Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 211
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(26): e2320835121, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38900797

RESUMO

Upper aerodigestive squamous cell carcinoma (UASCC) is a common and aggressive malignancy with few effective therapeutic options. Here, we investigate amino acid metabolism in this cancer, surprisingly noting that UASCC exhibits the highest methionine level across all human cancers, driven by its transporter LAT1. We show that LAT1 is also expressed at the highest level in UASCC, transcriptionally activated by UASCC-specific promoter and enhancers, which are directly coregulated by SCC master regulators TP63/KLF5/SREBF1. Unexpectedly, unbiased bioinformatic screen identifies EZH2 as the most significant target downstream of the LAT1-methionine pathway, directly linking methionine metabolism to epigenomic reprogramming. Importantly, this cascade is indispensable for the survival and proliferation of UASCC patient-derived tumor organoids. In addition, LAT1 expression is closely associated with cellular sensitivity to inhibition of the LAT1-methionine-EZH2 axis. Notably, this unique LAT1-methionine-EZH2 cascade can be targeted effectively by either pharmacological approaches or dietary intervention in vivo. In summary, this work maps a unique mechanistic cross talk between epigenomic reprogramming with methionine metabolism, establishes its biological significance in the biology of UASCC, and identifies a unique tumor-specific vulnerability which can be exploited both pharmacologically and dietarily.


Assuntos
Carcinoma de Células Escamosas , Regulação Neoplásica da Expressão Gênica , Transportador 1 de Aminoácidos Neutros Grandes , Metionina , Metionina/metabolismo , Humanos , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Linhagem Celular Tumoral , Epigênese Genética , Epigenômica/métodos , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Camundongos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Proliferação de Células , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Reprogramação Celular/genética
2.
Nature ; 579(7797): 118-122, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103178

RESUMO

It has long been assumed that lifespan and healthspan correlate strongly, yet the two can be clearly dissociated1-6. Although there has been a global increase in human life expectancy, increasing longevity is rarely accompanied by an extended healthspan4,7. Thus, understanding the origin of healthy behaviours in old people remains an important and challenging task. Here we report a conserved epigenetic mechanism underlying healthy ageing. Through genome-wide RNA-interference-based screening of genes that regulate behavioural deterioration in ageing Caenorhabditis elegans, we identify 59 genes as potential modulators of the rate of age-related behavioural deterioration. Among these modulators, we found that a neuronal epigenetic reader, BAZ-2, and a neuronal histone 3 lysine 9 methyltransferase, SET-6, accelerate behavioural deterioration in C. elegans by reducing mitochondrial function, repressing the expression of nuclear-encoded mitochondrial proteins. This mechanism is conserved in cultured mouse neurons and human cells. Examination of human databases8,9 shows that expression of the human orthologues of these C. elegans regulators, BAZ2B and EHMT1, in the frontal cortex increases with age and correlates positively with the progression of Alzheimer's disease. Furthermore, ablation of Baz2b, the mouse orthologue of BAZ-2, attenuates age-dependent body-weight gain and prevents cognitive decline in ageing mice. Thus our genome-wide RNA-interference screen in C. elegans has unravelled conserved epigenetic negative regulators of ageing, suggesting possible ways to achieve healthy ageing.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Epigênese Genética , Envelhecimento Saudável/genética , Histona-Lisina N-Metiltransferase/metabolismo , Fatores Genéricos de Transcrição/metabolismo , Envelhecimento/genética , Animais , Proteínas de Caenorhabditis elegans/genética , Cognição , Disfunção Cognitiva , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/química , Histonas/metabolismo , Humanos , Longevidade/genética , Lisina/metabolismo , Masculino , Memória , Metilação , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Proteínas/genética , Interferência de RNA , Aprendizagem Espacial , Fatores Genéricos de Transcrição/deficiência , Fatores Genéricos de Transcrição/genética
3.
Proc Natl Acad Sci U S A ; 120(6): e2221637120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716376

