RESUMEN
During development, neural progenitors are in proliferative and immature states; however, the molecular machinery that cooperatively controls both states remains elusive. Here, we report that cyclin D1 (CCND1) directly regulates both proliferative and immature states of cerebellar granule cell progenitors (GCPs). CCND1 not only accelerates cell cycle but also upregulates ATOH1 protein, an essential transcription factor that maintains GCPs in an immature state. In cooperation with CDK4, CCND1 directly phosphorylates S309 of ATOH1, which inhibits additional phosphorylation at S328 and consequently prevents S328 phosphorylation-dependent ATOH1 degradation. Additionally, PROX1 downregulates Ccnd1 expression by histone deacetylation of Ccnd1 promoter in GCPs, leading to cell cycle exit and differentiation. Moreover, WNT signaling upregulates PROX1 expression in GCPs. These findings suggest that WNT-PROX1-CCND1-ATOH1 signaling cascade cooperatively controls proliferative and immature states of GCPs. We revealed that the expression and phosphorylation levels of these molecules dynamically change during cerebellar development, which are suggested to determine appropriate differentiation rates from GCPs to GCs at distinct developmental stages. This study contributes to understanding the regulatory mechanism of GCPs as well as neural progenitors.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cerebelo/crecimiento & desarrollo , Cerebelo/metabolismo , Ciclina D1/metabolismo , Gránulos Citoplasmáticos/metabolismo , Fosforilación/fisiología , Células Madre/metabolismo , Animales , Ciclo Celular/genética , Diferenciación Celular/fisiología , División Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Proteínas Hedgehog/metabolismo , Ratones , Neurogénesis/fisiología , Transducción de Señal/fisiología , Factores de TranscripciónRESUMEN
GABAergic interneurons are key elements in neural coding, but the mechanisms that assemble inhibitory circuits remain unclear. In the spinal cord, the transfer of sensory signals to motor neurons is filtered by GABAergic interneurons that act presynaptically to inhibit sensory transmitter release and postsynaptically to inhibit motor neuron excitability. We show here that the connectivity and synaptic differentiation of GABAergic interneurons that mediate presynaptic inhibition is directed by their sensory targets. In the absence of sensory terminals these GABAergic neurons shun other available targets, fail to undergo presynaptic differentiation, and withdraw axons from the ventral spinal cord. A sensory-specific source of brain derived neurotrophic factor induces synaptic expression of the GABA synthetic enzyme GAD65--a defining biochemical feature of this set of interneurons. The organization of a GABAergic circuit that mediates presynaptic inhibition in the mammalian CNS is therefore controlled by a stringent program of sensory recognition and signaling.
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Interneuronas/fisiología , Médula Espinal/fisiología , Ácido gamma-Aminobutírico/fisiología , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Glutamato Descarboxilasa , Ratones , Neuronas Motoras/fisiología , Terminales Presinápticos , Propiocepción , Células Receptoras Sensoriales/fisiología , Médula Espinal/citologíaRESUMEN
BACKGROUND: Borderline resectable pancreatic cancer (BRPC) is a category of pancreatic cancer that is anatomically widely spread, and curative resection is uncommon with upfront surgery. Intensity-modulated radiation therapy (IMRT) is a form of radiation therapy that delivers precise radiation to a tumor while minimizing the dose to surrounding normal tissues. Here, we conducted a phase 2 study to estimate the curability and efficacy of neoadjuvant chemoradiotherapy using IMRT (NACIMRT) for patients with BRPC with arterial abutment (BRPC-A). METHODS: A total of 49 BRPC-A patients were enrolled in this study and were treated at our hospital according to the study protocol between June 2013 and March 2021. The primary endpoint was microscopically margin-negative resection (R0) rates and we subsequently analyzed safety, histological effect of the treatment as well as survivals among patients with NACIMRT. RESULTS: Twenty-nine patients (59.2%) received pancreatectomy after NACIMRT. The R0 rate in resection patients was 93.1% and that in the whole cohort was 55.1%. No mortality was encountered. Local therapeutic effects as assessed by Evans classification showed good therapeutic effect (Grade 1, 3.4%; Grade 2a, 31.0%; Grade 2b, 48.3%; Grade 3, 3.4%; Grade 4, 3.4%). Median disease-free survival was 15.5 months. Median overall survival in the whole cohort was 35.1 months. The only independent prognostic pre-NACIMRT factor identified was serum carbohydrate antigen 19-9 (CA19-9) > 400 U/ml before NACIMRT. CONCLUSIONS: NACIMRT showed preferable outcome without significant operative morbidity for BRPC-A patients. NACIMRT contributes to good local tumor control, but a high initial serum CA19-9 implies poor prognosis even after neoadjuvant treatment. TRIAL REGISTRATION: UMIN-CTR Clinical Trial: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000011776 Registration number: UMIN000010113. Date of first registration: 01/03/2013.
