Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Nucleic Acids Res ; 47(22): 11623-11636, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31647098

RESUMO

Alternative splicing is emerging as an oncogenic mechanism. In prostate cancer, generation of constitutively active forms of androgen receptor (AR) variants including AR-V7 plays an important role in progression of castration-resistant prostate cancer (CRPC). AR-V7 is generated by alternative splicing that results in inclusion of cryptic exon CE3 and translation of truncated AR protein that lacks the ligand binding domain. Whether AR-V7 can be a driver for CRPC remains controversial as the oncogenic mechanism of AR-V7 activation remains elusive. Here, we found that KDM4B promotes AR-V7 and identified a novel regulatory mechanism. KDM4B is phosphorylated by protein kinase A under conditions that promote castration-resistance, eliciting its binding to the splicing factor SF3B3. KDM4B binds RNA specifically near the 5'-CE3, upregulates the chromatin accessibility, and couples the spliceosome to the chromatin. Our data suggest that KDM4B can function as a signal responsive trans-acting splicing factor and scaffold that recruits and stabilizes the spliceosome near the alternative exon, thus promoting its inclusion. Genome-wide profiling of KDM4B-regulated genes also identified additional alternative splicing events implicated in tumorigenesis. Our study defines KDM4B-regulated alternative splicing as a pivotal mechanism for generating AR-V7 and a contributing factor for CRPC, providing insight for mechanistic targeting of CRPC.


Assuntos
Processamento Alternativo/genética , Regulação Neoplásica da Expressão Gênica/genética , Histona Desmetilases com o Domínio Jumonji/genética , Neoplasias de Próstata Resistentes à Castração/genética , Receptores Androgênicos/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Cromatina/metabolismo , Células HEK293 , Humanos , Masculino , Isoformas de Proteínas/genética , Receptores Androgênicos/metabolismo , Spliceossomos/genética
2.
Crit Care Med ; 45(1): 28-34, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27513533

RESUMO

OBJECTIVE: Recent studies reveal a high occurrence of overdiagnosis of heparin-induced thrombocytopenia in surgical patients with critical illness. The optimal criteria for diagnosis of heparin-induced thrombocytopenia remain unclear, contributing to unnecessary treatment. We reviewed patients who were admitted to surgical ICUs and were suspected of heparin-induced thrombocytopenia to identify how often patients were correctly treated. DESIGN: In this clinical prospective study, data were collected including age, sex, antiplatelet factor 4/heparin enzyme-linked immunosorbent assay, serotonin release assay, and Warkentin 4Ts scores. Heparin-induced thrombocytopenia-positive patients were defined as those with both positive antiplatelet factor 4/heparin enzyme-linked immunosorbent assay (optical density, ≥ 0.40) and positive serotonin release assay results. SETTING: Urban tertiary medical center. PATIENTS: Patients admitted to the surgical and cardiac ICU who were presumed to have heparin-induced thrombocytopenia and underwent antiplatelet factor 4/heparin enzyme-linked immunosorbent assay and serotonin release assay testing between January 1, 2011, and August 1, 2014. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 135 patients had 4Ts, antiplatelet factor 4/heparin enzyme-linked immunosorbent assay, and serotonin release assay scores. A total of 11 patients (8.1%) had positive serotonin release assay and 80 patients had positive antiplatelet factor 4/heparin enzyme-linked immunosorbent assay; 10 patients were identified as heparin-induced thrombocytopenia positive. Positive serotonin release assay was noted in nine of 11 patients (81.8%) with antiplatelet factor 4/heparin enzyme-linked immunosorbent assay optical density greater than or equal to 2.0, compared with one of 22 patients (4.5%) with optical density values of 0.85-1.99, and one of 102 patients (1.0%) with optical density values of 0-0.84. Out of 135 patients, 29 patients (21.5%) received treatment with argatroban, lepirudin, or fondaparinux: 10 of 10 heparin-induced thrombocytopenia-positive patients (100%) compared with 19 of 125 heparin-induced thrombocytopenia-negative patients (15%). CONCLUSIONS: Overtreatment of heparin-induced thrombocytopenia in the surgical ICU continues even with recent increased caution encouraging a higher antiplatelet factor 4/heparin enzyme-linked immunosorbent assay optical density threshold before initiating treatment. More stringent criteria should be used to determine when to order serologic testing and when the results of such testing should prompt a change in anticoagulant treatment. If antiplatelet factor 4/heparin enzyme-linked immunosorbent assay is used to consider immediate treatment, an optical density greater than or equal to 2.0 may be a more appropriate threshold.


Assuntos
Anticoagulantes/efeitos adversos , Heparina/efeitos adversos , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Trombocitopenia/induzido quimicamente , Trombocitopenia/tratamento farmacológico , Centros Médicos Acadêmicos , Idoso , Anticorpos/análise , Antitrombinas/uso terapêutico , Arginina/análogos & derivados , Ensaio de Imunoadsorção Enzimática , Feminino , Fondaparinux , Hirudinas , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Ácidos Pipecólicos/uso terapêutico , Fator Plaquetário 4/imunologia , Polissacarídeos/uso terapêutico , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Serotonina/metabolismo , Sulfonamidas
3.
Am J Pathol ; 185(9): 2505-22, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26362718

RESUMO

Active Stat5a/b predicts early recurrence and disease-specific death in prostate cancer (PC), which both typically are caused by development of metastatic disease. Herein, we demonstrate that Stat5a/b induces epithelial-to-mesenchymal transition (EMT) of PC cells, as shown by Stat5a/b regulation of EMT marker expression (Twist1, E-cadherin, N-cadherin, vimentin, and fibronectin) in PC cell lines, xenograft tumors in vivo, and patient-derived PCs ex vivo using organ explant cultures. Jak2-Stat5a/b signaling induced functional end points of EMT as well, indicated by disruption of epithelial cell monolayers and increased migration and adhesion of PC cells to fibronectin. Knockdown of Twist1 suppressed Jak2-Stat5a/b-induced EMT properties of PC cells, which were rescued by re-introduction of Twist1, indicating that Twist1 mediates Stat5a/b-induced EMT in PC cells. While promoting EMT, Jak2-Stat5a/b signaling induced stem-like properties in PC cells, such as sphere formation and expression of cancer stem cell markers, including BMI1. Mechanistically, both Twist1 and BMI1 were critical for Stat5a/b induction of stem-like features, because genetic knockdown of Twist1 suppressed Stat5a/b-induced BMI1 expression and sphere formation in stem cell culture conditions, which were rescued by re-introduction of BMI1. By using human prolactin knock-in mice, we demonstrate that prolactin-Stat5a/b signaling promoted metastases formation of PC cells in vivo. In conclusion, our data support the concept that Jak2-Stat5a/b signaling promotes metastatic progression of PC by inducing EMT and stem cell properties in PC cells.


Assuntos
Transição Epitelial-Mesenquimal , Janus Quinase 2/metabolismo , Neoplasias da Próstata/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Animais , Caderinas/metabolismo , Humanos , Masculino , Camundongos , Células-Tronco Neoplásicas/patologia , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/patologia , Recidiva , Transdução de Sinais/fisiologia , Proteína 1 Relacionada a Twist/metabolismo
4.
J Surg Res ; 202(2): 455-60, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-27041599

RESUMO

BACKGROUND: Changes in health care policies have influenced transformations in hospital systems to be cost-efficient while maintaining robust outcomes. This is particularly important in intensive care units where significant resources are used to care for critically ill patients. We sought to determine whether high-value care processes (HVCp) implemented in a surgical intensive care unit (SICU) have an impact on commonly used ancillary tests. MATERIALS AND METHODS: An implementation phase using a Lean Six Sigma approach was performed in October 2014 at a 24-bed large academic center SICU with aims to decrease orders of excessive daily laboratory tests and X-rays. The HVCp implemented included use of daily checklists, staff education, and visual reminders emphasizing the importance of appropriate laboratory tests and chest X-rays. Preintervention (July 2014-October 2014) and post-intervention (November 2014-June 2015) phases were compared. RESULTS: Average SICU census, case mix index (4.3 versus 4.4, P = 0.57), all patient refined severity of illness (3.2 versus 3.2, P = 0.91), and SICU mortality (7.1% versus 5.1%, P = 0.18) were similar in both phases. A significant reduction of excessive laboratory tests was evident after the implementation period. Eight hundred sixty-five arterial blood gases/mo were obtained in the preintervention phase compared with 420 arterial blood gases/mo after intervention (P = 0.004), representing a 51.4% reduction. Similar results were obtained with complete blood counts, basic metabolic profiles, coagulation profiles, and chest X-rays (12%, 17.8%, 30.2%, and 20.3% reductions, respectively), a total estimated cost savings of $59,137/mo and prevention of excess phlebotomy of approximately 4 L of blood/mo. CONCLUSIONS: By implementing an HVCp including a checklist, visual reminders, and provider education, we significantly reduced the use of commonly ordered ancillary tests in the SICU without affecting outcomes, resulting in an annual cost savings of $710,000.


Assuntos
Cuidados Críticos/organização & administração , Unidades de Terapia Intensiva/organização & administração , Melhoria de Qualidade/organização & administração , Procedimentos Desnecessários/estatística & dados numéricos , California , Lista de Checagem , Controle de Custos , Cuidados Críticos/economia , Cuidados Críticos/métodos , Educação Médica Continuada , Educação Continuada em Enfermagem , Custos Hospitalares/estatística & dados numéricos , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva/economia , Internato e Residência , Avaliação de Processos e Resultados em Cuidados de Saúde , Melhoria de Qualidade/economia , Estudos Retrospectivos , Procedimentos Desnecessários/economia
5.
J Surg Res ; 200(1): 221-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26188959

RESUMO

BACKGROUND: Although beta-adrenergic receptor blockade may improve outcomes after traumatic brain injury (TBI), its early use is not routine. We hypothesize that judicious early low-dose propranolol after TBI (EPAT) will improve outcomes without altering bradycardia or hypotensive events. METHODS: We conducted a prospective, observational study on all patients who presented with moderate-to-severe TBI from March 2010-August 2013. Ten initial patients did not receive propranolol (control). Subsequent patients received propranolol at 1-mg intravenous every 6 h starting within 12 h of intensive care unit (ICU) admission (EPAT) for a minimum of 48 h. Heart rate and blood pressure were recorded hourly for the first 72 h. Bradycardia and hypotensive events, mortality, and length of stay (LOS) were compared between cohorts to determine significant differences. RESULTS: Thirty-eight patients were enrolled; 10 control and 28 EPAT. The two cohorts were similar when compared by gender, emergency department (ED) systolic blood pressure, ED heart rate, and mortality. ED Glasgow coma scale was lower (4.2 versus 10.7, P < 0.01) and injury severity score higher in control. EPAT patients received a mean of 10 ± 14 doses of propranolol. Hypotensive events were similar between cohorts, whereas bradycardia events were higher in control (5.8 versus 1.6, P = 0.05). ICU LOS (15.4 versus 30.4 d, P = 0.02) and hospital LOS (10 versus 19.1 d, P = 0.05) were lower in EPAT. Mortality rates were similar between groups (10% versus 10.7%, P = 0.9). The administration of propranolol led to no recorded complications. CONCLUSIONS: Although bradycardia and hypotensive events occur early after TBI, low-dose intravenous propranolol does not increase their number or severity. Early use of propranolol after TBI appears to be safe and may be associated with decreased ICU and hospital LOS.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Lesões Encefálicas/tratamento farmacológico , Propranolol/uso terapêutico , Adulto , Idoso , Bradicardia/induzido quimicamente , Lesões Encefálicas/complicações , Esquema de Medicação , Feminino , Humanos , Hipotensão/induzido quimicamente , Injeções Intravenosas , Escala de Gravidade do Ferimento , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
6.
Am J Pathol ; 182(6): 2264-75, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23660011

RESUMO

The molecular mechanisms underlying progression of prostate cancer (PCa) to castrate-resistant (CR) and metastatic disease are poorly understood. Our previous mechanistic work shows that inhibition of transcription factor Stat5 by multiple alternative methods induces extensive rapid apoptotic death of Stat5-positive PCa cells in vitro and inhibits PCa xenograft tumor growth in nude mice. Furthermore, STAT5A/B induces invasive behavior of PCa cells in vitro and in vivo, suggesting involvement of STAT5A/B in PCa progression. Nuclear STAT5A/B protein levels are increased in high-grade PCas, CR PCas, and distant metastases, and high nuclear STAT5A/B expression predicts early disease recurrence and PCa-specific death in clinical PCas. Based on these findings, STAT5A/B represents a therapeutic target protein for advanced PCa. The mechanisms underlying increased Stat5 protein levels in PCa are unclear. Herein, we demonstrate amplification at the STAT5A/B gene locus in a significant fraction of clinical PCa specimens. STAT5A/B gene amplification was more frequently found in PCas of high histologic grades and in CR distant metastases. Quantitative in situ analysis revealed that STAT5A/B gene amplification was associated with increased STAT5A/B protein expression in PCa. Functional studies showed that increased STAT5A/B copy numbers conferred growth advantage in PCa cells in vitro and as xenograft tumors in vivo. The work presented herein provides the first evidence of somatic STAT5A/B gene amplification in clinical PCas.


Assuntos
Amplificação de Genes , Neoplasias da Próstata/genética , Fator de Transcrição STAT5/genética , Proteínas Supressoras de Tumor/genética , Animais , Variações do Número de Cópias de DNA , DNA de Neoplasias/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Nus , Gradação de Tumores , Transplante de Neoplasias , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Recidiva , Fator de Transcrição STAT5/biossíntese , Transplante Heterólogo , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/biossíntese
7.
Biomed Opt Express ; 14(11): 5764-5780, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38021123

RESUMO

Triple negative breast cancer (TNBC) is a highly aggressive form of cancer. Detecting TNBC early is crucial for improving disease prognosis and optimizing treatment. Unfortunately, conventional imaging techniques fall short in providing a comprehensive differentiation of TNBC subtypes due to their limited sensitivity and inability to capture subcellular details. In this study, we present a multimodal imaging platform that integrates heavy water (D2O)-probed stimulated Raman scattering (DO-SRS), two-photon fluorescence (TPF), and second harmonic generation (SHG) imaging. This platform allows us to directly visualize and quantify the metabolic activities of TNBC subtypes at a subcellular level. By utilizing DO-SRS imaging, we were able to identify distinct levels of de novo lipogenesis, protein synthesis, cytochrome c metabolic heterogeneity, and lipid unsaturation rates in various TNBC subtype tissues. Simultaneously, TPF imaging provided spatial distribution mapping of NAD[P]H and flavin signals in TNBC tissues, revealing a high redox ratio and significant lipid turnover rate in TNBC BL2 (HCC1806) samples. Furthermore, SHG imaging enabled us to observe diverse orientations of collagen fibers in TNBC tissues, with higher anisotropy at the tissue boundary compared to the center. Our multimodal imaging platform offers a highly sensitive and subcellular approach to characterizing not only TNBC, but also other tissue subtypes and cancers.

8.
J Phys Chem Lett ; 14(18): 4313-4321, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37130045

RESUMO

The level of interest in probing the strength of noncovalent interactions in DNA duplexes is high, as these weak forces dictate the range of suprastructures the double helix adopts under different conditions, in turn directly impacting the biological functions and industrial applications of duplexes that require making and breaking them to access the genetic code. However, few experimental tools can measure these weak forces embedded within large biological suprastructures in the native solution environment. Here, we develop experimental methods for detecting the presence of a single noncovalent interaction [a hydrogen bond (H-bond)] within a large DNA duplex in solution and measure its formation enthalpy (ΔHf). We report that introduction of a H-bond into the TC2═O group from the noncanonical nucleobase 2-aminopurine produces an expected decrease ∼10 ± 0.76 cm-1 (from ∼1720 cm-1 in Watson-Crick to ∼1710 cm-1 in 2-aminopurine), which correlates with an enthalpy of ∼0.93 ± 0.066 kcal/mol for this interaction.


Assuntos
2-Aminopurina , DNA , Temperatura , Conformação de Ácido Nucleico , Ligação de Hidrogênio , Termodinâmica , DNA/química , Análise Espectral
9.
Chem Sci ; 14(44): 12645-12652, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38020363

RESUMO

A unique prospect of using halides as charge carriers is the possibility of the halides undergoing anodic redox behaviors when serving as charge carriers for the charge-neutrality compensation of electrodes. However, the anodic conversion of halides to neutral halogen species has often been irreversible at room temperature due to the emergence of diatomic halogen gaseous products. Here, we report that chloride ions can be reversibly converted to near-neutral atomic chlorine species in the Mn3O4 electrode at room temperature in a highly concentrated chloride-based aqueous electrolyte. Notably, the Zn2+ cations inserted in the first discharge and trapped in the Mn3O4 structure create an environment to stabilize the converted chlorine atoms within the structure. Characterization results suggest that the Cl/Cl- redox is responsible for the observed large capacity, as the oxidation state of Mn barely changes upon charging. Computation results corroborate that the converted chlorine species exist as polychloride monoanions, e.g., [Cl3]- and [Cl5]-, inside the Zn2+-trapped Mn3O4, and the presence of polychloride species is confirmed experimentally. Our results point to the halogen plating inside electrode lattices as a new charge-storage mechanism.

10.
Mol Cancer Ther ; 19(1): 231-246, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31548294

RESUMO

The second-generation antiandrogen, enzalutamide, is approved for castrate-resistant prostate cancer (CRPC) and targets androgen receptor (AR) activity in CRPC. Despite initial clinical activity, acquired resistance to enzalutamide arises rapidly and most patients develop terminal disease. Previous work has established Stat5 as a potent inducer of prostate cancer growth. Here, we investigated the significance of Jak2-Stat5 signaling in resistance of prostate cancer to enzalutamide. The levels of Jak2 and Stat5 mRNA, proteins and activation were evaluated in prostate cancer cells, xenograft tumors, and clinical prostate cancers before and after enzalutamide therapy. Jak2 and Stat5 were suppressed by genetic knockdown using lentiviral shRNA or pharmacologic inhibitors. Responsiveness of primary and enzalutamide-resistant prostate cancer to pharmacologic inhibitors of Jak2-Stat5 signaling was assessed in vivo in mice bearing prostate cancer xenograft tumors. Patient-derived prostate cancers were tested for responsiveness to Stat5 blockade as second-line treatment after enzalutamide ex vivo in tumor explant cultures. Enzalutamide-liganded AR induces sustained Jak2-Stat5 phosphorylation in prostate cancer leading to the formation of a positive feed-forward loop, where activated Stat5, in turn, induces Jak2 mRNA and protein levels contributing to further Jak2 activation. Mechanistically, enzalutamide-liganded AR induced Jak2 phosphorylation through a process involving Jak2-specific phosphatases. Stat5 promoted prostate cancer growth during enzalutamide treatment. Jak2-Stat5 inhibition induced death of prostate cancer cells and patient-derived prostate cancers surviving enzalutamide treatment and blocked enzalutamide-resistant tumor growth in mice. This work introduces a novel concept of a pivotal role of hyperactivated Jak2-Stat5 signaling in enzalutamide-resistant prostate cancer, which is readily targetable by Jak2 inhibitors in clinical development.


Assuntos
Janus Quinase 2/antagonistas & inibidores , Feniltioidantoína/análogos & derivados , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Animais , Benzamidas , Humanos , Masculino , Camundongos , Camundongos Nus , Nitrilas , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/patologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Clin Cancer Res ; 24(8): 1917-1931, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29483142

RESUMO

Purpose: The standard treatment for organ-confined prostate cancer is surgery or radiation, and locally advanced prostate cancer is typically treated with radiotherapy alone or in combination with androgen deprivation therapy. Here, we investigated whether Stat5a/b participates in regulation of double-strand DNA break repair in prostate cancer, and whether Stat5 inhibition may provide a novel strategy to sensitize prostate cancer to radiotherapy.Experimental Design: Stat5a/b regulation of DNA repair in prostate cancer was evaluated by comet and clonogenic survival assays, followed by assays specific to homologous recombination (HR) DNA repair and nonhomologous end joining (NHEJ) DNA repair. For HR DNA repair, Stat5a/b regulation of Rad51 and the mechanisms underlying the regulation were investigated in prostate cancer cells, xenograft tumors, and patient-derived prostate cancers ex vivo in 3D explant cultures. Stat5a/b induction of Rad51 and HR DNA repair and responsiveness to radiation were evaluated in vivo in mice bearing prostate cancer xenograft tumors.Results: Stat5a/b is critical for Rad51 expression in prostate cancer via Jak2-dependent mechanisms by inducing Rad51 mRNA levels. Consistent with this, genetic knockdown of Stat5a/b suppressed HR DNA repair while not affecting NHEJ DNA repair. Pharmacologic Stat5a/b inhibition potently sensitized prostate cancer cell lines and prostate cancer tumors to radiation, while not inducing radiation sensitivity in the neighboring tissues.Conclusions: This work introduces a novel concept of a pivotal role of Jak2-Stat5a/b signaling for Rad51 expression and HR DNA repair in prostate cancer. Inhibition of Jak2-Stat5a/b signaling sensitizes prostate cancer to radiation and, therefore, may provide an adjuvant therapy for radiation to reduce radiation-induced damage to the neighboring tissues. Clin Cancer Res; 24(8); 1917-31. ©2018 AACR.


Assuntos
Reparo do DNA , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Rad51 Recombinase/metabolismo , Tolerância a Radiação/genética , Fator de Transcrição STAT5/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Modelos Animais de Doenças , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , RNA Interferente Pequeno/genética , Rad51 Recombinase/genética , Tolerância a Radiação/efeitos dos fármacos , Radiação Ionizante , Fator de Transcrição STAT5/antagonistas & inibidores , Fator de Transcrição STAT5/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Oncotarget ; 8(2): 3724-3745, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27741508

RESUMO

Despite aggressive treatment for localized cancer, prostate cancer (PC) remains a leading cause of cancer-related death for American men due to a subset of patients progressing to lethal and incurable metastatic castrate-resistant prostate cancer (CRPC). Organ-confined PC is treated by surgery or radiation with or without androgen deprivation therapy (ADT), while options for locally advanced and disseminated PC include radiation combined with ADT, or systemic treatments including chemotherapy. Progression to CRPC results from failure of ADT, which targets the androgen receptor (AR) signaling axis and inhibits AR-driven proliferation and survival pathways. The exact mechanisms underlying the transition from androgen-dependent PC to CRPC remain incompletely understood. Reactivation of AR has been shown to occur in CRPC despite depletion of circulating androgens by ADT. At the same time, the presence of AR-negative cell populations in CRPC has also been identified. While AR signaling has been proposed as the primary driver of CRPC, AR-independent signaling pathways may represent additional mechanisms underlying CRPC progression. Identification of new therapeutic strategies to target both AR-positive and AR-negative PC cell populations and, thereby, AR-driven as well as non-AR-driven PC cell growth and survival mechanisms would provide a two-pronged approach to eliminate CRPC cells with potential for synthetic lethality. In this review, we provide an overview of AR-dependent and AR-independent molecular mechanisms which drive CRPC, with special emphasis on the role of the Jak2-Stat5a/b signaling pathway in promoting castrate-resistant growth of PC through both AR-dependent and AR-independent mechanisms.


Assuntos
Neoplasias da Próstata/etiologia , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Transformação Celular Neoplásica/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Janus Quinase 2/metabolismo , Ligantes , Masculino , Terapia de Alvo Molecular , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/etiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
J Trauma Acute Care Surg ; 80(3): 398-403; discussion 403-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26906645

RESUMO

BACKGROUND: The obese state has been linked to several immune-mediated conditions. Our objective was to examine the association of body mass index (BMI) with the diagnosis of heparin-induced thrombocytopenia (HIT). METHODS: Prospectively collected data on patients in the surgical and cardiac intensive care unit suspected of having HIT between January 2007 and August 2014 were analyzed. Patients were categorized into five discrete BMI (kg/m) groups and compared. Data collected included Warkentin 4-T scores, antiplatelet factor 4 (anti-PF4OD) values, serotonin release assay values, and thromboembolic diseases. HIT positivity was defined as serotonin release assay value greater than 20%. RESULTS: Of 304 patients meeting inclusion criteria, mean (SD) age was 62.1 (16.5) years, 59% were male, and mean (SD) BMI was 27 (6) kg/m. Thirty-six (12%) were positive for HIT. Incidence of HIT increased progressively with BMI (0%, 8%, 11%, 19%, 36%; p < 0.001). Compared with patients with normal BMI, patients with a BMI of 30 kg/m to 39.9 kg/m had a 200% increase in the odds for HIT (odds ratio [OR], 2.94; 95% confidence interval [CI], 1.20-7.54; p = 0.019), while patients with a BMI of 40 kg/m or greater had a 600% increase (OR, 6.98; 95% CI, 1.59-28.2; p = 0.012). After regression analysis, BMI remained an independent predictor of the development of HIT (adjusted OR per kg/m, 1.08; 95% CI, 1.02-1.14; p = 0.010). Anti-PF4OD values greater than or equal to 2.0 also increased with BMI (p < 0.001). In-hospital mortality increased significantly with BMI above normal (p = 0.026). Warkentin 4-T scores, deep venous thrombosis, pulmonary embolism, and stroke incidence did not correlate with changes in BMI. CONCLUSION: Increasing BMI seems to be strongly associated with increased rates of HIT in intensive care unit patients. Obesity is an important new clinical variable for estimating the pretest probability of HIT, and patient "thickness" could be considered a fifth "T" of the 4-T scoring system. Additional biochemical work is indicated to decipher the role of obesity in this immune-mediated condition. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III.


Assuntos
Biomarcadores/sangue , Índice de Massa Corporal , Heparina/efeitos adversos , Unidades de Terapia Intensiva/estatística & dados numéricos , Trombocitopenia/diagnóstico , Anticorpos Anti-Idiotípicos/sangue , Anticorpos Anti-Idiotípicos/imunologia , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Heparina/uso terapêutico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fator Plaquetário 4/sangue , Fator Plaquetário 4/imunologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Prognóstico , Estudos Retrospectivos , Serotonina/sangue , Procedimentos Cirúrgicos Operatórios , Taxa de Sobrevida/tendências , Trombocitopenia/induzido quimicamente , Trombocitopenia/epidemiologia , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Estados Unidos/epidemiologia
14.
Am Surg ; 82(1): 41-5, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26802856

RESUMO

Blunt aortic injury (BAI) after chest trauma is a potentially lethal condition. Rapid diagnosis is important to appropriately treat patients. The purpose of this study was to compare CT with intravenous contrast (CTI) to CT with angiography (CTA) in the initial evaluation of blunt chest trauma patients. This was a retrospective review of all blunt trauma patients who received a CTI or CTA during the initial evaluation at an urban Level I trauma center from January 1, 2010 to December 31, 2013. Two-hundred and eighty-one trauma patients met inclusion criteria. Most, 167/281 (59%) received CTI and 114/281 (41%) received CTA. There were no differences between cohorts in age, gender, initial heart rate, systolic blood pressure, and Glasgow Coma Scale in emergency department. Mortality rates were similar for CTI and CTA (4% vs 8%, P = 0.20). CTI identified an injury in 54 per cent compared with 46 per cent in CTA (P = 0.05). Overall, 2 per cent of patients had BAI with similar rates in CTI and CTA (2% vs 2%, P = 0.80). BAI was not missed using either CTI or CTA. Trauma patients studied with CTI had similar diagnostic findings as CTA. CTI may be preferable to CTA during the initial assessment for possible BAI because of a single contrast injection for whole body CT.


Assuntos
Angiografia/métodos , Meios de Contraste , Traumatismos Torácicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ferimentos não Penetrantes/diagnóstico por imagem , Adulto , California , Estudos de Coortes , Feminino , Escala de Coma de Glasgow , Humanos , Infusões Intravenosas , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Sensibilidade e Especificidade , Traumatismos Torácicos/fisiopatologia , Fatores de Tempo , Centros de Traumatologia , População Urbana , Ferimentos não Penetrantes/fisiopatologia , Adulto Jovem
15.
Am Surg ; 81(10): 945-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26463286

RESUMO

Massive transfusion protocol (MTP) is used to resuscitate patients in hemorrhagic shock. Our goal was to review MTP use in the elderly. All trauma patients who required activation of MTP at an urban Level I trauma center from January 1, 2011 to December 31, 2013 were reviewed retrospectively. Elderly was defined as age ≥ 60 years. Sixty-six patients had MTP activated: 52 nonelderly (NE) and 14 elderly (E). There were no statistically significant differences between the two cohorts for gender, injury severity score, head abbreviated injury scale, emergency department Glasgow Coma Scale, initial hematocrit, intensive care unit length of stay, or hospital length of stay. Mean age for NE was 35 years and 73 years for E (P < 0.01). Less than half (43%) of E patients with activation of MTP received 10 or more units of blood products compared with 69 per cent of the NE (P = 0.07). Mortality rates were similar in the NE and the E (53%vs 50%, P = 0.80). After multivariate analysis with Glasgow Coma Scale, injury severity score, and blunt versus penetrating trauma, elderly age was not a predictor of mortality after MTP (P = 0.35). When MTP is activated, survival to discharge in elderly trauma patients is comparable to younger patients.


Assuntos
Transfusão de Sangue/métodos , Unidades de Terapia Intensiva , Choque Hemorrágico/terapia , Centros de Traumatologia , Ferimentos e Lesões/terapia , Adulto , Idoso , California , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Escala de Gravidade do Ferimento , Tempo de Internação/tendências , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Choque Hemorrágico/diagnóstico , Choque Hemorrágico/mortalidade , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/mortalidade
16.
Am Surg ; 81(10): 950-4, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26463287

RESUMO

Pain associated with rib fractures impairs respiratory function and increases pulmonary morbidity. The purpose of this study was to determine how epidural catheters alter mortality and complications in trauma patients. We performed a retrospective study involving adult blunt trauma patients with moderate-to-severe injuries from January 1, 2004 to December 31, 2013. During the 10-year period, 526 patients met the inclusion criteria; 43/526 (8%) patients had a catheter placed. Mean age of patients with epidural catheter (CATH) was higher compared with patients without epidural catheter (NOCATH) (54 vs 48 years, P = 0.021), Injury Severity Score was similar (26 CATH vs 27 NOCATH, P = 0.84), and CATH had higher mean rib fractures (7.4 vs 4.1, P < 0.001). Mortality was lower in CATH (0% vs 13%, P = 0.006). Deep vein thrombosis (DVT) rate was higher in CATH (12% vs. 5%, P = 0.036). After regression analysis, we found catheter placement to be a predictor for DVT (adjusted odds ratios 2.80, P = 0.036). Our center noted increased use of epidural catheters in patients who present with moderate-to-severe injuries. Patients with catheters were older and had a mean of 7.4 ribs fractured. The epidural cohort had longer hospital LOS and decreased mortality. In contrast to other studies, DVT rates were increased in patients who received epidural catheters.


Assuntos
Analgesia Epidural/métodos , Traumatismo Múltiplo , Manejo da Dor/métodos , Fraturas das Costelas/terapia , Ferimentos não Penetrantes/terapia , Adulto , Feminino , Seguimentos , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas das Costelas/diagnóstico , Fraturas das Costelas/etiologia , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/diagnóstico
17.
Am Surg ; 81(10): 1034-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26463303

RESUMO

Stab wounds (SW) to the abdomen traditionally require urgent exploration when associated with shock, evisceration, or peritonitis. Hemodynamically stable patients without evisceration may benefit from serial exams even with peritonitis. We compared patients taken directly to the operating room with abdominal SWs (ED-OR) to those admitted for serial exams (ADMIT). We retrospectively reviewed hemodynamically stable patients presenting with any abdominal SW between January 2000 and December 2012. Exclusions included evidence of evisceration, systolic blood pressure ≤110 mm Hg, or blood transfusion. NON-THER was defined as abdominal exploration without identification of intra-abdominal injury requiring repair. Of 142 patients included, 104 were ED-OR and 38 were ADMIT. When ED-OR was compared with ADMIT, abdominal Abbreviated Injury Score was higher (2.4 vs 2.1; P = 0.01) and hospital length of stay was longer (4.8 vs 3.3 days; P = 0.04). Incidence of NON-THER was higher in ED-OR cohort (71% vs 13%; P ≤ 0.001). In a regression model, ED-OR was a predictor of NON-THER (adjusted odds ratio 16.6; P < 0.001). One patient from ED-OR expired after complications from NON-THER. There were no deaths in the ADMIT group. For those patients with abdominal SWs who present with systolic blood pressure ≥110 mm Hg, no blood product transfusion in the emergency department and lacking evisceration, admission for serial abdominal exams may be preferred regardless of abdominal exam.


Assuntos
Traumatismos Abdominais/terapia , Gerenciamento Clínico , Lavagem Peritoneal/métodos , Ferimentos Perfurantes/terapia , Adulto , Serviço Hospitalar de Emergência , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
18.
Am Surg ; 81(10): 1080-3, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26463312

RESUMO

Blunt aortic injury (BAI) after chest trauma is a potentially lethal condition that requires rapid diagnosis for appropriate treatment. We compared CT with IV contrast (CTI) with CT with angiography (CTA) during the initial phase of care at an urban Level I trauma center from January 1, 2010 to December 31, 2013. Overall, 281 patients met inclusion criteria with 167 (59%) CTI and 114 (41%) CTA. There were no differences between cohorts in age, gender, initial heart rate, systolic blood pressure, and Glasgow Coma Scale. Mortality rates were similar for CTI and CTA (4% vs 8%, P = 0.20). CTI identified any chest injury in 54 per cent of patients compared with 46 per cent with CTA (P = 0.05). The rate of BAI was similar with CTI and CTA (2% vs 2%, P = 0.80), and neither modality was falsely negative. We conclude that CTI and CTA are similar at evaluating trauma patients for BAI, although CTI may be preferable during the initial assessment phase because the contrast injection may be combined with abdominal scanning and image time is reduced when whole-body CT is required.


Assuntos
Angiografia/métodos , Meios de Contraste , Radiografia Torácica/métodos , Traumatismos Torácicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Centros de Traumatologia , Ferimentos não Penetrantes/diagnóstico por imagem , Adulto , California/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Traumatismos Torácicos/mortalidade , Ferimentos não Penetrantes/mortalidade
19.
J Am Coll Surg ; 221(1): 17-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25899735

RESUMO

BACKGROUND: We sought to investigate the incidence of abdominal injuries in "found down" trauma patients to better understand the value of emergency department (ED) imaging. Found down patients are at high risk for injuries to the head or neck and low risk to the abdomen or pelvis, so imaging with CT of the abdomen/pelvis (AP) or Focused Assessment with Sonography for Trauma (FAST) is of questionable value. STUDY DESIGN: The trauma registry was queried over a 10-year period ending December 2013 for found down patients. Demographics, CT AP, FAST scans, and injuries were abstracted from the trauma registry and then through a confirmatory chart review. The primary outcome was significant abdominal or pelvis injury, defined as abdomen/pelvis Abbreviated Injury Scale (AIS) ≥ 3 or an abdominal injury that required operative intervention. The secondary outcome was mortality due to abdominal injury. RESULTS: Of the 342 patients who met inclusion criteria, mean Glasgow Coma Scale (GCS) was 11.0, and 189 (60%) of those tested for alcohol were intoxicated. Abdominal imaging included: CT AP only, 88 (57%); FAST only, 37 (24%); and CT AP and FAST, 29 (19%). Neither CT AP nor FAST scan led to a change in treatment and no patient had abdomen/pelvis AIS ≥ 3. Overall mortality was 33 (10%).The 24 trauma deaths were attributed to serious head trauma (n = 16) or traumatic arrest in the ED (n = 8); the 9 medical deaths were due to cerebral vascular accident (n = 5) or sepsis (n = 4). CONCLUSIONS: Although patients found down have a high mortality, abdominal injuries identified by imaging are highly unlikely. Efforts should focus on rapidly identifying and treating other causes of mortality, especially trauma to the head and neck, or medical diagnoses such as cerebral vascular accident or sepsis.


Assuntos
Traumatismos Abdominais/diagnóstico , Traumatismo Múltiplo/diagnóstico , Inconsciência/etiologia , Escala Resumida de Ferimentos , Traumatismos Abdominais/diagnóstico por imagem , Traumatismos Abdominais/mortalidade , Adulto , Idoso , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/diagnóstico , Traumatismos Craniocerebrais/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/mortalidade , Lesões do Pescoço/complicações , Lesões do Pescoço/diagnóstico , Lesões do Pescoço/mortalidade , Sistema de Registros , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia
20.
Mol Cancer Ther ; 14(3): 713-26, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25552366

RESUMO

Although poorly understood, androgen receptor (AR) signaling is sustained despite treatment of prostate cancer with antiandrogens and potentially underlies development of incurable castrate-resistant prostate cancer. However, therapies targeting the AR signaling axis eventually fail when prostate cancer progresses to the castrate-resistant stage. Stat5a/b, a candidate therapeutic target protein in prostate cancer, synergizes with AR to reciprocally enhance the signaling of both proteins. In this work, we demonstrate that Stat5a/b sequesters antiandrogen-liganded (MDV3100, bicalutamide, flutamide) AR in prostate cancer cells and protects it against proteasomal degradation in prostate cancer. Active Stat5a/b increased nuclear levels of both unliganded and antiandrogen-liganded AR, as demonstrated in prostate cancer cell lines, xenograft tumors, and clinical patient-derived prostate cancer samples. Physical interaction between Stat5a/b and AR in prostate cancer cells was mediated by the DNA-binding domain of Stat5a/b and the N-terminal domain of AR. Moreover, active Stat5a/b increased AR occupancy of the prostate-specific antigen promoter and AR-regulated gene expression in prostate cancer cells. Mechanistically, both Stat5a/b genetic knockdown and antiandrogen treatment induced proteasomal degradation of AR in prostate cancer cells, with combined inhibition of Stat5a/b and AR leading to maximal loss of AR protein and prostate cancer cell viability. Our results indicate that therapeutic targeting of AR in prostate cancer using antiandrogens may be substantially improved by targeting of Stat5a/b.


Assuntos
Antagonistas de Androgênios/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores Androgênicos/metabolismo , Fator de Transcrição STAT5/antagonistas & inibidores , Proteínas Supressoras de Tumor/antagonistas & inibidores , Androgênios/metabolismo , Anilidas/farmacologia , Benzamidas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Flutamida/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Ligantes , Masculino , Nitrilas/farmacologia , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Antígeno Prostático Específico/genética , Neoplasias de Próstata Resistentes à Castração/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Compostos de Tosil/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA