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1.
Nature ; 587(7834): 377-386, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32894860

RESUMO

Here we describe the LifeTime Initiative, which aims to track, understand and target human cells during the onset and progression of complex diseases, and to analyse their response to therapy at single-cell resolution. This mission will be implemented through the development, integration and application of single-cell multi-omics and imaging, artificial intelligence and patient-derived experimental disease models during the progression from health to disease. The analysis of large molecular and clinical datasets will identify molecular mechanisms, create predictive computational models of disease progression, and reveal new drug targets and therapies. The timely detection and interception of disease embedded in an ethical and patient-centred vision will be achieved through interactions across academia, hospitals, patient associations, health data management systems and industry. The application of this strategy to key medical challenges in cancer, neurological and neuropsychiatric disorders, and infectious, chronic inflammatory and cardiovascular diseases at the single-cell level will usher in cell-based interceptive medicine in Europe over the next decade.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Atenção à Saúde/métodos , Atenção à Saúde/tendências , Medicina/métodos , Medicina/tendências , Patologia , Análise de Célula Única , Inteligência Artificial , Atenção à Saúde/ética , Atenção à Saúde/normas , Diagnóstico Precoce , Educação Médica , Europa (Continente) , Feminino , Saúde , Humanos , Legislação Médica , Masculino , Medicina/normas
2.
PLoS Genet ; 18(8): e1010376, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35994477

RESUMO

The class I histone deacetylases are essential regulators of cell fate decisions in health and disease. While pan- and class-specific HDAC inhibitors are available, these drugs do not allow a comprehensive understanding of individual HDAC function, or the therapeutic potential of isoform-specific targeting. To systematically compare the impact of individual catalytic functions of HDAC1, HDAC2 and HDAC3, we generated human HAP1 cell lines expressing catalytically inactive HDAC enzymes. Using this genetic toolbox we compare the effect of individual HDAC inhibition with the effects of class I specific inhibitors on cell viability, protein acetylation and gene expression. Individual inactivation of HDAC1 or HDAC2 has only mild effects on cell viability, while HDAC3 inactivation or loss results in DNA damage and apoptosis. Inactivation of HDAC1/HDAC2 led to increased acetylation of components of the COREST co-repressor complex, reduced deacetylase activity associated with this complex and derepression of neuronal genes. HDAC3 controls the acetylation of nuclear hormone receptor associated proteins and the expression of nuclear hormone receptor regulated genes. Acetylation of specific histone acetyltransferases and HDACs is sensitive to inactivation of HDAC1/HDAC2. Over a wide range of assays, we determined that in particular HDAC1 or HDAC2 catalytic inactivation mimics class I specific HDAC inhibitors. Importantly, we further demonstrate that catalytic inactivation of HDAC1 or HDAC2 sensitizes cells to specific cancer drugs. In summary, our systematic study revealed isoform-specific roles of HDAC1/2/3 catalytic functions. We suggest that targeted genetic inactivation of particular isoforms effectively mimics pharmacological HDAC inhibition allowing the identification of relevant HDACs as targets for therapeutic intervention.


Assuntos
Histona Desacetilase 1 , Inibidores de Histona Desacetilases , Acetilação , Histona Desacetilase 1/genética , Histona Desacetilase 1/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
3.
BMC Infect Dis ; 23(1): 1, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597074

RESUMO

BACKGROUND: Contradictory results were reported on the role of school closure/reopening on the overall SARS-CoV-2 transmission rate, as well as on which kind and level of mitigation measures implemented in schools may be effective in limiting its diffusion. Some recent studies were reassuring, showing that opening did not increase the community spread, although teachers and families are worried about the high class density. On the other hand, distance learning was associated with a negative impact on learning, sociability and psychological health, especially in vulnerable children. As it becomes clear that the SARS-CoV-2 pandemic will last for a long time, there is a high need for studies and solutions to support safe schools opening based on scientific evidence of harms and benefits. The Lolli-Methode (LM) is a strategy for epidemiological surveillance and early intervention aiming at SARS-CoV-2 outbreaks' reduction in schools, relying on polymerase chain reaction analysis of saliva samples. METHODS: In this cluster randomised trial protocol, we aim to determine whether the LM is useful to support schools opening and to reduce clusters and attack rates in schools, compared with the standard of care (SoC) surveillance by public health departments. This multicenter study will enrol 440 classes (around 8800 students, teachers and other personnel) from two countries, cluster randomised to LM or SoC. The samples from the pools will be collected and tested using PCR-based techniques. Test results will be combined with questionnaires filled in by children, parents, schoolteachers, and principals, concerning ongoing mitigation measures, their perceived psychological impact and other health and socio-economic information. An ancillary observational study will be carried out to study the prevalence of SARS-CoV-2 in schools, frequencies and size of clusters and attack rates, to compare the effectiveness of the different preventive measures adopted and to evaluate psychological issues in students and teachers in relation to the pandemic's containment measures. DISCUSSION: By the end of this study, we will have defined and characterised the applicability of the LM for SARS-CoV-2 surveillance, as well as the impact of pandemic preventive measures on children and teachers. Trial registration International Standard Randomised Controlled Trial Number: NCT05396040, 27.05.2022.


Assuntos
COVID-19 , Criança , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Surtos de Doenças , Instituições Acadêmicas , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto
4.
BMC Infect Dis ; 22(1): 676, 2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35933382

RESUMO

BACKGROUND: The incidence of high-risk human papillomavirus (hrHPV)-driven head and neck squamous cell carcinoma, in particular oropharyngeal cancers (OPC), is increasing in high-resource countries. Patients with HPV-induced cancer respond better to treatment and consequently have lower case-fatality rates than patients with HPV-unrelated OPC. These considerations highlight the importance of reliable and accurate markers to diagnose truly HPV-induced OPC. METHODS: The accuracy of three possible test strategies, i.e. (a) hrHPV DNA PCR (DNA), (b) p16(INK4a) immunohistochemistry (IHC) (p16), and (c) the combination of both tests (considering joint DNA and p16 positivity as positivity criterion), was analysed in tissue samples from 99 Belgian OPC patients enrolled in the HPV-AHEAD study. Presence of HPV E6*I mRNA (mRNA) was considered as the reference, indicating HPV etiology. RESULTS: Ninety-nine OPC patients were included, for which the positivity rates were 36.4%, 34.0% and 28.9% for DNA, p16 and mRNA, respectively. Ninety-five OPC patients had valid test results for all three tests (DNA, p16 and mRNA). Using mRNA status as the reference, DNA testing showed 100% (28/28) sensitivity, and 92.5% (62/67) specificity for the detection of HPV-driven cancer. p16 was 96.4% (27/28) sensitive and equally specific (92.5%; 62/67). The sensitivity and specificity of combined p16 + DNA testing was 96.4% (27/28) and 97.0% (65/67), respectively. In this series, p16 alone and combined p16 + DNA missed 1 in 28 HPV driven cancers, but p16 alone misclassified 5 in 67 non-HPV driven as positive, whereas combined testing would misclassify only 2 in 67. CONCLUSIONS: Single hrHPV DNA PCR and p16(INK4a) IHC are highly sensitive but less specific than using combined testing to diagnose HPV-driven OPC patients. Disease prognostication can be encouraged based on this combined test result.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Carcinoma de Células Escamosas/diagnóstico , Inibidor p16 de Quinase Dependente de Ciclina/genética , DNA Viral/análise , DNA Viral/genética , Humanos , Imuno-Histoquímica , Neoplasias Orofaríngeas/diagnóstico , Neoplasias Orofaríngeas/patologia , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase , RNA Mensageiro/análise
6.
Am J Otolaryngol ; 43(1): 103272, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34757315

RESUMO

PURPOSE: Advanced-stage laryngeal cancer is a challenging disease that needs multimodal treatment. Medical and surgical organ-preservation strategies have been developing in the last decades to spare these functions while granting cancer cure. The current work presents the experience of a tertiary-care center in conservative surgery for advanced-stage laryngeal cancer. MATERIALS AND METHODS: We collected clinical data of patients submitted to open partial horizontal laryngectomies (OPHLs) and any possible adjuvant treatment from 2005 to 2018. Outcomes were also compared to the most recent studies reporting on both medical and surgical organ-preservation strategies. RESULTS: One hundred ten patients were included in the analysis. Adjuvant therapy was employed in 51% of cases. The local control rate was 96.4%, while overall survival (OS) was 67%, and laryngo-esophageal dysfunction free survival (LEDFS) was 66%. Stage IV and vascular invasion were associated with a statistically-significant worse survival. CONCLUSIONS: OPHLs are valid as upfront treatment in fit patients affected by advanced-stage laryngeal cancer. Disease control and function preservation are granted in a significant percentage of cases, even when followed by adjuvant therapy.


Assuntos
Neoplasias Laríngeas/cirurgia , Laringectomia/métodos , Tratamentos com Preservação do Órgão/métodos , Terapia Combinada , Feminino , Humanos , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do Tratamento
7.
Int J Mol Sci ; 23(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408843

RESUMO

Head and Neck Squamous Cell Carcinoma (HNSCC) is a highly heterogeneous group of tumors characterized by an incidence of 650,000 new cases and 350,000 deaths per year worldwide and a male to female ratio of 3:1. The main risk factors are alcohol and tobacco consumption and Human Papillomavirus (HPV) infections. HNSCC cases are divided into two subgroups, the HPV-negative (HPV-) and the HPV-positive (HPV+) which have different clinicopathological and molecular profiles. However, patients are still treated with the same therapeutic regimens. It is thus of utmost importance to characterize the molecular mechanisms underlying these differences to find new biomarkers and novel therapeutic targets towards personalized therapies. Epigenetic alterations are a hallmark of cancer and can be exploited as both promising biomarkers and potential new targets. E6 and E7 HPV oncoviral proteins besides targeting p53 and pRb, impair the expression and the activity of several epigenetic regulators. While alterations in DNA methylation patterns have been well described in HPV+ and HPV- HNSCC, accurate histone post-translational modifications (hPTMs) characterization is still missing. Herein, we aim to provide an updated overview on the impact of HPV on the hPTMs landscape in HNSCC. Moreover, we will also discuss the sex and gender bias in HNSCC and how the epigenetic machinery could be involved in this process, and the importance of taking into account sex and/or gender also in this field.


Assuntos
Alphapapillomavirus , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Epigênese Genética , Feminino , Neoplasias de Cabeça e Pescoço/genética , Histonas/genética , Humanos , Masculino , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Caracteres Sexuais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
8.
Int J Mol Sci ; 23(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35742918

RESUMO

In human medicine, the progression from early neoplasia development to either complete resolution of tumorigenesis and associated inflammation or chronicity and fatal outcomes remain difficult to predict. Resolution of inflammation is an active process that stimulates the termination of the inflammatory response and promotes return to homeostasis, while failure in resolution contributes to the development of a number of diseases. To understand how resolution pathways contribute to tumorigenesis, we defined and employed a cumulative score based on the expression level of genes involved in synthesis, signaling, and metabolism of the D-series resolvin (RvD). This score was used for comparative analyses of clinical, cellular, and molecular features of tumors, based on RNA-sequencing (RNA-seq) datasets collected within The Cancer Genome Atlas (TCGA) program. Our results indicate that higher RvD scores are associated with better clinical outcome of patients with head and neck squamous cell carcinoma (HNSC), and with molecular and cellular signatures indicative of enhanced anti-tumor immunity and better response to immune-checkpoint inhibitors (ICI), also in human papilloma virus (HPV) negative HNSC subtypes. Thus, higher activity of the RvD pathway identifies patients with improved resolution and a more efficient immune reaction against cancer.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Biomarcadores Tumorais/genética , Carcinogênese , Carcinoma de Células Escamosas/metabolismo , Transformação Celular Neoplásica , Expressão Gênica , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Inflamação , Carcinoma de Células Escamosas de Cabeça e Pescoço
9.
J Virol ; 94(19)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669341

RESUMO

Adeno-associated virus (AAV) has proven to be a promising candidate for gene therapy due to its nonpathogenic nature, ease of production, and broad tissue tropism. However, its transduction capabilities are not optimal due to the interaction with various host factors within the cell. In a previous study, we identified members of the small ubiquitin-like modifier (SUMO) pathway as significant restriction factors in AAV gene transduction. In the present study, we explored the scope of this restriction by focusing on the AAV capsid and host cell proteins as targets. We show that during vector production, the capsid protein VP2 becomes SUMOylated, as indicated by deletion and point mutations of VP2 or the obstruction of its N terminus via the addition of a tag. We observed that SUMOylated AAV capsids display higher stability than non-SUMOylated capsids. Prevention of capsid SUMOylation by VP2 mutations did not abolish transduction restriction by SUMOylation; however, it reduced activation of gene transduction by shutdown of the cellular SUMOylation pathway. This indicates a link between capsid SUMOylation and SUMOylation of cellular proteins in restricting gene transduction. Infection with AAV triggers general SUMOylation of cellular proteins. In particular, the DAXX protein, a putative host cell restriction factor that can become SUMOylated, is able to restrict AAV gene transduction by reducing the intracellular accumulation of AAV vectors. We also observe that the coexpression of a SUMOylation inhibitor with an AAV2 reporter gene vector increased gene transduction significantly.IMPORTANCE Host factors within the cell are the major mode of restriction of adeno-associated virus (AAV) and keep it from fulfilling its maximum potential as a gene therapy vector. A better understanding of the intricacies of restriction would enable the engineering of better vectors. Via a genome-wide short interfering RNA screen, we identified that proteins of the small ubiquitin-like modifier (SUMO) pathway play an important role in AAV restriction. In this study, we investigate whether this restriction is targeted to the AAV directly or indirectly through host cell factors. The results indicate that both targets act in concert to restrict AAV.


Assuntos
Capsídeo/metabolismo , Dependovirus/genética , Dependovirus/fisiologia , Sumoilação/fisiologia , Transdução Genética , Células A549 , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Terapia Genética , Vetores Genéticos/genética , Células HEK293 , Células HeLa , Humanos , Sumoilação/genética
10.
Am J Otolaryngol ; 42(2): 102861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33445041

RESUMO

PURPOSE: Laryngeal dysplasia represents a series of precancerous lesions, observed as laryngeal leukoplakia. General agreement has been lacking for their management and treatment ranging from simple biopsy to complete excision with cold blade/laser. In this work, we aim at providing the oncological outcomes of patients affected by laryngeal dysplasia, treated with a single modality, and at identifying clinical parameters predictive of malignant transformation. MATERIALS AND METHODS: We performed a retrospective analysis of patients treated with transoral laser microsurgery between January 2005 and December 2015 in a tertiary comprehensive cancer centre. Data were collected about smoke and alcohol habits, site of the laryngeal lesion, surgical outcomes and progression to invasive squamous cell carcinoma. RESULTS: The grade of dysplasia, margins' status and smoke habit were not associated with a significantly worse DFS and a higher risk of invasive SCC. We identified three parameters (supraglottic involvement, multifocality and history of more than one recurrence of dysplasia) that have a significant prognostic value. CONCLUSIONS: On the base of these clinical parameters, a more intensive follow-up might be warranted for high-risk patients.


Assuntos
Institutos de Câncer/estatística & dados numéricos , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Transformação Celular Neoplásica , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/terapia , Lesões Pré-Cancerosas , Centros de Atenção Terciária/estatística & dados numéricos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Progressão da Doença , Feminino , Humanos , Neoplasias Laríngeas/epidemiologia , Neoplasias Laríngeas/etiologia , Masculino , Razão de Chances , Estudos Retrospectivos , Risco , Fumar/efeitos adversos , Resultado do Tratamento
11.
Curr Issues Mol Biol ; 35: 1-16, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31422930

RESUMO

Small ubiquitin-like modifier (SUMO)ylation is a crucial post-translational modification that controls functions of a wide collection of proteins and biological processes. Hence, given its pleiotropic role, viruses have developed many approaches to usurp SUMO conjugation to exploit the cellular host environment for their own benefit. Consistently, cancer cells also frequently impact on SUMO to force cellular transformation, underlining the importance of SUMO in health and diseases. Therefore, after a brief introduction to the multistep SUMOylation pathway, in this review we will focus our attention on several examples of strategies adopted by oncogenic viruses to hijack SUMOylation in order to promote infection, persistence and malignant transformation of host cells.


Assuntos
Neoplasias/metabolismo , Neoplasias/virologia , Retroviridae/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sumoilação , Cromatina/genética , Cromatina/metabolismo , Hepacivirus/genética , Hepacivirus/metabolismo , Hepacivirus/patogenicidade , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/patogenicidade , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Herpesvirus Humano 4/patogenicidade , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Herpesvirus Humano 8/patogenicidade , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Humanos , Poliomavírus das Células de Merkel/genética , Poliomavírus das Células de Merkel/metabolismo , Poliomavírus das Células de Merkel/patogenicidade , Neoplasias/genética , Papillomaviridae/genética , Papillomaviridae/metabolismo , Papillomaviridae/patogenicidade , Retroviridae/genética , Retroviridae/crescimento & desenvolvimento , Retroviridae/patogenicidade , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética , Ubiquitina-Proteína Ligases/metabolismo
12.
Br J Cancer ; 122(3): 306-314, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31708575

RESUMO

The human papillomavirus (HPV) family includes more than 170 different types of virus that infect stratified epithelium. High-risk HPV is well established as the primary cause of cervical cancer, but in recent years, a clear role for this virus in other malignancies is also emerging. Indeed, HPV plays a pathogenic role in a subset of head and neck cancers-mostly cancers of the oropharynx-with distinct epidemiological, clinical and molecular characteristics compared with head and neck cancers not caused by HPV. This review summarises our current understanding of HPV in these cancers, specifically detailing HPV infection in head and neck cancers within different racial/ethnic subpopulations, and the differences in various aspects of these diseases between women and men. Finally, we provide an outlook for this disease, in terms of clinical management, and consider the issues of 'diagnostic biomarkers' and targeted therapies.


Assuntos
Neoplasias de Cabeça e Pescoço/epidemiologia , Infecções por Papillomavirus/epidemiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , DNA Viral/análise , Etnicidade , Neoplasias de Cabeça e Pescoço/etnologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/patogenicidade , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/patogenicidade , Humanos , Hibridização In Situ , Papillomaviridae/genética , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/etnologia , Infecções por Papillomavirus/virologia , Prevalência , Prognóstico , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Fatores Sexuais , Carcinoma de Células Escamosas de Cabeça e Pescoço/etnologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia
13.
Mol Cell ; 46(4): 382-3, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22633485

RESUMO

In the current issue of Molecular Cell, de la Vega et al. (2012) propose an intriguing model for HIPK2 posttranslational modifications in response to oxidative stress, explaining how HIPK2 can possess both prosurvival as well as proapoptotic activities.

14.
Nucleic Acids Res ; 46(8): 3817-3832, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618087

RESUMO

Histone post-translational modifications (PTMs) generate a complex combinatorial code that regulates gene expression and nuclear functions, and whose deregulation has been documented in different types of cancers. Therefore, the availability of relevant culture models that can be manipulated and that retain the epigenetic features of the tissue of origin is absolutely crucial for studying the epigenetic mechanisms underlying cancer and testing epigenetic drugs. In this study, we took advantage of quantitative mass spectrometry to comprehensively profile histone PTMs in patient tumor tissues, primary cultures and cell lines from three representative tumor models, breast cancer, glioblastoma and ovarian cancer, revealing an extensive and systematic rewiring of histone marks in cell culture conditions, which includes a decrease of H3K27me2/me3, H3K79me1/me2 and H3K9ac/K14ac, and an increase of H3K36me1/me2. While some changes occur in short-term primary cultures, most of them are instead time-dependent and appear only in long-term cultures. Remarkably, such changes mostly revert in cell line- and primary cell-derived in vivo xenograft models. Taken together, these results support the use of xenografts as the most representative models of in vivo epigenetic processes, suggesting caution when using cultured cells, in particular cell lines and long-term primary cultures, for epigenetic investigations.


Assuntos
Código das Histonas , Histonas/metabolismo , Neoplasias/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Xenoenxertos , Código das Histonas/genética , Histonas/genética , Humanos , Camundongos , Camundongos Nus , Modelos Biológicos , Neoplasias/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Processamento de Proteína Pós-Traducional , Proteômica , Células Tumorais Cultivadas
15.
Br J Cancer ; 120(6): 658-667, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30765872

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR) overexpression is associated with the development of head and neck cancer (HNC) and represents one of the main therapeutic targets for this disease. The use of EGFR inhibitors has limited efficacy due to their primary and acquired resistance, partially because of increased epithelial to mesenchymal transition (EMT). The HDAC inhibitor SAHA has been shown to revert EMT in different tumours, including HNC. In this study, we investigated the cooperative role of SAHA and the EGFR tyrosine kinase inhibitor gefitinib in both HPV-positive and HPV-negative HNC cell lines. METHODS: A panel of 12 HPV-positive and HPV-negative HNC cell lines were screened for cell viability upon treatment with SAHA, gefitinib and the combination of the two. Epithelial/mesenchymal marker expression, as well as activation of signalling pathway, were assessed upon SAHA treatment. ΔNp63α silencing with shRNA lentiviral particles was used to determine its role in cell proliferation, migration and TGFß pathway activation. RESULTS: We found that both SAHA and gefitinib have antitumour activity in both HPV-positive and HPV-negative HNC cell lines and that their combination has a synergistic effect in inhibiting cell growth. SAHA treatment reverts EMT and inhibits the expression of the transcription factor ΔNp63α. Suppression of ΔNp63α reduces EGFR protein levels and decreases cell proliferation and TGFß-dependent migration in both HPV-positive and HPV-negative HNC cell lines. CONCLUSIONS: Our results, by giving a clear molecular mechanism at the basis of the antitumour activity of SAHA in HNC cell lines, provide a rationale for the clinical evaluation of SAHA in combination with gefitinib in both HPV-positive and HPV-negative HNC patients. Further knowledge is key to devising additional lines of combinatorial treatment strategies for this disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Gefitinibe/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Vorinostat/farmacologia , Sinergismo Farmacológico , Gefitinibe/administração & dosagem , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/farmacologia , Humanos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/virologia , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Vorinostat/administração & dosagem
16.
PLoS Pathog ; 13(3): e1006262, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28253371

RESUMO

UBC9, the sole E2-conjugating enzyme required for SUMOylation, is a key regulator of essential cellular functions and, as such, is frequently altered in cancers. Along these lines, we recently reported that its expression gradually increases during early stages of human papillomavirus (HPV)-mediated cervical lesions transformation. However, a better understanding of how UBC9 is exploited by transforming viral oncoproteins is still needed. In the present study, we show that in human samples HPV drives UBC9 up-regulation also in very early steps of head and neck tumorigenesis, pointing to the important role for UBC9 in the HPV-mediated carcinogenic program. Moreover, using HPV-infected pre-cancerous tissues and primary human keratinocytes as the natural host of the virus, we investigate the pathological meaning and the cellular mechanisms responsible for UBC9 de-regulation in an oncoviral context. Our results show that UBC9 overexpression is promoted by transforming viral proteins to increase host cells' resistance to apoptosis. In addition, ultrastuctural, pharmacological and genetic approaches crucially unveil that UBC9 is physiologically targeted by autophagy in human cells. However, the presence of HPV E6/E7 oncoproteins negatively impacts the autophagic process through selective inhibition of autophagosome-lysosome fusion, finally leading to p53 dependent UBC9 accumulation during viral-induced cellular transformation. Therefore, our study elucidates how UBC9 is manipulated by HPV oncoproteins, details the physiological mechanism by which UBC9 is degraded in cells, and identifies how HPV E6/E7 impact on autophagy. These findings point to UBC9 and autophagy as novel hallmarks of HPV oncogenesis, and open innovative avenues towards the treatment of HPV-related malignancies.


Assuntos
Autofagia/fisiologia , Transformação Celular Viral/fisiologia , Infecções por Papillomavirus/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Apoptose , Transformação Celular Neoplásica , Feminino , Citometria de Fluxo , Humanos , Immunoblotting , Imuno-Histoquímica , Microscopia Confocal , Proteínas Oncogênicas Virais , Papillomaviridae/metabolismo , Infecções por Papillomavirus/patologia , Reação em Cadeia da Polimerase , Transdução Genética , Transfecção
18.
Int J Mol Sci ; 19(6)2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29914057

RESUMO

Human papilloma viruses (HPVs) are a group of double-stranded DNA viruses known to be the primary cause of cervical cancer. In addition, evidence has now established their role in non-melanoma skin cancers, head and neck cancer (HNC), and the development of other anogenital malignancies. The prevalence of HPV-related HNC, in particular oropharyngeal cancers, is rapidly increasing, foreseeing that HPV-positive oropharyngeal cancers will outnumber uterine cervical cancers in the next 15⁻20 years. Therefore, despite the successful advent of vaccines originally licensed for cervical cancer prevention, HPV burden is still very high, and a better understanding of HPV biology is urgently needed. Autophagy is the physiological cellular route that accounts for removal, degradation, and recycling of damaged organelles, proteins, and lipids in lysosomal vacuoles. In addition to this scavenger function, autophagy plays a fundamental role during viral infections and cancers and is, therefore, frequently exploited by viruses to their own benefit. Recently, a link between HPV and autophagy has clearly emerged, leading to the conceivable development of novel anti-viral strategies aimed at restraining HPV infectivity. Here, recent findings on how oncogenic HPV16 usurp autophagy are described, highlighting similarities and differences with mechanisms adopted by other oncoviruses.


Assuntos
Autofagia , Papillomaviridae/patogenicidade , Neoplasias do Colo do Útero/virologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Papillomaviridae/genética , Papillomaviridae/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
19.
Int J Cancer ; 141(1): 143-151, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369859

RESUMO

Mucosal high-risk (HR) human papillomaviruses (HPV) cause a subset of head and neck cancers (HNC). The HPV-attributable fraction of HNC varies substantially between countries. Although HNC has a very high incidence in the Indian subcontinent, information on the contribution of HPV infection is limited. Here, we evaluated the HPV-attributable fraction in HNC (N = 364) collected in a central region of India. HNC from three different anatomical subsites were included, namely, oral cavity (n = 252), oropharynx (n = 53) and hypopharynx/larynx (n = 59). In this retrospective study, HPV-driven HNC were defined by presence of both viral DNA and RNA. Overexpression of p16INK4a was also evaluated. HR-HPV DNA was detected in 13.7% of the cases; however, only 2.7% were positive for both HPV DNA and RNA. The highest percentage of HPV DNA/RNA double positivity was found in oropharynx (9.4%), followed by larynx (1.7%) and oral cavity (1.6%) (p = 0.02). More than half of HPV DNA/RNA-positive cases were p16INK4a -negative, while a considerable number of HPV RNA-negative cases were p16INK4a -positive (17.9%). HPV16 was the major type associated with HNC (60.0%), although cases positive for HPV18, 35 and 56 were also detected. Our data indicate that the proportion and types of mucosal HR-HPV associated with HNC in this central Indian region differ from those in other (developed) parts of the world. This may be explained by differences in smoking and/or sexual behaviour compared with North America and northern Europe. Moreover, we show that p16INK4a staining appeared not to be a good surrogate marker of HPV transformation in the Indian HNC cases.


Assuntos
Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/virologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Adulto , Idoso , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia
20.
Proc Natl Acad Sci U S A ; 110(45): 18168-73, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24145437

RESUMO

The tumor suppressor VHL (von Hippel-Lindau) protein is a substrate receptor for Ubiquitin Cullin Ring Ligase complexes (CRLs), containing a BC-box domain that associates to the adaptor Elongin B/C. VHL targets hypoxia-inducible factor 1α to proteasome-dependent degradation. Gam1 is an adenoviral protein, which also possesses a BC-box domain that interacts with the host Elongin B/C, thereby acting as a viral substrate receptor. Gam1 associates with both Cullin2 and Cullin5 to form CRL complexes targeting the host protein SUMO enzyme SAE1 for proteasomal degradation. We show that Gam1 protein expression induces VHL protein degradation leading to hypoxia-inducible factor 1α stabilization and induction of its downstream targets. We also characterize the CRL-dependent mechanism that drives VHL protein degradation via proteasome. Interestingly, expression of Suppressor of Cytokine Signaling (SOCS) domain-containing viral proteins and cellular BC-box proteins leads to VHL protein degradation, in a SOCS domain-containing manner. Our work underscores the exquisite ability of viral domains to uncover new regulatory mechanisms by hijacking key cellular proteins.


Assuntos
Proteólise , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Linhagem Celular Tumoral , Proteínas Culina/genética , Proteínas Culina/metabolismo , Primers do DNA/genética , Elonguina , Técnicas de Silenciamento de Genes , Humanos , Immunoblotting , Imunoprecipitação , Luciferases , Estrutura Terciária de Proteína , Reação em Cadeia da Polimerase em Tempo Real , Proteína 1 Supressora da Sinalização de Citocina , Fatores de Transcrição/metabolismo , Proteínas Virais/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/fisiologia
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