RESUMO

Lipids establish the specialized thylakoid membrane of chloroplast in eukaryotic photosynthetic organisms, while the molecular basis of lipid transfer from other organelles to chloroplast remains further elucidation. Here we revealed the structural basis of Arabidopsis Sec14 homology proteins AtSFH5 and AtSFH7 in transferring phosphatidic acid (PA) from endoplasmic reticulum (ER) to chloroplast, and whose function in regulating the lipid composition of chloroplast and thylakoid development. AtSFH5 and AtSFH7 localize at both ER and chloroplast, whose deficiency resulted in an abnormal chloroplast structure and a decreased thickness of stacked thylakoid membranes. We demonstrated that AtSFH5, but not yeast and human Sec14 proteins, could specifically recognize and transfer PA in vitro. Crystal structures of the AtSFH5-Sec14 domain in complex with L-α-phosphatidic acid (L-α-PA) and 1,2-dipalmitoyl-sn-glycero-3-phosphate (DPPA) revealed that two PA ligands nestled in the central cavity with different configurations, elucidating the specific binding mode of PA to AtSFH5, different from the reported phosphatidylethanolamine (PE)/phosphatidylcholine (PC)/phosphatidylinositol (PI) binding modes. Quantitative lipidomic analysis of chloroplast lipids showed that PA and monogalactosyldiacylglycerol (MGDG), particularly the C18 fatty acids at sn-2 position in MGDG were significantly decreased, indicating a disrupted ER-to-plastid (chloroplast) lipid transfer, under deficiency of AtSFH5 and AtSFH7. Our studies identified the role and elucidated the structural basis of plant SFH proteins in transferring PA between organelles, and suggested a model for ER-chloroplast interorganelle phospholipid transport from inherent ER to chloroplast derived from endosymbiosis of a cyanobacteriumproviding a mechanism involved in the adaptive evolution of cellular plastids.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Cloroplastos , Ácidos Fosfatídicos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Ácidos Fosfatídicos/metabolismo , Tilacoides/metabolismo
4.
Eur J Clin Invest ; 53(12): e14072, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37507843

RESUMO

BACKGROUND: Anaemia of chronic disease (ACD) is the second most common type of anaemia and lacks an effective treatment. Patients with anaemia are reported to have altered gut microbial profiles, which may affect erythropoiesis. Here, we investigated the gut microbial features of patients with ACD and determined whether regulating gut microbiota using washed microbiota transplantation (WMT) was effective in treating ACD. METHODS: We compared the gut microbiota profile of patients with ACD and healthy controls, evaluated the efficacy of WMT on haematological parameters in the patients, and analysed the alterations in gut microbiota after WMT treatment. RESULTS: Patients with ACD had lower gut microbial richness, and differences in microbial composition and function, relative to healthy controls. Additionally, the relative abundances of two butyrate-producing genera Lachnospiraceae NK4A136 group and Butyricicoccus, were positively correlated with the haemoglobin (HGB) level and lower in patients with ACD than controls. WMT significantly increased HGB levels in patients with ACD. After the first, second and third WMT rounds, normal HGB levels were restored in 27.02%, 27.78% and 36.37% (all p < .05) of patients with ACD, respectively. Moreover, WMT significantly increased the abundance of butyrate-producing genera and downregulated gut microbial functions that were upregulated in patients with ACD. CONCLUSIONS: Patients with ACD exhibited differences in gut microbial composition and function relative to healthy controls. WMT is an effective treatment for ACD that reshapes gut microbial composition, restores butyrate-producing bacteria and regulates the functions of gut microbiota.


Assuntos
Anemia , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiologia , Butiratos , Doença Crônica , Anemia/terapia , Hemoglobinas
5.
Catheter Cardiovasc Interv ; 102(4): 743-750, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37493466

RESUMO

BACKGROUND: Conduction disturbances requiring permanent pacemaker implantation (PPI) are common following transcatheter aortic valve replacement (TAVR). There were conflicting data regarding the impact of new PPI on clinical outcomes after TAVR. OBJECTIVES: The study sought to evaluate the impact of new PPI on clinical outcomes in patients undergoing TAVR. METHODS: This study was a retrospective analysis of prospectively collected data. Data were from 210 consecutive patients without prior PPI who underwent TAVR due to severe symptomatic aortic stenosis at our center between June 2018 and July 2020. Clinical, echocardiographic, and pacing data were assessed at 30-day, 1- and 2-year follow-up. RESULTS: New PPI was required in 35 (16.7%) patients within 30 days after TAVR. The median time from TAVR to PPI was 3 days. The most common indication for PPI was high-degree or complete atrioventricular block. The median follow-up was 798.0 (interquartile range, 669.0-1115.0) days. There were no differences in all-cause mortality (adjusted hazard ratio [HR]: 1.18; 95% confidence interval [CI]: 0.85-2.36; p = 0.415) and cardiovascular mortality (adjusted HR: 0.92; 95% CI: 0.57-1.89; p = 0.609) between groups. However, PPI group had a higher risk of heart failure (HF) rehospitalization (adjusted HR: 1.53; 95% CI: 1.26-2.28; p = 0.027). Echocardiography showed no significant improvement of LVEF over time in patients with PPI. At the latest follow-up, 31.3% of patients exhibited low (≤10%) pacing burdens, whereas 28.1% of patients had near constant (>90%) right ventricular pacing. CONCLUSIONS: New PPI within 30 days following TAVR was not associated with an increased risk of all-cause or cardiovascular mortality. However, patients with PPI had a higher risk of HF rehospitalization and lack of LVEF improvement.


