Infecção persistente por tipos oncogênicos de papilomavírus humano (HPV) é considerada como o principal fator de risco para desenvolvimento de carcinoma invasivo do colo uterino (CCU) e de lesões intraepiteliais cervicais (SIL). Fatores genéticos do hospedeiro, como o polimorfismos de genes HLA (human leukocyte antigen), também têm sido implicados na suscetibilidade a estas patologias e à infecção por (HPV), como observado em diversos estudos caso-controle. Neste estudo investigou-se em uma coorte de mulheres (Ludwig-McGill cohort) se a variabilidade dos genes HLA-DRB1 e -DQB1 influenciam na história natural das infecções por HPV e no risco de SIL. A tipificação de DRB1 e DQB1 foi realizada em 620 amostras provenientes de um estudo epidemiológico prospectivo. A positividade para HPV foi testada em amostras da mesma paciente coletadas a cada 4 meses, obtidos durante o primeiro ano de seguimento, enquanto os resultados de citologia perfazem os 2 primeiros anos de seguimento. Infecções persistentes de curta ou longa duração foram definidas como 2 e 3 resultados consecutivos positivos para o mesmo tipo de HPV, respectivamente. As associações foram estimadas através de razões de chance e intervalos de confiança de 95%, ajustadas para potenciais fatores de confusão. Os resultados obtidos indicam que a prevalência da infecção por HPV e o risco de persistência variam dependendo do haplótipo HLA. O haplótipo DRB1*0301-DQB1*0201 mostrou-se protetor contra a infecção por HPV, e DRB1*1102-DQB1 *0301 contra infecções persistentes. Já os haplótipos DRB1*1601-DQB1*0502 e DRB1 *0807-DQB1*0402 foram fatores de risco para infecções persistentes por HPV. Não foi observada uma forte concordância entre risco de infecção por HPV e risco de SIL associados a determinado HLA, em parte porque o número de pacientes com SIL foi um fator limitante neste estudo. Um risco aumentado de SIL, independente da infecção por HPV, foi associado com DRB1*0301 e DR12. Portadoras de DR4 e DQB1*0601 tiveram uma maior probabilidade de desenvolver SIL e HSIL, respectivamente. Uma associação negativa entre o alelo DQB1*0301 e HSIL foi verificada. Análise do dimorfismo na posição 86 da cadeia β de HLA-DR mostrou que valina nesta posição tem um efeito protetor para prevalência e persistência de infecção por HPV, e maior risco de SIL no grupo com infecções transitórias por HPV. Em outra análise, investigamos a distribuição de grupos alélicos de DRB1 em uma série independente de amostras provenientes de pacientes com CCU. Observamos um risco diminuído de desenvolvimento de CCU associado a DR3. Por outro lado, DR4 e DR8/12 mostraram-se fatores de risco para o CCU nesta população. Estes resultados sugerem que o polimorfismo de HLA desempenha um papel na história natural das infecções por HPV, SIL e CCU. Também analisamos respostas linfoproliferativas em pacientes com CCU, contra peptídeos derivados de E6 e E7 de HPV16. As respostas positivas foram mais freqüentes contra peptídeos de E6 do que E7. Não observamos resposta contra um peptídeo ou região em particular. Parte desta diversidade nas respostas linfoproliferativas pode ser relacionada com o polimorfismo de genes HLA e seu papel na seleção de epítopos. / Persistent infection with oncogenic human papillomavirus (HPV) is the major risk factor for the development of malignant lesions in the uterine cervix. Host factors have also been implicated in the pathogenesis of these diseases. Associations between human leukocyte antigen (HLA) polymorphisms and cervical cancer, precursor lesions or HPV infections have been reported by case-control studies in several populations. This study investigated through cohort analysis if human leukocyte antigen (HLA)-DRB1 and DQB1 variability is related to human papillomavirus (HPV) infection and squamous intraepithelial lesions (SIL) prevalence and persistence. HLA-DRB1 and DQB1 genes were typed in 620 samples from the Ludwig-McGill cohort. HPV positivity was tested in specimens collected every 4 months during the first year of follow-up. Persistent and long-term infections were defined as at least 2 or 3 consecutive positive results for the same HPV type, respectively. Analysis of SIL included data obtained during the two first years of follow-up. The