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1.
PLoS Pathog ; 20(1): e1011943, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38215174

RESUMO

Deubiquitinases (DUBs) remove ubiquitin from substrates and play crucial roles in diverse biological processes. However, our understanding of deubiquitination in viral replication remains limited. Employing an oncogenic human herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) to probe the role of protein deubiquitination, we found that Ovarian tumor family deubiquitinase 4 (OTUD4) promotes KSHV reactivation. OTUD4 interacts with the replication and transcription activator (K-RTA), a key transcription factor that controls KSHV reactivation, and enhances K-RTA stability by promoting its deubiquitination. Notably, the DUB activity of OTUD4 is not required for K-RTA stabilization; instead, OTUD4 functions as an adaptor protein to recruit another DUB, USP7, to deubiquitinate K-RTA and facilitate KSHV lytic reactivation. Our study has revealed a novel mechanism whereby KSHV hijacks OTUD4-USP7 deubiquitinases to promote lytic reactivation, which could be potentially harnessed for the development of new antiviral therapies.


Assuntos
Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Sarcoma de Kaposi , Humanos , Proteínas Imediatamente Precoces/metabolismo , Peptidase 7 Específica de Ubiquitina/genética , Peptidase 7 Específica de Ubiquitina/metabolismo , Transativadores/genética , Herpesvirus Humano 8/genética , Replicação Viral , Regulação Viral da Expressão Gênica , Ativação Viral , Proteases Específicas de Ubiquitina/metabolismo
2.
PLoS Pathog ; 20(4): e1012141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38626263

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is a double-stranded DNA virus etiologically associated with multiple malignancies. Both latency and sporadic lytic reactivation contribute to KSHV-associated malignancies, however, the specific roles of many KSHV lytic gene products in KSHV replication remain elusive. In this study, we report that ablation of ORF55, a late gene encoding a tegument protein, does not impact KSHV lytic reactivation but significantly reduces the production of progeny virions. We found that cysteine 10 and 11 (C10 and C11) of pORF55 are palmitoylated, and the palmytoilation is essential for its Golgi localization and secondary envelope formation. Palmitoylation-defective pORF55 mutants are unstable and undergo proteasomal degradation. Notably, introduction of a putative Golgi localization sequence to these palmitoylation-defective pORF55 mutants restores Golgi localization and fully reinstates KSHV progeny virion production. Together, our study provides new insight into the critical role of pORF55 palmitoylation in KSHV progeny virion production and offers potential therapeutic targets for the treatment of related malignancies.


Assuntos
Complexo de Golgi , Herpesvirus Humano 8 , Lipoilação , Proteínas Virais , Vírion , Replicação Viral , Herpesvirus Humano 8/fisiologia , Herpesvirus Humano 8/metabolismo , Complexo de Golgi/metabolismo , Complexo de Golgi/virologia , Humanos , Vírion/metabolismo , Proteínas Virais/metabolismo , Proteínas Virais/genética , Replicação Viral/fisiologia , Células HEK293
3.
J Virol ; 97(9): e0088123, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37681959

RESUMO

Epstein-Barr virus (EBV)-encoded miRNAs within the BamHI-A rightward transcript (BART) region are abundantly expressed in EBV-associated gastric cancer (EBVaGC), suggesting that they play roles in tumorigenesis. However, how these viral miRNAs contribute to the development of EBVaGC remains largely obscure. In this study, we found that EBV-encoded miR-BART11-3p targets 3' -UTR of dual-specificity phosphatase 6 (DUSP6) mRNA to upregulate ERK phosphorylation and downregulate JNK and p38 phosphorylation. By doing so, miR-BART11-3p promotes gastric cancer (GC) cell proliferation, migration, and invasion in vitro, and facilitates tumor growth in vivo. Restoration of DUSP6 expression reverses the tumor-promoting activity of miR-BART11-3p in AGS GC cells. Consistently, knockdown of DUSP6 ablates the antitumor effects of miR-BART11-3p inhibitors in EBV-positive GC cells. Furthermore, blocking ERK phosphorylation with trametinib inhibited the proliferation, migration, and invasion of miR-BART11-3p-expressing AGS cells. Administration of a miR-BART11-3p antagomir reduced the growth of EBV-positive xenograft tumors. Together, these findings reveal a novel mechanism by which EBV dysregulates MAPK pathways through an EBV-encoded microRNA to promote the development and progression of EBVaGC, which may be harnessed to develop new therapeutics to treat EBVaGC. IMPORTANCE The Epstein-Barr virus (EBV) is the first human tumor virus found to encode miRNAs, which within the BART region have been detected abundantly in EBV-associated gastric cancer (EBVaGC) and play various roles in promoting tumorigenesis. In our study, we observed that EBV-miR-BART11-3p promotes cell proliferation and induces migration and invasion in GC. Interestingly, we showed that miR-BART11-3p upregulates p-ERK and downregulates p-JNK and p-p38 by directly targeting 3'-UTR of dual-specificity phosphatase 6 (DUSP6). Restoration of DUSP6 rescues the effects generated by miR-BART11-3p in GC cells, and blocking ERK phosphorylation with Trametinib augments JNK and p38 phosphorylation and inhibits the effects of miR-BART11-3p-expressing AGS cells, suggesting that miR-BART11-3p promotes cell proliferation, migration, and invasion by modulating DUSP6-MAPK axis in EBVaGC. The findings presented in this study provide new mechanisms into the tumorigenesis in EBVaGC and new avenues for the development of therapeutic strategies to combat EBVaGC targeting miR-BART11-3p or phospho-ERK.

4.
J Med Virol ; 96(6): e29769, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38932482

RESUMO

Integration of the human papillomavirus (HPV) genome into the cellular genome is a key event that leads to constitutive expression of viral oncoprotein E6/E7 and drives the progression of cervical cancer. However, HPV integration patterns differ on a case-by-case basis among related malignancies. Next-generation sequencing technologies still face challenges for interrogating HPV integration sites. In this study, utilizing Nanopore long-read sequencing, we identified 452 and 108 potential integration sites from the cervical cancer cell lines (CaSki and HeLa) and five tissue samples, respectively. Based on long Nanopore chimeric reads, we were able to analyze the methylation status of the HPV long control region (LCR), which controls oncogene E6/E7 expression, and to identify transcriptionally-active integrants among the numerous integrants. As a proof of concept, we identified an active HPV integrant in between RUNX2 and CLIC5 on chromosome 6 in the CaSki cell line, which was supported by ATAC-seq, H3K27Ac ChIP-seq, and RNA-seq analysis. Knockout of the active HPV integrant, by the CRISPR/Cas9 system, dramatically crippled cell proliferation and induced cell senescence. In conclusion, identifying transcriptionally-active HPV integrants with Nanopore sequencing can provide viable targets for gene therapy against HPV-associated cancers.


Assuntos
Terapia Genética , Sequenciamento por Nanoporos , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Integração Viral , Humanos , Neoplasias do Colo do Útero/virologia , Feminino , Sequenciamento por Nanoporos/métodos , Integração Viral/genética , Terapia Genética/métodos , Infecções por Papillomavirus/virologia , Linhagem Celular Tumoral , Células HeLa , Proteínas Oncogênicas Virais/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Papillomaviridae/genética , Papillomavirus Humano
5.
J Med Virol ; 95(1): e28387, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478267

RESUMO

Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) is a distinct subtype of gastric cancer (GC) distinguished by the presence of the EBV genome and limited viral gene expression within malignant epithelial cells. EBV infection is generally thought to be a relatively late event following atrophic gastritis in carcinogenesis, which implies the heterogeneity of EBVaGC. To facilitate the study of the role of EBV in EBVaGC, we established two EBV-positive GC cell lines (AGS-EBV and HGC27-EBV) with an epitheliotropic EBV strain M81 and characterized viral and cellular gene expression profiles in comparison to SNU719, a naturally derived EBV-positive GC cell line. Like SNU719, AGS-EBV and HGC27-EBV stably maintained their EBV genomes and expressed EBV-encoded small RNAs and nuclear antigen EBNA1. Comprehensive analysis of the expression of EBV-encoded miRNAs within the BamHI-A region rightward transcript region, and the transcripts of EBV latent and lytic genes in cell lines, as well as xenografts, reveals that AGS-EBV and HGC27-EBV cells undergo distinct viral expression profiles. A very small fraction of AGS-EBV and SNU719 cells can spontaneously produce infectious progeny virions, while HGC27-EBV does not. AGS-EBV (both M81 and Akata) cells largely mimic SNU719 cells in viral gene expression profiles, and altered cellular functions and pathways perturbed by EBV infection. Phylogenetic analysis of the EBV genome shows both M81 and Akata EBV strains are closely related to clinical EBVaGC isolates. Taken together, these two newly established EBV-positive GC cell lines can serve as models to further investigate the role of EBV in different contexts of gastric carcinogenesis and identify novel therapeutics against EBVaGC.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Carcinogênese , Linhagem Celular/metabolismo , Linhagem Celular/virologia , Herpesvirus Humano 4/genética , Filogenia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/virologia
6.
J Med Virol ; 93(3): 1370-1377, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33095513

RESUMO

Renin-angiotensin-aldosterone system (RAAS) inhibitors, including angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are one of the most prescribed antihypertensive medications. Previous studies showed RAAS inhibitors increase the expression of ACE2, a cellular receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which provokes a concern that the use of ACEI and ARB in hypertensive individuals might lead to increased mortality and severity of coronavirus disease 2019 (COVID-19). To further investigate the effects of ACEI/ARB on COVID-19 patients, we systematically reviewed relevant studies that met predetermined inclusion criteria in search of PubMed, Embase, Cochrane Library databases, medRxiv, and bioRxiv. The search strategy included clinical data published through October 12, 2020. Twenty-six studies involving 8104 hypertensive patients in ACEI/ARB-treated group and 8203 hypertensive patients in non-ACEI/ARB-treated group were analyzed. Random-effects meta-analysis showed ACEI/ARB treatment was significantly associated with a lower risk of mortality in hypertensive COVID-19 patients (odds ratio [OR] = 0.624, 95% confidence interval [CI] = 0.457-0.852, p = .003, I2 = 74.3%). Meta-regression analysis showed that age, gender, study site, Newcastle-Ottawa Scale scores, comorbidities of diabetes, coronary artery disease, chronic kidney disease, or cancer has no significant modulating effect of ACEI/ARB treatment on the mortality of hypertensive COVID-19 patients (all p > .1). In addition, the ACEI/ARB treatment was associated with a lower risk of ventilatory support (OR = 0.682, 95% CI = 0.475-1.978, p = .037, I2 = 0.0%). In conclusion, these results suggest that ACEI/ARB medications should not be discontinued for hypertensive patients in the context of COVID-19 pandemic.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , COVID-19/complicações , COVID-19/mortalidade , Hipertensão/tratamento farmacológico , Comorbidade , Feminino , Humanos , Hipertensão/complicações , Masculino , Prognóstico , Fatores de Risco
7.
BMC Psychiatry ; 21(1): 19, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33419411

RESUMO

BACKGROUND: The 2019 coronavirus disease (COVID-19) has disrupted millions of lives and commerce. We investigated psychological reactions and insomnia during the COVID-19 outbreak in adults with mental health disorders (MDs). METHODS: A self-reported psychological and sleep online survey was conducted in China between February 5th to 19th, 2020. A total of 244 adults with MDs and 1116 controls matched for age, gender and sites were included. Worsened symptoms of anxiety, depressive and insomnia were defined when severity levels shifted to a more severe category compared to pre-COVID-19. RESULTS: During the COVID-19 outbreak, we found significantly increased prevalence of anxiety (MDs: 54.9% vs. 49.6%, controls: 25.5% vs. 14.3%), depression (MDs: 63.9% vs. 61.5%, controls: 29.9% vs. 21.2%) and insomnia (MDs: 66.0% vs. 57.8%, controls: 31.5% vs. 24.8%) compared to pre-COVID-19 period (all P-value < 0.001). Furthermore, adults with MDs had higher odds for developing COVID-19-related stress (OR = 3.41, 95% CI 2.49 ~ 4.67), worsened anxiety (OR = 1.95, 95% CI 1.38 ~ 2.76), depression (OR = 2.04, 95% CI 1.43 ~ 2.93) and insomnia (OR = 2.22, 95% CI 1.53 ~ 3.21) during the COVID-19 outbreak compared to controls. Moreover, higher COVID-19-related stress and lower levels of pre-COVID-19 anxiety, depressive and insomnia symptoms were predictors for worsened anxiety, depression and insomnia in adults with MDs, respectively. CONCLUSIONS: Our findings suggest that adverse psychological reactions and insomnia are more pronounced in adults with mental health disorders during the COVID-19 outbreak, thus more attention need to be provided.


Assuntos
COVID-19 , Coronavirus , Distúrbios do Início e da Manutenção do Sono , Adulto , Ansiedade/epidemiologia , China/epidemiologia , Estudos Transversais , Depressão , Surtos de Doenças , Humanos , Saúde Mental , SARS-CoV-2 , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estresse Psicológico
8.
J Cell Physiol ; 235(10): 7295-7308, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32043610

RESUMO

Resistance to tamoxifen remains a prominent conundrum in the therapy of hormone-sensitive breast cancer. Also, the molecular underpinnings leading to tamoxifen resistance remain unclear. In the present study, we utilized the Gene Expression Omnibus database to identify that SOX11 might exert a pivotal function in conferring tamoxifen resistance of breast cancer. SOX11 was found to be markedly upregulated at both the messenger RNA and protein levels in established MCF-7-Tam-R cells compared to the parental counterparts. Moreover, SOX11 was able to activate the transcription of slug via binding to its promoter, resulting in promoting the progress of epithelial-to-mesenchymal transition and suppressing the expression of ESR1. Downregulating SOX11 expression can restore the sensitivity to 4-hydroxytamoxifen in MCF-7-Tam-R cells. Survival analysis from large sample datasets indicated that SOX11 was closely related to poorer survival in patients with breast cancer. These findings suggest a novel feature of SOX11 in contributing to tamoxifen resistance. Hence, targeting SOX11 could be a potential therapeutic strategy to tackle tamoxifen resistance in breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Fatores de Transcrição da Família Snail/genética , Tamoxifeno/farmacologia , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Modelos Biológicos , Prognóstico , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Fatores de Transcrição SOXC/antagonistas & inibidores , Fatores de Transcrição da Família Snail/metabolismo , Regulação para Cima
9.
J Med Virol ; 92(6): 568-576, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32134116

RESUMO

By 27 February 2020, the outbreak of coronavirus disease 2019 (COVID-19) caused 82 623 confirmed cases and 2858 deaths globally, more than severe acute respiratory syndrome (SARS) (8273 cases, 775 deaths) and Middle East respiratory syndrome (MERS) (1139 cases, 431 deaths) caused in 2003 and 2013, respectively. COVID-19 has spread to 46 countries internationally. Total fatality rate of COVID-19 is estimated at 3.46% by far based on published data from the Chinese Center for Disease Control and Prevention (China CDC). Average incubation period of COVID-19 is around 6.4 days, ranges from 0 to 24 days. The basic reproductive number (R0 ) of COVID-19 ranges from 2 to 3.5 at the early phase regardless of different prediction models, which is higher than SARS and MERS. A study from China CDC showed majority of patients (80.9%) were considered asymptomatic or mild pneumonia but released large amounts of viruses at the early phase of infection, which posed enormous challenges for containing the spread of COVID-19. Nosocomial transmission was another severe problem. A total of 3019 health workers were infected by 12 February 2020, which accounted for 3.83% of total number of infections, and extremely burdened the health system, especially in Wuhan. Limited epidemiological and clinical data suggest that the disease spectrum of COVID-19 may differ from SARS or MERS. We summarize latest literatures on genetic, epidemiological, and clinical features of COVID-19 in comparison to SARS and MERS and emphasize special measures on diagnosis and potential interventions. This review will improve our understanding of the unique features of COVID-19 and enhance our control measures in the future.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Síndrome Respiratória Aguda Grave/epidemiologia , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , COVID-19 , Vacinas contra COVID-19 , China/epidemiologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Humanos , Imunização Passiva/métodos , Linfopenia/fisiopatologia , Linfopenia/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Prevalência , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/prevenção & controle , Síndrome Respiratória Aguda Grave/transmissão , Análise de Sobrevida , Trombocitopenia/fisiopatologia , Trombocitopenia/virologia , Vacinas Virais/biossíntese , Soroterapia para COVID-19
10.
J Med Virol ; 91(8): 1368-1377, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30997676

RESUMO

Accumulating evidence suggests that infections by herpesviruses might be closely linked to Alzheimer's disease (AD). Pathological hallmarks of AD brains include senile plaques induced by amyloid ß peptide (Aß) in the extracellular space and intracellular neurofibrillary tangles (NFTs) consisting of phosphorylated tau protein. The prevailing hypothesis for the mechanism of AD is amyloid cascade reaction. Recent studies revealed that infections by herpesviruses induce the similar pathological hallmarks of AD, including Aß production, phosphorylation of tau (P-tau), oxidative stress, neuroinflammation, etc. Aß peptide is regarded as one of the antimicrobial peptides, which inhibits HSV-1 replication. In the elderly, reactivation of herpesviruses might act as an initiator for amyloid cascade reaction in vulnerable individuals, triggering the neurofibrillary formation of phosphorylated tau and inducing oxidative stress and neuroinflammation, which can further contribute to the accumulation of Aß and P-tau by impairing mitochondria and autophagosome. Epidemiological studies have shown AD susceptibility genes, such as APOE-ε4 allele, are highly linked to infections by herpesviruses. Interestingly, anti-herpesviral therapy significantly reduced the risk of AD in a large population study. Given that herpesviruses are arguably the most prevalent opportunistic pathogens and often reactivate in the elderly, it is reasonable to argue reactivation of herpesviruses might be major culprits for initiating AD in individuals carrying AD susceptibility genes. In this review, we summarize epidemiological and molecular evidence that support for a hypothesis of herpesviral infections and antimicrobial protection in the development of AD, and discuss the implications for future prevention and treatment of the disease.


Assuntos
Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Infecções por Herpesviridae/complicações , Herpesviridae/imunologia , Fatores Imunológicos/metabolismo , Ativação Viral , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/toxicidade , Humanos , Fatores Imunológicos/toxicidade
11.
J Virol ; 90(10): 5187-99, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26984726

RESUMO

UNLABELLED: Mouse polyomavirus (MPyV) is a ubiquitous persistent natural mouse pathogen. A glutamic acid (E)-to-glycine (G) difference at position 91 of the VP1 capsid protein shifts the profile of tumors induced by MPyV from an epithelial to a mesenchymal cell origin. Here we asked if this tropism difference affects the MPyV-specific CD8 T cell response, which controls MPyV infection and tumorigenesis. Infection by the laboratory MPyV strain RA (VP1-91G) or a strain A2 mutant with an E-to-G substitution at VP1 residue 91 [A2(91G)] generated a markedly smaller virus-specific CD8 T cell response than that induced by A2(VP1-91E) infection. Mutant A2(91G)-infected mice showed a higher frequency of memory precursor (CD127(hi) KLRG1(lo)) CD8 T cells and a higher recall response than those of A2-infected mice. Using T cell receptor (TCR)-transgenic CD8 T cells and immunization with peptide-pulsed dendritic cells, we found that early bystander inflammation associated with A2 infection contributed to recruitment of the larger MPyV-specific CD8 T cell response. Beta interferon (IFN-ß) transcripts were induced early during A2 or A2(91G) infections. IFN-ß inhibited replication of A2 and A2(91G) in vitro Using mice lacking IFN-αß receptors (IFNAR(-/-)), we showed that type I IFNs played a role in controlling MPyV replication in vivo but differentially affected the magnitude and functionality of virus-specific CD8 T cells recruited by A2 and A2(91G) viral infections. These data indicate that type I IFNs are involved in protection against MPyV infection and that their effect on the antiviral CD8 T cell response depends on capsid-mediated tropism properties of the MPyV strain. IMPORTANCE: Isolates of the human polyomavirus JC virus from patients with the frequently fatal demyelinating brain disease progressive multifocal leukoencephalopathy (PML) carry single amino acid substitutions in the domain of the VP1 capsid protein that binds the sialic acid moiety of glycoprotein/glycolipid receptors on host cells. These VP1 mutations may alter neural cell tropism or enable escape from neutralizing antibodies. Changes in host cell tropism can affect recruitment of virus-specific CD8 T cells. Using mouse polyomavirus, we demonstrate that a single amino acid difference in VP1 known to shift viral tropism profoundly affects the quantity and quality of the anti-polyomavirus CD8 T cell response and its differentiation into memory cells. These findings raise the possibility that CD8 T cell responses to infections by human polyomaviruses may be influenced by VP1 mutations involving domains that engage host cell receptors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Proteínas do Capsídeo/genética , Interferon Tipo I/fisiologia , Polyomavirus/genética , Polyomavirus/imunologia , Tropismo Viral , Animais , Linfócitos T CD8-Positivos/fisiologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Citocinas/genética , Células Dendríticas/química , Células Dendríticas/imunologia , Regulação da Expressão Gênica , Humanos , Imunização , Memória Imunológica , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Interferon beta/genética , Interferon beta/farmacologia , Camundongos , Mutação , Polyomavirus/fisiologia , Receptores de Antígenos de Linfócitos T/imunologia , Replicação Viral
12.
J Virol ; 87(17): 9886-94, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23824803

RESUMO

Human cytomegalovirus (HCMV) lytic phase gene expression is repressed upon entry into myeloid lineage cells where the virus establishes latency. Lytic infection is not initiated because the tegument-delivered transactivator protein pp71 fails to enter the nucleus and inactivate the Daxx-mediated cellular intrinsic defense that silences the viral genome. When pp71 is expressed de novo in THP-1 monocytes, it localizes to the nucleus, inactivates the Daxx defense, and initiates lytic infection. We speculated that replacing the native viral promoter that drives pp71 expression with one that is highly and constitutively active in myeloid cells would permit pp71 de novo expression upon infection and that this newly expressed pp71 would accumulate in the nucleus, inactivate the intrinsic defense, and initiate the cascade of lytic gene expression. Surprisingly, we found that this promoter was still subject to normal silencing mechanisms in THP-1 monocytes and primary CD34(+) cells, two independent myeloid lineage cells. A second constitutively active heterologous viral promoter located in a different region of the HCMV genome was also silenced in THP-1 and CD34(+) cells. Furthermore, these two independent heterologous viral promoters inserted into three different regions of the HCMV genome in three different viral strains all required prior expression of the viral immediate early proteins for activation in fibroblasts. From this, we conclude that incorporation within the HCMV genome impacts the proclivity of heterologous viral promoters to initiate transcription. These observations have mechanistic implications for the expression of viral genes and transgenes during both lytic infection and latency.


Assuntos
Citomegalovirus/genética , Latência Viral/genética , Animais , Antígenos CD34/metabolismo , Linhagem Celular , Células Cultivadas , Citomegalovirus/fisiologia , Inativação Gênica , Genoma Viral , Interações Hospedeiro-Patógeno , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Camundongos , Monócitos/virologia , Células Mieloides/imunologia , Células Mieloides/virologia , Regiões Promotoras Genéticas , Recombinação Genética , Vírus Formadores de Foco no Baço/genética , Vírus Formadores de Foco no Baço/fisiologia , Sequências Repetidas Terminais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Latência Viral/fisiologia
13.
Mol Ther Oncolytics ; 29: 61-76, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37223114

RESUMO

Oncolytic viruses (OVs) encoding various transgenes are being evaluated for cancer immunotherapy. Diverse factors such as cytokines, immune checkpoint inhibitors, tumor-associated antigens, and T cell engagers have been exploited as transgenes. These modifications are primarily aimed to reverse the immunosuppressive tumor microenvironment. By contrast, antiviral restriction factors that inhibit the replication of OVs and result in suboptimal oncolytic activity have received far less attention. Here, we report that guanylate-binding protein 1 (GBP1) is potently induced during HSV-1 infection and restricts HSV-1 replication. Mechanistically, GBP1 remodels cytoskeletal organization to impede nuclear entry of HSV-1 genome. Previous studies have established that IpaH9.8, a bacterial E3 ubiquitin ligase, targets GBPs for proteasomal degradation. We therefore engineered an oncolytic HSV-1 to express IpaH9.8 and found that the modified OV effectively antagonized GBP1, replicated to a higher titer in vitro and showed superior antitumor activity in vivo. Our study features a strategy for improving the replication of OVs via targeting a restriction factor and achieving promising therapeutic efficacy.

14.
J Virol ; 85(17): 8798-810, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21715487

RESUMO

In response to mammalian orthoreovirus (MRV) infection, cells initiate a stress response that includes eIF2α phosphorylation and protein synthesis inhibition. We have previously shown that early in infection, MRV activation of eIF2α phosphorylation results in the formation of cellular stress granules (SGs). In this work, we show that as infection proceeds, MRV disrupts SGs despite sustained levels of phosphorylated eIF2α and, further, interferes with the induction of SGs by other stress inducers. MRV interference with SG formation occurs downstream of eIF2α phosphorylation, suggesting the virus uncouples the cellular stress signaling machinery from SG formation. We additionally examined mRNA translation in the presence of SGs induced by eIF2α phosphorylation-dependent and -independent mechanisms. We found that irrespective of eIF2α phosphorylation status, the presence of SGs in cells correlated with inhibition of viral and cellular translation. In contrast, MRV disruption of SGs correlated with the release of viral mRNAs from translational inhibition, even in the presence of phosphorylated eIF2α. Viral mRNAs were also translated in the presence of phosphorylated eIF2α in PKR(-/-) cells. These results suggest that MRV escape from host cell translational shutoff correlates with virus-induced SG disruption and occurs in the presence of phosphorylated eIF2α in a PKR-independent manner.


Assuntos
Fator de Iniciação 2 em Eucariotos/metabolismo , Interações Hospedeiro-Patógeno , Orthoreovirus de Mamíferos/fisiologia , Biossíntese de Proteínas , Proteínas Virais/biossíntese , Replicação Viral , eIF-2 Quinase/metabolismo , Linhagem Celular , Humanos , Fosforilação , RNA Mensageiro/metabolismo , RNA Viral/metabolismo
15.
Sleep Med ; 91: 262-272, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732293

RESUMO

BACKGROUND: Evidence suggests that the outbreak of the coronavirus disease 2019 (COVID-19) and the prevention/control measures for COVID-19 may cause insomnia during the acute phase of COVID-19 pandemic in China. However, it is unclear whether insomnia sustains during the later phases of the pandemic. METHODS: We searched PubMed/Medline, EMBASE, PsycINFO and China National Knowledge Infrastructure from the 27th December 2019 to the 2nd February 2021. As early stage studies on COVID-19 pandemic in China were defined as those conducted prior to April 1st, 2020, while late stage studies were those conducted after April 1st, 2020. RESULTS: A total of 98 studies with 193,889 participants were included. The pooled prevalence of insomnia symptoms among all populations was 39.1% (95% CI 36.2-42.0%); the pooled prevalence of insomnia symptoms during the early and late stages of COVID-19 in China were 37.0% (95% CI 34.1-39.9%) and 41.8% (95% CI 33.6-50.0%), respectively. Importantly, there was no significant difference regarding the prevalence of insomnia symptoms between the early and late stages of COVID-19. Meta-regression showed that healthcare workers, COVID-19 patients, patients with chronic medical conditions and patients with mental disorders had a higher prevalence of insomnia symptoms compared to the general population. This association remained significant in healthcare workers and patients with chronic medical conditions after adjusting for age, gender, areas of high or low prevalence of COVID-19 cases, anxiety and depression. CONCLUSIONS: Over one third of our sample present insomnia symptoms during the early stage of COVID-19 pandemic in China. Interestingly, prevalence of insomnia symptoms sustains high during the late stage of the pandemic despite the control of the disease and the amelioration of its adverse effects. Our findings suggest that insomnia symptoms related to COVID-19 appear to persist of over time.


Assuntos
COVID-19 , Distúrbios do Início e da Manutenção do Sono , Ansiedade/epidemiologia , COVID-19/epidemiologia , China/epidemiologia , Doença Crônica , Depressão/epidemiologia , Humanos , Pandemias , Prevalência , Distúrbios do Início e da Manutenção do Sono/epidemiologia
16.
Front Neurosci ; 16: 1047240, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36685220

RESUMO

Introduction: Transcranial electric stimulation (TES) is a neuromodulation approach that applies low-intensity electrical current to the brain and has been proposed as a treatment for insomnia. Electrostatic therapy is a kind of TES and people do not have a feeling of electrical stimuli when the voltage of static electricity is lower than 2,000 volts. However, no studies have examined the effects of electrostatic therapy on objective sleep and daytime symptoms in patients with insomnia. Materials and methods: Thirty chronic insomnia patients were included. All patients received a 6 week electrostatic therapy and three comprehensive assessments including two consecutive polysomnography (PSG) and daytime symptoms assessments, at pre-treatment, 3 week and 6 week of treatment. Insomnia Severity Index (ISI) was used to assess the severity of insomnia. Multiple sleep latency test (MSLT), Epworth Sleepiness Scale (ESS), and Flinders Fatigue Scale (FFS) were used to assess objective and self-reported daytime sleepiness and fatigue, respectively. Attention network test (ANT) was used to assess attention levels. Results: Total ISI scores decreased significantly at 3 weeks (p < 0.001) and 6 weeks (p < 0.001) after initiation of treatment. Furthermore, objective total sleep time (TST, p = 0.020) and sleep efficiency (SE, p = 0.009) increased and wake time after sleep onset (p = 0.012) decreased significantly after 6 weeks electrostatic therapy. Regarding daytime symptoms, ESS and FFS scores decreased significantly at 3 weeks (ESS, p = 0.047; FFS, p = 0.017) and 6 weeks (ESS, p = 0.008; FFS, p = 0.003) after initiation of treatment. Moreover, executive control improved significantly from pre-treatment to 3 weeks (p = 0.006) and 6 weeks (p = 0.013) and altering network improved significantly at 6 weeks (p = 0.003) after initiation of treatment. Secondary analyses showed that TST and SE improved significantly after electrostatic therapy in insomnia patients who slept < 390 min (all p-value < 0.05). However, no significant changes regarding TST and SE were observed in insomnia patients who slept ≥ 390 min. Conclusion: Electrostatic therapy improves both nighttime sleep and daytime symptoms in patients with chronic insomnia. The effect on objective sleep appears to be stronger in patient with objective short sleep duration. Electrostatic therapy might be a therapeutic choice for insomnia patients with difficulty maintaining sleep and not responding to behavioral treatments. Clinical trial registration: [www.clinicaltrials.gov], identifier [ChiCTR2100051590].

17.
Front Microbiol ; 12: 675112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012430

RESUMO

Human cytomegalovirus (HCMV) is a ubiquitous opportunistic pathogen and can be life-threatening for immunocompromised individuals. There is currently no available vaccine for the prevention of HCMV- associated diseases and most of the available antiviral drugs that target viral DNA synthesis become ineffective in treating HCMV mutants that arise after long-term use in immunocompromised patients. Here, we examined the effects of Eltanexor, a second-generation selective inhibitor of nuclear export (SINE), on HCMV replication. Eltanexor effectively inhibits HCMV replication in human foreskin fibroblasts in a dose-dependent manner. Eltanexor does not significantly inhibit viral entry and nuclear import of viral genomic DNA, but rather suppress the transcript and protein levels of viral immediate-early (IE), early (E) and late (L) genes, and abolishes the production of infectious virions. We further found Eltanexor treatment promotes proteasome-mediated degradation of XPO1, which contributes to the nuclear retention of interferon regulatory factor 3 (IRF-3), resulting in increased expression of type I interferon as well as interferon stimulating genes ISG15 and ISG54. This study reveals a novel antiviral mechanism of Eltanexor which suggests it has potential to inhibit a broad spectrum of viral pathogens.

18.
Front Genet ; 12: 798608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35058971

RESUMO

Human papillomavirus (HPV) is a causal agent for most cervical cancers. The physical status of the HPV genome in these cancers could be episomal, integrated, or both. HPV integration could serve as a biomarker for clinical diagnosis, treatment, and prognosis. Although whole-genome sequencing by next-generation sequencing (NGS) technologies, such as the Illumina sequencing platform, have been used for detecting integrated HPV genome in cervical cancer, it faces challenges of analyzing long repeats and translocated sequences. In contrast, Oxford nanopore sequencing technology can generate ultra-long reads, which could be a very useful tool for determining HPV genome sequence and its physical status in cervical cancer. As a proof of concept, in this study, we completed whole genome sequencing from a cervical cancer tissue and a CaSki cell line with Oxford Nanopore Technologies. From the cervical cancer tissue, a 7,894 bp-long HPV35 genomic sequence was assembled from 678 reads at 97-fold coverage of HPV genome, sharing 99.96% identity with the HPV sequence obtained by Sanger sequencing. A 7904 bp-long HPV16 genomic sequence was assembled from data generated from the CaSki cell line at 3857-fold coverage, sharing 99.99% identity with the reference genome (NCBI: U89348). Intriguingly, long reads generated by nanopore sequencing directly revealed chimeric cellular-viral sequences and concatemeric genomic sequences, leading to the discovery of 448 unique integration breakpoints in the CaSki cell line and 60 breakpoints in the cervical cancer sample. Taken together, nanopore sequencing is a unique tool to identify HPV sequences and would shed light on the physical status of HPV genome in its associated cancers.

19.
J Virol ; 83(21): 11090-101, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19710141

RESUMO

Infection with many mammalian orthoreovirus (MRV) strains results in shutoff of host, but not viral, protein synthesis via protein kinase R (PKR) activation and phosphorylation of translation initiation factor eIF2alpha. Following inhibition of protein synthesis, cellular mRNAs localize to discrete structures in the cytoplasm called stress granules (SGs), where they are held in a translationally inactive state. We examined MRV-infected cells to characterize SG formation in response to MRV infection. We found that SGs formed at early times following infection (2 to 6 h postinfection) in a manner dependent on phosphorylation of eIF2alpha. MRV induced SG formation in all four eIF2alpha kinase knockout cell lines, suggesting that at least two kinases are involved in induction of SGs. Inhibitors of MRV disassembly prevented MRV-induced SG formation, indicating that viral uncoating is a required step for SG formation. Neither inactivation of MRV virions by UV light nor treatment of MRV-infected cells with the translational inhibitor puromycin prevented SG formation, suggesting that viral transcription and translation are not required for SG formation. Viral cores were found to colocalize with SGs; however, cores from UV-inactivated virions did not associate with SGs, suggesting that viral core particles are recruited into SGs in a process that requires the synthesis of viral mRNA. These results demonstrate that MRV particles induce SGs in a step following viral disassembly but preceding viral mRNA transcription and that core particles are themselves recruited to SGs, suggesting that the cellular stress response may play a role in the MRV replication cycle.


Assuntos
Grânulos Citoplasmáticos/virologia , Orthoreovirus de Mamíferos/genética , Orthoreovirus de Mamíferos/metabolismo , Infecções por Reoviridae/metabolismo , Animais , Biomarcadores/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Orthoreovirus de Mamíferos/ultraestrutura , Inibidores da Síntese de Proteínas/metabolismo , Puromicina/metabolismo , Transcrição Gênica , Raios Ultravioleta , Vírion/metabolismo , Vírion/efeitos da radiação , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
20.
Cancers (Basel) ; 12(2)2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32033497

RESUMO

Gastric cancer (GC) is the fifth most frequently diagnosed cancer and the third leading cause of cancer death. Approximately 15% of GC is associated with Epstein-Barr virus (EBV). GC is largely incurable with a dismal five-year survival rate. There is an urgent need to identify new therapeutic agents for the treatment of GC. Tenovin-6 was initially identified as a p53 activator, but it was later found to inhibit autophagy flux, and the protein deacetylase activity of sirtuins. Tenovin-6 shows promising therapeutic effect in various malignancies. However, it remains unknown whether Tenovin-6 is effective for GC. In this study, we found that EBV-positive and -negative GC cell lines were sensitive to Tenovin-6 but with different response times and doses. Tenovin-6 suppressed anchorage-independent growth of GC cells. Tenovin-6 induced different levels of apoptosis and phases of cell-cycle arrest depending on the cell lines with some manifesting gap 1 (G1) and others showing synthesis (S) phase cell-cycle arrest. Mechanistically, Tenovin-6 induced autophagy or p53 activation in GC cells depending on the status of TP53 gene. However, initiation of autophagy following treatment with Tenovin-6 conferred some protective effect on numerous cells. Combined treatment with Tenovin-6 and autophagy inhibitor chloroquine increased the cytotoxic effect by inducing microtubule-associated protein 1 light chain 3B (LC3B)-II accumulation, and by enhancing apoptosis and cell-cycle arrest. These results indicated that Tenovin-6 can be used as a potential therapeutic agent for GC, but the genetic background of the cancer cells might determine the response and mechanism of action. Treatment with Tenovin-6 alone or in combination with chloroquine could be a promising therapeutic approach for GC.

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