RESUMEN
Traditionally, the efficacy of cancer treatment in patients with advance or metastatic disease in clinical studies has been studied using overall survival and more recently tumor-based end points such as progression-free survival, measurements of response to treatment. However, these seem not to be the relevant clinical end points in current situation if such end points were no validated as surrogate of overall survival to demonstrate the clinical efficacy. Appropriate, meaningful, primary patient-oriented and patient-reported end points that adequately measure the effects of new therapeutic interventions are then crucial for the advancement of clinical research in metastatic colorectal cancer to complement the results of tumor-based end points. Health-related quality of life (HRQoL) is effectively an evaluation of quality of life and its relationship with health over time. HRQoL includes the patient report at least of the way a disease or its treatment affects its physical, emotional and social well-being. Over the past few years, several phase III trials in a variety of solid cancers have assessed the incremental value of HRQoL in addition to the traditional end points of tumor response and survival results. HRQoL could provide not only complementary clinical data to the primary outcomes, but also more precise predictive and prognostic value. This end point is useful for both clinicians and patients in order to achieve the dogma of precision medicine. The present article examines the use of HRQoL in phase III metastatic colorectal cancer clinical trials, outlines the importance of HRQoL assessment methods, analysis, and results presentation. Moreover, it discusses the relevance of including HRQoL as a primary/co-primary end point to support the progression-free survival results and to assess efficacy of treatment in the advanced disease setting.
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Ensayos Clínicos como Asunto , Neoplasias Colorrectales/terapia , Calidad de Vida , Neoplasias Colorrectales/fisiopatología , Supervivencia sin Enfermedad , HumanosRESUMEN
Chromosomal passengers are proteins that move from centromeres to the spindle midzone during mitosis. Recent experiments show that the passengers inner centromere protein (INCENP) and aurora-B kinase are in a macromolecular complex that might also contain a third passenger, survivin. The chromosomal passenger complex functions throughout mitosis in chromosome condensation and segregation, and at the end of mitosis, in the completion of cytokinesis.
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Proteínas Cromosómicas no Histona/metabolismo , Proteínas Asociadas a Microtúbulos , Microtúbulos/metabolismo , Mitosis/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas/metabolismo , Aurora Quinasa B , Aurora Quinasas , Muerte Celular/fisiología , Proteínas Inhibidoras de la Apoptosis , Proteínas de Neoplasias , SurvivinRESUMEN
We have performed a biochemical and double-stranded RNA-mediated interference (RNAi) analysis of the role of two chromosomal passenger proteins, inner centromere protein (INCENP) and aurora B kinase, in cultured cells of Drosophila melanogaster. INCENP and aurora B function is tightly interlinked. The two proteins bind to each other in vitro, and DmINCENP is required for DmAurora B to localize properly in mitosis and function as a histone H3 kinase. DmAurora B is required for DmINCENP accumulation at centromeres and transfer to the spindle at anaphase. RNAi for either protein dramatically inhibited the ability of cells to achieve a normal metaphase chromosome alignment. Cells were not blocked in mitosis, however, and entered an aberrant anaphase characterized by defects in sister kinetochore disjunction and the presence of large amounts of amorphous lagging chromatin. Anaphase A chromosome movement appeared to be normal, however cytokinesis often failed. DmINCENP and DmAurora B are not required for the correct localization of the kinesin-like protein Pavarotti (ZEN-4/CHO1/MKLP1) to the midbody at telophase. These experiments reveal that INCENP is required for aurora B kinase function and confirm that the chromosomal passengers have essential roles in mitosis.
