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1.
Nature ; 582(7810): 134, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32483375

RESUMEN

A Retraction to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nature ; 570(7761): E51, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31127195

RESUMEN

Change history: In this Letter, the citation to 'Fig. 4e, f' in the main text should be 'Fig. 3e, f'. This has not been corrected online.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38918313

RESUMEN

OBJECTIVES: The aim of this study was to examine the association between Medicaid dental benefits for pregnant people and dental care use among very young children in Medicaid. We hypothesized that children living in states with more generous dental benefits for Medicaid-enrolled pregnant people would be more likely to have a recent dental visit. METHODS: This national cross-sectional study used pooled 2017-2019 data from the National Survey of Children's Health, as well as state Medicaid policy data. The study sample included children aged 0-2 enrolled in Medicaid. Multivariable logistic regression models estimated the association between Medicaid dental benefit generosity for pregnant people and the child having a dental visit in the past year. RESULTS: Children in states with emergency-only dental coverage for pregnant people were 2.5 times as likely to have had a dental visit than children in states with extensive coverage (OR 2.48, 95% CI 1.35-4.53). In supplemental analyses excluding children living in Texas, there was no longer an association between dental coverage for pregnant people and dental utilization among young children (OR 1.52, 95% CI 0.82-2.83). CONCLUSIONS FOR PRACTICE: Young children in states that provided emergency-only dental benefits for pregnant people in Medicaid had significantly higher odds of dental utilization than young children in states with more generous dental benefits for pregnant people. This relationship disappeared after excluding the state Texas, which had the highest rate of child dental utilization in the country and provided emergency-only dental benefits for pregnant people in Medicaid.

4.
BMC Med Educ ; 23(1): 123, 2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36804003

RESUMEN

BACKGROUND: Empathic care is considered extremely important by patients and providers alike but there is still an ample need for assessing empathy among healthcare students and professionals and identifying appropriate educational interventions to improve it. This study aims to assess empathy levels and associated factors among students at different healthcare colleges at the University of Iowa. METHODS: An online survey was delivered to healthcare students, including nursing, pharmacy, dental, and medical colleges (IRB ID #202,003,636). The cross-sectional survey included background questions, probing questions, college-specific questions, and the Jefferson Scale of Empathy-Health Professionals Student version (JSPE-HPS). To examine bivariate associations, Kruskal Wallis and Wilcoxon rank sum tests were used. A linear model with no transformation was used in the multivariable analysis. RESULTS: Three hundred students responded to the survey. Overall JSPE-HPS score was 116 (± 11.7), consistent with other healthcare professional samples. There was no significant difference in JSPE-HPS score among the different colleges (P = 0.532). CONCLUSION: Controlling for other variables in the linear model, healthcare students' view of their faculty's empathy toward patients and students' self-reported empathy levels were significantly associated with students' JSPE-HPS scores.


Asunto(s)
Actitud del Personal de Salud , Estudiantes de Medicina , Humanos , Estudios Transversales , Empatía , Universidades , Encuestas y Cuestionarios
5.
Nature ; 539(7627): 112-117, 2016 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-27595394