magnitudes of associations were estimated by unconditional logistic regression analysis adjusted for potential confounders. Certain HLA alleles and haplotypes were associated with HPV either HPV prevalence or persistence. The DRB1*0301-DQB1*0201 haplotype was associated with a lower risk for HPV infection and DRB1*1102-DQB1*0301 for HPV persistence. DRB1*1601-DQB1*0502 and DRB1*0807-DQB1*0402 were associated with a increased risk for persistent HPV infection. It was not observed a strong concordance between the associations verified for HPV prevalence/persistence and SIL, possibly due to the limited number of SIL specimens. A higher risk for SIL, independent of HPV infection, was observed for DRB1*0301 and DR12. DR4 and DQB1*0601 carriers showed a higher frequency of SIL and HSIL, respectively. A negative association between DQB1*0301 and HSIL was verified. Valine at position 86 of the DRβ chain was associated with reduced risks of HPV positivity and persistence, as compared to glycine carriers. However, valine carriers had a higher risk of SIL if transiently infected by HPV. We also analyzed an independent sample of patients with invasive cervical, and a protective effect was observed for DR3. On the other hand, DR4 and DR8/12 were associated with a higher risk for cervical cancer in this population. Our results suggest that HLA class II polymorphisms and pocket 1 profile are involved in clearance and maintenance of HPV infection and the risk of SIL and CCU, consistent with the hypothesis that genetic background is important in the natural history of HPV infections and associated lesions. We also analyzed lymphoproliferative responses against HPV16 E6 and E7 peptides, in patients with invasive cervical cancer. Lymphoproliferative responses were more frequent for E6 peptides than for E7 peptides. The responses were not restricted to a particular peptide, which is expected based on HLA variability observed among patients.

Foi estudado o perfil nosológico da população ribeirinha do Baixo Rio Machado em Rondônia, área de Amazônia Ocidental no Brasil. Neste estudo, escolhemos abordar o perfil das seguintes doenças: malária, hepatite viral B e C, parasitose intestinal e papilomavírus humano. Estas doenças foram priorizadas devido à importância clínica e epidemiológica e também escassez de estudos referentes nas populações ribeirinhas amazônicas. Para isto, foi realizado um estudo descritivo no Baixo Rio Machado que se localiza a 250 km de Porto Velho (capital do Estado de Rondônia) pela margem direita do Rio Madeira, que é um afluente volumoso do Rio Amazonas, no Brasil. Nesta área, vivem aproximadamente 806 pessoas distribuídas em 55 comunidades ribeirinhas isoladas. Em Rondônia, encontramos locais, como o Rio Machado, que abrigam a presença de portadores assintomáticos do Plasmodium, fato que pode contribuir para a persistência desta doença na região. Para caracterizar o perfil da malária ribeirinha, focalizando aspectos da infecção assintomática e sintomática, foram realizados hemoscopia e Reação em Cadeia da Polimerase (PCR) com amplificação do DNA ribossomal do parasita para Plasmodium vivax e Plasmodium falciparum para o diagnóstico da malária. Foi considerado como assintomático o paciente com hemoscopia positiva ou PCR positivo que permaneceu sem sintomas durante pelo menos 60 dias. Foi realizado acompanhamento longitudinal de 70 dias após o primeiro corte transversal (nC1=585 pessoas) para observação dos pacientes assintomáticos diagnosticados por hemoscopia, onde 25 pacientes (4,25%) permaneceram assintomáticos durante todo esse seguimento. Após, foi realizado mais dois cortes transversais a cada 6 meses (nC2=583 pessoas, nC3=607 pessoas), com tratamento dos indivíduos assintomáticos diagnosticados por PCR no corte transversal anterior ou hemoscopia atual e também dos casos sintomáticos. Foi estudado, na população que permaneceu na área durante toda a pesquisa (n=379), o perfil e o impacto do tratamento da infecção assintomática. Houve diminuição da infecção por P. falciparum de seis vezes e aumento da prevalência de malária por P. vivax de aproximadamente três vezes. O diagnóstico por PCR foi de 2-5 vezes mais eficiente do que por hemoscopia e a prevalência de infecção assintomática foi