when a magnet was used to accumulate Fe(Salen) nanoparticles at the tongue. When an AMF was further applied (magnet-guided chemotherapy plus hyperthermia), the tumor masses were dramatically reduced. These results indicate that our strategy of combined hyperthermia-chemotherapy using Fe(Salen) nanoparticles specifically delivered with magnetic guidance represents a powerful new approach for cancer treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Quimioterapia/métodos , Hipertermia Inducida/métodos , Compuestos de Hierro/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias de la Lengua/tratamiento farmacológico , Animales , Apoptosis , Línea Celular Tumoral , Modelos Animales de Enfermedad , Conejos , Resultado del Tratamiento
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