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is characterized by inactivation of the von Hippel-Lindau tumour suppressor gene (VHL). Because no other gene is mutated as frequently in ccRCC and VHL mutations are truncal, VHL inactivation is regarded as the governing event. VHL loss activates the HIF-2 transcription factor, and constitutive HIF-2 activity restores tumorigenesis in VHL-reconstituted ccRCC cells. HIF-2 has been implicated in angiogenesis and multiple other processes, but angiogenesis is the main target of drugs such as the tyrosine kinase inhibitor sunitinib. HIF-2 has been regarded as undruggable. Here we use a tumourgraft/patient-derived xenograft platform to evaluate PT2399, a selective HIF-2 antagonist that was identified using a structure-based design approach. PT2399 dissociated HIF-2 (an obligatory heterodimer of HIF-2α-HIF-1ß) in human ccRCC cells and suppressed tumorigenesis in 56% (10 out of 18) of such lines. PT2399 had greater activity than sunitinib, was active in sunitinib-progressing tumours, and was better tolerated. Unexpectedly, some VHL-mutant ccRCCs were resistant to PT2399. Resistance occurred despite HIF-2 dissociation in tumours and evidence of Hif-2 inhibition in the mouse, as determined by suppression of circulating erythropoietin, a HIF-2 target and possible pharmacodynamic marker. We identified a HIF-2-dependent gene signature in sensitive tumours. Gene expression was largely unaffected by PT2399 in resistant tumours, illustrating the specificity of the drug. Sensitive tumours exhibited a distinguishing gene expression signature and generally higher levels of HIF-2α. Prolonged PT2399 treatment led to resistance. We identified binding site and second site suppressor mutations in HIF-2α and HIF-1ß, respectively. Both mutations preserved HIF-2 dimers despite treatment with PT2399. Finally, an extensively pretreated patient whose tumour had given rise to a sensitive tumourgraft showed disease control for more than 11 months when treated with a close analogue of PT2399, PT2385. We validate HIF-2 as a target in ccRCC, show that some ccRCCs are HIF-2 independent, and set the stage for biomarker-driven clinical trials.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/metabolismo , Indanos/farmacología , Indanos/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , Sulfonas/farmacología , Sulfonas/uso terapéutico , Animales , Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Sitios de Unión , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Transformación Celular Neoplásica , Resistencia a Antineoplásicos/efectos de los fármacos , Eritropoyetina/antagonistas & inhibidores , Eritropoyetina/sangre , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Indanos/administración & dosificación , Indoles/farmacología , Indoles/uso terapéutico , Neoplasias Renales/genética , Neoplasias Renales/patología , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Terapia Molecular Dirigida , Mutación , Pirroles/farmacología , Pirroles/uso terapéutico , Reproducibilidad de los Resultados , Sulfonas/administración & dosificación , Sunitinib , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Clin Oral Implants Res ; 32(7): 871-880, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33949022

RESUMEN

OBJECTIVE: To evaluate the influence of surgery start time (SST) and other patient- and therapy-related variables on the risk for early implant failure (EIF) in an academic setting. MATERIAL AND METHODS: Data were extracted from the electronic health records of 61 patients who had at least one EIF and 140 age- and gender-matched, randomly selected, non-EIF controls. Bivariate and multivariable analyses were performed to identify relevant associations between EIF and different variables, such as SST. RESULTS: Incidence of EIF was not significantly associated with SST (HR: 1.9 for afternoon implant placement, 95% CI: 0.9-3.9; p = .105). Other factors that were associated with a significantly increased risk for EIF in a multivariable model were pre-placement ridge augmentation (HR: 7.5, 95% CI: 2.2-25.1; p = .001), intra-operative complications (HR: 5.9, 95% CI: 2.2-16.3; p < .001), simultaneous soft tissue grafting (HR: 5.03, 95% CI: 1.3-19.5; p = .020), simultaneous bone grafting (HR: 3.7, 95% CI: 1.6-8.8; p = .002), and placement with sedation (HR: 3.4, 95% CI: 1.5-7.5; p = .002). CONCLUSIONS: While SST was not associated with the occurrence of EIF in our cohort, other variables, such as ridge augmentation prior to implant placement, simultaneous bone or soft tissue grafting, intra-operative complications, implant placement with sedation, and number of implants in the oral cavity, were associated with an increased risk for this adverse event.


Asunto(s)
Aumento de la Cresta Alveolar , Implantes Dentales , Trasplante Óseo , Estudios de Casos y Controles , Implantación Dental Endoósea/efectos adversos , Humanos , Boca
7.
8.
Nature ; 512(7515): 431-5, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25043055

