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1.
EMBO J ; 42(7): e110496, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36843541

RESUMEN

Aberrant splicing is typically attributed to splice-factor (SF) mutation and contributes to malignancies including acute myeloid leukemia (AML). Here, we discovered a mutation-independent means to extensively reprogram alternative splicing (AS). We showed that the dysregulated expression of eukaryotic translation initiation factor eIF4E elevated selective splice-factor production, thereby impacting multiple spliceosome complexes, including factors mutated in AML such as SF3B1 and U2AF1. These changes generated a splicing landscape that predominantly supported altered splice-site selection for ~800 transcripts in cell lines and ~4,600 transcripts in specimens from high-eIF4E AML patients otherwise harboring no known SF mutations. Nuclear RNA immunoprecipitations, export assays, polysome analyses, and mutational studies together revealed that eIF4E primarily increased SF production via its nuclear RNA export activity. By contrast, eIF4E dysregulation did not induce known SF mutations or alter spliceosome number. eIF4E interacted with the spliceosome and some pre-mRNAs, suggesting its direct involvement in specific splicing events. eIF4E induced simultaneous effects on numerous SF proteins, resulting in a much larger range of splicing alterations than in the case of mutation or dysregulation of individual SFs and providing a novel paradigm for splicing control and dysregulation.


Asunto(s)
Empalme Alternativo , Leucemia Mieloide Aguda , Humanos , Factores de Empalme de ARN/metabolismo , Factor 4E Eucariótico de Iniciación/metabolismo , Empalme del ARN , Factores Eucarióticos de Iniciación/genética , Leucemia Mieloide Aguda/genética , Mutación
2.
Blood ; 141(6): 567-578, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36399715

RESUMEN

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with historically poor outcomes and no worldwide consensus treatment approach. Unique among most hematologic malignancies for its frequent cutaneous involvement, BPDCN can also invade other extramedullary compartments, including the central nervous system. Generally affecting older adults, many patients are unfit to receive intensive chemotherapy, and although hematopoietic stem cell transplantation is preferred for younger, fit individuals, not all are eligible. One recent therapeutic breakthrough is that all BPDCNs express CD123 (IL3Rα) and that this accessible surface marker can be pharmacologically targeted. The first-in-class agent for BPDCN, tagraxofusp, which targets CD123, was approved in December 2018 in the United States for patients with BPDCN aged ≥2 years. Despite favorable response rates in the frontline setting, many patients still relapse in the setting of monotherapy, and outcomes in patients with relapsed/refractory BPDCN remain dismal. Therefore, novel approaches targeting both CD123 and other targets are actively being investigated. To begin to formally address the state of the field, we formed a new collaborative initiative, the North American BPDCN Consortium (NABC). This group of experts, which includes a multidisciplinary panel of hematologists/oncologists, hematopoietic stem cell transplant physicians, pathologists, dermatologists, and pediatric oncologists, was tasked with defining the current standard of care in the field and identifying the most important research questions and future directions in BPDCN. The position findings of the NABC's inaugural meetings are presented herein.


Asunto(s)
Neoplasias Hematológicas , Trastornos Mieloproliferativos , Neoplasias Cutáneas , Niño , Humanos , Anciano , Nivel de Atención , Subunidad alfa del Receptor de Interleucina-3 , Células Dendríticas/patología , Recurrencia Local de Neoplasia/patología , Trastornos Mieloproliferativos/patología , Neoplasias Hematológicas/patología , Neoplasias Cutáneas/patología , Enfermedad Aguda , América del Norte
3.
Cardiol Young ; 34(4): 722-726, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37743785

RESUMEN

BACKGROUND: The Fontan procedure is considered one of the most remarkable achievements in paediatric cardiology and cardiac surgery. Its final anatomical objective is a venous return through the superior and inferior vena cava. The complications inherent to this procedure and subsequent failure are its limitations. OBJECTIVE: To describe the clinical and haemodynamic characteristics of patients with Fontan failure and define the risk factors associated with it, with its short- and long-term outcomes during a 21-year observation period. METHODS: This is a retrospective follow-up study in which 15 patients diagnosed with Fontan failure in the single-ventricle programme of a high-complexity hospital in Medellín, Colombia, between 2001 and 2022 were included. RESULTS: One hundred and eight patients were identified in whom the Fontan procedure was performed, and 17 met the failure criteria. 82.4% were men, with a median age of 4.3 years. Ebstein's anomaly was the most common diagnosis, 29.4%. All patients underwent Fontan with an extracardiac tube following the procedure. According to the type of failure, 58.8% of patients presented protein-losing enteropathy and 17.6% plastic bronchitis. During follow-up, 5.9% of patients died. CONCLUSION: Fontan surgery in our centre is an option for patients with univentricular physiology. The correct selection of the patient is essential to mitigate failure risks.


Asunto(s)
Procedimiento de Fontan , Cardiopatías Congénitas , Enteropatías Perdedoras de Proteínas , Niño , Masculino , Humanos , Preescolar , Femenino , Procedimiento de Fontan/efectos adversos , Procedimiento de Fontan/métodos , Colombia/epidemiología , Estudios de Seguimiento , Estudios Retrospectivos , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Factores de Riesgo , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Enteropatías Perdedoras de Proteínas/etiología
4.
Blood ; 137(6): 812-825, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-32911532

RESUMEN

B-cell lymphoma 6 (BCL6) is a transcription repressor and proto-oncogene that plays a crucial role in the innate and adaptive immune system and lymphoid neoplasms. However, its role in myeloid malignancies remains unclear. Here, we explored the role of BCL6 in acute myeloid leukemia (AML). BCL6 was expressed at variable and often high levels in AML cell lines and primary AML samples. AMLs with higher levels of BCL6 were generally sensitive to treatment with BCL6 inhibitors, with the exception of those with monocytic differentiation. Gene expression profiling of AML cells treated with a BCL6 inhibitor revealed induction of BCL6-repressed target genes and transcriptional programs linked to DNA damage checkpoints and downregulation of stem cell genes. Ex vivo treatment of primary AML cells with BCL6 inhibitors induced apoptosis and decreased colony-forming capacity, which correlated with the levels of BCL6 expression. Importantly, inhibition or knockdown of BCL6 in primary AML cells resulted in a significant reduction of leukemia-initiating capacity in mice, suggesting ablation of leukemia repopulating cell functionality. In contrast, BCL6 knockout or inhibition did not suppress the function of normal hematopoietic stem cells. Treatment with cytarabine further induced BCL6 expression, and the levels of BCL6 induction were correlated with resistance to cytarabine. Treatment of AML patient-derived xenografts with BCL6 inhibitor plus cytarabine suggested enhanced antileukemia activity with this combination. Hence, pharmacologic inhibition of BCL6 might provide a novel therapeutic strategy for ablation of leukemia-repopulating cells and increased responsiveness to chemotherapy.


Asunto(s)
Leucemia Mieloide Aguda/patología , Proteínas de Neoplasias/fisiología , Proteínas Proto-Oncogénicas c-bcl-6/fisiología , Animales , Antineoplásicos/farmacología , Apoptosis , Autorrenovación de las Células , Citarabina/uso terapéutico , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células Madre Hematopoyéticas/citología , Humanos , Indoles/farmacología , Indoles/uso terapéutico , Leucemia Mieloide Aguda/genética , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células Madre Neoplásicas/citología , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-bcl-6/antagonistas & inhibidores , Interferencia de ARN , ARN Mensajero/biosíntesis , ARN Mensajero/genética , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , RNA-Seq , Quimera por Radiación , Tiazolidinedionas/farmacología , Tiazolidinedionas/uso terapéutico , Ensayo de Tumor de Célula Madre , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Blood ; 138(26): 2753-2767, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34724563

RESUMEN

Measurable residual disease (MRD) is an important biomarker in acute myeloid leukemia (AML) that is used for prognostic, predictive, monitoring, and efficacy-response assessments. The European LeukemiaNet (ELN) MRD Working Party evaluated standardization and harmonization of MRD in an ongoing manner and has updated the 2018 ELN MRD recommendations based on significant developments in the field. New and revised recommendations were established during in-person and online meetings, and a 2-stage Delphi poll was conducted to optimize consensus. All recommendations are graded by levels of evidence and agreement. Major changes include technical specifications for next-generation sequencing-based MRD testing and integrative assessments of MRD irrespective of technology. Other topics include use of MRD as a prognostic and surrogate end point for drug testing; selection of the technique, material, and appropriate time points for MRD assessment; and clinical implications of MRD assessment. In addition to technical recommendations for flow- and molecular-MRD analysis, we provide MRD thresholds and define MRD response, and detail how MRD results should be reported and combined if several techniques are used. MRD assessment in AML is complex and clinically relevant, and standardized approaches to application, interpretation, technical conduct, and reporting are of critical importance.


Asunto(s)
Leucemia Mieloide Aguda/diagnóstico , Neoplasia Residual/diagnóstico , Europa (Continente) , Citometría de Flujo/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Leucemia Mieloide Aguda/genética , Neoplasia Residual/genética , Pronóstico
6.
Nat Chem Biol ; 17(7): 784-793, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34155404

RESUMEN

Polycomb repressive complex 1 (PRC1) is an essential chromatin-modifying complex that monoubiquitinates histone H2A and is involved in maintaining the repressed chromatin state. Emerging evidence suggests PRC1 activity in various cancers, rationalizing the need for small-molecule inhibitors with well-defined mechanisms of action. Here, we describe the development of compounds that directly bind to RING1B-BMI1, the heterodimeric complex constituting the E3 ligase activity of PRC1. These compounds block the association of RING1B-BMI1 with chromatin and inhibit H2A ubiquitination. Structural studies demonstrate that these inhibitors bind to RING1B by inducing the formation of a hydrophobic pocket in the RING domain. Our PRC1 inhibitor, RB-3, decreases the global level of H2A ubiquitination and induces differentiation in leukemia cell lines and primary acute myeloid leukemia (AML) samples. In summary, we demonstrate that targeting the PRC1 RING domain with small molecules is feasible, and RB-3 represents a valuable chemical tool to study PRC1 biology.


Asunto(s)
Complejo Represivo Polycomb 1/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Diferenciación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Células K562 , Modelos Moleculares , Estructura Molecular , Complejo Represivo Polycomb 1/genética , Complejo Represivo Polycomb 1/metabolismo , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Ubiquitinación/efectos de los fármacos
7.
Nature ; 551(7678): 95-99, 2017 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-29094698

RESUMEN

Pathogens have to balance transmission with persistence. For Plasmodium falciparum, the most widespread and virulent malaria parasite, persistence within its human host requires continuous asexual replication within red blood cells, while its mosquito-borne transmission depends on intra-erythrocytic differentiation into non-replicating sexual stages called gametocytes. Commitment to either fate is determined during the preceding cell cycle that begins with invasion by a single, asexually committed merozoite and ends, 48 hours later, with a schizont releasing newly formed merozoites, all committed to either continued asexual replication or differentiation into gametocytes. Sexual commitment requires the transcriptional activation of ap2-g (PF3D7_1222600), the master regulator of sexual development, from an epigenetically silenced state during asexual replication. AP2-G expression during this 'commitment cycle' prepares gene expression in nascent merozoites to initiate sexual development through a hitherto unknown mechanism. To maintain a persistent infection, the expression of ap2-g is limited to a sub-population of parasites (1-30%, depending on genetic background and growth conditions). As sexually committed schizonts comprise only a sub-population and are morphologically indistinguishable from their asexually committed counterparts, defining their characteristic gene expression has been difficult using traditional, bulk transcriptome profiling. Here we use highly parallel, single-cell RNA sequencing of malaria cultures undergoing sexual commitment to determine the transcriptional changes induced by AP2-G within this sub-population. By analysing more than 18,000 single parasite transcriptomes from a conditional AP2-G knockdown line and NF54 wild-type parasites at multiple stages of development, we show that sexually committed, AP2-G+ mature schizonts specifically upregulate additional regulators of gene expression, including other AP2 transcription factors, histone-modifying enzymes, and regulators of nucleosome positioning. These epigenetic regulators may act to facilitate the expression and/or repression of genes that are necessary for the initiation of gametocyte development in the subsequent cell cycle.


Asunto(s)
Gametogénesis/genética , Malaria/parasitología , Plasmodium falciparum/citología , Plasmodium falciparum/genética , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcriptoma/genética , Ciclo Celular , Femenino , Perfilación de la Expresión Génica , Histonas/metabolismo , Humanos , Masculino , Nucleosomas/genética , Nucleosomas/metabolismo , Plasmodium falciparum/crecimiento & desarrollo , Plasmodium falciparum/fisiología , Reproducción Asexuada , Esquizontes/citología , Esquizontes/genética , Factores de Transcripción/metabolismo
8.
Nature ; 538(7625): 397-401, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27706135

RESUMEN

Transient, multi-protein complexes are important facilitators of cellular functions. This includes the chaperome, an abundant protein family comprising chaperones, co-chaperones, adaptors, and folding enzymes-dynamic complexes of which regulate cellular homeostasis together with the protein degradation machinery. Numerous studies have addressed the role of chaperome members in isolation, yet little is known about their relationships regarding how they interact and function together in malignancy. As function is probably highly dependent on endogenous conditions found in native tumours, chaperomes have resisted investigation, mainly due to the limitations of methods needed to disrupt or engineer the cellular environment to facilitate analysis. Such limitations have led to a bottleneck in our understanding of chaperome-related disease biology and in the development of chaperome-targeted cancer treatment. Here we examined the chaperome complexes in a large set of tumour specimens. The methods used maintained the endogenous native state of tumours and we exploited this to investigate the molecular characteristics and composition of the chaperome in cancer, the molecular factors that drive chaperome networks to crosstalk in tumours, the distinguishing factors of the chaperome in tumours sensitive to pharmacologic inhibition, and the characteristics of tumours that may benefit from chaperome therapy. We find that under conditions of stress, such as malignant transformation fuelled by MYC, the chaperome becomes biochemically 'rewired' to form a network of stable, survival-facilitating, high-molecular-weight complexes. The chaperones heat shock protein 90 (HSP90) and heat shock cognate protein 70 (HSC70) are nucleating sites for these physically and functionally integrated complexes. The results indicate that these tightly integrated chaperome units, here termed the epichaperome, can function as a network to enhance cellular survival, irrespective of tissue of origin or genetic background. The epichaperome, present in over half of all cancers tested, has implications for diagnostics and also provides potential vulnerability as a target for drug intervention.


Asunto(s)
Chaperonas Moleculares/metabolismo , Complejos Multiproteicos/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Descubrimiento de Drogas , Femenino , Genes myc/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Ratones , Chaperonas Moleculares/antagonistas & inhibidores , Complejos Multiproteicos/antagonistas & inhibidores , Complejos Multiproteicos/química , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Especificidad de Órganos
9.
Molecules ; 27(9)2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35566279

RESUMEN

A method to identify anticancer compounds in plants was proposed based on the hypothesis that these compounds are primarily present in plants to provide them with an ecological advantage over neighboring plants and other competitors. According to this view, identifying plants that contain compounds that inhibit or interfere with the development of other plant species may facilitate the discovery of novel anticancer agents. The method was developed and tested using Magnolia grandiflora, Gynoxys verrucosa, Picradeniopsis oppositifolia, and Hedyosmum racemosum, which are plant species known to possess compounds with cytotoxic activities. Plant extracts were screened for growth inhibitory activity, and then a thin-layer chromatography bioautography assay was conducted. This located the major antileukemic compounds 1, 2, 4, and 5 in the extracts. Once the active compounds were located, they were extracted and purified, and their structures were determined. The growth inhibitory activity of the purified compounds showed a significant correlation with their antileukemic activity. The proposed approach is rapid, inexpensive, and can easily be implemented in areas of the world with high biodiversity but with less access to advanced facilities and biological assays.


Asunto(s)
Asteraceae , Asteraceae/química , Cromatografía en Capa Delgada , Extractos Vegetales/química , Extractos Vegetales/farmacología , Plantas
10.
Eur J Neurosci ; 54(6): 6075-6092, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34308559

RESUMEN

Disruptions in social behaviour are prevalent in many neuropsychiatric disorders such as schizophrenia, bipolar disorder and autism spectrum disorders. However, the underlying neurochemical regulation of social behaviour is still not well understood. The central cholinergic system has been proposed to contribute to the regulation of social behaviour. For instance, decreased global levels of acetylcholine release in the brain leads to decreased social interaction and an impairment of social memory in mice. Nonetheless, it has been difficult to ascertain the specific brain areas where cholinergic signalling influences social preference and social memory. In this study, we investigated the impact of different forebrain cholinergic regions on social behaviour by examining mouse lines that differ in their regional expression level of the vesicular acetylcholine transporter-the protein that regulates acetylcholine secretion. We found that when cholinergic signalling is highly disrupted in the striatum, hippocampus, cortex and amygdala mice have intact social preference but are impaired in social memory, as they cannot remember a familiar conspecific nor recognize a novel one. A similar pattern emerges when acetylcholine release is disrupted mainly in the striatum, cortex, and amygdala; however, the ability to recognize novel conspecifics is retained. In contrast, cholinergic signalling of the striatum and amygdala does not appear to significantly contribute to the modulation of social memory and social preference. Furthermore, we demonstrated that increasing global cholinergic tone does not increase social behaviours. Together, these data suggest that cholinergic transmission from the hippocampus and cortex are important for regulating social memory.


Asunto(s)
Prosencéfalo Basal , Acetilcolina , Animales , Colinérgicos , Hipocampo/metabolismo , Masculino , Ratones , Proteínas de Transporte Vesicular de Acetilcolina/metabolismo
11.
World J Surg ; 45(4): 1043-1052, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33151371

RESUMEN

BACKGROUND: Damage control surgery (DCS) has emerged as a new option in the management of non-traumatic peritonitis patients to increase survival in critically ill patients. The purpose of this study was to compare DCS with conventional strategy (anastomosis/ostomies in the index laparotomy) for severe non-traumatic peritonitis regarding postoperative complications, ostomy rate, and mortality and to propose a useful algorithm in the clinical practice. METHODS: Patients who underwent an urgent laparotomy for non-trauma peritonitis at a single level I trauma center in Colombia between January 2003 and December 2018, were retrospectively included. We compared patients who had DCS management versus definitive initial surgical management (DISM) group. We evaluated clinical outcomes and morbidities among groups. RESULTS: 290 patients were included; 81 patients were treated with DCS and 209 patients underwent DISM. Patients treated with DCS had a worse critical status before surgery with higher SOFA score [median, DCS group: 5 (IQR: 3-8) vs. DISM group: 3 (IQR: 1-6), p < 0.001]. The length of hospital stay and overall mortality rate of DCS group were not significant statistical differences with DISM group. Complications rate related to primary anastomosis or primary ostomy was similar. There is not difference in ostomy rate among groups. At multivariate analysis, SOFA > 6 points and APACHE-II > 20 points correlated with a higher probability of DCS. CONCLUSION: DCS in severe non-trauma peritonitis patients is feasible and safe as surgical strategy management without increasing mortality, length hospital of stay, or complications. DCS principles might be applied in the non-trauma scenarios without increase the stoma rate.


Asunto(s)
Peritonitis , APACHE , Algoritmos , Colombia , Humanos , Peritonitis/etiología , Peritonitis/cirugía , Estudios Retrospectivos
12.
BMC Vet Res ; 17(1): 217, 2021 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-34118903

RESUMEN

BACKGROUND: Worldwide, Porcine Reproductive and Respiratory Syndrome (PRRS) is among the diseases that cause the highest economic impact in modern pig production. PRRS was first detected in Costa Rica in 1996 and has since then severely affected the local swine industry. Studies of the molecular characterization of circulating strains, correlation with clinical records, and associations with pathogens associated with Porcine Respiratory Disease Complex (PRDC) have not been done in Costa Rica. RESULTS: Sequencing and phylogenetic analysis of ORF5 proved that PRRSV-2 was the only species detected in all locations analyzed. These sequences were grouped into three clusters. When comparing samples from San Jose, Alejuela, and Puntarenas to historical isolates of the previously described lineages (1 to 9), it has been shown that these were closely related to each other and belonged to Lineage 5, along with the samples from Heredia. Intriguingly, samples from Cartago clustered in a separate clade, phylogenetically related to Lineage 1. Epitope analysis conducted on the GP5 sequence of field isolates from Costa Rica revealed seven peptides with at least 80% amino acid sequence identity with previously described and experimentally validated immunogenic regions. Previously described epitopes A, B, and C, were detected in the Santa Barbara-Heredia isolate. CONCLUSIONS: Our data suggest that the virus has three distinct origins or introductions to the country. Future studies will elucidate how recently introduced vaccines will shape the evolutionary change of circulating field strains.


Asunto(s)
Sistemas de Lectura Abierta/genética , Virus del Síndrome Respiratorio y Reproductivo Porcino/clasificación , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Secuencia de Aminoácidos , Animales , Costa Rica/epidemiología , Epítopos/análisis , Filogenia , Síndrome Respiratorio y de la Reproducción Porcina/epidemiología , Síndrome Respiratorio y de la Reproducción Porcina/virología , Porcinos
13.
Public Health Nurs ; 38(2): 223-231, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33522011

RESUMEN

OBJECTIVE: Health inequities and disparities are associated with non-White race/ethnicity, immigrant status, income, and geographic location. Community engagement is essential to identify health and social needs and to plan health care and social services programs. To begin a larger community-based participatory study, the purpose of this study was to explore community residents' perceptions of barriers and facilitators to achieving and maintaining health. DESIGN, SAMPLE, AND MEASUREMENTS: This qualitative descriptive study used focus group interviews. We recruited a convenience sample (n = 50) from community meetings and gathering for five audio-recorded focus groups that used a semi-structured interview guide. Transcripts were coded to identify common topics in each group and major themes across groups. RESULTS: Participants were predominantly women (58%), Hispanic/Latinx, and Spanish-speaking (57%), who rented their homes (69%). Two main themes emerged: (a) social determinants as barriers to health and (b) need for trust to participate in health programs. CONCLUSIONS: Although health care providers are frequently concerned about providing access to care, community members identified a variety of social determinants that affected their health. Listening and responding to community members' priorities are the foundation to improving health in neighborhoods directly affected by inequities.


Asunto(s)
Emigrantes e Inmigrantes , Características de la Residencia , Atención a la Salud , Femenino , Grupos Focales , Humanos , Investigación Cualitativa
14.
Trop Anim Health Prod ; 53(4): 441, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34406521

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant economic losses to the swine industry worldwide. Little is known regarding the epidemiology of this infection in tropical countries. To address this problem in Costa Rica, a seroepidemiological study was carried out in two phases. In the first phase, a pilot study was conducted in nine farms with the clinical diagnosis of PRRSV. In total, 265 pig serum samples were collected from animals ranging in age from 1 to 15 weeks of age. This study aimed to establish the duration of maternal immunity in piglets, to identify the period of viremia, and to determine when seroconversion occurs. In the second phase, a cross-sectional serology study was performed on a representative sample of the Costa Rican national herds in the second phase. The twenty-five selected farms represent all provinces and were classified according to herd size (100 to 2000 sows). In each farm, pigs aged 8, 10, and 12 weeks were sampled, as well as gilts based on the pilot study. In total 1281 pigs were sampled across all 25 farms. The aim of the cross-sectional study was to quantify the seroprevalence of PRRSV in Costa Rican pig farms and to describe its geographical distribution in this tropical country. The prevalence of positive farms was 44% (11/25), and these farms were located in six of the seven provinces of Costa Rica. Overall, 58% (344/596) of the pigs were seropositive to PRRSV. The age of the pigs and the ecozone where farms were located were significantly related with PRRSV seroprevalence in animals and herds, respectively.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Animales , Anticuerpos Antivirales , Costa Rica/epidemiología , Estudios Transversales , Granjas , Femenino , Proyectos Piloto , Síndrome Respiratorio y de la Reproducción Porcina/epidemiología , Estudios Seroepidemiológicos , Porcinos
15.
J Biol Chem ; 294(6): 2162-2179, 2019 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-30409908

RESUMEN

The chaperome is the collection of proteins in the cell that carry out molecular chaperoning functions. Changes in the interaction strength between chaperome proteins lead to an assembly that is functionally and structurally distinct from each constituent member. In this review, we discuss the epichaperome, the cellular network that forms when the chaperome components of distinct chaperome machineries come together as stable, functionally integrated, multimeric complexes. In tumors, maintenance of the epichaperome network is vital for tumor survival, rendering them vulnerable to therapeutic interventions that target critical epichaperome network components. We discuss how the epichaperome empowers an approach for precision medicine cancer trials where a new target, biomarker, and relevant drug candidates can be correlated and integrated. We introduce chemical biology methods to investigate the heterogeneity of the chaperome in a given cellular context. Lastly, we discuss how ligand-protein binding kinetics are more appropriate than equilibrium binding parameters to characterize and unravel chaperome targeting in cancer and to gauge the selectivity of ligands for specific tumor-associated chaperome pools.


Asunto(s)
Antineoplásicos , Sistemas de Liberación de Medicamentos/métodos , Chaperonas Moleculares , Proteínas de Neoplasias , Neoplasias , Mapas de Interacción de Proteínas/efectos de los fármacos , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Humanos , Chaperonas Moleculares/antagonistas & inhibidores , Chaperonas Moleculares/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología
16.
Br J Haematol ; 190(6): 891-900, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32239670

RESUMEN

Leukaemic stem cells (LSC) have been experimentally defined as the leukaemia-propagating population and are thought to be the cellular reservoir of relapse in acute myeloid leukaemia (AML). Therefore, LSC measurements are warranted to facilitate accurate risk stratification. Previously, we published the composition of a one-tube flow cytometric assay, characterised by the presence of 13 important membrane markers for LSC detection. Here we present the validation experiments of the assay in several large AML research centres, both in Europe and the United States. Variability within instruments and sample processing showed high correlations between different instruments (Rpearson  > 0·91, P < 0·001). Multi-centre testing introduced variation in reported LSC percentages but was found to be below the clinical relevant threshold. Clear gating protocols resulted in all laboratories being able to perform LSC assessment of the validation set. Participating centres were nearly unanimously able to distinguish LSChigh (>0·03% LSC) from LSClow (<0·03% LSC) despite inter-laboratory variation in reported LSC percentages. This study proves that the LSC assay is highly reproducible. These results together with the high prognostic impact of LSC load at diagnosis in AML patients render the one-tube LSC assessment a good marker for future risk classification.


Asunto(s)
Citometría de Flujo , Leucemia Mieloide Aguda , Células Madre Neoplásicas , Adulto , Femenino , Humanos , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/patología , Masculino , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología
17.
Adv Exp Med Biol ; 1243: 87-99, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32297213

RESUMEN

The chaperome is a large family of proteins composed of chaperones, co-chaperones and a multitude of other factors. Elegant studies in yeast and other organisms have paved the road to how we currently understand the complex organization of this large family into protein networks. The goal of this chapter is to provide an overview of chaperome networks in cancer cells, with a focus on two cellular states defined by chaperome network organization. One state characterized by chaperome networks working in isolation and with little overlap, contains global chaperome networks resembling those of normal, non-transformed, cells. We propose that in this state, redundancy in chaperome networks results in a tumor type unamenable for single-agent chaperome therapy. The second state comprises chaperome networks interconnected in response to cellular stress, such as MYC hyperactivation. This is a state where no redundant pathways can be deployed, and is a state of vulnerability, amenable for chaperome therapy. We conclude by proposing a change in how we discover and implement chaperome inhibitor strategies, and suggest an approach to chaperome therapy where the properties of chaperome networks, rather than genetics or client proteins, are used in chaperome inhibitor implementation.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Chaperonas Moleculares/antagonistas & inhibidores , Chaperonas Moleculares/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Neoplasias/patología
18.
Molecules ; 25(20)2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-33092263

RESUMEN

Dehydroleucodine is a bioactive sesquiterpene lactone. Herein, four dehydroleucodine amino derivatives were synthesized using the amines proline, piperidine, morpholine, and tyramine, and spectroscopic methods and single-crystal X-ray diffraction unambiguously established their structures. The cytotoxic activity of these compounds was evaluated against eight acute myeloid leukemia cell lines, and their toxicity to peripheral blood mononuclear cells was also determined. The proline adduct was the most active compound, it showed anti-leukemic activity, upregulated heme oxygenase 1 (HMOX1) and the primary stress-inducible isoform of the heath shock 70 kDa protein 1 (HSPA1A), and downregulated NFkB1 transcription, it was also found to be about 270 times more water soluble than dehydroleucodine.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Lactonas/química , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Sesquiterpenos/química , Línea Celular Tumoral , Cristalografía por Rayos X , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/genética , Hemo-Oxigenasa 1/genética , Humanos , Lactonas/síntesis química , Lactonas/farmacología , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Morfolinas/química , Subunidad p50 de NF-kappa B/genética , Piperidinas/química , Sesquiterpenos/síntesis química , Sesquiterpenos/farmacología , Tiramina/química
19.
Blood ; 129(26): 3465-3475, 2017 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-28487292

RESUMEN

The Hedgehog (Hh) signaling pathway is activated in many cancers and is a promising target for therapeutic development. Deletions in the receptor Patched (PTCH) or activating mutations in Smoothened (SMO) have been reported in basal cell carcinoma and medulloblastoma, but are largely absent in most tumor types. Therefore, the mechanism of pathway activation in most cancers, including hematological malignancies, remains unknown. In normal tissues, Hh pathway activation via PTCH/SMO causes an increase in the downstream transcriptional activator GLI1 and a decrease in the GLI3 transcriptional repressor (GLI3R). In this article, we confirm that the Hh pathway is active in acute myeloid leukemia (AML), however, this activity is largely independent of SMO. Epigenetic and gene expression analysis of The Cancer Genome Atlas AML data set reveals that GLI3 expression is silenced in most AML patient samples, and the GLI3 locus is abnormally methylated. We show that GLI3R is required for the therapeutic effect of SMO antagonists in AML samples and restoration of GLI3R suppresses the growth of AML. We additionally demonstrate that GLI3R represses AML growth by downregulating AKT expression. In summary, this study provides the first evidence that GLI3R plays an essential role in SMO-independent Hh signaling in AML, and suggests that GLI3R could serve as a potential biomarker for patient selection in SMO antagonist clinical trials. Furthermore, these data support rational combinations of hypomethylating agents with SMO antagonists in clinical trials.


Asunto(s)
Proteínas Hedgehog/metabolismo , Factores de Transcripción de Tipo Kruppel/fisiología , Leucemia Mieloide Aguda/metabolismo , Proteínas del Tejido Nervioso/fisiología , Proteínas Represoras/fisiología , Receptor Smoothened/antagonistas & inhibidores , Animales , Línea Celular Tumoral , Xenoinjertos , Humanos , Ratones , Proteína Oncogénica v-akt/metabolismo , Proteína Gli3 con Dedos de Zinc
20.
Bioorg Med Chem Lett ; 29(2): 172-178, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30528695

RESUMEN

A series of novel tetrazole analogues of resveratrol were synthesized and evaluated for their anti-leukemic activity against an extensive panel of human cancer cell lines and against the MV4-11 AML cell line. These molecules were designed as drug-like derivatives of the resveratrol analogue DMU-212 and its cyano derivatives. Four compounds 8g, 8h, 10a and 10b exhibited LD50 values of 4.60 µM, 0.02 µM, 1.46 µM, and 1.08 µM, respectively, against MV4-11 leukemia cells. The most potent compounds, 8h and 10b, were also found to be active against an extensive panel of human hematological and solid tumor cell lines; compound 8h was the most potent compound with GI50 values <10 nM against more than 90% of the human cancer cell lines in the 60-cell panel. Analogues 8g, 8h, 10a and 10b were also tested for their ability to inhibit the polymerization of tubulin, and compound 8h was found to be the most potent analogue. Molecular modeling studies demonstrated that 8h binds to the colchicine binding site on tubulin. Thus, compound 8h is considered to be a lead druglike molecule from this tetrazole series of compounds.


Asunto(s)
Antineoplásicos/farmacología , Tetrazoles/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Relación Estructura-Actividad , Tetrazoles/síntesis química , Tetrazoles/química
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