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Proteínas Cromosómicas no Histona/metabolismo , Segregación Cromosómica/fisiología , Proteínas de Drosophila , Histonas/metabolismo , Cinetocoros/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Anafase/fisiología , Animales , Aurora Quinasa B , Aurora Quinasas , División Celular/fisiología , Células Cultivadas , Proteínas Cromosómicas no Histona/genética , Cromosomas/metabolismo , Drosophila , Metafase/fisiología , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/genética , Microtúbulos/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Telofase/fisiologíaRESUMEN
Eukaryotic chromosomes are capped with repetitive telomere sequences that protect the ends from damage and rearrangements. Telomere repeats are synthesized by telomerase, a ribonucleic acid (RNA)-protein complex. Here, the cloning of the RNA component of human telomerase, termed hTR, is described. The template region of hTR encompasses 11 nucleotides (5'-CUAACCCUAAC) complementary to the human telomere sequence (TTAGGG)n. Germline tissues and tumor cell lines expressed more hTR than normal somatic cells and tissues, which have no detectable telomerase activity. Human cell lines that expressed hTR mutated in the template region generated the predicted mutant telomerase activity. HeLa cells transfected with an antisense hTR lost telomeric DNA and began to die after 23 to 26 doublings. Thus, human telomerase is a critical enzyme for the long-term proliferation of immortal tumor cells.
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División Celular , ADN Nucleotidilexotransferasa/metabolismo , ARN/metabolismo , Animales , Secuencia de Bases , Muerte Celular , Línea Celular , Clonación Molecular , ADN Nucleotidilexotransferasa/antagonistas & inhibidores , ADN Nucleotidilexotransferasa/química , ADN Nucleotidilexotransferasa/genética , Células HeLa , Humanos , Datos de Secuencia Molecular , Oligonucleótidos Antisentido/farmacología , Reacción en Cadena de la Polimerasa , ARN/química , ARN/genética , Moldes Genéticos , Transfección , Células Tumorales CultivadasRESUMEN
Cytoskeletal rearrangements during mitosis must be co-ordinated with chromosome movements. The 'chromosomal passenger' proteins [1], which include the inner centromere protein (INCENP [2]), the Aurora-related serine-threonine protein kinase AIRK2 [3,4] and the unidentified human autoantigen TD-60 [5], have been suggested to integrate mitotic events. These proteins are chromosomal until metaphase but subsequently transfer to the midzone microtubule array and the equatorial cortex during anaphase. Disruption of INCENP function affects both chromosome segregation and completion of cytokinesis [6,7], whereas interference with AIRK2 function primarily affects cytokinesis [3,8]. Here, we report that INCENP is stockpiled in Xenopus eggs in a complex with Xenopus AIRK2 (XAIRK2), and that INCENP and AIRK2 kinase bind one another in vitro. This association was found to be evolutionarily conserved. Sli15p, the binding partner of yeast Aurora kinase Ipl1p, can be recognized as an INCENP family member because of the presence of a conserved carboxy-terminal sequence region, which we term the IN box. This interaction between INCENP and Aurora kinase was found to be biologically relevant. INCENP and AIRK2 colocalized exactly in human cells, and INCENP was required to target AIRK2 correctly to centromeres and the central spindle.
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Centrómero/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Cromosomas Humanos , Proteínas del Citoesqueleto/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Secuencia de Aminoácidos , Aurora Quinasas , Proteínas Cromosómicas no Histona/química , Proteínas del Citoesqueleto/química , Células HeLa , Humanos , Datos de Secuencia Molecular , Unión Proteica , Homología de Secuencia de AminoácidoRESUMEN
The telomerase reverse transcriptase component (TERT) is not expressed in most primary somatic human cells and tissues, but is upregulated in the majority of immortalized cell lines and tumors. Here, we identify the c-Myc transcription factor as a direct mediator of telomerase activation in primary human fibroblasts through its ability to specifically induce TERT gene expression. Through the use of a hormone inducible form of c-Myc (c-Myc-ER), we demonstrate that Myc-induced activation of the hTERT promoter requires an evolutionarily conserved E-box and that c-Myc-ER-induced accumulation of hTERT mRNA takes place in the absence of de novo protein synthesis. These findings demonstrate that the TERT gene is a direct transcriptional target of c-Myc. Since telomerase activation frequently correlates with immortalization and telomerase functions to stabilize telomers in cycling cells, we tested whether Myc-induced activation of TERT gene expression represents an important mechanism through which c-Myc acts to immortalize cells. Employing the rat embryo fibroblast cooperation assay, we show that TERT is unable to substitute for c-Myc in the transformation of primary rodent fibroblasts, suggesting that the transforming activities of Myc extend beyond its ability to activate TERT gene expression and hence telomerase activity.
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Proteínas Bacterianas/metabolismo , Transformación Celular Neoplásica , Isomerasa de Peptidilprolil , Biosíntesis de Proteínas , Proteínas Proto-Oncogénicas c-myc/metabolismo , ADN Polimerasa Dirigida por ARN/biosíntesis , ARN , Telomerasa/biosíntesis , Animales , Secuencia de Bases , Secuencia Conservada , Proteínas de Unión al ADN , Regulación de la Expresión Génica , Humanos , Ratones , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , Proteínas/genética , ADN Polimerasa Dirigida por ARN/genética , Ratas , Homología de Secuencia de Ácido Nucleico , Telomerasa/genética , Transcripción GenéticaRESUMEN
A pregnancy complicated with idiopathic thrombocytopenic purpura is described. Treatment consisted of primary ceasarean section, tubal ligation, and splenectomy with good results for mother and infant. Subsequent successful pregnancies may be anticipated if the thrombocytopenia-complicated pregnancy is managed as described.
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Complicaciones Hematológicas del Embarazo , Embarazo en Diabéticas , Púrpura Trombocitopénica/complicaciones , Adulto , Plaquetas , Cesárea , Femenino , Sangre Fetal , Gastritis/complicaciones , Hemorroides/complicaciones , Humanos , Recién Nacido , Masculino , Embarazo , Púrpura Trombocitopénica/sangre , EsplenectomíaRESUMEN
Aircrew mission effectiveness may uniquely be influenced by subtle psychological factors not ordinarily brought to the attention of psychiatrists. Pilots tend to be bright, articulate, and anxious to resume their aviation duties when grounded. However, these patients are usually well defended, and rarely psychologically attuned or introspective. Greater insight into what constitutes the normal, healthy motivation to fly will help those who make judgments regarding the return of grounded aviators to flying duty. A review of associated birth order, personality theory, industrial and business psychology, aerospace, and psychoanalytic literature is presented. Highlighted are the difficulties inherent in examining the motivation of a healthy, well-defended population. Our conclusion: an examiner's countertransferential feelings are the best available tool for measurement of healthy motivation.
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Medicina Aeroespacial , Personal Militar/psicología , Motivación , Administración de Personal/normas , Selección de Personal/normas , Actitud , Humanos , Psicología Militar , Estados UnidosRESUMEN
Time-dependent light input is an important feature of computational models of the circadian clock. However, publicly available models encoded in standard representations such as the Systems Biology Markup Language (SBML) either do not encode this input or use different mechanisms to do so, which hinders reproducibility of published results as well as model reuse. The authors describe here a numerically continuous function suitable for use in SBML for models of circadian rhythms forced by periodic light-dark cycles. The Input Signal Step Function (ISSF) is broadly applicable to encoding experimental manipulations, such as drug treatments, temperature changes, or inducible transgene expression, which may be transient, periodic, or mixed. It is highly configurable and is able to reproduce a wide range of waveforms. The authors have implemented this function in SBML and demonstrated its ability to modify the behavior of publicly available models to accurately reproduce published results. The implementation of ISSF allows standard simulation software to reproduce specialized circadian protocols, such as the phase-response curve. To facilitate the reuse of this function in public models, the authors have developed software to configure its behavior without any specialist knowledge of SBML. A community-standard approach to represent the inputs that entrain circadian clock models could particularly facilitate research in chronobiology.
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Relojes Circadianos/fisiología , Ritmo Circadiano/fisiología , Biología Computacional/métodos , Modelos Biológicos , Programas Informáticos , Algoritmos , Animales , Lenguajes de Programación , Reproducibilidad de los ResultadosRESUMEN
UNLABELLED: SUSPECTS is a web-based server which combines annotation and sequence-based approaches to prioritize disease candidate genes in large regions of interest. It uses multiple lines of evidence to rank genes quickly and effectively while limiting the effect of annotation bias to significantly improve performance. AVAILABILITY: SUSPECTS is freely available at http://www.genetics.med.ed.ac.uk/suspects/ SUPPLEMENTARY INFORMATION: A quick-start guide in Macromedia Flash format is available at http://www.genetics.med.ed.ac.uk/suspects/help.shtml and Excel spreadsheets detailing the comparative performance of the software are included as Supplementary material.