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Terapia Neoadyuvante , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/terapia , Radioterapia de Intensidad Modulada , Anciano , Antígenos de Carbohidratos Asociados a Tumores/sangre , Arterias , Femenino , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Pancreatectomía , Estudios Prospectivos , Resultado del TratamientoRESUMEN
Background: In the treatment of metastatic pancreatic neuroendocrine tumors (PanNETs), surgical resection is the first choice if curative resection is expected. However, most patients develop recurrence after resection of liver metastasis. Because one of the benefits of resection is to gain a tumor-free period for the patients, it is important to identify which patients achieve longer recurrence-free survival (RFS) by resection. In this study, the clinicopathological factors associated with RFS after resection of metastatic PanNETs in the liver were evaluated to identify the patient group that is suitable for resection.Methods: Consecutively diagnosed patients with PanNET liver metastasis with resection at our hospital from January 2000 to July 2019 were evaluated. A total of 26 metastatic PanNET patients with primary liver resections were evaluated. The median follow-up time was 48.3 months.Results: There were 18 NET recurrences of the total 26 resections, with a median RFS of 17.9 months. Independent risk factors for short RFS were a high Ki67 index (p = .009) and the number of resected tumors (p = .045). When the cut-off value for the Ki67 index was 5.0% and that for the number of resected tumors was 6, Ki67 > 5.0% tumors had shorter RFS (4.9 months vs. 38.2 months p = .006), and patients with tumors > = 7 tumors had shorter RFS (4.7 months vs. 27.5 months p = .001).Conclusions: These findings indicate that good candidates for resection of metastatic tumors of PanNETs could be patients with low Ki67 tumors and a small number of metastatic tumors.
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Antígeno Ki-67/metabolismo , Neoplasias Hepáticas/secundario , Recurrencia Local de Neoplasia/mortalidad , Tumores Neuroendocrinos/mortalidad , Neoplasias Pancreáticas/mortalidad , Adulto , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Tumores Neuroendocrinos/metabolismo , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Factores de Riesgo , Tasa de SupervivenciaRESUMEN
BACKGROUND: We evaluated the clinicopathological factors associated with lymph node metastasis in patients with non-functioning pancreatic neuroendocrine neoplasms (PanNENs), focusing on the risk factors and range of lymph node metastasis for tumors ≤ 2 cm in diameter. METHODS: The subjects of this study were patients with PanNENs consecutively diagnosed at our hospital between January, 2000 and June, 2018. We analyzed 69 patients who underwent R0 resection of a non-functioning sporadic PanNEN with no distant metastasis, as well as 43 patients with tumors ≤ 20 mm in radiological diameter. RESULTS: Nineteen patients (27.5%), including 7 (16.3%) with a small PanNEN, had lymph node metastasis. A large radiological diameter, a high Ki67 index, and cyst formation correlated significantly with positive lymph node metastasis. In patients with tumors ≤ 20 mm in diameter, a high Ki67 index correlated significantly with lymph node metastasis. When we set the cut-off Ki67 index as 3.3%, 2 of 43 patients had lymph node metastasis. Tumors in the uncinate process readily metastasized to the region around the superior mesenteric artery. CONCLUSIONS: These findings suggest that a high Ki67 index indicates a risk of lymph node metastasis for tumors ≤ 20 mm in diameter and that lymphadenectomy should be performed in the region spatially adjacent to the primary tumor.
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Biomarcadores de Tumor/análisis , Antígeno Ki-67/análisis , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Arteria Mesentérica Superior/patología , Persona de Mediana Edad , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/cirugía , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: The primary site of a neuroendocrine neoplasms (NEN) around the head of the pancreas is sometimes difficult to assess before resection, and the characteristics of the primary site around this region have not been elucidated for recurrence after curative resection. In this study, the clinicopathologic characteristics of pancreatic NEN (PanNEN) and duodenal NEN (DuNEN) were evaluated, and the risk factors as well as the recurrence types after resection were investigated. METHODS: Consecutively diagnosed NEN patients at the authors' hospital from January 2000 to July 2016 were evaluated in this study. For 117 PanNEN patients and 31 non-ampullary DuNEN patients, R0 resection was achieved. The median follow-up period was 8.1 years. RESULTS: In this study, 27 PanNEN patients (23.1%) had recurrences, with a median disease-free survival (DFS) of 133 months, whereas 11 DuNEN patients (35.5%) had recurrences, with a median DFS of 156 months. The PanNEN patients tended to have primary recurrence in the liver (85.2%), followed by lymph nodes (11.1%). The independent risk factors for short DFS were lymph node metastasis at resection (p = 0.001) and microvascular invasion (p = 0.048). In contrast, the DuNEN patients were likely to have lymph node metastasis (81.8%). The independent risk factors for short DFS were lymph node metastasis at resection (p = 0.003) and large diameter (p = 0.013). CONCLUSIONS: Most initial recurrences of PanNEN occurred in the liver, whereas those of DuNEN appeared in lymph nodes, suggesting that proper diagnosis of the primary site and appropriate imaging methods for surveillance after resection are necessary.
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Neoplasias Duodenales/cirugía , Recurrencia Local de Neoplasia/diagnóstico , Tumores Neuroendocrinos/cirugía , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Neoplasias Duodenales/patología , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/mortalidad , Tumores Neuroendocrinos/secundario , Neoplasias Pancreáticas/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Adulto JovenRESUMEN
BACKGROUND/OBJECTIVES: Pancreatic fistulas are one of the most frequent morbidities after pancreaticoduodenectomy. Several reports have suggested a relationship between bacterial infections and postoperative pancreatic fistulas, although details of the mechanisms involved in hemorrhage in association with the fistulas have not been elucidated. This study retrospectively examined the relationship between positive drainage culture and hemorrhage associated with pancreatic fistulas after pancreaticoduodenectomy. METHODS: From January 2012 to December 2015, 142 consecutive patients underwent pancreaticoduodenectomy at our institution. We retrospectively reviewed the patients' demographic data, perioperative laboratory data, and drainage culture results. RESULTS: Twenty-four (17%) patients had clinically relevant postoperative pancreatic fistulas, whereas thirty-four (24%) patients experienced positive drainage culture. Multivariable analysis revealed that positive drainage culture was independently associated with clinically relevant postoperative pancreatic fistulas (odds ratio, 18.1; 95% confidence interval, 5.5-72.2; P < 0.001). Additionally, the prevalence of Candida albicans in the lavage of eight patients significantly correlated with hemorrhage associated with pancreatic fistulas (odds ratio, 43.5; 95% confidence interval, 6.2-513.3; P < 0.001). Seventy-five percent (6/8) of these patients suffered potentially lethal hemorrhagic complications and needed intervention. CONCLUSIONS: A positive abdominal drainage culture is associated with the development of pancreatic fistulas. Moreover, the presence of Candida albicans in drainage fluid may be a risk factor for hemorrhagic complications.
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Candida albicans , Candidiasis/complicaciones , Hemorragia/etiología , Fístula Pancreática/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Candidiasis/microbiología , Femenino , Hemorragia/microbiología , Humanos , Masculino , Persona de Mediana Edad , Fístula Pancreática/microbiología , Pancreaticoduodenectomía/efectos adversos , Complicaciones Posoperatorias/microbiología , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Adulto JovenRESUMEN
Notch signaling has been shown to contribute to murine pancreatic development at various stages. Delta-like 1 (Dll1) or Jagged1 (Jag1) are the Notch ligands that solely function to trigger this signaling during the pancreatic bud stage (~e9.5) or after birth, respectively. However, it has not been elucidated whether these Notch ligands are required at the later stage (e10.5-18.5) when the particular pancreas structures form. Here, we detected the dual expression of Dll1 and Jag1 in the epithelium after e10.5, which was restricted to the ductal cell lineage, including centroacinar cells expressing Sox9, CD133 and Hes1 but not the ductal cell markers Hnf1ß and DBA, at e18.5. To evaluate the significance of the Notch ligands during this period, we established double-floxed mice of Dll1 and Jag1 genes with Ptf1a-Cre knock-in allele and examined the effects on development. The abrogation of both ligands but not a single one led to the loss of centroacinar cells, which was due to the decrease in cell proliferation and the increase in cell death, as well as to the reduction of Sox9. These results suggested that Dll1 and Jag1 function redundantly and are necessary to maintain the centroacinar cells as an environmental niche in the developing pancreas.
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Células Acinares/metabolismo , Páncreas/metabolismo , Receptor Notch1/metabolismo , Células Acinares/citología , Animales , Apoptosis , Proteínas de Unión al Calcio/metabolismo , Proliferación Celular , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteína Jagged-1 , Ligandos , Proteínas de la Membrana/metabolismo , Ratones , Ratones Transgénicos , Páncreas/citología , Páncreas/crecimiento & desarrollo , Factor de Transcripción SOX9/metabolismo , Proteínas Serrate-JaggedRESUMEN
PURPOSES: In the surgical treatment of pancreatic cancer, margin-negative status is one of the most important determinants of survival. We conducted this study to explore surgical margin status as well as other factors affecting the survival of borderline-resectable pancreatic cancer (BRPC) patients who received neoadjuvant chemotherapy with gemcitabine and S-1. METHODS: Eighteen BRPC patients were prospectively treated with concurrent gemcitabine and S-1 neoadjuvant chemotherapy (NAC+) and 15 of these patients underwent resection. We evaluated the safety and efficacy of this treatment regimen by comparing the outcomes of these patients with those of 19 BRPC patients who did not receive neoadjuvant chemotherapy (NAC-) during the same period. RESULTS: Fifteen (83 %) of the NAC+ patients underwent pancreatectomy. The remaining three patients (17 %) had regional tumor progression or liver metastasis. Of the 15 NAC+ patients who underwent resection, 3 (20 %) had margin-positive status, whereas 9 of the 19 (43 %) NAC- patients had margin-positive status (p = 0.002). However, disease-free survival and overall survival were similar in the two groups (MST 21.7 vs. 21.1 months). NAC+ patients with tumors smaller than 30 mm had favorable overall survival (MST 43.9 vs. 23.1 months, p = 0.0321). Most recurrences developed at distant sites rather than locally in both groups. CONCLUSIONS: In the neoadjuvant setting, gemcitabine and S-1 improved the negative surgical margin rate in BRPC patients, but it did not improve survival. Thus, neoadjuvant chemotherapy should be given to BRPC patients at an earlier stage.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Neoadyuvante , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Ácido Oxónico/administración & dosificación , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Tasa de Supervivencia , Tegafur/administración & dosificación , Resultado del Tratamiento , GemcitabinaRESUMEN
In the cerebellum, the bHLH transcription factors Ptf1a and Atoh1 are expressed in distinct neuroepithelial regions, the ventricular zone (VZ) and the rhombic lip (RL), and are required for producing GABAergic and glutamatergic neurons, respectively. However, it is unclear whether Ptf1a or Atoh1 is sufficient for specifying GABAergic or glutamatergic neuronal fates. To test this, we generated two novel knock-in mouse lines, Ptf1a(Atoh1) and Atoh1(Ptf1a), that are designed to express Atoh1 and Ptf1a ectopically in the VZ and RL, respectively. In Ptf1a(Atoh1) embryos, ectopically Atoh1-expressing VZ cells produced glutamatergic neurons, including granule cells and deep cerebellar nuclei neurons. Correspondingly, in Atoh1(Ptf1a) animals, ectopically Ptf1a-expressing RL cells produced GABAergic populations, such as Purkinje cells and GABAergic interneurons. Consistent results were also obtained from in utero electroporation of Ptf1a or Atoh1 into embryonic cerebella, suggesting that Ptf1a and Atoh1 are essential and sufficient for GABAergic versus glutamatergic specification in the neuroepithelium. Furthermore, birthdating analyses with BrdU in the knock-in mice or with electroporation studies showed that ectopically produced fate-changed neuronal types were generated at temporal schedules closely simulating those of the wild-type RL and VZ, suggesting that the VZ and RL share common temporal information. Observations of knock-in brains as well as electroporated brains revealed that Ptf1a and Atoh1 mutually negatively regulate their expression, probably contributing to formation of non-overlapping neuroepithelial domains. These findings suggest that Ptf1a and Atoh1 specify spatial identities of cerebellar neuron progenitors in the neuroepithelium, leading to appropriate production of GABAergic and glutamatergic neurons, respectively.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Cerebelo/citología , Ácido Glutámico/metabolismo , Células-Madre Neurales/fisiología , Neuronas/metabolismo , Factores de Transcripción/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Factores de Edad , Animales , Animales Recién Nacidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/genética , Cerebelo/embriología , Embrión de Mamíferos , Regulación del Desarrollo de la Expresión Génica/genética , Antígeno Ki-67/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación/genética , Factores de Transcripción/genéticaRESUMEN
