RESUMEN

The complement system and neutrophils play crucial roles in innate immunity. Neutrophils release neutrophil extracellular traps (NETs), which are composed of decondensed DNA entangled with granular contents, as part of their innate immune function. Mechanisms governing complement-mediated NET formation remain unclear. In this study, we tested a two-step NETosis mechanism, as follows: classical complement-mediated neutrophil activation in serum and subsequent NET formation in serum-free conditions, using neutrophils from healthy donors, endothelial cells, and various assays (Fluo-4AM, DHR123, and SYTOX), along with flow cytometry and confocal microscopy. Our findings reveal that classical complement activation on neutrophils upregulated the membrane-anchored complement regulators CD46, CD55, and CD59. Additionally, complement activation increased CD11b on neutrophils, signifying activation and promoting their attachment to endothelial cells. Complement activation induced calcium influx and citrullination of histone 3 (CitH3) in neutrophils. However, CitH3 formation alone was insufficient for NET generation. Importantly, NET formation occurred only when neutrophils were in serum-free conditions. In such environments, neutrophils induced NADPH oxidase-dependent reactive oxygen species (ROS) production, leading to NET formation. Hence, we propose that complement-mediated NET formation involves a two-step process, as follows: complement deposition, neutrophil priming, calcium influx, CitH3 formation, and attachment to endothelial cells in serum. This is followed by NADPH-dependent ROS production and NET completion in serum-free conditions. Understanding this process may unveil treatment targets for pathologies involving complement activation and NET formation.

Asunto(s)

Calcio , Activación de Complemento , Trampas Extracelulares , NADPH Oxidasas , Activación Neutrófila , Neutrófilos , Especies Reactivas de Oxígeno , Trampas Extracelulares/metabolismo , Humanos , Neutrófilos/metabolismo , Neutrófilos/inmunología , NADPH Oxidasas/metabolismo , Calcio/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas del Sistema Complemento/metabolismo , Células Endoteliales/metabolismo , Medio de Cultivo Libre de Suero/farmacología , Histonas/metabolismo

RESUMEN

In end-stage heart failure, which is characterized by persistent or progressive ventricular dysfunction despite optimal medical therapy, a left ventricular assist device (LVAD) can be beneficial. Congestive heart failure provokes inflammatory and prothrombotic activation. The aim of this study was to evaluate the serum concentration of citrullinated histone 3 (CH3) representing neutrophil extracellular trap (NET) formation in patients referred for LVAD implantation. There were 10 patients with a median age of 61 (57-65) years enrolled in a prospective single-center analysis who underwent LVAD implantation. The CH3 plasma concentration was measured preoperatively and on the 1st and 7th postoperative days, followed by control measurements on the median (Q1-3) 88th (49-143) day. The preoperative CH3 concentration strongly correlated with brain natriuretic peptide (r = 0.879, p < 0.001). Significant differences in CH3 serum concentration were observed between pre- and postoperative measurements, including an increase on the first postoperative day (p < 0.001), as well as a decrease on the seventh day (p = 0.016) and in follow-up (p < 0.001). CH3 concentration, as a marker of NET formation, decreases after LVAD implantation.

Asunto(s)

Trampas Extracelulares , Insuficiencia Cardíaca , Corazón Auxiliar , Histonas , Humanos , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/terapia , Trampas Extracelulares/metabolismo , Persona de Mediana Edad , Masculino , Femenino , Anciano , Histonas/sangre , Histonas/metabolismo , Estudios Prospectivos , Biomarcadores/sangre , Neutrófilos/metabolismo , Citrulinación

RESUMEN

Paediatric high-grade gliomas are among the most common malignancies found in children. Despite morphological similarities to their adult counterparts, there are profound biological and molecular differences. Furthermore, and thanks to molecular biology, the diagnostic pathology of paediatric high-grade gliomas has experimented a dramatic shift towards molecular classification, with important prognostic implications, as is appropriately reflected in both the current WHO Classification of Tumours of the Central Nervous System and the WHO Classification of Paediatric Tumours. Emphasis is placed on histone 3, IDH1, and IDH2 alterations, and on Receptor of Tyrosine Kinase fusions. In this review we present the current diagnostic categories from the diagnostic pathology perspective including molecular features.

Asunto(s)

Neoplasias Encefálicas , Glioma , Humanos , Glioma/genética , Glioma/patología , Glioma/clasificación , Glioma/metabolismo , Niño , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/clasificación , Clasificación del Tumor , Isocitrato Deshidrogenasa/genética , Histonas/metabolismo , Histonas/genética , Biomarcadores de Tumor/genética , Pronóstico

RESUMEN

Previously, we reported the efficacy and safety of tazemetostat in Japanese patients with relapsed/refractory follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) harboring the EZH2 mutation in a multicenter, open-label, phase II study. Here, we present a follow-up analysis of tazemetostat at a long-term median follow-up of 35.0 months. Twenty patients were enrolled: 17 in the FL cohort and three in the DLBCL cohort. In the FL cohort, the objective response rate was 70.6%, consistent with the primary analysis, and the median progression-free survival (PFS) was not reached. The 24-month and 36-month PFS rates were 72.1% (95% confidence interval [CI] 41.5%-88.6%) and 64.1% (95% CI 33.7%-83.4%), respectively. The median duration of treatment was 30.2 months. After the primary analysis at a median follow-up of 12.9 months, grade 1-2 urinary tract infection, peripheral motor neuropathy, and hypogammaglobulinemia newly emerged, but the incidence of adverse events (AEs) did not increase notably during this follow-up period. No unexpected grade ≥ 3 treatment-related AEs were reported. Long-term oral monotherapy with tazemetostat showed favorable efficacy and safety profiles, indicating that it may be a useful third-line or later treatment option for patients with relapsed/refractory FL harboring the EZH2 mutation. Trial registration: ClinicalTrials.gov: NCT03456726.

RESUMEN

Haploid induction (HI) holds great promise in expediting the breeding process in onion, a biennial cross-pollinated crop. We used the CENH3-based genome elimination technique in producing a HI line in onion. Here, we downregulated AcCENH3 using the RNAi approach without complementation in five independent lines. Out of five events, only three could produce seeds upon selfing. The progenies showed poor seed set and segregation distortion, and we were unable to recover homozygous knockdown lines. The knockdown lines showed a decrease in accumulation of AcCENH3 transcript and protein in leaf tissue. The decrease in protein content in transgenic plants was correlated with poor seed set. When the heterozygous knockdown lines were crossed with wild-type plants, progenies showed HI by genome elimination of the parental chromosomes from AcCENH3 knockdown lines. The HI efficiency observed was between 0 and 4.63% in the three events, and it was the highest (4.63%) when E1 line was crossed with wildtype. Given the importance of doubled haploids in breeding programmes, the findings from our study are poised to significantly impact onion breeding.

Asunto(s)

Regulación de la Expresión Génica de las Plantas , Haploidia , Cebollas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Interferencia de ARN , Cebollas/genética , Cebollas/metabolismo , Plantas Modificadas Genéticamente/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación hacia Abajo , Fitomejoramiento/métodos , Técnicas de Silenciamiento del Gen

RESUMEN

Loss of perfusion in the burn wound might cause wound deepening and impaired healing. We previously showed persistent microvascular thrombosis coinciding with intraluminal neutrophils extracellular traps in human burned skin. This study investigates the presence of intraluminal citrullinated histone 3 (H3cit) from different cellular origins (neutrophils, monocytes, and lymphocytes) in relation to microvascular thrombosis of burn wounds. Eschar was obtained from burn patients (n = 18) 6-40 days postburn with a mean total burned body surface area of 23%. Microvascular presence of tissue factor (TF), factor XII (FXII) and thrombi was assessed by immunohistochemistry. Intramicrovascular cell death was analyzed via immunofluorescent microscopy, combining antibodies for neutrophils (MPO), monocytes (CD14), and lymphocytes (CD45) with endothelial cell markers CD31 and H3cit. Significantly increased microvascular expression of TF, FXII, and thrombi (CD31+) was found in all eschar samples compared with control uninjured skin. Release of H3cit from different cellular origins was observed in the lumen of the dermal microvasculature in the eschar tissue 7-40 days postburn, with release from neutrophilic origin being 2.7 times more abundant. Intraluminal presence of extracellular H3cit colocalizing with either MPO, CD14, or CD45 is correlated to increased microvascular thrombosis in eschar of burn patients.

Asunto(s)

Quemaduras , Citrulinación , Histonas , Neutrófilos , Trombosis , Humanos , Quemaduras/inmunología , Quemaduras/metabolismo , Quemaduras/complicaciones , Histonas/metabolismo , Histonas/inmunología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Masculino , Femenino , Adulto , Persona de Mediana Edad , Trombosis/metabolismo , Trombosis/inmunología , Trombosis/patología , Tromboplastina/metabolismo , Anciano , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Factor XII/metabolismo , Microvasos/patología , Microvasos/inmunología , Microvasos/metabolismo , Monocitos/inmunología , Monocitos/metabolismo , Piel/patología , Piel/inmunología , Piel/metabolismo , Piel/irrigación sanguínea , Linfocitos/inmunología , Linfocitos/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Trampas Extracelulares/inmunología , Trampas Extracelulares/metabolismo , Adulto Joven

RESUMEN

DNA damage is associated with hyperhomocysteinemia (HHcy) and neural tube defects (NTDs). Additionally, HHcy is a risk factor for NTDs. Therefore, this study examined whether DNA damage is involved in HHcy-induced NTDs and investigated the underlying pathological mechanisms involved. Embryonic day 9 (E9) mouse neuroectoderm cells (NE4C) and homocysteine-thiolactone (HTL, active metabolite of Hcy)-induced NTD chicken embryos were studied by Western blotting, immunofluorescence. RNA interference or gene overexpression techniques were employed to investigate the impact of Menin expression changes on the DNA damage. Chromatin immunoprecipitation-quantitative polymerase chain reaction was used to investigate the epigenetic regulation of histone modifications. An increase in γH2AX (a DNA damage indicator) was detected in HTL-induced NTD chicken embryos and HTL-treated NE4C, accompanied by dysregulation of phospho-Atr-Chk1-nucleotide excision repair (NER) pathway. Further investigation, based on previous research, revealed that disruption of NER was subject to the epigenetic regulation of low-expressed Menin-H3K4me3. Overexpression of Menin or supplementation with folic acid in HTL-treated NE4C reversed the adverse effects caused by high HTL. Additionally, by overexpressing the Mars gene, we tentatively propose a mechanism whereby HTL regulates Menin expression through H3K79hcy, which subsequently influences H3K4me3 modifications, reflecting an interaction between histone modifications. Finally, in 10 human fetal NTDs with HHcy, we detected a decrease in the expression of Menin-H3K4me3 and disorder in the NER pathway, which to some extent validated our proposed mechanism. The present study demonstrated that the decreased expression of Menin in high HTL downregulated H3K4me3 modifications, further weakening the Atr-Chk1-NER pathway, resulting in the occurrence of NTDs.

Asunto(s)

Daño del ADN , Histonas , Homocisteína , Defectos del Tubo Neural , Proteínas Proto-Oncogénicas , Animales , Defectos del Tubo Neural/genética , Defectos del Tubo Neural/metabolismo , Embrión de Pollo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Homocisteína/análogos & derivados , Ratones , Histonas/metabolismo , Epigénesis Genética/efectos de los fármacos , Reparación del ADN/efectos de los fármacos

RESUMEN

We reported the anti-cervical cancer effect of proprietary saponin content from seeds of Impatiens balsamina L., Hosenkoside A. Our study found that Hosenkoside A significantly promotes cell apoptosis and cell cycle arrest after administration, exhibiting anti-tumor effects. Then the transcriptome sequencing results after administration showed that Hosenkoside A had a significant inhibitory effect on Histone deacetylase 3 (HDAC3). After sufficient administration time, the inhibition of HDAC3 expression level leads to a significant decrease in lysine acetylation at histone 3 sites 4 and 9, blocking the activation of Signal transducer and activator of transcription 3 (STAT3) and achieving anti-tumor effects. In addition, we encapsulated Hosenkoside A into polypeptide metal complexes (PMC) to form slow-release spheres. This material breaks down in the tumor environment, not only does it solve the problem of low drug solubility, but it also achieves targeted sustained-release drug delivery. Under the same concentration of stimulation, the PMC complex group showed better anti-tumor effects in both in vitro and in vivo experiments.

Asunto(s)

Complejos de Coordinación , Neoplasias del Cuello Uterino , Femenino , Humanos , Complejos de Coordinación/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Histonas/metabolismo , Puntos de Control del Ciclo Celular , Péptidos/farmacología , Péptidos/metabolismo , Acetilación , Apoptosis , Línea Celular Tumoral

RESUMEN

BACKGROUND: Immunohistochemistry (IHC) is an essential technique in surgical and clinical pathology for detecting diagnostic, prognostic, and predictive biomarkers for personalized cancer therapy. However, the lack of standardization and reference controls results in poor reproducibility, and a reliable tool for IHC quantification is urgently required. The objective of this study was to describe a novel approach in which H3F3B (histone H3, family 3B) can be used as an internal reference standard to quantify protein expression levels using IHC. METHODS: The authors enrolled 89 patients who had human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). They used a novel IHC-based assay to measure protein expression using H3F3B as the internal reference standard. H3F3B was uniformly expressed at the protein level in all tumor regions in cancer tissues. HER2 expression levels were measured with the H-score using HALO software. RESULTS: Kaplan-Meier analysis indicated that, among patients who had HER2-positive BC in The Cancer Genome Atlas data set and the authors' data set, the subgroup with low HER2 expression had a significantly better prognosis than the subgroup with high HER2 expression. Furthermore, the authors observed that HER2 expression levels were precisely evaluated using the proposed method, which can classify patients who are at higher risk of HER2-positive BC to receive trastuzumab-based adjuvant therapy. Dual-color IHC with H3F3B is an excellent tool for internal and external quality control of HER2 expression assays. CONCLUSIONS: The proposed IHC-based quantification method accurately assesses HER2 expression levels and provides insights for predicting clinical prognosis in patients with HER2-positive BC who receive trastuzumab-based adjuvant therapy.

Asunto(s)

Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Histonas , Inmunohistoquímica , Reproducibilidad de los Resultados , Receptor ErbB-2/genética , Trastuzumab/uso terapéutico , Estándares de Referencia , Biomarcadores de Tumor/metabolismo

Asunto(s)

Trampas Extracelulares , Neoplasias , Humanos , Neutrófilos , Histonas , Neoplasias/terapia , Inmunoterapia

RESUMEN

The alternative splicing of PML precursor mRNA gives rise to various PML isoforms, yet their expression profile in breast cancer cells remains uncharted. We discovered that PML1 is the most abundant isoform in all breast cancer subtypes, and its expression is associated with unfavorable prognosis in estrogen receptor-positive (ER+) breast cancers. PML depletion reduces cell proliferation, invasion, and stemness, while heterologous PML1 expression augments these processes and fuels tumor growth and resistance to fulvestrant, an FDA-approved drug for ER + breast cancer, in a mouse model. Moreover, PML1, rather than the well-known tumor suppressor isoform PML4, rescues the proliferation of PML knockdown cells. ChIP-seq analysis reveals significant overlap between PML-, ER-, and Myc-bound promoters, suggesting their coordinated regulation of target gene expression, including genes involved in breast cancer stem cells (BCSCs), such as JAG1, KLF4, YAP1, SNAI1, and MYC. Loss of PML reduces BCSC-related gene expression, and exogenous PML1 expression elevates their expression. Consistently, PML1 restores the association of PML with these promoters in PML-depleted cells. We identified a novel association between PML1 and WDR5, a key component of H3K4 methyltransferase (HMTs) complexes that catalyze H3K4me1 and H3K4me3. ChIP-seq analyses showed that the loss of PML1 reduces H3K4me3 in numerous loci, including BCSC-associated gene promoters. Additionally, PML1, not PML4, re-establishes the H3K4me3 mark on these promoters in PML-depleted cells. Significantly, PML1 is essential for recruiting WDR5, MLL1, and MLL2 to these gene promoters. Inactivating WDR5 by knockdown or inhibitors phenocopies the effects of PML1 loss, reducing BCSC-related gene expression and tumorsphere formation and enhancing fulvestrant's anticancer activity. Our findings challenge the conventional understanding of PML as a tumor suppressor, redefine its role as a promoter of tumor growth in breast cancer and offer new insights into the unique roles of PML isoforms in breast cancer.

RESUMEN

Object: Diffuse midline glioma (DMG) is a highly aggressive and lethal brain tumor predominantly affecting children and young adults. Previously known as diffuse intrinsic pontine glioma (DIPG) or grade IV brain stem glioma, DMG has recently been reclassified as "diffuse midline glioma" according to the WHO CNS5 nomenclature, expanding the DMG demographic. Limited therapeutic options result in a poor prognosis, despite advances in diagnosis and treatment. Radiotherapy has historically been the primary treatment modality to improve patient survival. Methods: This systematic literature review aims to comprehensively compile information on the diagnosis and treatment of DMG from 1 January 2012 to 31 July 2023. The review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and utilized databases such as PubMed, Cochrane Library, and SciELO. Results: Currently, molecular classification of DMG plays an increasingly vital role in determining prognosis and treatment options. Emerging therapeutic avenues, including immunomodulatory agents, anti-GD2 CAR T-cell and anti-GD2 CAR-NK therapies, techniques to increase blood-brain barrier permeability, isocitrate dehydrogenase inhibitors, oncolytic and peptide vaccines, are being explored based on the tumor's molecular composition. However, more clinical trials are required to establish solid guidelines for toxicity, dosage, and efficacy. Conclusions: The identification of the H3K27 genetic mutation has led to the reclassification of certain midline tumors, expanding the DMG demographic. The field of DMG research continues to evolve, with encouraging findings that underscore the importance of highly specific and tailored therapeutic strategies to achieve therapeutic success.

RESUMEN

Background: Kawasaki disease (KD) is a vasculitis associated with vascular injury and autoimmune response. Inflammatory factors stimulate neutrophils to produce web-like structures called neutrophil extracellular traps (NETs). Citrullinated histone 3 (H3Cit) is one of the main protein components of neutrophil extracellular traps involved in the process of NETosis. The levels of NETs and H3Cit in the KD are not known. Objective: To determine the changes in the levels of NETs and H3Cit in KD. Methods: Children with KD were recruited and divided into the acute KD and the sub-acute KD group according to the disease phase and whether intravenous immunoglobulin (IVIG) was used or not. Peripheral venous blood was taken before and after the IVIG administration and sent for the examination of NETs by flow cytometry. The level of H3Cit was measured by enzyme-linked immunosorbent assay (ELISA). Results: The counts of NETs in the acute KD group significantly increased compared with the healthy controls (p<0.01). The level of H3Cit was significantly higher in the acute KD group than in the healthy control subjects. Of note, both the counts of NETs and the level of H3Cit decreased in the KD patients treated with IVIG compared with the acute KD group (p<0.01). Conclusion: Acute KD is characterized by an increased formation of NETs and high levels of H3Cit. IVIG significantly inhibited NETs formation and also reduced the level of plasma H3Cit in children with KD.

Asunto(s)

Trampas Extracelulares , Síndrome Mucocutáneo Linfonodular , Niño , Humanos , Histonas/química , Histonas/metabolismo , Trampas Extracelulares/metabolismo , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Síndrome Mucocutáneo Linfonodular/metabolismo , Inmunoglobulinas Intravenosas/uso terapéutico , Neutrófilos

RESUMEN

BACKGROUND AND OBJECTIVES: In diffuse glioma patients, Lys-27-Met mutations in histone 3 genes (H3K27M) are associated with an aggravated prognosis and further decreased overall survival. By using frequency importance analysis on chemical exchange saturation transfer (CEST) MRI, this study aimed to assess the predictability of the H3K27M status in diffuse glioma patients. METHODS: Twenty-two patients diagnosed with diffuse glioma, with a known H3K27M status, were included in the present study. All patients underwent CEST MRI scans. The previously proposed frequency importance analysis was performed to determine the relative contribution of the amide and aliphatic protons for the differentiation between normal tissues and tumors. For this comparison, the conventional MTRasym analysis of amide protons at 3.5 ppm, i.e., the amide proton transfer-weighted (APTw) signal, was employed. Statistical analysis was performed using the Mann-Whitney U test, and the receiver operating characteristic (ROC) and area under the curve (AUC) analyses. RESULTS: The mean and 90th percentile of the ΔAPTw intensities, amide and aliphatic frequency importance values revealed statistically significant differences between the wildtype and the H3K27M-altered patient groups (p < 0.05). For the prediction of the H3K27M status, amide frequency importance achieved highest AUCs of 0.97, with a specificity of 0.93. In contrast, the ΔAPTw intensities and aliphatic frequency importance showed relatively lower AUCs (<0.35) in predicting the H3K27M status. CONCLUSIONS: Amide frequency importance exhibited satisfactory performance in the prediction of the H3K27M status. As such, it may be considered as a non-invasive MRI biomarker for the diagnosis of diffuse gliomas.

Asunto(s)

Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/patología , Protones , Glioma/diagnóstico por imagen , Glioma/patología , Imagen por Resonancia Magnética , Amidas

RESUMEN

High-content fluorescence microscopy combines the efficiency of high-throughput techniques with the ability to extract quantitative information from biological systems. Here we describe a modular collection of assays adapted for fixed planarian cells that enable multiplexed measurements of biomarkers in microwell plates. These include protocols for RNA fluorescent in situ hybridization (RNA FISH) as well as immunocytochemical protocols for quantifying proliferating cells targeting phosphorylated histone H3 as well as 5-bromo-2'-deoxyuridine (BrdU) incorporated into the nuclear DNA. The assays are compatible with planarians of virtually any size, as the tissue is disaggregated into a single-cell suspension before fixation and staining. By sharing many reagents with established planarian whole-mount staining protocols, preparation of samples for high-content microscopy adoption requires little additional investment.

Asunto(s)

Planarias , ARN , Animales , Hibridación Fluorescente in Situ/métodos , ARN/genética , Planarias/genética , Inmunohistoquímica , Hibridación in Situ , Microscopía Fluorescente , Bromodesoxiuridina

RESUMEN

Heparanase (HPA) is believed that might mediate histone 3 lysine 9 acetylation (H3K9ac) to regulate vascular endothelial growth factor (VEGF) gene expressions in the hyperglycemia and hypoxia human retinal endothelial cells (HRECs). Cultured human retinal endothelial cells (HRECs) in hyperglycemia, hypoxia, siRNA, and normal medium, respectively. Distributions of H3K9ac and HPA in HRECs were analyzed by immunofluorescence. Western blot and real-time PCR were respectively used to evaluate the expression of HPA, H3K9ac, and VEGF. The differences in occupancies of H3K9ac and RNA polymerase II at VEGF gene promoter among three groups were studied by Chromatin immunoprecipitation (ChIP) combined with real-time PCR. Co-immunoprecipitation (Co-IP) was used to measure the status of HPA and H3K9ac. Re-ChIP was used to verify whether HPA and H3K9ac associate to the transcription of VEGF gene. HPA was consistent with that of H3K9ac in the hyperglycemia and hypoxia groups. And the fluorescent lights of H3K9ac and HPA in siRNA groups were similar to the control group, fainter than that of hyperglycemia, hypoxia, and non-silencing groups. Western blot results showed that the expressions of HPA, H3K9ac, and VEGF in hyperglycemia and hypoxia HRECs were statistically higher than that of the control. HPA, H3K9ac, and VEGF expressions in siRNA groups were statistically lower than hyperglycemia and hypoxia HRECs. The same trends also were found in real-time PCR. ChIP exhibited the occupancies of H3K9ac and RNA Pol II at VEGF gene promoter in hyperglycemia and hypoxia groups were significantly more increased than in the control group. Co-IP revealed that HPA combined with H3K9ac in hyperglycemia and hypoxia groups; while it was not discovered in the control group. Re-ChIP showed that HPA combined with H3K9ac at VEGF gene promoter in the hyperglycemia and hypoxia HRECs nuclear. In our study HPA can influence expressions of H3K9ac and VEGF in the hyperglycemia and hypoxia HRECs. HPA can probably combine with H3K9ac and regulate the transcription of the VEGF gene in the hyperglycemia and hypoxia HRECs.

Asunto(s)

Células Endoteliales , Hiperglucemia , Humanos , Células Endoteliales/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Histonas/genética , Acetilación , Hiperglucemia/genética , Hiperglucemia/metabolismo , Células Cultivadas , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transcripción Genética , Hipoxia/genética , Hipoxia/metabolismo

RESUMEN

Nuclear receptor-binding SET domain 3, otherwise known as NSD3, is a member of the group of lysine methyltransferases and is involved in a variety of cellular processes, including transcriptional regulation, DNA damage repair, non-histone related functions and several others. NSD3 gene is mutated or loss of function in a variety of cancers, including breast, lung, pancreatic, and osteosarcoma. These mutations produce dysfunction of the corresponding tumor tissue proteins, leading to tumorigenesis, progression, chemoresistance, and unfavorable prognosis, which suggests that the development of NSD3 probe molecules is important for understanding the specific role of NSD3 in disease and drug discovery. In recent years, NSD3 has been increasingly reported, demonstrating that this target is a very hot epigenetic target. However, the number of NSD3 inhibitors available for cancer therapy is limited and none of the drugs that target NSD3 are currently available on the market. In addition, there are very few reviews describing NSD3. Within this review, we highlight the role of NSD3 in tumorigenesis and the development of NSD3 targeted small-molecule inhibitors over the last decade. We hope that this publication can serve as a guide for the development of potential drug candidates for various diseases in the field of epigenetics, especially for the NSD3 target.

Asunto(s)

Neoplasias Óseas , Osteosarcoma , Humanos , Proteínas Nucleares/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Carcinogénesis

RESUMEN

Activated toll-like receptor (TLR) signaling has been well investigated in major depressive disorder (MDD). We previously reported that TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 play important roles in regulating the toll-like receptor 4 (TLR4) signaling pathway and may serve as novel targets in the pathogenesis of MDD. Recently, aberrant histone modification has been implicated in several psychiatric disorders, including schizophrenia and mood disorder; the most thoroughly studied modification is histone 3 lysine 4 tri-methylation (H3K4me3). In this work, we aimed to explore H3K4me3 differences in the promotors of genes encoding the abovementioned factors in patients with MDD, and whether they were altered after antidepressant treatment. A total of 30 MDD patients and 28 healthy controls were recruited. Peripheral blood mononuclear cells (PBMCs) were collected. The levels of H3K4me3 in the promoters of TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 were measured through chromatin immunoprecipitation (ChIP) followed by DNA methylation assay. Analysis of covariance was used to evaluate between-group differences after adjusting for age, sex, BMI, and smoking. In comparison with healthy controls, patients with MDD showed significantly lower H3K4me3 levels in the promoters of TNFAIP3, TLR4, TNIP2, miR-146a, and miR-155 in PBMCs. These levels were not significantly altered after completion of a 4-week antidepressant treatment. To explore the association between depression severity and H3K4me3 levels, a multiple linear regression model was generated. The results revealed that levels of H3K4me3 in the TNIP2 promoters a negative correlation with the 17-item Hamilton Depression Rating Scale (HAND-17) score, whereas that of TLR4 had a positive correlation with this score. The present results suggest that decreased H3K4me3 levels in the promoters of the genes encoding TNFAIP3, TLR4, miR-146a, miR-155, and TNIP2 are involved in psychopathology of major depressive disorder.

Asunto(s)

Trastorno Depresivo Mayor , MicroARNs , Humanos , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Trastorno Depresivo Mayor/tratamiento farmacológico , Leucocitos Mononucleares/metabolismo , Código de Histonas , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , MicroARNs/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/genética , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/uso terapéutico , Proteínas Adaptadoras Transductoras de Señales/metabolismo

RESUMEN

Chromatin is a dynamic platform within which gene expression is controlled by epigenetic modifications, notably targeting amino acid residues of histone H3. Among them is lysine 27 of H3 (H3K27), the trimethylation of which by the Polycomb Repressive Complex 2 (PRC2) is instrumental in regulating spatiotemporal patterns of key developmental genes. H3K27 is also subjected to acetylation and is found at sites of active transcription. Most information on the function of histone residues and their associated modifications in plants was obtained from studies of loss-of-function mutants for the complexes that modify them. To decrypt the genuine function of H3K27, we expressed a non-modifiable variant of H3 at residue K27 (H3.3K27A ) in Arabidopsis, and developed a multi-scale approach combining in-depth phenotypical and cytological analyses, with transcriptomics and metabolomics. We uncovered that the H3.3K27A variant causes severe developmental defects, part of them are reminiscent of PRC2 mutants, part of them are new. They include early flowering, increased callus formation and short stems with thicker xylem cell layer. This latest phenotype correlates with mis-regulation of phenylpropanoid biosynthesis. Overall, our results reveal novel roles of H3K27 in plant cell fates and metabolic pathways, and highlight an epigenetic control point for elongation and lignin composition of the stem.

Asunto(s)

Arabidopsis , Histonas , Histonas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Lisina/metabolismo , Lignina/metabolismo , Metilación , Epigénesis Genética , Genes del Desarrollo

RESUMEN

Methylating RNA post-transcriptionally is emerging as a significant mechanism of gene regulation in eukaryotes. The crosstalk between RNA methylation and histone modification is critical for chromatin state and gene expression in mammals. However, it is not well understood mechanistically in plants. Here, the authors report a genome-wide correlation between RNA 5-cytosine methylation (m5 C) and histone 3 lysine27 trimethylation (H3K27me3) in Arabidopsis. The plant-specific Polycomb group (PcG) protein EMBRYONIC FLOWER1 (EMF1) plays dual roles as activators or repressors. Transcriptome-wide RNA m5 C profiling revealed that m5 C peaks are mostly enriched in chromatin regions that lacked H3K27me3 in both wild type and emf1 mutants. EMF1 repressed the expression of m5 C methyltransferase tRNA specific methyltransferase 4B (TRM4B) through H3K4me3, independent of PcG-mediated H3K27me3 mechanism. The 5-Cytosine methylation on targets is increased in emf1 mutants, thereby decreased the mRNA transcripts of photosynthesis and chloroplast genes. In addition, impairing EMF1 activity reduced H3K27me3 levels of PcG targets, such as starch genes, which are de-repressed in emf1 mutants. Both EMF1-mediated promotion and repression of gene activities via m5 C and H3K27me3 are required for normal vegetative growth. Collectively, t study reveals a previously undescribed epigenetic mechanism of RNA m5 C modifications and histone modifications to regulate gene expression in eukaryotes.