Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Annu Rev Cell Dev Biol ; 35: 567-589, 2019 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-31553635

RESUMEN

Deafness or hearing deficits are debilitating conditions. They are often caused by loss of sensory hair cells or defects in their function. In contrast to mammals, nonmammalian vertebrates robustly regenerate hair cells after injury. Studying the molecular and cellular basis of nonmammalian vertebrate hair cell regeneration provides valuable insights into developing cures for human deafness. In this review, we discuss the current literature on hair cell regeneration in the context of other models for sensory cell regeneration, such as the retina and the olfactory epithelium. This comparison reveals commonalities with, as well as differences between, the different regenerating systems, which begin to define a cellular and molecular blueprint of regeneration. In addition, we propose how new technical advances can address outstanding questions in the field.


Asunto(s)
Células Madre Adultas/metabolismo , Oído Interno/metabolismo , Células Ciliadas Auditivas/fisiología , Mucosa Olfatoria/metabolismo , Regeneración/fisiología , Retina/metabolismo , Animales , Diferenciación Celular/genética , Proliferación Celular/genética , Citocinas/metabolismo , Oído Interno/citología , Células Ciliadas Auditivas/citología , Células Ciliadas Auditivas/metabolismo , Humanos , Inflamación/genética , Inflamación/metabolismo , Macrófagos/metabolismo , Regeneración/genética , Retina/citología , Transducción de Señal/genética , Transducción de Señal/fisiología , Heridas y Lesiones/genética , Heridas y Lesiones/metabolismo
2.
Nucleic Acids Res ; 50(4): 2319-2333, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35141752

RESUMEN

Staphylococcus aureus is a notorious and globally distributed pathogenic bacterium. New strategies to develop novel antibiotics based on intrinsic bacterial toxin-antitoxin (TA) systems have been recently reported. Because TA systems are present only in bacteria and not in humans, these distinctive systems are attractive targets for developing antibiotics with new modes of action. S. aureus PemIK is a type II TA system, comprising the toxin protein PemK and the labile antitoxin protein PemI. Here, we determined the crystal structures of both PemK and the PemIK complex, in which PemK is neutralized by PemI. Our biochemical approaches, including fluorescence quenching and polarization assays, identified Glu20, Arg25, Thr48, Thr49, and Arg84 of PemK as being important for RNase function. Our study indicates that the active site and RNA-binding residues of PemK are covered by PemI, leading to unique conformational changes in PemK accompanied by repositioning of the loop between ß1 and ß2. These changes can interfere with RNA binding by PemK. Overall, PemK adopts particular open and closed forms for precise neutralization by PemI. This structural and functional information on PemIK will contribute to the discovery and development of novel antibiotics in the form of peptides or small molecules inhibiting direct binding between PemI and PemK.


Asunto(s)
Antitoxinas , Staphylococcus aureus , Antibacterianos/metabolismo , Antitoxinas/genética , Antitoxinas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ARN/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
3.
Dev Dyn ; 251(2): 336-349, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34174014

RESUMEN

BACKGROUND: Lymphatic vascular development is regulated by well-characterized signaling and transcriptional pathways. These pathways regulate lymphatic endothelial cell (LEC) migration, motility, polarity, and morphogenesis. Canonical and non-canonical WNT signaling pathways are known to control LEC polarity and development of lymphatic vessels and valves. PKD1, encoding Polycystin-1, is the most commonly mutated gene in polycystic kidney disease but has also been shown to be essential in lymphatic vascular morphogenesis. The mechanism by which Pkd1 acts during lymphangiogenesis remains unclear. RESULTS: Here we find that loss of non-canonical WNT signaling components Wnt5a and Ryk phenocopy lymphatic defects seen in Pkd1 knockout mice. To investigate genetic interaction, we generated Pkd1;Wnt5a double knockout mice. Loss of Wnt5a suppressed phenotypes seen in the lymphatic vasculature of Pkd1-/- mice and Pkd1 deletion suppressed phenotypes observed in Wnt5a-/- mice. Thus, we report mutually suppressive roles for Pkd1 and Wnt5a, with developing lymphatic networks restored to a more wild type state in double mutant mice. This genetic interaction between Pkd1 and the non-canonical WNT signaling pathway ultimately controls LEC polarity and the morphogenesis of developing vessel networks. CONCLUSION: Our work suggests that Pkd1 acts at least in part by regulating non-canonical WNT signaling during the formation of lymphatic vascular networks.