The functional cells or tissues derived from human induced pluripotent stem cells (iPSCs) make it possible to overcome with the insufficiency of cell sources for regenerative medicine, to investigate the precise mechanism of human organogenesis and disease, and to develop the new drugs. Especially for type 1 diabetes, making mature pancreatic beta cells from human iPSCs might have a good opportunity of regenerative medicine. However, so far in vitro, producing the fully maturated pancreatic beta cells is not achieved. Here we review the previous reports and discuss the possibility and validity of our strategy for making mature pancreatic beta cell with three-dimensional culture of pancreatic organoid derived from human iPSCs.
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Células Madre Pluripotentes Inducidas/citología , Páncreas/citología , Adenosina Trifosfato/metabolismo , Animales , Diferenciación Celular , Humanos , Páncreas/metabolismo , Medicina Regenerativa/métodosRESUMEN
Ca(2+)-dependent activator protein for secretion 1 (CAPS1) plays a regulatory role in the dense-core vesicle (DCV) exocytosis pathway, but its functions at the cellular and synaptic levels in the brain are essentially unknown because of neonatal death soon after birth in Caps1 knock-out mice. To clarify the functions of the protein in the brain, we generated two conditional knock-out (cKO) mouse lines: 1) one lacking Caps1 in the forebrain; and 2) the other lacking Caps1 in the cerebellum. Both cKO mouse lines were born normally and grew to adulthood, although they showed subcellular and synaptic abnormalities. Forebrain-specific Caps1 cKO mice showed reduced immunoreactivity for the DCV marker secretogranin II (SgII) and the trans-Golgi network (TGN) marker syntaxin 6, a reduced number of presynaptic DCVs, and dilated trans-Golgi cisternae in the CA3 region. Cerebellum-specific Caps1 cKO mice had decreased immunoreactivity for SgII and brain-derived neurotrophic factor (BDNF) along the climbing fibers. At climbing fiber-Purkinje cell synapses, the number of DCVs was markedly lower and the number of synaptic vesicles was also reduced. Correspondingly, the mean amplitude of EPSCs was decreased, whereas paired-pulse depression was significantly increased. Our results suggest that loss of CAPS1 disrupts the TGN-DCV pathway, which possibly impairs synaptic transmission by reducing the presynaptic release probability.
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Encéfalo/metabolismo , Proteínas de Unión al Calcio/deficiencia , Aparato de Golgi/metabolismo , Proteínas del Tejido Nervioso/deficiencia , Terminales Presinápticos/metabolismo , Vesículas Secretoras/metabolismo , Animales , Encéfalo/ultraestructura , Aparato de Golgi/ultraestructura , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Terminales Presinápticos/ultraestructura , Probabilidad , Transporte de Proteínas/genética , Vesículas Secretoras/ultraestructuraRESUMEN
BACKGROUND AND PURPOSE: To evaluate the treatment outcomes of radiotherapy and prognostic factors for recurrent pancreatic cancer. PATIENTS AND METHODS: The study comprised 30 patients who developed a locoregional recurrence of primarily resected pancreatic cancer and received radiotherapy between 2000 and 2013 with a median dose of 54 Gy (range, 39-60 Gy). Concurrent chemotherapy included gemcitabine for 18 patients and S-1 for seven patients. The treatment outcomes and prognostic factors were retrospectively analyzed. RESULTS: The median follow-up after radiotherapy was 14.6 months. The 1-year overall survival, local control, and progression-free survival rates were 69%, 67%, and 32%, respectively. The median overall survival and progression-free survival rates were 15.9 and 6.9 months, respectively. Tumor marker reduction and ≥ 50% reduction were observed in 18 and two patients, respectively. Of the seven patients who exhibited pain symptoms, four and two patients were partly and completely relieved, respectively. Late grade 3 ileus and gastroduodenal bleeding were observed in one patient each. Among the clinicopathological factors evaluated, only a disease-free interval of greater than 18.9 months exhibited a significant association with improved overall survival (p = 0.017). CONCLUSIONS: Radiotherapy for isolated locally recurrent pancreatic cancer resulted in encouraging local control, overall survival, and palliative effects with mild toxicity, particularly in patients with a prolonged disease-free interval. This treatment strategy should be prospectively evaluated.
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Quimioradioterapia Adyuvante , Recurrencia Local de Neoplasia/radioterapia , Pancreatectomía , Neoplasias Pancreáticas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ácido Oxónico/administración & dosificación , Dimensión del Dolor , Cuidados Paliativos/métodos , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Dosificación Radioterapéutica , Tegafur/administración & dosificación , GemcitabinaRESUMEN
Recent advances have made modeling human small intestines in vitro possible, but it remains a challenge to recapitulate fully their structural and functional characteristics. We suspected interstitial flow within the intestine, powered by circulating blood plasma during embryonic organogenesis, to be a vital factor. We aimed to construct an in vivo-like multilayered small intestinal tissue by incorporating interstitial flow into the system and, in turn, developed the micro-small intestine system by differentiating definitive endoderm and mesoderm cells from human pluripotent stem cells simultaneously on a microfluidic device capable of replicating interstitial flow. This approach enhanced cell maturation and led to the development of a three-dimensional small intestine-like tissue with villi-like epithelium and an aligned mesenchymal layer. Our micro-small intestine system not only overcomes the limitations of conventional intestine models but also offers a unique opportunity to gain insights into the detailed mechanisms underlying intestinal tissue development.
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In the central nervous system, astrocytes enable appropriate synapse function through glutamate clearance from the synaptic cleft; however, it remains unclear how astrocytic glutamate transporters function at peri-synaptic contact. Here, we report that Down syndrome cell adhesion molecule (DSCAM) in Purkinje cells controls synapse formation and function in the developing cerebellum. Dscam-mutant mice show defects in CF synapse translocation as is observed in loss of function mutations in the astrocytic glutamate transporter GLAST expressed in Bergmann glia. These mice show impaired glutamate clearance and the delocalization of GLAST away from the cleft of parallel fibre (PF) synapse. GLAST complexes with the extracellular domain of DSCAM. Riluzole, as an activator of GLAST-mediated uptake, rescues the proximal impairment in CF synapse formation in Purkinje cell-selective Dscam-deficient mice. DSCAM is required for motor learning, but not gross motor coordination. In conclusion, the intercellular association of synaptic and astrocyte proteins is important for synapse formation and function in neural transmission.
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Neuroglía , Neuronas , Animales , Ratones , Sistema de Transporte de Aminoácidos X-AG/metabolismo , Cerebelo/metabolismo , Ácido Glutámico/metabolismo , Neuroglía/metabolismo , Neuronas/metabolismo , Células de Purkinje/metabolismo , Sinapsis/metabolismoRESUMEN
Pancreas development begins with the formation of buds at specific sites in the embryonic foregut endoderm. We used recombination-based lineage tracing in vivo to show that Ptf1a (also known as PTF1-p48) is expressed at these early stages in the progenitors of pancreatic ducts, exocrine and endocrine cells, rather than being an exocrine-specific gene as previously described. Moreover, inactivation of Ptf1a switches the character of pancreatic progenitors such that their progeny proliferate in and adopt the normal fates of duodenal epithelium, including its stem-cell compartment. Consistent with the proposal that Ptf1a supports the specification of precursors of all three pancreatic cell types, transgene-based expression of Pdx1, a gene essential to pancreas formation, from Ptf1a cis-regulatory sequences restores pancreas tissue to Pdx1-null mice that otherwise lack mature exocrine and endocrine cells because of an early arrest in organogenesis. These experiments provide evidence that Ptf1a expression is specifically connected to the acquisition of pancreatic fate by undifferentiated foregut endoderm.
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Duodeno/embriología , Regulación de la Expresión Génica , Proteínas de Homeodominio , Páncreas/embriología , Factores de Transcripción/fisiología , Animales , Animales Modificados Genéticamente , Diferenciación Celular , Linaje de la Célula , Duodeno/citología , Ratones , Páncreas/citología , Transactivadores/metabolismoRESUMEN
BACKGROUND: Resectable pancreatic cancer (RPC) is potentially resectable on admission, and the impact of neoadjuvant therapy on these tumors is controversial. Moreover, the safety and efficacy of neoadjuvant chemoradiotherapy with moderately hypofractionated intensity-modulated radiation therapy (NACIMRT) for RPC have not been studied. Here, we conducted a phase II study to evaluate the safety and efficacy of hypofractionated NACIMRT for RPC. METHODS: A total of 54 RPC patients were enrolled and treated according to the study protocol. We used moderately hypofractionated (45 Gy in 15 fractions) IMRT with gemcitabine to shorten the duration of radiotherapy and reduce gastrointestinal toxicity. The primary endpoint was overall survival (OS), and we subsequently analyzed the microscopically margin-negative resection (R0) rate, disease-free survival (DFS), and histologic effects and safety of NACIMRT. RESULTS: Median OS for the cohort was 40.0 months. Forty-two patients (77.8%) underwent pancreatectomy after NACIMRT. Median DFS was 20.3 months. The R0 resection rate was 95.2% (40/42) per protocol and 85.2% (46/54) for the cohort. There were no intervention-related deaths during the study period. Local treatment response, as assessed by the CAP classification, showed no residual tumor in 4.8% of patients. Overall, 23.9% of patients experienced CTCAE grade 3 or 4 during NACIMRT. Adjuvant therapy was initiated in 88% of patients undergoing resection. Postoperative complications grade ≥3b on the Clavien-Dindo scale occurred in 4.8% of patients. CA19-9 level at enrollment was an independent prognostic factor for OS and DFS. CONCLUSIONS: This is the first prospective study of hypofractionated IMRT as neoadjuvant therapy for RPC. Hypofractionated NACIMRT for RPC could be safely introduced with a high induction rate of adjuvant chemotherapy, with an overall survival of 40.0 months.
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During brain development, neurons and glias are generated from neural stem cells and more limited intermediate neural progenitors (INPs). Numerous studies have revealed the mechanisms of development of neural stem cells. However, the signaling pathways that govern the development of INPs are largely unknown. The cerebellum is suitable for examining this issue because cerebellar cortical inhibitory neurons such as basket and stellate cells are derived from small Pax2(+) interneuronal progenitors. Here, we show that Sox2(-)/Pax2(+) and Sox2(+)/Pax2(-) progenitors, 2 types of interneuronal progenitors of basket and stellate cells, exist in the cerebellar white matter (WM) and that the former arise from the latter during the first postnatal week. Moreover, RBP-J promotes the neurogenesis of stellate and basket cells by converting Sox2(+)/Pax2(-) interneuronal progenitors to more mature Sox2(-)/Pax2(+) interneuronal progenitors. This study shows a novel RBP-J function that promotes INP differentiation.
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Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/metabolismo , Células-Madre Neurales/metabolismo , Neurogénesis , Neuronas/metabolismo , Animales , Apoptosis/genética , Cerebelo/citología , Cerebelo/metabolismo , Femenino , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/genética , Inmunohistoquímica , Hibridación in Situ , Interneuronas/citología , Interneuronas/metabolismo , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Neuronas/citología , Factor de Transcripción PAX2/genética , Factor de Transcripción PAX2/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Transducción de SeñalRESUMEN
To evaluate the role of oncogenic RAS mutations in pancreatic tumorigenesis, we directed endogenous expression of KRAS(G12D) to progenitor cells of the mouse pancreas. We find that physiological levels of Kras(G12D) induce ductal lesions that recapitulate the full spectrum of human pancreatic intraepithelial neoplasias (PanINs), putative precursors to invasive pancreatic cancer. The PanINs are highly proliferative, show evidence of histological progression, and activate signaling pathways normally quiescent in ductal epithelium, suggesting potential therapeutic and chemopreventive targets for the cognate human condition. At low frequency, these lesions also progress spontaneously to invasive and metastatic adenocarcinomas, establishing PanINs as definitive precursors to the invasive disease. Finally, mice with PanINs have an identifiable serum proteomic signature, suggesting a means of detecting the preinvasive state in patients.