Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
1.
Int J Mol Sci ; 21(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150830

RESUMO

Colorectal cancer (CRC) is a highly prevailing cancer and the fourth leading cause of cancer mortality worldwide. Aberrant expression of antiapoptotic BCL-2 family proteins is closely linked to neoplastic progression and chemoresistance. Obatoclax is a clinically developed drug, which binds antiapoptotic BCL-2, BCL-xL, and MCL-1 for inhibition to elicit apoptosis. Survivin is an antiapoptotic protein, whose upregulation correlates with pathogenesis, therapeutic resistance, and poor prognosis in CRC. Herein, we provide the first evidence delineating the functional linkage between Obatoclax and survivin in the context of human CRC cells. In detail, Obatoclax was found to markedly downregulate survivin. This downregulation was mainly achieved via transcriptional repression, as Obatoclax lowered the levels of both survivin mRNA and promoter activity, while blocking proteasomal degradation failed to prevent survivin from downregulation by Obatoclax. Notably, ectopic survivin expression curtailed Obatoclax-induced apoptosis and cytotoxicity, confirming an essential role of survivin downregulation in Obatoclax-elicited anti-CRC effect. Moreover, Obatoclax was found to repress hyperactive WNT/ß-catenin signaling activity commonly present in human CRC cells, and, markedly, ectopic expression of dominant-active ß-catenin mutant rescued the levels of survivin along with elevated cell viability. We further revealed that, depending on the cell context, Obatoclax suppresses WNT/ß-catenin signaling in HCT 116 cells likely via inducing ß-catenin destabilization, or by downregulating LEF1 in DLD-1 cells. Collectively, we for the first time define survivin downregulation as a novel, pro-apoptotic mechanism of Obatoclax as a consequence of Obatocalx acting as an antagonist to WNT/ß-catenin signaling.


Assuntos
Apoptose , Neoplasias Colorretais/patologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirróis/farmacologia , Survivina/antagonistas & inibidores , Proteínas Wnt/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Biomarcadores Tumorais , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Indóis , Células Tumorais Cultivadas
2.
Mol Psychiatry ; 23(9): 1911-1919, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-28972577

RESUMO

Cigarette smoking is a leading cause of preventable mortality worldwide. Nicotine dependence, which reduces the likelihood of quitting smoking, is a heritable trait with firmly established associations with sequence variants in nicotine acetylcholine receptor genes and at other loci. To search for additional loci, we conducted a genome-wide association study (GWAS) meta-analysis of nicotine dependence, totaling 38,602 smokers (28,677 Europeans/European Americans and 9925 African Americans) across 15 studies. In this largest-ever GWAS meta-analysis for nicotine dependence and the largest-ever cross-ancestry GWAS meta-analysis for any smoking phenotype, we reconfirmed the well-known CHRNA5-CHRNA3-CHRNB4 genes and further yielded a novel association in the DNA methyltransferase gene DNMT3B. The intronic DNMT3B rs910083-C allele (frequency=44-77%) was associated with increased risk of nicotine dependence at P=3.7 × 10-8 (odds ratio (OR)=1.06 and 95% confidence interval (CI)=1.04-1.07 for severe vs mild dependence). The association was independently confirmed in the UK Biobank (N=48,931) using heavy vs never smoking as a proxy phenotype (P=3.6 × 10-4, OR=1.05, and 95% CI=1.02-1.08). Rs910083-C is also associated with increased risk of squamous cell lung carcinoma in the International Lung Cancer Consortium (N=60,586, meta-analysis P=0.0095, OR=1.05, and 95% CI=1.01-1.09). Moreover, rs910083-C was implicated as a cis-methylation quantitative trait locus (QTL) variant associated with higher DNMT3B methylation in fetal brain (N=166, P=2.3 × 10-26) and a cis-expression QTL variant associated with higher DNMT3B expression in adult cerebellum from the Genotype-Tissue Expression project (N=103, P=3.0 × 10-6) and the independent Brain eQTL Almanac (N=134, P=0.028). This novel DNMT3B cis-acting QTL variant highlights the importance of genetically influenced regulation in brain on the risks of nicotine dependence, heavy smoking and consequent lung cancer.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Tabagismo/genética , Adulto , Negro ou Afro-Americano/genética , Idoso , Alelos , População Negra/genética , DNA (Citosina-5-)-Metiltransferases/fisiologia , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Fumar/genética , População Branca/genética , DNA Metiltransferase 3B
3.
Int J Mol Sci ; 20(13)2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31323961