Asunto(s)
Vasos Linfáticos , Enfermedades Renales Poliquísticas , Animales , Vasos Linfáticos/metabolismo , Ratones , Ratones Noqueados , Morfogénesis/genética , Enfermedades Renales Poliquísticas/genética , Enfermedades Renales Poliquísticas/metabolismo , Proteína Quinasa C , Proteínas Tirosina Quinasas Receptoras/metabolismo , Vía de Señalización Wnt/genética , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
4.
Dev Cell ; 57(6): 799-819.e6, 2022 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-35316618

RESUMEN

Loss of sensory hair cells (HCs) in the mammalian inner ear leads to permanent hearing and vestibular defects, whereas loss of HCs in zebrafish results in their regeneration. We used single-cell RNA sequencing (scRNA-seq) to characterize the transcriptional dynamics of HC regeneration in zebrafish at unprecedented spatiotemporal resolution. We uncovered three sequentially activated modules: first, an injury/inflammatory response and downregulation of progenitor cell maintenance genes within minutes after HC loss; second, the transient activation of regeneration-specific genes; and third, a robust re-activation of developmental gene programs, including HC specification, cell-cycle activation, ribosome biogenesis, and a metabolic switch to oxidative phosphorylation. The results are relevant not only for our understanding of HC regeneration and how we might be able to trigger it in mammals but also for regenerative processes in general. The data are searchable and publicly accessible via a web-based interface.


Asunto(s)
Análisis de la Célula Individual , Pez Cebra , Animales , Expresión Génica , Perfilación de la Expresión Génica , Cabello , Mamíferos/genética , Pez Cebra/genética
5.
Pharmaceuticals (Basel) ; 14(7)2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34206901

RESUMEN

Lymphangiogenesis, the formation of new lymphatic vessels from pre-existing vasculature, plays critical roles in disease, including in cancer metastasis and chronic inflammation. Preclinical and recent clinical studies have now demonstrated therapeutic utility for several anti-lymphangiogenic agents, but optimal agents and efficacy in different settings remain to be determined. We tested the anti-lymphangiogenic property of 3,4-Difluorobenzocurcumin (CDF), which has previously been implicated as an anti-cancer agent, using zebrafish embryos and cultured vascular endothelial cells. We used transgenic zebrafish labelling the lymphatic system and found that CDF potently inhibits lymphangiogenesis during embryonic development. We also found that the parent compound, Curcumin, does not inhibit lymphangiogenesis. CDF blocked lymphatic and venous sprouting, and lymphatic migration in the head and trunk of the embryo. Mechanistically, CDF impaired VEGFC-VEGFR3-ERK signalling in vitro and in vivo. In an in vivo pathological model of Vegfc-overexpression, treatment with CDF rescued endothelial cell hyperplasia. CDF did not inhibit the kinase activity of VEGFR3 yet displayed more prolonged activity in vivo than previously reported kinase inhibitors. These findings warrant further assessment of CDF and its mode of action as a candidate for use in metastasis and diseases of aberrant lymphangiogenesis.

6.
Elife ; 82019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30681411

RESUMEN

Loss of sensory hair cells leads to deafness and balance deficiencies. In contrast to mammalian hair cells, zebrafish ear and lateral line hair cells regenerate from poorly characterized support cells. Equally ill-defined is the gene regulatory network underlying the progression of support cells to differentiated hair cells. scRNA-Seq of lateral line organs uncovered five different support cell types, including quiescent and activated stem cells. Ordering of support cells along a developmental trajectory identified self-renewing cells and genes required for hair cell differentiation. scRNA-Seq analyses of fgf3 mutants, in which hair cell regeneration is increased, demonstrates that Fgf and Notch signaling inhibit proliferation of support cells in parallel by inhibiting Wnt signaling. Our scRNA-Seq analyses set the foundation for mechanistic studies of sensory organ regeneration and is crucial for identifying factors to trigger hair cell production in mammals. The data is searchable and publicly accessible via a web-based interface.


Asunto(s)
Proliferación Celular , Factores de Crecimiento de Fibroblastos/metabolismo , Células Ciliadas Auditivas/citología , ARN Citoplasmático Pequeño/genética , Receptores Notch/metabolismo , Transducción de Señal , Células Madre/metabolismo , Animales , Pez Cebra
7.
Dev Cell ; 49(2): 279-292.e5, 2019 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-31014480

RESUMEN

The correct assignment of cell fate within fields of multipotent progenitors is essential for accurate tissue diversification. The first lymphatic vessels arise from pre-existing veins after venous endothelial cells become specified as lymphatic progenitors. Prox1 specifies lymphatic fate and labels these progenitors; however, the mechanisms restricting Prox1 expression and limiting the progenitor pool remain unknown. We identified a zebrafish mutant that displayed premature, expanded, and prolonged lymphatic specification. The gene responsible encodes the regulator of alternative splicing, Nova2. In zebrafish and human endothelial cells, Nova2 selectively regulates pre-mRNA splicing for components of signaling pathways and phosphoproteins. Nova2-deficient endothelial cells display increased Mapk/Erk signaling, and Prox1 expression is dynamically controlled by Erk signaling. We identify a mechanism whereby Nova2-regulated splicing constrains Erk signaling, thus limiting lymphatic progenitor cell specification. This identifies the capacity of a factor that tunes mRNA splicing to control assignment of cell fate during vascular differentiation.


Asunto(s)
Vasos Linfáticos/metabolismo , Sistema de Señalización de MAP Quinasas , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Empalme Alternativo , Animales , Diferenciación Celular , Linaje de la Célula , Células Endoteliales/citología , Células Endoteliales/metabolismo , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Linfangiogénesis , Vasos Linfáticos/citología , Masculino , Antígeno Ventral Neuro-Oncológico , Proteínas Supresoras de Tumor/metabolismo , Venas/citología , Venas/metabolismo , Pez Cebra
8.
Methods Mol Biol ; 1846: 55-70, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30242752

RESUMEN

The accessibility and optical transparency of the zebrafish embryo offers a unique platform for live-imaging of developmental lymphangiogenesis. Transgenic lines labelling lymphatic progenitors and vessels enable researchers to visualize cellular processes and ask how they contribute to lymphatic development in genetic models. Furthermore, validated immunofluorescence staining for key signaling and cell fate markers (phosphorylated Erk and Prox1) allow single cell resolution studies of lymphatic differentiation. Here, we describe in detail how zebrafish embryos and larvae can be mounted for high resolution, staged imaging of lymphatic networks, how lymphangiogenesis can be reliably quantified and how immunofluorescence can reveal lymphatic signaling and differentiation. These methods offer researchers the opportunity to experimentally dissect developmental lymphangiogenesis with outstanding resolution.


Asunto(s)
Angiografía , Linfangiogénesis , Vasos Linfáticos/embriología , Imagen Molecular , Pez Cebra/embriología , Angiografía/métodos , Animales , Animales Modificados Genéticamente , Células Endoteliales/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Técnica del Anticuerpo Fluorescente , Genes Reporteros , Proteínas de Homeodominio/metabolismo , Imagen Molecular/métodos , Fosforilación , Proteínas Supresoras de Tumor/metabolismo
9.
BMC Dev Biol ; 7: 139, 2007 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-18093315