de 16 a 22% nos cortes transversais. Assim, foi observada a importância do tratamento dos indivíduos assintomáticos para o controle da malária no local, sendo que o incremento de malária por Plasmodium vivax deve ter ocorrido devido a recaídas da doença. Com o estudo entomológico da área, foi verificado que o vetor Anopheles possui atividade hematofágica moderada e principalmente em região peridomiciliar, sendo o A. darlingi a principal espécie da região. Existem poucos dados sobre a prevalência de hepatites na população ribeirinha de Rondônia, o que dificulta a vigilância epidemiológica nestas regiões amazônicas. Foi realizado um estudo de prevalência de hepatite B e C na área, com 123 pacientes pertencentes a 5 comunidades ribeirinhas, incluindo todas as pessoas que estavam presentes na área no momento do corte transversal, de todas as faixas etárias. Foi realizada sorologia para os marcadores de hepatite B: HbsAg, Anti-Hbc (total) e Anti-Hbs e sorologia para hepatite C com o marcador anti-HCV. Foram encontrados 12 (14,7%) pacientes com hepatite B aguda, 29 (38,7%) pacientes apresentaram imunidade vacinal para hepatite B e 7 (9,3%) pacientes apresentaram hepatite C, sendo que um (1,3%) paciente tinha co-infecção para hepatite B e C. Notou-se que esta população ribeirinha está exposta às hepatites virais, sendo necessário intensificar a vigilância epidemiológica na área, assim como a cobertura vacinal e também fornecer cuidados preventivos, curativos e paliativos em relação a estas doenças. A infecção pelo papilomavírus humano (HPV) é altamente prevalente, sendo detectada em aproximadamente 10% a 20% da população sexualmente ativa entre 15 e 49 anos de idade. A introdução de testes mais acurados para a detecção do DNA do HPV em investigações epidemiológicas confirmou a importância do HPV, principalmente dos tipos de alto risco, como o principal fator de risco para o desenvolvimento de neoplasia intra-epitelial cervical e câncer do colo uterino. Não foram encontrados estudos sobre a existência do HPV em populações ribeirinhas amazônicas na literatura médica. Foi realizado, então, um estudo transversal para levantar a prevalência de HPV nesta população, com 84 participantes em idade sexualmente ativa presentes na área. Após coleta de consentimento informado e questionário clínico-epidemiológico, foi realizado exame para isolar o HPV. A tipagem do HPV foi realizada com amplificação dos DNAs por PCR empregando iniciadores genéricos seguida de hibridização em pontos, capaz de identificar mais de 40 tipos diferentes de HPVs. Foram encontradas 18 pacientes contaminadas pelo HPV, perfazendo 21,4% da amostra. Os tipos de HPV encontrados foram: 53, 58, 31, 56, 16, 83, 55, 66, 45, 51, 40, 42, 6, 68. Os tipos de HPV mais freqüentes foram 51 (23%), 58 (19%), 53 (7,7%), 83 (7,7%), sendo HPV 16 encontrado em 3,8% das pacientes HPV positivas e a prevalência do HPV de alto risco oncogênco foi de 13,1%. Desta forma, foi encontrado alta prevalência de HPV na população ribeirinha amazônica estudada, evidenciando a necessidade de vigilância epidemiológica para câncer de colo uterino na região. Por fim, foi estabelecido a prevalência de parasitoses intestinais na população, abordando a correlação das enteroparasitoses com malária assintomática e anemia, realizando um inquérito coproparasitológico na área incluindo pacientes de todas as faixas etárias, que estivessem dispostos a participar do estudo. A análise das amostras foi realizada pelo método da Sedimentação Espontânea (método de Lutz ou Hoffmann, Pons & Janer). Entre os 268 exames de fezes realizados, a prevalência de parasitose intestinal encontrada na região em estudo foi de 86,6%. Entre os helmintos, Ascaris lumbricoides (47%), Ancilostomideos (37,3%), Trichuris trichiura (3,4%), Capillaria hepatica (2,3%), foram os parasitas mais encontrados. Entre os protozoários foram encontrados: Entamoeba coli (21,4%), Entamoeba histolytica (12%), Giardia intestinalis (15,4%), Endolimax nana (10,1%) e Iodamoeba butschlii (7,5%). A alta prevalência de parasitose intestinal encontrada na pesquisa foi concordante com outros dados desenvolvidos na Região Amazônica. Com este estudo, a região da Amazônia Ocidental insere-se no cenário geográfico mundial de distribuição