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor with poor prognosis, largely due to resistance to current radiotherapy and Temozolomide chemotherapy. The constitutive activation of Signal Transducer and Activator of Transcription 3 (STAT3) is evidenced as a pivotal driver of GBM pathogenesis and therapy resistance, and hence, is a promising GBM drug target. 5-acetyloxy-6,7,8,4'-tetramethoxyflavone (5-AcTMF) is an acetylated derivative of Tangeretin which is known to exert anticancer effects on breast, colon, lung, and multiple myeloma; however, its effect on GBM remains elusive. Herein, we reported that 5-AcTMF suppressed the viability and clonogenicity along with inducing apoptosis in multiple human GBM cell lines. Mechanistic analyses further revealed that 5-AcTMF lowered the levels of Tyrosine 705-phosphorylated STAT3 (p-STAT3), a canonical marker of STAT3 activation, but also dampened p-STAT3 upregulation elicited by Interleukin-6. Notably, ectopic expression of dominant-active STAT3 impeded 5-AcTMF-induced suppression of viability and clonogenicity plus apoptosis induction in GBM cells, confirming the prerequisite of STAT3 blockage for the inhibitory action of 5-AcTMF on GBM cell survival and growth. Additionally, 5-AcTMF impaired the activation of STAT3 upstream kinase JAK2 but also downregulated antiapoptotic BCL-2 and BCL-xL in a STAT3-dependent manner. Moreover, the overexpression of either BCL-2 or BCL-xL abrogated 5-AcTMF-mediated viability reduction and apoptosis induction in GBM cells. Collectively, we, for the first time, revealed the anticancer effect of 5-AcTMF on GBM cells, which was executed via thwarting the JAK2-STAT3-BCL-2/BCL-xL signaling axis. Our findings further implicate the therapeutic potential of 5-AcTMF for GBM treatment.


Assuntos
Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Flavonas/química , Flavonas/farmacologia , Glioblastoma/metabolismo , Fases de Leitura Aberta/genética , Fator de Transcrição STAT3/metabolismo , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Interleucina-6/metabolismo , Fator de Transcrição STAT3/genética , Proteína bcl-X/metabolismo
4.
Antimicrob Agents Chemother ; 60(11): 6518-6531, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27550363

RESUMO

Despite current prophylactic strategies, sexually transmitted infections (STIs) remain significant contributors to global health challenges, spurring the development of new multipurpose delivery technologies to protect individuals from and treat virus infections. However, there are few methods currently available to prevent and no method to date that cures human immunodeficiency virus (HIV) infection or combinations of STIs. While current oral and topical preexposure prophylaxes have protected against HIV infection, they have primarily relied on antiretrovirals (ARVs) to inhibit infection. Yet continued challenges with ARVs include user adherence to daily treatment regimens and the potential toxicity and antiviral resistance associated with chronic use. The integration of new biological agents may avert some of these adverse effects while also providing new mechanisms to prevent infection. Of the biologic-based antivirals, griffithsin (GRFT) has demonstrated potent inhibition of HIV-1 (and a multitude of other viruses) by adhering to and inactivating HIV-1 immediately upon contact. In parallel with the development of GRFT, electrospun fibers (EFs) have emerged as a promising platform for the delivery of agents active against HIV infection. In the study described here, our goal was to extend the mechanistic diversity of active agents and electrospun fibers by incorporating the biologic GRFT on the EF surface rather than within the EFs to inactivate HIV prior to cellular entry. We fabricated and characterized GRFT-modified EFs (GRFT-EFs) with different surface modification densities of GRFT and demonstrated their safety and efficacy against HIV-1 infection in vitro We believe that EFs are a unique platform that may be enhanced by incorporation of additional antiviral agents to prevent STIs via multiple mechanisms.


Assuntos
Proteínas de Algas/farmacologia , Antivirais/farmacologia , Sistemas de Liberação de Medicamentos/métodos , HIV-1/efeitos dos fármacos , Ácido Láctico/química , Lectinas de Plantas/farmacologia , Ácido Poliglicólico/química , Ligação Viral/efeitos dos fármacos , Proteínas de Algas/química , Antivirais/química , Linhagem Celular Transformada , Colo do Útero/citologia , Técnicas Eletroquímicas , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Feminino , Expressão Gênica , Genes Reporter , Células HeLa , Humanos , Luciferases/genética , Luciferases/metabolismo , Microscopia Eletrônica de Varredura , Lectinas de Plantas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Vagina/citologia , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
5.
Int J Mol Sci ; 18(1)2016 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-28035994

RESUMO

Colorectal cancer is the third most common cancer worldwide. Aberrant overexpression of antiapoptotic BCL-2 (B-cell lymphoma 2) family proteins is closely linked to tumorigenesis and poor prognosis in colorectal cancer. Obatoclax is an inhibitor targeting all antiapoptotic BCL-2 proteins. A previous study has described the antiproliferative action of obatoclax in one human colorectal cancer cell line without elucidating the underlying mechanisms. We herein reported that, in a panel of human colorectal cancer cell lines, obatoclax inhibits cell proliferation, suppresses clonogenicity, and induces G1-phase cell cycle arrest, along with cyclin D1 downregulation. Notably, ectopic cyclin D1 overexpression abrogated clonogenicity suppression but also G1-phase arrest elicited by obatoclax. Mechanistically, pre-treatment with the proteasome inhibitor MG-132 restored cyclin D1 levels in all obatoclax-treated cell lines. Cycloheximide chase analyses further revealed an evident reduction in the half-life of cyclin D1 protein by obatoclax, confirming that obatoclax downregulates cyclin D1 through induction of cyclin D1 proteasomal degradation. Lastly, threonine 286 phosphorylation of cyclin D1, which is essential for initiating cyclin D1 proteasomal degradation, was induced by obatoclax in one cell line but not others. Collectively, we reveal a novel anticancer mechanism of obatoclax by validating that obatoclax targets cyclin D1 for proteasomal degradation to downregulate cyclin D1 for inducing antiproliferation.


Assuntos
Carcinoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Ciclina D1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirróis/farmacologia , Regulação para Baixo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Indóis , Proteólise , Pirróis/toxicidade
6.
Clin Exp Dermatol ; 40(8): 827-2; quiz 832-3, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26456768

RESUMO

A 2006 survey of dermatologists showed that home phototherapy should be used with caution, and that general, nonevidence-based opinions were widespread about this form of therapy. This led to a randomized controlled trial to assess the safety and efficacy of home phototherapy vs. outpatient phototherapy by the same authors in 2009, which concluded that a lower burden of treatment and increased patient satisfaction were associated with home phototherapy. In the UK National Health Service, with a single exception, phototherapy is currently carried out exclusively in hospital. This contrasts with the Netherlands, where home phototherapy is now widely available. NHS dermatology services in the UK have yet to adopt home phototherapy as a treatment option, despite the strong evidence base and robust service models established elsewhere. In this review, we discuss evidence-based papers on home phototherapy, its advantages and disadvantages, economic effectiveness, and a suggested model for service sustainability.


Assuntos
Serviços de Assistência Domiciliar , Fototerapia/métodos , Psoríase/terapia , Análise Custo-Benefício , Humanos , Satisfação do Paciente , Reino Unido
8.
Br J Cancer ; 109(7): 1954-64, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24002594

