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1.
Mol Cell ; 80(1): 140-155.e6, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007254

RESUMO

The tissue-specific deployment of highly extended neural 3' UTR isoforms, generated by alternative polyadenylation (APA), is a broad and conserved feature of metazoan genomes. However, the factors and mechanisms that control neural APA isoforms are not well understood. Here, we show that three ELAV/Hu RNA binding proteins (Elav, Rbp9, and Fne) have similar capacities to induce a lengthened 3' UTR landscape in an ectopic setting. These factors promote accumulation of chromatin-associated, 3' UTR-extended, nascent transcripts, through inhibition of proximal polyadenylation site (PAS) usage. Notably, Elav represses an unannotated splice isoform of fne, switching the normally cytoplasmic Fne toward the nucleus in elav mutants. We use genomic profiling to reveal strong and broad loss of neural APA in elav/fne double mutant CNS, the first genetic background to largely abrogate this distinct APA signature. Overall, we demonstrate how regulatory interplay and functionally overlapping activities of neural ELAV/Hu RBPs drives the neural APA landscape.


Assuntos
Regiões 3' não Traduzidas/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Proteínas ELAV/metabolismo , Neurônios/metabolismo , Processamento Alternativo/genética , Motivos de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas ELAV/química , Larva/metabolismo , Mutação/genética , Poli A/metabolismo , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Nat Commun ; 11(1): 4974, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009381

RESUMO

Generation of bispecific antibodies (bsAbs) requires a combination of compatible binders in formats that support desired functionalities. Here, we report that bsAb-matrices can be generated by Format Chain Exchange (FORCE), enabling screening of combinatorial binder/format spaces. Input molecules for generation of bi/multi-valent bsAbs are monospecific entities similar to knob-into-hole half-antibodies, yet with complementary CH3-interface-modulated and affinity-tagged dummy-chains. These contain mutations that lead to limited interface repulsions without compromising expression or biophysical properties of educts. Mild reduction of combinations of educts triggers spontaneous chain-exchange reactions driven by partially flawed CH3-educt interfaces resolving to perfect complementarity. This generates large bsAb matrices harboring different binders in multiple formats. Benign biophysical properties and good expression yields of educts, combined with simplicity of purification enables process automation. Examples that demonstrate the relevance of screening binder/format combinations are provided as a matrix of bsAbs that simultaneously bind Her1/Her2 and DR5 without encountering binder or format-inflicted interferences.


Assuntos
Anticorpos Biespecíficos/biossíntese , Ensaios de Triagem em Larga Escala , Anticorpos Biespecíficos/isolamento & purificação , Automação , Células HEK293 , Humanos , Mutação/genética , Multimerização Proteica
3.
Nat Commun ; 11(1): 4627, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009389

RESUMO

Animals have evolved responses to low oxygen conditions to ensure their survival. Here, we have identified the C. elegans zinc finger transcription factor PQM-1 as a regulator of the hypoxic stress response. PQM-1 is required for the longevity of insulin signaling mutants, but surprisingly, loss of PQM-1 increases survival under hypoxic conditions. PQM-1 functions as a metabolic regulator by controlling oxygen consumption rates, suppressing hypoxic glycogen levels, and inhibiting the expression of the sorbitol dehydrogenase-1 SODH-1, a crucial sugar metabolism enzyme. PQM-1 promotes hypoxic fat metabolism by maintaining the expression of the stearoyl-CoA desaturase FAT-7, an oxygen consuming, rate-limiting enzyme in fatty acid biosynthesis. PQM-1 activity positively regulates fat transport to developing oocytes through vitellogenins under hypoxic conditions, thereby increasing survival rates of arrested progeny during hypoxia. Thus, while pqm-1 mutants increase survival of mothers, ultimately this loss is detrimental to progeny survival. Our data support a model in which PQM-1 controls a trade-off between lipid metabolic activity in the mother and her progeny to promote the survival of the species under hypoxic conditions.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Hipóxia/metabolismo , Metabolismo dos Lipídeos , Transativadores/metabolismo , Animais , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica , Glicogênio/metabolismo , Insulina/metabolismo , Larva/metabolismo , Mutação/genética , Consumo de Oxigênio , Transdução de Sinais , Estresse Fisiológico , Análise de Sobrevida , Transativadores/genética , Transcrição Genética , Vitelogeninas/metabolismo
4.
Nat Commun ; 11(1): 4941, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009412

RESUMO

Methods to directly inhibit gene expression using small molecules hold promise for the development of new therapeutics targeting proteins that have evaded previous attempts at drug discovery. Among these, small molecules including the drug-like compound PF-06446846 (PF846) selectively inhibit the synthesis of specific proteins, by stalling translation elongation. These molecules also inhibit translation termination by an unknown mechanism. Using cryo-electron microscopy (cryo-EM) and biochemical approaches, we show that PF846 inhibits translation termination by arresting the nascent chain (NC) in the ribosome exit tunnel. The arrested NC adopts a compact α-helical conformation that induces 28 S rRNA nucleotide rearrangements that suppress the peptidyl transferase center (PTC) catalytic activity stimulated by eukaryotic release factor 1 (eRF1). These data support a mechanism of action for a small molecule targeting translation that suppresses peptidyl-tRNA hydrolysis promoted by eRF1, revealing principles of eukaryotic translation termination and laying the foundation for new therapeutic strategies.


Assuntos
Terminação Traducional da Cadeia Peptídica , Preparações Farmacêuticas/metabolismo , Linhagem Celular , Humanos , Modelos Moleculares , Mutação/genética , Conformação Proteica , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , Ribossomos/ultraestrutura
5.
Zhonghua Zhong Liu Za Zhi ; 42(8): 648-652, 2020 Aug 23.
Artigo em Chinês | MEDLINE | ID: mdl-32867456

RESUMO

Objective: To investigate the relationship between KDM6A mutation or expression and clinicopathological characteristics of gastric cancer. Methods: Fifty-seven cases of gastric cancer tissues were analyzed by second-generation sequencing, and bioinformation database such as Cbioportal, Kaplan Meier-Plotter, and the Human Protein Atlas were used to analyze the relationship between KDM6A mutation and clinicopathological characteristics of gastric cancer. Results: Among 57 gastric cancer samples, 14 were KDM6A mutation, and the mutation proportion was 24.6%. Compared with the non-mutation group, the Borrmann classification, T stage, TNM stage and tumor diameter of KDM6A mutant group were significantly different (all P<0.05). The median survival time of the KDM6A mutant patients was 53.5 months, significantly shorter than 72.0 months of the KDM6A non-mutation patients (P=0.007). The analysis result of Kaplan Meier-Plotter database showed that, among all of the 875 patients, 655 patients had low KDM6A expression and 220 patients had high expression. The median survival time of patients with low expression was 23.5 months, significantly shorter than 30.8 months of patients with high expression (P=0.002). In male, gastric cancer patients with stage Ⅲ, intestinal type, diffuse type, simple surgical treatment and fluorouracil chemotherapy, the expression of KDM6A is related to the patient's overall survival time (all P<0.05). The analysis result of Cbioportal database showed that, among all of the 1 172 gastric cancer patients, 70 patients with KDM6A mutation, 1100 patients with non-mutation. The median overall survival time of mutant patients was 28.9 months, significantly shorter than 35.9 months of non-mutation patients (P<0.001). The analysis result of Human Protein Atlas database showed that, among all of the 355 gastric cancer patients, 97 patients had high KDM6A expression and 258 patients had low KDM6A expression. The median survival time of patients with low expression was 13.7 months, significantly shorter than 19.8 months of patients with high expression (P=0.022). Conclusions: The survival time of gastric cancer patients with KDM6A mutation or low expression is shorter. The mutation and expression of KDM6A are related to clinical pathological factors, which may become a potential target for the diagnosis and treatment of gastric cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Histona Desmetilases/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Histona Desmetilases/genética , Humanos , Metástase Linfática , Masculino , Mutação/genética , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida
6.
PLoS Comput Biol ; 16(9): e1008269, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941419

RESUMO

We propose an efficient framework for genetic subtyping of SARS-CoV-2, the novel coronavirus that causes the COVID-19 pandemic. Efficient viral subtyping enables visualization and modeling of the geographic distribution and temporal dynamics of disease spread. Subtyping thereby advances the development of effective containment strategies and, potentially, therapeutic and vaccine strategies. However, identifying viral subtypes in real-time is challenging: SARS-CoV-2 is a novel virus, and the pandemic is rapidly expanding. Viral subtypes may be difficult to detect due to rapid evolution; founder effects are more significant than selection pressure; and the clustering threshold for subtyping is not standardized. We propose to identify mutational signatures of available SARS-CoV-2 sequences using a population-based approach: an entropy measure followed by frequency analysis. These signatures, Informative Subtype Markers (ISMs), define a compact set of nucleotide sites that characterize the most variable (and thus most informative) positions in the viral genomes sequenced from different individuals. Through ISM compression, we find that certain distant nucleotide variants covary, including non-coding and ORF1ab sites covarying with the D614G spike protein mutation which has become increasingly prevalent as the pandemic has spread. ISMs are also useful for downstream analyses, such as spatiotemporal visualization of viral dynamics. By analyzing sequence data available in the GISAID database, we validate the utility of ISM-based subtyping by comparing spatiotemporal analyses using ISMs to epidemiological studies of viral transmission in Asia, Europe, and the United States. In addition, we show the relationship of ISMs to phylogenetic reconstructions of SARS-CoV-2 evolution, and therefore, ISMs can play an important complementary role to phylogenetic tree-based analysis, such as is done in the Nextstrain project. The developed pipeline dynamically generates ISMs for newly added SARS-CoV-2 sequences and updates the visualization of pandemic spatiotemporal dynamics, and is available on Github at https://github.com/EESI/ISM (Jupyter notebook), https://github.com/EESI/ncov_ism (command line tool) and via an interactive website at https://covid19-ism.coe.drexel.edu/.


Assuntos
Betacoronavirus/classificação , Betacoronavirus/genética , Infecções por Coronavirus , Genômica/métodos , Pandemias , Pneumonia Viral , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Evolução Molecular , Marcadores Genéticos/genética , Genoma Viral/genética , Humanos , Mutação/genética , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , RNA Viral/genética , Alinhamento de Sequência , Análise de Sequência de RNA , Análise Espaço-Temporal
7.
Anticancer Res ; 40(10): 5577-5582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988881

RESUMO

BACKGROUND/AIM: Clusters of circulating tumor cells (CTCs) increase metastatic potential compared to single CTC. However, conventional technologies have been unable to generate an accurate analysis of single and cluster CTCs in the peripheral blood. We propose an effective strategy to detect and isolate both single and cluster CTCs using two size-selective microfilters. MATERIALS AND METHODS: Five ml of whole blood were collected from 10 patients with epidermal growth factor receptor mutation-positive non-small cell lung cancer. Single and cluster CTCs were identified using precision microfiltration membranes with two distinct pore sizes together with anti-EpCAM antibody labeling. RESULTS: Single and cluster CTCs were detected by simultaneously using two size-selective microfilters. The EGFR-L858R mutation was detected in the DNA from cells captured using both microfilters. CONCLUSION: Our method can be used to detect and isolate single and cluster CTCs in the whole blood and may facilitate the development of a liquid biopsy strategy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/sangue , DNA Tumoral Circulante/sangue , Molécula de Adesão da Célula Epitelial/sangue , Células Neoplásicas Circulantes/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Separação Celular , Feminino , Humanos , Biópsia Líquida , Masculino , Pessoa de Meia-Idade , Mutação/genética , Células Neoplásicas Circulantes/patologia
8.
Anticancer Res ; 40(10): 5659-5666, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988890

RESUMO

BACKGROUND/AIM: Long interspersed nuclear element-1 (LINE-1) methylation status is a marker for global DNA methylation. However, the relationship between LINE-1 methylation and the biology of lung adenocarcinoma remains unclear. Here, we aimed to examine the role of LINE-1 in lung cancer. MATERIALS AND METHODS: LINE-1 methylation levels were quantified by bisulfite pyrosequencing of resected tumor specimens from 162 patients with lung adenocarcinoma. The relationships of LINE-1 methylation with clinicopathological factors, gene mutations, and Ki-67 immunoreactivity were investigated. RESULTS: LINE-1 hypomethylation was associated with tumor invasion and advanced stage. TP53 mutations were more frequently detected in the LINE-1 hypomethylation group than in the hypermethylation group. LINE-1 hypomethylation was associated with poor recurrence-free survival, high maximum standardized uptake value in positron-emission tomography, and high Ki-67 expression in tumors. CONCLUSION: LINE-1 hypomethylation was associated with high-grade malignancy and poor prognosis in lung adenocarcinoma, but was not related to driver mutations.


Assuntos
Adenocarcinoma de Pulmão/genética , Biomarcadores Tumorais/genética , Metilação de DNA/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Adenocarcinoma de Pulmão/patologia , Adulto , Idoso , Núcleo Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Antígeno Ki-67/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Prognóstico , Proteína Supressora de Tumor p53/genética
9.
Anticancer Res ; 40(10): 5883-5893, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988919

RESUMO

BACKGROUND/AIM: Somatic mutations were investigated in 21 patients with postmenopausal estrogen receptor (ER)-positive and human epidermal growth factor receptor-2 (HER-2)-positive (ER+HER2+) breast cancer (BC) treated with neoadjuvant letrozole and lapatinib, to identify their distinct molecular landscape. PATIENTS AND METHODS: We used tissue samples of 21 patients from phase II Neo ALL-IN cohort, and somatic alterations were examined using targeted exome sequencing performed in Foundation Medicine, Inc. (FMI). RESULTS: TP53 (61.9%) and PIK3CA (57.1%) were the two most frequently mutated genes that were inter-correlated (p=0.026). They were associated with unfavorable clinical outcomes, particularly when accompanying PIK3CA mutations at exon 9 in helical domains. Meanwhile, MLL2 alteration was negatively associated with mutations of TP53 or PIK3CA, and it tended to be present in patients with low KI-67 levels and no initial nodal involvement. Moreover, patients with MLL2 mutations numerically showed more favorable overall response rates (ORR) (80% vs. 56.2%) and better 5-year event-free survival (EFS) rates (100% vs. 87.5%) compared to the wild-type. CONCLUSION: Mutations in TP53 and PIK3CA hotspot at exon 9 may be potential negative predictors of ER+HER2+ BC treated with neoadjuvant letrozole and lapatinib, while MLL2 inactivating mutation might confer therapeutic benefit in these patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Classe I de Fosfatidilinositol 3-Quinases/genética , Proteínas de Ligação a DNA/genética , Proteínas de Neoplasias/genética , Proteína Supressora de Tumor p53/genética , Idoso , Biomarcadores Tumorais/genética , Mama/efeitos dos fármacos , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lapatinib/administração & dosagem , Letrozol/administração & dosagem , Pessoa de Meia-Idade , Mutação/genética , Intervalo Livre de Progressão , Receptor ErbB-2/genética
10.
Nat Commun ; 11(1): 4607, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929081

RESUMO

Drug tolerance is the basis for acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) including osimertinib, through mechanisms that still remain unclear. Here, we show that while AXL-low expressing EGFR mutated lung cancer (EGFRmut-LC) cells are more sensitive to osimertinib than AXL-high expressing EGFRmut-LC cells, a small population emerge osimertinib tolerance. The tolerance is mediated by the increased expression and phosphorylation of insulin-like growth factor-1 receptor (IGF-1R), caused by the induction of its transcription factor FOXA1. IGF-1R maintains association with EGFR and adaptor proteins, including Gab1 and IRS1, in the presence of osimertinib and restores the survival signal. In AXL-low-expressing EGFRmut-LC cell-derived xenograft and patient-derived xenograft models, transient IGF-1R inhibition combined with continuous osimertinib treatment could eradicate tumors and prevent regrowth even after the cessation of osimertinib. These results indicate that optimal inhibition of tolerant signals combined with osimertinib may dramatically improve the outcome of EGFRmut-LC.


Assuntos
Acrilamidas/uso terapêutico , Compostos de Anilina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor IGF Tipo 1/antagonistas & inibidores , Acrilamidas/farmacologia , Idoso de 80 Anos ou mais , Compostos de Anilina/farmacologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Imidazóis/farmacologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Regulação para Cima/efeitos dos fármacos
11.
PLoS Comput Biol ; 16(9): e1008185, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925942

RESUMO

Cells adjust their metabolism in response to mutations, but how this reprogramming depends on the genetic context is not well known. Specifically, the absence of individual enzymes can affect reprogramming, and thus the impact of mutations in cell growth. Here, we examine this issue with an in silico model of Saccharomyces cerevisiae's metabolism. By quantifying the variability in the growth rate of 10000 different mutant metabolisms that accumulated changes in their reaction fluxes, in the presence, or absence, of a specific enzyme, we distinguish a subset of modifier genes serving as buffers or potentiators of variability. We notice that the most potent modifiers refer to the glycolysis pathway and that, more broadly, they show strong pleiotropy and epistasis. Moreover, the evidence that this subset depends on the specific growing condition strengthens its systemic underpinning, a feature only observed before in a toy model of a gene-regulatory network. Some of these enzymes also modulate the effect that biochemical noise and environmental fluctuations produce in growth. Thus, the reorganization of metabolism induced by mutations has not only direct physiological implications but also transforms the influence that other mutations have on growth. This is a general result with implications in the development of cancer therapies based on metabolic inhibitors.


Assuntos
Redes Reguladoras de Genes/genética , Redes e Vias Metabólicas , Mutação , Redes e Vias Metabólicas/genética , Redes e Vias Metabólicas/fisiologia , Mutação/genética , Mutação/fisiologia , Fenótipo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Biologia de Sistemas
12.
PLoS One ; 15(8): e0237883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866169

RESUMO

Although whole-genome sequencing has provided novel insights into Neisseria meningitidis, many open reading frames have only been annotated as hypothetical proteins with unknown biological functions. Our previous genetic analyses revealed that the hypothetical protein, NMB1345, plays a crucial role in meningococcal infection in human brain microvascular endothelial cells; however, NMB1345 has no homology to any identified protein in databases and its physiological function could not be elucidated using pre-existing methods. Among the many biological technologies to examine transient protein-protein interaction in vivo, one of the developed methods is genetic code expansion with non-canonical amino acids (ncAAs) utilizing a pyrrolysyl-tRNA synthetase/tRNAPyl pair from Methanosarcina species: However, this method has never been applied to assign function-unknown proteins in pathogenic bacteria. In the present study, we developed a new method to genetically incorporate ncAAs-encoded photocrosslinking probes into N. meningitidis by utilizing a pyrrolysyl-tRNA synthetase/tRNAPyl pair and elucidated the biological function(s) of the NMB1345 protein. The results revealed that the NMB1345 protein directly interacts with PilE, a major component of meningococcal pili, and further physicochemical and genetic analyses showed that the interaction between the NMB1345 protein and PilE was important for both functional pilus formation and meningococcal infectious ability in N. meningitidis. The present study using this new methodology for N. meningitidis provides novel insights into meningococcal pathogenesis by assigning the function of a hypothetical protein.


Assuntos
Aminoácidos/genética , Reagentes para Ligações Cruzadas/metabolismo , Luz , Neisseria meningitidis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Encéfalo/irrigação sanguínea , Endocitose , Células Endoteliais/microbiologia , Fímbrias Bacterianas/metabolismo , Humanos , Microvasos/patologia , Mutação/genética , Plasmídeos/genética
13.
J Transl Med ; 18(1): 338, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878627

RESUMO

BACKGROUND: Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) caused the first coronavirus disease 2019 (COVID-19) outbreak in China and has become a public health emergency of international concern. SARS-CoV-2 outbreak has been declared a pandemic by WHO on March 11th, 2020 and the same month several Countries put in place different lockdown restrictions and testing strategies in order to contain the spread of the virus. METHODS: The calculation of the Case Fatality Rate of SARS-CoV-2 in the Countries selected was made by using the data available at https://github.com/owid/covi-19-data/tree/master/public/data . Case fatality rate was calculated as the ratio between the death cases due to COVID-19, over the total number of SARS-CoV-2 reported cases 14 days before. Standard Case Fatality Rate values were normalized by the Country-specific ρ factor, i.e. the number of PCR tests/1 million inhabitants over the number of reported cases/1 million inhabitants. Case-fatality rates between Countries were compared using proportion test. Post-hoc analysis in the case of more than two groups was performed using pairwise comparison of proportions and p value was adjusted using Holm method. We also analyzed 487 genomic sequences from the GISAID database derived from patients infected by SARS-CoV-2 from January 2020 to April 2020 in Italy, Spain, Germany, France, Sweden, UK and USA. SARS-CoV-2 reference genome was obtained from the GenBank database (NC_045512.2). Genomes alignment was performed using Muscle and Jalview software. We, then, calculated the Case Fatality Rate of SARS-CoV-2 in the Countries selected. RESULTS: In this study we analyse how different lockdown strategies and PCR testing capability adopted by Italy, France, Germany, Spain, Sweden, UK and USA have influenced the Case Fatality Rate and the viral mutations spread. We calculated case fatality rates by dividing the death number of a specific day by the number of patients with confirmed COVID-19 infection observed 14 days before and normalized by a ρ factor which takes into account the diagnostic PCR testing capability of each Country and the number of positive cases detected. We notice the stabilization of a clear pattern of mutations at sites nt241, nt3037, nt14408 and nt23403. A novel nonsynonymous SARS-CoV-2 mutation in the spike protein (nt24368) has been found in genomes sequenced in Sweden, which enacted a soft lockdown strategy. CONCLUSIONS: Strict lockdown strategies together with a wide diagnostic PCR testing of the population were correlated with a relevant decline of the case fatality rate in different Countries. The emergence of specific patterns of mutations concomitant with the decline in case fatality rate needs further confirmation and their biological significance remains unclear.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Mutação/genética , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Europa (Continente)/epidemiologia , Genoma Viral , Geografia , Humanos , América do Norte/epidemiologia , Pandemias , Análise de Sequência de DNA
14.
Yonsei Med J ; 61(8): 698-704, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32734733

RESUMO

PURPOSE: With changing fungal epidemiology and azole resistance in Aspergillus species, identifying fungal species and susceptibility patterns is crucial to the management of aspergillosis and mucormycosis. The objectives of this study were to evaluate performance of panfungal polymerase chain reaction (PCR) assays on formalin-fixed paraffin embedded (FFPE) samples in the identification of fungal species and in the detection of azole-resistance mutations in the Aspergillus fumigatus cyp51A gene at a South Korean hospital. MATERIALS AND METHODS: A total of 75 FFPE specimens with a histopathological diagnosis of aspergillosis or mucormycosis were identified during the 10-year study period (2006-2015). After deparaffinization and DNA extraction, panfungal PCR assays were conducted on FFPE samples for fungal species identification. The identified fungal species were compared with histopathological diagnosis. On samples identified as A. fumigatus, sequencing to identify frequent mutations in the cyp51A gene [tandem repeat 46 (TR46), L98H, and M220 alterations] that confer azole resistance was performed. RESULTS: Specific fungal DNA was identified in 31 (41.3%) FFPE samples, and of these, 16 samples of specific fungal DNA were in accord with a histopathological diagnosis of aspergillosis or mucormycosis; 15 samples had discordant histopathology and PCR results. No azole-mediating cyp51A gene mutation was noted among nine cases of aspergillosis. Moreover, no cyp51A mutations were identified among three cases with history of prior azole use. CONCLUSION: Panfungal PCR assay with FFPE samples may provide additional information of use to fungal species identification. No azole-resistance mediating mutations in the A. fumigatus cyp51A gene were identified among FFPE samples during study period.


Assuntos
Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/genética , Azóis/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Hospitais , Mutação/genética , Idoso , Idoso de 80 Anos ou mais , Aspergillus fumigatus/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , República da Coreia
15.
Medicine (Baltimore) ; 99(32): e20761, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769862

RESUMO

The regimens containing levofloxacin (LVX) have been recommended as an alternate to standard triple therapy to treat Helicobacter pylori infections and H pylori mixed infection always lead to H pylori chronic infection. Although the molecular mechanism of LVX resistance with gyrA gene mutation has been clearly understood in H pylori, other genes involved in antibiotic resistance remain unclear. Efflux pump plays an important role in clinically relevant multidrug resistance. Furthermore, the relationship between the strains with different LVX level-resistances from individuals is also unknown.Helicobacter pylori monoclonal strains were isolated from patients with eradication failure. E test was used to detect the minimal inhibitory concentration of LVX. One lower-level LVX-resistant clone and 2 higher-level LVX-resistant clones from the same patient were selected to sequence the complete genomes. Single-nucleotide variants (SNVs) and mutations were extracted and analyzed from gryA and resistance-nodulation-division family efflux genes.Two clones with higher-level resistance had the mutation pattern of Asn87Lys and one lower-level LVX-resistant clone had an Asp91Asn mutation. Compared to clones with higher-level resistance, the higher genetic variations were found in genes belonging to the resistance-nodulation-division family in H pylori strains with lower-level resistance to LVX. There were significantly more SNVs of Hp0970 (hefE) and Hp1329 (hefI) in the lower-level LVX-resistant clone than those in the higher-level LVX-resistant clones (P = .044).The mutation pattern of the Asn87Lys of the gyrA gene confers a higher resistance to LVX than that of the Asp91Asn in H pylori. Increase in the number of SNVs of the Hp0970 (hefE) and Hp1329 (hefI) genes change the resistance to LVX. Twelve mutations verified by Sanger sequencing in Hp0970 (hefE) and Hp1329 (hefI) may decrease resistant levels to LVX.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Levofloxacino/farmacologia , Mutação/genética , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
16.
Internist (Berl) ; 61(9): 969-979, 2020 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-32785740

RESUMO

Erdheim-Chester disease (ECD) is nowadays classified as belonging to those neoplasms with origins in the myeloid dendritic cell lines. The clonal alterations maintain a chronic inflammatory condition, which dominates the pathogenesis and clinical expression. Characteristic for ECD are many skeletal manifestations; however, the multisystem disease affects many other organs (including the respiratory tract, heart, retroperitoneum, eyes, central nervous system and endocrine system). The diagnosis is usually first made only after a disease duration of many years. This is due to the rarity of the disease and the very diffuse symptoms in addition to the heterogeneous organ manifestations. There are no uniform diagnostic criteria. The constellation of unclear polyserositis and ostealgia, possibly in association with neurological and endocrine deficiencies, should steer the suspicion towards an ECD. The diagnosis can be confirmed by an organ biopsy and the immunohistochemical examination enables the relatively certain differentiation from other forms of histiocytosis. The detection of activating oncological mutations in signal transduction pathways has opened up the possibility of targeted treatment with kinase inhibitors, such as vemurafenib for BRAF V600E mutations. Up to the discovery of activating mutations, interferon-alpha was used as the first line treatment; however, in view of the superiority of kinase inhibitors, the first line treatment with interferon-alpha currently appears to be questionable. The prognosis for untreated ECD is exceptionally poor and interferon-alpha leads to a clear improvement. Further progress is hoped for with the use of targeted treatments.


Assuntos
Doença de Erdheim-Chester/tratamento farmacológico , Interferon-alfa/uso terapêutico , Rim/fisiopatologia , Mutação/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/genética , Vemurafenib/uso terapêutico , Doença de Erdheim-Chester/diagnóstico , Doença de Erdheim-Chester/genética , Humanos , Prognóstico
17.
Lancet Neurol ; 19(9): 738-747, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32822634

RESUMO

BACKGROUND: Spinocerebellar ataxias (SCAs) are autosomal dominant neurodegenerative diseases. Our aim was to study the conversion to manifest ataxia among apparently healthy carriers of mutations associated with the most common SCAs (SCA1, SCA2, SCA3, and SCA6), and the sensitivity of clinical and functional measures to detect change in these individuals. METHODS: In this prospective, longitudinal, observational cohort study, based at 14 referral centres in seven European countries, we enrolled children or siblings of patients with SCA1, SCA2, SCA3, or SCA6. Eligible individuals were those without ataxia, defined by a score on the Scale for the Assessment and Rating of Ataxia (SARA) of less than 3; participants had to be aged 18-50 years for children or siblings of patients with SCA1, SCA2, or SCA3, and 35-70 years for children or siblings of patients with SCA6. Study visits took place at recruitment and after 2, 4, and 6 years (plus or minus 3 months). We did genetic testing to identify mutation carriers, with results concealed to the participant and clinical investigator. We assessed patients with clinical scales, questionnaires of patient-reported outcome measures, a rating of the examiner's confidence of presence of ataxia, and performance-based coordination tests. Conversion to ataxia was defined by an SARA score of 3 or higher. We analysed the association of factors at baseline with conversion to ataxia and the evolution of outcome parameters on temporal scales (time from inclusion and time to predicted age at ataxia onset) in the context of mutation status and conversion status. This study is registered with ClinicalTrials.gov, NCT01037777. FINDINGS: Between Sept 13, 2008, and Oct 28, 2015, 302 participants were enrolled. We analysed data for 252 participants with at least one follow-up visit. 83 (33%) participants were from families affected by SCA1, 99 (39%) by SCA2, 46 (18%) by SCA3, and 24 (10%) by SCA6. In participants who carried SCA mutations, 26 (52%) of 50 SCA1 carriers, 22 (59%) of 37 SCA2 carriers, 11 (42%) of 26 SCA3 carriers, and two (13%) of 15 SCA6 carriers converted to ataxia. One (3%) of 33 SCA1 non-carriers and one (2%) of 62 SCA2 non-carriers converted to ataxia. Owing to the small number of people who met our criteria for ataxia, subsequent analyses could not be done in carriers of the SCA6 mutation. Baseline factors associated with conversion were age (hazard ratio 1·13 [95% CI 1·03-1·24]; p=0·011), CAG repeat length (1·25 [1·11-1·41]; p=0·0002), and ataxia confidence rating (1·72 [1·23-2·41]; p=0·0015) for SCA1; age (1·08 [1·02-1·14]; p=0·0077) and CAG repeat length (1·65 [1·27-2·13]; p=0·0001) for SCA2; and age (1·27 [1·09-1·50]; p=0·0031), confidence rating (2·60 [1·23-5·47]; p=0·012), and double vision (14·83 [2·15-102·44]; p=0·0063) for SCA3. From the time of inclusion, the SARA scores of SCA1, SCA2, and SCA3 mutation carriers increased, whereas they remained stable in non-carriers. On a timescale defined by the predicted time of ataxia onset, SARA progression in SCA1, SCA2, and SCA3 mutation carriers was non-linear, with marginal progression before ataxia and increasing progression after ataxia onset. INTERPRETATION: Our study provides quantitative data on the conversion of non-ataxic SCA1, SCA2, and SCA3 mutation carriers to manifest ataxia. Our data could prove useful for the design of preventive trials aimed at delaying the onset of ataxia by aiding sample size calculations and stratification of study participants. FUNDING: European Research Area Network for Research Programmes on Rare Diseases, Polish Ministry of Science and Higher Education, Italian Ministry of Health, European Community's Seventh Framework Programme.


Assuntos
Progressão da Doença , Mutação/genética , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética , Adulto , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
18.
BMC Bioinformatics ; 21(1): 338, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736515

RESUMO

BACKGROUND: Analysis of somatic mutations from tumor whole exomes has fueled discovery of novel cancer driver genes. However, ~ 98% of the genome is non-coding and includes regulatory elements whose normal cellular functions can be disrupted by mutation. Whole genome sequencing (WGS), on the other hand, allows for identification of non-coding somatic variation and expanded estimation of background mutation rates, yet fewer computational tools exist for specific interrogation of this space. RESULTS: We present MutEnricher, a flexible toolset for investigating somatic mutation enrichment in both coding and non-coding genomic regions from WGS data. MutEnricher contains two distinct modules for these purposes that provide customizable options for calculating sample- and feature-specific background mutation rates. Additionally, both MutEnricher modules calculate feature-level and local, or "hotspot," somatic mutation enrichment statistics. CONCLUSIONS: MutEnricher is a flexible software package for investigating somatic mutation enrichment that is implemented in Python, is freely available, can be efficiently parallelized, and is highly configurable to researcher's specific needs. MutEnricher is available online at https://github.com/asoltis/MutEnricher .


Assuntos
Genoma Humano , Mutação/genética , Neoplasias/genética , Software , Humanos , Regiões Promotoras Genéticas/genética , Sequenciamento Completo do Genoma
19.
Int J Oral Sci ; 12(1): 22, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737282

RESUMO

A splicing mutation in VPS4B can cause dentin dysplasia type I (DD-I), a hereditary autosomal-dominant disorder characterized by rootless teeth, the etiology of which is genetically heterogeneous. In our study, dental follicle cells (DFCs) were isolated and cultured from a patient with DD-I and compared with those from an age-matched, healthy control. In a previous study, this DD-I patient was confirmed to have a loss-of-function splicing mutation in VPS4B (IVS7 + 46C > G). The results from this study showed that the isolated DFCs were vimentin-positive and CK14-negative, indicating that the isolated cells were derived from the mesenchyme. DFCs harboring the VPS4B mutation had a significantly higher proliferation rate from day 3 to day 8 than control DFCs, indicating that VPS4B is involved in cell proliferation. The cells were then replenished with osteogenic medium to investigate how the VPS4B mutation affected osteogenic differentiation. Induction of osteogenesis, detected by alizarin red and alkaline phosphatase staining in vitro, was decreased in the DFCs from the DD-I patient compared to the control DFCs. Furthermore, we also found that the VPS4B mutation in the DD-I patient downregulated the expression of osteoblast-related genes, such as ALP, BSP, OCN, RUNX2, and their encoded proteins. These outcomes confirmed that the DD-I-associated VPS4B mutation could decrease the capacity of DFCs to differentiate during the mineralization process and may also impair physiological root formation and bone remodeling. This might provide valuable insights and implications for exploring the pathological mechanisms underlying DD-I root development.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/genética , Saco Dentário/citologia , Displasia da Dentina/genética , Displasia da Dentina/fisiopatologia , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Osteogênese/genética , Processamento de RNA/genética , Estudos de Casos e Controles , Diferenciação Celular/genética , Células Cultivadas , Displasia da Dentina/patologia , Humanos , Mutação/genética
20.
Nat Commun ; 11(1): 3808, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732999

RESUMO

Large-scale cancer genomic studies enable the systematic identification of mutations that lead to the genesis and progression of tumors, uncovering the underlying molecular mechanisms and potential therapies. While some such mutations are recurrently found in many tumors, many others exist solely within a few samples, precluding detection by conventional recurrence-based statistical approaches. Integrated analysis of somatic mutations and RNA expression data across 12 tumor types reveals that mutations of cancer genes are usually accompanied by substantial changes in expression. We use topological data analysis to leverage this observation and uncover 38 elusive candidate cancer-associated genes, including inactivating mutations of the metalloproteinase ADAMTS12 in lung adenocarcinoma. We show that ADAMTS12-/- mice have a five-fold increase in the susceptibility to develop lung tumors, confirming the role of ADAMTS12 as a tumor suppressor gene. Our results demonstrate that data integration through topological techniques can increase our ability to identify previously unreported cancer-related alterations.


Assuntos
Proteínas ADAMTS/genética , Adenocarcinoma de Pulmão/genética , Predisposição Genética para Doença/genética , Neoplasias Pulmonares/genética , Animais , Linhagem Celular Tumoral , Biologia Computacional/métodos , Análise de Dados , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Recidiva Local de Neoplasia/genética , Oncogenes/genética
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