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1.
Semin Cell Dev Biol ; 143: 3-16, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35351374

RESUMO

Endurance exercise is well established to increase mitochondrial content and function in skeletal muscle, a process termed mitochondrial biogenesis. Current understanding is that exercise initiates skeletal muscle mitochondrial remodeling via modulation of cellular nutrient, energetic and contractile stress pathways. These subtle changes in the cellular milieu are sensed by numerous transduction pathways that serve to initiate and coordinate an increase in mitochondrial gene transcription and translation. The result of these acute signaling events is the promotion of growth and assembly of mitochondria, coupled to a greater capacity for aerobic ATP provision in skeletal muscle. The aim of this review is to highlight the acute metabolic events induced by endurance exercise and the subsequent molecular pathways that sense this transient change in cellular homeostasis to drive mitochondrial adaptation and remodeling.


Assuntos
Exercício Físico , Mitocôndrias , Mitocôndrias/metabolismo , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Adaptação Fisiológica/fisiologia , Homeostase
2.
Semin Thromb Hemost ; 50(3): 462-473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37984359

RESUMO

Thrombin, a pleiotropic enzyme involved in coagulation, plays a crucial role in both procoagulant and anticoagulant pathways. Thrombin converts fibrinogen into fibrin, initiates platelet activation, and promotes clot formation. Thrombin also activates anticoagulant pathways, indirectly inhibiting factors involved in coagulation. Tissue factor triggers thrombin generation, and the overexpression of thrombin in various cancers suggests that it is involved in tumor growth, angiogenesis, and metastasis. Increased thrombin generation has been observed in cancer patients, especially those with metastases. Thrombin exerts its effects through protease-activated receptors (PARs), particularly PAR-1 and PAR-2, which are involved in cancer progression, angiogenesis, and immunological responses. Thrombin-mediated signaling promotes angiogenesis by activating endothelial cells and platelets, thereby releasing proangiogenic factors. These functions of thrombin are well recognized and have been widely described. However, in recent years, intriguing new findings concerning the association between thrombin activity and cancer development have come to light, which justifies a review of this research. In particular, there is evidence that thrombin-mediated events interact with the immune system, and may regulate its response to tumor growth. It is also worth reevaluating the impact of thrombin on thrombocytes in conjunction with its multifaceted influence on tumor progression. Understanding the role of thrombin/PAR-mediated signaling in cancer and immunological responses is crucial, particularly in the context of developing immunotherapies. In this systematic review, we focus on the impact of the thrombin-related immune system response on cancer progression.


Assuntos
Neoplasias , Trombina , Humanos , Trombina/metabolismo , Células Endoteliais/metabolismo , Neoplasias/metabolismo , Receptor PAR-1/metabolismo , Sistema Imunitário/metabolismo , Sistema Imunitário/patologia , Anticoagulantes
3.
Occup Environ Med ; 81(2): 101-108, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38272665

RESUMO

OBJECTIVES: This study aims to determine (1) which providers in US healthcare systems order lead tests, why and at what frequency and (2) whether current patient population lead levels are predictive of clinical outcomes. METHODS: Retrospective medical record study of all blood lead tests in the Medical University of South Carolina healthcare system 2012-2016 and consequent evidence of central nervous system (CNS)-related disease across a potential 10-year window (2012-2022). RESULTS: Across 4 years, 9726 lead tests resulted for 7181 patients (49.0% female; 0-94 years), representing 0.2% of the hospital population. Most tests were for young (76.6%≤age 3) and non-Hispanic black (47.2%) and Hispanic (26.7%) patients. A wide variety of providers ordered tests; however, most were ordered by paediatrics, psychiatry, internal medicine and neurology. Lead levels ranged from ≤2.0 µg/dL (80.8%) to ≥10 µg/dL (0.8%; max 36 µg/dL). 201 children (3.1%) had initial lead levels over the reference value for case management at the time (5.0 µg/dL). Many high level children did not receive follow-up testing in the system (36.3%) and those that did often failed to see levels fall below 5.0 µg/dL (80.1%). Non-Hispanic black and Hispanic patients were more likely to see lead levels stay high or go up over time. Over follow-up, children with high lead levels were more likely to receive new attention-deficit/hyperactivity disorder and conduct disorder diagnoses and new psychiatric medications. No significant associations were found between lead test results and new CNS diagnoses or medications among adults. CONCLUSIONS: Hospital lead testing covers a small portion of patients but includes a wide range of ages, presentations and provider specialities. Lack of lead decline among many paediatric patients suggests there is room to improve provider guidance around when to test and follow-up.


Assuntos
Intoxicação por Chumbo , Chumbo , Criança , Humanos , Feminino , Pré-Escolar , Masculino , Intoxicação por Chumbo/epidemiologia , Seguimentos , Estudos Retrospectivos , Fatores de Risco , Atenção à Saúde
4.
Clin Radiol ; 79(9): 665-672, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38942706

RESUMO

In the rapidly evolving field of artificial intelligence (AI) for radiology, with a plethora of vendor options and use-cases and evidence claims to sift through, the pressing question is how to effectively implement the right tool for enhanced patient care? This article presents a structured approach to AI deployment, drawing from a comprehensive case study in South West London. We underscore the necessity of forming a dedicated AI team with a clear vision and assertive leadership to navigate such complexities. Central to our discussion is the significance of crafting an AI implementation plan, with an overarching aim to augment patient care, promote operational efficiency, and lay down standardized protocols for seamless AI adoption. By presenting a blueprint for AI implementation within the National Health Service (NHS), we intend to demystify the process for radiology departments across the UK, enabling them to make informed decisions and empowering their staff to embrace and leverage AI responsibly ensuring that patient welfare remains at the heart of innovation. Thus, having a framework to follow when implementing an AI solution that addresses a vision for scalable adoption, core team members with diversity of skillset, staff engagement and education, plan for vendor selection, and change management is crucial for success.


Assuntos
Inteligência Artificial , Medicina Estatal , Humanos , Londres , Medicina Estatal/organização & administração , Radiologia/organização & administração
5.
Mol Cell ; 62(4): 558-71, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27132940

RESUMO

Histone H2B monoubiquitination (H2Bub1) is centrally involved in gene regulation. The deubiquitination module (DUBm) of the SAGA complex is a major regulator of global H2Bub1 levels, and components of this DUBm are linked to both neurodegenerative diseases and cancer. Unexpectedly, we find that ablation of USP22, the enzymatic center of the DUBm, leads to a reduction, rather than an increase, in global H2bub1 levels. In contrast, depletion of non-enzymatic components, ATXN7L3 or ENY2, results in increased H2Bub1. These observations led us to discover two H2Bub1 DUBs, USP27X and USP51, which function independently of SAGA and compete with USP22 for ATXN7L3 and ENY2 for activity. Like USP22, USP51 and USP27X are required for normal cell proliferation, and their depletion suppresses tumor growth. Our results reveal that ATXN7L3 and ENY2 orchestrate activities of multiple deubiquitinating enzymes and that imbalances in these activities likely potentiate human diseases including cancer.


Assuntos
Neoplasias da Mama/enzimologia , Proliferação de Células , Enzimas Desubiquitinantes/metabolismo , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Carga Tumoral , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Enzimas Desubiquitinantes/genética , Endopeptidases/genética , Endopeptidases/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genótipo , Células HEK293 , Humanos , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Fenótipo , Interferência de RNA , Transdução de Sinais , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo , Fatores de Tempo , Fatores de Transcrição/genética , Transfecção , Ubiquitina Tiolesterase , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação
6.
Sleep Breath ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836925

RESUMO

PURPOSE: This study investigates the impact of patient characteristics and demographics on hospital charges for tonsillectomy as a treatment for pediatric obstructive sleep apnea (OSA). The aim is to identify potential disparities in hospital charges and contribute to efforts for equitable access to care. METHODS: Data from the 2016 Healthcare Cost and Utilization Project (HCUP) Kid Inpatient Database (KID) was analyzed. The sample included 3,304 pediatric patients undergoing tonsillectomy ± adenoidectomy for OSA. Variables such as age, race, length of stay, hospital region, residential location, payer information, and median household income were collected. The primary outcome variable was hospital charge. Statistical analyses, including t-tests, ANOVA, and multiple linear regression, were conducted. RESULTS: Among 3,304 pediatric patients undergoing tonsillectomy for OSA. The average total charges for tonsillectomy were $26,400, with a mean length of stay of 1.70 days. Significant differences in charges were observed based on patient race, hospital region, and payer information. No significant differences were found based on gender, discharge quarter, residential location, or median household income. Multiple linear regression showed race, hospital region, and residential location were significant predictors of total hospital charges. CONCLUSION: This study highlights the influence of patient demographics and regional factors on hospital charges for pediatric tonsillectomy in OSA cases. These findings underscore the importance of addressing potential disparities in healthcare access and resource allocation to ensure equitable care for children with OSA. Efforts should be made to promote fair and affordable treatment for all pediatric OSA patients, regardless of their demographic backgrounds.

7.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753479

RESUMO

Cellular metabolism in cancer is significantly altered to support the uncontrolled tumor growth. How metabolic alterations contribute to hormonal therapy resistance and disease progression in prostate cancer (PCa) remains poorly understood. Here we report a glutaminase isoform switch mechanism that mediates the initial therapeutic effect but eventual failure of hormonal therapy of PCa. Androgen deprivation therapy inhibits the expression of kidney-type glutaminase (KGA), a splicing isoform of glutaminase 1 (GLS1) up-regulated by androgen receptor (AR), to achieve therapeutic effect by suppressing glutaminolysis. Eventually the tumor cells switch to the expression of glutaminase C (GAC), an androgen-independent GLS1 isoform with more potent enzymatic activity, under the androgen-deprived condition. This switch leads to increased glutamine utilization, hyperproliferation, and aggressive behavior of tumor cells. Pharmacological inhibition or RNA interference of GAC shows better treatment effect for castration-resistant PCa than for hormone-sensitive PCa in vitro and in vivo. In summary, we have identified a metabolic function of AR action in PCa and discovered that the GLS1 isoform switch is one of the key mechanisms in therapeutic resistance and disease progression.


Assuntos
Antagonistas de Androgênios/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Glutaminase/genética , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios/uso terapêutico , Animais , Linhagem Celular Tumoral , Biologia Computacional , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glutaminase/metabolismo , Glutamina/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Camundongos , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Análise Serial de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Cardiovasc Nurs ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39007747

RESUMO

BACKGROUND: Predictors have not been determined of serum brain-derived neurotrophic factor (BDNF) levels among patients with heart failure (HF). OBJECTIVE: The primary purpose was to evaluate history of atrial fibrillation, age, gender, and left ventricular ejection fraction as predictors of serum BDNF levels at baseline, 10 weeks, and 4 and 8 months after baseline among patients with HF. METHODS: This study was a retrospective cohort analyses of 241 patients with HF. Data were retrieved from the patients' health records (coded history of atrial fibrillation, left ventricular ejection fraction), self-report (age, gender), and serum BDNF. Linear multiple regression analyses were conducted. RESULTS: One hundred three patients (42.7%) had a history of atrial fibrillation. History of atrial fibrillation was a significant predictor of serum BDNF levels at baseline (ß = -0.16, P = .016), 4 months (ß = -0.21, P = .005), and 8 months (ß = -0.19, P = .015). Older age was a significant predictor at 10 weeks (ß = -0.17, P = .017) and 4 months (ß = -0.15, P = .046). CONCLUSIONS: Prospective studies are needed to validate these results. Clinicians need to assess patients with HF for atrial fibrillation and include treatment of it in management plans.

9.
Int J Mol Sci ; 25(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38396800

RESUMO

Prostate cancer (PCa) remains a common cancer with high mortality in men due to its heterogeneity and the emergence of drug resistance. A critical factor contributing to its lethality is the presence of prostate cancer stem cells (PCSCs), which can self-renew, long-term propagate tumors, and mediate treatment resistance. MicroRNA-34a (miR-34a) has shown promise as an anti-PCSC therapeutic by targeting critical molecules involved in cancer stem cell (CSC) survival and functions. Despite extensive efforts, the development of miR-34a therapeutics still faces challenges, including non-specific delivery and delivery-associated toxicity. One emerging delivery approach is ligand-mediated conjugation, aiming to achieve specific delivery of miR-34a to cancer cells, thereby enhancing efficacy while minimizing toxicity. Folate-conjugated miR-34a (folate-miR-34a) has demonstrated promising anti-tumor efficacy in breast and lung cancers by targeting folate receptor α (FOLR1). Here, we first show that miR-34a, a TP53 transcriptional target, is reduced in PCa that harbors TP53 loss or mutations and that miR-34a mimic, when transfected into PCa cells, downregulated multiple miR-34a targets and inhibited cell growth. When exploring the therapeutic potential of folate-miR-34a, we found that folate-miR-34a exhibited impressive inhibitory effects on breast, ovarian, and cervical cancer cells but showed minimal effects on and targeted delivery to PCa cells due to a lack of appreciable expression of FOLR1 in PCa cells. Folate-miR-34a also did not display any apparent effect on PCa cells expressing prostate-specific membrane antigen (PMSA) despite the reported folate's binding capability to PSMA. These results highlight challenges in the specific delivery of folate-miR-34a to PCa due to a lack of target (receptor) expression. Our study offers novel insights into the challenges and promises within the field and casts light on the development of ligand-conjugated miR-34a therapeutics for PCa.


Assuntos
Ácido Fólico , Neoplasias Pulmonares , MicroRNAs , Neoplasias da Próstata , Humanos , Masculino , Linhagem Celular Tumoral , Proliferação de Células/genética , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Receptor 1 de Folato/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Ligantes , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MicroRNAs/metabolismo , MicroRNAs/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ácido Fólico/farmacologia , Ácido Fólico/uso terapêutico
10.
Curr Opin Lipidol ; 34(6): 252-258, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37594008

RESUMO

PURPOSE OF REVIEW: Lowering LDL-C has been shown to reduce ASCVD events, yet many ASCVD patients do not achieve their guideline-directed LDL-C goals leaving patients at increased risk of another ASCVD event. This review discusses implementation strategies to improve guideline-directed lipid management in patients with ASCVD focusing on the provider, patient, and system level. RECENT FINDINGS: At a provider level, under-prescribing of statin intensity due most often to statin intolerance, clinical inertia, insufficient monitoring of LDL-C levels, and the difficulty and cost of prescribing other lipid-lowering therapies such as the PCSK9 inhibitors leads to suboptimal cholesterol management in ASCVD patients. Patients concerns about medication side effects and lack of understanding of their ASCVD risk are causes of poor adherence to their lipid-lowering therapy as are barriers at a system level. SUMMARY: To improve cholesterol management in ASCVD patients will require an integrated approach targeting the provider, the patient and the system. There is a need for further education of clinicians on the importance of intensive LDL-C lowering in ASCVD patients and greater use of nonstatin LDL-C-lowering therapies for those patients on a maximally tolerated statin who have not achieved their guideline-directed LDL-C goal. This will require shared decision-making with a focus on patient education and patient-clinician communication so that the clinician's goals and aims align with that of the patient.


Assuntos
Anticolesterolemiantes , Aterosclerose , Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pró-Proteína Convertase 9/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , LDL-Colesterol , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/tratamento farmacológico , Colesterol , Aterosclerose/complicações , Aterosclerose/tratamento farmacológico , Anticolesterolemiantes/uso terapêutico
11.
Semin Cancer Biol ; 82: 68-93, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34844845

RESUMO

Prostate cancer (PCa) is a prevalent malignancy that occurs primarily in old males. Prostate tumors in different patients manifest significant inter-patient heterogeneity with respect to histo-morphological presentations and molecular architecture. An individual patient tumor also harbors genetically distinct clones in which PCa cells display intra-tumor heterogeneity in molecular features and phenotypic marker expression. This inherent PCa cell heterogeneity, e.g., in the expression of androgen receptor (AR), constitutes a barrier to the long-term therapeutic efficacy of AR-targeting therapies. Furthermore, tumor progression as well as therapeutic treatments induce PCa cell plasticity such that AR-positive PCa cells may turn into AR-negative cells and prostate tumors may switch lineage identity from adenocarcinomas to neuroendocrine-like tumors. This induced PCa cell plasticity similarly confers resistance to AR-targeting and other therapies. In this review, I first discuss PCa from the perspective of an abnormal organ development and deregulated cellular differentiation, and discuss the luminal progenitor cells as the likely cells of origin for PCa. I then focus on intrinsic PCa cell heterogeneity in treatment-naïve tumors with the presence of prostate cancer stem cells (PCSCs). I further elaborate on PCa cell plasticity induced by genetic alterations and therapeutic interventions, and present potential strategies to therapeutically tackle PCa cell heterogeneity and plasticity. My discussions will make it clear that, to achieve enduring clinical efficacy, both intrinsic PCa cell heterogeneity and induced PCa cell plasticity need to be targeted with novel combinatorial approaches.


Assuntos
Adenocarcinoma , Neoplasias da Próstata , Adenocarcinoma/genética , Linhagem Celular Tumoral , Plasticidade Celular , Humanos , Masculino , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
12.
Semin Cancer Biol ; 78: 90-103, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33979674

RESUMO

It is increasingly appreciated that cancer cell heterogeneity and plasticity constitute major barriers to effective clinical treatments and long-term therapeutic efficacy. Research in the past two decades suggest that virtually all treatment-naive human cancers harbor subsets of cancer cells that possess many of the cardinal features of normal stem cells. Such stem-like cancer cells, operationally defined as cancer stem cells (CSCs), are frequently quiescent and dynamically change and evolve during tumor progression and therapeutic interventions. Intrinsic tumor cell heterogeneity is reflected in a different aspect in that tumors also harbor a population of slow-cycling cells (SCCs) that are not in the proliferative cell cycle and thus are intrinsically refractory to anti-mitotic drugs. In this Perspective, we focus our discussions on SCCs in cancer and on various methodologies that can be employed to enrich and purify SCCs, compare the similarities and differences between SCCs, CSCs and cancer cells undergoing EMT, and present evidence for the involvement of SCCs in surviving anti-neoplastic treatments, mediating tumor relapse, maintaining tumor dormancy and mediating metastatic dissemination. Our discussions make it clear that an in-depth understanding of the biological properties of SCCs in cancer will be instrumental to developing new therapeutic strategies to prevent tumor relapse and distant metastasis.


Assuntos
Ciclo Celular , Neoplasias/etiologia , Neoplasias/metabolismo , Microambiente Tumoral , Animais , Gerenciamento Clínico , Suscetibilidade a Doenças , Resistencia a Medicamentos Antineoplásicos , Humanos , Metástase Neoplásica , Neoplasias/patologia , Neoplasias/terapia , Prognóstico , Recidiva
13.
Semin Cancer Biol ; 82: 120-133, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33476721

RESUMO

LRIG1, leucine-rich repeats and immunoglobulin-like domains protein 1, was discovered more than 20 years ago and has been shown to be downregulated or lost, and to function as a tumor suppressor in several cancers. Another well-reported biological function of LRIG1 is to regulate and help enforce the quiescence of adult stem cells (SCs). In both contexts, LRIG1 regulates SC quiescence and represses tumor growth via, primarily, antagonizing the expression and activities of ERBB and other receptor tyrosine kinases (RTKs). We have recently reported that in treatment-naïve human prostate cancer (PCa), LRIG1 is primarily regulated by androgen receptor (AR) and is prominently overexpressed. In castration-resistant PCa (CRPC), both LRIG1 and AR expression becomes heterogeneous and, frequently, discordant. Importantly, in both androgen-dependent PCa and CRPC models, LRIG1 exhibits tumor-suppressive functions. Moreover, LRIG1 induction inhibits the growth of pre-established AR+ and AR- PCa. Here, upon a brief introduction of the LRIG1 and the LRIG family, we provide an updated overview on LRIG1 functions in regulating SC quiescence and repressing tumor development. We further highlight the expression, regulation and functions of LRIG1 in treatment-naïve PCa and CRPC. We conclude by offering the perspectives of identifying novel cancer-specific LRIG1-interacting signaling partners and developing LRIG1-based anti-cancer therapeutics and diagnostic/prognostic biomarkers.


Assuntos
Glicoproteínas de Membrana , Neoplasias de Próstata Resistentes à Castração , Linhagem Celular Tumoral , Retroalimentação , Genes Supressores de Tumor , Humanos , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Células-Tronco/metabolismo
14.
Bioorg Med Chem ; 80: 117170, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36696875

RESUMO

Many new drugs have been approved over the past decade for rare or orphan diseases. The passage of the Orphan Drug Act (ODA) in 1983 has provided key economic and regulatory incentives to provide medicines for patients who are suffering from rare diseases that may not be commercially attractive for research and development. We have analyzed 497 novel drugs approved from 2010 - June 13, 2022, of which 220 were given orphan designation status. We discuss trends over this time period, potential risks for long development times, and provide example case studies of successful development and launch of novel drugs for rare diseases.


Assuntos
Doenças Metabólicas , Doenças Raras , Estados Unidos , Humanos , Doenças Raras/tratamento farmacológico , Aprovação de Drogas , United States Food and Drug Administration , Produção de Droga sem Interesse Comercial
15.
Nature ; 545(7652): 112-115, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28445455

RESUMO

Protease-activated receptors (PARs) are a family of G-protein-coupled receptors (GPCRs) that are irreversibly activated by proteolytic cleavage of the N terminus, which unmasks a tethered peptide ligand that binds and activates the transmembrane receptor domain, eliciting a cellular cascade in response to inflammatory signals and other stimuli. PARs are implicated in a wide range of diseases, such as cancer and inflammation. PARs have been the subject of major pharmaceutical research efforts but the discovery of small-molecule antagonists that effectively bind them has proved challenging. The only marketed drug targeting a PAR is vorapaxar, a selective antagonist of PAR1 used to prevent thrombosis. The structure of PAR1 in complex with vorapaxar has been reported previously. Despite sequence homology across the PAR isoforms, discovery of PAR2 antagonists has been less successful, although GB88 has been described as a weak antagonist. Here we report crystal structures of PAR2 in complex with two distinct antagonists and a blocking antibody. The antagonist AZ8838 binds in a fully occluded pocket near the extracellular surface. Functional and binding studies reveal that AZ8838 exhibits slow binding kinetics, which is an attractive feature for a PAR2 antagonist competing against a tethered ligand. Antagonist AZ3451 binds to a remote allosteric site outside the helical bundle. We propose that antagonist binding prevents structural rearrangements required for receptor activation and signalling. We also show that a blocking antibody antigen-binding fragment binds to the extracellular surface of PAR2, preventing access of the tethered ligand to the peptide-binding site. These structures provide a basis for the development of selective PAR2 antagonists for a range of therapeutic uses.


Assuntos
Receptor PAR-2/química , Receptor PAR-2/metabolismo , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico/efeitos dos fármacos , Anticorpos Bloqueadores/química , Anticorpos Bloqueadores/farmacologia , Benzimidazóis/química , Benzimidazóis/farmacologia , Benzodioxóis/química , Benzodioxóis/farmacologia , Álcoois Benzílicos/química , Álcoois Benzílicos/farmacologia , Cristalografia por Raios X , Humanos , Imidazóis/química , Imidazóis/farmacologia , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/farmacologia , Cinética , Ligantes , Modelos Moleculares , Receptor PAR-2/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
16.
Arch Womens Ment Health ; 26(4): 495-501, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37286883

RESUMO

One in four US women will experience a completed or attempted rape in their lifetime, and more than 50% of survivors will experience two or more rapes. Rape and physical violence also co-occur. Multiple experiences of sexual and physical violence are associated with elevated mental and physical health problems. This secondary analysis examined the prevalence and correlates of experiencing sexual or physical violence within 6 months of a sexual assault medical forensic exam (SAMFE). Between May 2009 and December 2013, 233 female rape survivors aged 15 and older were enrolled in a randomized controlled trial during a SAMFE in the emergency department (ED). Demographics, rape characteristics, distress at the ED, and pre-rape history of sexual or physical victimization were assessed. New sexual and physical victimization was assessed 6 months after the SAMFE via telephone interview. Six months after the exam, 21.7% reported a new sexual or physical victimization. Predictors of revictimization during follow-up included sexual or physical victimization prior to the index rape, making less than $10,000 annually, remembering the rape well, life threat during the rape, and higher distress at the ED. In adjusted models, only pre-rape victimization and making less than $10,000 annually were associated with revictimization. Factors assessed at the ED can inform subsequent victimization risk. More research is needed to prevent revictimization among recent rape victims. Policies to provide financial support to recent rape victims and/or targeted prevention for those with pre-rape victimization at the SAMFE could reduce revictimization risk. TRIAL REGISTRATION: NCT01430624.


Assuntos
Vítimas de Crime , Estupro , Delitos Sexuais , Feminino , Humanos , Comportamento Sexual , Exame Físico
17.
EMBO J ; 37(12)2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29789392

RESUMO

To exploit vulnerabilities of tumors, it is urgent to identify associated defects in genome maintenance. One unsolved problem is the mechanism of regulation of DNA double-strand break repair by REV7 in complex with 53BP1 and RIF1, and its influence on repair pathway choice between homologous recombination and non-homologous end-joining. We searched for REV7-associated factors in human cells and found FAM35A, a previously unstudied protein with an unstructured N-terminal region and a C-terminal region harboring three OB-fold domains similar to single-stranded DNA-binding protein RPA, as novel interactor of REV7/RIF1/53BP1. FAM35A re-localized in damaged cell nuclei, and its knockdown caused sensitivity to DNA-damaging agents. In a BRCA1-mutant cell line, however, depletion of FAM35A increased resistance to camptothecin, suggesting that FAM35A participates in processing of DNA ends to allow more efficient DNA repair. We found FAM35A absent in one widely used BRCA1-mutant cancer cell line (HCC1937) with anomalous resistance to PARP inhibitors. A survey of FAM35A alterations revealed that the gene is altered at the highest frequency in prostate cancers (up to 13%) and significantly less expressed in metastatic cases, revealing promise for FAM35A as a therapeutically relevant cancer marker.


Assuntos
Proteína BRCA1/deficiência , Biomarcadores Tumorais/metabolismo , Dano ao DNA , Reparo do DNA , DNA de Neoplasias/metabolismo , Proteínas Mad2/metabolismo , Neoplasias/metabolismo , Proteínas/metabolismo , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Proteínas de Ligação a DNA , Células HEK293 , Humanos , Proteínas Mad2/genética , Mutação , Neoplasias/genética , Neoplasias/patologia , Proteínas/genética , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
18.
Am J Hum Genet ; 104(5): 914-924, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-30982611

RESUMO

Glypicans are a family of cell-surface heparan sulfate proteoglycans that regulate growth-factor signaling during development and are thought to play a role in the regulation of morphogenesis. Whole-exome sequencing of the Australian family that defined Keipert syndrome (nasodigitoacoustic syndrome) identified a hemizygous truncating variant in the gene encoding glypican 4 (GPC4). This variant, located in the final exon of GPC4, results in premature termination of the protein 51 amino acid residues prior to the stop codon, and in concomitant loss of functionally important N-linked glycosylation (Asn514) and glycosylphosphatidylinositol (GPI) anchor (Ser529) sites. We subsequently identified seven affected males from five additional kindreds with novel and predicted pathogenic variants in GPC4. Segregation analysis and X-inactivation studies in carrier females provided supportive evidence that the GPC4 variants caused the condition. Furthermore, functional studies of recombinant protein suggested that the truncated proteins p.Gln506∗ and p.Glu496∗ were less stable than the wild type. Clinical features of Keipert syndrome included a prominent forehead, a flat midface, hypertelorism, a broad nose, downturned corners of mouth, and digital abnormalities, whereas cognitive impairment and deafness were variable features. Studies of Gpc4 knockout mice showed evidence of the two primary features of Keipert syndrome: craniofacial abnormalities and digital abnormalities. Phylogenetic analysis demonstrated that GPC4 is most closely related to GPC6, which is associated with a bone dysplasia that has a phenotypic overlap with Keipert syndrome. Overall, we have shown that pathogenic variants in GPC4 cause a loss of function that results in Keipert syndrome, making GPC4 the third human glypican to be linked to a genetic syndrome.


Assuntos
Surdez/congênito , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Variação Genética , Glipicanas/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Deformidades Congênitas das Extremidades Inferiores/patologia , Adulto , Criança , Pré-Escolar , Surdez/genética , Surdez/patologia , Feminino , Humanos , Lactente , Masculino , Linhagem , Fenótipo , Adulto Jovem
19.
Development ; 146(4)2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30718289

RESUMO

USP22, a component of the SAGA complex, is overexpressed in highly aggressive cancers, but the normal functions of this deubiquitinase are not well defined. We determined that loss of USP22 in mice results in embryonic lethality due to defects in extra-embryonic placental tissues and failure to establish proper vascular interactions with the maternal circulatory system. These phenotypes arise from abnormal gene expression patterns that reflect defective kinase signaling, including TGFß and several receptor tyrosine kinase pathways. USP22 deletion in endothelial cells and pericytes that are induced from embryonic stem cells also hinders these signaling cascades, with detrimental effects on cell survival and differentiation as well as on the ability to form vessels. Our findings provide new insights into the functions of USP22 during development that may offer clues to its role in disease states.


Assuntos
Endopeptidases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Placenta/metabolismo , Transdução de Sinais , Animais , Sistema Cardiovascular/metabolismo , Diferenciação Celular , Sobrevivência Celular , Membrana Corioalantoide/metabolismo , Orelha Interna/embriologia , Células-Tronco Embrionárias/metabolismo , Células Endoteliais/metabolismo , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Camundongos , Fenótipo , Gravidez , Processamento de Proteína Pós-Traducional , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Ubiquitina Tiolesterase
20.
J Card Fail ; 28(4): 519-530, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34763080

RESUMO

BACKGROUND: The objective of this 3-arm randomized controlled trial was to evaluate the efficacy of computerized cognitive training (CCT) in improving primary outcomes of delayed-recall memory and serum brain-derived neurotrophic factor (BDNF) levels; and the secondary outcomes were working memory, instrumental activities of daily living (IADLs) and health-related quality of life (HRQL) in patients with heart failure (HF). METHODS AND RESULTS: Patients (n = 256) were randomly assigned to 8 weeks of CCT using BrainHQ, computerized crossword puzzles active control intervention, and usual care. All patients received weekly nurse-enhancement interventions. Data were collected at enrollment and baseline visits and at 10 weeks and 4 and 8 months. In mixed effects models, there were no statistically significant group or group-by-time differences in outcomes. There were statistically significant differences over time in all outcomes in all groups. Patients improved over time on measures of delayed-recall memory, working memory, IADLs, and HRQL and had decreased serum BDNF. CONCLUSIONS: CCT did not improve outcomes compared with the active control intervention and usual care. Nurse-enhancement interventions may have led to improved outcomes over time. Future studies are needed to test nurse-enhancement interventions in combination with other cognitive interventions to improve memory in persons with HF.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Insuficiência Cardíaca , Atividades Cotidianas , Cognição , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Humanos , Qualidade de Vida
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