RESUMO

BACKGROUND: The association between oral contraceptive (OC) use, hormone replacement therapy (HRT) and lung cancer risk in women is still debated. METHODS: We performed a pooled analysis of six case-control studies (1961 cases and 2609 controls) contributing to the International Lung Cancer Consortium. Potential associations were investigated with multivariable unconditional logistic regression and meta-analytic models. Multinomial logistic regressions were performed to investigate lung cancer risk across histologic types. RESULTS: A reduced lung cancer risk was found for OC (odds ratio (OR)=0.81; 95% confidence interval (CI): 0.68-0.97) and HRT ever users (OR=0.77; 95% CI: 0.66-0.90). Both oestrogen only and oestrogen+progestin HRT were associated with decreased risk (OR=0.76; 95% CI: 0.61-0.94, and OR=0.66; 95% CI: 0.49-0.88, respectively). No dose-response relationship was observed with years of OC/HRT use. The greatest risk reduction was seen for squamous cell carcinoma (OR=0.53; 95% CI: 0.37-0.76) in OC users and in both adenocarcinoma (OR=0.79; 95% CI: 0.66-0.95) and small cell carcinoma (OR=0.37; 95% CI: 0.19-0.71) in HRT users. No interaction with smoking status or BMI was observed. CONCLUSION: Our findings suggest that exogenous hormones can play a protective role in lung cancer aetiology. However, given inconsistencies with epidemiological evidence from cohort studies, further and larger investigations are needed for a more comprehensive view of lung cancer development in women.


Assuntos
Anticoncepcionais Orais/efeitos adversos , Terapia de Reposição Hormonal/efeitos adversos , Neoplasias Pulmonares/epidemiologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/etiologia , Idoso , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Estrogênios/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/etiologia , Pessoa de Meia-Idade , Progestinas/farmacologia , Risco , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Carcinoma de Pequenas Células do Pulmão/etiologia
9.
BMC Genom Data ; 24(1): 26, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37131148

RESUMO

HostSeq was launched in April 2020 as a national initiative to integrate whole genome sequencing data from 10,000 Canadians infected with SARS-CoV-2 with clinical information related to their disease experience. The mandate of HostSeq is to support the Canadian and international research communities in their efforts to understand the risk factors for disease and associated health outcomes and support the development of interventions such as vaccines and therapeutics. HostSeq is a collaboration among 13 independent epidemiological studies of SARS-CoV-2 across five provinces in Canada. Aggregated data collected by HostSeq are made available to the public through two data portals: a phenotype portal showing summaries of major variables and their distributions, and a variant search portal enabling queries in a genomic region. Individual-level data is available to the global research community for health research through a Data Access Agreement and Data Access Compliance Office approval. Here we provide an overview of the collective project design along with summary level information for HostSeq. We highlight several statistical considerations for researchers using the HostSeq platform regarding data aggregation, sampling mechanism, covariate adjustment, and X chromosome analysis. In addition to serving as a rich data source, the diversity of study designs, sample sizes, and research objectives among the participating studies provides unique opportunities for the research community.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Canadá/epidemiologia , Genômica , Sequenciamento Completo do Genoma
10.
mBio ; 13(3): e0081522, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35604092

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes a number of strategies to modulate viral and host mRNA translation. Here, we used ribosome profiling in SARS-CoV-2-infected model cell lines and primary airway cells grown at an air-liquid interface to gain a deeper understanding of the translationally regulated events in response to virus replication. We found that SARS-CoV-2 mRNAs dominate the cellular mRNA pool but are not more efficiently translated than cellular mRNAs. SARS-CoV-2 utilized a highly efficient ribosomal frameshifting strategy despite notable accumulation of ribosomes within the slippery sequence on the frameshifting element. In a highly permissive cell line model, although SARS-CoV-2 infection induced the transcriptional upregulation of numerous chemokine, cytokine, and interferon-stimulated genes, many of these mRNAs were not translated efficiently. The impact of SARS-CoV-2 on host mRNA translation was more subtle in primary cells, with marked transcriptional and translational upregulation of inflammatory and innate immune responses and downregulation of processes involved in ciliated cell function. Together, these data reveal the key role of mRNA translation in SARS-CoV-2 replication and highlight unique mechanisms for therapeutic development. IMPORTANCE SARS-CoV-2 utilizes a number of strategies to modulate host responses to ensure efficient propagation. Here, we used ribosome profiling in SARS-CoV-2-infected cells to gain a deeper understanding of the translationally regulated events in infected cells. We found that although viral mRNAs are abundantly expressed, they are not more efficiently translated than cellular mRNAs. SARS-CoV-2 utilized a highly efficient ribosomal frameshifting strategy and alternative translation initiation sites that help increase the coding potential of its RNAs. In permissive cells, SARS-CoV-2 infection induced the translational repression of numerous innate immune mediators. Though the impact of SARS-CoV-2 on host mRNA translation was more subtle in primary airway cell cultures, we noted marked transcriptional and translational upregulation of inflammatory and innate immune responses and downregulation of processes involved in ciliated cell function. Together, these data provide new insight into how SARS-CoV-2 modulates innate host responses and highlight unique mechanisms for therapeutic intervention.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/genética , Humanos , Imunidade Inata , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/metabolismo , SARS-CoV-2/genética
11.
Cancer Causes Control ; 22(7): 1037-46, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21607590

RESUMO

BACKGROUND: Cancers of the upper aerodigestive tract (UADT; including oral cavity, pharynx, larynx and oesophagus) have high incidence rates all over the world, and they are especially frequent in some parts of Latin America. However, the data on the role of the major risk factors in these areas are still limited. METHODS: We have evaluated the role of alcohol and tobacco consumption, based on 2,252 upper aerodigestive squamous-cell carcinoma cases and 1,707 controls from seven centres in Brazil, Argentina, and Cuba. RESULTS: We show that alcohol drinkers have a risk of UADT cancers that is up to five times higher than that of never-drinkers. A very strong effect of aperitifs and spirits as compared to other alcohol types was observed, with the ORs reaching 12.76 (CI 5.37-30.32) for oesophagus. Tobacco smokers were up to six times more likely to develop aerodigestive cancers than never-smokers, with the ORs reaching 11.14 (7.72-16.08) among current smokers for hypopharynx and larynx cancer. There was a trend for a decrease in risk after quitting alcohol drinking or tobacco smoking for all sites. The interactive effect of alcohol and tobacco was more than multiplicative. In this study, 65% of all UADT cases were attributable to a combined effect of alcohol and tobacco use. CONCLUSIONS: In this largest study on UADT cancer in Latin America, we have shown for the first time that a prevailing majority of UADT cancer cases is due to a combined effect of alcohol and tobacco use and could be prevented by quitting the use of either of these two agents.


Assuntos
Carcinoma/etiologia , Etanol/efeitos adversos , Neoplasias de Cabeça e Pescoço/etiologia , Nicotiana/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Carcinoma/epidemiologia , Estudos de Casos e Controles , Feminino , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
12.
bioRxiv ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33173862

RESUMO

SARS-CoV-2 utilizes a number of strategies to modulate viral and host mRNA translation. Here, we used ribosome profiling in SARS-CoV-2 infected model cell lines and primary airway cells grown at the air-liquid interface to gain a deeper understanding of the translationally regulated events in response to virus replication. We find that SARS-CoV-2 mRNAs dominate the cellular mRNA pool but are not more efficiently translated than cellular mRNAs. SARS-CoV-2 utilized a highly efficient ribosomal frameshifting strategy in comparison to HIV-1, suggesting utilization of distinct structural elements. In the highly permissive cell models, although SARS-CoV-2 infection induced the transcriptional upregulation of numerous chemokines, cytokines and interferon stimulated genes, many of these mRNAs were not translated efficiently. Impact of SARS-CoV-2 on host mRNA translation was more subtle in primary cells, with marked transcriptional and translational upregulation of inflammatory and innate immune responses and downregulation of processes involved in ciliated cell function. Together, these data reveal the key role of mRNA translation in SARS-CoV-2 replication and highlight unique mechanisms for therapeutic development.

13.
Cell Rep ; 36(2): 109364, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34214467

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) variants govern transmissibility, responsiveness to vaccination, and disease severity. In a screen for new models of SARS-CoV-2 infection, we identify human H522 lung adenocarcinoma cells as naturally permissive to SARS-CoV-2 infection despite complete absence of angiotensin-converting enzyme 2 (ACE2) expression. Remarkably, H522 infection requires the E484D S variant; viruses expressing wild-type S are not infectious. Anti-S monoclonal antibodies differentially neutralize SARS-CoV-2 E484D S in H522 cells as compared to ACE2-expressing cells. Sera from vaccinated individuals block this alternative entry mechanism, whereas convalescent sera are less effective. Although the H522 receptor remains unknown, depletion of surface heparan sulfates block H522 infection. Temporally resolved transcriptomic and proteomic profiling reveal alterations in cell cycle and the antiviral host cell response, including MDA5-dependent activation of type I interferon signaling. These findings establish an alternative SARS-CoV-2 host cell receptor for the E484D SARS-CoV-2 variant, which may impact tropism of SARS-CoV-2 and consequently human disease pathogenesis.


Assuntos
COVID-19/imunologia , COVID-19/metabolismo , Receptores Virais , Glicoproteína da Espícula de Coronavírus/metabolismo , Substituição de Aminoácidos , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Ciclo Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Perfilação da Expressão Gênica , Heparitina Sulfato/metabolismo , Humanos , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Modelos Biológicos , Ligação Proteica , Domínios Proteicos , Proteômica , Receptores Virais/metabolismo , SARS-CoV-2 , Serina Endopeptidases/metabolismo , Transdução de Sinais , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Internalização do Vírus , Replicação Viral
14.
bioRxiv ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33688646

RESUMO

Established in vitro models for SARS-CoV-2 infection are limited and include cell lines of non-human origin and those engineered to overexpress ACE2, the cognate host cell receptor. We identified human H522 lung adenocarcinoma cells as naturally permissive to SARS-CoV-2 infection despite complete absence of ACE2. Infection of H522 cells required the SARS-CoV-2 spike protein, though in contrast to ACE2-dependent models, spike alone was not sufficient for H522 infection. Temporally resolved transcriptomic and proteomic profiling revealed alterations in cell cycle and the antiviral host cell response, including MDA5-dependent activation of type-I interferon signaling. Focused chemical screens point to important roles for clathrin-mediated endocytosis and endosomal cathepsins in SARS-CoV-2 infection of H522 cells. These findings imply the utilization of an alternative SARS-CoV-2 host cell receptor which may impact tropism of SARS-CoV-2 and consequently human disease pathogenesis.

15.
Cancer Causes Control ; 21(11): 1799-806, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20623173

RESUMO

Cancers of the upper aerodigestive tract (UADT: oral cavity, oropharynx, hypopharynx, larynx, esophagus) have high incidence rates all over the world and they are especially frequent in some parts of Latin America. In this study, we have evaluated the role of the consumption of maté, a hot herb-based beverage, based on 1168 UADT squamous-cell carcinoma cases and 1,026 frequency-matched controls enrolled from four centers in Brazil and Argentina. The effect of maté drinking on the risk of head-and-neck cancers was borderline significant. A significant effect was observed only for cancer of the esophagus (OR 3.81 (95% CI 1.75-8.30)). While duration of maté drinking was associated with the risk of all UADT cancers, the association with cumulative maté consumption was restricted to esophageal cancer (p-value of linear trend 0.006). The analyses of temperature at which maté was drunk were not conclusive. The increased risk associated with maté drinking was more evident in never-smokers and never-alcohol drinkers than in other individuals. Our study strengthens the evidence of an association between maté drinking and esophageal cancer; the hypothesis of an association with other UADT cancers remains to be clarified.


Assuntos
Bebidas/efeitos adversos , Ingestão de Líquidos , Neoplasias Esofágicas/complicações , Neoplasias de Cabeça e Pescoço/complicações , Ilex paraguariensis/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Argentina/epidemiologia , Brasil/epidemiologia , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Estudos de Casos e Controles , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto
17.
bioRxiv ; 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32607508

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the ongoing COVID-19 pandemic, has infected millions within just a few months and is continuing to spread around the globe causing immense respiratory disease and mortality. Assays to monitor SARS-CoV-2 growth depend on time-consuming and costly RNA extraction steps, hampering progress in basic research and drug development efforts. Here we developed a facile Q-RT-PCR assay that bypasses viral RNA extraction steps and can monitor SARS-CoV-2 replication kinetics from a small amount of cell culture supernatants. Using this assay, we screened the activities of a number of entry, SARS-CoV-2- and HIV-1-specific inhibitors in a proof of concept study. In line with previous studies which has shown that processing of the viral Spike protein by cellular proteases and endosomal fusion are required for entry, we found that E64D and apilimod potently decreased the amount of SARS-CoV-2 RNA in cell culture supernatants with minimal cytotoxicity. Surprisingly, we found that macropinocytosis inhibitor EIPA similarly decreased viral RNA in supernatants suggesting that entry may additionally be mediated by an alternative pathway. HIV-1-specific inhibitors nevirapine (an NNRTI), amprenavir (a protease inhibitor), and ALLINI-2 (an allosteric integrase inhibitor) modestly inhibited SARS-CoV-2 replication, albeit the IC 50 values were much higher than that required for HIV-1. Taken together, this facile assay will undoubtedly expedite basic SARS-CoV-2 research, be amenable to mid-throughput screens to identify chemical inhibitors of SARS-CoV-2, and be applicable to a broad number of RNA and DNA viruses.

18.
mSphere ; 5(5)2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878932

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions within just a few months, causing severe respiratory disease and mortality. Assays to monitor SARS-CoV-2 growth in vitro depend on time-consuming and costly RNA extraction steps, hampering progress in basic research and drug development efforts. Here, we developed a simplified quantitative real-time PCR assay that bypasses viral RNA extraction steps and can monitor SARS-CoV-2 growth from a small amount of cell culture supernatants. In addition, we show that this approach is easily adaptable to numerous other RNA and DNA viruses. Using this assay, we screened the activities of a number of compounds that were predicted to alter SARS-CoV-2 entry and replication as well as HIV-1-specific drugs in a proof-of-concept study. We found that E64D (inhibitor of endosomal proteases cathepsin B and L) and apilimod (endosomal trafficking inhibitor) potently decreased the amount of SARS-CoV-2 RNA in cell culture supernatants with minimal cytotoxicity. Surprisingly, we found that the macropinocytosis inhibitor ethylisopropylamiloride (EIPA) similarly decreased SARS-CoV-2 RNA levels in supernatants, suggesting that entry may additionally be mediated by an alternative pathway. HIV-1-specific inhibitors nevirapine (a nonnucleoside reverse transcriptase inhibitor [NNRTI]), amprenavir (a protease inhibitor), and allosteric integrase inhibitor 2 (ALLINI-2) modestly inhibited SARS-CoV-2 replication, albeit the 50% inhibitory concentration (IC50) values were much higher than that required for HIV-1. Taking the data together, this simplified assay will expedite basic SARS-CoV-2 research, be amenable to mid-throughput screening assays (i.e., drug, CRISPR, small interfering RNA [siRNA], etc.), and be applicable to a broad number of RNA and DNA viruses.IMPORTANCE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the coronavirus disease 2019 (COVID-19) pandemic, is continuing to cause immense respiratory disease and social and economic disruptions. Conventional assays that monitor SARS-CoV-2 growth in cell culture rely on costly and time-consuming RNA extraction procedures, hampering progress in basic SARS-CoV-2 research and development of effective therapeutics. Here, we developed a simple quantitative real-time PCR assay to monitor SARS-CoV-2 growth in cell culture supernatants that does not necessitate RNA extraction and that is as accurate and sensitive as existing methods. In a proof-of-concept screen, we found that E64D, apilimod, EIPA, and remdesivir can substantially impede SARS-Cov-2 replication, providing novel insight into viral entry and replication mechanisms. In addition, we show that this approach is easily adaptable to numerous other RNA and DNA viruses. This simplified assay will undoubtedly expedite basic SARS-CoV-2 and virology research and be amenable to use in drug screening platforms to identify therapeutics against SARS-CoV-2.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/crescimento & desenvolvimento , Técnicas de Cultura de Células/métodos , Infecções por Coronavirus/virologia , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Betacoronavirus/genética , Betacoronavirus/patogenicidade , COVID-19 , Pandemias , RNA Viral/análise , RNA Viral/isolamento & purificação , SARS-CoV-2 , Replicação Viral/efeitos dos fármacos
19.
J Dent Res ; 98(8): 879-887, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31282843

