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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Associação entre o papiloma vírus humano e o carcinoma epidermóide de orofaringe : um estudo de caso-controle

Schwartsmann, Carla Cuenca January 2013 (has links)
Introdução: A incidência do carcinoma epidermóide de orofaringe (CEO) aumentou em todo o mundo nos últimos 30 anos. Estudos identificaram o papiloma vírus humano (HPV) como um fator de risco para essa neoplasia. Objetivos: O objetivo do presente estudo foi verificar a frequência do HPV em pacientes com CEO e em pacientes sem neoplasia maligna e avaliar a existência de uma diferença estatisticamente significativa na frequência do HPV entre os dois grupos. O objetivo secundário foi estudar a correlação entre a infecção pelo HPV e a localização do tumor na orofaringe, o estadiamento clínico e o grau de diferenciação tumoral. Métodos: Foi realizado um estudo de caso-controle com 59 pacientes com CEO e 54 pacientes sem neoplasia, no qual foram analisados os blocos de parafina contendo material tumoral e tecido não neoplásico. Foram analisadas respectivamente a frequência do HPV e sua atividade viral utilizando a técnica de hibridização in situ cromogênica (CISH) para HPV de baixo risco (BR) e alto risco (AR) e a expressão imunoistoquímica da proteína P16. Resultados: A frequência do HPV foi maior no grupo caso em comparação ao grupo controle quando utilizamos a expressão imunoistoquímica da proteína P16 como método de detecção isolado (OR=10,3; P<0,001) e quando utilizamos a CISH e a expressão imunoistoquímica da proteína P16 em conjunto (OR=21,4; P<0,001). A CISH isoladamente não mostrou uma diferença estatisticamente significativa na frequência do HPV entre os grupos estudados (P=0,572). A localização tumoral na orofaringe e o estadiamento clínico não mostraram correlação com a infecção pelo HPV em nenhum dos métodos utilizados, assim como o grau de diferenciação tumoral (P>0,20). Conclusão: Utilizando-se a técnica de imunoistoquímica para P16 isolada ou combinada com a técnica de CISH, observou-se uma maior positividade para o HPV no grupo de pacientes com CEO. A localização do tumor na orofaringe, o estadiamento clínico e o grau de diferenciação tumoral não tiveram correlação com a positividade para o HPV. / Introduction: The incidence of oropharyngeal squamous cell carcinoma (OSCC) has increased worldwide over the last 30 years. Studies have identified human papillomavirus (HPV) infection as a risk factor for OSCC. Objectives: To compare the frequency of HPV infection in patients with OSCC and patients with benign oral or oropharyngeal disease and ascertain whether a statistically significant difference in HPV frequency exists between these two groups. As a secondary objective, to assess potential correlations between HPV positivity, anatomic site of OSCC, tumor staging, and degree of tumor differentiation. Methods: Case-control study. The sample comprised 59 patients with OSCC and 54 non-OSCC controls who underwent surgery for benign oral or oropharyngeal conditions. Paraffin-embedded specimens from cases and controls were tested for HPV positivity by chromogenic in situ hybridization (CISH) for low-risk (LR) and high-risk (HR) HPV, and HPV activity was assessed by P16 immunohistochemistry (IHC). Results: The frequency of HPV positivity was higher in the case group than in the control group when assessed by P16 IHC alone (OR=10.3, P<0.001) or by CISH and P16 IHC in combination (OR=21.4, P<0.001). CISH alone did not detect any significant between-group difference in HPV frequency (P=0.572). Tumor site, staging, and differentiation did not correlate with HPV positivity with any of the methods employed (P>0.20). Conclusion: Using a P16 IHC assay alone or combined with CISH, the authors showed a higher rate of HPV positivity among patients with OSCC, as compared with patients with benign disease. Tumor site within the oropharynx, tumor stage, and degree of differentiation did not correlate with HPV positivity.
12

Associação entre o papiloma vírus humano e o carcinoma epidermóide de orofaringe : um estudo de caso-controle

Schwartsmann, Carla Cuenca January 2013 (has links)
Introdução: A incidência do carcinoma epidermóide de orofaringe (CEO) aumentou em todo o mundo nos últimos 30 anos. Estudos identificaram o papiloma vírus humano (HPV) como um fator de risco para essa neoplasia. Objetivos: O objetivo do presente estudo foi verificar a frequência do HPV em pacientes com CEO e em pacientes sem neoplasia maligna e avaliar a existência de uma diferença estatisticamente significativa na frequência do HPV entre os dois grupos. O objetivo secundário foi estudar a correlação entre a infecção pelo HPV e a localização do tumor na orofaringe, o estadiamento clínico e o grau de diferenciação tumoral. Métodos: Foi realizado um estudo de caso-controle com 59 pacientes com CEO e 54 pacientes sem neoplasia, no qual foram analisados os blocos de parafina contendo material tumoral e tecido não neoplásico. Foram analisadas respectivamente a frequência do HPV e sua atividade viral utilizando a técnica de hibridização in situ cromogênica (CISH) para HPV de baixo risco (BR) e alto risco (AR) e a expressão imunoistoquímica da proteína P16. Resultados: A frequência do HPV foi maior no grupo caso em comparação ao grupo controle quando utilizamos a expressão imunoistoquímica da proteína P16 como método de detecção isolado (OR=10,3; P<0,001) e quando utilizamos a CISH e a expressão imunoistoquímica da proteína P16 em conjunto (OR=21,4; P<0,001). A CISH isoladamente não mostrou uma diferença estatisticamente significativa na frequência do HPV entre os grupos estudados (P=0,572). A localização tumoral na orofaringe e o estadiamento clínico não mostraram correlação com a infecção pelo HPV em nenhum dos métodos utilizados, assim como o grau de diferenciação tumoral (P>0,20). Conclusão: Utilizando-se a técnica de imunoistoquímica para P16 isolada ou combinada com a técnica de CISH, observou-se uma maior positividade para o HPV no grupo de pacientes com CEO. A localização do tumor na orofaringe, o estadiamento clínico e o grau de diferenciação tumoral não tiveram correlação com a positividade para o HPV. / Introduction: The incidence of oropharyngeal squamous cell carcinoma (OSCC) has increased worldwide over the last 30 years. Studies have identified human papillomavirus (HPV) infection as a risk factor for OSCC. Objectives: To compare the frequency of HPV infection in patients with OSCC and patients with benign oral or oropharyngeal disease and ascertain whether a statistically significant difference in HPV frequency exists between these two groups. As a secondary objective, to assess potential correlations between HPV positivity, anatomic site of OSCC, tumor staging, and degree of tumor differentiation. Methods: Case-control study. The sample comprised 59 patients with OSCC and 54 non-OSCC controls who underwent surgery for benign oral or oropharyngeal conditions. Paraffin-embedded specimens from cases and controls were tested for HPV positivity by chromogenic in situ hybridization (CISH) for low-risk (LR) and high-risk (HR) HPV, and HPV activity was assessed by P16 immunohistochemistry (IHC). Results: The frequency of HPV positivity was higher in the case group than in the control group when assessed by P16 IHC alone (OR=10.3, P<0.001) or by CISH and P16 IHC in combination (OR=21.4, P<0.001). CISH alone did not detect any significant between-group difference in HPV frequency (P=0.572). Tumor site, staging, and differentiation did not correlate with HPV positivity with any of the methods employed (P>0.20). Conclusion: Using a P16 IHC assay alone or combined with CISH, the authors showed a higher rate of HPV positivity among patients with OSCC, as compared with patients with benign disease. Tumor site within the oropharynx, tumor stage, and degree of differentiation did not correlate with HPV positivity.
13

Avaliação da prevalência do Papíloma Humano (HPV) em saliva de pacientes portadores do HIV

AZEVEDO, Karinne Silva 27 August 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-12-12T14:11:56Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTACAO PARA BIBLIOTECA CENTRAL - KARINNE AZEVEDO.pdf: 2052240 bytes, checksum: fba514c37249c7db73fcf51a37fa21ff (MD5) / Made available in DSpace on 2016-12-12T14:11:56Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTACAO PARA BIBLIOTECA CENTRAL - KARINNE AZEVEDO.pdf: 2052240 bytes, checksum: fba514c37249c7db73fcf51a37fa21ff (MD5) Previous issue date: 2015-08-27 / CAPES / Identificar a presença dos sorotipos de alto risco do Papilomavírus Humano (HPV) na saliva de pacientes portadores do vírus HIV. A amostra de 90 pacientes foi oriunda de dois centros de referência em tratamento de ISTs da cidade do Recife, PE, Brasil. Uma entrevista foi realizada para identificar o perfil da amostra, sendo realizada uma coleta de saliva empregando tubos falcon e solução para bochecho com sacarose a 5%, com posterior armazenamento em freezer a -20°C para rastreamento do HPV e genotipagem para o sorotipo 16 e 18 por PCR convencional. Na amostra predominou a presença do sexo masculino 59 de 90 (65,6%), com idade média de 38,8 anos, variando entre 18 e 69 anos, renda familiar média de 1,95 Salários Mínimos (DP = 1,37). A prevalência de HPV nesta amostra foi de 23 de 90 (25,6%) e dos sorotipos 16 e 18 foi 8 de 90 (8,9%). A co-infecção por HPV é comumente observada em pacientes portadores de HIV. / To identify the presence of high-risk serotypes human papillomavirus (HPV) in patients with sexually transmitted infections (STIs). A sample of 90 patients were from two referral hospitals in treatment of STIs. An interview was conducted to identify the sample’s profile a saliva collections being perfomed using falcon tubs and mount rinse with 5% sucrose, subsequente storage in a freezer at -20ºC for HPV screening and genotyping for serotype 16 and 18 by conventional PCR. In the sample predominant male presence 59 of 90 (65.6%) with mean age of 38.8 years, ranging between 18 and 69 years, average family income of 1.95 minimum wages (SD = 1, 37). The prevalence of HPV in this sample was 23 of 90 (25.6%) and the serotype HPV 16 and 18 was 8 of 90 (8.9%). Co-infection with HPV is commonly observed in HIV patients.
14

Occurrence of high risk human papillomaviruses and cervical cancer among fertile-aged women in Finland

Laukkanen, P. (Päivi) 04 December 2012 (has links)
Abstract High risk human papilloma virus (hrHPV) infection is a necessary but not a sufficient cause of cervical cancer. In Finland, since 1990 the incidence of cervical cancer has increased among women younger than 40 years of age despite a nationwide screening programme. In this thesis, the overall objective is to address the role of possible, earlier hrHPV epidemic in this increased incidence of cervical cancer. The target population includes all fertile-aged women in Finland during 1983–2006. The actual study population comprised all women with a minimum of two pregnancies within five years and under 32 years of age in 1983–1997 and under 29 years of age in 1995–2003 identified from the Finnish Maternity Cohort (FMC). From this subpopulation, two subcohorts were selected for hrHPV antibody analysis by random sampling stratified by age and calendar time. All cases of cervical cancer diagnosed for women under 50 years of age during 1983–2002 and 1986–2006 were identified from the Finnish Cancer Registry. The case-cohort design, used for estimating population attributable fractions (PAF) associated with hrHPV, included the cases of cervical cancer and the first subcohort of FMC. A steady annual increase of 0.7% per year in the incidence of HPV16 was estimated to have taken place in Finland from 1983 to 1997 among the 23–31-year-old women with at least two pregnancies. The estimated seroprevalence of HPV16 increased from 17% to 24%, respectively. The PAF of hrHPV exposures in squamous cell carcinoma of the uterine cervix (SCC) was estimated as 73% (95% CI: 13% to 93%). For 26–31-year-old women born in the 1960s and 1970s the incidence of SCC was roughly double compared with women born in the late 1950s. Mathematical modelling indicated that changes in the sexual behaviour partly accounted for the increase seen in the incidence of cervical cancer in the 1990s. The findings of this thesis indicate that growth in the background exposure to HPV16 preceded the increase of incidence of cervical cancer in Finland. At younger birth cohorts, the increase of the incidence of SCC is visible among fertile-aged women in Finland. Whether overall screening starting at 25 years of age, higher participation rate for cervical screening or HPV vaccination of early adolescents is the future solution to lowering the incidence of cervical cancer among young women remains to be seen. / Tiivistelmä Ihmisen papilloomaviruksen (HPV), erityisesti korkean riskin tyypin (hrHPV), aiheuttama infektio on kohdunkaulan syövän välttämätön, mutta ei riittävä syytekijä. Suomessa vuoden 1990 jälkeen kohdunkaulan syövän ilmaantuvuus on valtakunnallisesta seulonnasta huolimatta noussut alle 40-vuotiailla naisilla. Tämän väitöskirjan tavoitteena on osoittaa, mikä rooli mahdollisella aiemmalla hrHPV-epidemialla on kyseiseen kohdunkaulan syövän ilmaantuvuuden kasvuun. Tutkimuksen kohdeväestöön kuuluvat kaikki lisääntymisikäiset suomalaiset naiset. Varsinainen tutkimusväestö koostui kaikista vuosina 1983–97 alle 32-vuotiaana ja vuosina 1995–2003 alle 29-vuotiaana kaksi kertaa raskaana olleista naisista, jotka identifioitiin Suomen äitikohortista (FMC). Tästä joukosta valittiin satunnaisotannalla kaksi alikohorttia hrHPV-laboratorioanalyysejä varten. Kaikki vuosina 1983–2002 ja 1986–2006 kohdunkaulan syöpädiagnoosin alle 50-vuotiaana saaneet naiset poimittiin Suomen syöpärekisteristä. Tapaus-kohorttiasetelma, jota käytettiin hrHPV altistukseen liittyvien väestösyyosuuksien (PAF) estimoinnissa, sisälsi kohdunkaulan syöpätapaukset ja ensimmäisen alikohortin. Suomalaisten 23–31 -vuotiaiden, vähintään kahdesti raskaana olleiden, naisten vuosittainen HPV16-ilmaantuvuus kasvoi tasaisesti 0.7&#160;% per vuosi ajanjaksolla 1983–1997. Vastaavasti HPV16:n vallitsevuus kasvoi 17 prosentista 24 prosenttiin. Kohdunkaulan levyepiteelisyövän hrHPV-altistukseen liittyvän PAF:n estimoitiin olevan 73&#160;% (95&#160;%:n luottamusväli 13–93&#160;%). Levyepiteelisyövän ilmaantuvuus oli suunnilleen kaksinkertainen 1960- ja 1970-luvulla syntyneillä naisilla, heidän ollessaan 26–31 -vuotiaita, verrattuna 1950-luvulla syntyneisiin samanikäisiin naisiin. Matemaattisen mallinnuksen tulosten perusteella kohdunkaulan syövän ilmaantuvuuden nousu 1990- luvulla selittyy ainakin osittain sukupuolikäyttäytymisen muutoksilla. Tämän väitöskirjan tulokset osoittavat, että kasvanut HPV16-virukselle altistuminen edelsi kohdunkaulan syövän ilmaantuvuuden nousua Suomessa. Levyepiteelisyövän ilmaantuvuuden nousu nuorimmissa syntymäkohorteissa on nähtävissä lisääntymisikäisillä naisilla Suomessa. Tulevaisuudessa nähdään, onko seulonnan aloittaminen 25-vuotiaana, korkeampi seulontaan osallistumisosuus vai nuorten aikuisten HPV-rokottaminen ratkaisu nuorten naisten kohdunkaulan syövän ilmaantuvuuden vähentämiseksi.
15

Carcinoma epidermoide da via aerodigestória alta em pacientes com idade inferior a 40 anos: análise clínica e molecular / Squamous Cell Carcinoma of the Head and Neck in patients under 40 years: clinical and molecular analysis

Santos, Alexandre Bezerra dos 30 August 2013 (has links)
O carcinoma epidermoide da região da cabeça e pescoço (CECP) é uma doença de alta prevalência, no Brasil e no mundo, e com grande impacto na qualidade de vida dos pacientes. Mais frequentemente, ocorre em pacientes ao redor da sexta década de vida, com longo histórico de tabagismo e etilismo. Nota-se, porém, um importante aumento na sua incidência em uma população mais jovem, em geral sem histórico de exposição duradoura aos fatores de risco clássicos, o que nos faz questionar se não se trata de uma doença de características distintas. Os objetivos deste estudo foram avaliar aspectos demográficos, clínicos e anatomopatológicos de pacientes com CECP em uma faixa etária inferior a 40 anos, comparando-os com pacientes de maior idade, especialmente em relação à sobrevida, exposição a fatores de risco, expressão de marcadores biológicos em amostras tumorais e não tumorais (margens livres de doença), bem como a presença do Papilomavirus Humano (HPV). Realizou-se estudo transversal de pacientes com carcinomas de cavidade oral (exceto lábio), orofaringe, laringe e hipofaringe, prospectivamente incluídos em um banco de tumores de CECP no período de 2002 a 2010 pelo grupo de pesquisa GENCAPO. Foram coletados dados demográficos, clínicos e patológicos para ambos os grupos de doentes, e realizou-se uma análise por pareamento em relação aos marcadores imunoistoquímicos p53, Ki-67, EGFR, VEGF e p16, em amostras tumorais e de mucosas normais. As análises de sobrevida global e livre de doença, bem como as comparações entre o tabagismo e o etilismo foram feitas com a população total da amostra. A incidência de tabagismo foi menor nos pacientes <40 anos (p=0,048), mas não a de etilismo (p=0,079), no entanto a carga tabágica foi menor entre os pacientes jovens (p<0,0001), bem como a carga etílica (p=0,012). As quantificações de imunoexpressão dos marcadores em amostras tumorais não foram diferentes entre os grupos para p53 (p=0,535), Ki-67 (p=0,669), EGFR (p=0,074), VEGF (p=0,423) e p16 (p=0,125). A análise de amostras não tumorais não mostrou diferença para os marcadores p53(p=0,570), EGFR (p=0,945) e VEGF (p=0,700). A expressão de Ki-67 foi menor em pacientes <40 anos (p=0,021). O HPV tipo 16 foi positivo em um caso de orofaringe em uma paciente (entre cinco) <40 anos, e em nenhum caso de cavidade oral e de laringe. O HPV tipo 18 foi negativo em todos os casos, de ambos os grupos. Na análise de sobrevida, foi observado que a sobrevida global de toda a coorte não mostrou diferença entre os grupos (p=0,754), mesmo se estratificarmos para cavidade oral (p=0,825), laringe (p=0,769) e orofaringe (p=0,891). A sobrevida livre de doença também não foi diferente entre os grupos (p=0,408), mesmo em se estratificando para cavidade oral (p=0,473), laringe (p=0,736) e orofaringe (p=0,510) em cinco anos. No entanto, a sobrevida livre de doença foi menor em pacientes <40 anos no primeiro ano (p=0,042). Na análise univariada, o estádio avançado e o etilismo foram associados a maior risco de morte para todos os sítios (p=0,010) e, na análise multivariada, além do estádio avançado (p=0,013), o etilismo foi fator de maior risco de morte para os casos de câncer de Laringe (p=0,024). Assim, concluímos que o CECP em pacientes com idade <40 anos não foi diferente, em relação às características anatomopatológicas testadas, e à imunomarcação para p53, Ki-67, EGFR, VEGF e p16 em relação aos CECPs em pacientes >=40 anos. O tabagismo e o etilismo foram menos intensos entre os pacientes <40 anos, e a positividade para o HPV foi muito baixa para todos os pacientes. A Sobrevida Global foi semelhante entre os grupos, embora o paciente <40 anos tenha apresentado maior índice de recidivas precoces / Head and Neck Squamous Cell Carcinoma (HNSCC) is a major health problem, in Brazil and around the World, due to its prevalence and impact in the quality of life of these patients. It usually occurs in the 6th and 7th, with an intensive exposure to the tobacco and alcohol. However, an increasing number of patients under 40 years is being affected by these tumors, which raises the hypothesis of different features of the disease in younger patients. The objectives of this study were to test if demographic, clinical and pathological aspects of patients with HNSCC vary according to the age, by comparing them with older patients in terms of survival, alcohol and tobacco exposure, HPV positivity through polymerase chain reaction (PCR), and biomarkers in tumor and non-tumoral samples of the aerodigestive tract. We conducted a cross-sectional study of patients with oral cavity (lips excluded), oropharynx, hypopharynx and larynx prospectively included in a multi-institutional HNSCC tumor bank - GENCAPO, from February 2002 to March 2010.Demographic, clinical and pathological data were analyzed. Using matched-pair analysis, we compared young and older patients in relation to immunohistochemical stainig of p53, Ki-67, EGFR, VEGF and p16 biomarkers in tumor and non-tumoral samples. Survival analyses, as well as exposition to tobacco and alcohol use, were performed taking into account the entire cohort. The incidence of tobacco use was lower in the young group (p=0,048), but not for alcohol use (p=0,079), and young patients had a lower lifelong cumulative exposure to tobacco (p<0,0001) and to alcohol (p=0,012). We found no differences in the stainig of tumoral samples for p53 (p=0,535), Ki-67 (p=0,669), EGFR (p=0,074), VEGF (p=0,423) and p16 (p=0,125). The analysis of the non tumoral samples was not different for p53 (p=0,570), EGFR (p=0,945) and VEGF (p=0,700). Expression of Ki-67 was lower in the young group (p=0,021). Analysis of p16 in non tumoral sites was not performed. HPV type-16 was positive in one case (in five) of oropharynx tumor, and in none of the cases of oral cavity and larynx. HPV type-18 was negative in all cases. In the Survival Analysis, the global survival among groups was not different for the entire cohort (p=0,754), and considering the cases of oral cavity (p=0,825), larynx (p=0,769) and oropharynx (p=0,891). The Free-disease Interval in five years was also not different for the entire cohort (p=0,408), and in cases of oral cavity (p=0,473), larynx (p=0,736) and oropharynx (p=0,510). Nevertheless, the Free-disease survival in one year was lower in the young group (p=0,042, in the entire cohort. In the univariated analysis, the late clinical stage was associated a risk for death in all of the sites (p=0,010). In the multivariated analysis, the late clinical stage was associated to higher risk for death (p=0,013) and, in the cases of tumors of larynx, the alcohol consume was associated to a higher risk for death (p=0,024). We conclude that the HNSCC in patients younger than 40 years was not different, in terms of histopathological aspects, immunoexpression for p53, Ki-67, EGFR, VEGF and p16, when compared with older patients. The tobacco and alcohol use was not so important among young patients, and the positivity for HPV was extremely low in both groups. The Overall Survive was similar among groups, although younger patients had a higher rate of early recurrence
16

Study of SUMOylation in HPV-positive human cervical carcinoma HeLa by comparative proteomics and biarsenical-tetracysteine fluorescent labeling system.

January 2007 (has links)
Chan, Ho Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 263-283). / Abstracts in English and Chinese. / Examination Committee List --- p.i / Acknowledgements --- p.ii / Abstract --- p.iv / 摘要 --- p.vi / Table of Contents --- p.viii / List of Abbreviations --- p.xvii / List of Figures --- p.xx / List of Tables --- p.xxv / Chapter Chapter I --- Introduction --- p.1 / Chapter 1.1 --- SUMO (Small Ubiquitin-like Modifier) and SUMOylation --- p.1 / Chapter 1.1.1 --- "Ubiquitin, Ubiquitin-like proteins and SUMO isoforms" --- p.2 / Chapter 1.1.2 --- SUMO cycle --- p.5 / Chapter 1.1.2.1 --- SUMO conjugation consensus sequence --- p.5 / Chapter 1.1.2.2 --- SUMO maturation --- p.6 / Chapter 1.1.2.3 --- SUMO conjugation cascade --- p.7 / Chapter 1.1.2.4 --- SUMO deconjugation --- p.9 / Chapter 1.1.3 --- Mode of SUMO action --- p.12 / Chapter 1.1.4 --- Biological functions of SUMO --- p.13 / Chapter 1.1.4.1 --- SUMO in cancer --- p.14 / Chapter 1.2 --- Human cervical cancer and human papillomavirus (HPV) --- p.17 / Chapter 1.2.1 --- Infectious cycle of HPV-16 --- p.18 / Chapter 1.2.1.1 --- Viral entry --- p.18 / Chapter 1.2.1.2 --- Maintenance --- p.18 / Chapter 1.2.1.3 --- Deregulation of cell cycle --- p.19 / Chapter 1.2.1.4 --- Amplification and virion release --- p.20 / Chapter 1.2.2 --- Viral cancer induction --- p.22 / Chapter 1.2.2.1 --- Integration into the host genome --- p.22 / Chapter 1.2.2.2 --- Viral oncoproteins E6 and E7 --- p.23 / Chapter 1.2.3 --- SUMOylation and HPV --- p.24 / Chapter 1.2.3.1 --- Known examples of virus-host SUMOylation system interaction --- p.24 / Chapter 1.2.3.2 --- Other possible mode of virus-SUMO interaction --- p.26 / Chapter 1.3 --- A novel labeling method: biarsenical-tetracysteine labeling in SUMO study --- p.28 / Chapter 1.3.1 --- Potential use of 2As-4Cys system in SUMO studies --- p.31 / Chapter 1.3.2 --- Potential use of 2As-4Cys system in SUMO proteomics --- p.31 / Chapter 1.4 --- Objectives of the present study --- p.34 / Chapter Chapter II --- Proteomics investigation of SUMOylation in human cervical carcinoma cell line HeLa --- p.35 / INTRODUCTION --- p.35 / Chapter 2.1 --- MATERIALS --- p.37 / Chapter 2.1.1 --- Vectors for expression of SUMO and SUMOylation enzymes in E. coli --- p.37 / Chapter 2.1.2 --- E.coli cell strains --- p.38 / Chapter 2.1.3 --- Mammalian cell lines --- p.39 / Chapter 2.1.4 --- E.coli growth mediums --- p.40 / Chapter 2.1.5 --- Mammalian cell growth medium --- p.41 / Chapter 2.1.6 --- Reagents and buffers --- p.41 / Chapter 2.1.6.1 --- Reagents and buffers for molecular cloning --- p.41 / Chapter 2.1.6.2 --- Reagents and buffers for E.coli protein expression --- p.43 / Chapter 2.1.6.3 --- Reagents and buffers for mammalian cell culture --- p.44 / Chapter 2.1.6.4 --- Reagents and buffers for Western blot study --- p.45 / Chapter 2.1.7 --- Reagents and solutions for two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) sample preparation --- p.46 / Chapter 2.1.7.1 --- Reagents and solutions for 2-DE --- p.46 / Chapter i. --- 2-DE sample preparation --- p.46 / Chapter ii. --- First dimensional gel electrophoresis -isoelectric focusing (IEF) --- p.46 / Chapter iii. --- Second dimensional gel electrophoresis -SDS-PAGE --- p.47 / Chapter iv. --- Silver staining --- p.47 / Chapter 2.1.7.2 --- Reagents and solutions for mass spectrometry sample preparation --- p.48 / Chapter i. --- Destaining of silver stained gel spots --- p.48 / Chapter ii. --- Trypsin digestion --- p.48 / Chapter iii. --- Peptide extraction --- p.48 / Chapter iv. --- Desalting and concentration of peptide mixture --- p.49 / Chapter 2.2 --- METHODS --- p.50 / Chapter 2.2.1 --- Molecular cloning of SUMO-1 into pET-28m and pHM6 vectors --- p.50 / Chapter 2.2.1.1 --- Design of primers for the cloning of SUMO-1 --- p.50 / Chapter 2.2.1.2 --- DNA amplification by polymerase chain reaction (PCR) --- p.51 / Chapter 2.2.1.3 --- DNA extraction from agarose gels --- p.52 / Chapter 2.2.1.4 --- Restriction digestion of vectors and purified PCR products --- p.54 / Chapter 2.2.1.5 --- Ligation of SUMO cDNA into expression vector pET-28m and pHM6 --- p.55 / Chapter 2.2.1.6 --- Preparation of competent cells --- p.56 / Chapter 2.2.1.7 --- Transformation of ligated mixture into competent DH5a --- p.56 / Chapter 2.2.1.8 --- Preparation of plasmid DNA --- p.57 / Chapter 2.2.1.8.1 --- Mini-preparation of plasmid DNA --- p.57 / Chapter 2.2.1.8.2 --- Midi-preparation of plasmid DNA --- p.58 / Chapter 2.2.1.8.3 --- DNA quantification and quality measurement --- p.60 / Chapter 2.2.2 --- "Expression of His6-tagged SUMO, ubc9, TDG, GST-tagged El and MBP-tagged Prdx 1 with E.coli" --- p.60 / Chapter 2.2.3 --- "Purification of His6-tagged SUMO, ubc9, TDG, GST-tagged El and MBP-tagged Prdx 1" --- p.62 / Chapter 2.2.3.1 --- Affinity chromatography --- p.65 / Chapter 2.2.3.1.1 --- Ni-NTA affinity chromatography --- p.65 / Chapter 2.2.3.1.2 --- Heparin affinity chromatography --- p.66 / Chapter 2.2.3.1.3 --- Glutathione affinity chromatography --- p.66 / Chapter 2.2.3.1.4 --- Amylose affinity chromatography --- p.67 / Chapter 2.2.3.2 --- Ion exchange chromatography --- p.68 / Chapter 2.2.3.2.1 --- Anion exchange chromatography --- p.68 / Chapter 2.2.3.2.2 --- Cation exchange chromatography --- p.68 / Chapter 2.2.3.3 --- Size exclusion chromatography --- p.69 / Chapter 2.2.3.4 --- Purification strategies --- p.70 / Chapter 2.2.3.4.1 --- Purification of His6-tagged SUMO --- p.70 / Chapter 2.2.3.4.2 --- Purification of His6-tagged TDG --- p.71 / Chapter 2.2.3.4.3 --- Purification of His6-tagged ubc9 --- p.72 / Chapter 2.2.3.4.4 --- Purification of GST-tagged El --- p.73 / Chapter 2.2.3.4.5 --- Purification of MBP-tagged Prdx 1 --- p.74 / Chapter 2.2.4 --- HeLa and C-33A cell culturing and protein extraction --- p.75 / Chapter 2.2.4.1 --- HeLa and C-33A cell culturing --- p.75 / Chapter 2.2.4.2 --- Protein extraction for in vitro SUMOylation assay --- p.76 / Chapter 2.2.5 --- Protein quantification with Bradford assay --- p.76 / Chapter 2.2.6 --- In vitro SUMO conjugation assay --- p.77 / Chapter 2.2.6.1 --- In vitro SUMO conjugation system optimization --- p.77 / Chapter 2.2.6.2 --- In vitro SUMO conjugation of HeLa cell extract --- p.78 / Chapter 2.2.7 --- Transient transfection of pHM6-SUMO-l into HeLa cells and protein extraction from HeLa cells --- p.79 / Chapter 2.2.7.1 --- Transfection with lipofection method --- p.79 / Chapter 2.2.7.2 --- Determination of transfection efficiency --- p.80 / Chapter 2.2.7.3 --- Whole cell protein extraction of transfected cells --- p.81 / Chapter 2.2.8 --- Protein quantification with BCA assay --- p.81 / Chapter 2.2.9 --- SDS-polyacrylamide gel electrophoresis (SDS-PAGE) --- p.83 / Chapter 2.2.10 --- Western blot analysis --- p.84 / Chapter 2.2.10.1 --- Electro-transfer blotting --- p.84 / Chapter 2.2.10.2 --- Immunoblotting with antibodies --- p.84 / Chapter 2.2.10.3 --- ECL detection --- p.85 / Chapter 2.2.10.4 --- Mild stripping for re-probing --- p.86 / Chapter 2.2.11 --- Two-dimensional gel electrophoresis (2-DE) --- p.86 / Chapter 2.2.11.1 --- Sample preparation --- p.86 / Chapter 2.2.11.2 --- First dimension gel electrophoresis -isoelectric focusing (IEF) --- p.87 / Chapter 2.2.11.3 --- Second dimension gel electrophoresis -SDS-PAGE --- p.88 / Chapter 2.2.11.3.1 --- Strip equilibration --- p.88 / Chapter 2.2.11.3.2 --- 16 x 18cm SDS-PAGE --- p.88 / Chapter 2.2.11.4 --- Visualization of proteins on SDS-polyacrylamide gel --- p.90 / Chapter 2.2.11.4.1 --- Silver staining --- p.90 / Chapter 2.2.11.4.2 --- Coomassie Blue® R250 staining --- p.91 / Chapter 2.2.12 --- Sample preparation for mass spectrometry analysis --- p.92 / Chapter 2.2.12.1 --- Destaining and trypsin digestion --- p.92 / Chapter 2.2.12.2 --- Extraction of peptide mixture --- p.93 / Chapter 2.2.12.3 --- Desalting and concentration of peptide mixture --- p.93 / Chapter 2.3 --- RESULTS --- p.95 / Chapter 2.3.1 --- Construction of recombinant pET-28m-SUMO-l and pHM6-SUMO-l --- p.95 / Chapter 2.3.2 --- "Purification of His6-tagged SUMO, ubc9, TDG and GST-tagged El" --- p.98 / Chapter 2.3.2.1 --- Purification of His6-SUMO --- p.98 / Chapter 2.3.2.2 --- Purification of His6-TDG --- p.101 / Chapter 2.3.2.3 --- Purification of His6-ubc9 --- p.104 / Chapter 2.3.2.4 --- Purification of GST-El --- p.106 / Chapter 2.3.3 --- In vitro SUMO conjugation assay --- p.108 / Chapter 2.3.3.1 --- Optimization of in vitro SUMO conjugation system --- p.108 / Chapter 2.3.3.2 --- In vitro SUMO conjugation of HeLa cell protein extract --- p.111 / Chapter 2.3.3.2.1 --- Protein extraction for in vitro sumoylation assay --- p.111 / Chapter 2.3.3.2.2 --- In vitro SUMOylation of HeLa cell lysate --- p.114 / Chapter 2.3.4 --- Differential proteomes of control and in vitro SUMOylated HeLa total cellular extract --- p.116 / Chapter 2.3.4.1 --- Mass spectrometric identification of differential protein candidates --- p.123 / Chapter 2.3.5 --- Overexpression of SUMO-1 in HeLa cells by transient transfection --- p.127 / Chapter 2.3.6 --- Differential proteomes of total cellular protein extract from control and SUMO-1 transfected HeLa cells --- p.128 / Chapter 2.3.6.1 --- Mass spectrometric identification of differential protein candidates --- p.132 / Chapter 2.4 --- Proteins identified in proteomic study with in vitro SUMOylation -Analysis of protein candidate --- p.133 / Chapter 2.4.1 --- Proteins identified from the in vitro investigation --- p.133 / Chapter 2.4.2 --- Verification of putative SUMO substrate Prdx 1 --- p.139 / Chapter 2.4.2.1 --- Purification of Prdx 1 --- p.139 / Chapter 2.4.2.2 --- In vitro SUMOylation of Prdx 1 --- p.142 / Chapter 2.4.3 --- Highlights of the proteins identified --- p.145 / Chapter 2.4.3.1 --- DJ-1 protein --- p.145 / Chapter 2.4.3.2 --- nm23A --- p.145 / Chapter 2.4.3.3 --- v-crk protein of CT10 --- p.146 / Chapter 2.4.3.4 --- Annexin I --- p.146 / Chapter 2.4.3.5 --- "Enolase 1, aldolase A, triosephosphate isomerase (TIM) and phosphoglycerate mutase 1" --- p.147 / Chapter 2.4.3.6 --- CyclophilinA(CypA) --- p.148 / Chapter 2.4.3.7 --- Stress induced phosphoprotein 1 (Stip 1) --- p.148 / Chapter 2.4.3.8 --- TSA and peroxiredoxin 1 (Prdx 1) --- p.149 / Chapter 2.5 --- Proteins identified in proteomic study with overexpression of SUMO-1 in HeLa cells -Analysis of protein candidate --- p.150 / Chapter 2.5.1 --- Proteins identified from the in vivo investigation --- p.150 / Chapter 2.5.2 --- Verification of upregulation of keratin 17 --- p.157 / Chapter 2.5.2.1 --- Immunoblotting against keratin 17 --- p.157 / Chapter 2.5.3 --- Highlights of the proteins identified --- p.159 / Chapter 2.5.3.1 --- "Heat shock proteins (Hsp 60, 70 and 27)" --- p.159 / Chapter 2.5.3.2 --- 14-3-3σ protein (SFN protein) --- p.161 / Chapter 2.5.3.3 --- PDZ-RGS3 --- p.162 / Chapter 2.5.3.4 --- "Keratins 8, 17" --- p.163 / Chapter 2.5.3.5 --- XIAP-1 --- p.164 / Chapter 2.5.3.6 --- ISG15 --- p.164 / Chapter 2.6 --- DISCUSSION --- p.166 / Chapter Chapter III --- Characterization of a novel fluorescent labeling method: Biarsencial-tetracysteine labeling in SUMO study --- p.182 / INTRODUCTION --- p.182 / Chapter 3.1 --- MATERIALS --- p.184 / Chapter 3.1.1 --- "Molecular cloning, protein expression and purification of pET-28m-4Cys 1 -SUMO-1 and pET-28m-4Cys2-SUMO-1" --- p.184 / Chapter 3.1.2 --- Mammalian cell culture and transient transfection of pHM6-4Cysl-SUMO-1 and pHM6-4Cys2-SUMO-l into HeLa cells --- p.184 / Chapter 3.1.3 --- Reagents and buffers --- p.184 / Chapter 3.1.3.1 --- Reagents and buffers for Lumio´ёØ in-gel labeling --- p.184 / Chapter 3.1.3.2 --- Reagents and buffers for Lumio´ёØ in cell labeling --- p.185 / Chapter 3.1.3.3 --- Reagents and buffers for immunostaining --- p.186 / Chapter 3.2 --- METHODS --- p.187 / Chapter 3.2.1 --- Molecular cloning of tetracysteine-tagged SUMO (4Cys-SUMO) into pET-28m and pHM6 vectors --- p.187 / Chapter 3.2.1.1 --- Design of primers and oligonucleotides encoding tetracysteine tag --- p.187 / Chapter 3.2.1.1.1 --- For 4Cysl-SUMO-1 --- p.187 / Chapter 3.2.1.1.2 --- For 4Cys2-SUMO-l --- p.188 / Chapter 3.2.1.2 --- DNA amplification of 4Cysl-SUMO-1 by Polymerase chain reaction (PCR) --- p.189 / Chapter 3.2.1.3 --- Restriction digestion of vectors and purified PCR products of 4Cysl-SUMO-1 --- p.191 / Chapter 3.2.1.4 --- Ligation of 4Cysl-SUMO into expression vector pET-28m and pHM6 --- p.191 / Chapter 3.2.1.5 --- Restriction digestion of pET-28m-SUMO and pHM6-SUMO for ligation with 4Cys2 oligos --- p.192 / Chapter 3.2.1.6 --- Ligation of 4Cys2 oligos to the digested pET-28m-SUMO and pHM6-SUMO plasmids --- p.193 / Chapter 3.2.1.6.1 --- Self-annealing of the 4Cys oligonucleotides --- p.193 / Chapter 3.2.1.6.2 --- Phosphorylation of ds 4Cys2 oligos and ligation to the plasmids --- p.193 / Chapter 3.2.2 --- Expression and purification of pET-28m-4Cys 1 -SUMO-1 and pET-28m-4Cys2-SUMO-1 in E.coli expression system --- p.195 / Chapter 3.2.3 --- Immunohistochemistry (IHC) staining of endogenous SUMO in HeLa cells --- p.196 / Chapter 3.2.4 --- In-cell labeling of 4Cysl/2-SUMO with Lumio´ёØ Reagent --- p.197 / Chapter 3.2.4.1 --- Preparation --- p.197 / Chapter 3.2.4.2 --- In-cell Lumio´ёØ labeling --- p.198 / Chapter 3.2.4.3 --- Detection and imaging of the labeled cells --- p.199 / Chapter 3.2.5 --- In-gel labeling of 4Cysl/2-SUMO with Lumio´ёØ Reagent --- p.199 / Chapter 3.2.5.1 --- Lumio´ёØ in-gel labeling --- p.199 / Chapter 3.2.5.2 --- Visualization and imaging of the labeled gel --- p.200 / Chapter a. --- UV illumination at 302 nm --- p.200 / Chapter b. --- Typhoon Trio TMLaser-scanning at 532 nm --- p.201 / Chapter 3.2.5.3 --- Detection limit of fluorescent 4Cys2-SUMO-l in SDS-PAGE --- p.201 / Chapter 3.2.5.4 --- In-gel labelling in two-dimensional electrophoresis (2-DE) --- p.202 / Chapter 3.2.5.4.1 --- Modification of equilibration buffer before SDS-PAGE --- p.202 / Chapter 3.3 --- RESULTS --- p.203 / Chapter 3.3.1 --- Adoption of old version of 4Cys-tag (4Cys 1) in SUMO study --- p.203 / Chapter 3.3.1.1 --- Construction of recombinant pET-28m-4Cys 1 -SUMO-1 and pHM6-4Cysl-SUMO-1 --- p.203 / Chapter 3.3.1.2 --- In vivo HA-4Cysl-SUMO-1 Lumio´ёØ labelling --- p.205 / Chapter 3.3.1.3 --- Immunohistochemistry (IHC) staining of endogenous SUMO in HeLa cells --- p.207 / Chapter 3.3.1.4 --- Expression and purification of His6-4Cysl-SUMO-1 --- p.208 / Chapter 3.3.1.5 --- Validation of 4Cys1-SUMO-1 conjugate by Lumio´ёØ in-gel labeling --- p.211 / Chapter 3.3.2 --- Adoption of a modified version of 4Cys-tag (4Cys2) in SUMO study --- p.213 / Chapter 3.3.2.1 --- Construction of recombinant pET-28m-4Cys2-SUMO-l and pHM6-4Cys2-SUMO-l --- p.213 / Chapter 3.3.2.2 --- In vivo HA-4Cys2-SUMO-l Lumio´ёØ labelling --- p.216 / Chapter 3.3.2.3 --- Expression and purification of His6-4Cys2-SUMO-1 --- p.219 / Chapter 3.3.2.4 --- Validation of 4Cys2-SUMO-l conjugate Lumio´ёØ in-gel labeling --- p.221 / Chapter 3.3.3 --- 2As-4Cys labeling in two-dimensional electrophoresis (2-DE) --- p.223 / Chapter 3.3.3.1 --- Detection limit of 4Cys2-SUMO-l in SDS-PAGE --- p.224 / Chapter 3.3.3.2 --- Lumio´ёØ labeling in 2-DE --- p.226 / Chapter 3.4 --- DISCUSSION --- p.232 / Chapter Chapter IV --- Conclusion and Future Perspectives --- p.242 / Chapter 4.1 --- Conclusion on proteomic study of SUMOylation --- p.242 / Chapter 4.2 --- Future perspectives of proteomic study of SUMOylation --- p.245 / Chapter 4.2.1 --- In vitro study --- p.245 / Chapter 4.2.2 --- In vivo study --- p.246 / Chapter 4.3 --- Conclusion of the investigation of biarsencial-tetracysteine (2As-4Cys) system application on SUMO study --- p.247 / Chapter 4.4 --- Future perspectives of the application of 2As-4Cys system application on SUMO study --- p.249 / Chapter 4.4.1 --- In cell study --- p.249 / Chapter 4.4.2 --- In gel study --- p.250 / Appendices --- p.251 / Chapter 1. --- Genotype of E.coli strains --- p.251 / Chapter 2. --- Vector maps --- p.252 / Chapter a. --- Vector map and MCS of pET-28a --- p.252 / Chapter b. --- Vector map and MCS of pHM6 --- p.253 / Chapter c. --- Vector information of pTwo-E --- p.254 / Chapter 3. --- Primers used in this study --- p.255 / Chapter 4. --- Nikon TE2000 filter sets spectrums --- p.257 / Chapter a. --- FITC/GFP filter set --- p.257 / Chapter b. --- RFP filter set --- p.257 / Chapter c. --- UV/DAPI/Hoechst filter set --- p.258 / Chapter 5. --- Akt signalling pathway diagram --- p.259 / Chapter 6. --- DNA sequence of SUMOs and 4Cys2 oligonucleotide --- p.260 / Chapter 7. --- Electrophoresis markers --- p.261 / References --- p.263
17

Análise do impacto das proteínas E6/E7 de diferentes variantes moleculares de HPV-16 sobre as vias de transdução de sinal mediadas por MAPK / Analysis of the impact of E6/E7 proteins of different molecular variants of HPV-16 upon MAPK signaling pathways

Hochmann Valls, Jimena Paola 07 July 2016 (has links)
A infecção persistente por HPV-16 está fortemente associada ao risco de desenvolvimento de neoplasias do colo do útero, vagina, vulva, pênis, canal anal e orofaringe. O estudo detalhado da variabilidade nucleotídica intra-típica de HPV-16 resultou em importantes achados no que concerne à filogenia e evolução viral, e à história natural das infecções. Variantes Asiático-Americanas (AA) e E-350G de HPV-16 foram associadas com maior risco de persistência da infecção viral e desenvolvimento de câncer de colo de útero quando comparadas à variante Européia protótipo (E-P ou E-350T), embora esta ainda apresente alto risco quando comparada aos outros tipos virais. Mais recentemente, diferenças funcionais entre as proteínas E6/E7 das distintas variantes moleculares de HPV- 16 estão sendo descritas, a fim de explicar as diferenças nas associações epidemiológicas observadas. Dados do nosso grupo apontaram para a transcrição aumentada do gene MEK2 especificamente em queratinócitos humanos primários (PHKs) transduzidos com E6/E7 da variante E-350G. Pelo exposto, objetivou-se: (1) Analisar os níveis de ativação de proteínas efetoras das vias de transdução de sinal mediadas por MAPK e PI3K/AKT em queratinócitos imortalizados por E6/E7 de três variantes moleculares de HPV-16 (AA, E-P, E-350G); (2) Analisar os efeitos das proteínas E6/E7 dessas variantes sob as vias de MAPK quanto à indução de fatores de transcrição; (3) Analisar o potencial transformante de PHKs imortalizados pelas diferentes variantes, e em cooperação com a proteína celular c-MYC; (4) Analisar o potencial de migração e invasão em PHKs imortalizados pelas diferentes variantes de HPV-16, e em cooperação com a proteína celular c-MYC. Neste estudo observou-se que a variante AA de HPV-16 induziu a maior ativação das vias de sinalização estudadas (MAPK, e PI3K/AKT). Ademais, PHKs imortalizados por esta variante apresentaram maior capacidade de migração, de invasão através de uma matriz de colágeno, além de maior potencial transformante. Adicionalmente, as células imortalizadas pela variante AA apresentaram maior expressão da proteína mesenquimal vimentina e diminuição dos níveis da proteína epitelial E-caderina, sugerindo ativação parcial de Transição Epitélio Mesênquima (EMT) nestes queratinócitos. Ademais, quando o oncogene c-MYC foi co-transduzido nas diferentes linhagens infectadas por E6/E7 de HPV-16, foi observado que em PHKs imortalizados pela variante AA também houve maior ativação da via de MAPK-ERK, maior migração, e um potencial transformante semelhante, em relação às células co-transduzidas pela variante E-350G e c-MYC. Em conjunto, estes dados sugerem que a variante AA de HPV-16 possui vantagem seletiva sob as outras variantes em promover transformação celular, migração e invasão, e isto poderia explicar, ao menos em parte, a maior prevalência desta variante no câncer cervical. Os resultados gerados neste estudo são de extrema relevância para avaliar o impacto da variabilidade intra-típica de HPV-16 sobre o potencial oncogênico observado em estudos epidemiológicos / Persistent infection with HPV-16 is strongly associated with risk of developing neoplasia in the uterine cervix, vagina, vulva, penis, anal canal and oropharynx. The detailed study of HPV-16 intra-typical nucleotide variability resulted in important findings regarding phylogeny and viral evolution, and the natural history of infections. Asian-American (AA) and E-350G variants of HPV-16 were associated with increased risk of persistent viral infection and development of cervical cancer compared to the European prototype (E-P or E-350T), although this variant still presents higher risk when compared to other viral types. More recently, functional differences between the E6/E7 proteins of distinct molecular variants of HPV-16 are being described, in order to explain the differences in the epidemiological associations observed. Data from our group pointed to increased transcription of the MEK2 gene specifically in primary human keratinocytes (PHKs) transducing E6/E7 of the E-350G variant. Consequently, the aims of this study were: 1) To examine the activation levels of effector proteins of the signal transduction pathways mediated by MAPK and PI3K/AKT in PHKs immortalized by E6/E7 of three different molecular variants of HPV-16 (AA, E-P, E-350G); (2) To analyze the effects of E6/E7 of different molecular variants of HPV-16 upon MAPK pathways concerning the induction of transcription factors; (3) To analyze the transforming potential of PHKs immortalized by different molecular variants of HPV-16, and in cooperation with the cellular protein c- MYC; (4) To analyze the potential of migration and invasion in PHKs immortalized by different molecular variants of HPV-16, and in cooperation with the cellular protein c- MYC. In this study we observed that the AA variant of HPV-16 induced higher activation of both signaling pathways studied (MAPK, and PI3K/AKT). Furthermore, this variant presented increased migration capacity, higher invasion through a collagen matrix, and greater transforming potential. Moreover, cells immortalized by the AA variant showed higher expression of the mesenchymal protein vimentin and a decrease of the epithelial protein E-cadherin, suggesting partial activation of Epithelial Mesenchymal Transition (EMT). In addition, when the c-MYC oncogene was co-transduced in the different cells lines infected with HPV-16 E6/E7, we observed that in PHKs immortalized by the AA variant there was also an enhanced activation of the MAPK-ERK pathway, a higher ability to migrate, and similar transformation potential in comparison with cells co-transduced with the E-350G variant and c-MYC. Taken together, this data suggest that the AA molecular variant of the HPV-16 has a selective advantage over the other variants to promote cell transformation, migration and invasion, and this could partly explain the higher prevalence of this variant in cervical cancer. The results generated in this study are very important to assess the impact of intra-typical variability of HPV-16 on the oncogenic potential observed in epidemiological studies
18

High-risk human papilloma virus (HPV) and survival in patients with esophageal carcinoma : a pilot study

Dreilich, Martin, Bergqvist, Michael, Moberg, Martin, Brattström, Daniel, Gustavsson, Inger, Bergström, Stefan, Wanders, Alkwin, Hesselius, Patrik, Wagenius, Gunnar, Gyllensten, Ulf January 2006 (has links)
BACKGROUND: Human papilloma virus (HPV) in patients with esophageal carcinoma has previously been studied with an average detection rate of 15%, but the role of HPV in relation to survival is less clear. In cervical cancer, lung cancer and tonsil cancer HPV viral load is a predictive factor for survival and outcome of treatment. The primary aim was to study the spectrum of high-risk HPV types in esophageal tumors. Secondary, as a pilot study we investigated the association between HPV status and the survival rates. METHODS: We compared both the presence and the viral load of high-risk HPV types 16, 18, 31, 33, 39, 45, 52, 58, and 67 in relation to clinical data from patients with esophageal carcinoma. Survival data and tumor samples were retrieved from 100 patients receiving treatment at the Department of Oncology, Uppsala Hospital, Uppsala, Sweden. The tumor samples were investigated for HPV viral load using real-time PCR. RESULTS: HPV 16 was detected in 16% of the patients; no other HPV type was detected. HPV 16 infection had no significant effect on survival (p = 0.72). Also, HPV 16 did not improve survival after treatment (radiotherapy or chemotherapy). CONCLUSION: Only HPV 16 was detected among the patients. HPV 16 in esophageal carcinoma patients did not influence survival or improve therapy response. However, given the size of the study there is a need to examine a larger cohort in order to understand in more detail the effect of high risk HPV types in esophageal carcinoma. / <p>De två första författarna delar förstaförfattarskapet.</p>
19

Análise do impacto das proteínas E6/E7 de diferentes variantes moleculares de HPV-16 sobre as vias de transdução de sinal mediadas por MAPK / Analysis of the impact of E6/E7 proteins of different molecular variants of HPV-16 upon MAPK signaling pathways

Jimena Paola Hochmann Valls 07 July 2016 (has links)
A infecção persistente por HPV-16 está fortemente associada ao risco de desenvolvimento de neoplasias do colo do útero, vagina, vulva, pênis, canal anal e orofaringe. O estudo detalhado da variabilidade nucleotídica intra-típica de HPV-16 resultou em importantes achados no que concerne à filogenia e evolução viral, e à história natural das infecções. Variantes Asiático-Americanas (AA) e E-350G de HPV-16 foram associadas com maior risco de persistência da infecção viral e desenvolvimento de câncer de colo de útero quando comparadas à variante Européia protótipo (E-P ou E-350T), embora esta ainda apresente alto risco quando comparada aos outros tipos virais. Mais recentemente, diferenças funcionais entre as proteínas E6/E7 das distintas variantes moleculares de HPV- 16 estão sendo descritas, a fim de explicar as diferenças nas associações epidemiológicas observadas. Dados do nosso grupo apontaram para a transcrição aumentada do gene MEK2 especificamente em queratinócitos humanos primários (PHKs) transduzidos com E6/E7 da variante E-350G. Pelo exposto, objetivou-se: (1) Analisar os níveis de ativação de proteínas efetoras das vias de transdução de sinal mediadas por MAPK e PI3K/AKT em queratinócitos imortalizados por E6/E7 de três variantes moleculares de HPV-16 (AA, E-P, E-350G); (2) Analisar os efeitos das proteínas E6/E7 dessas variantes sob as vias de MAPK quanto à indução de fatores de transcrição; (3) Analisar o potencial transformante de PHKs imortalizados pelas diferentes variantes, e em cooperação com a proteína celular c-MYC; (4) Analisar o potencial de migração e invasão em PHKs imortalizados pelas diferentes variantes de HPV-16, e em cooperação com a proteína celular c-MYC. Neste estudo observou-se que a variante AA de HPV-16 induziu a maior ativação das vias de sinalização estudadas (MAPK, e PI3K/AKT). Ademais, PHKs imortalizados por esta variante apresentaram maior capacidade de migração, de invasão através de uma matriz de colágeno, além de maior potencial transformante. Adicionalmente, as células imortalizadas pela variante AA apresentaram maior expressão da proteína mesenquimal vimentina e diminuição dos níveis da proteína epitelial E-caderina, sugerindo ativação parcial de Transição Epitélio Mesênquima (EMT) nestes queratinócitos. Ademais, quando o oncogene c-MYC foi co-transduzido nas diferentes linhagens infectadas por E6/E7 de HPV-16, foi observado que em PHKs imortalizados pela variante AA também houve maior ativação da via de MAPK-ERK, maior migração, e um potencial transformante semelhante, em relação às células co-transduzidas pela variante E-350G e c-MYC. Em conjunto, estes dados sugerem que a variante AA de HPV-16 possui vantagem seletiva sob as outras variantes em promover transformação celular, migração e invasão, e isto poderia explicar, ao menos em parte, a maior prevalência desta variante no câncer cervical. Os resultados gerados neste estudo são de extrema relevância para avaliar o impacto da variabilidade intra-típica de HPV-16 sobre o potencial oncogênico observado em estudos epidemiológicos / Persistent infection with HPV-16 is strongly associated with risk of developing neoplasia in the uterine cervix, vagina, vulva, penis, anal canal and oropharynx. The detailed study of HPV-16 intra-typical nucleotide variability resulted in important findings regarding phylogeny and viral evolution, and the natural history of infections. Asian-American (AA) and E-350G variants of HPV-16 were associated with increased risk of persistent viral infection and development of cervical cancer compared to the European prototype (E-P or E-350T), although this variant still presents higher risk when compared to other viral types. More recently, functional differences between the E6/E7 proteins of distinct molecular variants of HPV-16 are being described, in order to explain the differences in the epidemiological associations observed. Data from our group pointed to increased transcription of the MEK2 gene specifically in primary human keratinocytes (PHKs) transducing E6/E7 of the E-350G variant. Consequently, the aims of this study were: 1) To examine the activation levels of effector proteins of the signal transduction pathways mediated by MAPK and PI3K/AKT in PHKs immortalized by E6/E7 of three different molecular variants of HPV-16 (AA, E-P, E-350G); (2) To analyze the effects of E6/E7 of different molecular variants of HPV-16 upon MAPK pathways concerning the induction of transcription factors; (3) To analyze the transforming potential of PHKs immortalized by different molecular variants of HPV-16, and in cooperation with the cellular protein c- MYC; (4) To analyze the potential of migration and invasion in PHKs immortalized by different molecular variants of HPV-16, and in cooperation with the cellular protein c- MYC. In this study we observed that the AA variant of HPV-16 induced higher activation of both signaling pathways studied (MAPK, and PI3K/AKT). Furthermore, this variant presented increased migration capacity, higher invasion through a collagen matrix, and greater transforming potential. Moreover, cells immortalized by the AA variant showed higher expression of the mesenchymal protein vimentin and a decrease of the epithelial protein E-cadherin, suggesting partial activation of Epithelial Mesenchymal Transition (EMT). In addition, when the c-MYC oncogene was co-transduced in the different cells lines infected with HPV-16 E6/E7, we observed that in PHKs immortalized by the AA variant there was also an enhanced activation of the MAPK-ERK pathway, a higher ability to migrate, and similar transformation potential in comparison with cells co-transduced with the E-350G variant and c-MYC. Taken together, this data suggest that the AA molecular variant of the HPV-16 has a selective advantage over the other variants to promote cell transformation, migration and invasion, and this could partly explain the higher prevalence of this variant in cervical cancer. The results generated in this study are very important to assess the impact of intra-typical variability of HPV-16 on the oncogenic potential observed in epidemiological studies
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Carcinoma epidermoide da via aerodigestória alta em pacientes com idade inferior a 40 anos: análise clínica e molecular / Squamous Cell Carcinoma of the Head and Neck in patients under 40 years: clinical and molecular analysis

Alexandre Bezerra dos Santos 30 August 2013 (has links)
O carcinoma epidermoide da região da cabeça e pescoço (CECP) é uma doença de alta prevalência, no Brasil e no mundo, e com grande impacto na qualidade de vida dos pacientes. Mais frequentemente, ocorre em pacientes ao redor da sexta década de vida, com longo histórico de tabagismo e etilismo. Nota-se, porém, um importante aumento na sua incidência em uma população mais jovem, em geral sem histórico de exposição duradoura aos fatores de risco clássicos, o que nos faz questionar se não se trata de uma doença de características distintas. Os objetivos deste estudo foram avaliar aspectos demográficos, clínicos e anatomopatológicos de pacientes com CECP em uma faixa etária inferior a 40 anos, comparando-os com pacientes de maior idade, especialmente em relação à sobrevida, exposição a fatores de risco, expressão de marcadores biológicos em amostras tumorais e não tumorais (margens livres de doença), bem como a presença do Papilomavirus Humano (HPV). Realizou-se estudo transversal de pacientes com carcinomas de cavidade oral (exceto lábio), orofaringe, laringe e hipofaringe, prospectivamente incluídos em um banco de tumores de CECP no período de 2002 a 2010 pelo grupo de pesquisa GENCAPO. Foram coletados dados demográficos, clínicos e patológicos para ambos os grupos de doentes, e realizou-se uma análise por pareamento em relação aos marcadores imunoistoquímicos p53, Ki-67, EGFR, VEGF e p16, em amostras tumorais e de mucosas normais. As análises de sobrevida global e livre de doença, bem como as comparações entre o tabagismo e o etilismo foram feitas com a população total da amostra. A incidência de tabagismo foi menor nos pacientes <40 anos (p=0,048), mas não a de etilismo (p=0,079), no entanto a carga tabágica foi menor entre os pacientes jovens (p<0,0001), bem como a carga etílica (p=0,012). As quantificações de imunoexpressão dos marcadores em amostras tumorais não foram diferentes entre os grupos para p53 (p=0,535), Ki-67 (p=0,669), EGFR (p=0,074), VEGF (p=0,423) e p16 (p=0,125). A análise de amostras não tumorais não mostrou diferença para os marcadores p53(p=0,570), EGFR (p=0,945) e VEGF (p=0,700). A expressão de Ki-67 foi menor em pacientes <40 anos (p=0,021). O HPV tipo 16 foi positivo em um caso de orofaringe em uma paciente (entre cinco) <40 anos, e em nenhum caso de cavidade oral e de laringe. O HPV tipo 18 foi negativo em todos os casos, de ambos os grupos. Na análise de sobrevida, foi observado que a sobrevida global de toda a coorte não mostrou diferença entre os grupos (p=0,754), mesmo se estratificarmos para cavidade oral (p=0,825), laringe (p=0,769) e orofaringe (p=0,891). A sobrevida livre de doença também não foi diferente entre os grupos (p=0,408), mesmo em se estratificando para cavidade oral (p=0,473), laringe (p=0,736) e orofaringe (p=0,510) em cinco anos. No entanto, a sobrevida livre de doença foi menor em pacientes <40 anos no primeiro ano (p=0,042). Na análise univariada, o estádio avançado e o etilismo foram associados a maior risco de morte para todos os sítios (p=0,010) e, na análise multivariada, além do estádio avançado (p=0,013), o etilismo foi fator de maior risco de morte para os casos de câncer de Laringe (p=0,024). Assim, concluímos que o CECP em pacientes com idade <40 anos não foi diferente, em relação às características anatomopatológicas testadas, e à imunomarcação para p53, Ki-67, EGFR, VEGF e p16 em relação aos CECPs em pacientes >=40 anos. O tabagismo e o etilismo foram menos intensos entre os pacientes <40 anos, e a positividade para o HPV foi muito baixa para todos os pacientes. A Sobrevida Global foi semelhante entre os grupos, embora o paciente <40 anos tenha apresentado maior índice de recidivas precoces / Head and Neck Squamous Cell Carcinoma (HNSCC) is a major health problem, in Brazil and around the World, due to its prevalence and impact in the quality of life of these patients. It usually occurs in the 6th and 7th, with an intensive exposure to the tobacco and alcohol. However, an increasing number of patients under 40 years is being affected by these tumors, which raises the hypothesis of different features of the disease in younger patients. The objectives of this study were to test if demographic, clinical and pathological aspects of patients with HNSCC vary according to the age, by comparing them with older patients in terms of survival, alcohol and tobacco exposure, HPV positivity through polymerase chain reaction (PCR), and biomarkers in tumor and non-tumoral samples of the aerodigestive tract. We conducted a cross-sectional study of patients with oral cavity (lips excluded), oropharynx, hypopharynx and larynx prospectively included in a multi-institutional HNSCC tumor bank - GENCAPO, from February 2002 to March 2010.Demographic, clinical and pathological data were analyzed. Using matched-pair analysis, we compared young and older patients in relation to immunohistochemical stainig of p53, Ki-67, EGFR, VEGF and p16 biomarkers in tumor and non-tumoral samples. Survival analyses, as well as exposition to tobacco and alcohol use, were performed taking into account the entire cohort. The incidence of tobacco use was lower in the young group (p=0,048), but not for alcohol use (p=0,079), and young patients had a lower lifelong cumulative exposure to tobacco (p<0,0001) and to alcohol (p=0,012). We found no differences in the stainig of tumoral samples for p53 (p=0,535), Ki-67 (p=0,669), EGFR (p=0,074), VEGF (p=0,423) and p16 (p=0,125). The analysis of the non tumoral samples was not different for p53 (p=0,570), EGFR (p=0,945) and VEGF (p=0,700). Expression of Ki-67 was lower in the young group (p=0,021). Analysis of p16 in non tumoral sites was not performed. HPV type-16 was positive in one case (in five) of oropharynx tumor, and in none of the cases of oral cavity and larynx. HPV type-18 was negative in all cases. In the Survival Analysis, the global survival among groups was not different for the entire cohort (p=0,754), and considering the cases of oral cavity (p=0,825), larynx (p=0,769) and oropharynx (p=0,891). The Free-disease Interval in five years was also not different for the entire cohort (p=0,408), and in cases of oral cavity (p=0,473), larynx (p=0,736) and oropharynx (p=0,510). Nevertheless, the Free-disease survival in one year was lower in the young group (p=0,042, in the entire cohort. In the univariated analysis, the late clinical stage was associated a risk for death in all of the sites (p=0,010). In the multivariated analysis, the late clinical stage was associated to higher risk for death (p=0,013) and, in the cases of tumors of larynx, the alcohol consume was associated to a higher risk for death (p=0,024). We conclude that the HNSCC in patients younger than 40 years was not different, in terms of histopathological aspects, immunoexpression for p53, Ki-67, EGFR, VEGF and p16, when compared with older patients. The tobacco and alcohol use was not so important among young patients, and the positivity for HPV was extremely low in both groups. The Overall Survive was similar among groups, although younger patients had a higher rate of early recurrence

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