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2.
Int J Sport Nutr Exerc Metab ; 32(3): 204-213, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35294923

RESUMEN

Dietary intake and physical activity impact performance and adaptation during training. The aims of this study were to compare energy and macronutrient intake during British Army Officer Cadet training with dietary guidelines and describe daily distribution of energy and macronutrient intake and estimated energy expenditure. Thirteen participants (seven women) were monitored during three discrete periods of military training for 9 days on-camp, 5 days of field exercise, and 9 days of a mixture of the two. Dietary intake was measured using researcher-led food weighing and food diaries, and energy expenditure was estimated from wrist-worn accelerometers. Energy intake was below guidelines for men (4,600 kcal/day) and women (3,500 kcal/day) during on-camp training (men = -16% and women = -9%), field exercise (men = -33% and women = -42%), and combined camp and field training (men and women both -34%). Carbohydrate intake of men and women were below guidelines (6 g·kg-1·day-1) during field exercise (men = -18% and women = -37%) and combined camp and field training (men = -33% and women = -39%), respectively. Protein intake was above guidelines (1.2 kcal·kg-1·day-1) for men and women during on-camp training (men = 48% and women = 39%) and was below guidelines during field exercise for women only (-27%). Energy and macronutrient intake during on-camp training centered around mealtimes with a discernible sleep/wake cycle for energy expenditure. During field exercise, energy and macronutrient intake were individually variable, and energy expenditure was high throughout the day and night. These findings could be used to inform evidenced-based interventions to change the amount and timing of energy and macronutrient intake around physical activity to optimize performance and adaptations during military training.


Asunto(s)
Personal Militar , Acondicionamiento Físico Humano , Ingestión de Alimentos , Ingestión de Energía , Metabolismo Energético , Ejercicio Físico , Femenino , Humanos , Masculino
6.
J Med Chem ; 62(14): 6540-6560, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31199640

RESUMEN

Tumors have evolved a variety of methods to reprogram conventional metabolic pathways to favor their own nutritional needs, including glutaminolysis, the first step of which is the hydrolysis of glutamine to glutamate by the amidohydrolase glutaminase 1 (GLS1). A GLS1 inhibitor could potentially target certain cancers by blocking the tumor cell's ability to produce glutamine-derived nutrients. Starting from the known GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide, we describe the medicinal chemistry evolution of a series from lipophilic inhibitors with suboptimal physicochemical and pharmacokinetic properties to cell potent examples with reduced molecular weight and lipophilicity, leading to compounds with greatly improved oral exposure that demonstrate in vivo target engagement accompanied by activity in relevant disease models.


Asunto(s)
Antineoplásicos/farmacología , Glutaminasa/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Piridazinas/farmacología , Tiadiazoles/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Disponibilidad Biológica , Línea Celular Tumoral , Descubrimiento de Drogas , Glutaminasa/metabolismo , Humanos , Masculino , Ratones SCID , Simulación del Acoplamiento Molecular , Neoplasias/metabolismo , Neoplasias/patología , Piridazinas/química , Piridazinas/farmacocinética , Piridazinas/uso terapéutico , Tiadiazoles/química , Tiadiazoles/farmacocinética , Tiadiazoles/uso terapéutico
7.
Oncotarget ; 10(27): 2586-2606, 2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-31080552

RESUMEN

Tumours defective in the DNA homologous recombination repair pathway can be effectively treated with poly (ADP-ribose) polymerase (PARP) inhibitors; these have proven effective in clinical trials in patients with BRCA gene function-defective cancers. However, resistance observed in both pre-clinical and clinical studies is likely to impact on this treatment strategy. Over-expression of phosphoglycoprotein (P-gp) has been previously suggested as a mechanism of resistance to the PARP inhibitor olaparib in mouse models of Brca1/2-mutant breast cancer. Here, we report that in a Brca2 model treated with olaparib, P-gp upregulation is observed but is not sufficient to confer resistance. Furthermore, resistant/relapsed tumours do not show substantial changes in PK/PD of olaparib, do not downregulate PARP1 or re-establish double stranded DNA break repair by homologous recombination, all previously suggested as mechanisms of resistance. However, resistance is strongly associated with epithelial-mesenchymal transition (EMT) and treatment-naïve tumours given a single dose of olaparib upregulate EMT markers within one hour. Therefore, in this model, olaparib resistance is likely a product of an as-yet unidentified mechanism associated with rapid transition to the mesenchymal phenotype.

8.
BMC Psychiatry ; 19(1): 1, 2019 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-30606141

RESUMEN

BACKGROUND: Research on the long-term mental health consequences of war and displacement among civilians who live in post-conflict countries is rare. The aim of this study was to examine the developmental trajectories and predictors of general psychological distress in three samples of Bosnian war survivors over an 11-year period. METHODS: In 1998/99, about three years after the war in Bosnia and Herzegovina, a representative sample of 299 adult Sarajevo citizens was examined in three subsamples: individuals who had stayed in Sarajevo throughout the siege, individuals who had been internally displaced, and refugees who had returned. Of the 138 study participants who could be located 11 years later, 100 were re-assessed (71%) using the Brief Symptom Inventory. RESULTS: Over time, psychological symptoms and general psychological distress decreased in those survivors who had stayed and increased in returnees. Former displaced persons did not show any significant changes. After controlling for other factors, cumulative trauma exposure before and during the war predicted general psychological distress at baseline. Eleven years later, higher trauma exposure during and after the war, returnee status, and more current stressors were all associated with higher levels of general psychological distress. CONCLUSIONS: Levels of psychological symptoms remained high in three subsamples of Bosnian war survivors. The differential symptom trajectories may correspond to distinct war experiences and contemporary stressors. Still, the cumulative effect of war traumata on mental distress persisted more than a decade after war and displacement, although the influence of current stressors seemed to increase over time.


Asunto(s)
Refugiados/psicología , Estrés Psicológico/psicología , Sobrevivientes/psicología , Guerra/psicología , Adolescente , Adulto , Anciano , Bosnia y Herzegovina , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
9.
Mol Cancer Ther ; 15(10): 2378-2387, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27439477

RESUMEN

Osimertinib (AZD9291) is a potent, selective, irreversible inhibitor of EGFR-sensitizing (exon 19 and L858R) and T790M-resistant mutation. In vivo, in the mouse, it is metabolized to an active des-methyl metabolite, AZ5104. To understand the therapeutic potential in patients, this study aimed to assess the relationship between osimertinib pharmacokinetics, the pharmacokinetics of the active metabolite, the pharmacodynamics of phosphorylated EGFR reduction, and efficacy in mouse xenograft models of EGFR-driven cancers, including two NSCLC lines. Osimertinib was dosed in xenografted models of EGFR-driven cancers. In one set of experiments, changes in phosphorylated EGFR were measured to confirm target engagement. In a second set of efficacy studies, the resulting changes in tumor volume over time after repeat dosing of osimertinib were observed. To account for the contributions of both molecules, a mathematical modeling approach was taken to integrate the resulting datasets. The model was able to describe the pharmacokinetics, pharmacodynamics, and efficacy in A431, PC9, and NCI-H1975 xenografts, with the differences in sensitivity described by the varying potency against wild-type, sensitizing, and T790M-mutant EGFR and the phosphorylated EGFR reduction required to reduce tumor volume. It was inferred that recovery of pEGFR is slower after chronic dosing due to reduced resynthesis. It was predicted and further demonstrated that although inhibition is irreversible, the resynthesis of EGFR is such that infrequent intermittent dosing is not as efficacious as once daily dosing. Mol Cancer Ther; 15(10); 2378-87. ©2016 AACR.


Asunto(s)
Antineoplásicos/farmacocinética , Receptores ErbB/antagonistas & inhibidores , Piperazinas/farmacología , Inhibidores de Proteínas Quinasas/farmacocinética , Acrilamidas , Algoritmos , Compuestos de Anilina , Animales , Antineoplásicos/química , Línea Celular Tumoral , Modelos Animales de Enfermedad , Receptores ErbB/química , Humanos , Ratones , Modelos Biológicos , Piperazinas/química , Inhibidores de Proteínas Quinasas/química , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Cancer Res ; 76(11): 3307-18, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27020862

RESUMEN

Fulvestrant is an estrogen receptor (ER) antagonist administered to breast cancer patients by monthly intramuscular injection. Given its present limitations of dosing and route of administration, a more flexible orally available compound has been sought to pursue the potential benefits of this drug in patients with advanced metastatic disease. Here we report the identification and characterization of AZD9496, a nonsteroidal small-molecule inhibitor of ERα, which is a potent and selective antagonist and downregulator of ERα in vitro and in vivo in ER-positive models of breast cancer. Significant tumor growth inhibition was observed as low as 0.5 mg/kg dose in the estrogen-dependent MCF-7 xenograft model, where this effect was accompanied by a dose-dependent decrease in PR protein levels, demonstrating potent antagonist activity. Combining AZD9496 with PI3K pathway and CDK4/6 inhibitors led to further growth-inhibitory effects compared with monotherapy alone. Tumor regressions were also seen in a long-term estrogen-deprived breast model, where significant downregulation of ERα protein was observed. AZD9496 bound and downregulated clinically relevant ESR1 mutants in vitro and inhibited tumor growth in an ESR1-mutant patient-derived xenograft model that included a D538G mutation. Collectively, the pharmacologic evidence showed that AZD9496 is an oral, nonsteroidal, selective estrogen receptor antagonist and downregulator in ER(+) breast cells that could provide meaningful benefit to ER(+) breast cancer patients. AZD9496 is currently being evaluated in a phase I clinical trial. Cancer Res; 76(11); 3307-18. ©2016 AACR.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Cinamatos/farmacología , Moduladores de los Receptores de Estrógeno/farmacología , Receptor alfa de Estrógeno/antagonistas & inhibidores , Receptor alfa de Estrógeno/genética , Indoles/farmacología , Mutación/genética , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Cinamatos/administración & dosificación , Evaluación Preclínica de Medicamentos , Moduladores de los Receptores de Estrógeno/administración & dosificación , Receptor alfa de Estrógeno/química , Femenino , Humanos , Indoles/administración & dosificación , Ratones , Ratones Endogámicos NOD , Ratones SCID , Conformación Proteica , Ratas , Células Tumorales Cultivadas , Útero/metabolismo , Útero/patología , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Mol Cancer Ther ; 14(1): 48-58, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25398829

RESUMEN

Loss of PTEN protein results in upregulation of the PI3K/AKT pathway, which appears dependent on the PI3Kß isoform. Inhibitors of PI3Kß have potential to reduce growth of tumors in which loss of PTEN drives tumor progression. We have developed a small-molecule inhibitor of PI3Kß and PI3Kδ (AZD8186) and assessed its antitumor activity across a panel of cell lines. We have then explored the antitumor effects as single agent and in combination with docetaxel in triple-negative breast (TNBC) and prostate cancer models. In vitro, AZD8186 inhibited growth of a range of cell lines. Sensitivity was associated with inhibition of the AKT pathway. Cells sensitive to AZD8186 (GI50 < 1 µmol/L) are enriched for, but not exclusively associated with, PTEN deficiency. In vivo, AZD8186 inhibits PI3K pathway biomarkers in prostate and TNBC tumors. Scheduling treatment with AZD8186 shows antitumor activity required only intermittent exposure, and that increased tumor control is achieved when AZD8186 is used in combination with docetaxel. AZD8186 is a potent inhibitor of PI3Kß with activity against PI3Kδ signaling, and has potential to reduce growth of tumors dependent on dysregulated PTEN for growth. Moreover, AZD8186 can be combined with docetaxel, a chemotherapy commonly used to treat advanced TBNC and prostate tumors. The ability to schedule AZD8186 and maintain efficacy offers opportunity to combine AZD8186 more effectively with other drugs.


Asunto(s)
Compuestos de Anilina/administración & dosificación , Antineoplásicos/administración & dosificación , Cromonas/administración & dosificación , Inhibidores de las Quinasa Fosfoinosítidos-3 , Neoplasias de la Próstata/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Taxoides/administración & dosificación , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Compuestos de Anilina/farmacología , Animales , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromonas/farmacología , Docetaxel , Sinergismo Farmacológico , Femenino , Humanos , Masculino , Ratones , Fosfohidrolasa PTEN/deficiencia , Neoplasias de la Próstata/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Clin Psychol Psychother ; 22(6): 604-18, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25256361

RESUMEN

OBJECTIVE: In this trial, we compared the relative efficacy of dialogical exposure group treatment using Gestalt empty-chair method with a supportive group in the treatment of symptoms stemming from traumatic loss in a post-war society. METHODS: One-hundred and nineteen women whose husbands were either killed or registered as missing during the war in Bosnia and Herzegovina were quasi-randomized to seven sessions of group treatment with dialogical exposure or to an active control condition. RESULTS: Both interventions resulted in significant improvement from baseline to post-treatment for both kinds of loss, in terms of post-traumatic symptoms, general mental health and grief reactions, with the exception of depression and traumatic grief in the control condition. Regarding mean effect sizes (Cohen's d), pre-treatment to post-treatment improvements were moderate (d = 0.56) for the dialogical exposure group and small (d = 0.34) for the supportive group. Treatment gains were maintained at least until the 1-year follow-up. In controlled comparisons, dialogical exposure was superior concerning traumatic grief (Cohen's d = 0.37) and post-traumatic avoidance (d = 0.73) at post-treatment. CONCLUSIONS: Results show that short-term dialogical exposure group treatment was moderately effective in treating traumatically bereaved women. KEY PRACTITIONER MESSAGE: Research attests to high levels of symptoms among post-war civil populations, in particular, when a loved one was killed, which can lead not only to trauma reactions but also to severe separation distress. Grieving the loss of a loved one is hampered if the death remains unconfirmed. Unconfirmed loss could be conceptualized as unfinished business in terms of Gestalt therapy, which offers empty-chair dialogue for resolving unfinished business and grief. Dialogical exposure therapy (DET) supports the client in gaining awareness of and expressing his or her inner dialogues concerning the traumatic event, using Gestalt empty-chair method. Short-term DET was effective in treating traumatically bereaved women but showed little additional effects in comparison with a supportive group treatment, so further research is warranted.


Asunto(s)
Aflicción , Terapia Implosiva/métodos , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapia , Adulto , Bosnia y Herzegovina , Femenino , Humanos , Persona de Mediana Edad , Resultado del Tratamiento , Guerra
13.
Clin Trials ; 11(2): 159-66, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24686106

RESUMEN

BACKGROUND: and purpose Participant recruitment is central to all clinical trials. Any delay in recruitment affects the completion and ultimate success of the trial. We report our experience with patient screening and randomization in CombiRx, which may inform the design of other trials. CombiRx was a multicenter, phase III, double-blind, randomized clinical trial comparing the combined use of interferon beta-1a and glatiramer acetate to either agent alone in patients with relapsing-remitting multiple sclerosis (RRMS). This trial was launched in January 2005 in 69 centers in the United States and Canada under a co-operative agreement with the National Institute of Neurological Disorders and Stroke (NINDS). The goal was to recruit 1000 patients over 1.5 years after a 6-month start-up period. Instead, the investigators required 4.25 years to enroll 1008 patients. METHODS: During this trial, we assessed the effectiveness of various recruitment strategies, utility of rescreening prior screen failures, and potential factors and strategies used in study conduct, research, and infrastructure, all of which affected recruitment of participants and ultimately time to completion of CombiRx. We particularly were interested in the variability in time to site initiation between academic centers and private practice sites. RESULTS: Physicians who were directly involved in the medical care of patients with RRMS were the primary source of patients recruited to CombiRx. A flexible study design that allowed for rescreening of the initial screen failures after a period of time was useful due to the relapsing/remitting course of the disease. Academic centers took longer to implement the trial than the private practice centers, but once sites were approved for enrollment, there was no important difference in the number of participants enrolled. LIMITATIONS: The CombiRx trial was conducted during a period when multiple new medications were being tested, thus affecting the pace of recruitment and limiting ability to generalize our experiences. However, the lessons we learned about process are relevant. CONCLUSION: Participants can be enrolled successfully in a clinical trial for RRMS, but factors affecting the time to achieve the requirements needed to start screening can be unpredictable and problematic. Prospective planning by the sponsors and investigators, use of central institutional review boards (IRBs), master trial agreements and secure remote desktop access to the trial database may expedite trial implementation and participant recruitment. A good scientific research question with flexible study design and active involvement of the clinicians are important factors driving recruitment. Clinical trials can be implemented successfully both in private practices and at academic centers, a consideration when selecting sites.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Interferón beta/uso terapéutico , Estudios Multicéntricos como Asunto/métodos , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Selección de Paciente , Péptidos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Ensayos Clínicos Fase III como Asunto/métodos , Método Doble Ciego , Quimioterapia Combinada , Acetato de Glatiramer , Humanos , Interferón beta-1a
14.
PLoS One ; 8(6): e66003, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23840389

RESUMEN

Pre-clinical models of tumour biology often rely on propagating human tumour cells in a mouse. In order to gain insight into the alignment of these models to human disease segments or investigate the effects of different therapeutics, approaches such as PCR or array based expression profiling are often employed despite suffering from biased transcript coverage, and a requirement for specialist experimental protocols to separate tumour and host signals. Here, we describe a computational strategy to profile transcript expression in both the tumour and host compartments of pre-clinical xenograft models from the same RNA sample using RNA-Seq. Key to this strategy is a species-specific mapping approach that removes the need for manipulation of the RNA population, customised sequencing protocols, or prior knowledge of the species component ratio. The method demonstrates comparable performance to species-specific RT-qPCR and a standard microarray platform, and allowed us to quantify gene expression changes in both the tumour and host tissue following treatment with cediranib, a potent vascular endothelial growth factor receptor tyrosine kinase inhibitor, including the reduction of multiple murine transcripts associated with endothelium or vessels, and an increase in genes associated with the inflammatory response in response to cediranib. In the human compartment, we observed a robust induction of hypoxia genes and a reduction in cell cycle associated transcripts. In conclusion, the study establishes that RNA-Seq can be applied to pre-clinical models to gain deeper understanding of model characteristics and compound mechanism of action, and to identify both tumour and host biomarkers.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Redes Reguladoras de Genes/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Quinazolinas/administración & dosificación , Análisis de Secuencia de ARN/métodos , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Ciclo Celular/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Biología Computacional , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Pulmonares/genética , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Especificidad de la Especie , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Cochrane Database Syst Rev ; (6): CD007274, 2012 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-22696368

RESUMEN

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is an uncomfortable therapeutic procedure that cannot be performed without adequate sedation or general anaesthesia. A considerable number of ERCPs are performed annually in the UK (at least 48,000) and many more worldwide. OBJECTIVES: The primary objective of our review was to evaluate and compare the efficacy and safety of sedative or anaesthetic techniques used to facilitate the procedure of ERCP in adult (age > 18 years) patients. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 8); MEDLINE (1950 to September 2011); EMBASE (1950 to September 2011); CINAHL, Web of Science and LILACS (all to September 2011). We searched for additional studies drawn from reference lists of retrieved trial materials and review articles and conference proceedings. SELECTION CRITERIA: We considered all randomized or quasi-randomized controlled studies where the main procedures performed were ERCPs. The three interventions we searched for were (1) conscious sedation (using midazolam plus opioid) versus deep sedation (using propofol); (2) conscious sedation versus general anaesthesia; and (3) deep sedation versus general anaesthesia. We considered all studies regardless of which healthcare professional administered the sedation. DATA COLLECTION AND ANALYSIS: We reviewed 124 papers and identified four randomized trials (with a total of 510 participants) that compared the use of conscious sedation using midazolam and meperidine with deep sedation using propofol in patients undergoing ERCP procedures. All sedation was administered by non-anaesthetic personnel. Due to the clinical heterogeneity of the studies we decided to review the papers from a narrative perspective as opposed to a full meta-analysis. Our primary outcome measures included mortality, major complications and inability to complete the procedure due to sedation-related problems. Secondary outcomes encompassed sedation efficacy and recovery. MAIN RESULTS: No immediate mortality was reported. There was no significant difference in serious cardio-respiratory complications suffered by patients in either sedation group. Failure to complete the procedure due to sedation-related problems was reported in one study. Three studies found faster and better recovery in patients receiving propofol for their ERCP procedures. Study protocols regarding use of supplemental oxygen, intravenous fluid administration and capnography monitoring varied considerably. The studies showed either moderate or high risk of bias. AUTHORS' CONCLUSIONS: Results from individual studies suggested that patients have a better recovery profile after propofol sedation for ERCP procedures than after midazolam and meperidine sedation. As there was no difference between the two sedation techniques as regards safety, propofol sedation is probably preferred for patients undergoing ERCP procedures. However, in all of the studies that were identified only non-anaesthesia personnel were involved in administering the sedation. It would be helpful if further research was conducted where anaesthesia personnel were involved in the administration of sedation for ERCP procedures. This would clarify the extent to which anaesthesia personnel should be involved in the administration of propofol sedation.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Hipnóticos y Sedantes/administración & dosificación , Meperidina/administración & dosificación , Midazolam/administración & dosificación , Propofol/administración & dosificación , Periodo de Recuperación de la Anestesia , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Sedación Consciente/métodos , Humanos , Hipnóticos y Sedantes/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Angiogenesis ; 15(4): 555-68, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22644562

RESUMEN

Human tumour xenografts have commonly been used to explore the mechanisms of tumour angiogenesis and the interaction of tumour cells with their microenvironment, as well as predict potential utility of anti-angiogenic inhibitors across different tumour types. To investigate how well human tumour xenografts can be used to differentiate the effects of stromal targeting agents we performed a comparative assessment of the murine angiogenic response across a panel of pre-clinical tumour xenografts. By analysing a panel of 22 tumour xenografts with a range of vascular morphologies, micro-vessel densities and levels of fibroblast and inflammatory infiltrate, we have examined the relationship between angiogenic stroma and human tumour models. These models were studied using a combination of immunohistochemistry and species specific mRNA profiling to differentiate the tumour and stromal transcript mRNA profiles. Principal Component Analysis (PCA) and regression analysis was used to investigate the transcriptional relationships between the individual models and the correlation with the stromal architecture. We found the human tumour cell expressed factors to be independent of the murine host responses such as microvessel density, and fibroblast or macrophage cellular infiltrate. Moreover mRNA profiling of the mouse stroma suggested that the host response to the different tumours was relatively uniform despite differences in stromal structures within the tumour. Supporting this, models with different stromal compositions responded similarly to cediranib, a small molecule inhibitor of VEGF signalling. The data indicate that although the angiogenic response to the tumour results in reproducible stromal architectures, these responses are not differentiated at the level of gene expression.


Asunto(s)
Vasos Sanguíneos/crecimiento & desarrollo , Diferenciación Celular , Expresión Génica , Neovascularización Patológica/genética , Células del Estroma/metabolismo , Secuencia de Bases , Cartilla de ADN , Humanos , Inmunohistoquímica , Microfluídica , Trasplante Heterólogo
18.
Hum Mutat ; 33(1): 100-3, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22009941

RESUMEN

Mutations in the chromatin remodeling gene ARID1A have recently been identified in the majority of ovarian clear cell carcinomas (OCCCs). To determine the prevalence of mutations in other tumor types, we evaluated 759 malignant neoplasms including those of the pancreas, breast, colon, stomach, lung, prostate, brain, and blood (leukemias). We identified truncating mutations in 6% of the neoplasms studied; nontruncating somatic mutations were identified in an additional 0.4% of neoplasms. Mutations were most commonly found in gastrointestinal samples with 12 of 119 (10%) colorectal and 10 of 100 (10%) gastric neoplasms, respectively, harboring changes. More than half of the mutated colorectal and gastric cancers displayed microsatellite instability (MSI) and the mutations in these tumors were out-of-frame insertions or deletions at mononucleotide repeats. Mutations were also identified in 2-8% of tumors of the pancreas, breast, brain (medulloblastomas), prostate, and lung, and none of these tumors displayed MSI. These findings suggest that the aberrant chromatin remodeling consequent to ARID1A inactivation contributes to a variety of different types of neoplasms.


Asunto(s)
Adenocarcinoma de Células Claras/genética , Cromatina/genética , Neoplasias Colorrectales/genética , Mutación del Sistema de Lectura , Proteínas Nucleares/genética , Neoplasias Gástricas/genética , Factores de Transcripción/genética , Adenocarcinoma de Células Claras/patología , Secuencia de Bases , Mama/metabolismo , Mama/patología , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina , Colon/metabolismo , Colon/patología , Neoplasias Colorrectales/patología , Proteínas de Unión al ADN , Femenino , Mucosa Gástrica/metabolismo , Humanos , Masculino , Inestabilidad de Microsatélites , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Páncreas/metabolismo , Páncreas/patología , Estómago/patología , Neoplasias Gástricas/patología
19.
Toxicol Pathol ; 39(6): 916-24, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21859884

RESUMEN

Aberrant signaling by transforming growth factor-ß (TGF-ß) and its type I (ALK5) receptor has been implicated in a number of human diseases and this pathway is considered a potential target for therapeutic intervention. Transforming growth factor-ß signaling via ALK5 plays a critical role during heart development, but the role of ALK5 in the adult heart is poorly understood. In the current study, the preclinical toxicology of ALK5 inhibitors from two different chemistry scaffolds was explored. Ten-week-old female Han Wistar rats received test compounds by the oral route for three to seven days. Both compounds induced histopathologic heart valve lesions characterized by hemorrhage, inflammation, degeneration, and proliferation of valvular interstitial cells. The pathology was observed in all animals, at all doses tested, and occurred in all four heart valves. Immunohistochemical analysis of ALK5 in rat hearts revealed expression in the valves, but not in the myocardium. Compared to control animals, protein levels of ALK5 were unchanged in the heart valves of treated animals. We also observed a physeal dysplasia in the femoro-tibial joint of rats treated with ALK5 inhibitors, a finding consistent with a pharmacological effect described previously with ALK5 inhibitors. Overall, these findings suggest that TGF-ß signaling via ALK5 plays a critical role in maintaining heart valve integrity.


Asunto(s)
Válvulas Cardíacas/patología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Administración Oral , Animales , Evaluación Preclínica de Medicamentos , Femenino , Válvulas Cardíacas/efectos de los fármacos , Inmunohistoquímica/métodos , Proteínas Serina-Treonina Quinasas/genética , Ratas , Ratas Wistar , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/genética , Transducción de Señal , Factor de Crecimiento Transformador beta/genética
20.
Int J Biochem Cell Biol ; 43(4): 604-12, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21187158

RESUMEN

TGFß signals through serine/threonine kinase receptors and intracellular Smad transcription factors. An important regulatory step involves ubiquitination of Smads and/or TGFß receptors by specific ubiquitin ligases, in a process that can be reversed by the deubiquitinating enzyme UCH37. Here, to explore the physiological role of UCH37 in TGFß signalling we have generated stable and inducible HaCAT keratinocyte and Colo-357 pancreatic carcinoma cell lines mis-expressing UCH37. We show that UCH37 knockdown significantly inhibits the activity of a TGFß-dependent gene reporter and selectively decreases levels of some TGFß-dependent target genes, notably p21 and PAI-1, but only during the early phase of TGFß receptor activation. Interestingly, UCH37 knockdown in Colo-357 cells had no effect on TGFß-dependent cell proliferation and epithelial-mesenchymal transition, yet significantly impaired cell migration. Collectively, our data indicate that UCH37 sustains early TGFß pathway activation kinetics that determines threshold-specific gene expression patterns, and that opposing actions of ubiquitin ligases and deubiquitinases influences distinct biological TGFß-dependent biological responses. Moreover, we suggest that UCH37 could represent a viable target for novel and selective cancer therapeutics.


Asunto(s)
Carboxipeptidasas/metabolismo , Movimiento Celular , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal , Carboxipeptidasas/deficiencia , Carboxipeptidasas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Técnicas de Silenciamiento del Gen , Genes Reporteros/genética , Humanos , Luciferasas/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Transducción de Señal/genética , Proteína smad3/metabolismo , Transcripción Genética/genética
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