Assuntos
Estenose da Valva Aórtica , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Prognóstico , Estudos Retrospectivos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estimulação Cardíaca Artificial/efeitos adversos , Resultado do Tratamento , Fatores de Risco , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia
6.
BMC Cardiovasc Disord ; 23(1): 330, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386379

RESUMO

BACKGROUND: Evidence about safety and efficacy of transcatheter aortic valve replacement (TAVR) with the Venus A-Valve system (Venus Medtech, Hangzhou, China) remains limited for patients with pure native aortic regurgitation (PNAR). OBJECTIVES: The single-center study sought to report the one-year clinical outcomes of the Venus A-Valve in the treatment of PNAR. METHODS: This study was a retrospective analysis of prospectively collected data. Data was from all consecutive patients who had PNAR and underwent TAVR with the Venus A-Valve system at our center from July 2020 and June 2021. Procedural and clinical outcomes up to one year were analyzed using Valve Academic Research Consortium-2 criteria. RESULTS: A total of 45 consecutive patients with PNAR underwent transfemoral TAVR with the Venus A-Valve system. The Mean age was 73.5 ± 5.5 years and 26.7% were female. All the TAVR procedures were performed via transfemoral access. Implantations were successful in 44 cases (97.8%). Only one patient was converted to surgical aortic valve replacement. No patient died intraoperatively. No second valve was implanted. In-hospital mortality rate was 2.3%. The one-year all-cause mortality rate was 4.7% without cardiovascular related death. No patient had moderate or severe paravalvular leakage during follow-up. At one year, the mean pressure gradient was 8.8 ± 0.9 mmHg, and left ventricular ejection fraction increased to 61.5 ± 3.6%. CONCLUSIONS: This single-center study demonstrated the safety and efficacy of transfemoral TAVR with the Venus A-Valve in the treatment of patients with PNAR.


Assuntos
Insuficiência da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Feminino , Idoso , Masculino , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
7.
J Proteome Res ; 21(1): 200-208, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34846153

RESUMO

Deintensification therapy for human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV(+) OPSCC) is under active investigation. An adaptive treatment approach based on molecular stratification could identify high-risk patients predisposed to recurrence and better select for appropriate treatment regimens. Collectively, 40 HPV(+) OPSCC FFPE samples (20 disease-free, 20 recurrent) were surveyed using mass spectrometry-based proteomic analysis via data-independent acquisition to obtain fold change and false discovery differences. Ten-year overall survival was 100.0 and 27.7% for HPV(+) disease-free and recurrent cohorts, respectively. Of 1414 quantified proteins, 77 demonstrated significant differential expression. Top enriched functional pathways included those involved in programmed cell death (73 proteins, p = 7.43 × 10-30), apoptosis (73 proteins, p = 5.56 × 10-9), ß-catenin independent WNT signaling (47 proteins, p = 1.45 × 10-15), and Rho GTPase signaling (69 proteins, p = 1.09 × 10-5). PFN1 (p = 1.0 × 10-3), RAD23B (p = 2.9 × 10-4), LDHB (p = 1.0 × 10-3), and HINT1 (p = 3.8 × 10-3) pathways were significantly downregulated in the recurrent cohort. On functional validation via immunohistochemistry (IHC) staining, 46.9% (PFN1), 71.9% (RAD23B), 59.4% (LDHB), and 84.4% (HINT1) of cases were corroborated with mass spectrometry findings. Development of a multilateral molecular signature incorporating these targets may characterize high-risk disease, predict treatment response, and augment current management paradigms in head and neck cancer.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Enzimas Reparadoras do DNA , Proteínas de Ligação a DNA , Humanos , Proteínas do Tecido Nervoso , Neoplasias Orofaríngeas/patologia , Papillomaviridae/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Profilinas , Prognóstico , Proteômica , Carcinoma de Células Escamosas de Cabeça e Pescoço
8.
Plant Physiol ; 186(4): 2003-2020, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-33930167

RESUMO

The quality control system for messenger RNA (mRNA) is fundamental for cellular activities in eukaryotes. To elucidate the molecular mechanism of 3'-phosphoinositide-dependent protein kinase1 (PDK1), a master regulator that is essential throughout eukaryotic growth and development, we employed a forward genetic approach to screen for suppressors of the loss-of-function T-DNA insertion double mutant pdk1.1 pdk1.2 in Arabidopsis thaliana. Notably, the severe growth attenuation of pdk1.1 pdk1.2 was rescued by sop21 (suppressor of pdk1.1 pdk1.2), which harbors a loss-of-function mutation in PELOTA1 (PEL1). PEL1 is a homolog of mammalian PELOTA and yeast (Saccharomyces cerevisiae) DOM34p, which each form a heterodimeric complex with the GTPase HBS1 (HSP70 SUBFAMILY B SUPPRESSOR1, also called SUPERKILLER PROTEIN7, SKI7), a protein that is responsible for ribosomal rescue and thereby assures the quality and fidelity of mRNA molecules during translation. Genetic analysis further revealed that a dysfunctional PEL1-HBS1 complex failed to degrade the T-DNA-disrupted PDK1 transcripts, which were truncated but functional, and thus rescued the growth and developmental defects of pdk1.1 pdk1.2. Our studies demonstrated the functionality of a homologous PELOTA-HBS1 complex and identified its essential regulatory role in plants, providing insights into the mechanism of mRNA quality control.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo
9.
BMC Cancer ; 22(1): 1290, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494680

RESUMO

BACKGROUND: Metabolic reprogramming is a hallmark of cancer, alteration of nucleotide metabolism of hepatocellular carcinoma (HCC) is not well-understood. MYBL2 regulates cell cycle progression and hepatocarcinogenesis, its role in metabolic regulation remains elusive. PATIENTS AND METHODS: Copy number, mRNA and protein level of MYBL2 and IMPDH1 were analyzed in HCC, and correlated with patient survival. Chromatin Immunoprecipitation sequencing (Chip-seq) and Chromatin Immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) were used to explore the relationship between MYBL2 and IMPDH1. Metabolomics were used to analyze how MYBL2 affected purine metabolism. The regulating effect of MYBL2 in HCC was further validated in vivo using xenograft models. RESULTS: The Results showed that copy-number alterations of MYBL2 occur in about 10% of human HCC. Expression of MYBL2, IMPDH1, or combination of both were significantly upregulated and associated with poor prognosis in HCC. Correlation, ChIP-seq and ChIP-qPCR analysis revealed that MYBL2 activates transcription of IMPDH1, while knock-out of MYBL2 retarded IMPDH1 expression and inhibited proliferation of HCC cells. Metabolomic analysis post knocking-out of MYBL2 demonstrated that it was essential in de novo purine synthesis, especially guanine nucleotides. In vivo analysis using xenograft tumors also revealed MYBL2 regulated purine synthesis by regulating IMPDH1, and thus, influencing tumor progression. CONCLUSION: MYBL2 is a key regulator of purine synthesis and promotes HCC progression by transcriptionally activating IMPDH1, it could be a potential candidate for targeted therapy for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Progressão da Doença , Purinas , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Linhagem Celular Tumoral , IMP Desidrogenase/genética , IMP Desidrogenase/metabolismo , Transativadores/metabolismo , Proteínas de Ciclo Celular/metabolismo
10.
Nucleic Acids Res ; 48(20): 11434-11451, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33080033

RESUMO

Core regulatory circuitry (CRC)-dependent transcriptional network is critical for developmental tumors in children and adolescents carrying few gene mutations. However, whether and how CRC contributes to transcription regulation in Ewing sarcoma is unknown. Here, we identify and functionally validate a CRC 'trio' constituted by three transcription factors (TFs): KLF15, TCF4 and NKX2-2, in Ewing sarcoma cells. Epigenomic analyses demonstrate that EWS-FLI1, the primary fusion driver for this cancer, directly establishes super-enhancers of each of these three TFs to activate their transcription. In turn, KLF15, TCF4 and NKX2-2 co-bind to their own and each other's super-enhancers and promoters, forming an inter-connected auto-regulatory loop. Functionally, CRC factors contribute significantly to cell proliferation of Ewing sarcoma both in vitro and in vivo. Mechanistically, CRC factors exhibit prominent capacity of co-regulating the epigenome in cooperation with EWS-FLI1, occupying 77.2% of promoters and 55.6% of enhancers genome-wide. Downstream, CRC TFs coordinately regulate gene expression networks in Ewing sarcoma, controlling important signaling pathways for cancer, such as lipid metabolism pathway, PI3K/AKT and MAPK signaling pathways. Together, molecular characterization of the oncogenic CRC model advances our understanding of the biology of Ewing sarcoma. Moreover, CRC-downstream genes and signaling pathways may contain potential therapeutic targets for this malignancy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Proteínas de Fusão Oncogênica/metabolismo , Proteína Proto-Oncogênica c-fli-1/metabolismo , Proteína EWS de Ligação a RNA/metabolismo , Sarcoma de Ewing/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Metabolismo dos Lipídeos/genética , Camundongos Nus , Proteínas Nucleares , Proteínas de Fusão Oncogênica/fisiologia , Proteína Proto-Oncogênica c-fli-1/fisiologia , Proteína EWS de Ligação a RNA/fisiologia , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patologia , Transdução de Sinais , Fator de Transcrição 4/genética , Fator de Transcrição 4/metabolismo , Fatores de Transcrição , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
11.
Nucleic Acids Res ; 48(D1): D307-D313, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31598693

RESUMO

RNA binding proteins (RBPs) are a large protein family that plays important roles at almost all levels of gene regulation through interacting with RNAs, and contributes to numerous biological processes. However, the complete list of eukaryotic RBPs including human is still unavailable. Here, we systematically identified RBPs in 162 eukaryotic species based on both computational analysis of RNA binding domains (RBDs) and large-scale RNA binding proteomic data, and established a comprehensive eukaryotic RBP database, EuRBPDB (http://EuRBPDB.syshospital.org). We identified a total of 311 571 RBPs with RBDs (corresponding to 6368 ortholog groups) and 3,651 non-canonical RBPs without known RBDs. EuRBPDB provides detailed annotations for each RBP, including basic information and functional annotation. Moreover, we systematically investigated RBPs in the context of cancer biology based on published literatures, PPI-network and large-scale omics data. To facilitate the exploration of the clinical relevance of RBPs, we additionally designed a cancer web interface to systematically and interactively display the biological features of RBPs in various types of cancers. EuRBPDB has a user-friendly web interface with browse and search functions, as well as data downloading function. We expect that EuRBPDB will be a widely-used resource and platform for both the communities of RNA biology and cancer biology.


Assuntos
Neoplasias , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Bases de Dados de Proteínas , Eucariotos , Humanos , Internet , Mutação , Neoplasias/química , Motivos de Ligação ao RNA , Proteínas de Ligação a RNA/genética
12.
J Am Chem Soc ; 143(11): 4193-4204, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33352040

RESUMO

High-entropy oxides (HEOs) have attracted great interest in diverse fields because of their inherent opportunities to tailor and combine materials functionalities. The control of local order/disorder in the class is by extension a grand challenge toward realizing their vast potential. Here we report the first examples of pyrochlore HEOs with five M-site cations, for Nd2M2O7, in which the local structure has been investigated by neutron diffraction and pair distribution function (PDF) analysis. The average structure of the pyrochlores is found to be orthorhombic Imma, in agreement with radius-ratio rules governing the structural archetype. The computed PDFs from density functional theory relaxed special quasirandom structure models are compared with real space PDFs in this work to evaluate M-site order/disorder. Reverse Monte Carlo combined with ab initio molecular dynamics and Metropolis Monte Carlo simulations demonstrates that Nd2(Ta0.2Sc0.2Sn0.2Hf0.2Zr0.2)2O7 is synthesized with its M-site local to nanoscale order highly randomized/disordered, while Nd2(Ti0.2Nb0.2Sn0.2Hf0.2Zr0.2)2O7+x exhibits a strong distortion of the TiO6 octahedron and small degree of Ti chemical short-range order (SRO) on the subnanometer scale. Calculations suggest that this may be intrinsic, energetically favored SRO rather than due to sample processing. These results offer an important demonstration that the engineered variation of participating ions in HEOs, even among those with very similar radii, provides richly diverse opportunities to control local order/disorder motifs-and therefore materials properties for future designs. This work also hints at the exquisite level of detail that may be needed in computational and experimental data analysis to guide structure-property tuning in the emerging HEO materials class.

13.
Cancer ; 127(10): 1590-1597, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33595897

RESUMO

BACKGROUND: Modern disease staging systems have restructured human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) oropharyngeal carcinoma (OPC) into distinct pathologic nodal systems. Given that quantitative lymph node (LN) burden is the dominant prognostic factor in most head and neck cancers, we investigated whether HPV- and HPV+ OPC warrant divergent pathologic nodal classification. METHODS: Multivariable Cox regression models of OPC surgical patients identified via U.S. cancer registry data were constructed to determine associations between survival and nodal characteristics. Nonlinear associations between metastatic LN number and survival were modeled with restricted cubic splines. Recursive partitioning analysis (RPA) was used to derive unbiased nodal schema. RESULTS: Mortality risk escalated continuously with each successive positive LN in both OPC subtypes, with analogous slope. Survival hazard increased by 18.5% (hazard ratio [HR], 1.19 [95% CI, 1.16-1.21]; P < .001) and 19.1% (HR, 1.19 [95% CI, 1.17-1.21]; P < .001), with each added positive LN for HPV- and HPV+ OPC, respectively, up to identical change points of 5 positive LNs. Extranodal extension (ENE) was an independent predictor of HPV- OPC (HR, 1.55 [95% CI, 1.20-1.99]; P < .001) and HPV+ OPC (HR 1.73 [95% CI, 1.36-2.20]; P < .001) mortality. In RPA for both diseases, metastatic LN was the principal nodal covariate driving survival, with ENE as a secondary determinant. Given the similarities across analyses, we propose a concise, unifying HPV-/HPV+ OPC pathologic nodal classification schema: N1, 1-5 LN+/ENE-; N2, 1-5 LN+/ENE+; N3, >5 LN+. CONCLUSION: HPV- and HPV+ OPC exhibit parallel relationships between nodal characteristics and relative mortality. In both diseases, metastatic LN number represents the principal nodal covariate governing survival, with ENE being an influential secondary element. A consolidated OPC pathologic nodal staging system that is based on these covariates may best convey prognosis. LAY SUMMARY: The current nodal staging system for oropharyngeal carcinoma (OPC) has divided human papillomavirus (HPV)-negative (HPV-) and HPV-positive (HPV+) OPC into distinct systems that rely upon criteria that establish them as separate entities, a complexity that may undermine the core objective of staging schema to clearly communicate prognosis. Our large-scale analysis revealed that HPV- and HPV+ pathologic nodal staging systems in fact mirror each other. Multiple analyses produced conspicuously similar nodal staging systems, with metastatic lymph node number and extranodal extension delineating the highest risk groups that shape prognosis. We propose unifying HPV- and HPV+ nodal systems to best streamline prognostication and maximize staging accuracy.


Assuntos
Carcinoma , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Carcinoma/patologia , Carcinoma/virologia , Humanos , Estadiamento de Neoplasias , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/epidemiologia , Prognóstico
14.
Gastroenterology ; 159(4): 1311-1327.e19, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32619460

RESUMO

BACKGROUND & AIMS: We investigated the transcriptome of esophageal squamous cell carcinoma (ESCC) cells, activity of gene regulatory (enhancer and promoter regions), and the effects of blocking epigenetic regulatory proteins. METHODS: We performed chromatin immunoprecipitation sequencing with antibodies against H3K4me1, H3K4me3, and H3K27ac and an assay for transposase-accessible chromatin to map the enhancer regions and accessible chromatin in 8 ESCC cell lines. We used the CRC_Mapper algorithm to identify core regulatory circuitry transcription factors in ESCC cell lines, and determined genome occupancy profiles for 3 of these factors. In ESCC cell lines, expression of transcription factors was knocked down with small hairpin RNAs, promoter and enhancer regions were disrupted by CRISPR/Cas9 genome editing, or bromodomains and extraterminal (BET) family proteins and histone deacetylases (HDACs) were inhibited with ARV-771 and romidepsin, respectively. ESCC cell lines were then analyzed by whole-transcriptome sequencing, immunoprecipitation, immunoblots, immunohistochemistry, and viability assays. Interactions between distal enhancers and promoters were identified and verified with circular chromosome conformation capture sequencing. NOD-SCID mice were given injections of modified ESCC cells, some mice where given injections of HDAC or BET inhibitors, and growth of xenograft tumors was measured. RESULTS: We identified super-enhancer-regulated circuits and transcription factors TP63, SOX2, and KLF5 as core regulatory factors in ESCC cells. Super-enhancer regulation of ALDH3A1 mediated by core regulatory factors was required for ESCC viability. We observed direct interactions between the promoter region of TP63 and functional enhancers, mediated by the core regulatory circuitry transcription factors. Deletion of enhancer regions from ESCC cells decreased expression of the core regulatory circuitry transcription factors and reduced cell viability; these same results were observed with knockdown of each core regulatory circuitry transcription factor. Incubation of ESCC cells with BET and HDAC disrupted the core regulatory circuitry program and the epigenetic modifications observed in these cells; mice given injections of HDAC or BET inhibitors developed smaller xenograft tumors from the ESCC cell lines. Xenograft tumors grew more slowly in mice given the combination of ARV-771 and romidepsin than mice given either agent alone. CONCLUSIONS: In epigenetic and transcriptional analyses of ESCC cell lines, we found the transcription factors TP63, SOX2, and KLF5 to be part of a core regulatory network that determines chromatin accessibility, epigenetic modifications, and gene expression patterns in these cells. A combination of epigenetic inhibitors slowed growth of xenograft tumors derived from ESCC cells in mice.


Assuntos
Epigênese Genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição/genética , Transcrição Gênica , Proteínas Supressoras de Tumor/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Montagem e Desmontagem da Cromatina , Epigênese Genética/efeitos dos fármacos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcriptoma , Carga Tumoral , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Genome Res ; 28(11): 1747-1756, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30341162

RESUMO

Numerous large-scale genomic studies of matched tumor-normal samples have established the somatic landscapes of most cancer types. However, the downstream analysis of data from somatic mutations entails a number of computational and statistical approaches, requiring usage of independent software and numerous tools. Here, we describe an R Bioconductor package, Maftools, which offers a multitude of analysis and visualization modules that are commonly used in cancer genomic studies, including driver gene identification, pathway, signature, enrichment, and association analyses. Maftools only requires somatic variants in Mutation Annotation Format (MAF) and is independent of larger alignment files. With the implementation of well-established statistical and computational methods, Maftools facilitates data-driven research and comparative analysis to discover novel results from publicly available data sets. In the present study, using three of the well-annotated cohorts from The Cancer Genome Atlas (TCGA), we describe the application of Maftools to reproduce known results. More importantly, we show that Maftools can also be used to uncover novel findings through integrative analysis.


Assuntos
Evolução Clonal , Neoplasias/genética , Análise de Sequência de DNA/métodos , Software , Humanos , Taxa de Mutação
16.
Bioinformatics ; 36(5): 1649-1651, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31603498

RESUMO

SUMMARY: Cancer hallmarks rely on its specific transcriptional programs, which are dysregulated by multiple mechanisms, including genomic aberrations in the DNA regulatory regions. Genome-wide association studies have shown many variants are found within putative enhancer elements. To provide insights into the regulatory role of enhancer-associated non-coding variants in cancer epigenome, and to facilitate the identification of functional non-coding mutations, we present dbInDel, a database where we have comprehensively analyzed enhancer-associated insertion and deletion variants for both human and murine samples using ChIP-Seq data. Moreover, we provide the identification and visualization of upstream TF binding motifs in InDel-containing enhancers. Downstream target genes are also predicted and analyzed in the context of cancer biology. The dbInDel database promotes the investigation of functional contributions of non-coding variants in cancer epigenome. AVAILABILITY AND IMPLEMENTATION: The database, dbInDel, can be accessed from http://enhancer-indel.cam-su.org/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Elementos Facilitadores Genéticos , Estudo de Associação Genômica Ampla , Animais , Sequenciamento de Cromatina por Imunoprecipitação , Genômica , Humanos , Camundongos , Ligação Proteica
17.
Ann Surg Oncol ; 28(3): 1731-1739, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32808161

RESUMO

BACKGROUND: While numerous factors affect prognosis in papillary thyroid carcinoma (PTC), the comparative impact of histologic grade has not been well described. Moreover, indications for external beam radiation therapy (EBRT) remain imprecise. We evaluate clinicopathologic characteristics and outcomes for PTC stratified by grade. METHODS: We profiled histologic grade for PTC (well differentiated, moderately differentiated, poorly differentiated) via hospital (National Cancer Database) and population-based (Surveillance, Epidemiology, and End Results) registries. Cox regression was used to adjust for clinicopathologic covariates. Statistical interactions between subtypes and the effect of EBRT on survival were assessed. RESULTS: Collectively, worsening clinicopathologic factors (age, tumor size, extrathyroidal extension, nodal spread, M1 disease) and outcomes (disease-free survival, overall survival) correlated with less differentiated state, across all histologic grades (p < 0.001). Multivariable analysis showed escalating hazard with loss of differentiation relative to well-differentiated PTC (moderately differentiated hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.04-1.41, p = 0.02; poorly differentiated HR 2.62, 95% CI 2.23-3.08, p < 0.001). Correspondingly, greater survival benefit was associated with EBRT for poorly differentiated cases (HR 0.36, 95% CI 0.18-0.72, p = 0.004). This finding was upheld after landmark analysis to address potential immortal time bias (HR 0.37, 95% CI 0.17-0.80, p = 0.01). CONCLUSIONS: Worsening histologic grade in PTC is independently associated with parallel escalation in mortality risk, on a scale approximating or surpassing established thyroid cancer risk factors. On preliminary analysis, EBRT was associated with improved survival in the most aggressive or least differentiated subvariants. Further investigation is warranted to examine the efficacy of EBRT for select poorly differentiated thyroid carcinomas.


Assuntos
Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Intervalo Livre de Doença , Humanos , Prognóstico
18.
Nucleic Acids Res ; 47(3): 1255-1267, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30496486

RESUMO

As the second most common malignant bone tumor in children and adolescents, Ewing sarcoma is initiated and exacerbated by a chimeric oncoprotein, most commonly, EWS-FLI1. In this study, we apply epigenomic analysis to characterize the transcription dysregulation in this cancer, focusing on the investigation of super-enhancer and its associated transcriptional regulatory mechanisms. We demonstrate that super-enhancer-associated transcripts are significantly enriched in EWS-FLI1 target genes, contribute to the aberrant transcriptional network of the disease, and mediate the exceptional sensitivity of Ewing sarcoma to transcriptional inhibition. Through integrative analysis, we identify MEIS1 as a super-enhancer-driven oncogene, which co-operates with EWS-FLI1 in transcriptional regulation, and plays a key pro-survival role in Ewing sarcoma. Moreover, APCDD1, another super-enhancer-associated gene, acting as a downstream target of both MEIS1 and EWS-FLI1, is also characterized as a novel tumor-promoting factor in this malignancy. These data delineate super-enhancer-mediated transcriptional deregulation in Ewing sarcoma, and uncover numerous candidate oncogenes which can be exploited for further understanding of the molecular pathogenesis for this disease.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Proteína Meis1/genética , Sarcoma de Ewing/genética , Transcrição Gênica , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Elementos Facilitadores Genéticos , Regulação Neoplásica da Expressão Gênica , Humanos , Motivos de Nucleotídeos/genética , Proteínas de Fusão Oncogênica/genética , Proteína Proto-Oncogênica c-fli-1/genética , Proteína EWS de Ligação a RNA/genética , Sarcoma de Ewing/patologia , Transdução de Sinais/genética
19.
Nucleic Acids Res ; 47(W1): W248-W255, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31028388

RESUMO

Super-enhancers (SEs) have prominent roles in biological and pathological processes through their unique transcriptional regulatory capability. To date, several SE databases have been developed by us and others. However, these existing databases do not provide downstream or upstream regulatory analyses of SEs. Pathways, transcription factors (TFs), SEs, and SE-associated genes form complex regulatory networks. Therefore, we designed a novel web server, SEanalysis, which provides comprehensive SE-associated regulatory network analyses. SEanalysis characterizes SE-associated genes, TFs binding to target SEs, and their upstream pathways. The current version of SEanalysis contains more than 330 000 SEs from more than 540 types of cells/tissues, 5042 TF ChIP-seq data generated from these cells/tissues, DNA-binding sequence motifs for ∼700 human TFs and 2880 pathways from 10 databases. SEanalysis supports searching by either SEs, samples, TFs, pathways or genes. The complex regulatory networks formed by these factors can be interactively visualized. In addition, we developed a customizable genome browser containing >6000 customizable tracks for visualization. The server is freely available at http://licpathway.net/SEanalysis.


Assuntos
Bases de Dados Genéticas , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Software , Sítios de Ligação/genética , Humanos , Internet , Fatores de Transcrição/genética
20.
Hu Li Za Zhi ; 68(2): 18-24, 2021 Apr.
Artigo em Zh | MEDLINE | ID: mdl-33792015

RESUMO

Data collected over the past four decades show the life expectancy of indigenous Taiwanese to be 8 to 10 years lower than the general, predominantly Han Chinese, population. This suggests the persistence of inequities in the public health system in Taiwan. Several facets of this issue, including lack of consideration of the characteristics and lifestyle of ethnic populations in health policy planning and implementation work and the continued location-based focus of medical care resource distribution policies, are being actively discussed. However, investigations of factors related to the relatively poor health status of indigenous Taiwanese have not considered the traumatic and lingering effects of colonisation. This article briefly introduces the health status of indigenous Taiwanese and the indigenous nursing workforce and then presents a review of the literature on factors related to the under-representation of indigenous Taiwanese in nursing programs and the nursing workforce. Indigenous Taiwanese were found to be absent from public-health policymaking. Moreover, indigenous-related traditional knowledge and values are not being effectively transmitted to younger generations. A diverse nursing workforce should reflect and respond to not only indigenous peoples but also the general population in Taiwan.


Assuntos
Serviços de Saúde do Indígena , Povos Indígenas , Enfermeiras e Enfermeiros , Serviços de Saúde do Indígena/organização & administração , Humanos , Povos Indígenas/estatística & dados numéricos , Enfermeiras e Enfermeiros/estatística & dados numéricos , Taiwan
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa