RESUMEN
The fetal-to-adult hemoglobin switch is regulated in a developmental stage-specific manner and reactivation of fetal hemoglobin (HbF) has therapeutic implications for treatment of ß-thalassemia and sickle cell anemia, two major global health problems. Although significant progress has been made in our understanding of the molecular mechanism of the fetal-to-adult hemoglobin switch, the mechanism of epigenetic regulation of HbF silencing remains to be fully defined. Here, we performed whole-genome bisulfite sequencing and RNA sequencing analysis of the bone marrow-derived GYPA+ erythroid cells from ß-thalassemia-affected individuals with widely varying levels of HbF groups (HbF ≥ 95th percentile or HbF ≤ 5th percentile) to screen epigenetic modulators of HbF and phenotypic diversity of ß-thalassemia. We identified an ETS2 repressor factor encoded by ERF, whose promoter hypermethylation and mRNA downregulation are associated with high HbF levels in ß-thalassemia. We further observed that hypermethylation of the ERF promoter mediated by enrichment of DNMT3A leads to demethylation of γ-globin genes and attenuation of binding of ERF on the HBG promoter and eventually re-activation of HbF in ß-thalassemia. We demonstrated that ERF depletion markedly increased HbF production in human CD34+ erythroid progenitor cells, HUDEP-2 cell lines, and transplanted NCG-Kit-V831M mice. ERF represses γ-globin expression by directly binding to two consensus motifs regulating γ-globin gene expression. Importantly, ERF depletion did not affect maturation of erythroid cells. Identification of alterations in DNA methylation of ERF as a modulator of HbF synthesis opens up therapeutic targets for ß-hemoglobinopathies.
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Epigénesis Genética , Perfilación de la Expresión Génica , Proteínas Represoras/deficiencia , Proteínas Represoras/genética , Talasemia beta/genética , gamma-Globinas/genética , Animales , Antígenos CD34/metabolismo , Secuencia de Bases , Sistemas CRISPR-Cas/genética , Diferenciación Celular , Línea Celular , Niño , ADN (Citosina-5-)-Metiltransferasas/genética , Metilación de ADN , ADN Metiltransferasa 3A , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/metabolismo , Femenino , Hemoglobina Fetal/genética , Edición Génica , Humanos , Masculino , Ratones , Regiones Promotoras Genéticas/genética , Reproducibilidad de los Resultados , Sulfitos , Secuenciación Completa del Genoma , Talasemia beta/patologíaRESUMEN
Fetal-to-adult hemoglobin switching is controlled by programmed silencing of γ-globin while the re-activation of fetal hemoglobin (HbF) is an effective strategy for ameliorating the clinical severity of ß-thalassemia and sickle cell disease. The identification of enhancer RNAs (eRNAs) related to the fetal (α2γ2) to adult hemoglobin (α2ß2) switching remains incomplete. In this study, the transcriptomes of GYPA+ cells from six ß-thalassemia patients with extreme HbF levels were sequenced to identify differences in patterns of noncoding RNA expression. It is interesting that an enhancer upstream of CHD4, an HbF-related core subunit of the NuRD complex, was differentially transcribed. We found a significantly positive correlation of eRNA-CHD4 enhancer-gene interaction using the public database of FANTOM5. Specifically, the eRNA-CHD4 expression was found to be significantly higher in both CD34+ HSPCs and HUDEP-2 than those in K562 cells which commonly expressed high level of HbF, suggesting a correlation between eRNA and HbF expression. Furthermore, prediction of transcription binding sites of cis-eQTLs and the CHD4 genomic region revealed a putative interaction site between rs73264846 and ZNF410, a known transcription factor regulating HbF expression. Moreover, in-vitro validation showed that the inhibition of eRNA could reduce the expression of HBG expression in HUDEP-2 cells. Taken together, the findings of this study demonstrate that a distal enhancer contributes to stage-specific silencing of γ-globin genes through direct modulation of CHD4 expression and provide insights into the epigenetic mechanisms of NuRD-mediated hemoglobin switching.
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Anemia de Células Falciformes , Talasemia beta , Adulto , Humanos , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , gamma-Globinas/genética , gamma-Globinas/metabolismo , Talasemia beta/genética , Regulación de la Expresión Génica , Anemia de Células Falciformes/genética , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/genética , Complejo Desacetilasa y Remodelación del Nucleosoma Mi-2/metabolismoRESUMEN
OBJECTIVE: Benign prostatic hyperplasia (BPH) is common in elder men. The current study aims to identify differentially expressed genes (DEGs) in hyperplastic prostate and to explore the role of Nik related kinase (NRK) in BPH. METHODS: Four datasets including three bulk and one single cell RNA-seq (scRNA-seq) were obtained to perform integrated bioinformatics. Cell clusters and specific metabolism pathways were analyzed. The localization, expression and functional activity of NRK was investigated via RT-PCR, western-blot, immunohistochemical staining, flow cytometry, wound healing assay, transwell assay and CCK-8 assay. RESULTS: A total of 17 DEGs were identified by merging three bulk RNA-seq datasets. The findings of integrated single-cell analysis showed that NRK remarkably upregulated in fibroblasts and SM cells of hyperplasia prostate. Meanwhile, NRK was upregulated in BPH samples and localized almost in stroma. The expression level of NRK was significantly correlated with IPSS and Qmax of BPH patients. Silencing of NRK inhibited stromal cell proliferation, migration, fibrosis and EMT process, promoted apoptosis and induced cell cycle arrest, while overexpression of NRK in prostate epithelial cells showed opposite results. Meanwhile, induced fibrosis and EMT process were rescued by knockdown of NRK. Furthermore, expression level of NRK was positively correlated with that of α-SMA, collagen-I and N-cadherin, negatively correlated with that of E-cadherin. CONCLUSION: Our novel data identified NRK was upregulated in hyperplastic prostate and associated with prostatic stromal cell proliferation, apoptosis, cell cycle, migration, fibrosis and EMT process. NRK may play important roles in the development of BPH and may be a promising therapeutic target for BPH/LUTS.
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Péptidos y Proteínas de Señalización Intracelular , Próstata , Hiperplasia Prostática , Proteínas Serina-Treonina Quinasas , Masculino , Humanos , Anciano , Próstata/metabolismo , Hiperplasia/metabolismo , Hiperplasia/patología , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patología , FibrosisRESUMEN
Palladium-catalyzed decarboxylation of 5-methylene-1,3-oxazinan-2-ones and 5-methylene-1,3-dioxan-2-ones to generate aza-π-allylpalladium and oxa-π-allylpalladium 1,4-dipoles for [4 + 2] cycloaddition reaction with 1,3,5-triazinanes was developed, affording a wide range of hexahydropyrimidine and 1,3-oxazinane derivatives in good to excellent yields (up to 99%). The acyclic sulfonamido-substituted allylic carbonates as aza-π-allylpalladium 1,4-dipole precursors also apply to the developed synthesized strategy, achieving the synthesis of hexahydropyrimidines. Moreover, the in situ-generated aza-π-allylpalladium 1,4-dipoles undergoing dimeric [4 + 4] cycloaddition were also demonstrated by the construction of 1,5-diazocane derivatives.
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circACTA2 derived from the smooth muscle α-actin gene plays an important role in the regulation of vascular smooth muscle cell (VSMC) phenotype. The activation of NLRP3 inflammasome is involved in VSMC phenotypic switching. However, the mechanistic relationship between circACTA2 and NLRP3 inflammasome during vascular remodeling remains poorly understood. Here, we showed that circACTA2 was down-regulated in human intimal hyperplasia. circACTA2 overexpression in circACTA2 transgenic mice significantly decreased the neointimal hyperplasia induced by vascular injury, which is concomitant with a decrease in IL-18, IL-1ß, TNF-α, and IL-6 levels. Gain- and loss-of-function studies revealed that circACTA2 alleviated VSMC inflammation by suppressing the activation of NLRP3 inflammasome. Mechanistically, circACTA2 inhibited the expression of NF-κB p65 and p50 subunits and interacted with p50, which impedes the formation of the p50/p65 heterodimer and nuclear translocation induced by TNF-α, thus resulting in the suppression of NLRP3 gene transcription and inflammasome activation. Furthermore, circACTA2 overexpression mitigated inflammation via repressing NLRP3 inflammasome-mediated VSMC pyroptosis. Importantly, employing a decoy oligonucleotide to compete with circACTA2 for binding to p50 could attenuate the expression of NLRP3, ASC, and caspase-1. These findings provide a novel insight into the functional roles of circACTA2 in VSMCs, and targeting the circACTA2-NF-κB-NLRP3 axis represents a promising therapeutic strategy for vascular remodeling.
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Inflamasomas , FN-kappa B , Ratones , Animales , Humanos , FN-kappa B/metabolismo , Inflamasomas/genética , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Músculo Liso Vascular/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Remodelación Vascular , Hiperplasia/metabolismo , Inflamación/patologíaRESUMEN
BACKGROUND: Observational studies have suggested an association between birth weight and type 2 diabetes mellitus, but the causality between them has not been established. We aimed to obtain the causal relationship between birth weight with T2DM and quantify the mediating effects of potential modifiable risk factors. METHODS: Two-step, two-sample Mendelian randomization (MR) techniques were applied using SNPs as genetic instruments for exposure and mediators. Summary data from genome-wide association studies (GWAS) for birth weight, T2DM, and a series of fatty acids traits and their ratios were leveraged. The inverse variance weighted (IVW) method was the main analysis approach. In addition, the heterogeneity test, horizontal pleiotropy test, Mendelian randomization pleiotropy residual sum and outlier (MR-PRESSO) test, and leave-one-out analysis were carried out to assess the robustness. RESULTS: The IVW method showed that lower birth weight raised the risk of T2DM (ß: -1.113, 95% CI: -1.573 â¼ -0.652). Two-step MR identified 4 of 17 candidate mediators partially mediating the effect of lower birth weight on T2DM, including ratio of polyunsaturated fatty acids to monounsaturated fatty acids (proportion mediated: 7.9%), ratio of polyunsaturated fatty acids to total fatty acids (7.2%), ratio of omega-6 fatty acids to total fatty acids (8.1%) and ratio of linoleic acid to total fatty acids ratio (6.0%). CONCLUSIONS: Our findings supported a potentially causal effect of birth weight against T2DM with considerable mediation by modifiable risk factors. Interventions that target these factors have the potential to reduce the burden of T2DM attributable to low birth weight.
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Diabetes Mellitus Tipo 2 , Ácidos Grasos , Humanos , Diabetes Mellitus Tipo 2/genética , Peso al Nacer/genética , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Ácidos Grasos MonoinsaturadosRESUMEN
Extracellular polymeric substances (EPS) are a critical influencing factor in sludge dewatering. Disrupting such EPS contributes to the release of bound water in sludge, enhancing the sludge dewatering performance. In This study, quaternized straw fibers that are destructive to the EPS structure and components in active sludge were prepared useing heterogeneous free radical graft polymerization. Straw fibers, dimethyl diallyl ammonium chloride (DMDAAC), ammonium persulfate (APS), and acrylamide (AM) were taken as the substrate, grafting monomer, catalyst, and cross-linking agent, respectively.The optimal processing conditions determined for the DMDAAC-based quaternization and graft modification of straw fibers were as follows: reaction temperature of 60 °C, reaction time of 5 h, 0.100 g of catalyst APS dosage per gram of straw, and 3.000 ml of DMDAAC dosage per gram of straw. The optimal processing conditions yielded 1.335 g of modified straw fibers per gram of straw, 33.67% grafting rate, and 31.70% substitution of the quaternary ammonium groups. The capillary suction time (CST) was conditioned from 243.3 ± 22.6 s in the original sludge to 134.5 ± 34.45 s. The specific resistance to filtration (SRF) was reduced from 8.82 ± 0.51 × 1012 m/kg in the original sludge to 4.59 ± 0.23 × 1012 m/kg.
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Aguas del Alcantarillado , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Compuestos de Amonio Cuaternario/química , Compuestos Alílicos/químicaRESUMEN
OBJECTIVES: To investigate the clinical characteristics and prognosis of pneumococcal meningitis (PM), and drug sensitivity of Streptococcus pneumoniae (SP) isolates in Chinese children. METHODS: A retrospective analysis was conducted on clinical information, laboratory data, and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country. RESULTS: Among the 160 children with PM, there were 103 males and 57 females. The age ranged from 15 days to 15 years, with 109 cases (68.1%) aged 3 months to under 3 years. SP strains were isolated from 95 cases (59.4%) in cerebrospinal fluid cultures and from 57 cases (35.6%) in blood cultures. The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87) and 27% (21/78), respectively. Fifty-five cases (34.4%) had one or more risk factors for purulent meningitis, 113 cases (70.6%) had one or more extra-cranial infectious foci, and 18 cases (11.3%) had underlying diseases. The most common clinical symptoms were fever (147 cases, 91.9%), followed by lethargy (98 cases, 61.3%) and vomiting (61 cases, 38.1%). Sixty-nine cases (43.1%) experienced intracranial complications during hospitalization, with subdural effusion and/or empyema being the most common complication [43 cases (26.9%)], followed by hydrocephalus in 24 cases (15.0%), brain abscess in 23 cases (14.4%), and cerebral hemorrhage in 8 cases (5.0%). Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old, with rates of 91% (39/43) and 83% (20/24), respectively. SP strains exhibited complete sensitivity to vancomycin (100%, 75/75), linezolid (100%, 56/56), and meropenem (100%, 6/6). High sensitivity rates were also observed for levofloxacin (81%, 22/27), moxifloxacin (82%, 14/17), rifampicin (96%, 25/26), and chloramphenicol (91%, 21/23). However, low sensitivity rates were found for penicillin (16%, 11/68) and clindamycin (6%, 1/17), and SP strains were completely resistant to erythromycin (100%, 31/31). The rates of discharge with cure and improvement were 22.5% (36/160) and 66.2% (106/160), respectively, while 18 cases (11.3%) had adverse outcomes. CONCLUSIONS: Pediatric PM is more common in children aged 3 months to under 3 years. Intracranial complications are more frequently observed in children under 1 year old. Fever is the most common clinical manifestation of PM, and subdural effusion/emphysema and hydrocephalus are the most frequent complications. Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates. Adverse outcomes can be noted in more than 10% of PM cases. SP strains are high sensitivity to vancomycin, linezolid, meropenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol.
