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1.
PLoS One ; 17(10): e0275671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36256656

RESUMO

Human tissue surfaces are coated with mucins, a family of macromolecular sugar-laden proteins serving diverse functions from lubrication to the formation of selective biochemical barriers against harmful microorganisms and molecules. Membrane mucins are a distinct group of mucins that are attached to epithelial cell surfaces where they create a dense glycocalyx facing the extracellular environment. All mucin proteins carry long stretches of tandemly repeated sequences that undergo extensive O-linked glycosylation to form linear mucin domains. However, the repetitive nature of mucin domains makes them prone to recombination and renders their genetic sequences particularly difficult to read with standard sequencing technologies. As a result, human mucin genes suffer from significant sequence gaps that have hampered the investigation of gene function in health and disease. Here we leveraged a recent human genome assembly to characterize a previously unmapped MUC3B gene located at the q22 locus on chromosome 7, within a cluster of four structurally related membrane mucin genes that we name the MUC3 cluster. We found that MUC3B shares high sequence identity with the known MUC3A gene and that the two genes are governed by evolutionarily conserved regulatory elements. Furthermore, we show that MUC3A, MUC3B, MUC12, and MUC17 in the human MUC3 cluster are expressed in intestinal epithelial cells (IECs). Our results complete existing genetic gaps in the MUC3 cluster which is a conserved genetic unit in vertebrates. We anticipate our results to be the starting point for the detection of disease-associated polymorphisms in the human MUC3 cluster. Moreover, our study provides the basis for the exploration of intestinal mucin gene function in widely used experimental models such as human intestinal organoids and genetic mouse models.


Assuntos
Cromossomos Humanos Par 7 , Mucinas , Animais , Humanos , Camundongos , Sequência de Aminoácidos , Cromossomos Humanos Par 7/metabolismo , Mucosa Intestinal/metabolismo , Mucina-2/genética , Mucinas/metabolismo , Família Multigênica , Açúcares/metabolismo
2.
Sci Rep ; 11(1): 8246, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859276

RESUMO

Recurrent deletions and duplications of chromosome 7q11.23 copy number variants (CNVs) are associated with several psychiatric disorders. Although phenotypic abnormalities have been observed in patients, causal genes responsible for CNV-associated diagnoses and traits are still poorly understood. Furthermore, the targeted human brain regions, developmental stages, protein networks, and signaling pathways, influenced by this CNV remain unclear. Previous works showed GTF2I involved in Williams-Beuren syndrome, but pathways affected by GTF2I are indistinct. We first constructed dynamic spatiotemporal networks of 7q11.23 genes by combining data from the brain developmental transcriptome with physical interactions of 7q11.23 proteins. Topological changes were observed in protein-protein interaction (PPI) networks throughout different stages of brain development. Early and late fetal periods of development in the cortex, striatum, hippocampus, and amygdale were observed as the vital periods and regions for 7q11.23 CNV proteins. CNV proteins and their partners are significantly enriched in DNA repair pathway. As a driver gene, GTF2I interacted with PRKDC and BRCA1 to involve in DNA repair pathway. The physical interaction between GTF2I with PRKDC was confirmed experimentally by the liquid chromatography-tandem mass spectrometry (LC-MS/MS). We identified that early and late fetal periods are crucial for 7q11.23 genes to affect brain development. Our results implicate that 7q11.23 CNV genes converge on the DNA repair pathway to contribute to the pathogenesis of psychiatric diseases.


Assuntos
Encéfalo/embriologia , Cromossomos Humanos Par 7/genética , Reparo do DNA , Mapas de Interação de Proteínas , Adolescente , Adulto , Encéfalo/metabolismo , Criança , Pré-Escolar , Cromossomos Humanos Par 7/metabolismo , Biologia Computacional , Variações do Número de Cópias de DNA , Reparo do DNA/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes/genética , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Transtornos Mentais/genética , Gravidez , Mapas de Interação de Proteínas/genética , Proteoma/análise , Proteoma/genética , Proteoma/metabolismo , Transdução de Sinais/genética , Transcriptoma/genética , Adulto Jovem
3.
Pigment Cell Melanoma Res ; 34(5): 987-993, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33522711