RESUMEN

BACKGROUND: Wnt signaling is a key regulator of development and tumorigenesis. Protein phosphatase 2A (PP2A), which consists of a catalytic C, a structural A, and a regulatory B subunit, plays diverse roles in Wnt signaling through its B56 subunits. B56 is a multigene family encoding for proteins with a conserved core domain and divergent amino- and carboxy-termini. Ectopic B56alpha and B56gamma reduce beta-catenin abundance and B56alpha reduces Wnt-dependent transcription, suggesting that B56alpha and B56gamma inhibit Wnt signaling. In contrast, B56epsilon is required for Wnt signaling. Knowledge of where and when B56 subunits are expressed during Xenopus development will aid in our understanding of their roles in Wnt signaling. RESULTS: We have undertaken expression analyses of B56alpha and B56gamma in Xenopus laevis. We cloned Xenopus B56alpha; it is 88% identical to human B56alpha. Xenopus B56gamma is 94% identical with human B56gamma, however, a novel evolutionarily conserved mixed-isoform transcript was identified that contains a B56delta-like amino-terminal domain and a B56gamma core domain. The B56delta-like variable domain exon is located upstream of the B56gamma variable domain exon at the human B56gamma locus, suggesting that the mixed-isoform transcript is due to alternative splicing. B56gamma transcripts with different 3' ends were identified that lack or possess a 35 base pair sequence, resulting in either a transcript similar to human B56gamma1, or an uncharacterized evolutionarily conserved sequence. Real time RT-PCR analyses revealed that B56alpha is expressed at moderate levels before the midblastula transition (MBT), at reduced levels during gastrulation and neurulation, and at high levels during organogenesis, while B56gamma is expressed at low levels until organogenesis. B56alpha is enriched in the ventral hemisphere pre-MBT, while B56gamma is ventrally enriched post-MBT. Aalpha, Abeta, Calpha and Cbeta are expressed in early Xenopus development, suggesting the presence of a functional heterotrimer. CONCLUSION: Our data suggest that B56 functional diversity is achieved in part through the synthesis of a novel mixed-isoform B56delta/gamma transcript. Our data also suggest that B56alpha functions pre-MBT, inhibiting Wnt signaling on the ventral side of the embryo, and again during organogenesis, while B56gamma functions primarily post-MBT.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Proteína Fosfatasa 2/genética , Proteínas Wnt/genética , Proteínas de Xenopus/genética , Xenopus laevis/embriología , Animales , Dominio Catalítico , Polaridad Celular , Embrión no Mamífero/embriología , Regulación Enzimológica de la Expresión Génica , Biblioteca de Genes , Isoenzimas/genética , Morfogénesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Transducción de Señal , Xenopus laevis/genética
10.
Nat Commun ; 8(1): 1402, 2017 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-29123087

RESUMEN

Forces play diverse roles in vascular development, homeostasis and disease. VE-cadherin at endothelial cell-cell junctions links the contractile acto-myosin cytoskeletons of adjacent cells, serving as a tension-transducer. To explore tensile changes across VE-cadherin in live zebrafish, we tailored an optical biosensor approach, originally established in vitro. We validate localization and function of a VE-cadherin tension sensor (TS) in vivo. Changes in tension across VE-cadherin observed using ratio-metric or lifetime FRET measurements reflect acto-myosin contractility within endothelial cells. Furthermore, we apply the TS to reveal biologically relevant changes in VE-cadherin tension that occur as the dorsal aorta matures and upon genetic and chemical perturbations during embryonic development.


Asunto(s)
Antígenos CD/fisiología , Cadherinas/fisiología , Proteínas de Pez Cebra/fisiología , Pez Cebra/fisiología , Actomiosina/fisiología , Animales , Antígenos CD/genética , Aorta/embriología , Fenómenos Biomecánicos , Cadherinas/genética , Transferencia Resonante de Energía de Fluorescencia , Uniones Intercelulares/fisiología , Mecanotransducción Celular/fisiología , Imagen Molecular , Mutación , Neovascularización Fisiológica/genética , Resistencia a la Tracción/fisiología , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/genética
11.
Nat Neurosci ; 20(6): 774-783, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28459441

RESUMEN

Mural cells of the vertebrate brain maintain vascular integrity and function, play roles in stroke and are involved in maintenance of neural stem cells. However, the origins, diversity and roles of mural cells remain to be fully understood. Using transgenic zebrafish, we identified a population of isolated mural lymphatic endothelial cells surrounding meningeal blood vessels. These meningeal mural lymphatic endothelial cells (muLECs) express lymphatic endothelial cell markers and form by sprouting from blood vessels. In larvae, muLECs develop from a lymphatic endothelial loop in the midbrain into a dispersed, nonlumenized mural lineage. muLEC development requires normal signaling through the Vegfc-Vegfd-Ccbe1-Vegfr3 pathway. Mature muLECs produce vascular growth factors and accumulate low-density lipoproteins from the bloodstream. We find that muLECs are essential for normal meningeal vascularization. Together, these data identify an unexpected lymphatic lineage and developmental mechanism necessary for establishing normal meningeal blood vasculature.


Asunto(s)
Células Endoteliales/fisiología , Meninges/irrigación sanguínea , Neovascularización Fisiológica/fisiología , Factores de Crecimiento Endotelial Vascular/fisiología , Proteínas de Pez Cebra/fisiología , Pez Cebra , Animales , Animales Modificados Genéticamente , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Encéfalo/fisiología , Células Endoteliales/metabolismo , Células Endoteliales/ultraestructura , Femenino , Lipoproteínas LDL/metabolismo , Masculino , Meninges/crecimiento & desarrollo , Meninges/metabolismo , Meninges/fisiología , Transducción de Señal/fisiología , Factores de Crecimiento Endotelial Vascular/biosíntesis , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
12.
Nanoscale Res Lett ; 9(1): 104, 2014 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-24589243

RESUMEN

Matrix metalloproteinase 2 (MMP2) plays critical roles in various diseases, such as atherosclerosis and cancer, and has been suggested to contribute to the instability of atherosclerotic plaque. To visualize MMP2 in pathologic tissues, we developed an aptamer targeting MMP2 protein by performing eight rounds of modified DNA systematic evolution of ligands by exponential enrichment (SELEX). The aptamer showed high affinity for MMP2 (Kd = 5.59 nM), precipitated MMP2, and detected MMP2 protein in pathological tissues such as atherosclerotic plaque and gastric cancer tissues. Furthermore, a MMP2 aptamer-conjugated fluorescent nanoprobe successfully visualized atherosclerotic plaques in apolipoprotein E (ApoE) knockout mice. These results suggest that the devised MMP2 aptamer could be useful for the development of various diagnostic tools.

13.
Blood Res ; 49(3): 162-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25325035

RESUMEN

BACKGROUND: Although adding rituximab to the chemotherapy regimen of cyclophosphamide, vincristine, doxorubicin, and prednisone (R-CHOP) has improved clinical outcomes of patients with diffuse large B-cell lymphoma (DLBCL), several recent studies have shown that the effect of rituximab is dominantly in the non-germinal center (non-GC) subtype compared to the germinal center (GC) subtype. Natural killer (NK) cell count, a surrogate marker of immune status, is associated with clinical outcomes in DLBCL patients in the rituximab era. We investigated whether the impact of NK cells on clinical outcomes differed according to the immunophenotype of DLBCL. METHODS: This study analyzed 72 DLBCL patients treated with R-CHOP between January 2010 and January 2014. RESULTS: Low NK cell counts (<100/µL) were associated with poor progression-free survival (PFS) and overall survival (OS) compared to high NK cell counts. In multivariate analysis, low NK cell count was an independent prognostic factor for PFS and OS. However, survival did not significantly differ between the GC and non-GC subtypes. We examined the clinical influence of NK cells according to the immunophenotype and found that low NK cell counts were significantly associated with poor PFS and OS in non-GC cases, but not in GC cases. CONCLUSION: Low NK cell counts at diagnosis are associated with poor clinical outcomes in DLBCL patients treated with R-CHOP therapy. However, the impact is significant only in non-GC subtype DLBCL, not in the GC subtype.