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Mapeo Cromosómico/métodos , Marcadores Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Análisis de Secuencia de ADN/métodos , Programas Informáticos , Interfaz Usuario-Computador , Humanos , Internet , Sistemas en LíneaRESUMEN
This paper describes a simple method of determining the off-axis illumination distribution for the camera lens alone as well as for the different lens-spectral filter combinations. The results show departures from the cosine fourth distribution in both cases.
RESUMEN
Mutations in the Drosophila gene pavarotti result in the formation of abnormally large cells in the embryonic nervous system. In mitotic cycle 16, cells of pav mutant embryos undergo normal anaphase but then develop an abnormal telophase spindle and fail to undertake cytokinesis. We show that the septin Peanut, actin, and the actin-associated protein Anillin, do not become correctly localized in pav mutants. pav encodes a kinesin-like protein, PAV-KLP, related to the mammalian MKLP-1. In cellularized embryos, the protein is localized to centrosomes early in mitosis, and to the midbody region of the spindle in late anaphase and telophase. We show that Polo kinase associates with PAV-KLP with which it shows an overlapping pattern of subcellular localization during the mitotic cycle and this distribution is disrupted in pav mutants. We suggest that PAV-KLP is required both to establish the structure of the telophase spindle to provide a framework for the assembly of the contractile ring, and to mobilize mitotic regulator proteins.
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División Celular/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insecto , Proteínas de Insectos/fisiología , Proteínas de Microfilamentos , Proteínas Asociadas a Microtúbulos/fisiología , Sistema Nervioso/embriología , Huso Acromático/ultraestructura , Telofase/genética , Actinas/metabolismo , Secuencia de Aminoácidos , Animales , Tamaño de la Célula , Centrosoma/ultraestructura , Clonación Molecular , Proteínas Contráctiles/metabolismo , Drosophila melanogaster/citología , Drosophila melanogaster/embriología , Embrión no Mamífero/ultraestructura , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Mamíferos/metabolismo , Proteínas Asociadas a Microtúbulos/química , Proteínas Asociadas a Microtúbulos/genética , Datos de Secuencia Molecular , Sistema Nervioso/citología , Proteínas Serina-Treonina Quinasas/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad de la Especie , Fracciones Subcelulares/químicaRESUMEN
DISC1 is disrupted by a chromosomal translocation cosegregating with schizophrenia and recurrent major depression in a large Scottish family and has also been reported as a potential susceptibility locus in independent populations. We reveal a widespread and complex pattern of DISC1 expression, with at least five forms of Disrupted in Schizophrenia 1 DISC1 detectable. Mitochondria are the predominant site of DISC1 expression with additional nuclear, cytoplasmic, and actin-associated locations evident. Although the subcellular targeting of DISC1 is clearly complex, the association with mitochondria is of interest as many mitochondrial deficits have been reported in schizophrenia and other neuropsychiatric illnesses. Moreover, of the many cellular functions performed by mitochondria, their role in oxidative phosphorylation, calcium homeostasis, and apoptosis may hold particular relevance for the neuronal disturbances believed to be involved in the pathogenesis of schizophrenia.
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Compartimento Celular/genética , Mitocondrias/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Esquizofrenia/genética , Actinas/genética , Actinas/metabolismo , Animales , Química Encefálica/genética , Línea Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Metabolismo Energético/genética , Técnica del Anticuerpo Fluorescente , Hipocampo/metabolismo , Hipocampo/fisiopatología , Humanos , Mitocondrias/genética , Proteínas del Tejido Nervioso/genética , Neuronas/citología , Neuronas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/aislamiento & purificación , Roedores/genética , Roedores/metabolismo , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologíaRESUMEN
Inner centromere protein (INCENP) is a chromosomal passenger protein with an essential role in mitosis. At the metaphase/anaphase transition, some INCENP transfers from the centromeres to the central spindle; the remainder then transfers to the equatorial cortex prior to cleavage furrow formation. The molecular associations dictating INCENP behavior during mitosis are currently unknown. Here we show that targeting INCENP to the cleavage plane requires dynamic microtubules, but not F-actin. When microtubules are eliminated, INCENP is dispersed across the entire cell cortex. Yeast two-hybrid and in vitro binding data demonstrate that INCENP binds directly to beta-tubulin via a conserved domain encompassing residues 48-85. Furthermore, INCENP binds to microtubules polymerized from purified tubulin in vitro and appears to bundle microtubules when expressed in the interphase cytoplasm. These data indicate that INCENP is a microtubule-binding protein that targets to the equatorial cortex through interactions requiring microtubules.
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Proteínas Cromosómicas no Histona/metabolismo , Microtúbulos/metabolismo , Mitosis/fisiología , Tubulina (Proteína)/metabolismo , Actinas/metabolismo , Secuencias de Aminoácidos/fisiología , Anafase/fisiología , Animales , Sitios de Unión , Línea Celular , Pollos , Proteínas Cromosómicas no Histona/genética , Secuencia Conservada , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Metafase/fisiología , Mitosis/efectos de los fármacos , Paclitaxel/farmacología , Unión Proteica/fisiología , Estructura Terciaria de Proteína/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Tubulina (Proteína)/genética , Técnicas del Sistema de Dos HíbridosRESUMEN
Proper chromosome condensation requires the phosphorylation of histone and nonhistone chromatin proteins. We have used an in vitro chromosome assembly system based on Xenopus egg cytoplasmic extracts to study mitotic histone H3 phosphorylation. We identified a histone H3 Ser(10) kinase activity associated with isolated mitotic chromosomes. The histone H3 kinase was not affected by inhibitors of cyclin-dependent kinases, DNA-dependent protein kinase, p90(rsk), or cAMP-dependent protein kinase. The activity could be selectively eluted from mitotic chromosomes and immunoprecipitated by specific anti-X aurora-B/AIRK2 antibodies. This activity was regulated by phosphorylation. Treatment of X aurora-B immunoprecipitates with recombinant protein phosphatase 1 (PP1) inhibited kinase activity. The presence of PP1 on chromatin suggested that PP1 might directly regulate the X aurora-B associated kinase activity. Indeed, incubation of isolated interphase chromatin with the PP1-specific inhibitor I2 and ATP generated an H3 kinase activity that was also specifically immunoprecipitated by anti-X aurora-B antibodies. Nonetheless, we found that stimulation of histone H3 phosphorylation in interphase cytosol does not drive chromosome condensation or targeting of 13 S condensin to chromatin. In summary, the chromosome-associated mitotic histone H3 Ser(10) kinase is associated with X aurora-B and is inhibited directly in interphase chromatin by PP1.
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Histonas/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Aurora Quinasas , Cromatina/metabolismo , Activación Enzimática , Fosforilación , Proteína Fosfatasa 1 , Transducción de Señal , XenopusRESUMEN
We have begun to study the structural requirements for the binding of formyl peptides to their specific receptors. As an initial approach, we constructed C5a-formyl peptide receptor chimeras. Unique (and identical) restriction sites were introduced within the transmembrane domains of these receptors that allowed for the exchange of specific areas. Four types of chimeric receptors were generated. 1) The C5a receptor was progressively substituted by the formyl peptide receptor. 2) The formyl peptide receptor was progressively substituted by the C5a receptor. 3) Specific domains of the C5a receptor were substituted by the corresponding domain of the formyl peptide receptor. 4) Specific domains of the formyl peptide receptor were replaced by the same corresponding domain of the C5a receptor. Wild type and chimeric receptors were transfected into COS 7 cells and their ability to bind formyl peptide determined, taking into account efficiency of transfection and expression of chimeric protein. Based on these results, a ligand binding model is presented in which the second, third, and fourth extracellular (and/or their transmembrane) domains together with the first transmembrane domain form a ligand binding pocket for formyl peptides. It is proposed that the amino-terminal domain plays a role by presumably providing a "lid" to the pocket. The carboxyl-terminal cytoplasmic tail appears to modulate ligand binding by regulating receptor affinity.