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1.
Nat Commun ; 15(1): 7100, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155303

RESUMO

The identification of genes involved in replicative stress is key to understanding cancer evolution and to identify therapeutic targets. Here, we show that CDK12 prevents transcription-replication conflicts (TRCs) and the activation of cytotoxic replicative stress upon deregulation of the MYC oncogene. CDK12 was recruited at damaged genes by PARP-dependent DDR-signaling and elongation-competent RNAPII, to repress transcription. Either loss or chemical inhibition of CDK12 led to DDR-resistant transcription of damaged genes. Loss of CDK12 exacerbated TRCs in MYC-overexpressing cells and led to the accumulation of double-strand DNA breaks, occurring between co-directional early-replicating regions and transcribed genes. Overall, our data demonstrate that CDK12 protects genome integrity by repressing transcription of damaged genes, which is required for proper resolution of DSBs at oncogene-induced TRCs. This provides a rationale that explains both how CDK12 deficiency can promote tandem duplications of early-replicated regions during tumor evolution, and how CDK12 targeting can exacerbate replicative-stress in tumors.


Assuntos
Quinases Ciclina-Dependentes , Replicação do DNA , Transcrição Gênica , Humanos , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Quebras de DNA de Cadeia Dupla , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Linhagem Celular Tumoral , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Dano ao DNA
2.
Artigo em Inglês | MEDLINE | ID: mdl-38967709

RESUMO

Early-life adversity is associated with the development of internalizing and externalizing problems in children. Despite this, there is a need to understand the mechanisms linking these experiences to psychopathology, especially in clinical samples. This cross-sectional study tested emotion dysregulation as a mechanism linking early-life threat to psychopathology in a clinical sample of children with disruptive behavior problems. We also explored parental positive reinforcement as a protective factor in these pathways. A clinical sample of 606 children aged 6-12 years, referred to a mental healthcare hospital, were included. Parent-reported child threat, and parent- and teacher-reported child emotion dysregulation and psychopathology, were collected. Path analysis was used to explore the mediating effect of emotion dysregulation in the relation between threat and psychopathology. The moderating effects of parental positive reinforcement were explored through moderated-mediation analyses. Emotion dysregulation partially mediated the association between threat and both internalizing (ß = .18, P = .006) and externalizing (ß = .19, P = .002) problems. Positive reinforcement did not buffer the association between threat and emotion dysregulation (ß = .09, P = .62) or the association between emotion dysregulation and internalizing (ß = - .003, P = .20) or externalizing (ß = - .002, P = .35). Poor emotion regulation may be a transdiagnostic mechanism linking early-threat with internalizing and externalizing problems in clinic-referred children with disruptive behaviors. Factors aside from parental positive reinforcement should be explored as protective factors in these pathways, including those directly implicated in the purported mechanisms linking these factors over time.

3.
Dev Sci ; : e13517, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654410

RESUMO

There is no relationship more vital than the one a child shares with their primary caregivers early in development. Yet many children worldwide are raised in settings that lack the warmth, connection, and stimulation provided by a responsive primary caregiver. In this study, we used data from the Bucharest Early Intervention Project (BEIP), a longitudinal study of institutionally-reared and family-reared children, to test how caregiving quality during infancy is associated with average EEG power over the first 3.5 years of life in alpha, beta, and theta frequency bands, and associations with later executive function (EF) at age 8 years. The sample comprised 189 children (129 institutionally-reared; 60 family-reared) who contributed data on observed caregiving quality during infancy (baseline; average age of 22 months), resting EEG power at baseline, 30, and 42 months, and performance-based data on a series of EF tasks at 8 years. Using Bayesian estimation, observed caregiving quality at baseline was marginally linked with higher average alpha and beta power, and lower theta power, from baseline to 42 months. In turn, higher average beta power and lower average theta power were marginally associated with higher EF at 8 years. In indirect effects models, higher caregiving quality at baseline was associated with higher EF at 8 years, with a marginal indirect effect through average theta power from baseline to 42 months. Variation in the quality of the early caregiving environment may be associated with later executive function, which is partially underpinned by individual differences in brain activity during early childhood. RESEARCH HIGHLIGHTS: Examined associations between caregiving quality during infancy, brain activity during early childhood, and executive function during mid-childhood in sample of never-institutionalized and institutionally-reared children. Significant associations between higher quality caregiving during infancy and higher executive function during middle childhood. Marginal associations between caregiving quality during infancy and brain activity during early childhood. Marginal associations between brain activity during early childhood and executive function during mid-childhood.

4.
Child Abuse Negl ; : 106711, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38388324

RESUMO

BACKGROUND: Adverse Childhood Experiences (ACEs) can be passed onto future generations through complex biopsychosocial mechanisms. However, social support in caregivers who have experienced adversity may lead to adaptation. Most research on the intergenerational consequences of ACEs has focused on mental health in subsequent generations, while overlooking family functioning as an outcome. OBJECTIVE: This pre-registered study addresses this gap by examining a hypothesized association between caregiver ACEs and caregiver-perceived family functioning, and the moderating role of social support. It was expected that high levels of social support would attenuate the association between caregiver ACEs and family functioning, controlling for contemporaneous stressors in the context of the COVID-19 pandemic. PARTICIPANTS AND SETTING: Data come from a multinational non-clinical sample (n = 310). METHODS: Caregivers completed self-report measures to assess caregiver ACEs, social support, COVID stressors, and family dysfunction. RESULTS: Multiple regression analyses revealed that the ACEs-by-social support interaction was not significant. Exploratory analyses revealed a significant three-way interaction between COVID stressors, ACEs, and social support (b = 0.001, SE < 0.001, p = .008). For lower adversity, social support protected against the association between COVID stressors and family dysfunction; however, for higher adversity, social support was only protective when COVID stressors were low. CONCLUSIONS: Social support is protective against concurrent stressors during the pandemic in relation to family functioning, though this buffering depends on historical levels of adversity. Findings are interpreted through a trauma-informed lens and provide support for family-focused interventions and policies to mitigate the impact of stress on caregivers with high ACEs.

5.
JAACAP Open ; 1(3): 173-183, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38500494

RESUMO

Objective: Research on bifactor models of psychopathology in early childhood is limited to community samples with little longitudinal follow-up. We examined general and specific forms of psychopathology within 2 independent samples of preschool-aged Romanian children. Within a sample with children exposed to psychosocial deprivation, we also examined antecedents and longitudinal outcomes of the general factor. Method: One sample consisted of 350 Romanian children (mean age = 39.7 months, SD = 10.9) from an epidemiological study; the second sample consisted of 170 Romanian children (mean age = 55.6 months, SD = 1.9) exposed to severe early-life deprivation, as well as community comparison children, with longitudinal follow-up at 8 and 12 years. Psychopathology symptoms were assessed through caregiver-reported structured clinical interviews. Results: An SI-1 bifactor model of psychopathology was supported in both samples and included specific factors for externalizing, internalizing, and disturbed relatedness symptoms. In the second sample, longer duration of psychosocial deprivation and lower-quality caregiving were associated with higher scores on the general and all specific factors. Higher scores on the general factor were associated with later cognitive function, competence, and psychopathology symptoms. Considering all factors together, only the general factor explained variance in later childhood outcomes and was slightly stronger compared to a total symptom count for some, but not all, outcomes. Conclusion: General psychopathology in early childhood explains meaningful variance in child outcomes across multiple domains of functioning in later childhood. However, important questions remain regarding its clinical utility and usefulness, given complex measurement and limited explanatory power beyond the more accessible approach of a total symptom count. Clinical trial registration information: The Bucharest Early Intervention Project; https://clinicaltrials.gov/; NCT00747396.

6.
Int J Mol Sci ; 25(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38203243

RESUMO

Small extracellular vesicles (sEVs) contain microRNAs (miRNAs) which have potential to act as disease-specific biomarkers. The current study uses an established method to maintain human thyroid tissue ex vivo on a tissue-on-chip device, allowing the collection, isolation and interrogation of the sEVs released directly from thyroid tissue. sEVs were analysed for differences in miRNA levels released from benign thyroid tissue, Graves' disease tissue and papillary thyroid cancer (PTC), using miRNA sequencing and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) to identify potential biomarkers of disease. Thyroid biopsies from patients with benign tissue (n = 5), Graves' disease (n = 5) and PTC (n = 5) were perfused with medium containing sEV-depleted serum for 6 days on the tissue-on-chip device. During incubation, the effluents were collected and ultracentrifuged to isolate sEVs; miRNA was extracted and sequenced (miRNASeq). Out of the 15 samples, 14 passed the quality control and miRNASeq analysis detected significantly higher expression of miR-375-3p, miR-7-5p, miR-382-5p and miR-127-3p in the sEVs isolated from Graves' tissue compared to those from benign tissue (false discovery rate; FDR p < 0.05). Similarly, miR-375-3p and miR-7-5p were also detected at a higher level in the Graves' tissue sEVs compared to the PTC tissue sEVs (FDR p < 0.05). No significant differences were observed between miRNA in sEVs from PTC vs. those from benign tissue. These results were supported by Quantitative Reverse Transcriptase Polymerase Chain Reaction (qRT-PCR). The novel findings demonstrate that the tissue-on-chip technology is a robust method for isolating sEVs directly from the tissue of interest, which has permitted the identification of four miRNAs, with which further investigation could be used as biomarkers or therapeutic targets within thyroid disease.


Assuntos
Vesículas Extracelulares , Doença de Graves , MicroRNAs , Doenças da Glândula Tireoide , Neoplasias da Glândula Tireoide , Humanos , MicroRNAs/genética , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/genética , Controle de Qualidade , Biomarcadores , Vesículas Extracelulares/genética , Câncer Papilífero da Tireoide
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