RESUMO

In epidemiologic studies, patients with head and neck squamous cell carcinoma (HNSCC) are classified mainly by the International Classification of Diseases (ICD) codes. However, some patients are of an unclear subsite, the "gray zone" cases, which could reflect ICD coding error, absence of primary subsite, or extensive primary tumors that cross over multiple subsites of the oral cavity and oropharynx. Patients with gray zone squamous cell carcinomas were compared with patients with oral cavity squamous cell carcinoma (OSCC) or oropharyngeal squamous cell carcinoma (OPSCC) and stratified by human papillomavirus (HPV) status that was determined by p16 immunostaining or HPV serology. Comparisons consisted of clinicodemographic features and prognostic outcomes presented by Kaplan-Meier curves and Cox proportional hazards regression models, reported as hazard ratios. There were 158 consecutive patients with gray zone HNSCC diagnosed at the Princess Margaret Cancer Center between 2006 and 2017: 66 had subsite coding discrepancies against the clinician's documentation ("discrepant" cases; e.g., the diagnosis by the clinician was OSCC, while the classification by ICD coding was OPSCC), while 92 were squamous cell carcinoma of unknown primary of the head and neck (SCCUPHN) after complete diagnostic workup. Comparators included 721 consecutive OSCC and 938 OPSCC adult cases. All HPV-positive cohorts (OPSCC, discrepant, and SCCUPHN) had similar clinicodemographic characteristics and better 3- and 5-y overall survival and disease-free survival than their HPV-negative counterparts. In contrast, HPV-negative discrepant cases had prognostic outcomes most similar to HPV-negative OPSCC cases, while HPV-negative SCCUPHN had survival outcomes most similar to those of patients with OSCC in this study. HPV-positive status can improve the classification of patients with unclear or discrepant oral/oropharyngeal subsite, an improvement over classification systems that are solely clinician defined or conducted through ICD coding. However, due to clinical practice, we could not make definitive reclassification for patients with HPV-negative gray zone HNSCC.


Assuntos
Carcinoma de Células Escamosas/classificação , Neoplasias de Cabeça e Pescoço/classificação , Neoplasias Orofaríngeas/classificação , Papillomaviridae , Infecções por Papillomavirus , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/virologia , Codificação Clínica , Feminino , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Classificação Internacional de Doenças , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/virologia , Adulto Jovem
20.
Carcinogenesis ; 29(8): 1567-71, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18566013

RESUMO

This study investigated associations between occupational pesticide exposure and renal cell carcinoma (RCC) risk. To follow-up on a previous report by Buzio et al., we also considered whether this association could be modified by glutathione S-transferase M1 and T1 (GSTM1 and GSTT1) genotypes. About 1097 RCC cases and 1476 controls from Central and Eastern Europe were interviewed to collect data on lifetime occupational histories. Occupational information for jobs held for at least 12 months duration was coded for pesticide exposures and assessed for frequency and intensity of exposure. GSTM1 and GSTT1 gene deletions were analyzed using TaqMan assays. A significant increase in RCC risk was observed among subjects ever exposed to pesticides [odds ratio (OR): 1.60; 95% confidence interval (CI): 1.00-2.55]. After stratification by genotypes, increased risk was observed among exposed subjects with at least one GSTM1 active allele (OR: 4.00; 95% CI: 1.55-10.33) but not among exposed subjects with two GSTM1 inactive alleles compared with unexposed subjects with two inactive alleles (P-interaction: 0.04). Risk was highest among exposed subjects with both GSTM1 and GSTT1 active genotypes (OR: 6.47; 95% CI: 1.82-23.00; P-interaction: 0.02) compared with unexposed subjects with at least one GSTM1 or T1 inactive genotype. In the largest RCC case-control study with genotype information conducted to date, we observed that risk associated with pesticide exposure was exclusive to individuals with active GSTM1/T1 genotypes. These findings further support the hypothesis that glutathione S-transferase polymorphisms can modify RCC risk associated with occupational pesticide exposure.


Assuntos
Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/genética , Glutationa Transferase/genética , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/genética , Praguicidas/toxicidade , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/epidemiologia , Estudos de Casos e Controles , Europa (Continente)/epidemiologia , Feminino , Humanos , Entrevistas como Assunto , Neoplasias Renais/enzimologia , Neoplasias Renais/epidemiologia , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA