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1.
Cell ; 150(3): 563-74, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22863009

RESUMO

Myc oncoproteins directly regulate transcription by binding to target genes, yet this only explains a fraction of the genes affected by Myc. mRNA turnover is controlled via AU-binding proteins (AUBPs) that recognize AU-rich elements (AREs) found within many transcripts. Analyses of precancerous and malignant Myc-expressing B cells revealed that Myc regulates hundreds of ARE-containing (ARED) genes and select AUBPs. Notably, Myc directly suppresses transcription of Tristetraprolin (TTP/ZFP36), an mRNA-destabilizing AUBP, and this circuit is also operational during B lymphopoiesis and IL7 signaling. Importantly, TTP suppression is a hallmark of cancers with MYC involvement, and restoring TTP impairs Myc-induced lymphomagenesis and abolishes maintenance of the malignant state. Further, there is a selection for TTP loss in malignancy; thus, TTP functions as a tumor suppressor. Finally, Myc/TTP-directed control of select cancer-associated ARED genes is disabled during lymphomagenesis. Thus, Myc targets AUBPs to regulate ARED genes that control tumorigenesis.


Assuntos
Genes Supressores de Tumor , Linfoma de Células B/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Tristetraprolina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estabilidade de RNA , RNA Mensageiro/química
2.
Hum Brain Mapp ; 45(1): e26553, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224541

RESUMO

22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It is associated with a significant impact on brain structure, including prominent reductions in gray matter volume (GMV), and neuropsychiatric manifestations, including cognitive impairment and psychosis. It is unclear whether GMV alterations in 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 with 22q11DS: 51% females, mean age [SD] 18.2 [9.2]; and 313 typically developing [TD] controls: 46% females, mean age 18.0 [8.6]) from 13 datasets were included in the present study. We segmented structural T1-weighted brain MRI scans and extracted GMV images, which were then utilized in a novel source-based morphometry (SBM) pipeline (SS-Detect) to generate structural brain patterns (SBPs) that capture co-varying GMV. We investigated the impact of the 22q11.2 deletion, deletion size, intelligence quotient, and psychosis on the SBPs. Seventeen GMV-SBPs were derived, which provided spatial patterns of GMV covariance associated with a quantitative metric (i.e., loading score) for analysis. Patterns of topographically widespread differences in GMV covariance, including the cerebellum, discriminated individuals with 22q11DS from healthy controls. The spatial extents of the SBPs that revealed disparities between individuals with 22q11DS and controls were consistent with the findings of the univariate voxel-based morphometry analysis. Larger deletion size was associated with significantly lower GMV in frontal and occipital SBPs; however, history of psychosis did not show a strong relationship with these covariance patterns. 22q11DS is associated with distinct structural abnormalities captured by topographical GMV covariance patterns that include the cerebellum. Findings indicate that structural anomalies in 22q11DS manifest in a nonrandom manner and in distinct covarying anatomical patterns, rather than a diffuse global process. These SBP abnormalities converge with previously reported cortical surface area abnormalities, suggesting disturbances of early neurodevelopment as the most likely underlying mechanism.


Assuntos
Síndrome de DiGeorge , Transtornos Psicóticos , Feminino , Humanos , Adolescente , Masculino , Síndrome de DiGeorge/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Transtornos Psicóticos/complicações , Substância Cinzenta/diagnóstico por imagem
3.
Mol Psychiatry ; 28(10): 4342-4352, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495890

RESUMO

22q11.2 deletion syndrome, or 22q11.2DS, is a genetic syndrome associated with high rates of schizophrenia and autism spectrum disorders, in addition to widespread structural and functional abnormalities throughout the brain. Experimental animal models have identified neuronal connectivity deficits, e.g., decreased axonal length and complexity of axonal branching, as a primary mechanism underlying atypical brain development in 22q11.2DS. However, it is still unclear whether deficits in axonal morphology can also be observed in people with 22q11.2DS. Here, we provide an unparalleled in vivo characterization of white matter microstructure in participants with 22q11.2DS (12-15 years) and those undergoing typical development (8-18 years) using a customized magnetic resonance imaging scanner which is sensitive to axonal morphology. A rich array of diffusion MRI metrics are extracted to present microstructural profiles of typical and atypical white matter development, and provide new evidence of connectivity differences in individuals with 22q11.2DS. A recent, large-scale consortium study of 22q11.2DS identified higher diffusion anisotropy and reduced overall diffusion mobility of water as hallmark microstructural alterations of white matter in individuals across a wide age range (6-52 years). We observed similar findings across the white matter tracts included in this study, in addition to identifying deficits in axonal morphology. This, in combination with reduced tract volume measurements, supports the hypothesis that abnormal microstructural connectivity in 22q11.2DS may be mediated by densely packed axons with disproportionately small diameters. Our findings provide insight into the in vivo white matter phenotype of 22q11.2DS, and promote the continued investigation of shared features in neurodevelopmental and psychiatric disorders.


Assuntos
Síndrome de DiGeorge , Esquizofrenia , Substância Branca , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Síndrome de DiGeorge/genética , Imagem de Tensor de Difusão/métodos , Encéfalo
4.
Hum Brain Mapp ; 43(1): 300-328, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33615640

RESUMO

The Enhancing NeuroImaging Genetics through Meta-Analysis copy number variant (ENIGMA-CNV) and 22q11.2 Deletion Syndrome Working Groups (22q-ENIGMA WGs) were created to gain insight into the involvement of genetic factors in human brain development and related cognitive, psychiatric and behavioral manifestations. To that end, the ENIGMA-CNV WG has collated CNV and magnetic resonance imaging (MRI) data from ~49,000 individuals across 38 global research sites, yielding one of the largest studies to date on the effects of CNVs on brain structures in the general population. The 22q-ENIGMA WG includes 12 international research centers that assessed over 533 individuals with a confirmed 22q11.2 deletion syndrome, 40 with 22q11.2 duplications, and 333 typically developing controls, creating the largest-ever 22q11.2 CNV neuroimaging data set. In this review, we outline the ENIGMA infrastructure and procedures for multi-site analysis of CNVs and MRI data. So far, ENIGMA has identified effects of the 22q11.2, 16p11.2 distal, 15q11.2, and 1q21.1 distal CNVs on subcortical and cortical brain structures. Each CNV is associated with differences in cognitive, neurodevelopmental and neuropsychiatric traits, with characteristic patterns of brain structural abnormalities. Evidence of gene-dosage effects on distinct brain regions also emerged, providing further insight into genotype-phenotype relationships. Taken together, these results offer a more comprehensive picture of molecular mechanisms involved in typical and atypical brain development. This "genotype-first" approach also contributes to our understanding of the etiopathogenesis of brain disorders. Finally, we outline future directions to better understand effects of CNVs on brain structure and behavior.


Assuntos
Encéfalo , Variações do Número de Cópias de DNA , Imageamento por Ressonância Magnética , Transtornos Mentais , Transtornos do Neurodesenvolvimento , Neuroimagem , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Humanos , Transtornos Mentais/diagnóstico por imagem , Transtornos Mentais/genética , Transtornos Mentais/patologia , Estudos Multicêntricos como Assunto , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/patologia
5.
Mol Psychiatry ; 25(11): 2818-2831, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31358905

RESUMO

22q11.2 deletion syndrome (22q11DS)-a neurodevelopmental condition caused by a hemizygous deletion on chromosome 22-is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples and variable methods have led to contradictory results. Here we present the largest study ever conducted of dMRI-derived measures of WM microstructure in 22q11DS (334 22q11.2 deletion carriers and 260 healthy age- and sex-matched controls; age range 6-52 years). Using harmonization protocols developed by the ENIGMA-DTI working group, we identified widespread reductions in mean, axial and radial diffusivities in 22q11DS, most pronounced in regions with major cortico-cortical and cortico-thalamic fibers: the corona radiata, corpus callosum, superior longitudinal fasciculus, posterior thalamic radiations, and sagittal stratum (Cohen's d's ranging from -0.9 to -1.3). Only the posterior limb of the internal capsule (IC), comprised primarily of corticofugal fibers, showed higher axial diffusivity in 22q11DS. 22q11DS patients showed higher mean fractional anisotropy (FA) in callosal and projection fibers (IC and corona radiata) relative to controls, but lower FA than controls in regions with predominantly association fibers. Psychotic illness in 22q11DS was associated with more substantial diffusivity reductions in multiple regions. Overall, these findings indicate large effects of the 22q11.2 deletion on WM microstructure, especially in major cortico-cortical connections. Taken together with findings from animal models, this pattern of abnormalities may reflect disrupted neurogenesis of projection neurons in outer cortical layers.


Assuntos
Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/patologia , Imagem de Difusão por Ressonância Magnética , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adolescente , Adulto , Anisotropia , Criança , Síndrome de DiGeorge/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Mol Psychiatry ; 25(8): 1822-1834, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-29895892

RESUMO

The 22q11.2 deletion (22q11DS) is a common chromosomal microdeletion and a potent risk factor for psychotic illness. Prior studies reported widespread cortical changes in 22q11DS, but were generally underpowered to characterize neuroanatomic abnormalities associated with psychosis in 22q11DS, and/or neuroanatomic effects of variability in deletion size. To address these issues, we developed the ENIGMA (Enhancing Neuro Imaging Genetics Through Meta-Analysis) 22q11.2 Working Group, representing the largest analysis of brain structural alterations in 22q11DS to date. The imaging data were collected from 10 centers worldwide, including 474 subjects with 22q11DS (age = 18.2 ± 8.6; 46.9% female) and 315 typically developing, matched controls (age = 18.0 ± 9.2; 45.9% female). Compared to controls, 22q11DS individuals showed thicker cortical gray matter overall (left/right hemispheres: Cohen's d = 0.61/0.65), but focal thickness reduction in temporal and cingulate cortex. Cortical surface area (SA), however, showed pervasive reductions in 22q11DS (left/right hemispheres: d = -1.01/-1.02). 22q11DS cases vs. controls were classified with 93.8% accuracy based on these neuroanatomic patterns. Comparison of 22q11DS-psychosis to idiopathic schizophrenia (ENIGMA-Schizophrenia Working Group) revealed significant convergence of affected brain regions, particularly in fronto-temporal cortex. Finally, cortical SA was significantly greater in 22q11DS cases with smaller 1.5 Mb deletions, relative to those with typical 3 Mb deletions. We found a robust neuroanatomic signature of 22q11DS, and the first evidence that deletion size impacts brain structure. Psychotic illness in this highly penetrant deletion was associated with similar neuroanatomic abnormalities to idiopathic schizophrenia. These consistent cross-site findings highlight the homogeneity of this single genetic etiology, and support the suitability of 22q11DS as a biological model of schizophrenia.


Assuntos
Córtex Cerebral/patologia , Deleção Cromossômica , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/patologia , Adolescente , Adulto , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos Psicóticos/genética , Adulto Jovem
7.
Br J Psychiatry ; 211(4): 223-230, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28882829

RESUMO

Background22q11.2 deletion syndrome (22q11.2DS) is associated with a high risk of childhood as well as adult psychiatric disorders, in particular schizophrenia. Childhood cognitive deterioration in 22q11.2DS has previously been reported, but only in studies lacking a control sample.AimsTo compare cognitive trajectories in children with 22q11.2DS and unaffected control siblings.MethodA longitudinal study of neurocognitive functioning (IQ, executive function, processing speed and attention) was conducted in children with 22q11.2DS (n = 75, mean age time 1 (T1) 9.9, time 2 (T2) 12.5) and control siblings (n = 33, mean age T1 10.6, T2 13.4).ResultsChildren with 22q11.2DS exhibited deficits in all cognitive domains. However, mean scores did not indicate deterioration. When individual trajectories were examined, some participants showed significant decline over time, but the prevalence was similar for 22q11.2DS and control siblings. Findings are more likely to reflect normal developmental fluctuation than a 22q11.2DS-specific abnormality.ConclusionsChildhood cognitive deterioration is not associated with 22q11.2DS. Contrary to previous suggestions, we believe it is premature to recommend repeated monitoring of cognitive function for identifying individual children with 22q11.2DS at high risk of developing schizophrenia.


Assuntos
Desenvolvimento Infantil , Transtornos Cognitivos/psicologia , Síndrome de DiGeorge/psicologia , Adolescente , Estudos de Casos e Controles , Criança , Transtornos Cognitivos/complicações , Síndrome de DiGeorge/complicações , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos
8.
Psychooncology ; 25(3): 300-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26211449

RESUMO

OBJECTIVE: The Cancer Stories Study aimed to identify the factors that empower people who have experienced cancer. More specifically the project sought to explore the coping and support mechanisms people adopted to help understand and manage their cancer experience. METHODS: A participatory research approach involved researchers and consumers working in partnership on the project. This research team agreed on a qualitative method that focused on cancer survivors' personal stories. Semi-structured interviews were conducted with 38 cancer survivors in the lower half of the North Island, New Zealand (NZ). Generic qualitative analysis methods were employed including the recording, transcribing and thematic coding of interview narratives. RESULTS: Seven distinct themes were classified under the overarching theme of empowerment: attitude, change, family/whanau and friends, healthcare professionals and services, sources of support, employment and tangata whenua (NZ's indigenous peoples). The unique needs of each individual were strongly emphasised throughout all the themes indicating a 'one-size-fits-all' approach has its limitations. The need for improvements in communication, cultural and spiritual care was highlighted by many participants. CONCLUSIONS: It is anticipated that this project will contribute to a greater understanding of the factors that might empower people in their cancer journey. An empowerment lens, that asks how those affected by cancer may be further enabled at an individual, family/whanau, employer and healthcare professional level may be useful in assisting people navigate and manage their cancer.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Narração , Neoplasias/psicologia , Sobreviventes/psicologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Comunicação , Pesquisa Participativa Baseada na Comunidade , Depressão/epidemiologia , Emprego , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Neoplasias/etnologia , Nova Zelândia/epidemiologia , Prevalência , Pesquisa Qualitativa , Apoio Social
9.
Br J Psychiatry ; 204(3): 171-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24590970

RESUMO

There is increasing concern that a reliance on the descriptive, syndrome-based diagnostic criteria of ICD and DSM is impeding progress in research. The USA's major funder of psychiatric research, the National Institute of Mental Health (NIMH), have stated their intention to encourage more research across diagnostic categories using a novel framework based on findings in neuroscience.


Assuntos
Transtornos Mentais/diagnóstico , National Institute of Mental Health (U.S.) , Projetos de Pesquisa/normas , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Classificação Internacional de Doenças , Estados Unidos
10.
Neuropsychopharmacology ; 49(2): 368-376, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37402765

RESUMO

Although many genetic risk factors for psychiatric and neurodevelopmental disorders have been identified, the neurobiological route from genetic risk to neuropsychiatric outcome remains unclear. 22q11.2 deletion syndrome (22q11.2DS) is a copy number variant (CNV) syndrome associated with high rates of neurodevelopmental and psychiatric disorders including autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD) and schizophrenia. Alterations in neural integration and cortical connectivity have been linked to the spectrum of neuropsychiatric disorders seen in 22q11.2DS and may be a mechanism by which the CNV acts to increase risk. In this study, magnetoencephalography (MEG) was used to investigate electrophysiological markers of local and global network function in 34 children with 22q11.2DS and 25 controls aged 10-17 years old. Resting-state oscillatory activity and functional connectivity across six frequency bands were compared between groups. Regression analyses were used to explore the relationships between these measures, neurodevelopmental symptoms and IQ. Children with 22q11.2DS had altered network activity and connectivity in high and low frequency bands, reflecting modified local and long-range cortical circuitry. Alpha and theta band connectivity were negatively associated with ASD symptoms while frontal high frequency (gamma band) activity was positively associated with ASD symptoms. Alpha band activity was positively associated with cognitive ability. These findings suggest that haploinsufficiency at the 22q11.2 locus impacts short and long-range cortical circuits, which could be a mechanism underlying neurodevelopmental and psychiatric vulnerability in this high-risk group.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Síndrome de DiGeorge , Criança , Humanos , Adolescente , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/complicações , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/genética , Cognição , Fatores de Risco
11.
Biol Psychiatry ; 95(2): 147-160, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37661008

RESUMO

BACKGROUND: Carriers of the 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants exhibit regional and global brain differences compared with noncarriers. However, interpreting regional differences is challenging if a global difference drives the regional brain differences. Intraindividual variability measures can be used to test for regional differences beyond global differences in brain structure. METHODS: Magnetic resonance imaging data were used to obtain regional brain values for 1q21.1 distal deletion (n = 30) and duplication (n = 27) and 15q11.2 BP1-BP2 deletion (n = 170) and duplication (n = 243) carriers and matched noncarriers (n = 2350). Regional intra-deviation scores, i.e., the standardized difference between an individual's regional difference and global difference, were used to test for regional differences that diverge from the global difference. RESULTS: For the 1q21.1 distal deletion carriers, cortical surface area for regions in the medial visual cortex, posterior cingulate, and temporal pole differed less and regions in the prefrontal and superior temporal cortex differed more than the global difference in cortical surface area. For the 15q11.2 BP1-BP2 deletion carriers, cortical thickness in regions in the medial visual cortex, auditory cortex, and temporal pole differed less and the prefrontal and somatosensory cortex differed more than the global difference in cortical thickness. CONCLUSIONS: We find evidence for regional effects beyond differences in global brain measures in 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants. The results provide new insight into brain profiling of the 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants, with the potential to increase understanding of the mechanisms involved in altered neurodevelopment.


Assuntos
Anormalidades Múltiplas , Deleção Cromossômica , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Cromossomos Humanos Par 15 , Variações do Número de Cópias de DNA
12.
Schizophr Res ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37919212

RESUMO

Mental health and neurodevelopmental disorders are highly heritable and can affect morbidity and mortality. A large, growing body of evidence has implicated both common and rare variation in the risk of these disorders. Testing for rare variants, such as copy number variants, has been available in clinical practice for some time in the context of developmental disorders. However, until recently, individuals with mental health and neurodevelopmental disorders in the UK have not tended to access genetic counselling and testing. Here, we describe the development of the All Wales Psychiatric Genomics Service, a collaborative effort between psychiatric and clinical genetics services and the first of its kind in the UK. We provide an overview of the structure and function of the service, our referral criteria, a summary of the 40 referrals we have received to date and our future plans.

13.
Blood ; 116(9): 1498-505, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-20519624

RESUMO

Myc oncoproteins promote continuous cell growth, in part by controlling the transcription of key cell cycle regulators. Here, we report that c-Myc regulates the expression of Aurora A and B kinases (Aurka and Aurkb), and that Aurka and Aurkb transcripts and protein levels are highly elevated in Myc-driven B-cell lymphomas in both mice and humans. The induction of Aurka by Myc is transcriptional and is directly mediated via E-boxes, whereas Aurkb is regulated indirectly. Blocking Aurka/b kinase activity with a selective Aurora kinase inhibitor triggers transient mitotic arrest, polyploidization, and apoptosis of Myc-induced lymphomas. These phenotypes are selectively bypassed by a kinase inhibitor-resistant Aurkb mutant, demonstrating that Aurkb is the primary therapeutic target in the context of Myc. Importantly, apoptosis provoked by Aurk inhibition was p53 independent, suggesting that Aurka/Aurkb inhibitors will show efficacy in treating primary or relapsed malignancies having Myc involvement and/or loss of p53 function.


Assuntos
Linfócitos B/patologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Linfoma de Células B/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Apoptose , Aurora Quinase A , Aurora Quinase B , Aurora Quinases , Linfócitos B/metabolismo , Células 3T3 BALB , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Proliferação de Células , Transformação Celular Neoplásica , Células Cultivadas , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Perfilação da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Luciferases/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
14.
Neurooncol Adv ; 4(1): vdac072, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855490

RESUMO

Background: Neurofibromatosis type 2 (NF2) is an autosomal dominant genetic disease characterized by development of schwannomas on the VIIIth (vestibular) cranial nerves. Bromodomain and extra-terminal domain (BET) proteins regulate gene transcription and their activity is required in a variety of cancers including malignant peripheral nerve sheath tumors. The use of BET inhibitors as a therapeutic option to treat NF2 schwannomas has not been explored and is the focus of this study. Methods: A panel of normal and NF2-null Schwann and schwannoma cell lines were used to characterize the impact of the BET inhibitor JQ1 in vitro and in vivo. The mechanism of action was explored by chromatin immunoprecipitation of the BET BRD4, phospho-kinase arrays and immunohistochemistry (IHC) of BRD4 in vestibular schwannomas. Results: JQ1 inhibited proliferation of NF2-null schwannoma and Schwann cell lines in vitro and in vivo. Further, loss of NF2 by CRISPR deletion or siRNA knockdown increased sensitivity of cells to JQ1. Loss of function experiments identified BRD4, and to a lesser extent BRD2, as BET family members mediating the majority of JQ1 effects. IHC demonstrated elevated levels of BRD4 protein in human vestibular schwannomas. Analysis of signaling pathways effected by JQ1 treatment suggests that the effects of JQ1 treatment are mediated, at least in part, via inhibition of PI3K/Akt signaling. Conclusions: NF2-deficient Schwann and schwannoma cells are sensitive to BET inhibition, primarily mediated by BRD4, which is overexpressed in human vestibular schwannomas. Our results suggest BRD4 regulates PI3K signaling and likely impedes NF2 schwannoma growth via this inhibition. These findings implicate BET inhibition as a therapeutic option for NF2-deficient schwannomas.

15.
Nat Comput Sci ; 1: 598-606, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35865756

RESUMO

Most diffusion magnetic resonance imaging studies of disease rely on statistical comparisons between large groups of patients and healthy participants to infer altered tissue states in the brain; however, clinical heterogeneity can greatly challenge their discriminative power. There is currently an unmet need to move away from the current approach of group-wise comparisons to methods with the sensitivity to detect altered tissue states at the individual level. This would ultimately enable the early detection and interpretation of microstructural abnormalities in individual patients, an important step towards personalized medicine in translational imaging. To this end, Detect was developed to advance diffusion magnetic resonance imaging tractometry towards single-patient analysis. By operating on the manifold of white-matter pathways and learning normative microstructural features, our framework captures idiosyncrasies in patterns along white-matter pathways. Our approach paves the way from traditional group-based comparisons to true personalized radiology, taking microstructural imaging from the bench to the bedside.

16.
Am J Psychiatry ; 178(1): 77-86, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33384013

RESUMO

OBJECTIVE: Certain copy number variants (CNVs) greatly increase the risk of autism. The authors conducted a genetics-first study to investigate whether heterogeneity in the clinical presentation of autism is underpinned by specific genotype-phenotype relationships. METHODS: This international study included 547 individuals (mean age, 12.3 years [SD=4.2], 54% male) who were ascertained on the basis of having a genetic diagnosis of a rare CNV associated with high risk of autism (82 16p11.2 deletion carriers, 50 16p11.2 duplication carriers, 370 22q11.2 deletion carriers, and 45 22q11.2 duplication carriers), as well as 2,027 individuals (mean age, 9.1 years [SD=4.9], 86% male) with autism of heterogeneous etiology. Assessments included the Autism Diagnostic Interview-Revised and IQ testing. RESULTS: The four genetic variant groups differed in autism symptom severity, autism subdomain profile, and IQ profile. However, substantial variability was observed in phenotypic outcome in individual genetic variant groups (74%-97% of the variance, depending on the trait), whereas variability between groups was low (1%-21%, depending on the trait). CNV carriers who met autism criteria were compared with individuals with heterogeneous autism, and a range of profile differences were identified. When clinical cutoff scores were applied, 54% of individuals with one of the four CNVs who did not meet full autism diagnostic criteria had elevated levels of autistic traits. CONCLUSIONS: Many CNV carriers do not meet full diagnostic criteria for autism but nevertheless meet clinical cutoffs for autistic traits. Although profile differences between variants were observed, there is considerable variability in clinical symptoms in the same variant.


Assuntos
Transtorno Autístico/genética , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Transtorno Autístico/diagnóstico , Transtorno Autístico/epidemiologia , Criança , Deleção de Genes , Estudos de Associação Genética , Heterozigoto , Humanos , Entrevista Psicológica , Masculino , Prevalência , Fatores de Risco , Índice de Gravidade de Doença
17.
Transl Psychiatry ; 11(1): 182, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753722

RESUMO

Low-frequency 1q21.1 distal deletion and duplication copy number variant (CNV) carriers are predisposed to multiple neurodevelopmental disorders, including schizophrenia, autism and intellectual disability. Human carriers display a high prevalence of micro- and macrocephaly in deletion and duplication carriers, respectively. The underlying brain structural diversity remains largely unknown. We systematically called CNVs in 38 cohorts from the large-scale ENIGMA-CNV collaboration and the UK Biobank and identified 28 1q21.1 distal deletion and 22 duplication carriers and 37,088 non-carriers (48% male) derived from 15 distinct magnetic resonance imaging scanner sites. With standardized methods, we compared subcortical and cortical brain measures (all) and cognitive performance (UK Biobank only) between carrier groups also testing for mediation of brain structure on cognition. We identified positive dosage effects of copy number on intracranial volume (ICV) and total cortical surface area, with the largest effects in frontal and cingulate cortices, and negative dosage effects on caudate and hippocampal volumes. The carriers displayed distinct cognitive deficit profiles in cognitive tasks from the UK Biobank with intermediate decreases in duplication carriers and somewhat larger in deletion carriers-the latter potentially mediated by ICV or cortical surface area. These results shed light on pathobiological mechanisms of neurodevelopmental disorders, by demonstrating gene dose effect on specific brain structures and effect on cognitive function.


Assuntos
Variações do Número de Cópias de DNA , Esquizofrenia , Encéfalo/diagnóstico por imagem , Deleção Cromossômica , Cognição , Feminino , Humanos , Masculino , Esquizofrenia/genética
18.
Cancer Res ; 80(12): 2512-2522, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32409309

RESUMO

The Hippo pathway regulates cell proliferation and organ size through control of the transcriptional regulators YAP (yes-associated protein) and TAZ. Upon extracellular stimuli such as cell-cell contact, the pathway negatively regulates YAP through cytoplasmic sequestration. Under conditions of low cell density, YAP is nuclear and associates with enhancer regions and gene promoters. YAP is mainly described as a transcriptional activator of genes involved in cell proliferation and survival. Using a genome-wide approach, we show here that, in addition to its known function as a transcriptional activator, YAP functions as a transcriptional repressor by interacting with the multifunctional transcription factor Yin Yang 1 (YY1) and Polycomb repressive complex member enhancer of zeste homologue 2 (EZH2). YAP colocalized with YY1 and EZH2 on the genome to transcriptionally repress a broad network of genes mediating a host of cellular functions, including repression of the cell-cycle kinase inhibitor p27, whose role is to functionally promote contact inhibition. This work unveils a broad and underappreciated aspect of YAP nuclear function as a transcriptional repressor and highlights how loss of contact inhibition in cancer is mediated in part through YAP repressive function. SIGNIFICANCE: This study provides new insights into YAP as a broad transcriptional repressor of key regulators of the cell cycle, in turn influencing contact inhibition and tumorigenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ciclo Celular/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Fator de Transcrição YY1/metabolismo , Animais , Carcinogênese/genética , Fracionamento Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , Camundongos , Neoplasias/patologia , Regiões Promotoras Genéticas/genética , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP
19.
Transl Psychiatry ; 10(1): 324, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958742

RESUMO

Rare copy number variants associated with increased risk for neurodevelopmental and psychiatric disorders (referred to as ND-CNVs) are characterized by heterogeneous phenotypes thought to share a considerable degree of overlap. Altered neural integration has often been linked to psychopathology and is a candidate marker for potential convergent mechanisms through which ND-CNVs modify risk; however, the rarity of ND-CNVs means that few studies have assessed their neural correlates. Here, we used magnetoencephalography (MEG) to investigate resting-state oscillatory connectivity in a cohort of 42 adults with ND-CNVs, including deletions or duplications at 22q11.2, 15q11.2, 15q13.3, 16p11.2, 17q12, 1q21.1, 3q29, and 2p16.3, and 42 controls. We observed decreased connectivity between occipital, temporal, and parietal areas in participants with ND-CNVs. This pattern was common across genotypes and not exclusively characteristic of 22q11.2 deletions, which were present in a third of our cohort. Furthermore, a data-driven graph theory framework enabled us to successfully distinguish participants with ND-CNVs from unaffected controls using differences in node centrality and network segregation. Together, our results point to alterations in electrophysiological connectivity as a putative common mechanism through which genetic factors confer increased risk for neurodevelopmental and psychiatric disorders.


Assuntos
Variações do Número de Cópias de DNA , Transtornos Mentais , Adulto , Estudos de Coortes , Predisposição Genética para Doença , Genótipo , Humanos , Fenótipo
20.
JAMA Psychiatry ; 77(4): 420-430, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31665216

RESUMO

Importance: Recurrent microdeletions and duplications in the genomic region 15q11.2 between breakpoints 1 (BP1) and 2 (BP2) are associated with neurodevelopmental disorders. These structural variants are present in 0.5% to 1.0% of the population, making 15q11.2 BP1-BP2 the site of the most prevalent known pathogenic copy number variation (CNV). It is unknown to what extent this CNV influences brain structure and affects cognitive abilities. Objective: To determine the association of the 15q11.2 BP1-BP2 deletion and duplication CNVs with cortical and subcortical brain morphology and cognitive task performance. Design, Setting, and Participants: In this genetic association study, T1-weighted brain magnetic resonance imaging were combined with genetic data from the ENIGMA-CNV consortium and the UK Biobank, with a replication cohort from Iceland. In total, 203 deletion carriers, 45 247 noncarriers, and 306 duplication carriers were included. Data were collected from August 2015 to April 2019, and data were analyzed from September 2018 to September 2019. Main Outcomes and Measures: The associations of the CNV with global and regional measures of surface area and cortical thickness as well as subcortical volumes were investigated, correcting for age, age2, sex, scanner, and intracranial volume. Additionally, measures of cognitive ability were analyzed in the full UK Biobank cohort. Results: Of 45 756 included individuals, the mean (SD) age was 55.8 (18.3) years, and 23 754 (51.9%) were female. Compared with noncarriers, deletion carriers had a lower surface area (Cohen d = -0.41; SE, 0.08; P = 4.9 × 10-8), thicker cortex (Cohen d = 0.36; SE, 0.07; P = 1.3 × 10-7), and a smaller nucleus accumbens (Cohen d = -0.27; SE, 0.07; P = 7.3 × 10-5). There was also a significant negative dose response on cortical thickness (ß = -0.24; SE, 0.05; P = 6.8 × 10-7). Regional cortical analyses showed a localization of the effects to the frontal, cingulate, and parietal lobes. Further, cognitive ability was lower for deletion carriers compared with noncarriers on 5 of 7 tasks. Conclusions and Relevance: These findings, from the largest CNV neuroimaging study to date, provide evidence that 15q11.2 BP1-BP2 structural variation is associated with brain morphology and cognition, with deletion carriers being particularly affected. The pattern of results fits with known molecular functions of genes in the 15q11.2 BP1-BP2 region and suggests involvement of these genes in neuronal plasticity. These neurobiological effects likely contribute to the association of this CNV with neurodevelopmental disorders.


Assuntos
Córtex Cerebral/anatomia & histologia , Cromossomos Humanos Par 15/genética , Cognição , Variações do Número de Cópias de DNA/genética , Espessura Cortical do Cérebro , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Pontos de Quebra do Cromossomo , Variações do Número de Cópias de DNA/fisiologia , Feminino , Estudos de Associação Genética , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Tamanho do Órgão/genética
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