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1.
Clin Infect Dis ; 75(1): e368-e379, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35323932

RESUMO

BACKGROUND: In locations where few people have received coronavirus disease 2019 (COVID-19) vaccines, health systems remain vulnerable to surges in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Tools to identify patients suitable for community-based management are urgently needed. METHODS: We prospectively recruited adults presenting to 2 hospitals in India with moderate symptoms of laboratory-confirmed COVID-19 to develop and validate a clinical prediction model to rule out progression to supplemental oxygen requirement. The primary outcome was defined as any of the following: SpO2 < 94%; respiratory rate > 30 BPM; SpO2/FiO2 < 400; or death. We specified a priori that each model would contain three clinical parameters (age, sex, and SpO2) and 1 of 7 shortlisted biochemical biomarkers measurable using commercially available rapid tests (C-reactive protein [CRP], D-dimer, interleukin 6 [IL-6], neutrophil-to-lymphocyte ratio [NLR], procalcitonin [PCT], soluble triggering receptor expressed on myeloid cell-1 [sTREM-1], or soluble urokinase plasminogen activator receptor [suPAR]), to ensure the models would be suitable for resource-limited settings. We evaluated discrimination, calibration, and clinical utility of the models in a held-out temporal external validation cohort. RESULTS: In total, 426 participants were recruited, of whom 89 (21.0%) met the primary outcome; 257 participants comprised the development cohort, and 166 comprised the validation cohort. The 3 models containing NLR, suPAR, or IL-6 demonstrated promising discrimination (c-statistics: 0.72-0.74) and calibration (calibration slopes: 1.01-1.05) in the validation cohort and provided greater utility than a model containing the clinical parameters alone. CONCLUSIONS: We present 3 clinical prediction models that could help clinicians identify patients with moderate COVID-19 suitable for community-based management. The models are readily implementable and of particular relevance for locations with limited resources.


Assuntos
COVID-19 , Adulto , COVID-19/diagnóstico , Progressão da Doença , Humanos , Interleucina-6 , Modelos Estatísticos , Alta do Paciente , Segurança do Paciente , Prognóstico , Estudos Prospectivos , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Reprodutibilidade dos Testes , SARS-CoV-2
2.
Proc Natl Acad Sci U S A ; 116(28): 14144-14153, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31235597

RESUMO

Epstein-Barr virus (EBV) induces histone modifications to regulate signaling pathways involved in EBV-driven tumorigenesis. To date, the regulatory mechanisms involved are poorly understood. In this study, we show that EBV infection of epithelial cells is associated with aberrant histone modification; specifically, aberrant histone bivalent switches by reducing the transcriptional activation histone mark (H3K4me3) and enhancing the suppressive mark (H3K27me3) at the promoter regions of a panel of DNA damage repair members in immortalized nasopharyngeal epithelial (NPE) cells. Sixteen DNA damage repair family members in base excision repair (BER), homologous recombination, nonhomologous end-joining, and mismatch repair (MMR) pathways showed aberrant histone bivalent switches. Among this panel of DNA repair members, MLH1, involved in MMR, was significantly down-regulated in EBV-infected NPE cells through aberrant histone bivalent switches in a promoter hypermethylation-independent manner. Functionally, expression of MLH1 correlated closely with cisplatin sensitivity both in vitro and in vivo. Moreover, seven BER members with aberrant histone bivalent switches in the EBV-positive NPE cell lines were significantly enriched in pathway analysis in a promoter hypermethylation-independent manner. This observation is further validated by their down-regulation in EBV-infected NPE cells. The in vitro comet and apurinic/apyrimidinic site assays further confirmed that EBV-infected NPE cells showed reduced DNA damage repair responsiveness. These findings suggest the importance of EBV-associated aberrant histone bivalent switch in host cells in subsequent suppression of DNA damage repair genes in a methylation-independent manner.


Assuntos
Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Código das Histonas/genética , Histonas/genética , Ilhas de CpG/genética , Dano ao DNA/genética , Metilação de DNA/genética , Reparo de Erro de Pareamento de DNA/genética , Reparo do DNA/genética , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Infecções por Vírus Epstein-Barr/patologia , Infecções por Vírus Epstein-Barr/virologia , Regulação da Expressão Gênica/genética , Herpesvirus Humano 4/patogenicidade , Recombinação Homóloga/genética , Humanos , Proteína 1 Homóloga a MutL/genética , Nasofaringe/crescimento & desenvolvimento , Nasofaringe/patologia , Nasofaringe/virologia , Regiões Promotoras Genéticas
3.
Gut ; 69(12): 2165-2179, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32217638

RESUMO

OBJECTIVE: Sporadic early-onset colorectal cancer (EOCRC) has bad prognosis, yet is poorly represented by cell line models. We examine the key mutational and transcriptomic alterations in an organoid biobank enriched in EOCRCs. DESIGN: We established paired cancer (n=32) and normal organoids (n=18) from 20 patients enriched in microsatellite-stable EOCRC. Exome and transcriptome analysis was performed. RESULTS: We observed a striking diversity of molecular phenotypes, including PTPRK-RSPO3 fusions. Transcriptionally, RSPO fusion organoids resembled normal colon organoids and were distinct from APC mutant organoids, with high BMP2 and low PTK7 expression. Single cell transcriptome analysis confirmed the similarity between RSPO fusion organoids and normal organoids, with a propensity for maturation on Wnt withdrawal, whereas the APC mutant organoids were locked in progenitor stages. CRISPR/Cas9 engineered mutation of APC in normal human colon organoids led to upregulation of PTK7 protein and suppression of BMP2, but less so with an engineered RNF43 mutation. The frequent co-occurrence of RSPO fusions with SMAD4 or BMPR1A mutation was confirmed in TCGA database searches. RNF43 mutation was found in organoid from a leukaemia survivor with a novel mutational signature; and organoids with POLE proofreading mutation displayed ultramutation. The cancer organoid genomes were stable over long culture periods, while normal human colon organoids tended to be subject to clonal dominance over time. CONCLUSIONS: These organoid models enriched in EOCRCs with linked genomic data fill a gap in existing CRC models and reveal distinct genetic profiles and novel pathway cooperativity.


Assuntos
Neoplasias Colorretais/genética , Perfil Genético , Organoides/patologia , Proteína da Polipose Adenomatosa do Colo/genética , Proteína Morfogenética Óssea 2/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Sistemas CRISPR-Cas , Moléculas de Adesão Celular/genética , Perfilação da Expressão Gênica , Fusão Gênica , Humanos , Modelos Genéticos , Mutação , Receptores Proteína Tirosina Quinases/genética , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/genética , Proteína Smad4/genética , Trombospondinas/genética , Bancos de Tecidos , Ubiquitina-Proteína Ligases/genética , Regulação para Cima , Sequenciamento do Exoma
4.
Int J Cancer ; 146(10): 2891-2900, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31609475

RESUMO

Mirror Image Polydactyly 1 (MIPOL1) is generally associated with congenital anomalies. However, its role in cancer development is poorly understood. Previously, by utilizing the functional complementation approach, microcell-mediated chromosome transfer (MMCT), a tumor suppressor gene, MIPOL1, was identified. MIPOL1 was confirmed to be downregulated in nasopharyngeal carcinoma (NPC) cells and tumor tissues, and re-expression of MIPOL1 induced tumor suppression. The aim of the current study is to further elucidate the functional tumor suppressive role of MIPOL1. In our study, with an expanded sample size of different clinical stages of NPC tumor tissues, we further confirmed the downregulation of MIPOL1 in different cancer stages. MIPOL1 re-expression down-regulated angiogenic factors and reduced phosphorylation of metastasis-associated proteins including AKT, p65, and FAK. In addition, MIPOL1 was confirmed to interact with a tumor suppressor, RhoB, and re-expression of MIPOL1 enhanced RhoB activity. The functional role of MIPOL1 was further validated by utilizing a panel of wild-type (WT) and truncated MIPOL1 expression constructs. The MIPOL1 tumor-suppressive effect can only be observed in the WT MIPOL1-expressing cells. In vitro and nude mice in vivo functional studies further confirmed the critical role of WT MIPOL1 in inhibiting migration, invasion and metastasis in NPC. Overall, our study provides strong evidence about the tumor-suppressive role of MIPOL1 in inhibiting angiogenesis and metastasis in NPC.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Proteínas Supressoras de Tumor/fisiologia , Animais , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia
5.
Proc Natl Acad Sci U S A ; 113(12): 3317-22, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-26951679

RESUMO

Multiple factors, including host genetics, environmental factors, and Epstein-Barr virus (EBV) infection, contribute to nasopharyngeal carcinoma (NPC) development. To identify genetic susceptibility genes for NPC, a whole-exome sequencing (WES) study was performed in 161 NPC cases and 895 controls of Southern Chinese descent. The gene-based burden test discovered an association between macrophage-stimulating 1 receptor (MST1R) and NPC. We identified 13 independent cases carrying the MST1R pathogenic heterozygous germ-line variants, and 53.8% of these cases were diagnosed with NPC aged at or even younger than 20 y, indicating that MST1R germline variants are relevant to disease early-age onset (EAO) (age of ≤20 y). In total, five MST1R missense variants were found in EAO cases but were rare in controls (EAO vs. control, 17.9% vs. 1.2%, P = 7.94 × 10(-12)). The validation study, including 2,160 cases and 2,433 controls, showed that the MST1R variant c.G917A:p.R306H is highly associated with NPC (odds ratio of 9.0). MST1R is predominantly expressed in the tissue-resident macrophages and is critical for innate immunity that protects organs from tissue damage and inflammation. Importantly, MST1R expression is detected in the ciliated epithelial cells in normal nasopharyngeal mucosa and plays a role in the cilia motility important for host defense. Although no somatic mutation of MST1R was identified in the sporadic NPC tumors, copy number alterations and promoter hypermethylation at MST1R were often observed. Our findings provide new insights into the pathogenesis of NPC by highlighting the involvement of the MST1R-mediated signaling pathways.


Assuntos
Exoma , Predisposição Genética para Doença , Neoplasias Nasofaríngeas/genética , Receptores Proteína Tirosina Quinases/genética , Análise de Sequência , Adolescente , Adulto , Carcinoma , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 113(40): 11283-11288, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27647909

RESUMO

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy with a unique geographical distribution. The genomic abnormalities leading to NPC pathogenesis remain unclear. In total, 135 NPC tumors were examined to characterize the mutational landscape using whole-exome sequencing and targeted resequencing. An APOBEC cytidine deaminase mutagenesis signature was revealed in the somatic mutations. Noticeably, multiple loss-of-function mutations were identified in several NF-κB signaling negative regulators NFKBIA, CYLD, and TNFAIP3 Functional studies confirmed that inhibition of NFKBIA had a significant impact on NF-κB activity and NPC cell growth. The identified loss-of-function mutations in NFKBIA leading to protein truncation contributed to the altered NF-κB activity, which is critical for NPC tumorigenesis. In addition, somatic mutations were found in several cancer-relevant pathways, including cell cycle-phase transition, cell death, EBV infection, and viral carcinogenesis. These data provide an enhanced road map for understanding the molecular basis underlying NPC.


Assuntos
Carcinoma/genética , Sequenciamento do Exoma/métodos , Mutação com Perda de Função/genética , NF-kappa B/metabolismo , Neoplasias Nasofaríngeas/genética , Transdução de Sinais/genética , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Taxa de Mutação , Inibidor de NF-kappaB alfa/metabolismo , Carcinoma Nasofaríngeo
7.
Ophthalmic Plast Reconstr Surg ; 34(3): 217-221, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28422769

RESUMO

PURPOSE: To review the outcomes of patients with optic nerve sheath meningiomas (ONSM) treated with fractionated stereotactic radiotherapy. METHODS: Patient characteristics, treatment, and outcomes were analyzed for all patients with primary and secondary ONSM treated from 2001 to 2012. Clinically significant visual acuity change was defined as a 2-line change on the Snellen eye chart from pre-fractionated stereotactic radiotherapy. RESULTS: Forty-one patients were treated: 23 patients with primary ONSM and 18 patients with secondary ONSM. The median age at diagnosis was 56 years. The median visual follow up was 3.8 years and the median radiologic follow up was 4.4 years. At diagnosis, 36% had normal vision (20/20-20/40), 10% had mild impairment (<20/40-20/60), 20% had moderate visual impairment (<20/60-20/200), 27% had severe impairment (<20/200), and 7% had no light perception. Common acute side effects were headache (32%) and nausea (15%); 15% of patients required corticosteroids during stereotactic radiotherapy. Chronic toxicities included retinopathy (7%), pituitary dysfunction (13%), chronic ocular pain (5%), and cataracts (2%). Visual acuity was stable in 65%, improved in 27%, and decreased in 8% of patients. Visual fields were stable in 70%, improved in 21%, and reduced in 9%. Actuarial 5-year local control rates were 100% for primary ONSM and 88% for secondary ONSM. Actuarial 5-year visual preservation rates were 100% for primary ONSM and 86% for secondary ONSM. CONCLUSIONS: Fractionated stereotactic radiotherapy for primary and secondary ONSM was well tolerated and provides excellent local control and visual preservation. Longer follow up is required to determine the risk of late ocular and pituitary sequelae.


Assuntos
Meningioma/radioterapia , Neoplasias do Nervo Óptico/radioterapia , Radiocirurgia/métodos , Adulto , Idoso , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acuidade Visual , Campos Visuais , Adulto Jovem
9.
Int J Cancer ; 138(1): 125-36, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26205347

RESUMO

Pan-histone deacetylase (HDAC) inhibitors, which inhibit 11 HDAC isoforms, are widely used to induce Epstein-Barr virus (EBV) lytic cycle in EBV-associated cancers in vitro and in clinical trials. Here, we hypothesized that inhibition of one or several specific HDAC isoforms by selective HDAC inhibitors could potently induce EBV lytic cycle in EBV-associated malignancies such as nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC). We found that inhibition of class I HDACs, particularly HDAC-1, -2 and -3, was sufficient to induce EBV lytic cycle in NPC and GC cells in vitro and in vivo. Among a panel of selective HDAC inhibitors, the FDA-approved HDAC inhibitor romidepsin was found to be the most potent lytic inducer, which could activate EBV lytic cycle at ∼0.5 to 5 nM (versus ∼800 nM achievable concentration in patients' plasma) in more than 75% of cells. Upregulation of p21(WAF1) , which is negatively regulated by class I HDACs, was observed before the induction of EBV lytic cycle. The upregulation of p21(WAF1) and induction of lytic cycle were abrogated by a specific inhibitor of PKC-δ but not the inhibitors of PI3K, MEK, p38 MAPK, JNK or ATM pathways. Interestingly, inhibition of HDAC-1, -2 and -3 by romidepsin or shRNA knockdown could confer susceptibility of EBV-positive epithelial cells to the treatment with ganciclovir (GCV). In conclusion, we demonstrated that inhibition of class I HDACs by romidepsin could potently induce EBV lytic cycle and mediate enhanced cell death with GCV, suggesting potential application of romidepsin for the treatment of EBV-associated cancers.


Assuntos
Antivirais/farmacologia , Depsipeptídeos/farmacologia , Ganciclovir/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Replicação Viral/efeitos dos fármacos , Acetilação , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Carcinoma , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Histona Desacetilases/genética , Histonas/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/virologia , Proteína Quinase C-delta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Ativação Viral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Cancer ; 138(1): 160-70, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26227166

RESUMO

Tumor suppressor genes (TSGs) play a prominent role in cancer and are important in the development of nasopharyngeal carcinoma (NPC), which is endemic in Southern China as well as Southeast Asia. Apart from TSGs, aberrant signalling pathways are also commonly associated with tumor progression. Unsurprisingly, the NF-κB pathway is frequently associated with angiogenesis and promoting tumor growth and development. Functional complementation studies using microcell-mediated chromosome transfer helped to identify IKBB as a putative TSG in NPC. IKBB, an inhibitor of NF-κB, has recently been shown to be inversely associated with tumor growth and metastasis via inactivation of the NF-κB pathway, but its suppressive role is still only poorly understood. This study takes the lead in revealing the suppressive role of IKBB in NPC. IKBB is silenced in the majority of NPC tumor tissues in all stages. Its suppressive role is substantiated by perturbation in tumor formation, cell migration and angiogenesis. Interestingly, IKBB not only affects the 'seed', but also influences the 'soil' by downregulating the transcriptional level of proangiogenic factors Rantes, Upar, IL6, and IL8. For the first time, our data establish the importance of a novel tumor suppressive IKBB gene in abrogating angiogenesis in NPC via the NF-κB signalling pathway, which is likely mediated by crosstalk with the Akt/Gsk3ß signalling pathway.


Assuntos
Proteínas I-kappa B/metabolismo , NF-kappa B/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Carcinoma , Linhagem Celular Tumoral , Movimento Celular/genética , Citocinas/genética , Citocinas/metabolismo , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Proteínas I-kappa B/genética , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Neovascularização Patológica/genética , Prognóstico , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Supressoras de Tumor/genética
11.
Global Health ; 11: 46, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26596963

RESUMO

BACKGROUND: Two themes consistently emerge from the broad range of academics, policymakers and opinion leaders who have proposed changes to the World Health Organization (WHO): that reform efforts are too slow, and that they do too little to strengthen WHO's capacity to facilitate cross-sectoral collaboration. This study seeks to identify possible explanations for the challenges WHO faces in addressing the broader determinants of health, and the potential opportunities for working across sectors. METHODS: This qualitative study used a mixed methods approach of semi-structured interviews and document review. Five interviewees were selected by stratified purposive sampling within a sampling frame of approximately 45 potential interviewees, and a targeted document review was conducted. All interviewees were senior WHO staff at the department director level or above. Thematic analysis was used to analyze data from interview transcripts, field notes, and the document review, and data coded during the analysis was analyzed against three central research questions. First, how does WHO conceptualize its mandate in global health? Second, what are the barriers and enablers to enhancing cross-sectoral collaboration between WHO and other intergovernmental organizations? Third, how do the dominant conceptual frames and the identified barriers and enablers to cross-sectoral collaboration interact? RESULTS: Analysis of the interviews and documents revealed three main themes: 1) WHO's role must evolve to meet the global challenges and societal changes of the 21st century; 2) WHO's cross-sectoral engagement is hampered internally by a dominant biomedical view of health, and the prevailing institutions and incentives that entrench this view; and 3) WHO's cross-sectoral engagement is hampered externally by siloed areas of focus for each intergovernmental organization, and the lack of adequate conceptual frameworks and institutional mechanisms to facilitate engagement across siloes. CONCLUSION: There are a number of external and internal pressures on WHO which have created an organizational culture and operational structure that focuses on a narrow, technical approach to global health, prioritizing disease-based, siloed interventions over more complex approaches that span sectors. The broader approach to promoting human health and wellbeing, which is conceptualized in WHO's constitution, requires cultural and institutional changes for it to be fully implemented.


Assuntos
Reforma dos Serviços de Saúde , Cultura Organizacional , Inovação Organizacional , Organização Mundial da Saúde/organização & administração , Comportamento Cooperativo , Humanos , Pesquisa Qualitativa
12.
Proc Natl Acad Sci U S A ; 108(20): 8390-5, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21540330

RESUMO

Chromosome 14 was transferred into tumorigenic nasopharyngeal carcinoma and esophageal carcinoma cell lines by a microcell-mediated chromosome transfer approach. Functional complementation of defects present in the cancer cells suppressed tumor formation. A candidate tumor-suppressor gene, cysteine-rich intestinal protein 2 (CRIP2), located in the hot spot for chromosomal loss at 14q32.3, was identified as an important candidate gene capable of functionally suppressing tumor formation. Previous studies have shown that CRIP2 is associated with development. To date, no report has provided functional evidence supporting a role for CRIP2 in tumor development. The present study provides unequivocal evidence that CRIP2 can functionally suppress tumorigenesis. CRIP2 is significantly down-regulated in nasopharyngeal carcinoma cell lines and tumors. CRIP2 reexpression functionally suppresses in vivo tumorigenesis and angiogenesis; these effects are induced by its transcription-repressor capability. It interacts with the NF-κB/p65 to inhibit its DNA-binding ability to the promoter regions of the major proangiogenesis cytokines critical for tumor progression, including IL6, IL8, and VEGF. In conclusion, we provide compelling evidence that CRIP2 acts as a transcription repressor of the NF-κB-mediated proangiogenic cytokine expression and thus functionally inhibits tumor formation and angiogenesis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Transformação Celular Neoplásica/genética , Citocinas/genética , NF-kappa B/metabolismo , Neovascularização Patológica/genética , Transcrição Gênica , Proteínas Supressoras de Tumor/genética , Proteínas Angiogênicas/análise , Linhagem Celular , Linhagem Celular Tumoral , Cromossomos Humanos Par 14 , Citocinas/fisiologia , Humanos , Proteínas com Domínio LIM , Proteínas Repressoras/fisiologia
13.
Chin J Cancer ; 33(11): 556-68, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25367335

RESUMO

The interplay between host cell genetics and Epstein-Barr virus (EBV) infection contributes to the development of nasopharyngeal carcinoma (NPC). Understanding the host genetic and epigenetic alterations and the influence of EBV on cell signaling and host gene regulation will aid in understanding the molecular pathogenesis of NPC and provide useful biomarkers and targets for diagnosis and therapy. In this review, we provide an update of the oncogenes and tumor suppressor genes associated with NPC, as well as genes associated with NPC risk including those involved in carcinogen detoxification and DNA repair. We also describe the importance of host genetics that govern the human leukocyte antigen (HLA) complex and immune responses, and we describe the impact of EBV infection on host cell signaling changes and epigenetic regulation of gene expression. High-power genomic sequencing approaches are needed to elucidate the genetic basis for inherited susceptibility to NPC and to identify the genes and pathways driving its molecular pathogenesis.


Assuntos
Epigênese Genética , Infecções por Vírus Epstein-Barr , Predisposição Genética para Doença , Neoplasias Nasofaríngeas/etiologia , Carcinoma , Genes Supressores de Tumor , Herpesvirus Humano 4/genética , Humanos , Carcinoma Nasofaríngeo , Oncogenes , Transdução de Sinais
14.
Semin Cancer Biol ; 22(2): 87-95, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22154888

RESUMO

The identification of cancer genes in sporadic cancers has been recognized as a major challenge in the field. It is clear that deletion mapping, genomic sequencing, comparative genomic hybridization, or global gene expression profiling alone would not have easily identified candidate tumor suppressor genes (TSGs) from the huge array of lost regions or genes observed in nasopharyngeal carcinoma (NPC). In addition, the epigenetically silenced genes would not have been recognized by the mapping of deleted regions. In this review, we describe how functional approaches using monochromosome transfer may be used to circumvent the above problems and identify TSGs in NPC. A few examples of selected NPC TSGs and their functional roles are reviewed. They regulate a variety of gene functions including cell growth and proliferation, adhesion, migration, invasion, epithelial-mesenchymal transition, metastasis, and angiogenesis. These studies show the advantages of using functional approaches for identification of TSGs.


Assuntos
Mapeamento Cromossômico/métodos , Predisposição Genética para Doença/genética , Neoplasias Nasofaríngeas/genética , Proteínas Supressoras de Tumor/genética , Animais , Carcinoma , Fusão Celular/métodos , Movimento Celular/genética , Humanos , Células Híbridas/metabolismo , Camundongos , Carcinoma Nasofaríngeo
15.
BMC Cell Biol ; 14: 44, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24073846

RESUMO

BACKGROUND: A few reports suggested that low levels of Wnt signaling might drive cell reprogramming, but these studies could not establish a clear relationship between Wnt signaling and self-renewal networks. There are ongoing debates as to whether and how the Wnt/ß-catenin signaling is involved in the control of pluripotency gene networks. Additionally, whether physiological ß-catenin signaling generates stem-like cells through interactions with other pathways is as yet unclear. The nasopharyngeal carcinoma HONE1 cells have low expression of ß-catenin and wild-type expression of p53, which provided a possibility to study regulatory mechanism of stemness networks induced by physiological levels of Wnt signaling in these cells. RESULTS: Introduction of increased ß-catenin signaling, haploid expression of ß-catenin under control by its natural regulators in transferred chromosome 3, resulted in activation of Wnt/ß-catenin networks and dedifferentiation in HONE1 hybrid cell lines, but not in esophageal carcinoma SLMT1 hybrid cells that had high levels of endogenous ß-catenin expression. HONE1 hybrid cells displayed stem cell-like properties, including enhancement of CD24(+) and CD44(+) populations and generation of spheres that were not observed in parental HONE1 cells. Signaling cascades were detected in HONE1 hybrid cells, including activation of p53- and RB1-mediated tumor suppressor pathways, up-regulation of Nanog-, Oct4-, Sox2-, and Klf4-mediated pluripotency networks, and altered E-cadherin expression in both in vitro and in vivo assays. qPCR array analyses further revealed interactions of physiological Wnt/ß-catenin signaling with other pathways such as epithelial-mesenchymal transition, TGF-ß, Activin, BMPR, FGFR2, and LIFR- and IL6ST-mediated cell self-renewal networks. Using ß-catenin shRNA inhibitory assays, a dominant role for ß-catenin in these cellular network activities was observed. The expression of cell surface markers such as CD9, CD24, CD44, CD90, and CD133 in generated spheres was progressively up-regulated compared to HONE1 hybrid cells. Thirty-four up-regulated components of the Wnt pathway were identified in these spheres. CONCLUSIONS: Wnt/ß-catenin signaling regulates self-renewal networks and plays a central role in the control of pluripotency genes, tumor suppressive pathways and expression of cancer stem cell markers. This current study provides a novel platform to investigate the interaction of physiological Wnt/ß-catenin signaling with stemness transition networks.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/genética , beta Catenina/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Carcinoma , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Células Híbridas/metabolismo , Células Híbridas/patologia , Fator 4 Semelhante a Kruppel , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/antagonistas & inibidores , beta Catenina/genética
16.
Proc Natl Acad Sci U S A ; 106(34): 14478-83, 2009 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-19667180

RESUMO

Chromosome 14 allelic loss is common in nasopharyngeal carcinoma (NPC) and may reflect essential tumor suppressor gene loss in tumorigenesis. An intact chromosome 14 was transferred to an NPC cell line using a microcell-mediated chromosome transfer approach. Microcell hybrids (MCHs) containing intact exogenously transferred chromosome 14 were tumor suppressive in athymic mice, demonstrating that intact chromosome 14 NPC MCHs are able to suppress tumor growth in mice. Comparative analysis of these MCHs and their derived tumor segregants identified 4 commonly eliminated tumor-suppressive CRs. Here we provide functional evidence that a gene, Mirror-Image POLydactyly 1 (MIPOL1), which maps within a single 14q13.1-13.3 CR and that hitherto has been reported to be associated only with a developmental disorder, specifically suppresses in vivo tumor formation. MIPOL1 gene expression is down-regulated in all NPC cell lines and in approximately 63% of NPC tumors via promoter hypermethylation and allelic loss. SLC25A21 and FOXA1, 2 neighboring genes mapping to this region, did not show this frequent down-regulated gene expression or promoter hypermethylation, precluding possible global methylation effects and providing further evidence that MIPOL1 plays a unique role in NPC. The protein localizes mainly to the nucleus. Re-expression of MIPOL1 in the stable transfectants induces cell cycle arrest. MIPOL1 tumor suppression is related to up-regulation of the p21(WAF1/CIP1) and p27(KIP1) protein pathways. This study provides compelling evidence that chromosome 14 harbors tumor suppressor genes associated with NPC and that a candidate gene, MIPOL1, is associated with tumor development.


Assuntos
Cromossomos Humanos Par 14/genética , Neoplasias Nasofaríngeas/genética , Proteínas Supressoras de Tumor/genética , Animais , Ciclo Celular , Linhagem Celular Transformada , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Metilação de DNA , Citometria de Fluxo , Imunofluorescência , Técnicas de Transferência de Genes , Genes Supressores de Tumor , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Nus , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Reação em Cadeia da Polimerase/métodos , Transfecção/instrumentação , Transfecção/métodos , Transplante Heterólogo , Proteínas Supressoras de Tumor/metabolismo
17.
Medicine (Baltimore) ; 100(44): e27707, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34871260

RESUMO

ABSTRACT: Diagnosing influenza in children aged 5 years and under can be challenging because of their difficulty in verbalizing symptoms. This study aimed to explore the value of the triage heart rate (HR), respiratory rate (RR), and temperature, either alone or when combined with individual symptoms and signs, in predicting influenza infection in this age group.This was a retrospective study covering 4 influenza seasons from 2017 to 2019 in an emergency department (ED) in Hong Kong. We recruited patients ≤5 years of age who had an reverse transcription polymerase chain reaction influenza test within 48 hours of ED presentation. The diagnostic performance of the triage HR, RR, and temperature was evaluated as dichotomized or categorized values with diagnostic odds ratios (DORs) calculated based on different age-appropriate thresholds. Linear discriminant analysis was performed to assess the combined discriminatory effect of age, HR, RR, and temperature as continuous variables.Of 322 patients (median age 26 months), 99 had influenza A and 13 had influenza B infection. For HR and RR dichotomized based on age-appropriate thresholds, the DORs ranged from 1.16 to 1.54 and 0.78 to 1.53, respectively. A triage temperature ≥39.0 °C had the highest DOR (3.32) among different degrees of elevation of temperature. The diagnostic criteria that were based on the presence of fever and cough and/or rhinitis symptoms had a higher DOR compared with the Centers for Disease Control and Prevention influenza-like illness criteria (4.42 vs 2.41). However, combining HR, RR, or temperature with such diagnostic criteria added very little to the diagnostic performance. The linear discriminant analysis model had a high specificity of 92.5%, but the sensitivity (18.3%) was too low for clinical use.Triage HR, RR, and temperature had limited value in the diagnosis of influenza in children ≤5 years of age in the ED. Fever and cough and/or rhinitis symptoms had a better diagnostic performance than the Centers for Disease Control and Prevention influenza-like illness criteria in predicting influenza in this age group.


Assuntos
Febre/etiologia , Influenza Humana/diagnóstico , Triagem/métodos , Pré-Escolar , Tosse/etiologia , Estudos Transversais , Serviço Hospitalar de Emergência , Febre/diagnóstico , Humanos , Lactente , Recém-Nascido , Influenza Humana/epidemiologia , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rinite/diagnóstico , Sinais Vitais
18.
Int J Cancer ; 127(2): 304-12, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19921696

RESUMO

THY1 was previously identified as a candidate tumor suppressor gene (TSG) associated with lymph node metastases in nasopharyngeal carcinoma (NPC) through functional studies. It was identified by oligonucleotide microarray analysis as an interesting differentially expressed gene. However, direct functional evidence is still lacking for THY1 being a TSG in NPC, as in vivo tumorigenicity assays have not been previously reported in our last study of THY1. In this study, a tetracycline-inducible expression vector, pETE-Bsd, was used to obtain stable transfectants of THY1. The stringent in vivo tumorigenicity assay results show that the activation of THY1 suppresses tumor formation of HONE1 cells in nude mice, and the tumor formation ability was restored in the presence of doxycycline (a tetracycline analog), when the gene is shut off. Functional inactivation of this gene is observed in all the tumors derived from the tumorigenic transfectant. The tumor suppressive effect could be repressed by knockdown of THY1 expression in nontumorigenic microcell hybrids. Further studies indicate that expression of THY1 inhibits HONE1 cell growth in vitro by arresting cells in G(0)/G(1) phase. It greatly reduces the ability for anchorage-independent growth. The invasiveness of HONE1 cells was also inhibited by the expression of THY1. These findings suggest that THY1 is a TSG in NPC, which is involved in invasion and shows an association with tumor metastasis. Taken together, THY1 clearly plays an important functional role in tumor suppression in NPC.


Assuntos
Movimento Celular , Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor/fisiologia , Neoplasias Nasofaríngeas/patologia , Antígenos Thy-1/fisiologia , Animais , Western Blotting , Adesão Celular , Ciclo Celular , Proliferação de Células , Feminino , Humanos , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Invasividade Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Injury ; 51(2): 252-259, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31836173

RESUMO

BACKGROUND: Accidents involving high-speed passenger ferries have the potential to cause mass-casualty incidents (MCIs), yet there is a lack of relevant studies available to inform hospital disaster preparedness planning. OBJECTIVE: The objective was to study the injury patterns and outcomes of MCI victims involved in high-speed passenger ferry accidents in Hong Kong waters. METHODS: A retrospective study was conducted from 1 January 2005 to 31 December 2015. All MCIs involving high-speed passenger ferries were captured from the Marine Department of Hong Kong. Victims of all age who were sent to the accident and emergency departments (A&Es) of seven public hospitals around Victoria Harbour, including three trauma centres, were identified from electronic disaster registries of the study hospitals. Data on injury patterns and outcomes were extracted from medical records with the Injury Severity Score (ISS) calculated for each victim. The Kruskal-Wallis test was used to compare medians of the ISS across different mechanisms of injury. Multivariable logistic regression was performed to identify independent predictors for major trauma (ISS≥16). RESULTS: During the study period, eight MCIs involving high-speed passenger ferries were reported and 512 victims (median age: 44 years, age range: 2-85 years) were sent to the study hospitals. The A&E triage categories were Cat 1, 3.1%; Cat 2, 4.3%; Cat 3, 19.3%; Cat 4, 72.9%; and Cat 5, 0.4%, respectively. The median ISS was 1.0 (interquartile range: 1.0-2.0). Fourteen victims (2.7%) had an ISS≥16 and age was the only independent predictor for major trauma (OR 1.06, p = 0.025, 95% CI 1.01-1.11). Trauma call was activated at A&E for 11 victims. In total, 100 victims (19.5%) were admitted to the study hospitals, including 19 (3.5%) and 15 (2.9%) who required surgery and intensive care unit stay, respectively. Eleven victims (2.1%) died, mostly due to drowning. CONCLUSION: MCIs involving high-speed passenger ferries can result in a sudden surge in demand for both A&E and in-patient care, though the majority of victims may have minor injuries. Better access to lifejackets and mandatory seatbelt use may help to reduce injuries and deaths.


Assuntos
Serviço Hospitalar de Emergência/normas , Incidentes com Feridos em Massa , Triagem/normas , Esportes Aquáticos , Ferimentos e Lesões/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Planejamento em Desastres/métodos , Feminino , Hong Kong , Hospitalização/estatística & dados numéricos , Humanos , Escala de Gravidade do Ferimento , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Centros de Traumatologia , Ferimentos e Lesões/cirurgia , Adulto Jovem
20.
Glob Public Health ; 14(2): 175-189, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29848178

RESUMO

This comparative case study investigated how two intergovernmental organisations without formal health mandates - the United Nations Development Programme (UNDP) and the World Trade Organization (WTO) - have engaged with global health issues. Triangulating insights from key institutional documents, ten semi-structured interviews with senior officials, and scholarly books tracing the history of both organisations, the study identified an evolving and broadened engagement with global health issues in UNDP and WTO. Within WTO, the dominant view was that enhancing international trade is instrumental to improving global health, although the need to resolve tensions between public health objectives and WTO agreements was recognised. For UNDP, interviewees reported that the agency gained prominence in global health for its response to HIV/AIDS in the 1990s and early 2000s. Learning from that experience, the agency has evolved and expanded its role in two respects: it has increasingly facilitated processes to provide global normative direction for global health issues such as HIV/AIDS and access to medicines, and it has expanded its focus beyond HIV/AIDS. Overall, the study findings suggest the need for seeking greater integration among international institutions, closing key global institutional gaps, and establishing a shared global institutional space for promoting action on the broader determinants of health.


Assuntos
Comércio , Saúde Global , Agências Internacionais , Cooperação Internacional , Determinantes Sociais da Saúde , Nações Unidas , Antirretrovirais , Infecções por HIV/tratamento farmacológico , Acessibilidade aos Serviços de Saúde , Humanos , Entrevistas como Assunto , Políticas , Pesquisa Qualitativa
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