14.
J Gastroenterol ; 48(11): 1271-82, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23354623

RESUMEN

BACKGROUND: Wilms' tumor 1-associating protein (WTAP) is a nuclear protein that has been associated with the regulation of proliferation and apoptosis. Although its dynamic expression and physiological functions in vascular cells have been reported, its expression and roles in cholangiocarcinoma cells are poorly characterized. METHODS: To examine the expression of WTAP in patient tissues, we performed immunohistochemistry. To examine motility of cholangiocarcinoma cells, we employed Boyden chamber, wound healing and Matrigel invasion assays, and a liver xenograft model. RESULTS: Immunohistochemistry in patient tissues showed WTAP overexpression in cholangiocarcinoma tissues and correlation of WTAP expression with metastasis of cholangiocarcinoma cells. Overexpression or knockdown of WTAP significantly increased or decreased the motility of cholangiocarcinoma cells. Moreover, WTAP overexpression or knockdown significantly increased or decreased tumorigenicity of cholangiocarcinoma cells in an orthotopic xenograft model. Furthermore, microarray study showed that WTAP induce the expressions of MMP7, MMP28, cathepsin H and Muc1. CONCLUSION: WTAP is overexpressed in cholangiocarcinoma and regulates motility of cholangiocarcinoma cells.


Asunto(s)
Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos , Colangiocarcinoma/patología , Proteínas de Neoplasias/fisiología , Proteínas Nucleares/fisiología , Animales , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/metabolismo , Proteínas de Ciclo Celular , Movimiento Celular/fisiología , Proliferación Celular , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/secundario , Colágeno , Cámaras de Difusión de Cultivos , Combinación de Medicamentos , Regulación Neoplásica de la Expresión Génica/fisiología , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Laminina , Ratones , Ratones Desnudos , Invasividad Neoplásica , Trasplante de Neoplasias , Proteoglicanos , Factores de Empalme de ARN , ARN Mensajero/genética , ARN Neoplásico/genética
15.
PLoS Negl Trop Dis ; 7(2): e2073, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23437413

RESUMEN

Dengue virus is a mosquito-borne flavivirus that has a large impact in global health. It is considered as one of the medically important arboviruses, and developing a preventive or therapeutic solution remains a top priority in the medical and scientific community. Drug discovery programs for potential dengue antivirals have increased dramatically over the last decade, largely in part to the introduction of high-throughput assays. In this study, we have developed an image-based dengue high-throughput/high-content assay (HT/HCA) using an innovative computer vision approach to screen a kinase-focused library for anti-dengue compounds. Using this dengue HT/HCA, we identified a group of compounds with a 4-(1-aminoethyl)-N-methylthiazol-2-amine as a common core structure that inhibits dengue viral infection in a human liver-derived cell line (Huh-7.5 cells). Compounds CND1201, CND1203 and CND1243 exhibited strong antiviral activities against all four dengue serotypes. Plaque reduction and time-of-addition assays suggests that these compounds interfere with the late stage of viral infection cycle. These findings demonstrate that our image-based dengue HT/HCA is a reliable tool that can be used to screen various chemical libraries for potential dengue antiviral candidates.


Asunto(s)
Antivirales/aislamiento & purificación , Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , Descubrimiento de Drogas/métodos , Ensayos Analíticos de Alto Rendimiento , Antivirales/química , Línea Celular , Hepatocitos/virología , Humanos , Pruebas de Sensibilidad Microbiana
16.
PLoS One ; 7(6): e39482, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22745766

RESUMEN

BACKGROUND: Lamina-associated polypeptides 2 (LAP2) is a nuclear protein that connects the nuclear lamina with chromatin. Although its critical roles in genetic disorders and hematopoietic malignancies have been described, its expression and roles in digestive tract cancers have been poorly characterized. METHODS: To examine the expression of LAP2 in patient tissues, we performed immunohistochemistry and real-time PCR. To examine motility of cancer cells, we employed Boyden chamber, wound healing and Matrigel invasion assays. To reveal its roles in metastasis in vivo, we used a liver metastasis xenograft model. To investigate the underlying mechanism, a cDNA microarray was conducted. RESULTS: Immunohistochemistry in patient tissues showed widespread expression of LAP2 in diverse digestive tract cancers including stomach, pancreas, liver, and bile duct cancers. Real-time PCR confirmed that LAP2ß is over-expressed in gastric cancer tissues. Knockdown of LAP2ß did not affect proliferation of most digestive tract cancer cells except pancreatic cancer cells. However, knockdown of LAP2ß decreased motility of all tested cancer cells. Moreover, overexpression of LAP2ß increased motility of gastric and pancreatic cancer cells. In the liver metastasis xenograft model, LAP2ß increased metastatic efficacy of gastric cancer cells and mortality in tested mice. cDNA microarrays showed the possibility that myristoylated alanine-rich C kinase substrate (MARCKS) and interleukin6 (IL6) may mediate LAP2ß-regulated motility of cancer cells. CONCLUSIONS: From the above results, we conclude that LAP2 is widely overexpressed in diverse digestive tract cancers and LAP2ß regulates motility of cancer cells and suggest that LAP2ß may have utility for diagnostics and therapeutics in digestive tract cancers.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Neoplasias Gastrointestinales/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Western Blotting , Línea Celular Tumoral , Movimiento Celular/genética , Movimiento Celular/fisiología , Proliferación Celular , Proteínas de Unión al ADN/genética , Neoplasias Gastrointestinales/genética , Humanos , Inmunohistoquímica , Proteínas de la Membrana/genética , Ratones , Ratones Desnudos , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Anat Cell Biol ; 44(3): 204-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22025972

RESUMEN

A low serum level of vitamin D has been associated with an increased incidence of gastrointestinal tract cancers. However, the effects of vitamin D3 have not been investigated in gastric cancer and cholangiocarcinoma. In the present study, we found that vitamin D3 treatment significantly suppressed the viability of gastric cancer and cholangiocarcinoma cells. Moreover, vitamin D3 had a synergistic effect with other anti-cancer drugs, such as paclitaxel, adriamycin, and vinblastine, for suppressing cell viability. To determine the underlying mechanism involved in the regulation of viability by vitamin D3, we examined the effects of vitamin D3 on expression of hedgehog signaling target genes, which has been associated with gastric cancer and cholangiocarcinoma. Vitamin D3 treatment decreased the level of mRNA expression of patched1, Gli1, cyclin D1, and Bcl2, suggesting the possibility that vitamin D3 may act through regulation of hedgehog signaling. From the above results, we conclude that vitamin D3 regulates cell viability in gastric cancer and cholangiocarcinoma.

18.
Anat Cell Biol ; 43(2): 110-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21189991

RESUMEN

Intrahepatic cholangiocarcinoma is the second most common subtype of primary hepatobilliary cancer. Despite advances in surgical and medical therapy, its survival rate remains poor. Compared to hepatocellular carcinoma (HCC), the most common liver malignancy, the underlying mechanisms of cholangiocarcinoma carcinogenesis are poorly characterized. P-cadherin (CDH3) is a cadherin super family member. Although CDH3 is frequently over-expressed in cholangiocarcinoma tissues, its roles have never been characterized. To determine the roles of CDH3 in cholangiocarcinoma, we investigated CDH3 function in HuCCT1 cells using specific siRNA. Transfection with CDH3 siRNA did not affect proliferation of HuCCT1 cells. However, cell migration and invasion were significantly reduced when CDH3 was down-regulated. In addition, expressions of several biomarkers for epithelial-mesenchymal transition (EMT) were not changed by CDH3 down-regulation. These results suggest that CDH3 regulates cell migration independent of EMT in cholangiocarcinoma cells.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA