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1.
Public Health ; 233: 65-73, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38850603

RESUMEN

OBJECTIVES: The objective of this study was to estimate prevalence of hepatitis C virus (HCV) exposure and infection among Indigenous and tribal populations globally. STUDY DESIGN: Systematic review and meta-analysis. METHODS: We systematically searched bibliographic databases and grey literature (1/01/2000-16/06/2022). Prevalence estimates were synthesised overall, by World Health Organization region and HCV-risk group. For studies with comparator populations, prevalence ratios were estimated and pooled. RESULTS: Ninety-two studies were included. Globally, among general Indigenous and tribal populations, the median prevalence of HCV antibody (HCV Ab) was 1.3% (interquartile range [IQR]: 0.3-3.8%, I2 = 98.5%) and HCV RNA was 0.4% (IQR: 0-1.3%, I2 = 96.1%). The Western Pacific Region had the highest prevalence (HCV Ab: median: 3.0% [IQR: 0.4-11.9%], HCV RNA: median 5.6% [IQR: 2.0-8.8%]). Prevalence was highest in people who injected drugs (HCV Ab: median: 59.5%, IQR: 51.5-67.6%, I2 = 96.6%; and HCV RNA: median: 29.4%, IQR: 21.8-35.2%, I2 = 97.2%). There was no association between HCV Ab prevalence and Indigenous/tribal status for general populations (prevalence ratio = 0.91; 95% CI: 0.56, 1.49) or key risk groups. CONCLUSIONS: Indigenous and tribal peoples from the Western Pacific Region and recognised at-risk sub-populations had higher HCV prevalence. HCV prevalence showed no association with Indigenous/tribal status. However, this review was limited by heterogeneity and poor quality of constituent studies, varying definitions of Indigenous/tribal status, regional data gaps, and limited studies on chronic infection (HCV RNA). Comprehensive quality evidence on HCV epidemiology in Indigenous and tribal peoples is needed to tailor preventive and treatment interventions so these populations are not left behind in elimination efforts.

3.
ACS Chem Biol ; 17(5): 1022-1029, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35467836

RESUMEN

Genetic code expansion has proven invaluable to the elucidation of functions of defined protein modifications through the site-specific incorporation of noncanonical amino acids. The use of nonhydrolyzable derivatives of post-translational modifications can greatly increase site stoichiometry and half-life. Investigating acetyllysine reader domain (bromodomain) interactions with acetylated nonhistone proteins is challenging due to the limited tools available and dynamic nature of this post-translational modification. Here, we demonstrate that bromodomains bind acetyllysine peptides and those substituted with an acetyllysine derivative, trifluoroacetyllysine, with similar affinity and selectivity. Importantly, both trifluoroacetyllysine and acetyllysine can be site-specifically incorporated into proteins expressed in bacterial and mammalian cells, and the strong electron-withdrawing trifluoro substituent makes the latter resistant to deacetylation by sirtuins (SIRTs). The controlled expression of SIRT-resistant, site-specifically acetylated transcription factors expands the set of available tools for determining the function of acetylation, and it serves as a template for investigating bromodomain interactions with acetylated transcription factors.


Asunto(s)
Lisina , Sirtuinas , Acetilación , Animales , Lisina/química , Mamíferos/metabolismo , Unión Proteica , Dominios Proteicos , Procesamiento Proteico-Postraduccional , Sirtuinas/metabolismo , Factores de Transcripción/metabolismo
4.
Eye (Lond) ; 34(12): 2197-2218, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32778738

RESUMEN

Congenital and childhood cataracts are uncommon but regularly seen in the clinics of most paediatric ophthalmology teams in the UK. They are often associated with profound visual loss and a large proportion have a genetic aetiology, some with significant extra-ocular comorbidities. Optimal diagnosis and treatment typically require close collaboration within multidisciplinary teams. Surgery remains the mainstay of treatment. A variety of surgical techniques, timings of intervention and options for optical correction have been advocated making management seem complex for those seeing affected children infrequently. This paper summarises the proceedings of two recent RCOphth paediatric cataract study days, provides a literature review and describes the current UK 'state of play' in the management of paediatric cataracts.


Asunto(s)
Extracción de Catarata , Catarata , Oftalmología , Catarata/terapia , Niño , Humanos , Reino Unido/epidemiología , Trastornos de la Visión/terapia
5.
Gen Comp Endocrinol ; 295: 113522, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32492383

RESUMEN

The crustacean hyperglycemic hormone (CHH) neuropeptide family has multiple functions in the regulation of hemolymph glucose levels, molting, ion, and water balance and reproduction. In crab species, three neuroendocrine tissues: the eyestalk ganglia (medulla terminalis X-organ and -sinus gland = ES), the pericardial organ (PO), and guts synthesize a tissue-specific isoforms of CHH neuropeptides. Recently the presence of the mandibular organ-inhibiting hormone (MOIH) was reported in the stomatogastric nervous system (STNS) that regulates the rhythmic muscle movements in esophagus, cardiac sac, gastric and pyloric ports of the foregut. In this study, we aimed to determine the presence of a tissue-specific CHH isoform in the Jonah crab, Cancer borealis using PCR with degenerate primers and 5', 3' rapid amplification of cDNA ends (RACE) in the ES. PO, and STNS. The analysis of CHH sequences shows that C. borealis has one type of CHH isoform, unlike other crab species. We also isolated the cDNA sequence of molt-inhibiting hormone (MIH) in the ES and MOIH in the ES and STNS. The presence of CHH, MOIH and MIH in the sinus gland of adult females and males is confirmed by using a dot-blot assay with the putative peaks collected from RP-HPLC and anti-Cancer sera for CHH, MIH, and MOIH. The present of crustacean female sex hormone (CFSH) in the sinus gland of adult females was examined with a dot-blot assay with anti-Callinectes CFSH serum. Levels of CHH, MOIH, and MIH in the sinus gland and their expressions in the eyestalk ganglia are estimated in the adult males, where CHH is the predominant form among these neuropeptides.


Asunto(s)
Proteínas de Artrópodos/genética , Braquiuros/genética , Regulación de la Expresión Génica , Hormonas de Invertebrados/genética , Proteínas del Tejido Nervioso/genética , Secuencia de Aminoácidos , Estructuras Animales/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Cromatografía de Fase Inversa , Clonación Molecular , ADN Complementario/metabolismo , Femenino , Hemolinfa/metabolismo , Masculino , Neuropéptidos/química , Neuropéptidos/genética , Neuropéptidos/metabolismo , Sistemas Neurosecretores/metabolismo
6.
Transl Psychiatry ; 10(1): 14, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-32066689

RESUMEN

Later sleep timing, circadian preference, and circadian rhythm timing predict worse outcomes across multiple domains, including mood disorders, substance use, impulse control, and cognitive function. Disturbed sleep is common among pregnant and postpartum women. We examined whether sleep timing during third trimester of pregnancy predicted postpartum symptoms of mania, depression, and obsessive-compulsive disorder (OCD). Fifty-one women with a previous, but not active, episode of unipolar or bipolar depression had symptoms evaluated and sleep recorded with wrist actigraphy at 33 weeks of gestation and 2, 6, and 16 weeks postpartum. Circadian phase was measured in a subset of women using salivary dim light melatonin onset (DLMO). We divided the sample into "early sleep" and "late sleep" groups using average sleep onset time at 33 weeks of gestation, defined by the median-split time of 11:27 p.m. The "late sleep" group reported significantly more manic and depressive symptoms at postpartum week 2. Longer phase angle between DLMO and sleep onset at 33 weeks was associated with more manic symptoms at postpartum week 2 and more obsessive-compulsive symptoms at week 6. Delayed sleep timing in this sample of at-risk women was associated with more symptoms of mania, depression, and OCD in the postpartum period. Sleep timing may be a modifiable risk factor for postpartum depression.


Asunto(s)
Depresión Posparto , Melatonina , Actigrafía , Ritmo Circadiano , Depresión Posparto/diagnóstico , Femenino , Humanos , Embarazo , Sueño
7.
J Intellect Disabil Res ; 64(3): 234-245, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31975473

RESUMEN

BACKGROUND: A new legal capacity act was introduced in Ireland in 2015. This study aimed to identify and critically examine key issues in the area of decision-making capacity from the perspective of psychologists working with adults with an intellectual disability. METHODS: A qualitative exploratory approach was employed, and the study was positioned in a social constructionist framework. Purposive and snowballing sampling methods were used to recruit 15 clinical psychologists working with adults with an intellectual disability. Data were collected with the use of individual semistructured interviews. Interview transcripts were analysed using a model of thematic analysis. RESULTS: Six themes were identified: (1) a presumption of capacity but a culture of incapacity, (2) supporting decision making as a process, (3) authenticity of decision making, (4) need for support and training, (5) contributions of psychology and (6) the way forward. CONCLUSIONS: Participants described that people with intellectual disabilities were often excluded from decision-making processes. They welcomed the functional approach to decision making, considered substituted decision making to be necessary within a support framework and described supporting decision making as a process. Systemic, resource and attitudinal challenges were identified.


Asunto(s)
Actitud del Personal de Salud , Toma de Decisiones , Discapacidad Intelectual , Competencia Mental , Personas con Discapacidades Mentales , Relaciones Profesional-Paciente , Adulto , Humanos , Irlanda , Competencia Mental/legislación & jurisprudencia , Personas con Discapacidades Mentales/legislación & jurisprudencia , Psicología , Investigación Cualitativa
8.
J Hosp Infect ; 103(4): 428-434, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31394145

RESUMEN

BACKGROUND: Infections account for 15% of neonatal deaths and one-tenth of maternal mortality globally. Evidence-based practices to prevent and control infection are essential to reduce newborn and maternal mortality. AIM: To identify the barriers and opportunities experienced by staff when implementing infection prevention and control (IPC) guidelines in maternity wards and delivery units in six health centres in two states in Nigeria. METHODS: A structured survey was undertaken in the maternity ward and delivery unit of six healthcare facilities to assess critical infrastructure and equipment. A survey was completed with the matron to assess staff practices and quality assurance procedures. Data were triangulated with qualitative data from interviews with facility staff. FINDINGS: Usable handwashing facilities - with water, functioning taps and soap available - were present in the delivery units of all six facilities, but were present in only one postnatal ward. All facilities were visibly clean, and staff demonstrated a strong will to comply with protocol. Areas of concern included effectiveness of training, inadequate availability of personal protective equipment, inadequate hand hygiene practices, and outdated procedures to reprocess re-usable medical equipment. CONCLUSION: Safe childbirth and postnatal care require comprehensive adherence to hand hygiene protocols and the use of disposable personal protective equipment. Financial, equipment and human resource constraints are obstacles to effective implementation of IPC in labour and delivery wards in the centres included in this study. Recommended interim measures include the introduction of champions to systematize step-down training and to monitor and provide feedback at facility level.


Asunto(s)
Infección Hospitalaria/prevención & control , Parto Obstétrico , Adhesión a Directriz/estadística & datos numéricos , Higiene de las Manos/métodos , Maternidades , Control de Infecciones/métodos , Utilización de Procedimientos y Técnicas/estadística & datos numéricos , Animales , Femenino , Humanos , Recién Nacido , Nigeria , Embarazo , Encuestas y Cuestionarios
9.
J Med Chem ; 61(20): 9301-9315, 2018 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-30289257

RESUMEN

The biological functions of the dual bromodomains of human transcription-initiation-factor TFIID subunit 1 (TAF1(1,2)) remain unknown, although TAF1 has been identified as a potential target for oncology research. Here, we describe the discovery of a potent and selective in vitro tool compound for TAF1(2), starting from a previously reported lead. A cocrystal structure of lead compound 2 bound to TAF1(2) enabled structure-based design and structure-activity-relationship studies that ultimately led to our in vitro tool compound, 27 (GNE-371). Compound 27 binds TAF1(2) with an IC50 of 10 nM while maintaining excellent selectivity over other bromodomain-family members. Compound 27 is also active in a cellular-TAF1(2) target-engagement assay (IC50 = 38 nM) and exhibits antiproliferative synergy with the BET inhibitor JQ1, suggesting engagement of endogenous TAF1 by 27 and further supporting the use of 27 in mechanistic and target-validation studies.


Asunto(s)
Bencimidazoles/metabolismo , Diseño de Fármacos , Sondas Moleculares/metabolismo , Factor de Transcripción TFIID/química , Factor de Transcripción TFIID/metabolismo , Humanos , Modelos Moleculares , Conformación Proteica , Dominios Proteicos
10.
Cell Rep ; 24(7): 1722-1729, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30110629

RESUMEN

Acetylation of histone H3 at lysine 27 is a well-defined marker of enhancer activity. However, the functional impact of this modification at enhancers is poorly understood. Here, we use a chemical genetics approach to acutely block the function of the cAMP response element binding protein (CREB) binding protein (CBP)/P300 bromodomain in models of hematological malignancies and describe a consequent loss of H3K27Ac specifically from enhancers, despite the continued presence of CBP/P300 at chromatin. Using this approach to dissect the role of H3K27Ac at enhancers, we identify a critical role for this modification in the production of enhancer RNAs and transcription of enhancer-regulated gene networks.


Asunto(s)
Elementos de Facilitación Genéticos , Histonas/metabolismo , Procesamiento Proteico-Postraduccional , ARN Neoplásico/genética , Factores de Transcripción p300-CBP/genética , Acetilación , Sitios de Unión , Línea Celular Tumoral , Cromatina/química , Cromatina/metabolismo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Histonas/genética , Humanos , Lisina/metabolismo , Unión Proteica , Dominios Proteicos , ARN Neoplásico/metabolismo , Transcripción Genética , Factores de Transcripción p300-CBP/metabolismo
11.
Dis Esophagus ; 31(6)2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29800270

RESUMEN

Thoracic epidural (TE) analgesia has been the standard of care for transthoracic esophagectomy patients since the 1990s. Multimodal anesthesia using intrathecal diamorphine, local anesthetic infusion catheters (LAC) into the paravertebral space and rectus sheaths and intravenous opioid postoperatively represent an alternative option for postoperative analgesia. While TE can provide excellent pain control, it may inhibit early postoperative recovery by causing hypotension and reducing mobilization. The aim of this study is to determine whether multimodal analgesia with LAC was effective with respect to adequate pain management, and compare its impact on hypotension and mobility. Patients receiving multimodal LAC analgesia were matched using propensity score matching to patients undergoing two-phase trans-thoracic esophagectomy with a TE over a two-year period (from January 2015 to December 2016). Postoperative endpoints that had been evaluated prospectively, including pain scores on movement and at rest, inotrope or vasoconstrictor requirements, and hypotension (systolic BP < 90 mmHg), were compared between cohorts. Out of 14 patients (13 male) that received LAC were matched to a cohort of 14 patients on age, sex, and comorbidity. Mean and maximum pain scores at rest and movement on postoperative days 0 to 3 were equivalent between the groups. In both cohorts, 50% of patients had a pain score of more than 7 on at least one occasion. Fewer patients in the LAC group required vasoconstrictor infusion (LAC: 36% vs. TE: 57%, P = 0.256) to maintain blood pressure or had episodes of hypotension (LAC: 43% vs. TE: 79%, P = 0.05). The LAC group was more able to ambulate on the first postoperative day (LAC: 64% vs. TE: 43%, P = 0.14) but these differences were not statistically significant. Within the epidural cohort, three patients had interruption of epidural due to dislodgement or failure of block compared to no disruption in the multimodal local anesthesia catheters group (P = 0.05). Therefore, multimodal anesthesia using spinal diamorphine with combined paravertebral and rectus sheath local anesthetic catheters appears to provide comparable pain relief post two-phase esophagectomy and may provide more reliable and safe analgesia than the current standard of care.


Asunto(s)
Analgesia Epidural/métodos , Analgesia/métodos , Analgésicos Opioides/administración & dosificación , Esofagectomía/efectos adversos , Heroína/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Toracotomía/efectos adversos , Anciano , Analgesia/instrumentación , Catéteres , Esofagectomía/métodos , Esofagectomía/rehabilitación , Femenino , Humanos , Inyecciones Espinales , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/etiología , Estudios Retrospectivos , Toracotomía/métodos , Toracotomía/rehabilitación , Resultado del Tratamiento
12.
Nat Commun ; 8(1): 862, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-29021563

RESUMEN

Members of the ISWI family of chromatin remodelers mobilize nucleosomes to control DNA accessibility and, in some cases, are required for recovery from DNA damage. However, it remains poorly understood how the non-catalytic ISWI subunits BAZ1A and BAZ1B might contact chromatin to direct the ATPase SMARCA5. Here, we find that the plant homeodomain of BAZ1A, but not that of BAZ1B, has the unusual function of binding DNA. Furthermore, the BAZ1A bromodomain has a non-canonical gatekeeper residue and binds relatively weakly to acetylated histone peptides. Using CRISPR-Cas9-mediated genome editing we find that BAZ1A and BAZ1B each recruit SMARCA5 to sites of damaged chromatin and promote survival. Genetic engineering of structure-designed bromodomain and plant homeodomain mutants reveals that reader modules of BAZ1A and BAZ1B, even when non-standard, are critical for DNA damage recovery in part by regulating ISWI factors loading at DNA lesions and supporting transcriptional programs required for survival.ISWI chromatin remodelers regulate DNA accessibility and have been implicated in DNA damage repair. Here, the authors uncover functions, in response to DNA damage, for the bromodomain of the ISWI subunit BAZ1B and for the non-canonical PHD and bromodomain modules of the paralog BAZ1A.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Daño del ADN , Factores de Transcripción/fisiología , Sistemas CRISPR-Cas , Línea Celular , Cromatina/metabolismo , ADN/metabolismo , Edición Génica , Humanos , Estructura Molecular , Factores de Transcripción/química
13.
Diabet Med ; 34(12): 1765-1772, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28856721

RESUMEN

AIMS: To determine key worries about hypoglycaemia among insulin-using adults with Type 2 diabetes using a focus group approach. METHODS: Thirteen focus groups were conducted in three diabetes outpatient care units and one peer support group was set up, in Germany. A total of 64 insulin-dependent adults with Type 2 diabetes (36.5% women, mean age 65.2 ± 11.0 years) discussed their worries about hypoglycaemia. The qualitative results were assigned into thematic categories using a bottom-up coding procedure. Participants completed the Hypoglycaemia Fear Survey and demographic measures were recorded. The results of the Hypoglycaemia Fear Survey were contrasted with the focus group findings to evaluate how accurately the Hypoglycaemia Fear Survey comprehensively captures features of fear of hypoglycaemia in Type 2 diabetes. RESULTS: Eight themes were identified: 'unconsciousness/death'; 'aloneness/ helplessness', 'fear of hurting somebody'; 'shame'; 'loss of physical control'; 'long-term complications'; 'diabetes self-management issues'; and 'impaired awareness'. A total of 30 participants (46.9%) scored ≥3 on at least one item of the Hypoglycaemia Fear Survey worry subscale, indicating elevated worries. The Hypoglycaemia Fear Survey comprehensively captured all identified themes. Self-efficacy with regard to diabetes self-management seemed to play an important role in fear of hypoglycaemia in Type 2 diabetes. CONCLUSIONS: Given that even subclinical worries can have negative effects on quality of life and diabetes self-management, emphasis should be placed on diabetes education; in particular, to help patients to develop self-efficacy concerning diabetes self-management. The Hypoglycaemia Fear Survey comprehensively captures hypoglycaemia worries in Type 2 diabetes. Additional assessment of self-efficacy might be beneficial to identify people at risk of developing hypoglycaemia worries.


Asunto(s)
Diabetes Mellitus Tipo 2/psicología , Miedo/psicología , Hipoglucemia/psicología , Adulto , Anciano , Concienciación , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Grupos Focales , Alemania/epidemiología , Humanos , Hipoglucemia/epidemiología , Hipoglucemia/etiología , Hipoglucemiantes/uso terapéutico , Masculino , Persona de Mediana Edad , Calidad de Vida , Autoeficacia , Factores Socioeconómicos
14.
ACS Med Chem Lett ; 8(7): 737-741, 2017 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-28740608

RESUMEN

The biological function of bromodomains, epigenetic readers of acetylated lysine residues, remains largely unknown. Herein we report our efforts to discover a potent and selective inhibitor of the bromodomain of cat eye syndrome chromosome region candidate 2 (CECR2). Screening of our internal medicinal chemistry collection led to the identification of a pyrrolopyridone chemical lead, and subsequent structure-based drug design led to a potent and selective CECR2 bromodomain inhibitor (GNE-886) suitable for use as an in vitro tool compound.

15.
Biochemistry ; 56(30): 4015-4027, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28692281

RESUMEN

Mycobacterium tuberculosis protein Rv0577 is a prominent antigen in tuberculosis patients, the component responsible for neutral red staining of virulent strains of M. tuberculosis, a putative component in a methylglyoxal detoxification pathway, and an agonist of toll-like receptor 2. It also has an amino acid sequence that is 36% identical to that of Streptomyces coelicolor AfsK-binding protein A (KbpA), a component in the complex secondary metabolite pathways in the Streptomyces genus. To gain insight into the biological function of Rv0577 and the family of KpbA kinase regulators, the crystal structure for Rv0577 was determined to a resolution of 1.75 Å, binding properties with neutral red and deoxyadenosine were surveyed, backbone dynamics were measured, and thermal stability was assayed by circular dichroism spectroscopy. The protein is composed of four approximate repeats with a ßαßßß topology arranged radially in consecutive pairs to form two continuous eight-strand ß-sheets capped on both ends with an α-helix. The two ß-sheets intersect in the center at roughly a right angle and form two asymmetric deep "saddles" that may serve to bind ligands. Nuclear magnetic resonance chemical shift perturbation experiments show that neutral red and deoxyadenosine bind to Rv0577. Binding to deoxyadenosine is weaker with an estimated dissociation constants of 4.1 ± 0.3 mM for saddle 1. Heteronuclear steady-state {1H}-15N nuclear Overhauser effect, T1, and T2 values were generally uniform throughout the sequence with only a few modest pockets of differences. Circular dichroism spectroscopy characterization of the thermal stability of Rv0577 indicated irreversible unfolding upon heating with an estimated melting temperature of 56 °C.


Asunto(s)
Proteínas Bacterianas/metabolismo , Desoxiadenosinas/metabolismo , Modelos Moleculares , Mycobacterium tuberculosis/metabolismo , Rojo Neutro/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Sitios de Unión , Proteínas Portadoras/química , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Dicroismo Circular , Cristalografía por Rayos X , Desoxiadenosinas/química , Calor/efectos adversos , Péptidos y Proteínas de Señalización Intracelular , Cinética , Ligandos , Conformación Molecular , Rojo Neutro/química , Isótopos de Nitrógeno , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Estabilidad Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Streptomyces coelicolor/metabolismo , Homología Estructural de Proteína
16.
Bioorg Med Chem Lett ; 27(15): 3534-3541, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28606761

RESUMEN

Bromodomain-containing protein 9 (BRD9), an epigenetic "reader" of acetylated lysines on post-translationally modified histone proteins, is upregulated in multiple cancer cell lines. To assess the functional role of BRD9 in cancer cell lines, we identified a small-molecule inhibitor of the BRD9 bromodomain. Starting from a pyrrolopyridone lead, we used structure-based drug design to identify a potent and highly selective in vitro tool compound 11, (GNE-375). While this compound showed minimal effects in cell viability or gene expression assays, it showed remarkable potency in preventing the emergence of a drug tolerant population in EGFR mutant PC9 cells treated with EGFR inhibitors. Such tolerance has been linked to an altered epigenetic state, and 11 decreased BRD9 binding to chromatin, and this was associated with decreased expression of ALDH1A1, a gene previously shown to be important in drug tolerance. BRD9 inhibitors may therefore show utility in preventing epigenetically-defined drug resistance.


Asunto(s)
Resistencia a Medicamentos/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Factores de Transcripción/antagonistas & inhibidores , Aldehído Deshidrogenasa/genética , Familia de Aldehído Deshidrogenasa 1 , Línea Celular Tumoral , Diseño de Fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Simulación del Acoplamiento Molecular , Piridonas/química , Piridonas/farmacología , Retinal-Deshidrogenasa , Factores de Transcripción/metabolismo
17.
Nat Chem Biol ; 12(7): 531-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27214401

RESUMEN

The KDM5 family of histone demethylases catalyzes the demethylation of histone H3 on lysine 4 (H3K4) and is required for the survival of drug-tolerant persister cancer cells (DTPs). Here we report the discovery and characterization of the specific KDM5 inhibitor CPI-455. The crystal structure of KDM5A revealed the mechanism of inhibition of CPI-455 as well as the topological arrangements of protein domains that influence substrate binding. CPI-455 mediated KDM5 inhibition, elevated global levels of H3K4 trimethylation (H3K4me3) and decreased the number of DTPs in multiple cancer cell line models treated with standard chemotherapy or targeted agents. These findings show that pretreatment of cancer cells with a KDM5-specific inhibitor results in the ablation of a subpopulation of cancer cells that can serve as the founders for therapeutic relapse.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Proteína 2 de Unión a Retinoblastoma/antagonistas & inhibidores , Antineoplásicos/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estructura Molecular , Proteína 2 de Unión a Retinoblastoma/metabolismo , Relación Estructura-Actividad
18.
ACS Med Chem Lett ; 7(5): 531-6, 2016 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-27190605

RESUMEN

CBP and EP300 are highly homologous, bromodomain-containing transcription coactivators involved in numerous cellular pathways relevant to oncology. As part of our effort to explore the potential therapeutic implications of selectively targeting bromodomains, we set out to identify a CBP/EP300 bromodomain inhibitor that was potent both in vitro and in cellular target engagement assays and was selective over the other members of the bromodomain family. Reported here is a series of cell-potent and selective probes of the CBP/EP300 bromodomains, derived from the fragment screening hit 4-methyl-1,3,4,5-tetrahydro-2H-benzo[b][1,4]diazepin-2-one.

19.
J Med Chem ; 59(11): 5391-402, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27219867

RESUMEN

The biological role played by non-BET bromodomains remains poorly understood, and it is therefore imperative to identify potent and highly selective inhibitors to effectively explore the biology of individual bromodomain proteins. A ligand-efficient nonselective bromodomain inhibitor was identified from a 6-methyl pyrrolopyridone fragment. Small hydrophobic substituents replacing the N-methyl group were designed directing toward the conserved bromodomain water pocket, and two distinct binding conformations were then observed. The substituents either directly displaced and rearranged the conserved solvent network, as in BRD4(1) and TAF1(2), or induced a narrow hydrophobic channel adjacent to the lipophilic shelf, as in BRD9 and CECR2. The preference of distinct substituents for individual bromodomains provided selectivity handles useful for future lead optimization efforts for selective BRD9, CECR2, and TAF1(2) inhibitors.


Asunto(s)
Histona Acetiltransferasas/antagonistas & inhibidores , Proteínas Nucleares/antagonistas & inhibidores , Piridonas/farmacología , Pirroles/farmacología , Factores Asociados con la Proteína de Unión a TATA/antagonistas & inhibidores , Factor de Transcripción TFIID/antagonistas & inhibidores , Factores de Transcripción/antagonistas & inhibidores , Agua/química , Sitios de Unión/efectos de los fármacos , Proteínas de Ciclo Celular , Relación Dosis-Respuesta a Droga , Transferencia Resonante de Energía de Fluorescencia , Fluorometría , Histona Acetiltransferasas/metabolismo , Humanos , Ligandos , Modelos Moleculares , Conformación Molecular , Proteínas Nucleares/metabolismo , Piridonas/síntesis química , Piridonas/química , Pirroles/síntesis química , Pirroles/química , Relación Estructura-Actividad , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/metabolismo , Factores de Transcripción/metabolismo
20.
Structure ; 23(10): 1801-1814, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26365797

RESUMEN

Bromodomains are epigenetic readers that are recruited to acetyllysine residues in histone tails. Recent studies have identified non-acetyl acyllysine modifications, raising the possibility that these might be read by bromodomains. Profiling the nearly complete human bromodomain family revealed that while most human bromodomains bind only the shorter acetyl and propionyl marks, the bromodomains of BRD9, CECR2, and the second bromodomain of TAF1 also recognize the longer butyryl mark. In addition, the TAF1 second bromodomain is capable of binding crotonyl marks. None of the human bromodomains tested binds succinyl marks. We characterized structurally and biochemically the binding to different acyl groups, identifying bromodomain residues and structural attributes that contribute to specificity. These studies demonstrate a surprising degree of plasticity in some human bromodomains but no single factor controlling specificity across the family. The identification of candidate butyryl- and crotonyllysine readers supports the idea that these marks could have specific physiological functions.


Asunto(s)
Histona Acetiltransferasas/química , Histonas/química , Lisina/química , Procesamiento Proteico-Postraduccional , Factores Asociados con la Proteína de Unión a TATA/química , Factor de Transcripción TFIID/química , Factores de Transcripción/química , Acilación , Sitios de Unión , Butiratos/química , Butiratos/metabolismo , Crotonatos/química , Crotonatos/metabolismo , Cristalografía por Rayos X , Epigénesis Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Cinética , Lisina/metabolismo , Modelos Moleculares , Análisis por Matrices de Proteínas , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Factores Asociados con la Proteína de Unión a TATA/genética , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/genética , Factor de Transcripción TFIID/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Agua/química , Agua/metabolismo
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