RESUMO

Patients with non-supernumerary ring chromosome 7 syndrome have an increased incidence of hemangiomas, café-au-lait spots, and melanocytic nevi. The mechanism for the increased incidence of these benign neoplasms is unknown. We present the case of a 22-year-old man with ring chromosome 7 and multiple melanocytic nevi. Two nevi, one on the right ear and the other on the right knee, were biopsied and diagnosed as desmoplastic Spitz nevi. Upon targeted next-generation DNA sequencing, both harbored BRAF fusions. Copy number alterations and fluorescence in situ hybridization (FISH) for BRAF suggested that the fusions arose on the ring chromosome 7. Hence, one reason for increased numbers of nevi in patients with non-supernumerary ring chromosome 7 syndrome may be increased likelihood of BRAF fusions, due to the instability of the ring chromosome.


Assuntos
Transtornos Cromossômicos , Neoplasias da Orelha , Nevo de Células Epitelioides e Fusiformes , Proteínas de Fusão Oncogênica , Proteínas Proto-Oncogênicas B-raf , Cromossomos em Anel , Neoplasias Cutâneas , Adulto , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Cromossomos Humanos Par 7/fisiologia , Neoplasias da Orelha/genética , Neoplasias da Orelha/metabolismo , Neoplasias da Orelha/patologia , Humanos , Masculino , Nevo de Células Epitelioides e Fusiformes/genética , Nevo de Células Epitelioides e Fusiformes/metabolismo , Nevo de Células Epitelioides e Fusiformes/patologia , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
4.
J Clin Invest ; 131(4)2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33373325

RESUMO

Autosomal dominant sterile α motif domain containing 9 (Samd9) and Samd9L (Samd9/9L) syndromes are a large subgroup of currently established inherited bone marrow failure syndromes that includes myelodysplasia, infection, growth restriction, adrenal hypoplasia, genital phenotypes, and enteropathy (MIRAGE), ataxia pancytopenia, and familial monosomy 7 syndromes. Samd9/9L genes are located in tandem on chromosome 7 and have been known to be the genes responsible for myeloid malignancies associated with monosomy 7. Additionally, as IFN-inducible genes, Samd9/9L are crucial for protection against viruses. Samd9/9L syndromes are caused by gain-of-function mutations and develop into infantile myelodysplastic syndromes associated with monosomy 7 (MDS/-7) at extraordinarily high frequencies. We generated mice expressing Samd9LD764N, which mimic MIRAGE syndrome, presenting with growth retardation, a short life, bone marrow failure, and multiorgan degeneration. In hematopoietic cells, Samd9LD764N downregulates the endocytosis of transferrin and c-Kit, resulting in a rare cause of anemia and a low bone marrow reconstitutive potential that ultimately causes MDS/-7. In contrast, in nonhematopoietic cells we tested, Samd9LD764N upregulated the endocytosis of EGFR by Ship2 phosphatase translocation to the cytomembrane and activated lysosomes, resulting in the reduced expression of surface receptors and signaling. Thus, Samd9/9L is a downstream regulator of IFN that controls receptor metabolism, with constitutive activation leading to multiorgan dysfunction.


Assuntos
Receptores ErbB/metabolismo , Mutação com Ganho de Função , Transtornos Mieloproliferativos/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Modelos Animais de Doenças , Receptores ErbB/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Transgênicos , Transtornos Mieloproliferativos/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Síndrome , Proteínas Supressoras de Tumor/genética
5.
Genes (Basel) ; 11(12)2020 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291420

RESUMO

Silver-Russell syndrome (SRS) is a rare growth-related genetic disorder that is mainly associated with prenatal and postnatal growth retardation. Molecular causes are not clear in all cases, the most common ones being loss of methylation on chromosome 11p15 (≈50%) and maternal uniparental disomy for chromosome 7 (upd(7)mat) (≈10%). However, pathogenic variants in genes such as CDKN1C, HMGA2, IGF2, or PLAG1 have also been described. Previously, two families and one sporadic case have been reported with PLAG1 alterations. Here, we present a case of a female with clinical suspicion of SRS (i.e., intrauterine and postnatal growth retardation, triangular face, psychomotor delay, speech delay, feeding difficulties). No alterations in methylation or copy number were detected at chromosomes 11p15 and 7 using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA). The custom panel study by next-generation sequencing (NGS) revealed a frameshift variant in the PLAG1 gene (NM_002655.3:c.551delA; p.(Lys184Serfs *45)). Familial studies confirmed that the variant was inherited from the mother and it was also present in other family members. New evidence of pathogenic alterations in the HMGA2-PLAG1-IGF2 pathway suggest the importance of studying and taking into account these genes as alternative molecular causes of Silver-Russell syndrome.


