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1.
Cancer Sci ; 110(10): 3110-3121, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385398

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies and the fourth leading cause of cancer-related death worldwide. Our previous study showed that EYA4 functioned by suppressing growth of HCC tumor cells, but its molecular mechanism is still not elucidated. Based on the results of gene microassay, EYA4 was inversely correlated with MYCBP and was verified in human HCC tissues by immunohistochemistry and western blot. Overexpressed and KO EYA4 in human HCC cell lines confirmed the negative correlation between EYA4 and MYCBP by qRT-PCR and western blot. Transfected siRNA of MYCBP in EYA4 overexpressed cells and overexpressed MYCBP in EYA4 KO cells could efficiently rescue the proliferation and G2/M arrest effects of EYA4 on HCC cells. Mechanistically, armed with serine/threonine-specific protein phosphatase activity, EYA4 reduced nuclear translocation of ß-catenin by dephosphorylating ß-catenin at Ser552, thereby suppressing the transcription of MYCBP which was induced by ß-catenin/LEF1 binding to the promoter of MYCBP. Clinically, HCC patients with highly expressed EYA4 and poorly expressed MYCBP had significantly longer disease-free survival and overall survival than HCC patients with poorly expressed EYA4 and highly expressed MYCBP. In conclusion, EYA4 suppressed HCC tumor cell growth by repressing MYCBP by dephosphorylating ß-catenin S552. EYA4 combined with MYCBP could be potential prognostic biomarkers in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , beta Catenina/metabolismo , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Serina/metabolismo , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Transcrição Genética , beta Catenina/química
2.
DNA Cell Biol ; 38(10): 1040-1047, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31414895

RESUMO

The helper T cell 9 (Thelper-9, Th9), as a functional subgroup of CD4+T cells, was first discovered in 2008. Th9 cells expressed transcription factor PU.1 and cytokine interleukin-9 (IL-9) characteristically. Recent researches have shown that the differentiation of Th9 cells was coregulated by cytokine transforming growth factor ß, IL-4, and various transcription factors. Th9 cells, as a new player, played an important role in various immune-related diseases, including tumors, inflammatory diseases, parasite infection, and other diseases. In this article, we summarize the related research progress and discuss the possible prospect.


Assuntos
Interleucina-9/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Neoplasias/imunologia , Proteínas Proto-Oncogênicas/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Transativadores/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Diferenciação Celular , Fator de Transcrição GATA3/deficiência , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/imunologia , Regulação da Expressão Gênica , Humanos , Inflamação , Interleucina-4/genética , Interleucina-4/imunologia , Interleucina-9/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Camundongos Knockout , Neoplasias/genética , Neoplasias/patologia , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/imunologia , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/patologia , Transativadores/genética , Fator de Crescimento Transformador beta/genética
3.
DNA Cell Biol ; 38(8): 840-848, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31314587

RESUMO

microRNAs are a class of noncoding RNAs that play important roles in cancer progression. microRNA-183-3p (miR-183-3p) is a novel microRNA that is dysregulated in many kinds of cancers. Our previous studies found high expression and oncologic role of high-mobility group nucleosome binding domain 5 (HMGN5) in prostate cancer. In this study, we found that miR-183-3p was downregulated in prostate cancer cells and primary tissues compared with normal controls. In addition, miR-183-3p expression was negatively correlated with HMGN5 expression. On the basis of bioinformatics predication and quantitative polymerase chain reaction and Western blot verification, it is demonstrated that miR-183-3p regulated HMGN5 expression. Luciferase reporter assay confirmed that miR-183-3p directly targeted the 3'-untranslated region of HMGN5. Interestingly, cell proliferation and migration inhibition and apoptosis induction were also observed in miR-183-3p transfected human prostate cancer VCap and C4-2 cells. Moreover, overexpression of HMGN5 significantly reversed the inhibitory effect on cell proliferation and migration and promoted effect on cell apoptosis by miR-183-3p. Our data suggest that dysfunction of miR-183-3p-HMGN5 axis plays an oncogenic role and can be a therapeutic target for prostate cancer.


Assuntos
Proteínas HMGN/genética , MicroRNAs/genética , Neoplasias da Próstata/genética , Transativadores/genética , Regiões 3' não Traduzidas , Idoso , Apoptose/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Proteínas HMGN/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Transativadores/metabolismo
4.
Yi Chuan ; 41(7): 634-643, 2019 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-31307972

RESUMO

Genetic factors are closely related to the high-altitude adaptation. Several candidate genes have been reported to be significantly associated with high-altitude adaptation. Megakaryocytic leukemia 1 (MKL1) is a transcriptional regulator, which plays crucial roles in the phenotypic modulation of smooth muscle cells. To explore whether MKL1 gene is involved in high-altitude adaptation, we performed genetic association study between MKL1 gene polymorphisms and high-altitude adaptation. We recruited 595 Tibetans from the Qinghai-Tibet plateau and 442 Hans living at low altitude. The SNP rs59098711 locus in the MKL1 gene was genotyped using the MassARRAY assays. We compared the genotypes and allele frequency distributions of rs59098711 between the Hans and Tibetans. The results showed that the genotypes of rs59098711 are significantly different between these two populations (P<0.05). We further compared the genotypes of rs59098711 between Tibetans and other ethnic groups using data from various public databases. We also observed that the genotypes of rs59098711 are significantly different between Tibetans and these other populations (P<0.05). Bioinformatics analyses suggested that rs59098711 could be located at the enhancer region and regulate the expression of the MKL1 gene. Additional study of gene expression data from available public datasets showed that MKL1 gene was up-regulated in a hypobaric hypoxic environment. Our results suggested that the genetic polymorphism rs59098711 locus of the MKL1 gene is associated with high-altitude adaption.


Assuntos
Adaptação Biológica/genética , Altitude , Polimorfismo de Nucleotídeo Único , Transativadores/genética , Humanos , Tibet
5.
Nat Commun ; 10(1): 3049, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296872

RESUMO

The transcription factor p63 is a master regulator of ectoderm development. Although previous studies show that p63 triggers epidermal differentiation in vitro, the roles of p63 in developing embryos remain poorly understood. Here, we use zebrafish embryos to analyze in vivo how p63 regulates gene expression during development. We generate tp63-knock-out mutants that recapitulate human phenotypes and show down-regulated epidermal gene expression. Following p63-binding dynamics, we find two distinct functions clearly separated in space and time. During early development, p63 binds enhancers associated to neural genes, limiting Sox3 binding and reducing neural gene expression. Indeed, we show that p63 and Sox3 are co-expressed in the neural plate border. On the other hand, p63 acts as a pioneer factor by binding non-accessible chromatin at epidermal enhancers, promoting their opening and epidermal gene expression in later developmental stages. Therefore, our results suggest that p63 regulates cell fate decisions during vertebrate ectoderm specification.


Assuntos
Ectoderma/embriologia , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Placa Neural/embriologia , Fosfoproteínas/metabolismo , Transativadores/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas/genética , Diferenciação Celular/genética , Cromatina/metabolismo , Regulação para Baixo , Ectoderma/metabolismo , Embrião não Mamífero , Elementos Facilitadores Genéticos/genética , Epiderme/embriologia , Epiderme/metabolismo , Técnicas de Inativação de Genes , Modelos Animais , Placa Neural/metabolismo , Fosfoproteínas/genética , Ligação Proteica/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transativadores/genética , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética
6.
Genome Biol ; 20(1): 145, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349852

RESUMO

The CRISPR/Cas9 system is unable to edit all targetable genomic sites with full efficiency in vivo. We show that Cas9-mediated editing is more efficient in open chromatin regions than in closed chromatin regions in rice. A construct (Cas9-TV) formed by fusing a synthetic transcription activation domain to Cas9 edits target sites more efficiently, even in closed chromatin regions. Moreover, combining Cas9-TV with a proximally binding dead sgRNA (dsgRNA) further improves editing efficiency up to several folds. The use of Cas9-TV/dsgRNA thus provides a novel strategy for obtaining efficient genome editing in vivo, especially at nuclease-refractory target sites.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , Cromatina/química , Edição de Genes , Ativação Transcricional , Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Oryza/genética , RNA/genética , Transativadores/genética
7.
Gastroenterology ; 157(3): 838-850.e6, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31163177

RESUMO

BACKGROUND & AIMS: Little is known about mechanisms of perineural invasion (PNI) by pancreatic ductal adenocarcinomas (PDAs) or other tumors. Annexin A2 (ANXA2) regulates secretion of SEMA3D, an axon guidance molecule, which binds and activates the receptor PLXND1 to promote PDA invasion and metastasis. We investigated whether axon guidance molecules promote PNI and metastasis by PDA cells in mice. METHODS: We performed studies in a dorsal root ganglion (DRG) invasion system, wild-type C57BL/6 mice (controls), mice with peripheral sensory neuron-specific disruption of PlxnD1 (PLAC mice), LSL-KRASG12D/+;LSL-TP53R172H/+;PDX-1-CRE+/+ (KPC) mice, and KPC mice crossed with ANXA2-knockout mice (KPCA mice). PDA cells were isolated from KPC mice and DRG cells were isolated from control mice. Levels of SEMA3D or ANXA2 were knocked down in PDA cells with small hairpin and interfering RNAs and cells were analyzed by immunoblots in migration assays, with DRGs and with or without antibodies against PLXND1. PDA cells were injected into the pancreas of control and PLAC mice, growth of tumors was assessed, and tumor samples were analyzed by histology. DRG cells were incubated with SEMA3D and analyzed by live imaging. We measured levels of SEMA3D and PLXND1 in PDA specimens from patients with PNI and calculated distances between tumor cells and nerves. RESULTS: DRG cells increase the migration of PDC cells in invasion assays; knockdown of SEMA3D in PDA cells or antibody blockade of PLXND1 on DRG cells reduced this invasive activity. In mice, orthotopic tumors grown from PDA cells with knockdown of SEMA3D, and in PLAC mice, orthotopic tumors grown from PDA cells, had reduced innervation and formed fewer metastases than orthotopic tumors grown from PDA cells in control mice. Increased levels of SEMA3D and PLXND1 in human PDA specimens associated with PNI. CONCLUSIONS: DRG cells increase the migratory and invasive activities of pancreatic cancer cells, via secretion of SEMA3D by pancreatic cells and activation of PLXND1 on DRGs. Knockdown of SEMA3D and loss of neural PLXND1 reduces innervation of orthotopic PDAs and metastasis in mice. Increased levels of SEMA3D and PLXND1 in human PDA specimens associated with PNI. Strategies to disrupt the axon guidance pathway mediated by SEMA3D and PLXND1 might be developed to slow progression of PDA.


Assuntos
Anexina A2/metabolismo , Orientação de Axônios , Carcinoma Ductal Pancreático/metabolismo , Movimento Celular , Gânglios Espinais/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/metabolismo , Semaforinas/metabolismo , Animais , Anexina A2/deficiência , Anexina A2/genética , Orientação de Axônios/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/secundário , Comunicação Celular , Gânglios Espinais/patologia , Regulação Neoplásica da Expressão Gênica , Genes p53 , Genes ras , Predisposição Genética para Doença , Proteínas de Homeodomínio/genética , Humanos , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Invasividade Neoplásica , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Crescimento Neuronal , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Semaforinas/genética , Transdução de Sinais , Transativadores/genética , Células Tumorais Cultivadas
8.
Microbiol Res ; 223-225: 137-143, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178047

RESUMO

Pseudomonas aeruginosa is an opportunistic pathogen with high clinical relevance for hospital infections of patients. Accumulating DNA sequencing results of clinical P. aeruginosa isolates have revealed frequent mutations in lasR gene, which encodes the highest arches component of quorum-sensing system (QS). We analyzed the sequencing data of lasR gene from a large collection of cystic fibrosis (CF) P. aeruginosa isolates. Our systematical analyses revealed that single nucleotide polymorphisms (SNPs) selection in lasR gene were largely constrained by codon-usage frequency. As a whole, SNP-substituted codons encoding unconserved amino acid resulted in unfavored codons with relatively low codon-usage frequency, while those associating with conserved amino acid were not strictly regulated in such way. These SNPs substitutions gives rise to diverse functional LasR isoforms and contributes to the relative growth fitness of recombinant lasR variant strains. Our survey reveals a novel pattern of SNPs selections in lasR gene of CF isolates. Our findings could be served as a powerful resource for understanding adaptive mechanism of clinical isolates under environmental constrains and developing anti-bacteria drugs for CF patients.


Assuntos
Proteínas de Bactérias/genética , Códon/genética , Fibrose Cística/microbiologia , Polimorfismo de Nucleotídeo Único/genética , Pseudomonas aeruginosa/genética , Transativadores/genética , Sequência de Aminoácidos , Regulação Bacteriana da Expressão Gênica , Isoformas de Proteínas , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/patogenicidade , Percepção de Quorum/genética , Alinhamento de Sequência , Análise de Sequência de DNA
9.
PLoS Genet ; 15(6): e1008233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31233504

RESUMO

Pathogenic Salmonella strains that cause gastroenteritis are able to colonize and replicate within the intestines of multiple host species. In general, these strains have retained an ability to form the rdar morphotype, a resistant biofilm physiology hypothesized to be important for Salmonella transmission. In contrast, Salmonella strains that are host-adapted or even host-restricted like Salmonella enterica serovar Typhi, tend to cause systemic infections and have lost the ability to form the rdar morphotype. Here, we investigated the rdar morphotype and CsgD-regulated biofilm formation in two non-typhoidal Salmonella (NTS) strains that caused invasive disease in Malawian children, S. Typhimurium D23580 and S. Enteritidis D7795, and compared them to a panel of NTS strains associated with gastroenteritis, as well as S. Typhi strains. Sequence comparisons combined with luciferase reporter technology identified key SNPs in the promoter region of csgD that either shut off biofilm formation completely (D7795) or reduced transcription of this key biofilm regulator (D23580). Phylogenetic analysis showed that these SNPs are conserved throughout the African clades of invasive isolates, dating as far back as 80 years ago. S. Typhi isolates were negative for the rdar morphotype due to truncation of eight amino acids from the C-terminus of CsgD. We present new evidence in support of parallel evolution between lineages of nontyphoidal Salmonella associated with invasive disease in Africa and the archetypal host-restricted invasive serovar; S. Typhi. We hypothesize that the African invasive isolates are becoming human-adapted and 'niche specialized' with less reliance on environmental survival, as compared to gastroenteritis-causing isolates.


Assuntos
Evolução Biológica , Gastroenterite/genética , Infecções por Salmonella/genética , Salmonella typhimurium/genética , África/epidemiologia , Biofilmes/crescimento & desenvolvimento , Criança , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Infecções por Salmonella/microbiologia , Infecções por Salmonella/transmissão , Salmonella typhimurium/patogenicidade , Transativadores/genética
10.
PLoS Genet ; 15(6): e1008193, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31242181

RESUMO

Mechanisms for highly efficient chromosome-associated equal segregation, and for maintenance of steady state copy number, are at the heart of the evolutionary success of the 2-micron plasmid as a stable multi-copy extra-chromosomal selfish DNA element present in the yeast nucleus. The Flp site-specific recombination system housed by the plasmid, which is central to plasmid copy number maintenance, is regulated at multiple levels. Transcription of the FLP gene is fine-tuned by the repressor function of the plasmid-coded partitioning proteins Rep1 and Rep2 and their antagonist Raf1, which is also plasmid-coded. In addition, the Flp protein is regulated by the host's post-translational modification machinery. Utilizing a Flp-SUMO fusion protein, which functionally mimics naturally sumoylated Flp, we demonstrate that the modification signals ubiquitination of Flp, followed by its proteasome-mediated degradation. Furthermore, reduced binding affinity and cooperativity of the modified Flp decrease its association with the plasmid FRT (Flp recombination target) sites, and/or increase its dissociation from them. The resulting attenuation of strand cleavage and recombination events safeguards against runaway increase in plasmid copy number, which is deleterious to the host-and indirectly-to the plasmid. These results have broader relevance to potential mechanisms by which selfish genomes minimize fitness conflicts with host genomes by holding in check the extra genetic load they pose.


Assuntos
DNA Nucleotidiltransferases/genética , Sequências Repetitivas de Ácido Nucleico/genética , Proteína SUMO-1/genética , Transcrição Genética , Segregação de Cromossomos/genética , Variações do Número de Cópias de DNA/genética , Replicação do DNA/genética , Genoma Fúngico/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ligação Proteica/genética , Processamento de Proteína Pós-Traducional/genética , Proteínas Proto-Oncogênicas c-raf/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Sumoilação/genética , Transativadores/genética
11.
Nat Commun ; 10(1): 2723, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222014

RESUMO

Non-genetic drug resistance is increasingly recognised in various cancers. Molecular insights into this process are lacking and it is unknown whether stable non-genetic resistance can be overcome. Using single cell RNA-sequencing of paired drug naïve and resistant AML patient samples and cellular barcoding in a unique mouse model of non-genetic resistance, here we demonstrate that transcriptional plasticity drives stable epigenetic resistance. With a CRISPR-Cas9 screen we identify regulators of enhancer function as important modulators of the resistant cell state. We show that inhibition of Lsd1 (Kdm1a) is able to overcome stable epigenetic resistance by facilitating the binding of the pioneer factor, Pu.1 and cofactor, Irf8, to nucleate new enhancers that regulate the expression of key survival genes. This enhancer switching results in the re-distribution of transcriptional co-activators, including Brd4, and provides the opportunity to disable their activity and overcome epigenetic resistance. Together these findings highlight key principles to help counteract non-genetic drug resistance.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Transativadores/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência de RNA , Análise de Célula Única , Transativadores/genética , Transativadores/metabolismo , Transcrição Genética/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
12.
BMC Med Genet ; 20(1): 84, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101089

RESUMO

BACKGROUND: Progressive bilateral sensorineural deafness in postlingual period may be linked to many different etiologies including genetic factors. Identification of the exact deafness cause may, therefore, be quite challenging. Here we present a family with late-onset hearing loss as an autosomal dominant trait caused by a novel EYA4 mutation. CASE PRESENTATION: Forty-four years old female proband clinically investigated for progressive hearing loss and occasional dizziness with positive family history for deafness was subject to molecular-genetic testing. Patient's DNA sample was analyzed by whole exome sequencing. We identified a novel missense variant c.804G > C located at the last base pair of exon 10 in EYA4. Candidate variant was confirmed by Sanger sequencing in the proband and her family members. In silico prediction tools and co-segregation analysis were used to indicate pathogenicity of the identified variant. To confirm our hypothesis, we performed minigene assay to demonstrate if the transcript of exon 10 in EYA4 is present. We provide evidence that this mutation in vitro compromises donor site functionality and causes exon 10 skipping and frameshift that most likely results in nonsense-mediated mRNA decay. The onset of moderate to severe hearing loss in the family ranged from 10 to 40 years. The normal cardiac phenotype was confirmed by ECG and echocardiography. CONCLUSIONS: We identified a novel EYA4 mutation associated with adult-onset autosomal dominant sensorineural hearing loss. This report extends the knowledge of spectrum of EYA4 mutations and demonstrates the pathogenicity of a variant affecting specific position in the gene. A comprehensive review of known EYA4 mutations is also given and their impact on cardiac phenotype is discussed. Our findings highlight the importance of genetic testing and complex clinical assessment in patients with familial progressive hearing loss.


Assuntos
Genes Dominantes , Perda Auditiva/genética , Transativadores/genética , Idade de Início , Feminino , Humanos , Pessoa de Meia-Idade , Eslováquia
13.
J Med Food ; 22(5): 444-450, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084542

RESUMO

Studies have identified the potential of chemopreventive effects of sulforaphane (SFN); however, the underlying mechanisms of its effect on breast cancer require further elucidation. This study investigated the anticancer effects of SFN that specifically induces G1/S arrest in breast ductal carcinoma (ZR-75-1) cells. The proliferation of the cancer cells after treatment with SFN was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. DNA content and cell cycle status were analyzed through flow cytometry. Our results demonstrated the inhibition of growth in ZR-75-1 cells upon SFN exposure. In addition, SERTAD1 (SEI-1) caused the accumulation of SFN-treated G1/S-phase cells. The downregulation of SEI-1, cyclin D2, and histone deacetylase 3 suggested that in addition to the identified effects of SFN against breast cancer prevention, it may also exert antitumor activities in established breast cancer cells. In conclusion, SFN can inhibit growth of and induce cell cycle arrest in cancer cells, suggesting its potential role as an anticancer agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Isotiocianatos/farmacologia , Proteínas Nucleares/genética , Transativadores/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D2/genética , Ciclina D2/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Extratos Vegetais/farmacologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transativadores/metabolismo , Verduras/química
14.
Artif Cells Nanomed Biotechnol ; 47(1): 2003-2009, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31106596

RESUMO

Hepatitis B virus is one of the main causes of hepatitis and hepatocellular carcinoma (HCC). Hepatitis B virus-encoded X protein (HBx) has been shown to be involved in many aspects of the pathogenicity of liver diseases. Orexin A is a small peptide produced in the hippocampus. Orexin A and its receptor have become important therapeutic targets for certain metabolic disorders. In this study, we show that orexin A has a protective role against HBx-induced cytotoxicity and inflammation in hepatocytes. The ectopic expression of HBx in hepatocytes reduces orexin A receptor 1 (OX1R) expression. When orexin A is added to the cells, it mitigates HBx-induced oxidative stress indicator 4-hydroxynonenal (4-HNE) and reactive oxygen species (ROS) as well the NADPH subunit NADPH oxidase 4 (NOX-4). Orexin A also ameliorates HBx-mediated mitochondrial membrane potential and adenosine triphosphate (ATP) reduction. Moreover, orexin A significantly inhibits HBx-induced production of pro-inflammatory cytokines including interleukin 8 (IL-8), tumour necrosis factor α (TNF-α) and chemokine ligand 2 (CXCL2). The presence of orexin A ameliorates HBx-induced lactate dehydrogenase (LDH) release, indicating that it could protect hepatocytes from cytotoxicity. Mechanistically, we found that orexin A suppresses c-Jun N-terminal kinase (JNK) phosphorylation, accumulation of nuclear factor-κB (NF-κB) protein p65 in nuclei, and NF-κB promoter activity, suggesting that orexin A suppresses JNK and NF-κB pathway activation. In conclusion, our study demonstrates that orexin A peptide possesses a protective role against HBx-mediated cytotoxicity and inflammation in hepatocytes.


Assuntos
Citoproteção/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Orexinas/farmacologia , Transativadores/metabolismo , Linhagem Celular , Citocinas/metabolismo , Ativação Enzimática/efeitos dos fármacos , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/efeitos dos fármacos , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transativadores/genética
15.
Cell Physiol Biochem ; 52(6): 1503-1516, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31112017

RESUMO

BACKGROUND/AIMS: Zinc Finger Protein 281 (ZNF281) was recently identified as a novel oncogene in several human carcinomas. However, the clinical significance of ZNF281 in colorectal cancer (CRC) and the molecular mechanisms by which ZNF281 promotes the growth and metastasis of CRC remain unknown. METHODS: ZNF281 expression in CRC tissues was assessed, and the outcomes were analyzed to determine the clinical importance of ZNF281 expression. Cell Transwell assays and a wound healing assay were performed to assess the effects of ZNF281 on CRC cell migration and invasion in vitro. Western blotting was applied to analyze the potential mechanisms. RESULTS: ZNF281 mRNA and protein levels were significantly increased in CRC tissues compared with normal colon tissues, and high ZNF281 expression was associated with advanced T stage, N stage, TNM stage and differentiation. Therefore, ZNF281 expression might be an independent prognostic indicator in CRC patients. Moreover, knockdown of ZNF281 expression suppressed cell proliferation, migration and invasion by inhibiting the Wnt/ß-catenin pathway. CONCLUSION: Our study indicates that ZNF281 plays a critical role in the progression and metastasis of CRC and could represent a potential therapeutic target for CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Transativadores/metabolismo , Idoso , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Neoplasias Colorretais/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , RNA Interferente Pequeno/genética , Transativadores/antagonistas & inibidores , Transativadores/genética , Regulação para Cima , Via de Sinalização Wnt , beta Catenina/metabolismo
16.
Arch Virol ; 164(8): 2091-2106, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31139938

RESUMO

Beak and feather disease virus (BFDV) belongs to the family Circoviridae. A rolling-circle replication strategy based on a replication-associated protein (Rep) has been proposed for BFDV. The Rep gene of BFDV was expressed and purified, and it was shown to cleave short oligonucleotides containing the conserved nonanucleotide sequence found in the replication origin of circoviruses. This endonuclease activity was most efficient in the presence of the divalent metal ions Mg2+ and Mn2+. Rep proteins containing mutation in the ATPase/GTPase motifs and the 14FTLNN18, 61KKRLS65, 89YCSK92, and 170GKS172 motifs lacked endonuclease activity. The endonuclease activity was not affected by ATPase inhibitors, with the exception of N-ethylmaleimide (NEM), or by GTPase inhibitors, but it was decreased by treatment with the endonuclease inhibitor L-742001. Both the ATPase and GTPase activities were decreased by site-directed mutagenesis and deletion of the ATPase/GTPase and endonuclease motifs. The Rep protein was able to bind a double-stranded DNA fragment of P36 (dsP36) containing the stem-loop structure of the replication origin of BFDV. All of the Rep mutant proteins showed reduced ability to bind this fragment, suggesting that all the ATPase/GTPase and endonuclease motifs are involved in the binding. Other than NEM, all ATPase, GTPase, and endonuclease inhibitors inhibited the binding of the Rep protein to the dsP36 fragment. This is the first report describing the endonuclease activity of the Rep protein of BFDV.


Assuntos
Circovirus/genética , Replicação do DNA/genética , Endonucleases/genética , Replicação Viral/genética , Adenosina Trifosfatases/genética , Infecções por Circoviridae/virologia , DNA Helicases/genética , DNA Viral/genética , GTP Fosfo-Hidrolases/genética , Origem de Replicação/genética , Transativadores/genética
17.
Doc Ophthalmol ; 139(1): 45-57, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30945053

RESUMO

PURPOSE: The aim of this study was to examine the ophthalmological characteristics and genotypes of patients with congenital retinal pathologies, who display a bull's-eye maculopathy in the fundus, along with a negative scotopic electroretinogram. METHODS: We analysed the results of five patients showing both a bull's-eye maculopathy, as well as a negative scotopic ERG evoked by a bright flash. Their median age was 39 years (range 11-63 years): three males and two females. All underwent a comprehensive examination with determination of distant visual acuity (ETDRS) and recording of the full-field ERG (scotopic and photopic). Fundus, OCT, and FAF images were obtained, the kinetic visual field was determined, and colour vision (D-15) was tested in most patients. Targeted gene panel sequencing was performed on peripheral blood. RESULTS: One patient carried a homozygous ABCA4 mutation and an additional heterozygous variant in CRX. Two of the five patients were shown to have a heterozygous mutation in the CRX gene, one of whom had an additional heterozygous ABCA4 mutation. Two patients had the common heterozygous mutation c.2413G>A;p.Arg838His in GUCY2D. In all of the patients, there was a reduction in the amplitude of the b-wave with a regular a-wave amplitude in the scotopic bright-flash ERG. CONCLUSIONS: The five patients with bull's-eye maculopathy along with a negative ERG had differing genotypes. Mutations were found in the CRX gene (2 patients), the ABCA4 gene (1 patient), and the GUCY2D gene (2 patients).


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Guanilato Ciclase/genética , Proteínas de Homeodomínio/genética , Degeneração Macular/genética , Degeneração Macular/fisiopatologia , Mutação , Receptores de Superfície Celular/genética , Retina/fisiopatologia , Transativadores/genética , Adulto , Criança , Análise Mutacional de DNA , Eletrorretinografia , Feminino , Angiofluoresceinografia , Humanos , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Visão Noturna/fisiologia , Estimulação Luminosa , Acuidade Visual/fisiologia , Adulto Jovem
18.
Nat Microbiol ; 4(7): 1114-1119, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30936487

RESUMO

Social interactions play an increasingly recognized key role in bacterial physiology1. One of the best studied is quorum sensing (QS), a mechanism by which bacteria sense and respond to the status of cell density2. While QS is generally deemed crucial for bacterial survival, QS-dysfunctional mutants frequently arise in in vitro culture. This has been explained by the fitness cost an individual mutant, a 'quorum cheater', saves at the expense of the community3. QS mutants are also often isolated from biofilm-associated infections, including cystic fibrosis lung infection4, as well as medical device infection and associated bacteraemia5-7. However, despite the frequently proposed use of QS blockers to control virulence8, the mechanisms underlying QS dysfunctionality during infection have remained poorly understood. Here, we show that in the major human pathogen Staphylococcus aureus, quorum cheaters arise exclusively in biofilm infection, while in non-biofilm-associated infection there is a high selective pressure to maintain QS control. We demonstrate that this infection-type dependence is due to QS-dysfunctional bacteria having a significant survival advantage in biofilm infection because they form dense and enlarged biofilms that provide resistance to phagocyte attacks. Our results link the benefit of QS-dysfunctional mutants in vivo to biofilm-mediated immune evasion, thus to mechanisms that are specific to the in vivo setting. Our findings explain why QS mutants are frequently isolated from biofilm-associated infections and provide guidance for the therapeutic application of QS blockers.


Assuntos
Biofilmes/crescimento & desenvolvimento , Infecções Relacionadas a Cateter/microbiologia , Evasão da Resposta Imune , Leucócitos/imunologia , Percepção de Quorum/fisiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Animais , Proteínas de Bactérias/genética , Infecções Relacionadas a Cateter/imunologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Mutação , Percepção de Quorum/genética , Infecções Estafilocócicas/imunologia , Infecções Cutâneas Estafilocócicas/imunologia , Infecções Cutâneas Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/fisiologia , Transativadores/genética
19.
Plant Mol Biol ; 100(6): 571-578, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30953277

RESUMO

KEY MESSAGE: A mutation in the nuclear localization signal of squamosa promoter binding like-protein 9 (SPL9) delays vegetative phase change by disrupting its nuclear localization. The juvenile-to-adult phase transition is a critical developmental process in plant development, and it is regulated by a decrease in miR156/157 and a corresponding increase in their targets, squamosa promoter binding protein-like (SPL) genes. SPL proteins contain a conserved SBP domain with putative nuclear localization signals (NLSs) at their C-terminals. Some SPLs promote vegetative phase change by promoting miR172 expression, but the function of nuclear localization signals in those SPLs remains unknown. Here, we identified a loss-of-function mutant, which we named del6, with delayed vegetative phase change phenotypes in a forward genetic screen. Map-based cloning, the whole genome resequencing, and allelic complementation test demonstrate that a G-to-A substitution in the SPL9 gene is responsible for the delayed vegetative phase change phenotypes. In del6, the mutation causes a substitution of the glutamine (Gln) for the conserved basic amino acid arginine (Arg) in the NLS of the SBP domain, and disrupts the normal nuclear localization and function of SPL9. Therefore, our work demonstrates that the NLSs in the SBP domain of SPL9 are indispensable for its nuclear localization and normal function in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Sinais de Localização Nuclear , Regiões Promotoras Genéticas , Transativadores/genética , Transativadores/fisiologia , Alelos , Arginina/química , Proteínas de Transporte/metabolismo , Núcleo Celular/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Vetores Genéticos , Genoma de Planta , Glutamina/química , MicroRNAs/genética , Mutação , Fenótipo , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas
20.
ACS Appl Mater Interfaces ; 11(17): 15332-15343, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30950609

RESUMO

In this study, we use Escherichia coli as a model to investigate the antimicrobial mechanism of a film made of a copolymer based on monomethylether poly(ethylene glycol), methyl methacrylate, and 2-dimethyl(aminoethyl) methacrylate, whose surface is active towards Gram-negative and Gram-positive bacteria. The polymer contains not quaternized amino groups that can generate a charged surface by protonation when in contact with water. For this purpose, we adopted a dual strategy based on the analysis of cell damage caused by contact with the polymer surface and on the evaluation of the cell response to the surface toxic action. The lithic effect on the protoplasts of E. coli showed that the polymer surface can affect the structure of cytoplasmic membranes, while assays of calcein leakage from large unilamellar vesicles at different phospholipid compositions indicated that action on membranes does not need a functionally active cell. On the other hand, the significant increase in sensitivity to actinomycin D demonstrates that the polymer interferes also with the structure of the outer membrane, modifying its permeability. The study on gene expression, based on the analysis of the transcripts in a temporal window where the contact with the polymer is not lethal and the damage is reversible, showed that some key genes of the synthesis and maintenance of the outer membrane structure ( fabR, fadR, fabA, waaA, waaC, kdsA, pldA, and pagP), as well as regulators of cellular response to oxidative stress ( soxS), are more expressed when bacteria are exposed to the polymer surface. All together these results identified the outer membrane as the main cellular target of the antimicrobial surface and indicated a specific cellular response to damage, providing more information on the antimicrobial mechanism. In this perspective, data reported here could play a pivotal role in a microbial growth control strategy based not only on the structural improvements of the materials but also on the possibility of intervening on the cellular pathways involved in the contrast reaction to these and other polymers with similar mechanisms.


Assuntos
Antibacterianos/metabolismo , Materiais Revestidos Biocompatíveis/química , Polímeros/química , Aciltransferases/genética , Aciltransferases/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Materiais Revestidos Biocompatíveis/farmacologia , Dactinomicina/química , Dactinomicina/metabolismo , Dactinomicina/farmacologia , Condutividade Elétrica , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Polietilenoglicóis/química , Polímeros/farmacologia , Polimetil Metacrilato/química , Propriedades de Superfície , Transativadores/genética , Transativadores/metabolismo , Lipossomas Unilamelares/química , Lipossomas Unilamelares/metabolismo
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