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1.
Schizophrenia (Heidelb) ; 9(1): 46, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500637

RESUMO

Decreased 40-Hz auditory steady-state response (ASSR) is believed to reflect abnormal gamma oscillation in patients with schizophrenia (SZ). However, previous studies have reported conflicting results due to variations in inter-stimulus interval (ISI) used. In this study, we aimed to investigate the influence of varying ISI on the 40-Hz ASSR, particularly for patients with SZ and healthy controls (HCs). Twenty-four SZ patients (aged 40.8 ± 13.9 years, male: n = 11) and 21 HCs (aged 33.3 ± 11.3 years, male: n = 8) were recruited. For every participant, 40-Hz ASSRs were acquired for three different stimulus types: 500, 2000, and 3500 ms of ISIs. Two conventional ASSR measures (total power and inter-trial coherence, ITC) were calculated. Several additional ASSR measures were also analyzed: (i) ISI-dependent power; (ii) power onset slope; (iii) power centroid latency; (iv) ISI-dependent ITC; (v) ITC onset slope (500, 2000, 3500 ms); (vi) ITC centroid latency (500, 2000, 3500 ms). As ISI increased, total power and ITC increased in patients with SZ but decreased in HCs. In addition, patients with SZ showed higher ISI-dependent ITC, which was positively correlated with the psychotic symptom severity. The abnormal ITC onset slope and centroid latency for the ISI-500 ms condition were associated with cognitive speed decline in patients with SZ. Our study confirmed that the 40-Hz ASSR could be severely influenced by ISI. Furthermore, our results showed that the additional ASSR measures (ISI-dependent ITC, ITC onset slope, ITC centroid latency) could represent psychotic symptom severity or impairment in cognitive function in patients with SZ.

2.
Psychiatry Investig ; 19(10): 857-865, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36327966

RESUMO

OBJECTIVE: This study aimed to explore the relationship between childhood physical abuse and suicidal ideation considering the effects of genetic and environmental factors in patients with post-traumatic stress disorder (PTSD) by focusing on brain-derived neurotrophic factor (BDNF) polymorphism and social support, respectively. METHODS: One-hundred fourteen patients with PTSD and 94 healthy controls (HCs) were genotyped with respect to BDNF Val66Met polymorphism. All participants underwent psychological assessments. The hierarchical regression analysis and the simple slope analysis were conducted. RESULTS: As for patients with PTSD, the moderation effect of BDNF polymorphism was significant but not for social support. Specifically, the BDNF Val/Val genotype worked as a risk factor and strengthens the relationship between childhood physical abuse and suicidal ideation. As for the HCs, the significant moderation effect was found only in social support, but not for BDNF polymorphism. The relationship between childhood physical abuse and suicidal ideation was weakened for the HCs with high social support. CONCLUSION: This study demonstrated a significant BDNF genetic vulnerability for suicide in patients with PTSD who experienced childhood physical abuse. Our results suggested that social support provided a mitigating effect on the relationship between childhood physical abuse and suicidal ideation only in the HCs.

3.
Clin Psychopharmacol Neurosci ; 20(2): 292-299, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35466100

RESUMO

Objective: Patients with post-traumatic stress disorder (PTSD) showed inconsistencies in their cortisol level, an index of the hypothalamic-pituitary-adrenal axis function. This study examined the relationship between dissociation, childhood trauma, and morning cortisol levels in PTSD patients. Methods: This study included 69 (23 males and 46 females) patients and 82 (22 males and 60 females) healthy controls (HCs). Clinical assessments, including the Childhood Trauma Questionnaire (CTQ) and Peri-traumatic Dissociative Experiences Questionnaire scores, and morning cortisol levels were evaluated. The morning cortisol levels were compared between PTSD with high dissociation and low dissociation (PTSD-LD) groups. The effect of CTQ subtype on morning cortisol levels was analyzed. Results: The PTSD with high dissociation group showed significantly lower cortisol levels than that of the PTSD-LD and HC groups. A significant inverse correlation was found between cortisol levels and dissociation. A significant positive correlation was found between dissociation and physical abuse and sexual abuse scores. Morning cortisol levels showed a significant positive correlation with emotional abuse, emotional neglect, and physical neglect, respectively. There was no moderating or mediating effect of CTQ on the relationship between cortisol level and dissociation. Conclusion: These findings suggest that dissociation is a significant factor related to hypocortisolism in PTSD patients. Additionally, basal morning cortisol levels and dissociation scores were closely associated with childhood trauma.

4.
J Affect Disord ; 306: 167-173, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35314247

RESUMO

OBJECTIVES: Gene-Environment (G × E) interaction is of increasing importance in understanding the pathophysiology of posttraumatic stress disorder (PTSD). This study investigated the interaction effect of childhood traumatic experience and epigenetic methylation of brain-derived neurotrophic factor (BDNF) and a possible moderating effect of oxytocin receptor (OXTR) gene rs53576. METHODS: Ninety-nine patients with PTSD and 81 healthy controls (HCs) were recruited. Clinical assessments, including the childhood trauma questionnaire (CTQ) and posttraumatic stress disorder Checklist (PCL) were performed. BDNF methylation and OXTR genotyping (A vs. G allele) were conducted through blood sampling. A two-way multivariate analysis and a moderated regression analysis were conducted to investigate the moderating effect of the OXTR gene on the relationship between CTQ and BDNF methylation. RESULTS: As for the HC group, the interaction effect of the CTQ and OXTR genotype was significant on BDNF methylation, and the moderation model showed that CTQ and OXTR group are significant predictors of BDNF methylation. In the G-OXTR type, the high CTQ group showed a greater BDNF methylation level. As for the PTSD group, no interaction or moderation effects were found. LIMITATIONS: The present study did not control the dosage, duration of medications, and different trauma types and the assessment of childhood trauma was based on self-report. CONCLUSIONS: These results suggested that childhood traumatic experience showed a significant impact on BDNF methylation, and OXTR genes have a moderating effect on this epigenetic mechanism in people who have experienced the childhood traumatic episodes.


Assuntos
Experiências Adversas da Infância , Fator Neurotrófico Derivado do Encéfalo , Epigênese Genética , Receptores de Ocitocina , Fator Neurotrófico Derivado do Encéfalo/genética , Metilação de DNA , Humanos , Receptores de Ocitocina/genética
5.
Nucleic Acids Res ; 50(3): 1465-1483, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35037047

RESUMO

p53-binding protein 1 (53BP1) regulates the DNA double-strand break (DSB) repair pathway and maintains genomic integrity. Here we found that 53BP1 functions as a molecular scaffold for the nucleoside diphosphate kinase-mediated phosphorylation of ATP-citrate lyase (ACLY) which enhances the ACLY activity. This functional association is critical for promoting global histone acetylation and subsequent transcriptome-wide alterations in gene expression. Specifically, expression of a replication-dependent histone biogenesis factor, stem-loop binding protein (SLBP), is dependent upon 53BP1-ACLY-controlled acetylation at the SLBP promoter. This chain of regulation events carried out by 53BP1, ACLY, and SLBP is crucial for both quantitative and qualitative histone biogenesis as well as for the preservation of genomic integrity. Collectively, our findings reveal a previously unknown role for 53BP1 in coordinating replication-dependent histone biogenesis and highlight a DNA repair-independent function in the maintenance of genomic stability through a regulatory network that includes ACLY and SLBP.


Assuntos
ATP Citrato (pro-S)-Liase , Histonas , ATP Citrato (pro-S)-Liase/genética , ATP Citrato (pro-S)-Liase/metabolismo , Acetilação , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Histonas/genética , Histonas/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
6.
Cogn Res Princ Implic ; 6(1): 71, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34735659

RESUMO

Two experiments assessed how racial ambiguity and racial salience moderates the cross-race effect (CRE). In experiment 1, White and Black participants studied and identified the race of Asian, Black, Latino, and White faces that varied in ethnic typicality (high or low ET). For White participants, the CRE was larger when comparing high-ET White faces to high-ET other-race faces than low-ET other-race faces. Black participants showed a similar CRE reduction by ethnic typicality, but also showed a less prevalent CRE than White participants. Experiment 2 replicated experiment 1 procedures, but without the race identification task and only with White participants. Experiment 2 findings were comparable to experiment 1. Furthermore, experiment 2 showed a noticeably smaller CRE on Black faces than experiment 1, eliciting questions about increased racial salience amplifying the CRE. Results' general implications and the conceptual roots that indirectly link the CRE and racism will be discussed.


Assuntos
Racismo , Atenção , População Negra , Etnicidade , Humanos
7.
Front Behav Neurosci ; 15: 663052, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149370

RESUMO

The present study aimed to investigate the possible influence of childhood trauma and its interaction effect with 10 single-nucleotide polymorphisms (SNPs) of the FK506-binding protein 51 (FKBP5) gene on brain volume in non-clinical individuals. One hundred forty-four non-clinical volunteers (44 men and 100 women) were genotyped with respect to 10 variants (rs9296158, rs3800373, rs1360780, rs9470080, rs4713916, rs4713919, rs6902321, rs56311918, rs3798345, and rs9380528) of FKBP5. Participants underwent magnetic resonance imaging (MRI) scan and psychological assessments such as the childhood Trauma Questionnaire (CTQ), Hospital Anxiety and Depression Scale, rumination response scale, and quality of life assessment instrument. Individuals with the high CTQ score showed enlarged volume of the left orbitofrontal cortex (OFC) if they have childhood trauma-susceptible genotype of FKBP5 rs3800373, rs1360780, rs4713916, rs4713919, rs6902321, and rs3798345 and enlarged volume of the left middle temporal gyrus (MTG) if they have childhood trauma-susceptible genotype of FKBP5 rs3800373, rs1360780, rs4713916, and rs3798345. Among those with the childhood trauma-susceptible genotype, the left OFC and left MTG showed significant negative correlations with positive feelings about life, and the left OFC showed significant positive correlations with negative cognition. This is one of the few studies to identify the volume alteration of the left OFC and the left MTG for the FKBP5 gene-childhood trauma interaction in non-clinical individuals.

8.
Front Psychiatry ; 12: 613735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841200

RESUMO

Objective: This study examined the relationship of childhood physical abuse, posttraumatic stress disorder (PTSD), depression, and suicide in patients with PTSD through path analysis. Materials and Methods: A total of 114 patients with PTSD (36 men and 78 women) were recruited and completed psychological assessments including the Childhood Trauma Questionnaire, the scale for suicidal ideation, the clinician-administered PTSD scale for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, the PTSD checklist, and the Hospital Anxiety and Depression Scale. Structural equation modeling was used to evaluate the results. We developed a model including childhood physical abuse experience as the causal variable, suicidal ideation as a result variable, and PTSD and depression as mediation variables. PTSD symptoms were divided into four clusters [intrusion, avoidance, negative cognition and mood, and altered arousal and reactivity (hyperarousal)] to determine predictive power for suicide. Results: PTSD symptoms fully mediated the relationship between childhood physical abuse and suicidal ideation. Furthermore, PTSD symptoms fully mediated the relationship between childhood physical abuse and depression. Among the PTSD symptoms, hyperarousal was the only symptom cluster that mediated the relationship between childhood physical abuse and suicidal ideation. The symptom clusters of negative cognition and mood as well as hyperarousal mediated the relationship between childhood physical abuse and depression. Conclusions: This study presents a link between childhood physical abuse and current symptoms in patients with PTSD, and highlights specific PTSD symptom clusters (i.e., hyperarousal, negative cognition and mood) that may increase the risk for psychopathology later in life.

9.
J Clin Med ; 9(12)2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33291657

RESUMO

A precise diagnosis and a comprehensive assessment of symptom severity are important clinical issues in patients with schizophrenia (SZ). We investigated whether electroencephalography (EEG) features obtained from EEG source network analyses could be effectively applied to classify the SZ subtypes based on symptom severity. Sixty-four electrode EEG signals were recorded from 119 patients with SZ (53 males and 66 females) and 119 normal controls (NC, 51 males and 68 females) during resting-state with closed eyes. Brain network features (global and local clustering coefficient and global path length) were calculated from EEG source activities. According to positive, negative, and cognitive/disorganization symptoms, the SZ patients were divided into two groups (high and low) by positive and negative syndrome scale (PANSS). To select features for classification, we used the sequential forward selection (SFS) method. The classification accuracy was evaluated using 10 by 10-fold cross-validation with the linear discriminant analysis (LDA) classifier. The best classification accuracy was 80.66% for estimating SZ patients from the NC group. The best classification accuracy between low and high groups in positive, negative, and cognitive/disorganization symptoms were 88.10%, 75.25%, and 77.78%, respectively. The selected features well-represented the pathological brain regions of SZ. Our study suggested that resting-state EEG network features could successfully classify between SZ patients and the NC, and between low and high SZ groups in positive, negative, and cognitive/disorganization symptoms.

10.
Oncotarget ; 11(21): 2024-2025, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32523656

RESUMO

[This corrects the article DOI: 10.18632/oncotarget.10275.].

11.
Diagnostics (Basel) ; 10(5)2020 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-32375213

RESUMO

(1) Background: Prediction of treatment outcome has been one of the core objectives in clinical research of patients with major depressive disorder (MDD). This study explored the possibility of event-related potential (ERP) markers to predict antidepressant treatment outcomes among MDD patients; (2) Methods: Fifty-two patients with MDD were recruited and evaluated through Hamilton depression (HAM-D), Hamilton anxiety rating scale (HAM-A), and CORE. Patients underwent a battery of ERP measures including frontal alpha symmetry (FAA) in the low alpha band (8-10 Hz), mismatch negativity (MMN), and loudness-dependent auditory evoked potentials (LDAEP); (3) Results: During the eight weeks of study, 61% of patients achieved remission, and 77% showed successful treatment responsiveness. Patients with low FAA in F5/F6 demonstrated a significantly higher remission/response ratio and better treatment responsiveness (F (2.560, 117.755) = 3.84, p = 0.016) compared to patients with high FAA. In addition, greater FAA in F7/F8 EEG channels was significantly associated with greater melancholia scores (r = 0.34, p = 0.018). Other ERP markers lacked any significant effect; (4) Conclusions: Our results suggested low FAA (i.e., greater left frontal activity) could reflect a good treatment response in MDD patients. These findings support that FAA could be a promising index in understanding both MDD and melancholic subtype.

12.
Emerg Microbes Infect ; 9(1): 628-630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32183615

RESUMO

The African swine fever virus (ASFV) was first detected in wild boar in the Demilitarized Zone, a bordered area between South and North Korea, on 2 October 2019. Phylogenetic analyses of ASFV genes encoding p72 and CD2v indicated that the causative strain belongs to genotype II and serogroup 8, respectively, and contained additional tandem repeat sequences between the I73R and the I329L protein genes.


Assuntos
Febre Suína Africana , Asfarviridae/genética , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , Animais , Filogenia , República da Coreia , Sus scrofa , Suínos
13.
Ticks Tick Borne Dis ; 11(2): 101331, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31787559

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging zoonotic tick-borne disease caused by SFTS virus, which circulates among ticks and their host animals, including wildlife. However, few studies have examined SFTS virus infection in wildlife present in the Republic of Korea (ROK). We evaluated SFTS virus infection in tissue samples from Korean water deer (Hydropotes inermis argyropus), one of the most common wild ungulates in ROK. In this study, we evaluated tissue samples of 129 water deer carcasses collected in 2017 and detected SFTS viral RNA by conventional PCR. SFTS viral RNA was found in 3 of the 129 carcasses, showing a prevalence of 2.3 %; 2 of which were collected in Gyeongsangnam-do and 1 of which was in the Gangwon-do region. Among the 6 internal organs studied, only the spleen samples were positive. Phylogenetic analysis revealed close relationships between deer- and human-derived strains. The medium segments of the three positive cases clustered with genotype B, which is the predominant genotype in ROK. In the small segment, two cases clustered with genotype B, samples 17WD044 and 17WD065. The third sample, 17WD068 from Gangwon-do province, showed genotype A, which circulates mainly in China. The disagreement in the genotypes of the two tested segments suggests a potential reassortment between genotype A and B, resulting in genetic recombination as observed in sample 17WD068, which may be co-circulating in China and Korea. Further studies in wildlife and humans are necessary to understand the genetic characteristics of SFTS viruses circulating in ROK.


Assuntos
Cervos , Phlebovirus/fisiologia , Febre Grave com Síndrome de Trombocitopenia/veterinária , Animais , Genótipo , Phlebovirus/classificação , Phlebovirus/genética , Filogenia , Prevalência , República da Coreia/epidemiologia , Febre Grave com Síndrome de Trombocitopenia/epidemiologia , Febre Grave com Síndrome de Trombocitopenia/virologia
14.
J Microbiol ; 57(12): 1132, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31758398

RESUMO

In the article by Lee et al. published in Journal of Microbiology 2018; 56, 542-548, The KACC 19447T on 26th line of 4th paragraph in the section of 'Description of Flavobacterium parvum sp. nov.' on page 546 should be corrected in KACC 19448T. The sentence should have read: The type strain, HS916T (= KACC 19448T, = JCM 32368T), was isolated from soil polluted by sewer water in Cheonan, South Korea.We apologize for any inconvenience that this may have caused.

15.
J Microbiol ; 56(8): 542-548, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30047082

RESUMO

A novel Gram-stain-negative, motile by means of gliding, and short rod-shaped bacterium, designated HS916T, was isolated from soil polluted by sewer water in Cheonan-si, South Korea. Growth occurred at 10-35°C (optimum 30°C), pH 6.0-8.0 (optimum pH 7.0), and 0-1% sodium chloride (NaCl, w/v). Based on similarities of 16S rRNA gene sequences, strain HS916T was closely related to members of the genus Flavobacterium, exhibiting the highest sequence similarities with Flavobacterium glycines Gm-149T (96.4%), followed by F. granuli Kw05T (96.3%), F. fluminis 3R17T (96.3%), F. aquicola TMd3a3T (96.2%), and F. nitratireducens N1T (96.2%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HS916T was placed in a monophyletic cluster with F. nitratireducens N1T and F. fluminis 3R17T. The predominant fatty acids (> 5% of the total) of strain HS916T were iso-C15:0, anteiso-C15:0, iso-C15:0 3-OH, C17:1ω6с, C16:0 3-OH, iso-C17:0 3-OH, and summed feature 3 (C16:1ω7с and/or C16:1ω6с). The major polar lipids of the strain comprised phosphatidylethanolamine, unidentified aminolipids, and five unidentified lipids. The predominant respiratory quinone and the major polyamine were menaquinone-6 (MK-6) and symhomospermidine, respectively. The DNA G + C content of strain HS916T was 34.9 mol%. Based on polyphasic analyses, strain HS916T represents a novel species belonging to the genus Flavobacterium, for which the name Flavobacterium parvum sp. nov. is proposed. The type strain is HS916T (= KACC 19448T = JCM 32368T).


Assuntos
Flavobacterium/classificação , Flavobacterium/isolamento & purificação , Esgotos/microbiologia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Flavobacterium/genética , Flavobacterium/fisiologia , Concentração de Íons de Hidrogênio , Coreia (Geográfico) , Locomoção , Fosfolipídeos/análise , Filogenia , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Temperatura , Vitamina K 2/análise
16.
BMC Cancer ; 18(1): 729, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986691

RESUMO

BACKGROUND: A relatively high proportion of patients diagnosed with primary CNS lymphoma will experience recurrent disease, yet therapy options are limited in salvage therapy. This is the first study to evaluate a bendamustine-based combination regimen for the treatment of relapsed/refractory PCNSL and to characterize bendamustine pharmacokinetics in the human CSF. METHODS: Patients received bendamustine 75 mg/m2 for two days as part of R-B(O)AD administered intravenously every 4 weeks for up to 4 cycles. Response and adverse events of the regimen were assessed. A sparse sampling strategy and population based modeling approach was utilized for evaluation of plasma and CSF levels of bendamustine. RESULTS: Ten patients were enrolled into study of whom 70% were of refractory disease and with high IELSG prognostic risk scores. The ORR of R-BOAD was 50% (95% CI, 0.24 to 0.76) with one patient achieving CR and four PR. Primary toxicity of the regimen was reversible myelosuppression, mostly grade 3 or 4 neutropenia. The Cmax mean for plasma and CSF were 2669 ng/mL and 0.397 ng/mL, respectively, and patients with response at deep tumor sites displayed higher trends in peak exposure. Pharmacokinetic data was best described by a four-compartment model with first-order elimination of drug from central plasma and CSF compartments. CONCLUSIONS: R-BOAD is an effective salvage option for PCNSL, but with significant hematologic toxicity. Bendamustine CSF levels are minimal; however correspond to plasma exposure and response. TRIAL REGISTRATION: ClinicalTrials.gov NCT03392714 ; retrospectively registered January 8, 2018.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cloridrato de Bendamustina/administração & dosagem , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma/tratamento farmacológico , Terapia de Salvação , Adulto , Idoso , Cloridrato de Bendamustina/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
17.
Cell Cycle ; 16(16): 1534-1546, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28745977

RESUMO

In previous studies, we observed that Zeta-chain-associated protein kinase 70 (Zap70) regulates spindle assembly and chromosome alignment in mouse oocyte and that Ran binding protein 2 (RanBP2) is a highly associated gene with Zap70 based on a microarray analysis. Because RanBP2 is related to nuclear envelope breakdown (NEBD) during mitosis, the aim of the present study was to elucidate the molecular mechanism of Zap70 with respect to RanBP2 in the germinal vesicle breakdown (GVBD) of oocytes. Results indicated that RanBP2 expression was regulated by Zap70 and that depletion of RanBP2 using RanBP2 RNAi manifested comparable phenotypes to those observed in Zap70 RNAi-treated oocytes, which presented faster processing of GVBD. Additionally, Zap70 RNAi-treated oocytes showed faster meiotic resumption with premature activation of maturation-promoting factor (MPF), premature division of chromosomes at approximately 6-8 h and more rapid degradation of securin. In conclusion, we report that Zap70 is a crucial factor for controlling the exact timing of meiotic progression in mouse oocytes.


Assuntos
Meiose , Chaperonas Moleculares/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Proteína-Tirosina Quinase ZAP-70/metabolismo , Animais , Diferenciação Celular , Segregação de Cromossomos , Cromossomos de Mamíferos/metabolismo , Feminino , Mesotelina , Camundongos Endogâmicos ICR , Modelos Biológicos , Interferência de RNA , Securina/metabolismo , Fatores de Tempo
18.
Oncotarget ; 7(29): 45976-45994, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27351285

RESUMO

Inflammation is a potent inducer of tumorigenesis. Increased DNA damage or loss of genome integrity is thought to be one of the mechanisms linking inflammation and cancer development. It has been suggested that NF-κB-induced microRNA-146 (miR146a) may be a mediator of the inflammatory response. Based on our initial observation that miR146a overexpression strongly increases DNA damage, we investigated its potential role as a modulator of DNA repair. Here, we demonstrate that FANCM, a component in the Fanconi Anemia pathway, is a novel target of miR146a. miR146a suppressed FANCM expression by directly binding to the 3' untranslated region of the gene. miR146a-induced downregulation of FANCM was associated with inhibition of FANCD2 monoubiquitination, reduced DNA homologous recombination repair and checkpoint response, failed recovery from replication stress, and increased cellular sensitivity to cisplatin. These phenotypes were recapitulated when miR146a expression was induced by overexpressing the NF-κB subunit p65/RelA or Helicobacter pylori infection in a human gastric cell line; the phenotypes were effectively reversed with an anti-miR146a antagomir. These results suggest that undesired inflammation events caused by a pathogen or over-induction of miR146a can impair genome integrity via suppression of FANCM.


Assuntos
DNA Helicases/biossíntese , Regulação da Expressão Gênica/genética , MicroRNAs/genética , Linhagem Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Dano ao DNA/fisiologia , DNA Helicases/genética , Reparo do DNA/fisiologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia
19.
Reproduction ; 151(4): 369-78, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762402

RESUMO

Mouse oocytes begin to mature in vitro once liberated from ovarian follicles. Previously, we showed that oocyte-specific homeobox 4 (Obox4) is critical for maintaining the intact nuclear membrane of the germinal vesicle (GV) in oocytes and for completing meiosis at the metaphase I-II (MI-MII) transition. This study further examines the molecular mechanisms of OBOX4 in regulating GV nuclear membrane breakdown. Maturation-promoting factor (MPF) and MAPK are normally inactive in GV stage oocytes but were activated prematurely in arrested GV stage oocytes by 3-isobutyl-1-metyl-xanthine (IBMX) in vitro after Obox4 RNA interference (RNAi). Furthermore, signal transducer and activator of transcription 3 (STAT3) was significantly activated by Obox4 RNAi. We confirmed that this Obox4 RNAi-induced premature STAT3 and MPF/MAPK activation at the GV stage provoked subsequent GV breakdown (GVBD) despite the opposing force of high cAMP in the IBMX-supplemented medium to maintain intact GV. When cumulus-oocyte complexes were exposed to interferon α (IFNA), a STAT3 activator, oocytes matured and cumulus cells expanded to resume nuclear maturation in IBMX-supplemented medium, suggesting that STAT3 activation is sufficient for stimulating the continuation of meiosis. Using Stattic, a specific STAT3 inhibitor, we confirmed that GVBD involves STAT3 activation in Obox4-silenced oocytes. Based on these findings, we concluded that i) Obox4 is an important upstream regulator of MPF/MAPK and STAT3 signaling, and ii) Obox4 is a key regulator of the GV arrest mechanism in oocytes.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Inativação Gênica , Proteínas de Homeodomínio/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Membrana Nuclear/metabolismo , Oócitos/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas , Feminino , Imunofluorescência , Proteínas Ligadas por GPI/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Técnicas Imunoenzimáticas , Meiose/fisiologia , Mesotelina , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Oócitos/citologia , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Fosforilação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética
20.
Cancer Res ; 75(7): 1298-310, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25627978

RESUMO

MDC1 is critical component of the DNA damage response (DDR) machinery and orchestrates the ensuring assembly of the DDR protein at the DNA damage sites, and therefore loss of MDC1 results in genomic instability and tumorigenicity. However, the molecular mechanisms controlling MDC1 expression are currently unknown. Here, we show that miR-22 inhibits MDC1 translation via direct binding to its 3' untranslated region, leading to impaired DNA damage repair and genomic instability. We demonstrated that activated Akt1 and senescence hinder DDR function of MDC1 by upregulating endogenous miR-22. After overexpression of constitutively active Akt1, homologous recombination was inhibited by miR-22-mediated MDC1 repression. In addition, during replicative senescence and stress-induced premature senescence, MDC1 was downregulated by upregulating miR-22 and thereby accumulating DNA damage. Our results demonstrate a central role of miR-22 in the physiologic regulation of MDC1-dependent DDR and suggest a molecular mechanism for how aberrant Akt1 activation and senescence lead to increased genomic instability, fostering an environment that promotes tumorigenesis.


Assuntos
Reparo do DNA , Instabilidade Genômica , MicroRNAs/fisiologia , Proteínas Nucleares/genética , Transativadores/genética , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Idoso , Animais , Proteínas de Ciclo Celular , Senescência Celular , Dano ao DNA , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Camundongos , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Transativadores/metabolismo , Adulto Jovem
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