Assuntos
Proteínas de Ligação a DNA/genética , Família , Mutação da Fase de Leitura , Síndrome de Silver-Russell/genética , Criança , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Síndrome de Silver-Russell/metabolismo
6.
Mol Autism ; 11(1): 88, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33208191

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental condition affecting almost 1% of children, and represents a major unmet medical need with no effective drug treatment available. Duplication at 7q11.23 (7Dup), encompassing 26-28 genes, is one of the best characterized ASD-causing copy number variations and offers unique translational opportunities, because the hemideletion of the same interval causes Williams-Beuren syndrome (WBS), a condition defined by hypersociability and language strengths, thereby providing a unique reference to validate treatments for the ASD symptoms. In the above-indicated interval at 7q11.23, defined as WBS critical region, several genes, such as GTF2I, BAZ1B, CLIP2 and EIF4H, emerged as critical for their role in the pathogenesis of WBS and 7Dup both from mouse models and human studies. METHODS: We performed a high-throughput screening of 1478 compounds, including central nervous system agents, epigenetic modulators and experimental substances, on patient-derived cortical glutamatergic neurons differentiated from our cohort of induced pluripotent stem cell lines (iPSCs), monitoring the transcriptional modulation of WBS interval genes, with a special focus on GTF2I, in light of its overriding pathogenic role. The hits identified were validated by measuring gene expression by qRT-PCR and the results were confirmed by western blotting. RESULTS: We identified and selected three histone deacetylase inhibitors (HDACi) that decreased the abnormal expression level of GTF2I in 7Dup cortical glutamatergic neurons differentiated from four genetically different iPSC lines. We confirmed this effect also at the protein level. LIMITATIONS: In this study, we did not address the molecular mechanisms whereby HDAC inhibitors act on GTF2I. The lead compounds identified will now need to be advanced to further testing in additional models, including patient-derived brain organoids and mouse models recapitulating the gene imbalances of the 7q11.23 microduplication, in order to validate their efficacy in rescuing phenotypes across multiple functional layers within a translational pipeline towards clinical use. CONCLUSIONS: These results represent a unique opportunity for the development of a specific class of compounds for treating 7Dup and other forms of intellectual disability and autism.


Assuntos
Transtorno do Espectro Autista/patologia , Córtex Cerebral/patologia , Duplicação Cromossômica/genética , Cromossomos Humanos Par 7/genética , Ensaios de Triagem em Larga Escala , Inibidores de Histona Desacetilases/farmacologia , Neurônios/patologia , Fatores de Transcrição TFII/genética , Transtorno do Espectro Autista/genética , Cromossomos Humanos Par 7/metabolismo , Variações do Número de Cópias de DNA/genética , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição TFII/metabolismo , Transcrição Gênica/efeitos dos fármacos
7.
Best Pract Res Clin Haematol ; 33(3): 101197, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33038986

RESUMO

Increasing awareness about germline predisposition and the widespread application of unbiased whole exome sequencing contributed to the discovery of new clinical entities with high risk for the development of haematopoietic malignancies. The revised 2016 WHO classification introduced a novel category of "myeloid neoplasms with germline predisposition" with GATA2, CEBPA, DDX41, RUNX1, ANKRD26 and ETV6 genes expanding the spectrum of hereditary myeloid neoplasms (MN). Since then, more germline causes of MN were identified, including SAMD9, SAMD9L, and ERCC6L2. This review describes the genetic and clinical spectrum of predisposition to MN. The main focus lies in delineation of phenotypes, genetics and management of GATA2 deficiency and the novel SAMD9/SAMD9L-related disorders. Combined, GATA2 and SAMD9/SAMD9L (SAMD9/9L) syndromes are recognized as most frequent causes of primary paediatric myelodysplastic syndromes, particularly in setting of monosomy 7. To date, ~550 cases with germline GATA2 mutations, and ~130 patients with SAMD9/9L mutations had been reported in literature. GATA2 deficiency is a highly penetrant disorder with a progressive course that often rapidly necessitates bone marrow transplantation. In contrast, SAMD9/9L disorders show incomplete penetrance with various clinical outcomes ranging from spontaneous haematological remission observed in young children to malignant progression.


Assuntos
Deficiência de GATA2 , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Neoplasias Hematológicas , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Transtornos Mieloproliferativos , Proteínas Supressoras de Tumor/genética , Deleção Cromossômica , Cromossomos Humanos Par 7/metabolismo , Deficiência de GATA2/diagnóstico , Deficiência de GATA2/genética , Deficiência de GATA2/terapia , Fator de Transcrição GATA2/genética , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/terapia , Humanos , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/terapia , Síndrome
8.
Exp Hematol ; 87: 25-32, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32544417

RESUMO

Recurrent chromosomal deletions spanning several megabases are often found in hematological malignancies. The ability to engineer deletions in model systems to functionally study their effects on the phenotype would enable, first, determination of whether a given deletion is pathogenic or neutral and, second, identification of the critical genes. Incomplete synteny makes modeling of deletions of megabase scale challenging or impossible in the mouse or other model organisms. Furthermore, despite the breakthroughs in targeted nuclease technologies in recent years, engineering of megabase-scale deletions remains challenging and has not been achieved in normal diploid human cells. Large deletions of the long arm of chromosome 7 (chr7q) occur frequently in myelodysplastic syndrome (MDS) and are associated with poor prognosis. We previously found that we can model chr7q deletions in human induced pluripotent stem cells (iPSCs) using a modified Cre-loxP strategy. However, this strategy did not afford control over the length and boundaries of the engineered deletions, which were initiated through random chromosome breaks. Here we developed strategies enabling the generation of defined and precise chromosomal deletions of up to 22 Mb, using two different strategies: "classic" Cre-loxP recombination and CRISPR/Cas9-mediated DNA cleavage. As proof of principle, we illustrate that phenotypic characterization of the hematopoiesis derived from these iPSCs upon in vitro differentiation allows further definition of the critical region of chr7q whose hemizygosity impairs hematopoietic differentiation potential. The strategies we present here can be broadly applicable to engineering of diverse chromosomal deletions in human cells.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 7 , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Humanos , Integrases/genética , Integrases/metabolismo , Camundongos
9.
Cancer Commun (Lond) ; 40(4): 167-180, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32279463

RESUMO

BACKGROUND: The preoperative prediction of muscular invasion status is important for adequately treating bladder cancer (BC) but nevertheless, there are some existing dilemmas in the current preoperative diagnostic accuracy of BC with muscular invasion. Here, we investigated the potential association between the fluorescence in situ hybridization (FISH) assay and muscular invasion among patients with BC. A cytogenetic-clinical nomogram for the individualized preoperative differentiation of muscle-invasive BC (MIBC) from non-muscle-invasive BC (NMIBC) is also proposed. METHODS: All eligible BC patients were preoperatively tested using a FISH assay, which included 4 sites (chromosome-specific centromeric probe [CSP] 3, 7, and 17, and gene locus-specific probe [GLP]-p16 locus). The correlation between the FISH assay and BC muscular invasion was evaluated using the Chi-square tests. In the training set, univariate and multivariate logistic regression analyses were used to develop a cytogenetic-clinical nomogram for preoperative muscular invasion prediction. Then, we assessed the performance of the nomogram in the training set with respect to its discriminatory accuracy and calibration for predicting muscular invasion, and clinical usefulness, which were then validated in the validation set. Moreover, model comparison was set to evaluate the discrimination and clinical usefulness between the nomogram and the individual variables incorporated in the nomogram. RESULTS: Muscular invasion was more prevalent in BC patients with positive CSP3, CSP7 and CSP17 status (OR [95% CI], 2.724 [1.555 to 4.774], P < 0.001; 3.406 [1.912 to 6.068], P < 0.001 and 2.483 [1.436 to 4.292], P = 0.001, respectively). Radiology-determined tumor size, radiology-determined clinical tumor stage and CSP7 status were identified as independent risk factors of BC muscular invasion by the multivariate regression analysis in the training set. Then, a cytogenetic-clinical nomogram incorporating these three independent risk factors was constructed and was observed to have satisfactory discrimination in the training (AUC 0.784; 95% CI: 0.715 to 0.853) and validation (AUC 0.743; 95% CI: 0.635 to 0.850) set. The decision curve analysis (DCA) indicated the clinical usefulness of our nomogram. In models comparison, using the receiver operator characteristic (ROC) analyses, the nomogram showed higher discriminatory accuracy than any variables incorporated in the nomogram alone and the DCAs also identified the nomogram as possessing the highest net benefits at wide range of threshold probabilities. CONCLUSION: CSP7 status was identified as an independent factor for predicting muscular invasion in BC patients and was successfully incorporated in a clinical nomogram combining the results of the FISH assay with clinical risk factors.


Assuntos
Cromossomos Humanos Par 7/metabolismo , Hibridização in Situ Fluorescente/métodos , Neoplasias da Bexiga Urinária/genética , Idoso , Aneuploidia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/patologia
10.
Ann Hematol ; 99(3): 527-537, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31989250

RESUMO

Azacitidine (AZA) is a DNA hypomethylation agent administered in myeloid neoplasms; however, there is still a lack of established predictors of response. We studied 113 patients with myelodysplastic syndromes (n = 85) or acute myeloid leukemia (n = 28) who received AZA to assess the predictive value on response of clinical features, cytogenetics, and molecular markers. Overall, 46 patients (41%) responded to AZA. Platelet doubling after the first AZA cycle was associated with a better response (68% vs. 32% responders, P = 0.041). Co-occurrence of chromosome 7 abnormalities and 17p deletion was associated with a worse response (P = 0.039). Pre-treatment genetic mutations were detected in 98 patients (87%) and methylation of CDKN2B and DLC-1 promoters were detected in 50 (44%) and 37 patients (33%), respectively. Patients with SF3B1 mutations showed a better response to AZA (68% vs. 35% responders, P = 0.008). In contrast, subjects with mutations in transcription factors (RUNX1, SETBP1, NPM1) showed a worse response (20% vs. 47% responders, P = 0.014). DLC-1 methylation pre-treatment was associated with poor clinical features and its reduction post-treatment resulted in a better response to AZA in MDS patients (P = 0.037). In conclusion, we have identified several predictors of response to AZA that could help select the best candidates for this treatment.


Assuntos
Azacitidina/administração & dosagem , Inibidor de Quinase Dependente de Ciclina p15 , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias , Proteínas Ativadoras de GTPase , Síndromes Mielodisplásicas , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor , Idoso , Idoso de 80 Anos ou mais , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Intervalo Livre de Doença , Feminino , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/mortalidade , Nucleofosmina , Taxa de Sobrevida , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
11.
Nucleic Acids Res ; 48(1): 472-485, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31745551

RESUMO

Site-specific recombinases (SSRs) such as the Cre/loxP system are useful genome engineering tools that can be repurposed by altering their DNA-binding specificity. However, SSRs that delete a natural sequence from the human genome have not been reported thus far. Here, we describe the generation of an SSR system that precisely excises a 1.4 kb fragment from the human genome. Through a streamlined process of substrate-linked directed evolution we generated two separate recombinases that, when expressed together, act as a heterodimer to delete a human genomic sequence from chromosome 7. Our data indicates that designer-recombinases can be generated in a manageable timeframe for precision genome editing. A large-scale bioinformatics analysis suggests that around 13% of all human protein-coding genes could be targetable by dual designer-recombinase induced genomic deletion (dDRiGD). We propose that heterospecific designer-recombinases, which work independently of the host DNA repair machinery, represent an efficient and safe alternative to nuclease-based genome editing technologies.


Assuntos
Sequência de Bases , Cromossomos Humanos Par 7/química , DNA Nucleotidiltransferases/genética , Edição de Genes/métodos , Genoma Humano , Deleção de Sequência , Cromossomos Humanos Par 7/metabolismo , Clonagem Molecular , Biologia Computacional/métodos , DNA Nucleotidiltransferases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Loci Gênicos , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
12.
PLoS One ; 14(2): e0211799, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30707743

RESUMO

Genomic imprinting is important for normal brain development and aberrant imprinting has been associated with impaired cognition. We studied the imprinting status in selected imprints (H19, IGF2, SNRPN, PEG3, MEST1, NESPAS, KvDMR, IG-DMR and ZAC1) by pyrosequencing in blood samples from longitudinal cohorts born in 1936 (n = 485) and 1921 (n = 223), and anterior hippocampus, posterior hippocampus, periventricular white matter, and thalamus from brains donated to the Aberdeen Brain Bank (n = 4). MEST1 imprint methylation was related to childhood cognitive ability score (-0.416 95% CI -0.792,-0.041; p = 0.030), with the strongest effect evident in males (-0.929 95% CI -1.531,-0.326; p = 0.003). SNRPN imprint methylation was also related to childhood cognitive ability (+0.335 95%CI 0.008,0.663; p = 0.045). A significant association was also observed for SNRPN methylation and adult crystallised cognitive ability (+0.262 95%CI 0.007,0.517; p = 0.044). Further testing of significant findings in a second cohort from the same region, but born in 1921, resulted in similar effect sizes and greater significance when the cohorts were combined (MEST1; -0.371 95% CI -0.677,-0.065; p = 0.017; SNRPN; +0.361 95% CI 0.079,0.643; p = 0.012). For SNRPN and MEST1 and four other imprints the methylation levels in blood and in the five brain regions were similar. Methylation of the paternally expressed, maternally methylated genes SNRPN and MEST1 in adult blood was associated with cognitive ability in childhood. This is consistent with the known importance of the SNRPN containing 15q11-q13 and the MEST1 containing 7q31-34 regions in cognitive function. These findings, and their sex specific nature in MEST1, point to new mechanisms through which complex phenotypes such as cognitive ability may be inherited. These mechanisms are potentially relevant to both the heritable and non-heritable components of cognitive ability. The process of epigenetic imprinting-within SNRPN and MEST1 in particular-and the factors that influence it, are worthy of further study in relation to the determinants of cognitive ability.


Assuntos
Encéfalo/metabolismo , Cognição/fisiologia , Impressão Genômica/fisiologia , Proteínas/metabolismo , Proteínas Centrais de snRNP/sangue , Adulto , Idoso , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 15/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas/genética , Proteínas Centrais de snRNP/genética
13.
Exp Hematol ; 69: 27-36, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30352278

RESUMO

Acute myeloid leukemia (AML) is a complex, heterogeneous disease with variable outcomes following curative intent chemotherapy. AML with inv(3) is a genetic subgroup characterized by a very low response rate to current induction type chemotherapy and thus has among the worst long-term survivorship of the AMLs. Here, we describe OCI-AML-20, a new AML cell line with inv(3) and deletion of chromosome 7; the latter is a common co-occurrence in inv(3) AML. In OCI-AML-20, CD34 expression is maintained and required for repopulation in vitro and in vivo. CD34 expression in OCI-AML-20 shows dependence on the co-culture with stromal cells. Transcriptome analysis indicates that the OCI-AML-20 clusters with other AML patient data sets that have poor prognosis, as well as other AML cell lines, including another inv(3) line, MUTZ-3. OCI-AML-20 is a new cell line resource for studying the biology of inv(3) AML that can be used to identify potential therapies for this poor outcome disease.


Assuntos
Antígenos CD34/biossíntese , Linhagem Celular Tumoral , Deleção Cromossômica , Inversão Cromossômica , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 7/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda , Proteínas de Neoplasias/biossíntese , Adulto , Antígenos CD34/genética , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/patologia , Cromossomos Humanos Par 3/metabolismo , Cromossomos Humanos Par 7/metabolismo , Técnicas de Cocultura , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Masculino , Proteínas de Neoplasias/genética , Células Estromais/metabolismo , Células Estromais/patologia
14.
Hematol Oncol Clin North Am ; 32(4): 729-743, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30047423

RESUMO

Myelodysplastic syndromes (MDS) in children and adolescents are a rare heterogeneous group of clonal stem cell disorders. Complete or partial loss of chromosome 7 constitutes the most common cytogenetic abnormality encountered in any type of childhood MDS, is associated with more advanced disease, and usually requires a timely allogeneic stem cell transplantation. This article provides insights into the current understanding of the genotype, phenotype, and clonal evolution patterns in pediatric MDS associated with loss of chromosome 7.


Assuntos
Deleção Cromossômica , Evolução Clonal , Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas , Adolescente , Aloenxertos , Criança , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Humanos , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/terapia
15.
Haematologica ; 103(10): 1662-1668, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29903756

RESUMO

Therapy-related acute lymphoblastic leukemia remains poorly defined due to a lack of large data sets recognizing the defining characteristics of this entity. We reviewed all consecutive cases of adult acute lymphoblastic leukemia treated at our institution between 2000 and 2017 and identified therapy-related cases - defined as acute lymphoblastic leukemia preceded by prior exposure to cytotoxic chemotherapy and/or radiation. Of 1022 patients with acute lymphoblastic leukemia, 93 (9.1%) were classified as therapy-related. The median latency for therapy-related acute lymphoblastic leukemia onset was 6.8 years from original diagnosis, and this was shorter for patients carrying the MLL gene rearrangement compared to those with other cytogenetics. When compared to de novo acute lymphoblastic leukemia, therapy-related patients were older (P<0.01), more often female (P<0.01), and had more MLL gene rearrangement (P<0.0001) and chromosomes 5/7 aberrations (P=0.02). Although therapy-related acute lymphoblastic leukemia was associated with inferior 2-year overall survival compared to de novo cases (46.0% vs 68.1%, P=0.001), prior exposure to cytotoxic therapy (therapy-related) did not independently impact survival in multivariate analysis (HR=1.32; 95% CI: 0.97-1.80, P=0.08). There was no survival difference (2-year = 53.4% vs 58.9%, P=0.68) between the two groups in patients who received allogenic hematopoietic cell transplantation. In conclusion, therapy-related acute lymphoblastic leukemia represents a significant proportion of adult acute lymphoblastic leukemia diagnoses, and a subset of cases carry clinical and cytogenetic abnormalities similar to therapy-related myeloid neoplasms. Although survival of therapy-related acute lymphoblastic leukemia was inferior to de novo cases, allogeneic hematopoietic cell transplantation outcomes were comparable for the two entities.


Assuntos
Aberrações Cromossômicas , Rearranjo Gênico , Histona-Lisina N-Metiltransferase , Proteína de Leucina Linfoide-Mieloide , Segunda Neoplasia Primária , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 5/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Intervalo Livre de Doença , Feminino , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/metabolismo , Segunda Neoplasia Primária/mortalidade , Segunda Neoplasia Primária/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Fatores Sexuais , Taxa de Sobrevida
17.
Elife ; 42015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25942454

RESUMO

Cancer cells display aneuploid karyotypes and typically mis-segregate chromosomes at high rates, a phenotype referred to as chromosomal instability (CIN). To test the effects of aneuploidy on chromosome segregation and other mitotic phenotypes we used the colorectal cancer cell line DLD1 (2n = 46) and two variants with trisomy 7 or 13 (DLD1+7 and DLD1+13), as well as euploid and trisomy 13 amniocytes (AF and AF+13). We found that trisomic cells displayed higher rates of chromosome mis-segregation compared to their euploid counterparts. Furthermore, cells with trisomy 13 displayed a distinctive cytokinesis failure phenotype. We showed that up-regulation of SPG20 expression, brought about by trisomy 13 in DLD1+13 and AF+13 cells, is sufficient for the cytokinesis failure phenotype. Overall, our study shows that aneuploidy can induce chromosome mis-segregation. Moreover, we identified a trisomy 13-specific mitotic phenotype that is driven by up-regulation of a gene encoded on the aneuploid chromosome.


Assuntos
Instabilidade Cromossômica , Transtornos Cromossômicos/genética , Cromossomos Humanos Par 13/química , Cromossomos Humanos Par 7/química , Proteínas/genética , Trissomia/genética , Líquido Amniótico/citologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Transtornos Cromossômicos/metabolismo , Transtornos Cromossômicos/patologia , Segregação de Cromossomos , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 13/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Colo/metabolismo , Colo/patologia , Citocinese/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Feto , Regulação da Expressão Gênica , Humanos , Cariotipagem , Fenótipo , Gravidez , Cultura Primária de Células , Proteínas/metabolismo , Trissomia/patologia , Síndrome da Trissomia do Cromossomo 13
18.
Blood ; 125(4): 706-9, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25406353

RESUMO

The pathophysiology of severe aplastic anemia (SAA) is immune-mediated destruction of hematopoietic stem and progenitor cells (HSPCs). Most patients respond to immunosuppressive therapies, but a minority transform to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), frequently associated with monosomy 7 (-7). Thirteen SAA patients were analyzed for acquired mutations in myeloid cells at the time of evolution to -7, and all had a dominant HSPC clone bearing specific acquired mutations. However, mutations in genes associated with MDS/AML were present in only 4 cases. Patients who evolved to MDS and AML showed marked progressive telomere attrition before the emergence of -7. Single telomere length analysis confirmed accumulation of short telomere fragments of individual chromosomes. Our results indicate that accelerated telomere attrition in the setting of a decreased HSPC pool is characteristic of early myeloid oncogenesis, specifically chromosome 7 loss, in MDS/AML after SAA, and provides a possible mechanism for development of aneuploidy.


Assuntos
Anemia Aplástica/genética , Células-Tronco Hematopoéticas , Homeostase do Telômero , Anemia Aplástica/metabolismo , Anemia Aplástica/patologia , Deleção Cromossômica , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Masculino , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia
19.
Tsitologiia ; 57(11): 771-9, 2015.
Artigo em Russo | MEDLINE | ID: mdl-27012091

RESUMO

Adenomyosis is form of endometriosis, common diseases of female reproductive system, which can lead to infertility in women. in this study we are obtained and characterized cell line endometrial mesenchymal stem cells from a patient with adenomyosis, and compare obtained cells with the cell line of healthy donor. Aim of this study was to assesses the extent of differences between cells from donor with adenomyosis and cells from healthy donor. Was established that compared lines had morphology like fibroblasts, were differentiated in adipocytes, were expressed mesenchymal markers and didn't expressed haematopoietic markers. Cytogenetic analysis of differentially stained metaphase chromosomes on G-banding (passage 6-7) showed that healthy donor's cells had predominantly normal karyotype. The cellular line from a patient with diagnosis of "adenomyosis" had a lot of cells with changes in karyotype's structure. These changes were related with aneuploidy of cellular population and the presence non-random chromosomal breaks, often in chromosomes 7 and 11. Analysis of this data allows the cells from adenomyosis characterized physiological stability in culture and karyotypic instability with non-random involvement certain chromosomal set. The cellular line obtained from donor with adenomyosis showed signs destabilization of he genome, typical for cell transformation. Division of adenomyosis cells to the 26th passage is stopped and these cells entered into a phase of replicative aging. Based on this, we can conclude that founded karyotype's hanges do not lead to transformation and immortalization of cells in vitro.


Assuntos
Adenomiose/metabolismo , Aneuploidia , Endométrio/metabolismo , Células-Tronco Mesenquimais/metabolismo , Adenomiose/genética , Adenomiose/patologia , Senescência Celular , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Endométrio/patologia , Feminino , Humanos , Células-Tronco Mesenquimais/patologia
20.
Blood ; 124(24): 3577-82, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25270907

RESUMO

MYC translocations represent a genetic subtype of T-lineage acute lymphoblastic leukemia (T-ALL), which occurs at an incidence of ∼6%, assessed within a cohort of 196 T-ALL patients (64 adults and 132 children). The translocations were of 2 types; those rearranged with the T-cell receptor loci and those with other partners. MYC translocations were significantly associated with the TAL/LMO subtype of T-ALL (P = .018) and trisomies 6 (P < .001) and 7 (P < .001). Within the TAL/LMO subtype, gene expression profiling identified 148 differentially expressed genes between patients with and without MYC translocations; specifically, 77 were upregulated and 71 downregulated in those with MYC translocations. The poor prognostic marker, CD44, was among the upregulated genes. MYC translocations occurred as secondary abnormalities, present in subclones in one-half of the cases. Longitudinal studies indicated an association with induction failure and relapse.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Translocação Genética , Adolescente , Adulto , Criança , Pré-Escolar , Cromossomos Humanos Par 6/genética , Cromossomos Humanos Par 6/metabolismo , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 7/metabolismo , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Receptores de Hialuronatos/biossíntese , Receptores de Hialuronatos/genética , Masculino , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Taxa de Sobrevida , Trissomia/genética
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