No / Werner's syndrome (WS) is an autosomal recessive genetic disorder caused by loss of function mutation in wrn and is a useful model of premature in vivo ageing. Cellular senescence is a plausible causal mechanism of mammalian ageing and, at the cellular level, WS fibroblasts show premature senescence resulting from a combination of telomeric attrition and replication fork stalling. Over 90% of WS fibroblast cultures achieve < 20 population doublings (PD) in vitro compared to wild type human fibroblast cultures. It has been proposed that some cell types, capable of proliferation, will fail to show a premature senescence phenotype in response to wrn mutations. To test this hypothesis, human dermal keratinocytes (derived from both WS and wild type patients) were cultured long term. WS Keratinocytes showed a replicative lifespan in excess of 100 population doublings but maintained functional growth arrest mechanisms based on p16 and p53. The karyotype of the cells was superficially normal and the cultures retained markers characteristic of keratinocyte holoclones (stem cells) including p63 expression and telomerase activity. Accordingly we conclude that, in contrast to WS fibroblasts, WS keratinocytes do not demonstrate slow growth rates or features of premature senescence. These findings suggest that the epidermis is among the tissue types that do not display symptoms of premature ageing caused by loss of function of wrn. This is in support that Werner's syndrome is a segmental progeroid syndrome.

La métaplasie épithéliale est un phénomène d'adaptation tissulaire apparaissant à la suite d'une agression chronique. Caractérisées par le remplacement d'un épithélium par un autre, ces transformations métaplasiques peuvent apparaître dans différentes régions anatomiques (bronches, sophage, col de l'utérus, estomac et vessie). Bien que mieux adapté à résister à un agent irritatif, l'épithélium métaplasique présente cependant une susceptibilité accrue au développement cancéreux. Ainsi, la grande majorité (87%) des lésions (pré)néoplasiques cervicales se développe au sein du microenvironnement métaplasique de la zone de transformation du col utérin. Les travaux réalisés dans le cadre de cette thèse ont contribué à une meilleure compréhension des mécanismes responsables de la métaplasie épidermoïde cervicale et ont démontré, pour la première fois, une implication du TGF-β1 et de la PGE2 dans limmunodéficience locale observée dans les foyers de métaplasie mature et immature. Ainsi, en réduisant lexpression de E-cadhérine, le TGF-β1 altère indirectement la rétention épithéliale des cellules présentatrices dantigène en empêchant leurs interactions avec les cellules épithéliales. Quant à la PGE2, elle affecte la migration et le phénotype de ces cellules immunitaires, les rendant tolérogènes et, par conséquent, incapables dactiver les lymphocytes T naïfs. Par ailleurs, il est possible que la réduction de ΔNp63 par les facteurs de transcription Snail et Slug participe à la mise en place des épithélia métaplasiques ainsi quà leur transformation maligne.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The p63 protein is expressed in the nuclei of the mammary myoepithelial cells and has synergisms or antagonisms with p53 tumor suppressor protein. The immunohistochemistry expression of p63 was studied for access the role of myoepithelial cells in histogenesis of the mixed tumors. Additionally, the possible association between p63 and p53 for access the biological aspects of this tumors was evaluated. Four specimens of the normal gland, 20 benign mixed tumors, 35 carcinomas in mixed tumors and 11 tubulopapilary carcinomas were evaluated. Myoepithelial cells forming layers periductals/periacinars continuous were reactive for protein p63 in normal gland and in benign mixed tumor. The carcinomas in mixed tumors and 72.7% (8/11) tubulopapilary carcinomas were reactive for p63. In the mixed tumors star and spindle shaped cells were reactive for p63. The p53 protein was expressed in 20.0% (4/20), 28.6% (10/35) and 36.7% (4/11), benign mixed tumors, carcinoma in mixed tumors and tubulopapilary carcinomas, respectively. There was not relation between p63 and p53 expression in none type of tumor. The present study point the participation of the mioepithelial cells in the histogenesis of the mixed tumors. The decrease in p63 expression in the basal myoepithelial cells of the carcinomas may be important for tumoral progression. / A proteína p63 é expressa no núcleo das células mioepiteliais da mama e apresenta funções sinérgicas ou antagonistas com a proteína de supressão tumoral p53. A expressão imuno-histoquímica de p63 foi estudada para acessar o papel das células mioepiteliais na histogênese dos tumores mistos. Adicionalmente, avaliou-se a possível relação entre expressão imuno-histoquímica de p63 e p53 com a finalidade de obter informações sobre a biologia desses tumores. Quatro amostras de mama normais, 20 tumores mistos benignos, 35 carcinomas em tumores mistos e 11 carcinomas tubulopapilares foram avaliados. Células mioepiteliais, formando camadas periductais/periacinares contínuas, foram imunoreativas para p63 na mama normal e nos tumores mistos benignos. Todos os carcinomas em tumores mistos e 72,7% (8/11) dos carcinomas tubulopapilares foram reativos para p63. A reatividade para p63 foi superior nos tumores mistos benignos quando comparada com os carcinomas. Nos tumores mistos, células mioepiteliais com formato fusiforme e estrelado, presentes no estroma mucinoso também foram reativas para p63. A proteína p53 foi expressa em 20,0% (4/20), 28,6% (10/35) e 36,4% (4/11) dos tumores mistos benignos, carcinomas em tumores mistos e carcinomas tubulopapilares, respectivamente. Não houve relação entre a expressão de p53 e p63 nos diferentes tipos tumorais. O presente estudo evidenciou a participação das células mioepiteliais na histogênese dos tumores mistos. A diminuição da expressão de p63 nas células mioepiteliais que compõem a camada basal dos carcinomas pode ser um evento importante para a progressão tumoral.

P53 est un gène suppresseur de tumeur ubiquitaire qui empêche la prolifération de cellules malignes chez l’humain. En réponse à des dommages à l’ADN ou à des stress cellulaires, p53 entraine l’arrêt du cycle cellulaire et initie la réparation des lésions du génome. Si ces réparations échouent, p53 déclenche alors la mort de la cellule endommagée par apoptose. De plus, p53 présente une forte homologie avec deux autres gènes suppresseurs de tumeur : p63 et p73. Ces trois protéines forment une famille de facteurs de transcription qui protège l’organisme contre le développement de tumeurs. Ce système de défense est enrichi par les multiples isoformes de p53, p63 et p73 dont les rôles sont encore mal décrits. La neutralisation de la fonction de suppression de tumeur de p53, p63 et p73 est un mécanisme clef du développement tumoral auquel participent les mutants hotspots de p53 ainsi que certaines isoformes de p53, p63 et p73 par un effet dominant-négatif. Toutefois, de nombreuses zones d’ombre limitent notre compréhension de ce phénomène. Tout d’abord, l’identification des membres de la famille de p53 impliqués dans l’effet dominant-négatif reste incomplète. Ensuite, les mécanismes responsables de l’effet dominant-négatif sont débattus, suite notamment à l’émergence d’une nouvelle hypothèse impliquant un mécanisme de type prion. Enfin, l’effet dominant-négatif de la famille de p53 pourrait également être mis en cause dans d’autres types de pathologies comme les syndromes développementaux associés à des mutations de p63. Au cours de cette thèse, j’ai étudié l’impact fonctionnel des mutations hotspots de p53 ainsi que celui des principales isoformes de la famille de p53 sur l’activité transcriptionnelle des isoformes actives de p53, p63 et p73. En utilisant comme modèle d’étude un eucaryote simple, la levure S. cerevisiae, nous avons pu démontrer que l’effet dominant-négatif des mutants et isoformes de la famille de p53 repose sur la formation d’hétéro-tétramères entre formes actives et inactives de ces protéines et n’implique pas de mécanisme de type prion. De plus nos travaux ont montré que certains mutants de p53 interfèrent avec les isoformes actives de p63 et p73 par un mécanisme partiellement basé sur la tétramérisation. En outre, nos résultats préliminaires suggèrent que les mutants de p63 impliqués dans les syndromes développementaux EEC, ADULT et NSCL1 exercent également un effet dominant-négatif similaire à celui des mutants de p53. L’identification des mécanismes de l’effet dominant-négatif observé au sein de la famille de p53 permet d’envisager de nouvelles cibles thérapeutiques tant dans les cancers que dans certaines maladies rares du développement humain. / P53 is a ubiquitous tumor suppressor gene that prevents damaged cells from proliferating. Following DNA damage or cellular stress, p53 induces a cell cycle arrest and initiates an attempt to repair the lesions. If the repair fails, p53 triggers the apoptosis of the cell. p53 shares a high homology with two other tumor suppressor genes: p63 and p73. Together they form a family of transcription factors, which are actively protecting the organism from tumor development. This defense network is enriched by multiple N-terminal and C-terminal isoforms of p53, p63 and p73. The loss of p53, p63 and p73 tumor suppression function is a key step of cancer progression. Mutants of p53 and isoforms of p53, p63 and p73 often exhibit a dominant-negative behavior resulting in the loss of p53 tumor suppression activity. However, the extent of the dominant-negative effect within p53 family remains unclear. The mechanisms behind the dominant-negative effect are also debated due to the recent emergence of a prion-like hypothesis. Finally, the dominant-negative effect of p53 family members could be involved in other pathologies such as p63-related developmental syndromes During this PhD, I studied the functional consequences of hotspot mutations of p53 and of the main isoforms of the p53 family on the transcriptional activity of p53, p63 and p73. Using the naïve eukaryotic model S. cerevisiae we have demonstrated that the dominant-negative effect of mutants and isoforms of the p53 family relies on the formation of hetero-tetramers between functional and non-functional members of the family but not on a prion-like mechanism. In addition, certain p53 mutants are able to interfere with p63 and p73 isoforms though a mechanism that is only partially based on tetramerization. Of note, we obtained preliminary results suggesting that mutants of p63, which are involved in EEC, ADULT and NSCL1 developmental syndromes, behave like dominant-negative hotspot mutants of p53. The identification of the mechanisms of the dominant-negative effect occurring within p53 family could lead to new therapeutic targets both in cancer and in rare developmental syndromes.1 EEC : ectrodactyly, ectodermal dysplasia and cleft lip/palate syndrome, ADULT : acro-dermato-ungual-lacrimal-tooth syndrome, NSCL : non-syndromic cleft lip

Le gène TP63 fait partie de la famille du gène suppresseur de tumeur TP53. Il code plusieurs isoformes. L’une d’entre elles, tronquée dans la région amino-terminale et appelée ΔNp63, présente des propriétés oncogéniques. Elle est impliquée dans la progression tumorale et la chimiorésistance. Sa surexpression est fréquente dans certains types de cancers. La première partie de mes travaux a consisté à identifier les facteurs de transcription impliqués dans la régulation du promoteur de ΔNp63. J’ai montré que l’expression de cette isoforme est inhibée par p53 et activée par ΔNp63 elle-même et par la β-caténine, dans des lignées de carcinome hépatocellulaire et de carcinome épidermoïde de l’œsophage. Dans des conditions physiologiques, un des types cellulaires dans lequel ΔNp63 est exprimée est la cellule basale mammaire. Il est admis que les tumeurs mammaires dites basal-like sont issues des cellules basales. Certaines de ces tumeurs présentant une surexpression de ΔNp63, nous avons émis l’hypothèse que ΔNp63 serait impliquée dans la tumorigenèse des cellules basales. Dans la deuxième partie, j’ai montré que l’expression de ΔNp63 peut être augmentée en cultivant les cellules mammaires en présence de surnageant de fibroblastes embryonnaires humains. L’identification de facteurs solubles responsables est en cours. D’autre part, j’ai caractérisé les conséquences biologiques de cette augmentation en termes de prolifération, de motilité et de survie des cellules immatures mammaires normales et tumorales. Les plus grandes modifications observées concernent (i) l’état de différenciation, les cellules surexprimant ΔNp63 présentant un phénotype plus immature ; (ii) la balance entre migration et adhésion qui penche en faveur de cette dernière. ΔNp63 semble donc être au carrefour des mécanismes de prolifération, d’adhésion, de différenciation et de motilité, processus impliqués dans la formation et l’homéostasie des tissus, mais dont l’altération peut conduire à l’initiation et à la progression tumorale ainsi qu’à la dissémination métastatique. Mes travaux apportent des informations sur le rôle de cette protéine dans ces processus et devraient, à terme, permettre de mieux comprendre la genèse de certains cancers, en particulier les carcinomes basal-like / TP63 gene belongs to the TP53 tumor suppressor gene family. It encodes several isoforms. One of these, truncated in its amino-terminal end and called ΔNp63, displays oncogenic properties. It is involved in tumor progression and chemoresistance and is overexpressed in some tumor types. The first part of my work consisted of identifying the transcription factors involved in the regulation of the ΔNp63 promoter. I have shown that ΔNp63 expression is inhibited by p53 and activated by ΔNp63 itself and by β-catenin in hepatocellular carcinoma and esophageal squamous cell carcinoma cell lines. Under physiological conditions, one of the cell types in which ΔNp63 is expressed is the mammary basal cell. The “basal-like” mammary tumor sub-type seems to stem from basal cells. As some of these tumors exhibit overexpression of ΔNp63, we hypothesized that this isoform could be involved in the genesis of basal-like tumors. In the second part, I have shown that ΔNp63 expression can be increased in mammary cells cultivated in the presence of human embryonic fibroblast supernatant. Identifying the soluble factors responsible for this increase is in progress. In parallel, I have evaluated the biological consequences of ΔNp63 overexpression in terms of proliferation, cell motility and survival of normal and malignant immature mammary cells. The main modifications relate to (i) the differentiation status, ΔNp63-overexpressing cells exhibiting a more immature phenotype; (ii) the balance between migration and adhesion that is in favor of this latter. ΔNp63 seems to be at the crossroads of proliferation, adhesion, differentiation and motility, processes implicated in tissue formation and homeostasis, but whose alteration may lead to tumor initiation and progression and to metastatic dissemination. My work provides information on the role of this isoform in these processes and should allow better understanding of the genesis of some tumor types, in particular basal-like breast carcinomas

A terapia foto-dinâmica consiste na irradiação luminosa de um determinado tecido ou microorganismo previamente exposto à ação de um corante foto-sensibilizador. Ela é eficazmente utilizada em neoplasias e em processos infecciosos. No entanto, poucos estudos avaliam o efeito desta terapia em reparação tecidual. Estes trabalhos mostram resultados que variam entre satisfatórios e não-satisfatórios. Além disso, os estudos que envolvem a terapia com laser em baixa intensidade e a terapia foto-dinâmica em reparação tecidual preocupam-se, na maioria das vezes, com a organização e quantificação dos componentes da matriz extra-celular. Estudar o epitélio, em contrapartida, por meio das proteínas expressas pelos queratinócitos é igualmente importante, sabendo-se que a reparação da ferida depende também da organização e proliferação das células epiteliais. Este trabalho avaliou a reparação tecidual de excisões realizadas em dorso de ratos submetidas à irradiação com laser em baixa intensidade ou terapia foto-dinâmica mediada pelo corante azul de metileno. Para tal, realizou-se a análise morfológica e histomorfológica das feridas em determinados tempos experimentais, além da análise imunoistoquímica das citoqueratinas 10 e 14 e p63. Os resultados mostraram que a reparação tecidual foi favorecida com a irradiação laser em baixa intensidade, o que foi confirmado através das análises morfológica e histo-morfológica que mostraram fechamento prévio da ferida para este grupo experimental. Além disso, a expressão de citoqueratina 10 na língua epitelial formada nas feridas pertencentes ao grupo Laser precedeu a expressão da mesma nos outros grupos, o que indicou uma maturação acelerada do epitélio para este grupo. O grupo da terapia foto-dinâmica não apresentou aceleração da reparação tecidual bem como não a prejudicou. Isto sugere que a reparação tecidual frente à irradiação laser é diferente daquela encontrada com a terapia foto-dinâmica. Além disso, não houve atraso da reparação tecidual com a terapia foto-dinâmica, sugerindo que esta terapia foi segura e que devem ser consideradas suas vantagens em situações de infecção. / The photodynamic therapy involves delivering visible light of the appropriate wavelength into a tissue or microorganism previously exposed to a photo-sensitive dye. Its use is widely spread between neoplastic and infeccious diseases. Nevertheless, its effects upon wound healing has not yet been completely verified and the few studies concerning this subject present whether good or bad results. In addition, studies that involve low intensity laser therapy or photodynamic therapy on wound healing concern mostly on the organization and quantification of the extracellular matrix components. Studying the epithelium, on the other hand, by the keratinocyte expressed proteins is equally important, once the wound healing depends also of the organization and proliferation of the epithelial cells. This study evaluated the wound healing of excisions performed on the back of rats submitted to low intensity laser therapy or photodynamic therapy mediated by methylene blue dye. Morphological and histo-morphological analysis of the wounds in pre-determined periods were performed, as well as immunohistochemistry of citokeratins 10 and 14 and p63. The results showed that the wound healing was enhanced by the low intensity laser therapy, which was confirmed by the morphological and histomorphological analysis. The wound closure was previously seen for the laser group. The citokeratin 10 expression on the epithelial tongue of the wounds that belong to the laser group preceded the expression in the other groups, which indicated an accelerated maturation of this epithelium. The photodynamic therapy group did not present accelerated wound healing but did not present any delay as well. This suggests that the wound healing found for the laser group differs from that found for the photodynamic therapy group. Moreover, the lack of delay presented by the photodynamic therapy suggests a safe therapy with advantages regarding disinfection that should be considered in specific situations.

O Brasil está entre os países com os maiores índices de carcinoma epidermóide oral (CEO). O gene p63 é um análogo do supressor tumoral p53 e a influência da expressão de ambos no prognóstico do CEO ainda necessita ser melhor investigada. O envolvimento do papilomavírus humano (HPV) no CEO é outro fator ainda não elucidado. Nosso estudo objetivou avaliar os pacientes com CEO no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, assim como também investigar a relação entre a presença do HPV e a imunoexpressão das proteínas p53 e p63 com alguns parâmetros relevantes ao prognóstico deste tumor. Os seguintes dados foram obtidos dos prontuários médicos de 424 pacientes: idade, gênero, localização e tamanho da lesão primária, história pregressa, consumo de tabaco e álcool, exposição actínica, traumatismo por prótese, recidivas, metástases, diferenciação tumoral, tratamento, sobrevida e óbitos. Cento e vinte e seis pacientes foram selecionados para o estudo da sobrevida, 106 para o estudo imunohistoquímico, 45 para a investigação IHQ com amostras pareadas (AP) e 87 para a reação em cadeia da polimerase para detecção do HPV e análise multivariada. Os tumores tiveram predominância em pacientes masculinos na 6ª década de vida, havendo após esta faixa etária um aumento dos casos no gênero feminino e menor sobrevida. A língua foi a região mais acometida, e as lesões em lábio inferior demonstraram maior atraso na procura pelo tratamento e relatos de exposição actínica desprotegida. As recidivas ocorreram em 30% dos pacientes, 28,8% tiveram metástases e 13,2% foram a óbito. Os tumores bem diferenciados foram predominantes (47,7%), e a sobrevida livre da doença (SLD) e a sobrevida global (SG) em cinco anos foram 19% e 24,3%, respectivamente. A imunoexpressão de p63 (87,8%) nos tumores foi maior que a de p53 (52,8%), mas os tumores p53 positivos estiveram significativamente associados aos casos de metástases. Os tumores p53 negativos e com forte intensidade de imunoexpressão de p63 demonstraram melhor SG. No estudo com AP, os tumores com elevada imunoexpressão de p63 demonstraram melhor sobrevida e as neoplasias p53 negativas tiveram melhor SLD. A maioria dos casos demonstrou um padrão concordante de imunoexpressão nas AP (73,3% para p53 e 53,3% para p63, respectivamente). O HPV foi encontrado em 18 (10,4%) amostras de CEO, correspondendo a 17 (19,5%) pacientes. Foram encontradas amostras positivas em 10 (11,5%) tumores primários e em 8 (9,2%) AP. Foram identificados os subtipos de HPV 16 e 18 em 4 (22,2%) e 3 (16,7%) das amostras positivas, respectivamente. Em 6 (33,3%) amostras foi encontrada a presença de ambos os subtipos e em 5 (27,8%) amostras não foi identificado. As amostras HPV positivas foram significativamente associadas aos pacientes não fumantes. Diferenças significativas relacionadas ao prognóstico do CEO na análise multivariada foram encontradas para idade, localização tumoral e p53. A imunoexpressão de p53 e a baixa intensidade da imunoexpressão de p63 demonstraram relação com pior prognóstico. Uma associação do HPV à carcinogênese oral foi observada nos pacientes não fumantes. / Brazil is among the countries with the largest indexes of oral squamous cell carcinoma (OSCC). The role of p53 and p63 in the OSCC prognosis is still debatable. The involvement of the human papilomavirus (HPV) in CEO is still another factor no elucidated. Our study aimed to evaluate the patients with OSCC diagnosed in the Teaching Hospital of the Ribeirao Preto Medical School of the Sao Paulo University, as well as to investigate the relationship between the p53 and p63 proteins immunoexpression and the HPV presence with some relevant clinicopathological parameters to the tumor prognostic. The data obtained from the medical files of 424 patients were: age, gender, primary tumor (PT) site and size, evolution time, tobacco and alcohol consumption, actinic radiation exposition, prosthesis trauma reports, recurrences, metastases, tumoral differentiation, treatment, survival and deaths. One hundred twenty-six patients were selected for the survival study, 106 for the immunohistochemical investigation, 45 for the IHQ analysis with matched samples (MS), and 87 for the polymerase chain reaction test of HPV and multivariate analysis. Tumors were prevalent in masculine patients around the 6th decade of life, with an increase in feminine gender and a smaller survival after this age. Tongue was the prevalent site, and the lower lip lesions had the larger delay to look for treatment and high reports of unprotected actinic exposition. There were recurrences in 30% of the patients, 28.8% had metastases and 13.2% died. Well differentiated tumors were more prevalent in this study (47.7%), and the five years disease free survival (DFS) and overall survival (OS) were 19% and 24.3%, respectively. The p63 immunoexpression (87.8%) in tumors was higher than p53 (52.8%), and the p53 positive tumors were significantly associated with metastases. The p53 negative tumors and those with strong p63 immunoexpression intensity demonstrated better OS. In the MS study, tumors with high p63 immunoexpression demonstrated better survival and those p53 negative had better DFS. Most of cases demonstrated a concordant immunoexpression pattern in MS (73.3% for p53 and 53.3% for p63, respectively). HPV was found in 18 (10.4%) OSCC samples, corresponding to 17 (19.5%) patients. There were positive samples in 10 (11.5%) PT and 8 (9.2%) MS. The subtypes HPV 16 and 18 were identified in 4 (22.2%) and 3 (16.7%) of the positive samples, respectively. Presence of both subtypes was found in 6 (33.3%) samples and in 5 (27.8%) samples they were not identified. The HPV positive samples were significantly associated with non-smoker patients. Significant differences related to the OSCC prognostic were found in multivariate analysis for age, tumoral site and p53. The p53 immunoexpression and low intensity of p63 immunoexpression demonstrated relation with worse prognostic, and a HPV association to oral carcinogenesis was verified in the non-smoker patients.

O Brasil está entre os países com os maiores índices de carcinoma epidermóide oral (CEO). O gene p63 é um análogo do supressor tumoral p53 e a influência da expressão de ambos no prognóstico do CEO ainda necessita ser melhor investigada. O envolvimento do papilomavírus humano (HPV) no CEO é outro fator ainda não elucidado. Nosso estudo objetivou avaliar os pacientes com CEO no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, assim como também investigar a relação entre a presença do HPV e a imunoexpressão das proteínas p53 e p63 com alguns parâmetros relevantes ao prognóstico deste tumor. Os seguintes dados foram obtidos dos prontuários médicos de 424 pacientes: idade, gênero, localização e tamanho da lesão primária, história pregressa, consumo de tabaco e álcool, exposição actínica, traumatismo por prótese, recidivas, metástases, diferenciação tumoral, tratamento, sobrevida e óbitos. Cento e vinte e seis pacientes foram selecionados para o estudo da sobrevida, 106 para o estudo imunohistoquímico, 45 para a investigação IHQ com amostras pareadas (AP) e 87 para a reação em cadeia da polimerase para detecção do HPV e análise multivariada. Os tumores tiveram predominância em pacientes masculinos na 6ª década de vida, havendo após esta faixa etária um aumento dos casos no gênero feminino e menor sobrevida. A língua foi a região mais acometida, e as lesões em lábio inferior demonstraram maior atraso na procura pelo tratamento e relatos de exposição actínica desprotegida. As recidivas ocorreram em 30% dos pacientes, 28,8% tiveram metástases e 13,2% foram a óbito. Os tumores bem diferenciados foram predominantes (47,7%), e a sobrevida livre da doença (SLD) e a sobrevida global (SG) em cinco anos foram 19% e 24,3%, respectivamente. A imunoexpressão de p63 (87,8%) nos tumores foi maior que a de p53 (52,8%), mas os tumores p53 positivos estiveram significativamente associados aos casos de metástases. Os tumores p53 negativos e com forte intensidade de imunoexpressão de p63 demonstraram melhor SG. No estudo com AP, os tumores com elevada imunoexpressão de p63 demonstraram melhor sobrevida e as neoplasias p53 negativas tiveram melhor SLD. A maioria dos casos demonstrou um padrão concordante de imunoexpressão nas AP (73,3% para p53 e 53,3% para p63, respectivamente). O HPV foi encontrado em 18 (10,4%) amostras de CEO, correspondendo a 17 (19,5%) pacientes. Foram encontradas amostras positivas em 10 (11,5%) tumores primários e em 8 (9,2%) AP. Foram identificados os subtipos de HPV 16 e 18 em 4 (22,2%) e 3 (16,7%) das amostras positivas, respectivamente. Em 6 (33,3%) amostras foi encontrada a presença de ambos os subtipos e em 5 (27,8%) amostras não foi identificado. As amostras HPV positivas foram significativamente associadas aos pacientes não fumantes. Diferenças significativas relacionadas ao prognóstico do CEO na análise multivariada foram encontradas para idade, localização tumoral e p53. A imunoexpressão de p53 e a baixa intensidade da imunoexpressão de p63 demonstraram relação com pior prognóstico. Uma associação do HPV à carcinogênese oral foi observada nos pacientes não fumantes. / Brazil is among the countries with the largest indexes of oral squamous cell carcinoma (OSCC). The role of p53 and p63 in the OSCC prognosis is still debatable. The involvement of the human papilomavirus (HPV) in CEO is still another factor no elucidated. Our study aimed to evaluate the patients with OSCC diagnosed in the Teaching Hospital of the Ribeirao Preto Medical School of the Sao Paulo University, as well as to investigate the relationship between the p53 and p63 proteins immunoexpression and the HPV presence with some relevant clinicopathological parameters to the tumor prognostic. The data obtained from the medical files of 424 patients were: age, gender, primary tumor (PT) site and size, evolution time, tobacco and alcohol consumption, actinic radiation exposition, prosthesis trauma reports, recurrences, metastases, tumoral differentiation, treatment, survival and deaths. One hundred twenty-six patients were selected for the survival study, 106 for the immunohistochemical investigation, 45 for the IHQ analysis with matched samples (MS), and 87 for the polymerase chain reaction test of HPV and multivariate analysis. Tumors were prevalent in masculine patients around the 6th decade of life, with an increase in feminine gender and a smaller survival after this age. Tongue was the prevalent site, and the lower lip lesions had the larger delay to look for treatment and high reports of unprotected actinic exposition. There were recurrences in 30% of the patients, 28.8% had metastases and 13.2% died. Well differentiated tumors were more prevalent in this study (47.7%), and the five years disease free survival (DFS) and overall survival (OS) were 19% and 24.3%, respectively. The p63 immunoexpression (87.8%) in tumors was higher than p53 (52.8%), and the p53 positive tumors were significantly associated with metastases. The p53 negative tumors and those with strong p63 immunoexpression intensity demonstrated better OS. In the MS study, tumors with high p63 immunoexpression demonstrated better survival and those p53 negative had better DFS. Most of cases demonstrated a concordant immunoexpression pattern in MS (73.3% for p53 and 53.3% for p63, respectively). HPV was found in 18 (10.4%) OSCC samples, corresponding to 17 (19.5%) patients. There were positive samples in 10 (11.5%) PT and 8 (9.2%) MS. The subtypes HPV 16 and 18 were identified in 4 (22.2%) and 3 (16.7%) of the positive samples, respectively. Presence of both subtypes was found in 6 (33.3%) samples and in 5 (27.8%) samples they were not identified. The HPV positive samples were significantly associated with non-smoker patients. Significant differences related to the OSCC prognostic were found in multivariate analysis for age, tumoral site and p53. The p53 immunoexpression and low intensity of p63 immunoexpression demonstrated relation with worse prognostic, and a HPV association to oral carcinogenesis was verified in the non-smoker patients.

A terapia foto-dinâmica consiste na irradiação luminosa de um determinado tecido ou microorganismo previamente exposto à ação de um corante foto-sensibilizador. Ela é eficazmente utilizada em neoplasias e em processos infecciosos. No entanto, poucos estudos avaliam o efeito desta terapia em reparação tecidual. Estes trabalhos mostram resultados que variam entre satisfatórios e não-satisfatórios. Além disso, os estudos que envolvem a terapia com laser em baixa intensidade e a terapia foto-dinâmica em reparação tecidual preocupam-se, na maioria das vezes, com a organização e quantificação dos componentes da matriz extra-celular. Estudar o epitélio, em contrapartida, por meio das proteínas expressas pelos queratinócitos é igualmente importante, sabendo-se que a reparação da ferida depende também da organização e proliferação das células epiteliais. Este trabalho avaliou a reparação tecidual de excisões realizadas em dorso de ratos submetidas à irradiação com laser em baixa intensidade ou terapia foto-dinâmica mediada pelo corante azul de metileno. Para tal, realizou-se a análise morfológica e histomorfológica das feridas em determinados tempos experimentais, além da análise imunoistoquímica das citoqueratinas 10 e 14 e p63. Os resultados mostraram que a reparação tecidual foi favorecida com a irradiação laser em baixa intensidade, o que foi confirmado através das análises morfológica e histo-morfológica que mostraram fechamento prévio da ferida para este grupo experimental. Além disso, a expressão de citoqueratina 10 na língua epitelial formada nas feridas pertencentes ao grupo Laser precedeu a expressão da mesma nos outros grupos, o que indicou uma maturação acelerada do epitélio para este grupo. O grupo da terapia foto-dinâmica não apresentou aceleração da reparação tecidual bem como não a prejudicou. Isto sugere que a reparação tecidual frente à irradiação laser é diferente daquela encontrada com a terapia foto-dinâmica. Além disso, não houve atraso da reparação tecidual com a terapia foto-dinâmica, sugerindo que esta terapia foi segura e que devem ser consideradas suas vantagens em situações de infecção. / The photodynamic therapy involves delivering visible light of the appropriate wavelength into a tissue or microorganism previously exposed to a photo-sensitive dye. Its use is widely spread between neoplastic and infeccious diseases. Nevertheless, its effects upon wound healing has not yet been completely verified and the few studies concerning this subject present whether good or bad results. In addition, studies that involve low intensity laser therapy or photodynamic therapy on wound healing concern mostly on the organization and quantification of the extracellular matrix components. Studying the epithelium, on the other hand, by the keratinocyte expressed proteins is equally important, once the wound healing depends also of the organization and proliferation of the epithelial cells. This study evaluated the wound healing of excisions performed on the back of rats submitted to low intensity laser therapy or photodynamic therapy mediated by methylene blue dye. Morphological and histo-morphological analysis of the wounds in pre-determined periods were performed, as well as immunohistochemistry of citokeratins 10 and 14 and p63. The results showed that the wound healing was enhanced by the low intensity laser therapy, which was confirmed by the morphological and histomorphological analysis. The wound closure was previously seen for the laser group. The citokeratin 10 expression on the epithelial tongue of the wounds that belong to the laser group preceded the expression in the other groups, which indicated an accelerated maturation of this epithelium. The photodynamic therapy group did not present accelerated wound healing but did not present any delay as well. This suggests that the wound healing found for the laser group differs from that found for the photodynamic therapy group. Moreover, the lack of delay presented by the photodynamic therapy suggests a safe therapy with advantages regarding disinfection that should be considered in specific situations.

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