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1.
Emerg Microbes Infect ; 12(2): 2256416, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37672505

RESUMO

The emergence of novel betacoronaviruses has posed significant financial and human health burdens, necessitating the development of appropriate tools to combat future outbreaks. In this study, we have characterized a human cell line, IGROV-1, as a robust tool to detect, propagate, and titrate betacoronaviruses SARS-CoV-2 and HCoV-OC43. IGROV-1 cells can be used for serological assays, antiviral drug testing, and isolating SARS-CoV-2 variants from patient samples. Using time-course transcriptomics, we confirmed that IGROV-1 cells exhibit a robust innate immune response upon SARS-CoV-2 infection, recapitulating the response previously observed in primary human nasal epithelial cells. We performed genome-wide CRISPR knockout genetic screens in IGROV-1 cells and identified Aryl hydrocarbon receptor (AHR) as a critical host dependency factor for both SARS-CoV-2 and HCoV-OC43. Using DiMNF, a small molecule inhibitor of AHR, we observed that the drug selectively inhibits HCoV-OC43 infection but not SARS-CoV-2. Transcriptomic analysis in primary normal human bronchial epithelial cells revealed that DiMNF blocks HCoV-OC43 infection via basal activation of innate immune responses. Our findings highlight the potential of IGROV-1 cells as a valuable diagnostic and research tool to combat betacoronavirus diseases.


Assuntos
COVID-19 , Coronavirus Humano OC43 , Humanos , Coronavirus Humano OC43/genética , SARS-CoV-2 , Receptores de Hidrocarboneto Arílico/genética , Linhagem Celular
2.
PLoS Pathog ; 18(8): e1010763, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35939522

RESUMO

Transmembrane Protein 41B (TMEM41B) and Vacuole Membrane Protein 1 (VMP1) are two ER-associated lipid scramblases that play a role in autophagosome formation and cellular lipid metabolism. TMEM41B is also a recently validated host factor required by flaviviruses and coronaviruses. However, the exact underlying mechanism of TMEM41B in promoting viral infections remains an open question. Here, we validated that both TMEM41B and VMP1 are essential host dependency factors for all four serotypes of dengue virus (DENV) and human coronavirus OC43 (HCoV-OC43), but not chikungunya virus (CHIKV). While HCoV-OC43 failed to replicate entirely in both TMEM41B- and VMP1-deficient cells, we detected diminished levels of DENV infections in these cell lines, which were accompanied by upregulation of the innate immune dsRNA sensors, RIG-I and MDA5. Nonetheless, this upregulation did not correspondingly induce the downstream effector TBK1 activation and Interferon-beta expression. Despite low levels of DENV replication, classical DENV replication organelles were undetectable in the infected TMEM41B-deficient cells, suggesting that the upregulation of the dsRNA sensors is likely a consequence of aberrant viral replication rather than a causal factor for reduced DENV infection. Intriguingly, we uncovered that the inhibitory effect of TMEM41B deficiency on DENV replication, but not HCoV-OC43, can be partially reversed using exogenous fatty acid supplements. In contrast, VMP1 deficiency cannot be rescued using the metabolite treatment. In line with the observed phenotypes, we found that both TMEM41B- and VMP1-deficient cells harbor higher levels of compromised mitochondria, especially in VMP1 deficiency which results in severe dysregulations of mitochondrial beta-oxidation. Using a metabolomic profiling approach, we revealed distinctive global dysregulations of the cellular metabolome, particularly lipidome, in TMEM41B- and VMP1-deficient cells. Our findings highlight a central role for TMEM41B and VMP1 in modulating multiple cellular pathways, including lipid mobilization, mitochondrial beta-oxidation, and global metabolic regulations, to facilitate the replication of flaviviruses and coronaviruses.


Assuntos
Infecções por Coronavirus , Coronavirus , Dengue , Metabolismo Energético , Humanos , Lipídeos , Proteínas de Membrana/genética , Replicação Viral
3.
Medicine (Baltimore) ; 100(46): e27595, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34797281

RESUMO

ABSTRACT: The main purpose of this study was to build a prediction model for patients with contralateral breast cancer (CBC) using competing risks methodology. The aim is to help clinicians predict the probability of CBC in breast cancer (BC) survivors.We reviewed data from the Surveillance, Epidemiology, and End Results database of 434,065 patients with BC. Eligible patients were used to quantify the association between the development of CBC and multiple characteristics of BC patients using competing risk models. A nomogram was also created to facilitate clinical visualization and analysis. Finally, the stability of the model was verified using concordance index and calibration plots, and decision curve analysis was used to evaluate the clinical utility of the model by calculating the net benefit.Four hundred thirty-four thousand sixty-five patients were identified, of whom 6944 (1.6%) developed CBC in the 10 years follow-up. The 10-year cumulative risk of developing CBC was 2.69%. According to a multivariate competing risk model, older patients with invasive lobular carcinoma who had undergone unilateral BC surgery, and whose tumor was better differentiated, of smaller size and ER-negative/PR-positive, had a higher risk of CBC. The calibration plots illustrated an acceptable correlation between the prediction by nomogram and actual observation, as the calibration curve was closed to the 45° diagonal line. The concordance index for the nomogram was 0.65, which indicated it was well calibrated for individual risk of CBC. Decision curve analysis produced a wide range of risk thresholds under which the model we built would yield a net benefit.BC survivors remain at high risk of developing CBC. Patients with CBC have a worse clinical prognosis compared to those with unilateral BC. We built a predictive model for the risk of developing CBC based on a large data cohort to help clinicians identify patients at high risk, which can then help them plan individualized surveillance and treatment.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Sobreviventes de Câncer , Nomogramas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Regras de Decisão Clínica , Feminino , Humanos , Incidência , Modelos Estatísticos , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Programa de SEER , Adulto Jovem
4.
Mol Carcinog ; 59(8): 967-979, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32424979

RESUMO

Drug resistance is the leading cause for rapid progression and relapse in small-cell lung cancer (SCLC) patients. Thus overcoming drug resistance still remains to be urgently resolved during SCLC treatment. Here, we found p62/SQSTM1 was enriched in SCLC spheroids, a subpopulation possessing cancer stem-like properties, which is responsible for cancer relapse and metastasis. Subsequent functional assays in vitro showed that short hairpin RNA (shRNA)-mediated p62 knockdown increased sensitivity of SCLC cell lines to cisplatin (DDP), whereas lentivirus-mediated p62 ectopic overexpression diminished DDP-induced cytotoxicity in both NCI-H446 and NCI-H1688 cell lines. Moreover, ectopic p62 overexpression promoted DDP resistance of NCI-H446 cells-derived tumor xenografts in immunodeficient mice in vivo, as indicated by accelerated tumor growth rate and reduced fluorescent activity of cleaved caspase-3. Gene expression profiling analysis revealed that p62 was positively correlated with neuronal precursor cell-expressed, developmentally downregulated gene 9 (NEDD9) expression level. Consistently, NEDD9 messenger RNA (mRNA) level was decreased upon p62 suppression by small interfering RNA (siRNA) and increased with p62 transient overexpression in SCLC cell lines, suggesting that p62 positively regulated NEDD9 mRNA. Depletion of NEDD9 by siRNA, to a large extent, reversed p62-overexpressed SCLC cells to DDP-induced cytotoxicity, implying NEDD9 might act as a downstream target which was in charge of p62-mediated DDP resistance. Taken together, our findings uncovered a previously unknown role of p62 in the regulation of SCLC drug resistance, assigning p62 as an attractive target for SCLC treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteína Sequestossoma-1/antagonistas & inibidores , Carcinoma de Pequenas Células do Pulmão/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , RNA Interferente Pequeno/genética , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Neurochem Res ; 41(8): 1845-56, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27097548

RESUMO

Multiple sclerosis (MS) is a multifactorial demyelinating disease characterized by neurodegenerative events and autoimmune response against myelin component. Citrullination or deimination, a post-translational modification of protein-bound arginine into citrulline, catalyzed by Ca(2+) dependent peptidylarginine deiminase enzyme (PAD), plays an essential role in physiological processes include gene expression regulation, apoptosis and the plasticity of the central nervous system, while aberrant citrullination can generate new epitopes, thus involving in the initiation and/or progression of autoimmune disorder like MS. Myelin basic protein (MBP) is the major myelin protein and is generally considered to maintain the stability of the myelin sheath. This review describes the MBP citrullination and its consequence, as well as offering further support for the "inside-out" hypothesis that MS is primarily a neurodegenerative disease with secondary inflammatory demyelination. In addition, it discusses the role of MBP citrullination in the immune inflammation and explores the potential of inhibition of PAD enzymes as a therapeutic strategy for the disease.


Assuntos
Citrulina/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Hidrolases/metabolismo , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Proteína Básica da Mielina/metabolismo , Animais , Sistemas de Liberação de Medicamentos/tendências , Humanos , Hidrolases/antagonistas & inibidores , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/metabolismo , Desiminases de Arginina em Proteínas
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