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Empiema , Hidrocefalia , Meningitis Neumocócica , Efusión Subdural , Lactante , Femenino , Masculino , Humanos , Niño , Recién Nacido , Adolescente , Meningitis Neumocócica/tratamiento farmacológico , Meningitis Neumocócica/epidemiología , Meropenem , Vancomicina , Levofloxacino , Linezolid , Moxifloxacino , Estudios Retrospectivos , Rifampin , Streptococcus pneumoniae , CloranfenicolRESUMEN
Amyloid-ß1-42 (Aß1-42 ) is strongly associated with Alzheimer's disease (AD). The aim of this study is to elucidate whether and how miR-6076 participates in the modulation of amyloid-ß (Aß)-induced neuronal damage. To construct the neuronal damage model, SH-SY5Y cells were treated with Aß1-42 . By qRT-PCR, we found that miR-6076 is significantly upregulated in Aß1-42 -treated SH-SY5Y cells. After miR-6076 inhibition, p-Tau and apoptosis levels were downregulated, and cell viability was increased. Through online bioinformatics analysis, we found that B-cell lymphoma 6 (BCL6) was a directly target of miR-6076 via dual-luciferase reporter assay. BCL6 overexpression mediated the decrease in elevated p-Tau levels and increased viability in SH-SY5Y cells following Aß1-42 treatment. Our results suggest that down-regulation of miR-6076 could attenuate Aß1-42 -induced neuronal damage by targeting BCL6, which provided a possible target to pursue for prevention and treatment of Aß-induced neuronal damage in AD.
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Enfermedad de Alzheimer , MicroARNs , Neuroblastoma , Humanos , MicroARNs/genética , Línea Celular Tumoral , Péptidos beta-Amiloides/toxicidad , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Apoptosis/genética , Fragmentos de Péptidos/farmacología , Proteínas Proto-Oncogénicas c-bcl-6/genéticaRESUMEN
Neural stem cells (NSCs) persist in the dentate gyrus of the hippocampus into adulthood and are essential for both neurogenesis and neural circuit integration. Exosomes have also been shown to play vital roles in regulating biological processes of receptor cells as a medium for cell-to-cell communication signaling molecules. The precise molecular mechanisms of exosome-mediated signaling, however, remain largely unknown. Here, we found that exosomes produced by denervated hippocampi following fimbria-fornix transection could promote the differentiation of hippocampal neural precursor cells into cholinergic neurons in coculture with NSCs. Furthermore, we found that 14 circular RNAs (circRNAs) were upregulated in hippocampal exosomes after fimbria-fornix transection using high-throughput RNA-Seq technology. We further characterized the function and mechanism by which the upregulated circRNA Acbd6 (acyl-CoA-binding domain-containing 6) promoted the differentiation of NSCs into cholinergic neurons using RT-quantitative PCR, Western blot, ELISA, flow cytometry, immunohistochemistry, and immunofluorescence assay. By luciferase reporter assay, we demonstrated that circAcbd6 functioned as an endogenous miR-320-5p sponge to inhibit miR-320-5p activity, resulting in increased oxysterol-binding protein-related protein 2 expression with subsequent facilitation of NSC differentiation. Taken together, our results suggest that circAcbd6 promotes differentiation of NSCs into cholinergic neurons via miR-320-5p/oxysterol-binding protein-related protein 2 axis, which contribute important insights to our understanding of how circRNAs regulate neurogenesis.
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Diferenciación Celular , Neuronas Colinérgicas , MicroARNs , Células-Madre Neurales , ARN Circular , Receptores de Esteroides , Animales , Diferenciación Celular/genética , Neuronas Colinérgicas/citología , MicroARNs/genética , MicroARNs/metabolismo , Células-Madre Neurales/citología , ARN Circular/genética , ARN Circular/metabolismo , Ratas , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismoRESUMEN
Mesenchymal gastrointestinal cancers are represented by the gastrointestinal stromal tumors (GISTs) which occur throughout the whole gastrointestinal tract, and affect human health and economy globally. Curative surgical resections and tyrosine kinase inhibitors (TKIs) are the main managements for localized GISTs and recurrent/metastatic GISTs, respectively. Despite multi-lines of TKIs treatments prolonged the survival time of recurrent/metastatic GISTs by delaying the relapse and metastasis of the tumor, drug resistance developed quickly and inevitably, and became the huge obstacle for stopping disease progression. Immunotherapy, which is typically represented by immune checkpoint inhibitors (ICIs), has achieved great success in several solid tumors by reactivating the host immune system, and been proposed as an alternative choice for GIST treatment. Substantial efforts have been devoted to the research of immunology and immunotherapy for GIST, and great achievements have been made. Generally, the intratumoral immune cell level and the immune-related gene expressions are influenced by metastasis status, anatomical locations, driver gene mutations of the tumor, and modulated by imatinib therapy. Systemic inflammatory biomarkers are regarded as prognostic indicators of GIST and closely associated with its clinicopathological features. The efficacy of immunotherapy strategies for GIST has been widely explored in pre-clinical cell and mouse models and clinical experiments in human, and some patients did benefit from ICIs. This review comprehensively summarizes the up-to-date advancements of immunology, immunotherapy and research models for GIST, and provides new insights and perspectives for future studies.
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Antineoplásicos , Neoplasias Gastrointestinales , Tumores del Estroma Gastrointestinal , Sarcoma , Animales , Ratones , Humanos , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/terapia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Gastrointestinales/terapia , Neoplasias Gastrointestinales/patología , Sarcoma/tratamiento farmacológico , Inmunoterapia , Antineoplásicos/uso terapéutico , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/uso terapéuticoRESUMEN
BACKGROUND: The pathogenesis of benign prostatic hyperplasia (BPH) has not been fully elucidated. Ras homology family member A (RhoA) plays an important role in regulating cell cytoskeleton, growth and fibrosis. The role of RhoA in BPH remains unclear. METHODS: This study aimed to clarify the expression, functional activity and mechanism of RhoA in BPH. Human prostate tissues, human prostate cell lines, BPH rat model were used. Cell models of RhoA knockdown and overexpression were generated. Immunofluorescence staining, quantitative real time PCR (qRT-PCR), Western blotting, cell counting kit-8 (CCK-8), flow cytometry, phalloidine staining, organ bath study, gel contraction assay, protein stability analysis, isolation and extraction of nuclear protein and cytoplasmic protein were performed. RESULTS: In this study we found that RhoA was localized in prostate stroma and epithelial compartments and was up-regulated in both BPH patients and BPH rats. Functionally, RhoA knockdown induced cell apoptosis and inhibited cell proliferation, fibrosis, epithelial-mesenchymal transformation (EMT) and contraction. Consistently, overexpression of RhoA reversed all aforementioned processes. More importantly, we found that ß-catenin and the downstream of Wnt/ß-catenin signaling, including C-MYC, Survivin and Snail were up-regulated in BPH rats. Downregulation of RhoA significantly reduced the expression of these proteins. Rho kinase inhibitor Y-27632 also down-regulated ß-catenin protein in a concentration-dependent manner. However, overexpression of ß-catenin did not affect RhoA-ROCK levels, suggesting that ß-catenin was the downstream of RhoA-ROCK regulation. Further data suggested that RhoA increased nuclear translocation of ß-catenin and up-regulated ß-catenin expression by inhibiting its proteasomal degradation, thereby activating Wnt/ß-catenin signaling. Overexpression of ß-catenin partially reversed the changes in cell growth, fibrosis and EMT except cell contraction caused by RhoA downregulation. Finally, Y-27632 partially reversed prostatic hyperplasia in vivo, further suggesting the potential of RhoA-ROCK signaling in BPH treatment. CONCLUSION: Our novel data demonstrated that RhoA regulated both static and dynamic factors of BPH, RhoA-ROCK-ß-catenin signaling axis played an important role in the development of BPH and might provide more possibilities for the formulation of subsequent clinical treatment strategies.
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Hiperplasia Prostática , Animales , Humanos , Masculino , Ratas , beta Catenina/metabolismo , Proliferación Celular , Fibrosis , Hiperplasia Prostática/genética , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patología , Vía de Señalización WntRESUMEN
Gastrointestinal stromal tumors are the most common mesenchymal tumors of the digestive tract, most of which are sporadic, and familial GISTs with germline mutations are rarely seen. Here, we report a 26-year-old female with a germline p. W557R mutation in exon 11 of the KIT gene. The proband and her father and sister presented with multifocal GIST and pigmented nevi. All 3 patients underwent surgery and imatinib therapy. To date, only 49 kindreds with germline KIT mutations and 6 kindreds with germline PDGFRA mutations have been reported. Summarizing the reported kindreds, the majority of familial GISTs manifest as multiple primary GISTs complicated with special clinical manifestations, including cutaneous hyperpigmentation, dysphagia, mastocytosis, inflammatory fibrous polyps, and large hands. Familial GISTs are generally thought to exhibit TKI sensitivity similar to that of sporadic GISTs with the same mutation.
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Tumores del Estroma Gastrointestinal , Síndromes Neoplásicos Hereditarios , Femenino , Humanos , Adulto , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Pronóstico , Mesilato de Imatinib/uso terapéutico , Mutación , Mutación de Línea Germinal , Proteínas Proto-Oncogénicas c-kit/genéticaRESUMEN
BACKGROUND: Anlotinib is a multi-target tyrosine kinase inhibitor that can effectively inhibit tumor cell proliferation after receptor kinase activation caused by KIT gene mutation. METHODS: We tested the inhibitory effect of anlotinib in GIST cell lines with different gene mutations and evaluated the efficacy of anlotinib for patients with metastatic GIST after imatinib failure in a multicenter, single-arm, phase II study. RESULTS: In vitro, V654A mutation encoded by KIT exon 13 was intermediately sensitive to anlotinib. Moreover, anlotinib was able to partly suppress the activation loop mutation D820A from exon 17 while another activation loop mutation N822K, also from exon 17, was resistant to anlotinib. From September 2018 to October 2020, 64 patients from 9 Chinese medical centers were enrolled in this study. Seven patients had partial response and 39 patients had stable disease. The median PFS was 8.0 months. There was no statistical significance comparing with PFS of sunitinib second-line therapy at the same period. The most common adverse events related to anlotinib treatment were hypertension, neutropenia, and fatigue. CONCLUSION: Anlotinib showed moderate antitumor activity in drug-resistant GIST cell lines in vitro, and good PFS and better tolerance in second-line therapy study.
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Antineoplásicos , Tumores del Estroma Gastrointestinal , Humanos , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Estudios Prospectivos , Sunitinib/uso terapéutico , Mutación , Proteínas Proto-Oncogénicas c-kit/genética , Resistencia a Antineoplásicos/genéticaRESUMEN
BACKGROUND: Avapritinib is a type 1 kinase inhibitor designed to potently and selectively inhibit oncogenic KIT/PDGFRA mutants by targeting the kinase active conformation. This multicenter, single-arm, open-label, phase I/II bridging study of NAVIGATOR in Chinese patients evaluated the safety and the antineoplastic activity of avapritinib in Chinese patients with unresectable/metastatic gastrointestinal stromal tumors (GIST). METHODS: Phase I comprised dose escalation for safety and phase II dose determination. Phase II comprised dose expansion for safety/efficacy evaluations in patients with PDGFRA D842V mutations or patients having received at least 3 lines of therapy without PDGFRA D842V mutations. The primary endpoints were recommended phase II dose, safety, and Independent Radiology Review Committee (IRRC)-assessed objective response rate (ORR). RESULTS: No dose-limiting toxicities occurred (n = 10); the recommended phase II dose was avapritinib 300 mg once daily orally. Fifty-nine patients initially received avapritinib 300 mg. Common grade ≥3 treatment-related adverse events were anemia, decreased white blood cell count, increased blood bilirubin levels, and decreased neutrophil count. In patients with PDGFRA D842V mutations, IRRC- and investigator-assessed ORRs were 75% and 79%, respectively; clinical benefit rates were both 86%. Median duration of response/progression-free survival were not reached. IRCC- and investigator-assessed ORRs in patients in the fourth- or later-line setting were 22% and 35%, respectively. Median progression-free survivals were 5.6 months for both. Overall survival data were immature and not calculated. CONCLUSION: Avapritinib was generally well tolerated and showed marked anti-tumor activity in Chinese patients with GIST bearing PDGFRA D842V mutations and notable efficacy as fourth- or later-line monotherapy (ClinicalTrials.gov Identifier: NCT04254939).
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Antineoplásicos , Tumores del Estroma Gastrointestinal , Humanos , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Mutación , Antineoplásicos/efectos adversos , Pirroles/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversosRESUMEN
MAIN CONCLUSION: Santalum album (E,E)-α-farnesene synthase catalyzes FPP into (E,E)-α-farnesene. Overexpression of the SaAFS gene positively improved cold stress tolerance through JA biosynthesis and signaling pathways in Arabidopsis. Volatile terpenoids are released from plants that suffer negative effects following exposure to various biotic and abiotic stresses. Recent studies revealed that (E,E)-α-farnesene synthase (AFS) plays a significant role in a plant's defence against biotic attack. However, little is known about whether AFS contributes to plant resistance to cold stress. In this study, a SaAFS gene was isolated from Indian sandalwood (Santalum album L.) and functionally characterized. The SaAFS protein mainly converts farnesyl diphosphate to (E,E)-α-farnesene. SaAFS was clustered into the AFS clade from angiosperms, suggesting a highly conserved enzyme. SaAFS displayed a significant response to cold stress and methyl jasmonate. SaAFS overexpression (OE) in Arabidopsis enhanced cold tolerance by increasing proline content, reducing malondialdehyde content, electrolyte leakage, and accumulating reactive oxygen species. Transcriptomic analysis revealed that upregulated genes related to stress response and JA biosynthesis and signaling were detected in SaAFS-OE lines compared with wild type plants that were exposed to cold stress. Endogenous JA and jasmonoyl-isoleucine content increased significantly in SaAFS-OE lines exposed to cold stress. Collectively considered, these results suggest that the SaAFS gene is a positive regulator during cold stress tolerance via JA biosynthesis and signaling pathways.
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Arabidopsis , Aceites Volátiles , Santalum , Arabidopsis/metabolismo , Santalum/genética , Santalum/metabolismo , Ciclopentanos/metabolismo , Aceites Volátiles/metabolismo , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismoRESUMEN
BACKGROUND: Benign prostatic hyperplasia (BPH) is a common disease in elderly men, mainly resulted from an imbalance between cell proliferation and death. Glutathione peroxidase 3 (GPX3) was one of the differentially expressed genes in BPH identified by transcriptome sequencing of 5 hyperplastic and 3 normal prostate specimens, which had not been elucidated in the prostate. This study aimed to ascertain the mechanism of GPX3 involved in cell proliferation, apoptosis, autophagy and ferroptosis in BPH. METHODS: Human prostate tissues, GPX3 silencing and overexpression prostate cell (BPH-1 and WPMY-1) models and testosterone-induced rat BPH (T-BPH) model were utilized. The qRT-PCR, CCK8 assay, flow cytometry, Western blotting, immunofluorescence, hematoxylin and eosin, masson's trichrome, immunohistochemical staining and transmission electron microscopy analysis were performed during in vivo and in vitro experiments. RESULTS: Our study indicated that GPX3 was localized both in the stroma and epithelium of prostate, and down-regulated in BPH samples. Overexpression of GPX3 inhibited AMPK and activated ERK1/2 pathway, thereby inducing mitochondria-dependent apoptosis and G0/G1 phase arrest, which could be significantly reversed by MEK1/2 inhibitor U0126 preconditioning. Moreover, overexpression of GPX3 further exerted anti-autophagy by inhibiting AMPK/m-TOR and up-regulated nuclear factor erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase 4 (GPX4, mitochondrial GPX4 and cytoplasmic GPX4) to antagonize autophagy-related ferroptosis. Consistently, GPX3 deficiency generated opposite changes in both cell lines. Finally, T-BPH rat model was treated with GPX3 indirect agonist troglitazone (TRO) or GPX4 inhibitor RAS-selective lethal 3 (RSL3) or TRO plus RSL3. These treatments produced significant atrophy of the prostate and related molecular changes were similar to our in vitro observations. CONCLUSIONS: Our novel data manifested that GPX3, which was capable of inducing apoptosis via AMPK/ERK1/2 pathway and antagonizing autophagy-related ferroptosis through AMPK/m-TOR signalling, was a promising therapeutic target for BPH in the future.
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Ferroptosis , Hiperplasia Prostática , Anciano , Animales , Humanos , Masculino , Ratas , Proteínas Quinasas Activadas por AMP , Apoptosis , Glutatión Peroxidasa , Hiperplasia , Sistema de Señalización de MAP Quinasas , Mitocondrias , Próstata , Serina-Treonina Quinasas TORRESUMEN
DNA methyltransferase 1 (DNMT1) is a major epigenetic regulator of the formation of large macromolecular complexes that repress human γ-globin expression by maintaining DNA methylation. However, very little is known about the association of DNMT1 variants with ß-thalassemia phenotypes. We systematically investigated associations between variants in DNMT1 and phenotypes in 1142 ß-thalassemia subjects and identified a novel missense mutation (c.2633G>A, S878F) in the DNMT1 bromo-adjacent homology-1 (BAH1) domain. We functionally characterized this mutation in CD34+ cells from patients and engineered HuDEP-2 mutant cells. Our results demonstrate that DNMT1 phosphorylation is abrogated by substituting serine with phenylalanine at position 878, resulting in lower stability and catalytic activity loss. S878F mutation also attenuated DNMT1 interactions with BCL11A, GATA1, and HDAC1/2, and reduced recruitment of DNMT1 to the γ-globin (HBG) promoters, leading to epigenetic derepression of γ-globin expression. By analyzing the F-cell pattern, we demonstrated that the effect of DNMT1 mutation on increased fetal hemoglobin (HbF) is heterocellular. Furthermore, introduction of S878F mutation into erythroid cells by clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) recapitulated γ-globin reactivation. Thus, the natural S878F DNMT1 mutation is a novel modulator of HbF synthesis and represents a potential new therapeutic target for ß-hemoglobinopathies.
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ADN (Citosina-5-)-Metiltransferasa 1/genética , Hemoglobina Fetal/genética , Talasemia beta/genética , gamma-Globinas/genética , Línea Celular , Epigénesis Genética , Humanos , Modelos Moleculares , Mutación , Regulación hacia ArribaRESUMEN
Although dysregulation of mitochondrial dynamics has been linked to cellular senescence, which contributes to advanced age-related disorders, it is unclear how Krüppel-like factor 5 (Klf5), an essential transcriptional factor of cardiovascular remodeling, mediates the link between mitochondrial dynamics and vascular smooth muscle cell (VSMC) senescence. Here, we show that Klf5 down-regulation in VSMCs is correlated with rupture of abdominal aortic aneurysm (AAA), an age-related vascular disease. Mice lacking Klf5 in VSMCs exacerbate vascular senescence and progression of angiotensin II (Ang II)-induced AAA by facilitating reactive oxygen species (ROS) formation. Klf5 knockdown enhances, while Klf5 overexpression suppresses mitochondrial fission. Mechanistically, Klf5 activates eukaryotic translation initiation factor 5a (eIF5a) transcription through binding to the promoter of eIF5a, which in turn preserves mitochondrial integrity by interacting with mitofusin 1 (Mfn1). Accordingly, decreased expression of eIF5a elicited by Klf5 down-regulation leads to mitochondrial fission and excessive ROS production. Inhibition of mitochondrial fission decreases ROS production and VSMC senescence. Our studies provide a potential therapeutic target for age-related vascular disorders.
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Aneurisma de la Aorta Abdominal/genética , Células Endoteliales/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Mitocondrias/metabolismo , Factores de Iniciación de Péptidos/genética , Proteínas de Unión al ARN/genética , Anciano , Angiotensina II/genética , Angiotensina II/metabolismo , Angiotensina II/farmacología , Animales , Aorta/diagnóstico por imagen , Aorta/metabolismo , Aorta/patología , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/metabolismo , Aneurisma de la Aorta Abdominal/patología , Senescencia Celular/efectos de los fármacos , Ecocardiografía , Células Endoteliales/patología , Femenino , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , Humanos , Factores de Transcripción de Tipo Kruppel/deficiencia , Masculino , Ratones , Ratones Noqueados , Mitocondrias/patología , Dinámicas Mitocondriales/efectos de los fármacos , Factores de Iniciación de Péptidos/deficiencia , Cultivo Primario de Células , Regiones Promotoras Genéticas , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Factor 5A Eucariótico de Iniciación de TraducciónRESUMEN
Chilling injury is one of the most significant limitations for low temperature storage of postharvest fruits and vegetables, causing quality deterioration and economic loss. Increasing studies indicated that methyl jasmonate (MeJA) is critical in regulating the postharvest fruit and vegetables chilling tolerance. Based on a meta-analysis, the review analyzed the action of exogenous MeJA application on the chilling index in postharvest fruit and vegetables and summarized MeJA's mechanisms for controlling postharvest chilling injury. The meta-analysis found that MeJA treatment remarkably inhibited postharvest fruit and vegetable chilling injury. Moreover, we concluded the following function mechanism of MeJA on postharvest fruit and vegetable chilling tolerance: (1) Enhancing membrane integrity and energy supply, (2) Increasing antioxidant activity, (3) Enhancing arginine pathway, (4) Enhancing sugar metabolism, (5) Regulating phenolic metabolism, (6) Activating CBF pathway, (7) Regulating HSP accumulation and expression, and (8) Crosstalk with phytohormone. Finally, we summarized the regulatory mechanisms of MeJA on postharvest fruit and vegetable biological processes at the transcriptional and post-translational levels.