Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Cell ; 160(1-2): 324-38, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25557080

RESUMEN

Pancreatic cancer is one of the most lethal malignancies due to its late diagnosis and limited response to treatment. Tractable methods to identify and interrogate pathways involved in pancreatic tumorigenesis are urgently needed. We established organoid models from normal and neoplastic murine and human pancreas tissues. Pancreatic organoids can be rapidly generated from resected tumors and biopsies, survive cryopreservation, and exhibit ductal- and disease-stage-specific characteristics. Orthotopically transplanted neoplastic organoids recapitulate the full spectrum of tumor development by forming early-grade neoplasms that progress to locally invasive and metastatic carcinomas. Due to their ability to be genetically manipulated, organoids are a platform to probe genetic cooperation. Comprehensive transcriptional and proteomic analyses of murine pancreatic organoids revealed genes and pathways altered during disease progression. The confirmation of many of these protein changes in human tissues demonstrates that organoids are a facile model system to discover characteristics of this deadly malignancy.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Modelos Biológicos , Técnicas de Cultivo de Órganos , Organoides/patología , Neoplasias Pancreáticas/patología , Animales , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Páncreas/metabolismo , Páncreas/patología
2.
Nucleic Acids Res ; 48(7): e40, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32083660

RESUMEN

Measuring minimal residual disease in cancer has applications for prognosis, monitoring treatment and detection of recurrence. Simple sequence-based methods to detect nucleotide substitution variants have error rates (about 10-3) that limit sensitive detection. We developed and characterized the performance of MASQ (multiplex accurate sensitive quantitation), a method with an error rate below 10-6. MASQ counts variant templates accurately in the presence of millions of host genomes by using tags to identify each template and demanding consensus over multiple reads. Since the MASQ protocol multiplexes 50 target loci, we can both integrate signal from multiple variants and capture subclonal response to treatment. Compared to existing methods for variant detection, MASQ achieves an excellent combination of sensitivity, specificity and yield. We tested MASQ in a pilot study in acute myeloid leukemia (AML) patients who entered complete remission. We detect leukemic variants in the blood and bone marrow samples of all five patients, after induction therapy, at levels ranging from 10-2 to nearly 10-6. We observe evidence of sub-clonal structure and find higher target variant frequencies in patients who go on to relapse, demonstrating the potential for MASQ to quantify residual disease in AML.


Asunto(s)
Leucemia Mieloide Aguda/genética , Algoritmos , Genómica/métodos , Humanos , Leucemia Mieloide Aguda/terapia , Mutación , Neoplasia Residual , Proyectos Piloto , Recurrencia , Inducción de Remisión , Secuenciación Completa del Genoma
3.
Nat Genet ; 47(5): 539-43, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25822087

RESUMEN

RAS network activation is common in human cancers, and in acute myeloid leukemia (AML) this activation is achieved mainly through gain-of-function mutations in KRAS, NRAS or the receptor tyrosine kinase FLT3. We show that in mice, premalignant myeloid cells harboring a Kras(G12D) allele retained low levels of Ras signaling owing to negative feedback involving Spry4 that prevented transformation. In humans, SPRY4 is located on chromosome 5q, a region affected by large heterozygous deletions that are associated with aggressive disease in which gain-of-function mutations in the RAS pathway are rare. These 5q deletions often co-occur with chromosome 17 alterations involving the deletion of NF1 (another RAS negative regulator) and TP53. Accordingly, combined suppression of Spry4, Nf1 and p53 produces high levels of Ras signaling and drives AML in mice. Thus, SPRY4 is a tumor suppressor at 5q whose disruption contributes to a lethal AML subtype that appears to acquire RAS pathway activation through a loss of negative regulators.


Asunto(s)
Carcinogénesis/genética , Leucemia Mieloide Aguda/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Animales , Genes Supresores de Tumor , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Mutación Missense , Células 3T3 NIH , Proteínas del Tejido Nervioso/genética
4.
Genome Biol ; 12(9): R97, 2011 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-21958622

RESUMEN

BACKGROUND: Human exome resequencing using commercial target capture kits has been and is being used for sequencing large numbers of individuals to search for variants associated with various human diseases. We rigorously evaluated the capabilities of two solution exome capture kits. These analyses help clarify the strengths and limitations of those data as well as systematically identify variables that should be considered in the use of those data. RESULTS: Each exome kit performed well at capturing the targets they were designed to capture, which mainly corresponds to the consensus coding sequences (CCDS) annotations of the human genome. In addition, based on their respective targets, each capture kit coupled with high coverage Illumina sequencing produced highly accurate nucleotide calls. However, other databases, such as the Reference Sequence collection (RefSeq), define the exome more broadly, and so not surprisingly, the exome kits did not capture these additional regions. CONCLUSIONS: Commercial exome capture kits provide a very efficient way to sequence select areas of the genome at very high accuracy. Here we provide the data to help guide critical analyses of sequencing data derived from these products.


Asunto(s)
Exoma , Juego de Reactivos para Diagnóstico/normas , Análisis de Secuencia de ADN/métodos , Algoritmos , Secuencia de Bases , Línea Celular , Biología Computacional , Secuencia de Consenso , ADN/genética , Biblioteca de Genes , Genoma Humano , Proyecto Mapa de Haplotipos , Humanos , Anotación de Secuencia Molecular , Sistemas de Lectura Abierta , Sensibilidad y Especificidad
5.
Genome Biol ; 12(9): R86, 2011 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-21917142

RESUMEN

We report the development and optimization of reagents for in-solution, hybridization-based capture of the mouse exome. By validating this approach in a multiple inbred strains and in novel mutant strains, we show that whole exome sequencing is a robust approach for discovery of putative mutations, irrespective of strain background. We found strong candidate mutations for the majority of mutant exomes sequenced, including new models of orofacial clefting, urogenital dysmorphology, kyphosis and autoimmune hepatitis.


Asunto(s)
Análisis Mutacional de ADN/métodos , Exoma , Genómica/métodos , Mutación , Animales , Mapeo Cromosómico , Cromosomas de los Mamíferos/genética , Colágeno Tipo II/genética , Exones , Frecuencia de los Genes , Genotipo , Mutación INDEL , Indicadores y Reactivos/normas , Quinasas Quinasa Quinasa PAM/genética , Ratones , Ratones Endogámicos , Fenotipo , Proteina Quinasa Quinasa Quinasa 11 Activada por Mitógeno
6.
Proc Natl Acad Sci U S A ; 103(30): 11234-9, 2006 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-16844783

RESUMEN

Genomic amplifications and deletions, the consequence of somatic variation, are a hallmark of human cancer. Such variation has also been observed between "normal" individuals, as well as in individuals with congenital disorders. Thus, copy number measurement is likely to be an important tool for the analysis of genetic variation, genetic disease, and cancer. We developed representational oligonucleotide microarray analysis, a high-resolution comparative genomic hybridization methodology, with this aim in mind, and reported its use in the study of humans. Here we report the development of a representational oligonucleotide microarray analysis microarray for the genomic analysis of the mouse, an important model system for many genetic diseases and cancer. This microarray was designed based on the sequence assembly MM3, and contains approximately 84,000 probes randomly distributed throughout the mouse genome. We demonstrate the use of this array to identify copy number changes in mouse cancers, as well to determine copy number variation between inbred strains of mice. Because restriction endonuclease digestion of genomic DNA is an integral component of our method, differences due to polymorphisms at the restriction enzyme cleavage sites are also observed between strains, and these can be useful to follow the inheritance of loci between crosses of different strains.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Oligonucleótidos/química , Animales , Cruzamientos Genéticos , Genoma , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Hibridación de Ácido Nucleico , Polimorfismo Genético , Especificidad de la Especie
7.
Cell ; 125(7): 1253-67, 2006 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-16814713

RESUMEN

The heterogeneity and instability of human tumors hamper straightforward identification of cancer-causing mutations through genomic approaches alone. Herein we describe a mouse model of liver cancer initiated from progenitor cells harboring defined cancer-predisposing lesions. Genome-wide analyses of tumors in this mouse model and in human hepatocellular carcinomas revealed a recurrent amplification at mouse chromosome 9qA1, the syntenic region of human chromosome 11q22. Gene-expression analyses delineated cIAP1, a known inhibitor of apoptosis, and Yap, a transcription factor, as candidate oncogenes in the amplicon. In the genetic context of their amplification, both cIAP1 and Yap accelerated tumorigenesis and were required to sustain rapid growth of amplicon-containing tumors. Furthermore, cIAP1 and Yap cooperated to promote tumorigenesis. Our results establish a tractable model of liver cancer, identify two oncogenes that cooperate by virtue of their coamplification in the same genomic locus, and suggest an efficient strategy for the annotation of human cancer genes.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Oncogenes , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Proteínas de Ciclo Celular , Genes p53 , Genómica , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , Neoplasias Hepáticas Experimentales/etiología , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/patología , Ratones , Ratones Noqueados , Mutación , Proteínas Nucleares/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfoproteínas/genética , Especificidad de la Especie , Transactivadores/genética , Factores de Transcripción , Proteínas Señalizadoras YAP
8.
Cell ; 123(4): 545-8, 2005 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-16286002

RESUMEN

In response to DNA damage, the tumor suppressor p53 elicits a complex cellular response. In this issue of Cell, Wu et al. (2005) show that the transcription factor SLUG is induced by p53 and protects hematopoietic progenitor cells from apoptosis triggered by DNA damage. SLUG exerts this protective role by repressing Puma, a proapoptotic target of p53. PUMA is also a key coordinator of apoptosis mediated by both nuclear and cytoplasmic functions of p53 (Chi-puk et al., 2005).


Asunto(s)
Apoptosis/fisiología , Factores de Transcripción/fisiología , Proteína p53 Supresora de Tumor/fisiología , Proteínas Supresoras de Tumor/fisiología , Animales , Proteínas Reguladoras de la Apoptosis/fisiología , Daño del ADN , Células Madre Hematopoyéticas/fisiología , Células Madre Hematopoyéticas/efectos de la radiación , Humanos , Ratones , Modelos Biológicos , Proteínas Represoras/fisiología , Factores de Transcripción de la Familia Snail , Proteína X Asociada a bcl-2/fisiología , Proteína bcl-X/fisiología
9.
Dev Biol ; 274(1): 125-38, 2004 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-15355793

RESUMEN

Programmed cell death occurs in every multicellular organism and in diverse cell types yet the genetic controls that define which cells will live and which will die remain poorly understood. During development of the nematode Caenorhabditis elegans, the coordinated activity of four gene products, EGL-1, CED-9, CED-4 and CED-3, results in the death of essentially all cells fated to die. To identify novel upstream components of the cell death pathway, we performed a genetic screen for mutations that abolish the death of the hermaphrodite-specific neurons (HSNs), a homologous pair of cells required for egg-laying in the hermaphrodite. We identified and cloned the genes, eor-1 and eor-2, which are required to specify the fate of cell death in male HSNs. In addition to defects in HSN death, mutation of either gene leads to defects in coordinated movement, neuronal migration, male tail development, and viability; all consistent with abnormal neuronal differentiation. eor-1 encodes a putative transcription factor related to the human oncogene PLZF. eor-2 encodes a novel but conserved protein. We propose that eor-1 and eor-2 function together throughout the nervous system to promote terminal differentiation of neurons and function specifically in male HSNs to promote apoptotic death of the HSNs.


Asunto(s)
Apoptosis/fisiología , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/embriología , Proteínas Nucleares/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/fisiología , Diferenciación Celular/fisiología , Cartilla de ADN , Femenino , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/metabolismo , Datos de Secuencia Molecular , Mutación/genética , Neuronas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/fisiología , Reacción en Cadena de la Polimerasa , Proteínas Represoras/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA