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Leptospirosis is a neglected zoonotic disease that commonly affects cattle, pigs, horses, and dogs in many countries. Infection in dogs is usually subclinical, but acute cases of leptospirosis may occur along with systemic failure, which may become fatal. After recovery from an acute infection, dogs may become asymptomatic carriers and shed pathogenic leptospires through urine for long periods of time. Here, a study of ten different cases of leptospirosis is presented, showing the relevance of dogs as asymptomatic carriers of pathogenic Leptospira. The diagnosis was confirmed via isolation and further serological and genetic identification. Four Leptospira isolates (LOCaS28, 31, 34, and 46) were obtained from the kidneys and urine samples of 58 dogs destined for destruction (6.89%) at a Canine Control Center in Mexico City. No spirochetes were observed in the urine samples of those Leptospira-positive dogs examined under dark-field microscopy, and no clinical signs of disease were observed either. Six additional isolates were obtained: two came from asymptomatic carrier dogs (CEL60 and UADY22); another isolate came from an asymptomatic dog that was a pack companion of a clinically ill dog with fatal leptospirosis (AGFA24); and finally, three isolates were taken from dogs that died of leptospirosis (LOCaS59, Citlalli, and Nayar1). Nine out of the ten isolates were identified as being from the serogroup Canicola via cross-absorption MAT using reference strains and specific antisera, and their identity was genetically confirmed as Canicola ST34 via multi-locus sequencing typing (MLST). In contrast, the isolate Nayar1 was identified as serovar Copenhageni ST2. Interestingly, the asymptomatic dogs from which Leptospira isolates were recovered consistently showed high antibody titers in the microscopic agglutination test (MAT), revealing values of at least 1:3200 against serogroup Canicola and lower titer values against other serogroups. Isolates showed different virulence levels in the hamster model. Taken as a whole, all these findings confirmed that dogs may act as asymptomatic carriers of pathogenic leptospires and possibly spread them out to the environment, thus representing an active public health risk. The results also showed that the Canicola ST34 clone is the most prevalent Leptospira serovar in dogs in Mexico, and finally that the old-fashioned MAT is a good alternative for the detection of presumptive Leptospira asymptomatic carrier dogs.
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Architectural proteins are essential epigenetic regulators that play a critical role in organizing chromatin and controlling gene expression. CTCF (CCCTC-binding factor) is a key architectural protein responsible for maintaining the intricate 3D structure of chromatin. Because of its multivalent properties and plasticity to bind various sequences, CTCF is similar to a Swiss knife for genome organization. Despite the importance of this protein, its mechanisms of action are not fully elucidated. It has been hypothesized that its versatility is achieved through interaction with multiple partners, forming a complex network that regulates chromatin folding within the nucleus. In this review, we delve into CTCF's interactions with other molecules involved in epigenetic processes, particularly histone and DNA demethylases, as well as several long non-coding RNAs (lncRNAs) that are able to recruit CTCF. Our review highlights the importance of CTCF partners to shed light on chromatin regulation and pave the way for future exploration of the mechanisms that enable the finely-tuned role of CTCF as a master regulator of chromatin.
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Cromatina , DNA , Fator de Ligação a CCCTC/genética , DNA/metabolismo , Núcleo Celular/metabolismo , GenomaRESUMO
PURPOSE: Astrocytomas are a type of malignant brain tumor with an unfavorable clinical course. The impact of AGT and MGMT somatic variants in the prognosis of astrocytoma is unknown, and it is controversial for TP53. Moreover, there is a lack of knowledge regarding the molecular characteristics of astrocytomas in Mexican patients. METHODS: We studied 48 Mexican patients, men and women, with astrocytoma (discovery cohort). We performed DNA deep sequencing in tumor samples, targeting AGT, MGMT and TP53, and we studied MGMT gene promoter methylation status. Then we compared our findings to a cohort which included data from patients with astrocytoma from The Cancer Genome Atlas (validation cohort). RESULTS: In the discovery cohort, we found a higher number of somatic variants in AGT and MGMT than in the validation cohort (10.4% vs < 1%, p < 0.001), and, in both cohorts, we observed only women carried variants AGT variants. We also found that the presence of either MGMT variant or promoter methylation was associated to better survival and response to chemotherapy, and, in conjunction with TP53 variants, to progression-free survival. CONCLUSIONS: The occurrence of AGT variants only in women expands our knowledge about the molecular differences in astrocytoma between men and women. The increased prevalence of AGT and MGMT variants in the discovery cohort also points towards possible distinctions in the molecular landscape of astrocytoma among populations. Our findings warrant further study.
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Astrocitoma , Neoplasias Encefálicas , Feminino , Humanos , Masculino , Astrocitoma/patologia , Biomarcadores , Neoplasias Encefálicas/patologia , DNA/uso terapêutico , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Mutação , Prognóstico , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
Long-term studies have shown significantly lower mortality rates in patients with continuous clozapine (CLZ) treatment than other antipsychotics. We aimed to evaluate epigenetic age and DNA methylome differences between CLZ-treated patients and those without psychopharmacological treatment. The DNA methylome was analyzed using the Infinium MethylationEPIC BeadChip in 31 CLZ-treated patients with psychotic disorders and 56 patients with psychiatric disorders naive to psychopharmacological treatment. Delta age (Δage) was calculated as the difference between predicted epigenetic age and chronological age. CLZ-treated patients were stratified by sex, age, and years of treatment. Differential methylation sites between both groups were determined using linear regression models. The Δage in CLZ-treated patients was on average lower compared with drug-naive patients for the three clocks analyzed; however, after data-stratification, this difference remained only in male patients. Additional differences were observed in Hannum and Horvath clocks when comparing chronological age and years of CLZ treatment. We identified 44,716 differentially methylated sites, of which 87.7% were hypomethylated in CLZ-treated patients, and enriched in the longevity pathway genes. Moreover, by protein-protein interaction, AMPK and insulin signaling pathways were found enriched. CLZ could promote a lower Δage in individuals with long-term treatment and modify the DNA methylome of the longevity-regulating pathways genes.
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KDM4 proteins are a subfamily of histone demethylases that target the trimethylation of lysines 9 and 36 of histone H3, which are associated with transcriptional repression and elongation respectively. Their deregulation in cancer may lead to chromatin structure alteration and transcriptional defects that could promote malignancy. Despite that KDM4 proteins are promising drug targets in cancer therapy, only a few drugs have been described as inhibitors of these enzymes, while studies on natural compounds as possible inhibitors are still needed. Natural compounds are a major source of biologically active substances and many are known to target epigenetic processes such as DNA methylation and histone deacetylation, making them a rich source for the discovery of new histone demethylase inhibitors. Here, using transcriptomic analyses we determined that the KDM4 family is deregulated and associated with a poor prognosis in multiple neoplastic tissues. Also, by molecular docking and molecular dynamics approaches, we screened the COCONUT database to search for inhibitors of natural origin compared to FDA-approved drugs and DrugBank databases. We found that molecules from natural products presented the best scores in the FRED docking analysis. Molecules with sugars, aromatic rings, and the presence of OH or O- groups favor the interaction with the active site of KDM4 subfamily proteins. Finally, we integrated a protein-protein interaction network to correlate data from transcriptomic analysis and docking screenings to propose FDA-approved drugs that could be used as multitarget therapies or in combination with the potential natural inhibitors of KDM4 enzymes. This study highlights the relevance of the KDM4 family in cancer and proposes natural compounds that could be used as potential therapies.
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High-grade serous ovarian carcinoma (HGSC) is the most lethal gynecologic malignancy due to the lack of reliable biomarkers, effective treatment, and chemoresistance. Improving the diagnosis and the development of targeted therapies is still needed. The molecular pathomechanisms driving HGSC progression are not fully understood though crucial for effective diagnosis and identification of novel targeted therapy options. The oncogene CTCFL (BORIS), the paralog of CTCF, is a transcriptional factor highly expressed in ovarian cancer (but in rarely any other tissue in females) with cancer-specific characteristics and therapeutic potential. In this work, we seek to understand the regulatory functions of CTCFL to unravel new target genes with clinical relevance. We used in vitro models to evaluate the transcriptional changes due to the presence of CTCFL, followed by a selection of gene candidates using de novo network enrichment analysis. The resulting mechanistic candidates were further assessed regarding their prognostic potential and druggability. We show that CTCFL-driven genes are involved in cytoplasmic membrane functions; in particular, the PI3K-Akt initiators EGFR1 and VEGFA, as well as ITGB3 and ITGB6 are potential drug targets. Finally, we identified the CTCFL targets ACTBL2, MALT1 and PCDH7 as mechanistic biomarkers to predict survival in HGSC. Finally, we elucidated the value of CTCFL in combination with its targets as a prognostic marker profile for HGSC progression and as putative drug targets.
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Proteínas de Ligação a DNA , Neoplasias Ovarianas , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Fatores de TranscriçãoRESUMO
BACKGROUND: The ESR1 gene suffers methylation changes in many types of cancers, including breast cancer (BC), the most frequently diagnosed cancer in women that is also present in men. Methylation at promoter A of ESR1 is the worse prognosis in terms of overall survival; thus, the early detection, prognostic, and prediction of therapy involve some methylation biomarkers. METHODS: Therefore, our study aimed to examine the methylation levels at the ESR1 gene in samples from Mexican BC patients and its possible association with menopausal status. RESULTS: We identified a novel 151-bp CpG island in the promoter A of the ESR1 gene. Interestingly, methylation levels at this CpG island in positive ERα tumors were approximately 50% less than negative ERα or control samples. Furthermore, methylation levels at ESR1 were associated with menopausal status. In postmenopausal patients, the methylation levels were 1.5-fold higher than in premenopausal patients. Finally, according to tumor malignancy, triple-negative cancer subtypes had higher ESR1 methylation levels than luminal/HER2+ or luminal A subtypes. CONCLUSIONS: Our findings suggest that methylation at this novel CpG island might be a promising prognosis marker.
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Chromatin architecture influences transcription by modulating the physical access of regulatory factors to DNA, playing fundamental roles in cell identity. Studies on dopaminergic differentiation have identified coding genes, but the relationship with non-coding genes or chromatin accessibility remains elusive. Using RNA-Seq and ATAC-Seq we profiled differentially expressed transcripts and open chromatin regions during early dopaminergic neuron differentiation. Hierarchical clustering of differentially expressed genes, resulted in 6 groups with unique characteristics. Surprisingly, the abundance of long non-coding RNAs (lncRNAs) was high in the most downregulated transcripts, and depicted positive correlations with target mRNAs. We observed that open chromatin regions decrease upon differentiation. Enrichment analyses of accessibility depict an association between open chromatin regions and specific functional pathways and gene-sets. A bioinformatic search for motifs allowed us to identify transcription factors and structural nuclear proteins that potentially regulate dopaminergic differentiation. Interestingly, we also found changes in protein and mRNA abundance of the CCCTC-binding factor, CTCF, which participates in genome organization and gene expression. Furthermore, assays demonstrated co-localization of CTCF with Polycomb-repressed chromatin marked by H3K27me3 in pluripotent cells, progressively decreasing in neural precursor cells and differentiated neurons. Our work provides a unique resource of transcription factors and regulatory elements, potentially involved in the acquisition of human dopaminergic neuron cell identity.
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Diferenciação Celular/genética , Cromatina/metabolismo , Neurônios Dopaminérgicos/citologia , Células-Tronco Embrionárias Humanas/citologia , Transcriptoma/genética , Fator de Ligação a CCCTC/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Motivos de Nucleotídeos/genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA-Seq , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
COVID-19 is an infection caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome coronavirus 2), which has caused a global outbreak. Current research efforts are focused on the understanding of the molecular mechanisms involved in SARS-CoV-2 infection in order to propose drug-based therapeutic options. Transcriptional changes due to epigenetic regulation are key host cell responses to viral infection and have been studied in SARS-CoV and MERS-CoV; however, such changes are not fully described for SARS-CoV-2. In this study, we analyzed multiple transcriptomes obtained from cell lines infected with MERS-CoV, SARS-CoV, and SARS-CoV-2, and from COVID-19 patient-derived samples. Using integrative analyses of gene co-expression networks and de-novo pathway enrichment, we characterize different gene modules and protein pathways enriched with Transcription Factors or Epifactors relevant for SARS-CoV-2 infection. We identified EP300, MOV10, RELA, and TRIM25 as top candidates, and more than 60 additional proteins involved in the epigenetic response during viral infection that has therapeutic potential. Our results show that targeting the epigenetic machinery could be a feasible alternative to treat COVID-19.
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COVID-19/genética , Epigênese Genética/genética , SARS-CoV-2/genética , Transcriptoma/genética , COVID-19/virologia , Perfilação da Expressão Gênica , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , SARS-CoV-2/patogenicidade , Transdução de Sinais/genéticaRESUMO
The axolotl (Ambystoma mexicanum) has been a widely studied organism due to its capacity to regenerate most of its cells, tissues and whole-body parts. Since its genome was sequenced, several molecular tools have been developed to study the mechanisms behind this outstanding and extraordinary ability. The complexity of its genome due to its sheer size and the disproportionate expansion of a large number of repetitive elements, may be a key factor at play during tissue remodeling and regeneration mechanisms. Transcriptomic analysis has provided information to identify candidate genes networks and pathways that might define successful or failed tissue regeneration. Nevertheless, the epigenetic machinery that may participate in this phenomenon has largely not been studied. In this review, we outline a broad overview of both genetic and epigenetic molecular processes related to regeneration in axolotl, from the macroscopic to the molecular level. We also explore the epigenetic mechanisms behind regenerative pathways, and its potential importance in future regeneration research. Altogether, understanding the genomics and global regulation in axolotl will be key for elucidating the special biology of this organism and the fantastic phenomenon that is regeneration.
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Ambystoma mexicanum , Epigenômica , Regeneração/genética , Ambystoma mexicanum/genética , Ambystoma mexicanum/crescimento & desenvolvimento , Animais , Extremidades , Perfilação da Expressão Gênica , Genoma , GenômicaRESUMO
Clozapine (CLZ) is the only antipsychotic drug that has been proven to be effective in patients with refractory psychosis, but it has also been proposed as an effective mood stabilizer; however, the complex mechanisms of action of CLZ are not yet fully known. To find predictors of CLZ-associated phenotypes (i.e., the metabolic ratio, dosage, and response), we explore the genomic and epigenomic characteristics of 44 patients with refractory psychosis who receive CLZ treatment based on the integration of polygenic risk score (PRS) analyses in simultaneous methylome profiles. Surprisingly, the PRS for bipolar disorder (BD-PRS) was associated with the CLZ metabolic ratio (pseudo-R2 = 0.2080, adjusted p-value = 0.0189). To better explain our findings in a biological context, we assess the protein-protein interactions between gene products with high impact variants in the top enriched pathways and those exhibiting differentially methylated sites. The GABAergic synapse pathway was found to be enriched in BD-PRS and was associated with the CLZ metabolic ratio. Such interplay supports the use of CLZ as a mood stabilizer and not just as an antipsychotic. Future studies with larger sample sizes should be pursued to confirm the findings of this study.
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Introducción: la hiperplasia suprarrenal congénita (HSC) es el desorden adrenal más común en la infancia y la causa más frecuente de ambigüedad sexual. La forma clásica, que representa los casos más severos de este déficit, se asocia en un 75 % con pérdida de sal. Por otra parte, en los recién nacidos (RN) del sexo femenino se pueden presentar grados severos de virilización de genitales. Objetivo: presentar los resultados (durante diez años), del Programa Cubano de Pesquisa Neonatal (PN) de la HSC, soportado en un procedimiento inmunoenzimático desarrollado en Cuba. Resultados: en el período de enero 2005 a diciembre 2014, se han estudiado 1 140 882 RN y se detectaron 56 niños con HSC, para una incidencia de 1:20 373 RN. La cobertura del programa se ha incrementado hasta llegar en el año 2013 al 99.34 % de todos los RN cubanos. Conclusiones: la existencia del Programa Cubano de PN de HSC, ha permitido estimar la incidencia e incrementar el conocimiento de esta enfermedad. La PN ha posibilitado el diagnóstico precoz en la variedad perdedora de sal, contribuyendo a la disminución de la mortalidad infantil. El Programa ha favorecido a pacientes con formas virilizantes de la enfermedad, mediante la asignación correcta del sexo
Introduction: Congenital Adrenal Hyperplasia (HSC) is the most common adrenal disorder in childhood and the most frequent cause of sexual ambiguity. The classic form, which represents the most severe causes of this deficit, is associated in 75 % with loss of salt. On the other hand, in the NB of the female sex that present severe degrees of virilization of the genitals. Objective: To present result of the application for ten years of the Cuban Neonatal Research Program of the HSC, supported by an inmmunoenzymatic procedure developed in Cuba. Result: In the period from January 2005 to December 2014, using the UMELISA 17 OH PROGESTERONA NEONATAL, 1 140882 RN were detected, for an incidence of 1:20373 RN. The coverage of the program has been increasing until2013 reaching 99.34 % of all Cuban RN. Conclusion: The existence of the Cuban HSC PN Program, has allowed estimating the incidence and increase knowledge of this disease in our country. PN has made possible the early diagnosis of patients with the salt losing variety, contributing to decrease in infant mortality nationwide. The Program has favored patients with virilizing form of the disease, through the correct assignment of sex
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Humanos , Masculino , Feminino , Recém-Nascido , Hiperplasia Suprarrenal Congênita , Recém-Nascido , Programas Nacionais de SaúdeRESUMO
Astrocytoma is the most common type of primary brain tumor. The risk factors for astrocytoma are poorly understood; however, germline genetic variants account for 25% of the risk of developing gliomas. In this study, we assessed the risk of astrocytoma associated with variants in AGT, known by its role in angiogenesis, TP53, a well-known tumor suppressor and the DNA repair gene MGMT in a Mexican population. A case-control study was performed in 49 adult Mexican patients with grade II-IV astrocytoma. Sequencing of exons and untranslated regions of AGT, MGMT, and TP53 from was carried in an Ion Torrent platform. Individuals with Mexican Ancestry from the 1000 Genomes Project were used as controls. Variants found in our cohort were then assessed in a The Cancer Genome Atlas astrocytoma pan-ethnic validation cohort. Variants rs1926723 located in AGT (OR 2.74, 1.40-5.36 95% CI), rs7896488 in MGMT (OR 3.43, 1.17-10.10 95% CI), and rs4968187 in TP53 (OR 2.48, 1.26-4.88 95% CI) were significantly associated with the risk of astrocytoma after multiple-testing correction. This is the first study where the AGT rs1926723 variant, TP53 rs4968187, and MGMT rs7896488 were found to be associated with the risk of developing an astrocytoma.
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Angiotensinogênio/genética , Astrocitoma/genética , Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Variação Genética/genética , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Adulto , Astrocitoma/epidemiologia , Astrocitoma/patologia , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-IdadeRESUMO
The wide variety of pathogenic Leptospira serovars and the weak protection offered by the available vaccines encourage the search for protective immunogens against leptospirosis. We found that the secretin GspD of the type II secretion system (T2S) of Leptospira interrogans serovar Canicola was highly conserved amongst pathogenic serovars and was expressed in vivo during infection, as shown by immunohistochemistry. Convalescent sera of hamsters, dogs, and cows showed the presence of IgG antibodies, recognizing a recombinant version of this protein expressed in Escherichia coli (rGspDLC) in Western blot assays. In a pilot vaccination study, a group of eight hamsters was immunized on days zero and 14 with 50 µg of rGspDLC mixed with Freund's incomplete adjuvant (FIA). On day 28 of the study, 1,000 LD50 (Lethal Dose 50%) of a virulent strain of Leptospira interrogans serovar Canicola (LOCaS46) were inoculated by an intraoral submucosal route (IOSM). Seventy-five percent protection against disease (p = 0.017573, Fisher's exact test) and 50% protection against infection were observed in this group of vaccinated hamsters. In contrast, 85% of non-vaccinated hamsters died six to nine days after the challenge. These results suggest the potential usefulness of the T2S secretin GspD of Leptospira as a protective recombinant vaccine against leptospirosis.
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La hipoacusia tiene una incidencia notable entre los recién nacidos. Una intervención temprana durante el período de maduración auditiva permite minimizar los efectos en el desarrollo intelectual del infante. Se propone el desarrollo de un Registrador de Emisiones Otoacústicas Transientes como parte de un sistema de cribado neonatal basado en microcontroladores de alto rendimiento. La prueba consiste en aplicar periódicamente un estímulo tipo chasquido para obtener la respuesta coclear. Se promedian las señales adquiridas y se aplica la Transformada Rápida de Fourier. El espectro obtenido es dividido en bandas de media octava para analizar la correlación y la relación señal-ruido. Si estos parámetros son mayores que los umbrales de referencia en la mayoría de las bandas, se considera al paciente apto para el desarrollo normal. El firmware fue implementado sobre el procesador STM32F405 y evaluado con el simulador Baby Isao; obteniéndose una sensibilidad del 87.5 por ciento y una especificidad del 93.75 por ciento(AU)
Hearing loss is highly incident among newborns. Early intervention during the period of auditory maturation allows adequate levels of intellectual development to be achieved. The development of a Transient Otoacoustic Emissions Recorder is proposed as part of a neonatal screening system based on high-performance microcontrollers. The test consists of periodically applying a click stimulus to obtain the cochlear response. The acquired signals are averaged and the Fast Fourier Transform is applied. The spectrum obtained is divided into half-octave bands to assess the correlation as well as the signal-noise ratio. If these parameters are greater than the reference thresholds in most of the bands, the patient is considered suitable for normal cognitive development. The firmware was implemented on the STM32F405 processor and evaluated with the Baby Isao simulator; obtaining a sensitivity of 87.5 percent and a specificity of 93.75 percent(AU)
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Humanos , Masculino , Feminino , Lactente , Triagem Neonatal , Emissões Otoacústicas Espontâneas , Análise de Fourier , Perda Auditiva/epidemiologiaRESUMO
Outdoor particulate matter (PM10) exposure is carcinogenic to humans. The cellular mechanism by which PM10 is associated specifically with lung cancer includes oxidative stress and damage to proteins, lipids, and DNA in the absence of apoptosis, suggesting that PM10 induces cellular survival. We aimed to evaluate the PI3K/AKT/FoxO3a pathway as a mechanism of cell survival in lung epithelial A549 cells exposed to PM10 that were subsequently challenged with hydrogen peroxide (H2O2). Our results showed that pre-exposure to PM10 followed by H2O2, as a second oxidant stimulus increased the phosphorylation rate of pAKTSer473, pAKTThr308, and pFoxO3aSer253 2.5-fold, 1.8-fold, and 1.2-fold, respectively. Levels of catalase and p27kip1, which are targets of the PIK3/AKT/FoxO3a pathway, decreased 38.1% and 62.7%, respectively. None of these changes had an influence on apoptosis; however, the inhibition of PI3K using the LY294002 compound revealed that the PI3K/AKT/FoxO3a pathway was involved in apoptosis evasion. We conclude that nontoxic PM10 exposure predisposes lung epithelial cell cultures to evade apoptosis through the PI3K/AKT/FoxO3a pathway when cells are treated with a second oxidant stimulus.
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Células Epiteliais Alveolares/efeitos dos fármacos , Apoptose , Estresse Oxidativo , Material Particulado/farmacologia , Transdução de Sinais , Células A549 , Células Epiteliais Alveolares/metabolismo , Proteína Forkhead Box O3/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Angiogenesis is a crucial process for organ morphogenesis and growth during development, and it is especially relevant during the repair of wounded tissue in adults. It is coordinated by an equilibrium of pro- and anti-angiogenic factors; nevertheless, when affected, it promotes several diseases. Lately, a growing body of evidence is indicating that non-coding RNAs (ncRNAs), such as miRNAs, circRNAs, and lncRNAs, play critical roles in angiogenesis. These ncRNAs can act in cis or trans and alter gene transcription by several mechanisms including epigenetic processes. In the following pages, we will discuss the functions of ncRNAs in the regulation of angiogenesis and neovascularization, both in normal and disease contexts, from an epigenetic perspective. Additionally, we will describe the contribution of Next-Generation Sequencing (NGS) techniques to the discovery and understanding of the role of ncRNAs in angiogenesis.
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The identification of prognostic biomarkers is a priority for patients suffering from high-grade serous ovarian cancer (SOC), which accounts for >70% of ovarian cancer (OC) deaths. Meanwhile, borderline ovarian cancer (BOC) is a low malignancy tumor and usually patients undergo surgery with low probabilities of recurrence. However, SOC remains the most lethal neoplasm due to the lack of biomarkers for early diagnosis and prognosis. In this regard, BORIS (CTCFL), a CTCF paralog, is a promising cancer biomarker that is overexpressed and controls transcription in several cancer types, mainly in OC. Studies suggest that BORIS has an important function in OC by altering gene expression, but the effect and extent to which BORIS influences transcription in OC from a genome-wide perspective is unclear. Here, we sought to identify BORIS target genes in an OC cell line (OVCAR3) with potential biomarker use in OC tumor samples. To achieve this, we performed in vitro knockout and knockdown experiments of BORIS in OVCAR3 cell line followed by expression microarrays and bioinformatics network enrichment analysis to identify relevant BORIS target genes. In addition, ex vivo expression data analysis of 373 ovarian cancer patients were evaluated to identify the expression patterns of BORIS target genes. In vitro, we uncovered 130 differentially expressed genes and obtained the BORIS-associated regulatory network, in which the androgen receptor (AR) acts as a major transcription factor. Also, FN1, FAM129A, and CD97 genes, which are related to chemoresistance and metastases in OC, were identified. In SOC patients, we observed that malignancy is associated with high levels of BORIS expression while BOC patients show lower levels. Our study suggests that BORIS acts as a main regulator, and has the potential to be used as a prognostic biomarker and to yield novel drug targets among the genes BORIS controls in SOC patients.
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During midbrain development, dopamine neuron differentiation occurs before birth. Epigenetic processes such as DNA methylation and demethylation as well as post-translational modification of histones occur during neurogenesis. Here, we administered histamine (HA) into the brain of E12 embryos in vivo and observed significant lower immunoreactivity of Lmx1a+ and Tyrosine Hydroxylase (TH)+ cells, with parallel decreases in the expression of early (Lmx1a, Msx1) and late (Th) midbrain dopaminergic (mDA) genes. With MeDIP assays we found that HA decreases the percentage of 5-methylcytosine of Pitx3 and Th, without changes in 5-hydroxymethylcytosine. Additionally, HA treatment caused a significant increase in the repressive epigenetic modifications H3K9me3 in Pitx3 and Th, and also more H3K27me3 marks in Th. Furthermore, HA has a long-term effect on the formation of the nigrostriatal and mesolimbic/mesocortical pathways, since it causes a significant decrease in midbrain TH immunoreactivity, as well as alterations in dopaminergic neuronal fibers, and significant lower TH-positive area in the forebrain in whole-mount stainings. These findings suggest that HA diminishes dopaminergic gene transcription by altering several epigenetic components related to DNA and histone modifications, which affects mDA neuron progression during development.
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Introducción: La estimación de la audición con Potenciales Evocados Auditivos de Tallo Cerebral obtenidos mediante estímulos tipo chirp constituye una alternativa de reciente aplicación. Varios autores han demostrado que, este tipo de estimulación compensa el retardo de la onda sonora en la codificación de frecuencias, generándose Potenciales Evocados Auditivos de Tallo Cerebral con componentes de amplitudes mayores. Objetivos: Diseñar y generar un estímulo chirp (banda ancha) para implementar en el sistema AUDIX (La Habana, Neuronic SA) y, realizar una serie de controles para evaluar su viabilidad en el registro de Potenciales Evocados Auditivos de Tallo Cerebral en sujetos con audición normal. Métodos: Las formulaciones que se utilizaron en la generación del estímulo fueron implementadas como una función en Matlab®, y luego, insertada en el sistema AUDIX con las siguientes especificaciones técnicas, frecuencia de muestreo: 48 kHz, composición de frecuencias (ascendente): 350-11300 Hz, y duración total: 4,95 ms. Se obtuvieron registros de PEATC mediante estímulos chirp y click a un nivel de intensidad fija (60 dB nHL) en 9 sujetos adultos (18 oídos) con audición normal. Resultados: El estímulo chirp diseñado tuvo un comportamiento funcional similar a lo reportado en la literatura. Cuando se compara con los Potenciales Evocados Auditivos de Tallo Cerebral -click, la onda V de Potenciales Evocados Auditivos de Tallo Cerebral -chirp mostró valores de amplitud significativamente mayores (relación de amplitud chirp/click: 1,62), con una ganancia promedio de 54 por ciento (p< 0,001, n= 18, prueba de rangos de Wilcoxon). Conclusiones: El estímulo chirp (banda ancha) diseñado resulta más eficiente que el estímulo click para obtener registros de Potenciales Evocados Auditivos de Tallo Cerebral. Con respecto a la amplitud de la onda V, el sistema muestra un funcionamiento lineal (mejor sincronía neural). Este tipo de estimulación pudiera resultar de mucha utilidad en programas de pesquisa auditiva neonatal pues la obtención de una onda V de mayor amplitud permitiría su fácil y rápida detección, y posible automatización(AU)
Introduction: Estimation of audition through brainstem auditory evoked potentials obtained by chirp stimuli is an alternative of recent application. It has been shown by several authors that this type of stimulation compensates for retardation of the sound wave in the coding of frequencies, generating auditory evoked responses with components of higher amplitudes. Objectives: Design and develop a broad-band chirp stimulus to be implemented in the AUDIX system and conduct a control series evaluation of its viability to register brainstem auditory evoked potentials in normal-hearing subjects. Methods: The formulations used to generate the stimulus were implemented as a function on Matlab® and then incorporated into the AUDIX system with the following technical specifications: sampling frequency: 48 kHz, frequency composition (rising): 350-11 300 Hz, and total duration: 4.95 ms. BAEP registries were obtained with chirp and click stimuli at a fixed intensity level (60 dB nHL) in nine normal-hearing adult subjects (18 ears). Results: The chirp stimulus designed had a functional behavior similar to the one reported in the literature. When compared with the click-BAEP, the V wave of chirp-BAEP displayed significantly higher amplitude values (chirp/click amplitude ratio: 1.62), with an average gain of 54 percent (p< 0.001, n= 18, Wilcoxon rank test). Conclusions: The broad band chirp stimulus designed proved to be more efficient than the click stimulus to obtain registries of Brainstem Auditory Evoked Potentials. Regarding V wave amplitude, the system was found to function linearly (better neural synchrony). This type of stimulation could be very useful in neonatal hearing screening programs, since a higher amplitude V wave could facilitate its fast and easy detection and possible automation(AU)