RESUMEN

Bone-resorbing osteoclasts significantly contribute to osteoporosis and bone metastases of cancer. MicroRNAs play important roles in physiology and disease, and present tremendous therapeutic potential. Nonetheless, how microRNAs regulate skeletal biology is underexplored. Here we identify miR-34a as a novel and critical suppressor of osteoclastogenesis, bone resorption and the bone metastatic niche. miR-34a is downregulated during osteoclast differentiation. Osteoclastic miR-34a-overexpressing transgenic mice exhibit lower bone resorption and higher bone mass. Conversely, miR-34a knockout and heterozygous mice exhibit elevated bone resorption and reduced bone mass. Consequently, ovariectomy-induced osteoporosis, as well as bone metastasis of breast and skin cancers, are diminished in osteoclastic miR-34a transgenic mice, and can be effectively attenuated by miR-34a nanoparticle treatment. Mechanistically, we identify transforming growth factor-ß-induced factor 2 (Tgif2) as an essential direct miR-34a target that is pro-osteoclastogenic. Tgif2 deletion reduces bone resorption and abolishes miR-34a regulation. Together, using mouse genetic, pharmacological and disease models, we reveal miR-34a as a key osteoclast suppressor and a potential therapeutic strategy to confer skeletal protection and ameliorate bone metastasis of cancers.


Asunto(s)
Neoplasias Óseas/prevención & control , Neoplasias Óseas/secundario , Diferenciación Celular/genética , MicroARNs/genética , Osteoclastos/patología , Osteoporosis/prevención & control , Proteínas Represoras/deficiencia , Animales , Secuencia de Bases , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/genética , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Eliminación de Gen , Proteínas de Homeodominio/antagonistas & inhibidores , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Masculino , Neoplasias Mamarias Animales/patología , Ratones , Ratones Transgénicos , MicroARNs/farmacología , MicroARNs/uso terapéutico , Trasplante de Neoplasias , Tamaño de los Órganos/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteoporosis/genética , Osteoporosis/patología , Ovariectomía , Proteínas Represoras/antagonistas & inhibidores , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Neoplasias Cutáneas/patología , Transgenes , Ensayos Antitumor por Modelo de Xenoinjerto
9.
PLoS Genet ; 13(3): e1006650, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28273073

RESUMEN

Hepatocellular carcinoma (HCC) is the fifth most common solid tumor in the world and the third leading cause of cancer-associated deaths. A Sleeping Beauty-mediated transposon mutagenesis screen previously identified mutations that cooperate with MYC to accelerate liver tumorigenesis. This revealed a tumor suppressor role for Steroid Receptor Coactivator 2/Nuclear Receptor Coactivator 2 (Src-2/Ncoa2) in liver cancer. In contrast, SRC-2 promotes survival and metastasis in prostate cancer cells, suggesting a tissue-specific and context-dependent role for SRC-2 in tumorigenesis. To determine if genetic loss of SRC-2 is sufficient to accelerate MYC-mediated liver tumorigenesis, we bred Src-2-/- mice with a MYC-induced liver tumor model and observed a significant increase in liver tumor burden. RNA sequencing of liver tumors and in vivo chromatin immunoprecipitation assays revealed a set of direct target genes that are bound by SRC-2 and exhibit downregulated expression in Src-2-/- liver tumors. We demonstrate that activation of SHP (Small Heterodimer Partner), DKK4 (Dickkopf-4), and CADM4 (Cell Adhesion Molecule 4) by SRC-2 suppresses tumorigenesis in vitro and in vivo. These studies suggest that SRC-2 may exhibit oncogenic or tumor suppressor activity depending on the target genes and nuclear receptors that are expressed in distinct tissues and illuminate the mechanisms of tumor suppression by SRC-2 in liver.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Coactivador 2 del Receptor Nuclear/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Alelos , Animales , Antineoplásicos/química , Carcinogénesis , Carcinoma Hepatocelular/genética , Moléculas de Adhesión Celular/metabolismo , Proliferación Celular , Supervivencia Celular , Inmunoprecipitación de Cromatina , Elementos Transponibles de ADN , Femenino , Eliminación de Gen , Células Hep G2 , Humanos , Inmunoglobulinas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Hepáticas/genética , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Mutagénesis , Metástasis de la Neoplasia , Trasplante de Neoplasias , Coactivador 2 del Receptor Nuclear/genética , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Análisis de Secuencia de ARN
10.
Cancer ; 124(16): 3339-3345, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29975406

RESUMEN

BACKGROUND: Phase I cancer trials increasingly incorporate dose-expansion cohorts (DECs), reflecting a growing demand to acquire more information about investigational drugs. Protocols commonly fail to provide a sample-size justification or analysis plan for the DEC. In this study, we develop a statistical framework for the design of DECs. METHODS: We assume the maximum tolerated dose (MTD) for the investigational drug has been identified in the dose-escalation stage of the trial. We use the 80% lower confidence bound and the 90% upper confidence bound for the response and toxicity rates, respectively, as decision thresholds for the dose-expansion stage. We calculate the operating characteristics with reference to prespecified minimum effective response rates and maximum safe DLT rates. RESULTS: We apply our framework to specify a system of DEC plans. The design comprises three components: 1) the number of subjects enrolled at the MTD, 2) the minimum number of responses necessary to indicate provisional drug efficacy, and 3) the maximum number of dose-limiting toxicities (DLTs) permitted to indicate drug safety. We demonstrate our method in an application to a cancer immunotherapy trial. CONCLUSIONS: Our simple and practical tool enables creation of DEC designs that appropriately address the safety and efficacy objectives of the trial.


Asunto(s)
Ensayos Clínicos Fase I como Asunto/estadística & datos numéricos , Neoplasias/epidemiología , Proyectos de Investigación/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Humanos , Dosis Máxima Tolerada , Modelos Estadísticos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Tamaño de la Muestra
11.
EMBO J ; 33(17): 1960-76, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25024437

RESUMEN

The antimitotic anti-cancer drugs, including taxol, perturb spindle dynamics, and induce prolonged, spindle checkpoint-dependent mitotic arrest in cancer cells. These cells then either undergo apoptosis triggered by the intrinsic mitochondrial pathway or exit mitosis without proper cell division in an adaptation pathway. Using a genome-wide small interfering RNA (siRNA) screen in taxol-treated HeLa cells, we systematically identify components of the mitotic apoptosis and adaptation pathways. We show that the Mad2 inhibitor p31(comet) actively promotes mitotic adaptation through cyclin B1 degradation and has a minor separate function in suppressing apoptosis. Conversely, the pro-apoptotic Bcl2 family member, Noxa, is a critical initiator of mitotic cell death. Unexpectedly, the upstream components of the mitochondrial apoptosis pathway and the mitochondrial fission protein Drp1 contribute to mitotic adaption. Our results reveal crosstalk between the apoptosis and adaptation pathways during mitotic arrest.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Mitosis , Paclitaxel/farmacología , ARN Interferente Pequeño/análisis , Adaptación Fisiológica , Perfilación de la Expresión Génica , Células HeLa , Humanos , ARN Interferente Pequeño/genética
12.
Ann Surg ; 268(1): 151-157, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-28486387

RESUMEN

OBJECTIVE: To compare the perioperative outcomes of minimally invasive pancreaticoduodenectomy (MIPD) in comparison with open pancreaticoduodenectomy (OPD) in a national cohort of patients. BACKGROUND: Limited well-controlled studies exist comparing perioperative outcomes between MIPD and OPD. METHODS: Patients who underwent MIPD and OPD were abstracted from the 2014 to 2015 pancreas-targeted American College of Surgeons National Surgical Quality Improvement Program. OPD and MIPD patients were matched 3:1 using propensity score, and perioperative outcomes were compared. RESULTS: A total of 4484 patients were identified with 334 (7.4%) undergoing MIPD. MIPD patients were younger, more likely to be White, and had a lower rate of weight loss. They were more likely to undergo classic Whipple and to have a drain placed. After 3:1 matching, 1002 OPD patients were compared with 334 MIPD patients. MIPD was associated with longer mean operative time (426.6 vs 359.6 minutes; P < 0.01), higher readmission rate (19.2% vs 14.3%; P = 0.04) and lower rate of prolonged length of stay >14 days (16.5% vs 21.6%; P = 0.047). The 2 groups had a similar rate of 30-day mortality (MIPD 1.8% vs OPD 1.3%; P = 0.51), overall complications, postoperative pancreatic fistula, and delayed gastric emptying. A secondary analysis comparing MIPD without conversion or open assist with OPD showed that MIPD patients had lower rates of overall surgical site infection (13.4% vs 19.6%; P = 0.04) and transfusion (7.9% vs 14.4%; P = 0.02). CONCLUSIONS: MIPD had an equivalent morbidity and mortality rate to OPD, with the benefit of a decreased rate of prolonged length of stay, though this is partially offset by an increased readmission rate.


Asunto(s)
Laparoscopía , Pancreaticoduodenectomía/métodos , Procedimientos Quirúrgicos Robotizados , Adulto , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Humanos , Análisis de Intención de Tratar , Modelos Logísticos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Selección de Paciente , Puntaje de Propensión , Estudios Retrospectivos
13.
Breast Cancer Res Treat ; 161(3): 463-471, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28005245

RESUMEN

PURPOSE: The objective is to define the therapeutic role of antiplatelet agents in a triple-negative breast cancer (TNBC) population. METHODS: We performed retrospective analysis using the UTSW TNBC registry containing data from 222 Stage II-III TNBC patients treated between 1998 and 2016. Univariate analysis and multivariable logistic regression models were constructed to identify factors associated with disease-free survival (DFS), distant metastases rate (DMR), and overall survival outcomes. Antiplatelet drug use was determined by review of electronic medical records. RESULTS: A total of 65 patients used antiplatelet (AP) agents, and 157 patients did not use AP agents. Median follow-up for AP and non-AP groups was 41.3 and 40.9 months, respectively. There was an improvement in the AP group compared with the control group in 5-year DFS (80.4% at 5 years compared with 62.3% in the control group, p = 0.04) and 5-year DMR (8.8 vs. 31.9%, p = 0.007). In multivariate analysis, AP use was found to be significantly associated with improvements in DFS and DMR. CONCLUSIONS: We illustrate that antiplatelet agent use improves DMR and DFS among a stage II and III TNBC population despite our short follow-up evaluation. Longer follow-up evaluation will be required to determine additional outcome advantage for antiplatelet agent use. Our findings support consideration of investigation of antiplatelet therapy as an adjunctive therapy for TNBC at high risk for disease recurrence.


Asunto(s)
Aspirina/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Aspirina/administración & dosificación , Neoplasias de la Mama , Terapia Combinada , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Inhibidores de Agregación Plaquetaria/administración & dosificación , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/diagnóstico
14.
J Surg Oncol ; 116(1): 83-88, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28346693

RESUMEN

Novel, tumor-selective therapies are needed to increase the survival rate of pancreatic cancer patients. K-Ras-mutant-driven NAD(P)H:quinone oxidoreductase 1 (NQO1) is over-expressed in pancreatic tumor versus associated normal tissue, while catalase expression is lowered compared to levels in associated normal pancreas tissue. ARQ761 undergoes a robust, futile redox cycle in NQO1+ cancer cells, producing massive hydrogen peroxide (H2 O2 ) levels; normal tissues are spared by low NQO1 and high catalase expression. DNA damage created by ARQ761 in pancreatic cancer cells "hyperactivates" PARP1, causing metabolic catastrophe and NAD ± keresis cell death. NQO1: catalase levels (high in tumor, low in normal tissue) are an attractive therapeutic window to treat pancreatic cancer. Based on a growing body of literature, we are leading a clinical trial to evaluate the combination of ARQ761 and chemotherapy in patients with pancreatic cancer.


Asunto(s)
NAD(P)H Deshidrogenasa (Quinona)/antagonistas & inhibidores , Naftoquinonas/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Albúminas/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Ensayos Clínicos Fase I como Asunto , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Humanos , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Paclitaxel/farmacología , Neoplasias Pancreáticas/metabolismo , Gemcitabina
15.
Proc Natl Acad Sci U S A ; 111(46): 16538-43, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25359211

RESUMEN

Why different species are predisposed to different tumor spectra is not well understood. In particular, whether the physical location of tumor suppressor genes relative to one another influences tumor predisposition is unknown. Renal cancer presents a unique opportunity to explore this question. Renal cell carcinoma (RCC) of clear-cell type (ccRCC), the most common type, begins with an intragenic mutation in the von Hippel-Lindau (VHL) gene and loss of 3p (where VHL is located). Chromosome 3p harbors several additional tumor suppressor genes, including BRCA1-associated protein-1 (BAP1). In the mouse, Vhl is on a different chromosome than Bap1. Thus, whereas loss of 3p in humans simultaneously deletes one copy of BAP1, loss of heterozygosity in the corresponding Vhl region in the mouse would not affect Bap1. To test the role of BAP1 in ccRCC development, we generated mice deficient for either Vhl or Vhl together with one allele of Bap1 in nephron progenitor cells. Six2-Cre;Vhl(F/F);Bap1(F/+) mice developed ccRCC, but Six2-Cre;Vhl(F/F) mice did not. Kidneys from Six2-Cre;Vhl(F/F);Bap1(F/+) mice resembled kidneys from humans with VHL syndrome, containing multiple lesions spanning from benign cysts to cystic and solid RCC. Although the tumors were small, they showed nuclear atypia and exhibited features of human ccRCC. These results provide an explanation for why VHL heterozygous humans, but not mice, develop ccRCC. They also explain why a mouse model of ccRCC has been lacking. More broadly, our data suggest that differences in tumor predisposition across species may be explained, at least in part, by differences in the location of two-hit tumor suppressor genes across the genome.


Asunto(s)
Carcinoma de Células Renales/genética , Modelos Animales de Enfermedad , Genes Supresores de Tumor , Fallo Renal Crónico/genética , Neoplasias Renales/genética , Proteínas Supresoras de Tumor/fisiología , Ubiquitina Tiolesterasa/fisiología , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Edad de Inicio , Alelos , Animales , Linaje de la Célula , Mapeo Cromosómico , Femenino , Genes Reporteros , Genes Sintéticos , Predisposición Genética a la Enfermedad , Humanos , Enfermedades Renales Quísticas/genética , Enfermedades Renales Quísticas/patología , Fallo Renal Crónico/sangre , Fallo Renal Crónico/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Modelos Genéticos , Células Madre Multipotentes/metabolismo , Células Madre Multipotentes/patología , Mutación , Fenotipo , Lesiones Precancerosas/genética , Lesiones Precancerosas/patología , Especificidad de la Especie , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/antagonistas & inhibidores , Ubiquitina Tiolesterasa/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/antagonistas & inhibidores , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
16.
HPB (Oxford) ; 19(12): 1037-1045, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28867297

RESUMEN

BACKGROUND: Despite the development of pathways to enhance recovery and discharge to home, a significant proportion of patients are discharged to inpatient facilities after pancreaticoduodenectomy (PD). The aim of this study was to determine the rate of non-home discharge (NHD) following PD in a national cohort of patients and to develop predictive nomograms for NHD. METHODS: The National Surgical Quality Improvement Program was used to construct and validate pre- and postoperative nomograms for NHD following PD. RESULTS: A total of 6856 patients who underwent PD were identified, of which 927 (13.5%) had an NHD. The independent preoperative predictors of NHD were being female, older age, higher BMI, low serum albumin, >10% weight loss, ASA class III/IV, and being diagnosed with a bile duct/ampullary neoplasm or neuroendocrine tumor. A preoperative nomogram was constructed with a concordance index of 0.77. When postoperative variables were added to the model, the concordance index increased to 0.82. The postoperative predictors of NHD were return to the operating room, length of stay of ≥14 days, and any inpatient complications. CONCLUSIONS: These nomograms could be useful risk assessment tools to predict NHD after PD and therefore facilitate patient counseling and improve resource utilization and discharge planning.


Asunto(s)
Técnicas de Apoyo para la Decisión , Nomogramas , Pancreaticoduodenectomía/efectos adversos , Alta del Paciente , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Valor Predictivo de las Pruebas , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
17.
Pediatr Blood Cancer ; 63(10): 1753-60, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27199087

RESUMEN

BACKGROUND: Despite intensive therapy, children with metastatic and recurrent sarcoma or neuroblastoma have a poor prognosis. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is a noninvasive technique allowing the delivery of targeted ultrasound energy under MR imaging guidance. MR-HIFU may be used to ablate tumors without ionizing radiation or target chemotherapy using hyperthermia. Here, we evaluated the anatomic locations of tumors to assess the technical feasibility of MR-HIFU therapy for children with solid tumors. PROCEDURE: Patients with sarcoma or neuroblastoma with available cross-sectional imaging were studied. Tumors were classified based on the location and surrounding structures within the ultrasound beam path as (i) not targetable, (ii) completely or partially targetable with the currently available MR-HIFU system, and (iii) potentially targetable if a respiratory motion compensation technique was used. RESULTS: Of the 121 patients with sarcoma and 61 patients with neuroblastoma, 64% and 25% of primary tumors were targetable at diagnosis, respectively. Less than 20% of metastases at diagnosis or relapse were targetable for both sarcoma and neuroblastoma. Most targetable lesions were located in extremities or in the pelvis. Respiratory motion compensation may increase the percentage of targetable tumors by 4% for sarcomas and 10% for neuroblastoma. CONCLUSIONS: Many pediatric sarcomas are localized at diagnosis and are targetable by current MR-HIFU technology. Some children with neuroblastoma have bony tumors targetable by MR-HIFU at relapse, but few newly diagnosed children with neuroblastoma have tumors amenable to MR-HIFU therapy. Clinical trials of MR-HIFU should focus on patients with anatomically targetable tumors.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Imagen por Resonancia Magnética , Sarcoma/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Movimiento , Sarcoma/diagnóstico por imagen , Sarcoma/patología
18.
EMBO J ; 30(16): 3242-58, 2011 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-21804531

RESUMEN

Mammalian target of rapamycin (mTOR) complex 1 (mTORC1) is an important, highly conserved, regulator of cell growth. Ancient among the signals that regulate mTORC1 are nutrients. Amino acids direct mTORC1 to the surface of the late endosome/lysosome, where mTORC1 becomes receptive to other inputs. However, the interplay between endosomes and mTORC1 is poorly understood. Here, we report the discovery of a network that links mTORC1 to a critical component of the late endosome/lysosome, the V-ATPase. In an unbiased screen, we found that mTORC1 regulated the expression of, among other lysosomal genes, the V-ATPases. mTORC1 regulates V-ATPase expression both in cells and in mice. V-ATPase regulation by mTORC1 involves a transcription factor translocated in renal cancer, TFEB. TFEB is required for the expression of a large subset of mTORC1 responsive genes. mTORC1 coordinately regulates TFEB phosphorylation and nuclear localization and in a manner dependent on both TFEB and V-ATPases, mTORC1 promotes endocytosis. These data uncover a regulatory network linking an oncogenic transcription factor that is a master regulator of lysosomal biogenesis, TFEB, to mTORC1 and endocytosis.


Asunto(s)
Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/fisiología , Endocitosis/fisiología , Procesamiento Proteico-Postraduccional , Proteínas/fisiología , ATPasas de Translocación de Protón Vacuolares/fisiología , Secuencias de Aminoácidos , Animales , Línea Celular Transformada/efectos de los fármacos , Línea Celular Transformada/metabolismo , Dactinomicina/farmacología , Endocitosis/efectos de los fármacos , Inducción Enzimática/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Lisosomas/enzimología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Complejos Multiproteicos , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/fisiología , Transducción de Señal/fisiología , Sirolimus/farmacología , Serina-Treonina Quinasas TOR , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor/fisiología , ATPasas de Translocación de Protón Vacuolares/biosíntesis , ATPasas de Translocación de Protón Vacuolares/genética
19.
Oncologist ; 20(6): 674-82, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26018661

RESUMEN

BACKGROUND: Lack of access to available cancer clinical trials has been cited as a key factor limiting trial accrual, particularly among medically underserved populations. We examined the trends and factors in clinical trial availability within a major U.S. safety-net hospital system. MATERIALS AND METHODS: We identified cancer clinical trials activated at the Harold C. Simmons Cancer from 1991 to 2014 and recorded the characteristics of the trials that were and were not activated at the Parkland Health and Hospital System satellite site. We used univariate and multivariate logistic regression to determine the association between trial characteristics and nonactivation status, and chi-square analysis to determine the association between the trial characteristics and the reasons for nonactivation. RESULTS: A total of 773 trials were identified, of which 152 (20%) were not activated at Parkland. In multivariable analysis, nonactivation at Parkland was associated with trial year, sponsor, and phase. Compared with the 1991-2006 period, clinical trials in the 2007-2014 period were almost eightfold more likely not to be activated at Parkland. The most common reasons for nonactivation at Parkland were an inability to perform the study procedures (27%) and the startup costs (15%). CONCLUSION: Over time, in this single-center setting, a decreasing proportion of cancer clinical trials were available to underserved populations. Trial complexity and costs appeared to account for much of this trend. Efforts to overcome these barriers will be key to equitable access to clinical trials, efficient accrual, and the generalizability of the results. IMPLICATIONS FOR PRACTICE: Despite numerous calls to increase and diversify cancer clinical trial accrual, the present study found that cancer clinical trial activation rates in a safety-net setting for medically underserved populations have decreased substantially in recent years. The principal reasons for study nonactivation were expenses and an inability to perform the study-related procedures, reflecting the increasing costs and complexity of cancer clinical trials. Future efforts need to focus on strategies to mitigate the increasing disparity in access to clinical research and cutting-edge therapies, which also threatens to hinder study accrual, completion rates, and generalizability.


Asunto(s)
Ensayos Clínicos como Asunto , Neoplasias/epidemiología , Poblaciones Vulnerables , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Estados Unidos
20.
J Natl Compr Canc Netw ; 13(4): 409-16, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25870377

RESUMEN

PURPOSE: The NCI requirement that clinical trials at NCI-designated cancer centers undergo scientific review in addition to Institutional Review Board review is unique among medical specialties. We evaluated the impact of this process on protocol development and content. METHODS: We analyzed cancer clinical trials that underwent full board review by the Harold C. Simmons Cancer Center Protocol Review and Monitoring Committee (PRMC) from January 1, 2009, through June 30, 2013. We analyzed associations between trial characteristics, PRMC decisions, and protocol modifications using Chi-square testing, Fishers exact testing, and logistic regression. RESULTS: A total of 226 trials were analyzed. Of these, 77% were industry-sponsored and 23% were investigator-initiated. Initial PRMC decisions were: approval (40%), provisional approval (52%), deferral (7%), and disapproval (1%). These decisions were associated with study sponsor (P<.001) and phase (P<.001). Ultimately, 97% of industry-sponsored and 90% of investigator-initiated trials were approved (P=.05). Changes were requested for 27% of industry-sponsored trials compared with 54% of investigator-initiated trials (P<.001). Total changes requested (mean, 5.6 vs 2.4; P<.001) and implemented (mean, 4.6 vs 2.1; P=.008) per protocol were significantly greater for investigator-initiated trials. Changes related to study design were more commonly requested (35% vs 13% of trials) and implemented (40% vs 5% of trials) for investigator-initiated trials compared with industry-sponsored trials (P=.03). CONCLUSIONS: NCI-mandated scientific protocol review seems to have a substantial impact on investigator-initiated trials but less effect on industry-sponsored trials. These findings may provide guidance on development and prioritization of institutional protocol review policies.


Asunto(s)
Comités Consultivos , Investigación Biomédica/normas , Protocolos Clínicos/normas , Ensayos Clínicos como Asunto/normas , Neoplasias/terapia , Investigación Biomédica/economía , Ensayos Clínicos como Asunto/economía , Ensayos Clínicos como Asunto/estadística & datos numéricos , Regulación Gubernamental , Humanos , Industrias/economía , National Cancer Institute (U.S.)/legislación & jurisprudencia , Proyectos de Investigación/normas , Apoyo a la Investigación como Asunto , Estados Unidos
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