da Capillaria hepatica, particularmente, a região do Baixo Rio Machado. / Was studied the nosological profile of the riverside population of the Baixo Rio Machado in Rondônia, Western Amazon area of Brazil. In this study, was chosed the profile of following diseases: malaria, hepatitis B and C, intestinal parasite and human papillomavirus. These diseases have been prioritized due to clinical and epidemiological importance and scarcity of studies in the riverside Amazon population. For this, was conducted a descriptive study in the Baixo Rio Machado which is located 250 km from Porto Velho (capital of Rondônia State) in the right bank of the Rio Madeira which is a large tributary of the Amazon River in Brazil. In this area, live about 806 people distributed in 55 riversides communities isolated. In Rondônia, we find places such as the Rio Machado, which shelter to the presence of asymptomatic carriers of Plasmodium, which may contribute to the persistence of this disease in the region. To characterize the profile of malaria riverside, focusing on aspects of symptomatic and asymptomatic infections, were performed haemoscopia and Polymerase Chain Reaction (PCR) with amplification of ribosomal DNA for the parasite Plasmodium vivax and Plasmodium falciparum to the diagnosis of malaria. Was considered as asymptomatic patient with positive haemoscopia or positive or PCR that remained without symptoms for at least 60 days. Longitudinal follow-up was conducted for 70 days after the first cross section (nC1 = 585 people) for observation of asymptomatic patients diagnosed by haemoscopia where 25 patients (4.25%) remained asymptomatic throughout the follow-up. After was performed two cross cuts every 6 months (nC2 = 583 people, nC3 = 607 people), with treatment of asymptomatic individuals diagnosed by PCR in previous transverse cross-sections or haemoscopia a current and also symptomatic cases. We studied in the population that remained in the area throughout the study (no= 379), the profile and impact of treatment of asymptomatic infection. There was a decrease in infection by P. falciparum of six times and increased prevalence of malaria by P. vivax approximately three times. The diagnosis by PCR was 2-5 times more efficient than haemoscopia and the prevalence of asymptomatic infection was 16 to 22% in transverse cross-sections. Thus, was saw the importance of treatment of asymptomatic individuals for the control of malaria in the place, and the increase in malaria by Plasmodium vivax should have occurred due to relapse of the disease. With entomological study of the area, was saw that the vector Anopheles has moderate blood activity and especially in peridomiciliary region and the A. darlingi the main species in the region. There are few data on the prevalence of hepatitis in riverside population of Rondônia, which makes surveillance in Amazonian regions. Was conducted a study of prevalence of hepatitis B and C in the area, with 123 patients belonging to 5 communities, including all the people who were present in the area at the cross section of all ages. Serology was performed for markers of hepatitis B: HBsAg, anti-HBc (total) and anti-HBs and serology for hepatitis C with anti-HCV marker. Was found 12 (14.7%) patients with acute hepatitis B, 29(38.7%) patients demonstrated immunity to hepatitis B vaccine and 7(9.3%) patients had hepatitis C, with one (1.3%) patient had co-infection for hepatitis B and C. Realize that this riverside population is exposed to viral hepatitis, being necessary to intensify epidemiological surveillance in the area, as well as immunization coverage and provide preventive care, curative and palliative for these diseases. The infection by human papillomavirus (HPV) is highly prevalent, being detected in approximately 10% to 20% of the sexually active population between 15 and 49 years of age. The introduction of more accurate tests for the detection of HPV DNA in epidemiological investigations confirmed the importance of HPV, particularly types of high risk, as the main risk factor for the development of cervical intraepithelial neoplasia and cervical cancer. Was found no studies on the existence of HPV in riverside Amazonian populations in the medical literature. The transversal cross-section study was take up to raise the prevalence of HPV in this population, with 84 participants in sexually active age in the area. After collection of informed consent and clinical-epidemiological questionnaire, was conducted to isolate the HPV test. The typing of HPV was taking with the DNAs for PCR using generic primers followed by hybridization in points, able to identify over 40 different types of HPV. Was found 18 patients infected by HPV, comprising 21.4% of the sample. The HPV types found were: 53, 58, 31, 56, 16, 83, 55, 66, 45, 51, 40, 42, 6, 68. The most common HPV types were 51 (23%), 58 (19%), 53 (7.7%), 83 (7.7%) with HPV 16 found in 3.8% of HPV positive patients and prevalence the high risk HPV oncogenic was 13.1%. Thus, was find high prevalence of HPV in riverside Amazonian population studied, highlighting the need for surveillance for cancer of the cervix in the region. Finally, was established the prevalence of intestinal parasites in the population, deal the correlation of intestinal with asymptomatic malaria and anemia, taking the fecal examination conducting in the area including patients of all ages, who were willing to participate in the study. The analysis of samples was performed by the spontaneous sedimentation method (method of Lutz or Hoffmann, Pons & Janer). Among the 268 fecal examinations, the prevalence of intestinal parasite found in the region under study was 86.6%. Among helminths, Ascaris lumbricoides (47%), Ancilostomideos (37.3%), Trichuris trichiura (3.4%), Capillaria hepatica (2.3%) were found more parasites. Among the protozoa were: Entamoeba coli (21.4%), Entamoeba histolytica (12%), Giardia intestinalis (15.4%), Endolimax nana (10.1%) and Iodamoeba butschlii (7.5%).The high prevalence of intestinal parasite found in the survey was consistent with other data developed in the Amazon region. In this study, the region of the Western Amazon is part of the scenario of global geographic distribution of Capillaria hepatica, particularly the region of the Baixo Rio Machado.

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

À l'heure actuelle, une large proportion des recherches vouées à l'identification et au développement de nouvelles thérapies anticancéreuses est basée sur l'apoptose. Dans les dernières décennies, divers composés phytochimiques ont été caractérisés comme des agents pharmacologiques susceptibles d'éliminer les cellules cancéreuses via l'induction de l'apoptose. Parmi ceux-ci, l'isoliquiritigénine (ILG), un flavonoïde naturellement présent dans les racines de réglisse, se distingue des autres par ses nombreuses propriétés thérapeutiques incluant une activité antitumorale. Chez les mammifères, les cellules apoptotiques (CA) peuvent être complètement dégradées via leur capture par des cellules phagocytaires spécialisées ou servir de vecteurs d'ADN dans un processus appelé transfert horizontal de gènes (THG). Ainsi, il a été mis en évidence que des CA dérivées de cancer du col de l'utérus peuvent induire le transfert de séquences d'oncogènes de papillomavirus humains (HPV) à des fibroblastes primaires humains (HPFs) qui acquièrent des propriétés de cellules transformées. Cependant, les mécanismes cellulaires et moléculaires impliqués dans l'internalisation de CA par les fibroblastes, un modèle de phagocyte non-professionnel, n'ont pas encore été clairement identifiés et la caractérisation de ces événements qui précèdent le THG est essentielle à la compréhension de ce processus et de la transformation des cellules receveuses qui peut en découler.Dans ce contexte, les objectifs de cette thèse étaient, (i) d'analyser les effets anticancéreux de l'ILG sur des cellules dérivées de cancer du col de l'utérus, (ii) de caractériser les mécanismes cellulaires et moléculaires impliqués dans la capture des CA par les HPFs, (iii) d'étudier les événements cellulaires qui font suite à ce processus comme la maturation des phagosomes, le THG et l'acquisition de propriétés de transformation et enfin, (iv) de démontrer la preuve de la conservation de la capacité tumorigénique des CA in vivo.Un premier travail a permis de mettre en lumière les propriétés antitumorales de l'ILG via une multiplicité d'actions sur des modèles cellulaires de cancer du col de l'utérus in vitro, incluant des activités anti-proliférative, pro-apoptotique, anti-migratoire. Concernant la lignée cellulaire Ca Ski, p53 sauvage et représentative du carcinome du col utérin le plus fréquent, associé à une infection transformante par HPV16, l'apoptose induite par l'ILG semble dépendante de p53 et de la mitochondrie, mais aussi de la voie des récepteurs de mort, comme attesté par l'augmentation des niveaux de protéines p53 et p21, la dissipation du potentiel membranaire mitochondrial, la libération du cytochrome c et le clivage des caspases-9, -8 et -3. Ces effets pourraient être la conséquence de la diminution de l'expression de l'oncoprotéine virale E6 d'HPV16 induite par l'ILG entraînant la restauration de l'expression de p53. Nos travaux révèlent un fort potentiel de l'ILG contre différents types de cellules malignes et ouvrent le champ à de nouvelles modalités de traitement des cancers associés à HPV. / Most of the research strategies aiming at improving anticancer therapies currently target apoptosis. Over the last decades, several natural products derived from herbal medicine or food have been identified as pharmacological agents for cancer cell elimination through apoptosis induction. Among them, isoliquiritigenin (ILG) is a chalcone derivative isolated from liquorice and shallots which exhibits a wide variety of biological functions including antitumor properties.In mammals, apoptotic cells (AC) can either be eliminated after their capture by specialized phagocytes or act as vectors of DNA in a process named horizontal gene transfer (HGT). For instance, AC derived from cervical cancer cells can transfer human papillomavirus (HPV) oncogene sequences to human primary fibroblasts (HPFs) which subsequently acquire transformed cell properties. The molecular mechanisms underlying AC uptake by HPFs, a model of non-professional phagocytes, have not been clearly identified. Characterizing these upstream events appears critical to broaden our understanding of HGT and the ultimate transformation of recipient cells which may subsequently occur.The aims of this work were to (i) study the antitumor effects of ILG on cervical cancer cell lines,(ii) characterize the cellular and molecular mechanisms underlying AC uptake by HPF, (iii) study the cellular events which occur in HPFs following AC engulfment such as phagosome maturation, HGT and acquisition of transformed properties, and (iv) evaluate the tumorigenic properties of AC in vivo.In a first part of this PhD project, we found that ILG exhibits multiple antitumor actions on cervical cancer cells in vitro including anti-proliferative, pro-apoptotic and anti-migration properties. Further studies on apoptosis-related events were conducted in Ca Ski cells (p53wt, HPV16 DNA positive), which are representative of the most frequent cervical carcinoma. The treatment of Ca Ski cells with ILG is associated with increased levels of p53 and p21 proteins, loss of mitochondrial membrane potential, cytochrome c release and caspase-9, -8 and -3 cleavage. These features suggest that ILG-induced apoptosis is dependent on p53 and involve both mitochondrial and death receptor- mediated pathways. The effect of ILG in Ca Ski cells may be partly explained by the decrease of HPV16 E6 oncoprotein expression and the associated raise of p53 levels observed after cell treatment. Our work highlights the potential of ILG as an antitumor agent and provides the opportunity of new treatment. ln the second part of this work, we set up a method based on flow cytometry to quantitatively analyze AC uptake. This original method and microscopy analysis allowed us to show that HPFs act as non-professional phagocytes and are able to engulf subcellular fragments rather than dying whole cells, with lower efficiency and rapidity compared to professional phagocytes as macrophages. Uptake of AC by HPFs depends on time, temperature and the presence of bivalent ions. Morphological analysis and fonctional assays using endocytosis inhibitors revealed a mechanism related to phagocytosis and/or macropinocytosis. The recognition of phosphatidylserine exposed on the surface of AC by their receptor BAIl has emerged as a required event for AC uptake by HPFs.

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

INTRODUÇÃO: O papilomavírus humano (HPV) encontra-se amplamente distribuído na população mundial. Apesar da grande maioria das infecções serem transientes, assintomáticas e passíveis de regressão espontânea, a infecção persistente por tipos de alto risco de HPV é necessária para o desenvolvimento de neoplasias intraepiteliais cervicais. Uma vez que apenas uma pequena parcela das infecções progride à lesões malignas após um longo período desde o diagnóstico inicial de lesões precursoras, tem-se iniciado a busca por fatores que possam influenciar na progressão ou na eliminação destas manifestações iniciais. A variabilidade genética viral tem sido apontada como um dos fatores que interagem neste processo. Embora virtualmente todos os tumores da cérvice uterina apresentem o DNA viral, neoplasias em outros sítios anatômicos têm sido apenas em parte correlacionadas com a presença viral, sendo o HPV proposto como um dos agentes causadores de tumores em sítios de cabeça e pecoço. MÉTODOS: Espécimens clínicos de tumores de cabeça e pescoço, fixados em formalina e contidos em parafina (FFPE), provenientes do Instituto do Câncer do Estado de São Paulo (n=79) e da Santa Casa de Misericórida de São Paulo (n=94), tiveram seu DNA extraído, seguido de diagnóstico e genotipagem de HPV pela metodologia de Inno-LiPA. Análises de linhagens moleculares foram realizadas nas amostras HPV-16 positivas. Análise imunohistoquímica de P16INK4a foi realizada em todas as amostras. RESULTADOS: A presença do DNA viral foi encontrada em 24,1% (19/79) dentre a série de tumores provenientes do ICESP, sendo a cavidade oral o sítio em que foi observada a maior proporção de DNA viral (27,1%), enquanto que 13,8% (13/94) dentre os espécimens provenientes da Santa Casa apresentaram-se positivos para HPV, sendo a cavidade oral o sítio em que foi observada a maior proporção do DNA viral (18,1%). O HPV-16 foi o tipo mais prevalente, detectado em 73,4% das amostras HPV positivas provenientes do ICESP e 61,5% das amostras provenientes da Santa Casa. Independente da Instituição, as amostras foram alocadas no clado das linhagens Asiático-Americana e Europeia em 50%, cada uma, entre os 18 tumores HPV-16 positivos em que as análises de linhagem foram possíveis. Não foi observada, nestas séries, correlação entre a superexpressão de P16INK4a e a presença do DNA viral. CONCLUSÃO: Nas amostras analisadas, o DNA de HPV foi detectado em 18,5% dos 173 espécimens. O HPV-16 foi o tipo mais prevalente. Isolados da linhagem Europeia e da linhagem Asiatico-Americano foram detectados em 50% dos casos, cada uma, dentre as amostras HPV-16 analisadas por este estudo / INTRODUCTION: Human papillomaviruses (HPV) are widely distributed worldwide. Although the majority of infections are usually transient, asymptomatic and frequently regress spontaneously, persistent infections by high-risk HPVs are necessary for the development of cervical intraepithelial neoplasia. Once only a small proportion of infections progress to malignant lesions after a long period of time since the initial diagnosis of precursor lesions, the search for factors that might influence the progression or clearence of these early manifestations are currently under way. Viral genetic variability has been proposed as one of the factors interacting in this process. Although virtually all cervix tumors present the viral DNA, neoplasias from other anatomical sites have been only in part correlated with viral presence, and HPV has been proposed as one causative agent in tumors from head and neck sites. METHODS: Clinical specimens of formalin-fixed paraffin embedded head and neck tumors, provided by the Cancer Institute of São Paulo (n=79) and also by the Santa Casa de Misericórdia de São Paulo (n=94), were submitted to DNA extraction and further HPV diagnostic and genotyping by the Inno-LiPA methodology. Molecular lineages analyses were performed in all HPV-16 positive samples. P16INK4a immunohistochemical analyses were conducted in all samples. RESULTS: HPV DNA was detected among 24.1% (19/79) of samples provided by ICESP, tumors from oral cavity presented the highest viral positivity (27.1%), whereas 13,8% (13/94) of the samples from Santa Casa presented HPV DNA, tumors from the oral cavity also presented the highest HPV positivity with 18.1% of viral DNA presence. HPV-16 was the most prevalent type detected in 73.4% and 61.5% of HPV positive ICESP and Santa Casa samples, respectively. Irrespective of the Institution, samples submitted to lineage analyzes were allocated in the Asiatic-American and European phylogenetic branches in 50%, each one, among the 18 tumors HPV-16 positive for which lineage analysis was possible. No correlation between P16INK4a overexpression and HPV DNA presence was observed. CONCLUSION: In this study, HPV DNA was detected in 18.5% among 173 head and neck tumor specimens. HPV-16 was the most prevalent type. The European and the Asiatic-American lineage were detected in 50% of the cases, each one, among the cases HPV-16 positive analyzed

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

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>

Our understanding of humoral immune response to human papillomavirus (HPV) infection has been mainly derived from studies in women. Very little is known about humoral immune response to HPV in men. There is also a growing interest in understanding the burden of HPV exposure in the subgroups of the male population, including men who have sex with women (MSW), men who have sex with men (MSM) and men who have sex with both men and women (MSMW). This dissertation was undertaken to understand and characterize humoral immune response, measured by detectable serum antibody IgG, to HPV 6, 11, 16 and 18 infection, to estimates seroprevalence of HPV 6, 11, 16 and 18, to determine the associations of sociodemographic and sexual behavioral factors with seroprevalence of individual HPV types, and to evaluate the role of serum antibodies in the subsequent acquisition of infection with the same HPV type, genetically related and un-related HPV types. Three studies that compose of this dissertation were conducted within the framework of two longitudinal studies of HPV infection in men: a single-site natural history study of male residents of Tucson, Arizona (the 1st study: N=285); and a multinational natural history study of healthy men residing in São Paulo, Brazil, Cuernavaca, Mexico, and Tampa, Florida (the 2nd study: N=1477; the 3rd study: N=2187). Men were recruited using similar eligibility criteria in both natural history studies and followed every 6 months for a maximum of 18 months in the single-site study and 48 months in the multi-national study. HPV DNA status was assessed using the PGMY09/11 L1 consensus primer system and the Linear Array HPV Genotyping Protocol. Testing of serum antibodies to HPV 6, 11, 16 and 18 was performed with virus-like particle-based ELISA assays. Data from our studies indicate that exposure to HPV 6, 11, 16 and 18, the four HPV types targeted in the currently license HPV vaccines, is common. Of 285 male residents of Tucson, Arizona, 28.8% of them were seropositive to HPV 16 and/or 18 at study entry. Similarly, approximately one third of 1477 participants of the multi-national male HPV natural history study were seropositive to at least one vaccine HPV type, with the percentage of 21.8% in U.S. site, 33.4% in Mexico site, and 49.1% in Brazil site. It is also noted that seroprevalence of individual vaccine HPV types is greatly elevated among men of different sexual practices. Seroprevalence of HPV 6, 11, 16 and/or 18 was twice as high among MSM and MSMW compared to MSW. Likewise, seroprevalence of individual HPV types was two fold or higher among MSW and MSMW. Our findings suggest that the predominant predictors of seropositivity to HPV 6, 11, 16 and 18 are age and same-sex sexual behaviors. Seroprevalence increased with age among young-to-middle-aged men with significant upward age trends observed for HPV 11, 16 and 18. MSM, compared to MSW, more likely to be seropositive to HPV 16 or 18. Similarly, men who practiced same-sex anal sex, compared to those who did not, were significantly more likely to be seropositive to HPV 6, 11, 16 and 18, respectively. Among 276 men free of HPV 16 at enrollment in Tucson, We did not detect statistically significant associations between the baseline serum antibodies to HPV 16 and/or 18 and subsequent risk of infection with homogeneous HPV types or related-HPV types. Of 2187 men residing in three countries who tested HPV 16 negative at enrollment, the risk of subsequent HPV 16 infection was not associated with enrollment HPV 16 serum antibodies status. Our data provide important estimates of population exposure to vaccine HPV types for future studies modeling potential vaccine impact and vaccine cost effectiveness in men. Our findings also support strategic vaccination of males as an effective preventive measure for HPV-related diseases and cancers in men and their sex partners, men and women alike.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 4 uppsatser.