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1.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979166

RESUMO

Monocyte-derived macrophages (mo-macs) drive immunosuppression in the tumor microenvironment (TME) and tumor-enhanced myelopoiesis in the bone marrow (BM) fuels these populations. Here, we performed paired transcriptome and chromatin analysis over the continuum of BM myeloid progenitors, circulating monocytes, and tumor-infiltrating mo-macs in mice and in patients with lung cancer to identify myeloid progenitor programs that fuel pro-tumorigenic mo-macs. Analyzing chromatin accessibility and histone mark changes, we show that lung tumors prime accessibility for Nfe2l2 (NRF2) in BM myeloid progenitors as a cytoprotective response to oxidative stress. NRF2 activity is sustained and increased during monocyte differentiation into mo-macs in the lung TME to regulate oxidative stress, in turn promoting metabolic adaptation, resistance to cell death, and contributing to immunosuppressive phenotype. NRF2 genetic deletion and pharmacological inhibition significantly reduced mo-macs' survival and immunosuppression in the TME, enabling NK and T cell therapeutic antitumor immunity and synergizing with checkpoint blockade strategies. Altogether, our study identifies a targetable epigenetic node of myeloid progenitor dysregulation that sustains immunoregulatory mo-macs in the TME.

2.
Nat Commun ; 15(1): 3729, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702330

RESUMO

The unique virus-cell interaction in Epstein-Barr virus (EBV)-associated malignancies implies targeting the viral latent-lytic switch is a promising therapeutic strategy. However, the lack of specific and efficient therapeutic agents to induce lytic cycle in these cancers is a major challenge facing clinical implementation. We develop a synthetic transcriptional activator that specifically activates endogenous BZLF1 and efficiently induces lytic reactivation in EBV-positive cancer cells. A lipid nanoparticle encapsulating nucleoside-modified mRNA which encodes a BZLF1-specific transcriptional activator (mTZ3-LNP) is synthesized for EBV-targeted therapy. Compared with conventional chemical inducers, mTZ3-LNP more efficiently activates EBV lytic gene expression in EBV-associated epithelial cancers. Here we show the potency and safety of treatment with mTZ3-LNP to suppress tumor growth in EBV-positive cancer models. The combination of mTZ3-LNP and ganciclovir yields highly selective cytotoxic effects of mRNA-based lytic induction therapy against EBV-positive tumor cells, indicating the potential of mRNA nanomedicine in the treatment of EBV-associated epithelial cancers.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Lipossomos , Nanopartículas , Transativadores , Humanos , Herpesvirus Humano 4/genética , Transativadores/metabolismo , Transativadores/genética , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Animais , Nanopartículas/química , Linhagem Celular Tumoral , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ativação Viral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Feminino
3.
EMBO J ; 43(5): 666-694, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38279026

RESUMO

The efficacy of current antimitotic cancer drugs is limited by toxicity in highly proliferative healthy tissues. A cancer-specific dependency on the microtubule motor protein KIF18A therefore makes it an attractive therapeutic target. Not all cancers require KIF18A, however, and the determinants underlying this distinction remain unclear. Here, we show that KIF18A inhibition drives a modest and widespread increase in spindle assembly checkpoint (SAC) signaling from kinetochores which can result in lethal mitotic delays. Whether cells arrest in mitosis depends on the robustness of the metaphase-to-anaphase transition, and cells predisposed with weak basal anaphase-promoting complex/cyclosome (APC/C) activity and/or persistent SAC signaling through metaphase are uniquely sensitive to KIF18A inhibition. KIF18A-dependent cancer cells exhibit hallmarks of this SAC:APC/C imbalance, including a long metaphase-to-anaphase transition, and slow mitosis overall. Together, our data reveal vulnerabilities in the cell division apparatus of cancer cells that can be exploited for therapeutic benefit.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase , Neoplasias , Humanos , Ciclossomo-Complexo Promotor de Anáfase/genética , Dineínas , Cinesinas/genética , Cinetocoros , Mitose , Neoplasias/genética
4.
Nat Cancer ; 5(1): 66-84, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38151625

RESUMO

Chromosomal instability (CIN) is a hallmark of cancer, caused by persistent errors in chromosome segregation during mitosis. Aggressive cancers like high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC) have a high frequency of CIN and TP53 mutations. Here, we show that inhibitors of the KIF18A motor protein activate the mitotic checkpoint and selectively kill chromosomally unstable cancer cells. Sensitivity to KIF18A inhibition is enriched in TP53-mutant HGSOC and TNBC cell lines with CIN features, including in a subset of CCNE1-amplified, CDK4-CDK6-inhibitor-resistant and BRCA1-altered cell line models. Our KIF18A inhibitors have minimal detrimental effects on human bone marrow cells in culture, distinct from other anti-mitotic agents. In mice, inhibition of KIF18A leads to robust anti-cancer effects with tumor regression observed in human HGSOC and TNBC models at well-tolerated doses. Collectively, our results provide a rational therapeutic strategy for selective targeting of CIN cancers via KIF18A inhibition.


Assuntos
Cinesinas , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Cinesinas/genética , Cinesinas/metabolismo , Mitose/genética , Linhagem Celular , Pontos de Checagem da Fase M do Ciclo Celular
5.
bioRxiv ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36711839

RESUMO

Targeting the α4ß7-MAdCAM-1 axis with vedolizumab (VDZ) is a front-line therapeutic paradigm in ulcerative colitis (UC). However, mechanism(s) of action (MOA) of VDZ remain relatively undefined. Here, we examined three distinct cohorts of patients with UC (n=83, n=60, and n=21), to determine the effect of VDZ on the mucosal and peripheral immune system. Transcriptomic studies with protein level validation were used to study drug MOA using conventional and transgenic murine models. We found a significant decrease in colonic and ileal naïve B and T cells and circulating gut-homing plasmablasts (ß7+) in VDZ-treated patients, pointing to gut-associated lymphoid tissue (GALT) targeting by VDZ. Murine Peyer's patches (PP) demonstrated a significant loss cellularity associated with reduction in follicular B cells, including a unique population of epithelium-associated B cells, following anti-α4ß7 antibody (mAb) administration. Photoconvertible (KikGR) mice unequivocally demonstrated impaired cellular entry into PPs in anti-α4ß7 mAb treated mice. In VDZ-treated, but not anti-tumor necrosis factor-treated UC patients, lymphoid aggregate size was significantly reduced in treatment responders compared to non-responders, with an independent validation cohort further confirming these data. GALT targeting represents a novel MOA of α4ß7-targeted therapies, with major implications for this therapeutic paradigm in UC, and for the development of new therapeutic strategies.

6.
BMC Geriatr ; 22(1): 938, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36474172

RESUMO

BACKGROUND: Few studies using rigorous clinical diagnosis have considered whether associations with cognitive decline are potentiated by interactions between genetic and modifiable risk factors. Given the increasing burden of cognitive impairment (CI) and dementia, we assessed whether Apolipoprotein E ε4 (APOE4) genotype status modifies the association between incident CI and key modifiable risk factors . METHODS: Older adults (70+) in the US were included. APOE4 status was genotyped. Risk factors for CI were self-reported. Cognitive status (normal, CI, or dementia) was assigned by clinical consensus panel. In eight separate Cox proportional hazard models, we assessed for interactions between APOE4 status and other CI risk factors. RESULT: The analytical sample included 181 participants (mean age 77.7 years; 45.9% male). APOE4 was independently associated with a greater hazard of CI in each model (Hazard Ratios [HR] between 1.81-2.66, p < 0.05) except the model evaluating educational attainment (HR 1.65, p = 0.40). The joint effects of APOE4 and high school education or less (HR 2.25, 95% CI: 1.40-3.60, p < 0.001), hypertension (HR 2.46, 95% CI: 1.28-4.73, p = 0.007), elevated depressive symptoms (HR 5.09, 95% CI: 2.59-10.02, p < 0.001), hearing loss (HR 3.44, 95% CI: 1.87-6.33, p < 0.0001), vision impairment (HR 5.14, 95% CI: 2.31-11.43, p < 0.001), smoking (HR 2.35, 95% CI: 1.24-4.47, p = 0.009), or obesity (HR 3.80, 95% CI: 2.11-6.85, p < 0.001) were associated with the hazard of incident CIND (compared to no genetic or modifiable risk factor) in separate models. The joint effect of Apolipoprotein ε4 and type 2 diabetes was not associated with CIND (HR 1.58, 95% CI: 0.67-2.48, p = 0.44). DISCUSSION: The combination of APOE4 and selected modifiable risk factors conveys a stronger association with incident CI than either type of risk factor alone.


Assuntos
Disfunção Cognitiva , Demência , Masculino , Humanos , Idoso , Feminino , Apolipoproteína E4/genética , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/genética , Fatores de Risco
8.
J Med Chem ; 65(6): 4972-4990, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35286090

RESUMO

Chromosomal instability (CIN) is a hallmark of cancer that results from errors in chromosome segregation during mitosis. Targeting of CIN-associated vulnerabilities is an emerging therapeutic strategy in drug development. KIF18A, a mitotic kinesin, has been shown to play a role in maintaining bipolar spindle integrity and promotes viability of CIN cancer cells. To explore the potential of KIF18A, a series of inhibitors was identified. Optimization of an initial hit led to the discovery of analogues that could be used as chemical probes to interrogate the role of KIF18A inhibition. Compounds 23 and 24 caused significant mitotic arrest in vivo, which was sustained for 24 h. This would be followed by cell death either in mitosis or in the subsequent interphase. Furthermore, photoaffinity labeling experiments reveal that this series of inhibitors binds at the interface of KIF18A and tubulin. This study represents the first disclosure of KIF18A inhibitors with in vivo activity.


Assuntos
Cinesinas , Neoplasias , Morte Celular , Humanos , Mitose , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fuso Acromático/metabolismo , Tubulina (Proteína)/metabolismo
9.
Genome Res ; 31(12): 2340-2353, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34663689

RESUMO

Circular RNAs (circRNAs) are abundantly expressed in cancer. Their resistance to exonucleases enables them to have potentially stable interactions with different types of biomolecules. Alternative splicing can create different circRNA isoforms that have different sequences and unequal interaction potentials. The study of circRNA function thus requires knowledge of complete circRNA sequences. Here we describe psirc, a method that can identify full-length circRNA isoforms and quantify their expression levels from RNA sequencing data. We confirm the effectiveness and computational efficiency of psirc using both simulated and actual experimental data. Applying psirc on transcriptome profiles from nasopharyngeal carcinoma and normal nasopharynx samples, we discover and validate circRNA isoforms differentially expressed between the two groups. Compared with the assumed circular isoforms derived from linear transcript annotations, some of the alternatively spliced circular isoforms have 100 times higher expression and contain substantially fewer microRNA response elements, showing the importance of quantifying full-length circRNA isoforms.

10.
Nat Commun ; 12(1): 4193, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234122

RESUMO

Interplay between EBV infection and acquired genetic alterations during nasopharyngeal carcinoma (NPC) development remains vague. Here we report a comprehensive genomic analysis of 70 NPCs, combining whole-genome sequencing (WGS) of microdissected tumor cells with EBV oncogene expression to reveal multiple aspects of cellular-viral co-operation in tumorigenesis. Genomic aberrations along with EBV-encoded LMP1 expression underpin constitutive NF-κB activation in 90% of NPCs. A similar spectrum of somatic aberrations and viral gene expression undermine innate immunity in 79% of cases and adaptive immunity in 47% of cases; mechanisms by which NPC may evade immune surveillance despite its pro-inflammatory phenotype. Additionally, genomic changes impairing TGFBR2 promote oncogenesis and stabilize EBV infection in tumor cells. Fine-mapping of CDKN2A/CDKN2B deletion breakpoints reveals homozygous MTAP deletions in 32-34% of NPCs that confer marked sensitivity to MAT2A inhibition. Our work concludes that NPC is a homogeneously NF-κB-driven and immune-protected, yet potentially druggable, cancer.


Assuntos
Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/genética , Carcinoma Nasofaríngeo/imunologia , Neoplasias Nasofaríngeas/imunologia , Evasão Tumoral/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/imunologia , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/terapia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Regulação Viral da Expressão Gênica/imunologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/patogenicidade , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Metionina Adenosiltransferase/antagonistas & inibidores , Metionina Adenosiltransferase/metabolismo , Camundongos , NF-kappa B/metabolismo , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/virologia , Nasofaringe/imunologia , Nasofaringe/patologia , Nasofaringe/cirurgia , Nasofaringe/virologia , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Deleção de Sequência , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Evasão Tumoral/efeitos dos fármacos , Sequenciamento Completo do Genoma , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Nat Commun ; 12(1): 117, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402692

RESUMO

Nasopharyngeal cancer (NPC), endemic in Southeast Asia, lacks effective diagnostic and therapeutic strategies. Even in high-income countries the 5-year survival rate for stage IV NPC is less than 40%. Here we report high somatostatin receptor 2 (SSTR2) expression in multiple clinical cohorts comprising 402 primary, locally recurrent and metastatic NPCs. We show that SSTR2 expression is induced by the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) via the NF-κB pathway. Using cell-based and preclinical rodent models, we demonstrate the therapeutic potential of SSTR2 targeting using a cytotoxic drug conjugate, PEN-221, which is found to be superior to FDA-approved SSTR2-binding cytostatic agents. Furthermore, we reveal significant correlation of SSTR expression with increased rates of survival and report in vivo uptake of the SSTR2-binding 68Ga-DOTA-peptide radioconjugate in PET-CT scanning in a clinical trial of NPC patients (NCT03670342). These findings reveal a key role in EBV-associated NPC for SSTR2 in infection, imaging, targeted therapy and survival.


Assuntos
Infecções por Vírus Epstein-Barr , Regulação Neoplásica da Expressão Gênica , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Recidiva Local de Neoplasia , Receptores de Somatostatina , Proteínas da Matriz Viral , Animais , Feminino , Humanos , Masculino , Camundongos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/mortalidade , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/crescimento & desenvolvimento , Herpesvirus Humano 4/patogenicidade , Interações Hospedeiro-Patógeno/genética , Metástase Linfática , Camundongos Nus , Terapia de Alvo Molecular , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/virologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/virologia , NF-kappa B/genética , NF-kappa B/metabolismo , Octreotida/farmacologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Receptores de Somatostatina/antagonistas & inibidores , Receptores de Somatostatina/genética , Receptores de Somatostatina/metabolismo , Transdução de Sinais , Análise de Sobrevida , Proteínas da Matriz Viral/antagonistas & inibidores , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Obstet Gynecol ; 136(5): 942-949, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33030877

RESUMO

OBJECTIVE: To use the Messick validity framework for a simulation-based assessment of vaginal hysterectomy skills. METHODS: Video recordings of physicians at different levels of training and experience performing vaginal hysterectomy on a high-fidelity vaginal surgery model were objectively assessed using a modified 10-item Vaginal Surgical Skills Index, a one-item global scale of overall performance, and a pass-fail criterion. Participants included obstetrics and gynecology trainees and faculty from five institutions. Video recordings were independently assessed by expert surgeons blinded to the identities of the study participants. RESULTS: Fifty surgeons (11 faculty, 39 trainees) were assessed. Experience level correlated strongly with both the modified Vaginal Surgical Skills Index and global scale score, with more experienced participants receiving higher scores (Pearson r=0.81, P<.001; Pearson r=0.74, P<.001). Likewise, surgical experience was also moderately correlated with the modified Vaginal Surgical Skills Index and global scale score (Pearson r=0.55, P<.001; Pearson r=0.58, P<.001). The internal consistency of the modified Vaginal Surgical Skills Index was excellent (Cronbach's alpha=0.97). Interrater reliability of the modified Vaginal Surgical Skills Index and global scale score, as measured by the intraclass correlation coefficient, was moderate to good (0.49-0.95; 0.50-0.87). Using the receiver operating characteristic curve and the pass-fail criterion, a modified Vaginal Surgical Skills Index cutoff score of 27 was found to most accurately (area under the curve 0.951, 95% CI 0.917-0.983) differentiate competent from noncompetent surgeons. CONCLUSION: We demonstrated validity evidence for using a high-fidelity vaginal surgery model with the modified Vaginal Surgical Skills Index or global scale score to assess vaginal hysterectomy skills.


Assuntos
Competência Clínica/estatística & dados numéricos , Avaliação Educacional/normas , Histerectomia Vaginal/educação , Treinamento por Simulação , Cirurgiões/estatística & dados numéricos , Adulto , Feminino , Ginecologia/educação , Humanos , Masculino , Obstetrícia/educação , Reprodutibilidade dos Testes , Cirurgiões/educação
13.
Int J Mol Sci ; 21(14)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679915

RESUMO

Gestational diabetes mellitus (GDM), characterized by a transitory form of diabetes induced by insulin resistance and pancreatic ß-cell dysfunction during pregnancy, has been identified as one of the major obstacles in achieving improved maternal and child health. Approximately 9-25% of pregnancies worldwide are impacted by the acute, long-term, and transgenerational health complications of this disease. Here, we discuss how GDM affects longstanding maternal and neonatal outcomes, as well as health risks that likely persist into future generations. In addition to the current challenges in the management and diagnosis of and the complications associated with GDM, we discuss current preclinical models of GDM to better understand the underlying pathophysiology of the disease and the timely need to increase our scientific toolbox to identify strategies to prevent and treat GDM, thereby advancing clinical care.


Assuntos
Diabetes Gestacional/etiologia , Animais , Diabetes Mellitus Experimental , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/genética , Diabetes Gestacional/terapia , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Humanos , Recém-Nascido , Programas de Rastreamento , Gravidez , Fatores de Risco , Fatores Socioeconômicos
14.
Nat Commun ; 9(1): 4663, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405107

RESUMO

The lack of representative nasopharyngeal carcinoma (NPC) models has seriously hampered research on EBV carcinogenesis and preclinical studies in NPC. Here we report the successful growth of five NPC patient-derived xenografts (PDXs) from fifty-eight attempts of transplantation of NPC specimens into NOD/SCID mice. The take rates for primary and recurrent NPC are 4.9% and 17.6%, respectively. Successful establishment of a new EBV-positive NPC cell line, NPC43, is achieved directly from patient NPC tissues by including Rho-associated coiled-coil containing kinases inhibitor (Y-27632) in culture medium. Spontaneous lytic reactivation of EBV can be observed in NPC43 upon withdrawal of Y-27632. Whole-exome sequencing (WES) reveals a close similarity in mutational profiles of these NPC PDXs with their corresponding patient NPC. Whole-genome sequencing (WGS) further delineates the genomic landscape and sequences of EBV genomes in these newly established NPC models, which supports their potential use in future studies of NPC.


Assuntos
Herpesvirus Humano 4/fisiologia , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/virologia , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Genes Virais , Herpesvirus Humano 4/genética , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Mutação/genética , Carcinoma Nasofaríngeo/genética , Filogenia , Inibidores de Proteínas Quinases/farmacologia , Vírion/metabolismo , Ativação Viral/efeitos dos fármacos , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo
15.
J Pathol ; 242(1): 62-72, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28240350

RESUMO

Undifferentiated nasopharyngeal carcinoma (NPC) is a cancer with high metastatic potential that is consistently associated with Epstein-Barr virus (EBV) infection. In this study, we have investigated the functional contribution of sphingosine-1-phosphate (S1P) signalling to the pathogenesis of NPC. We show that EBV infection or ectopic expression of the EBV-encoded latent genes (EBNA1, LMP1, and LMP2A) can up-regulate sphingosine kinase 1 (SPHK1), the key enzyme that produces S1P, in NPC cell lines. Exogenous addition of S1P promotes the migration of NPC cells through the activation of AKT; shRNA knockdown of SPHK1 resulted in a reduction in the levels of activated AKT and inhibition of cell migration. We also show that S1P receptor 3 (S1PR3) mRNA is overexpressed in EBV-positive NPC patient-derived xenografts and a subset of primary NPC tissues, and that knockdown of S1PR3 suppressed the activation of AKT and the S1P-induced migration of NPC cells. Taken together, our data point to a central role for EBV in mediating the oncogenic effects of S1P in NPC and identify S1P signalling as a potential therapeutic target in this disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Lisofosfolipídeos/fisiologia , Neoplasias Nasofaríngeas/virologia , Proteína Oncogênica v-akt/metabolismo , Receptores de Lisoesfingolipídeo/metabolismo , Esfingosina/análogos & derivados , Adulto , Idoso , Animais , Carcinoma , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Lisofosfolipídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , RNA Mensageiro/genética , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/fisiologia , Transdução de Sinais/fisiologia , Esfingosina/farmacologia , Esfingosina/fisiologia , Receptores de Esfingosina-1-Fosfato , Regulação para Cima
16.
Nat Commun ; 8: 14121, 2017 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-28098136

RESUMO

Nasopharyngeal carcinoma (NPC) is an aggressive head and neck cancer characterized by Epstein-Barr virus (EBV) infection and dense lymphocyte infiltration. The scarcity of NPC genomic data hinders the understanding of NPC biology, disease progression and rational therapy design. Here we performed whole-exome sequencing (WES) on 111 micro-dissected EBV-positive NPCs, with 15 cases subjected to further whole-genome sequencing (WGS), to determine its mutational landscape. We identified enrichment for genomic aberrations of multiple negative regulators of the NF-κB pathway, including CYLD, TRAF3, NFKBIA and NLRC5, in a total of 41% of cases. Functional analysis confirmed inactivating CYLD mutations as drivers for NPC cell growth. The EBV oncoprotein latent membrane protein 1 (LMP1) functions to constitutively activate NF-κB signalling, and we observed mutual exclusivity among tumours with somatic NF-κB pathway aberrations and LMP1-overexpression, suggesting that NF-κB activation is selected for by both somatic and viral events during NPC pathogenesis.


Assuntos
Carcinoma/genética , Infecções por Vírus Epstein-Barr/genética , Exoma , Mutação , NF-kappa B/metabolismo , Neoplasias Nasofaríngeas/genética , Transdução de Sinais , Carcinoma/metabolismo , Carcinoma/fisiopatologia , Proliferação de Células , Enzima Desubiquitinante CYLD/genética , Enzima Desubiquitinante CYLD/metabolismo , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/fisiopatologia , Infecções por Vírus Epstein-Barr/virologia , Genoma Humano , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Humanos , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/genética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/fisiopatologia , Fator 3 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Sequenciamento Completo do Genoma
17.
PLoS One ; 11(10): e0165450, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27798650

RESUMO

BACKGROUND/AIM: Live attenuated vaccines confer partial protection in pigs before the appearance of neutralizing antibodies, suggesting the contribution of cell-mediated immunity (CMI). However, PRRSV-specific T-lymphocyte responses and protective mechanisms need to be further defined. To this end, the hypothesis was tested that PRRSV-specific T-lymphocytes induced by exposure to type-2 PRRSV can recognize diverse isolates. METHODS: An IFN-gamma ELISpot assay was used to enumerate PRRSV-specific T-lymphocytes from PRRSVSD23983-infected gilts and piglets born after in utero infection against 12 serologically and genetically distinct type-1 and -2 PRRSV isolates. The IFN-gamma ELISpot assay using synthetic peptides spanning all open reading frames of PRRSVSD23983 was utilized to localize epitopes recognized by T-lymphocytes. Virus neutralization tests were carried out using the challenge strain (type-2 PRRSVSD23983) and another strain (type-2 PRRSVVR2332) with high genetic similarity to evaluate cross-reactivity of neutralizing antibodies in gilts after PRRSVSD23983 infection. RESULTS: At 72 days post infection, T-lymphocytes from one of three PRRSVSD23983-infected gilts recognized all 12 diverse PRRSV isolates, while T-lymphocytes from the other two gilts recognized all but one isolate. Furthermore, five of nine 14-day-old piglets infected in utero with PRRSVSD23983 had broadly reactive T-lymphocytes, including one piglet that recognized all 12 isolates. Overlapping peptides encompassing all open reading frames of PRRSVSD23983 were used to identify ≥28 peptides with T-lymphocyte epitopes from 10 viral proteins. This included one peptide from the M protein that was recognized by T-lymphocytes from all three gilts representing two completely mismatched MHC haplotypes. In contrast to the broadly reactive T-lymphocytes, neutralizing antibody responses were specific to the infecting PRRSVSD23983 isolate. CONCLUSION: These results demonstrated that T-lymphocytes recognizing antigenically and genetically diverse isolates were induced by infection with a type 2 PRRSV strain (SD23983). If these reponses have cytotoxic or other protective functions, they may help overcome the suboptimal heterologous protection conferred by conventional vaccines.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Linfócitos T/imunologia , Administração Intranasal , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Mapeamento de Epitopos , Epitopos/imunologia , Fases de Leitura Aberta/genética , Peptídeos/química , Peptídeos/imunologia , Filogenia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Análise de Sequência de DNA , Sus scrofa , Suínos
18.
BMC Cancer ; 16: 495, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27431799

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated epithelial malignancy that exhibits distinct geographical and ethnic prevalence. Although the contemporary therapeutic approach of radio-/chemotherapy provides excellent results for patients with early-stage disease, it is far from satisfactory for those with disease remission and distant metastasis. Promising therapeutic strategies for advanced and relapsed NPC are still lacking. We recently identified and characterized a cancer stem-like cell (CSC) subpopulation in NPC that appeared to play an important role in tumor progression. Microarray analysis revealed downregulation of several stemness-inhibiting miRNAs in these CSC cells. Among these miRNAs, miR-96 and miR-183 showed the highest fold change and were selected to elucidate their role in repressing NPC CSC properties. METHODS: MiR-96 and miR-183 expression in NPC CSCs was detected by qRT-PCR. Transient and stable transfection was performed in EBV-positive NPC C666-1 cells to examine the effects of ectopic expression of miR-96 and miR-183 on repressing cell growth and CSC properties. Anchorage-dependent (colony formation) and anchorage-independent (tumor sphere formation) growths of these miR-96 and miR-183 expressing cells were determined. Expression of multiple CSC markers and related molecules were accessed by flow cytometry and Western blotting. The tumorigenicity of the stable miR-96- and miR-183-transfected NPC cells was examined in an in vivo nude mice model. RESULTS: Downregulation of miR-96 and miR-183 was confirmed in NPC spheroids. Using transient or stable transfection, we showed that ectopic expression of miR-96 and miR-183 suppressed cell growth and tumor sphere formation in NPC. Reduced NICD3 and NICD4 in miR-96- and miR-183-expressing NPC cells suggests the involvement of the NOTCH signaling pathway in their tumor suppressive function. Finally, we showed that the tumorigenicity of cells stably expressing miR-183 was significantly inhibited in the in vivo nude mice model. CONCLUSIONS: miR-183 is a tumor-suppressive miRNA in EBV-associated NPC. Its abilities to suppress CSC properties in vitro and effectively reduce tumor growth in vivo shed light on its role as a potential therapeutic target.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Nasofaríngeas/genética , Células-Tronco Neoplásicas/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/virologia , Células-Tronco Neoplásicas/virologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptor Notch3/genética , Receptor Notch3/metabolismo , Receptor Notch4 , Receptores Notch/genética , Receptores Notch/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/metabolismo , Esferoides Celulares/virologia , Transplante Heterólogo/métodos
19.
J Med Chem ; 58(13): 5189-207, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-25970324

RESUMO

Efforts to improve upon the physical properties and metabolic stability of Aurora kinase inhibitor 14a revealed that potency against multidrug-resistant cell lines was compromised by increased polarity. Despite its high in vitro metabolic intrinsic clearance, 23r (AMG 900) showed acceptable pharmacokinetic properties and robust pharmacodynamic activity. Projecting from in vitro data to in vivo target coverage was not practical due to disjunctions between enzyme and cell data, complex and apparently contradictory indicators of binding kinetics, and unmeasurable free fraction in plasma. In contrast, it was straightforward to relate pharmacokinetics to pharmacodynamics and efficacy by following the time above a threshold concentration. On the basis of its oral route of administration, a selectivity profile that favors Aurora-driven pharmacology and its activity against multidrug-resistant cell lines, 23r was identified as a potential best-in-class Aurora kinase inhibitor. In phase 1 dose expansion studies with G-CSF support, 23r has shown promising single agent activity.


Assuntos
Aurora Quinases/antagonistas & inibidores , Descoberta de Drogas , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Ftalazinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias/enzimologia , Neoplasias/patologia , Ratos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Health Educ Behav ; 42(5): 627-32, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25842382

RESUMO

Melanoma incidence is increasing among Hispanics/Latinos in California. This community-based project reached out to a rural Hispanic/Latino community in North San Diego County to provide melanoma prevention and screening education. At a local community health fair, bilingual volunteer lay health workers led 10- to 15-minute-long information sessions on melanoma disease, risk factors, and skin self-examination techniques. Pearson chi-square analyses of participants' (N = 34) responses to pre- and postintervention evaluation surveys indicate significant increases in knowledge, risk awareness, and self-efficacy for self-screening. The results revealed that Hispanics/Latinos in a low socioeconomic stratum might be at moderate to high risk for developing melanoma. Their low annual income, low level of education, occupational sun-exposure, and lack of access to health care are likely factors that deter at-risk Hispanics/Latinos from seeking health care.


Assuntos
Promoção da Saúde , Hispânico ou Latino , Programas de Rastreamento/estatística & dados numéricos , Melanoma/etnologia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Neoplasias Cutâneas/etnologia , Adulto , California , Feminino , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/prevenção & controle , Pessoa de Meia-Idade , Fatores de Risco , População Rural , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/prevenção & controle , Fatores Socioeconômicos
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