Melanoma is one of the most aggressive types of cancer. It originates from the transformation of melanocytes present in the epidermal/dermal junction of the human skin. It is commonly accepted that melanomagenesis is influenced by the interaction of environmental factors, genetic factors, as well as tumor-host interactions. DNA photoproducts induced by UV radiation are, in normal cells, repaired by the nucleotide excision repair (NER) pathway. The prominent role of NER in cancer resistance is well exemplified by patients with Xeroderma Pigmentosum (XP). This disease results from mutations in the components of the NER pathway, such as XPA and XPC proteins. In humans, NER pathway disruption leads to the development of skin cancers, including melanoma. Similar to humans afflicted with XP, Xpa and Xpc deficient mice show high sensibility to UV light, leading to skin cancer development, except melanoma. The Endothelin 3 (Edn3) signaling pathway is essential for proliferation, survival and migration of melanocyte precursor cells. Excessive production of Edn3 leads to the accumulation of large numbers of melanocytes in the mouse skin, where they are not normally found. In humans, Edn3 signaling pathway has also been implicated in melanoma progression and its metastatic potential. The goal of this study was the development of the first UV-induced melanoma mouse model dependent on the over-expression of Edn3 in the skin. The UV-induced melanoma mouse model reported here is distinguishable from all previous published models by two features: melanocytes are not transformed a priori and melanomagenesis arises only upon neonatal UV exposure. In this model, melanomagenesis depends on the presence of Edn3 in the skin. Disruption of the NER pathway due to the lack of Xpa or Xpc proteins was not essential for melanomagenesis; however, it enhanced melanoma penetrance and decreased melanoma latency after one single neonatal erythemal UV dose. Exposure to a second dose of UV at six weeks of age did not change time of appearance or penetrance of melanomas in this mouse model. Thus, a combination of neonatal UV exposure with excessive Edn3 in the tumor microenvironment is sufficient for melanomagenesis in mice; furthermore, NER deficiency exacerbates this process.

The cancers of the skin, melanoma and the keratinocyte cancers, basal cell andsquamous cell carcinomas (BCC and SCC), are among the most common cancersin white populations. While ultraviolet radiation (UVR) is their principal cause,links with non-UVR-related factors have also been noted. Ultimately, theinteraction of these elements results in malignancy however, understanding oftheir specific contributions remains incomplete. This thesis reports findings fromsix studies aiming to investigate gaps in current knowledge of the role of UVR andnon-UVR-related risk factors on skin cancer. The papers are groupedaccording to the aspects of skin cancer epidemiology and aetiology they address. The first two papers address the descriptive epidemiology of melanoma inEngland, a country with low ambient solar UVR. They arise from ecologicalstudies using national melanoma registration data and document rising trends inmelanoma incidence by anatomic site (Paper 1), and by region of residence andsocio-economic deprivation (Paper 2). Their findings were consistent with thesuggestion that increases in recreational UVR exposure are driving rises inmelanoma rates. These results emphasise both the need to closely monitor UVRexposure and melanoma trends and the importance of public health campaigns. The second group of three papers considers the assessment of associations ofnutritional factors with keratinocyte cancer. Two studies use data from aprospective cohort to evaluate the relationship between dietary intake (Paper 3)and blood concentrations (Paper 4) of omega-3 and omega-6 polyunsaturatedfatty acids (PUFA) in relation to BCC and SCC risk. Associations with both PUFAtypes were observed. In addition, Paper 5, a three-way correlational assessment,demonstrated that questionnaire and blood circulating levels of omega-3 PUFAwere highly correlated with measures of skin bioavailability. Collectively, thesestudies give evidence for associations of these nutrients with skin cancer and forthe utility of both intake and biomarker measures for assessing the relationships. The final paper explores the relationship between a widely cited non-UVR riskfactor, namely scars and cancers of the skin. It reports a systematic review of allpublished observational studies quantifying this association. While innumerablecase reports were found, quantitative analyses were rare. The review identifieda major gap in the literature where knowledge of scar malignancies is notevidence-based, but rather founded mainly on cumulative anecdotal reporting. Taken together, this body of published work highlights the largely unrecognisedcomplexity of the aetiology of cancers of the skin. Future research must bebroad in scope in order to advance understanding of the interaction betweenUVR and other risk factors and to provide a base for health messages aimed atreducing the burden of these malignancies.

The development of checkpoint immunotherapy has been a paradigm shift in the treatment of cancer, leading to dramatic improvement in treatment outcomes across a broad range of tumor types. Nevertheless, our current understanding of the tumor immune microenvironment and mediators of resistance to therapy are limited. The recent development of high-throughput single-cell RNA-Sequencing (scRNA-Seq) technology has opened up an unprecedented window into the transcriptional states of distinct tumor-infiltrating immune and stromal cells. However, even this technology has its biological limitations, with very high levels of data dropout induced by low total mRNA molecules and capture efficiency. This thesis explores the application of a transcriptional regulatory protein activity inference approach to single-cell data in order to resolve gene dropout and more deeply characterize upstream drivers of cell state within the micro-environment of several distinct tumor types. To this end, algorithms for inference of protein activity, drug sensitivity, and cell-cell interaction have been adapted to scRNA-Seq data, along with an approach for querying enrichment of single-cell-derived population marker gene sets patient-by-patient in larger bulk-RNA-Seq cohorts. By applying these tools systematically, we have identified distinct cellular sub-populations associated with clinical outcome in different tumor types, including a novel population of C1Q+/TREM2+/APOE+ macrophages associated with post-surgical tumor recurrence in clear cell renal carcinoma, a sub-population of fibroblasts associated with improved response to immunotherapy in head and neck squamous cell carcinoma, tumor cell subpopulations with distinct inferred drug sensitivities in cholangiocarcinoma and prostate cancer, as well as tumor-specific regulatory T-cells (Tregs), active as a mechanism of immunotherapy resistance across a range of tumor types. In ongoing clinical trials from both primary and metastatic prostate cancer as well as clear cell renal carcinoma, we are able to assess which of these populations are enriched in non-responders to checkpoint immunotherapy. The proteomic master regulators of each of these single-cell types have direct utility as potential biomarkers for treatment response, but they may also be therapeutically modulated as novel targets for combination immunotherapy, potentially improving treatment response rates and treatment outcomes in future clinical trials. Finally, this thesis also presents a discovery-to-validation platform to accelerate micro-environment-directed drug repurposing in the context of immunotherapy resistance and rapid CRISPRko validation of novel therapeutic targets. This platform has been developed specifically to validate newly identified master regulators of tumor-specific immunosuppressive regulatory T-cells (Tregs), resulting in discovery of low-dose gemcitabine as a tumor-specific Treg-modulating drug synergistic with anti-PD1 checkpoint immunotherapy and TRPS1 as a proteomic master regulator with clinically significant effect on tumor Treg-infiltrating and tumor growth rate. However, the platform itself may be readily extended in future work to prioritize agents against immunosuppressive macrophage and fibroblast populations for clinical development and trials. As we have discovered, different cancers have different populations of cells driving therapy response and resistance. Taken together, the analytical and validation tools presented in this thesis represent an opportunity to tailor future immuno-therapies at the single-cell level to particular tumor types and to individual patients.

Carcinoma de Células Renais (CCR) representa uma família de tumores distintos com evolução clínica imprevisível. Uma variedade de moléculas tem sido avaliada como marcadores prognósticos para CCR. Ciclina D1, uma proteína reguladora do ciclo celular, encontra-se superexpressa em vários tumores primários. Nosso objetivo é avaliar sua expressão como marcador prognóstico em CCR. Antes disso, traçamos um perfil clínico e histopatológico da amostra e verificamos sua relação com os fatores prognósticos considerados clássicos pela literatura. 109 espécimes de pacientes diagnosticados com CCR foram obtidos entre 2005 e 2010 no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto USP e submetidos à análise imunoistoquímica juntamente com 07 amostras de tecido renal normal. A maior parte das características epidemiológicas e clínicas de nossa amostra foi similar àquelas descritas na literatura mundial. Houve predomínio do gênero masculino, da raça branca, com idade próxima a 60 anos, frequência de pacientes assintomáticos em torno de 36% e grande prevalência do CCR de células claras (71,55%). A mortalidade específica da doença foi de 13,76%, sendo o CCR de células claras o tipo mais frequente entre os óbitos e casos metastáticos. Os casos que exibiram má evolução clínica, definida pela ocorrência de metástase e/ou óbito por CCR (22,01%), estiveram associados à presença de sintomas ao diagnóstico, maior tamanho tumoral, grupo de estágio alto (III ou IV), grau nuclear de Fuhrman alto (3 ou 4), presença de necrose e de diferenciação sarcomatóide no tumor, além de outros fatores histológicos desfavoráveis (p < 0,01). Isso indica que as variáveis utilizadas na avaliação de prognóstico em países desenvolvidos podem ser aplicadas aos nossos pacientes. Não houve expressão imunoistoquímica de Ciclina D1 nos casos de tecido renal normal. Observou-se heterogeneidade de marcação nuclear intratumoral no total de casos e menor expressão proteica entre os CCR papilífero e cromófobo. Pacientes com tumores com Ciclina D1baixa (até 30% de células positivas) apresentaram má evolução clínica (p = 0,03), maior tamanho tumoral (p = 0,01), presença de sintomas ao diagnóstico (p = 0,04), grau nuclear alto (p = 0,001), presença de necrose (p = 0,004) e de diferenciação sarcomatóide (p = 0,04) no tumor, além de menor sobrevida sem metástase e/ou óbito por CCR (p = 0,03). Após análise multivariada, a expressão de Ciclina D1 não apresentou valor prognóstico independente para má evolução clínica, embora tenha aumentado levemente a acurácia prognóstica do modelo adotado. Em todas as análises realizadas para o CCR de células claras isoladamente, observamos significância estatística semelhante à do total de casos (CCR). Nosso estudo demonstrou que: a proteína Ciclina D1 encontra-se superexpressa em CCR; os tipos de CCR parecem exibir diferentes padrões de marcação imunoistoquímica da Ciclina D1; alta marcação da proteína (acima de 30% de células positivas) esteve associada à boa evolução clínica e à maioria dos fatores prognósticos favoráveis bem estabelecidos na literatura. Novas investigações são necessárias para descobrir que mecanismos levam a seu acúmulo nas células neoplásicas e quais outros eventos podem estar contribuindo para a progressão da doença. / Renal Cell Carcinoma (RCC) is a family of distinct tumors with unpredictable clinical outcome. A variety of molecules have been evaluated as prognostic markers for RCC. Cyclin D1, a cell cycle regulatory protein, is overexpressed in several primary tumors. Our purpose is to evaluate its expression as a prognostic marker in RCC. Before that, we drew a clinical and histopathological profile of the sample and verified its relationship with prognostic factors regarded as classics in literature. 109 specimens from patients diagnosed with RCC were obtained between 2005 and 2010 at Hospital das Clínicas - Ribeirão Preto School of Medicine USP and submitted to immunohistochemical analysis, along with 07 normal kidney tissue samples. Most epidemiological and clinical characteristics of our sample were similar to those described in the literature. There was a predominance of male, Caucasian, aged about 60 years, the frequency of asymptomatic patients around 36%, and high prevalence of clear cell RCC (71.55%). The disease-specific mortality was 13.76%, being the clear cell RCC the most frequent type among deaths and metastatic cases. Cases that exhibited poor clinical outcome, defined by the occurrence of metastasis and/or death by RCC (22.01%), were related to the presence of symptoms at diagnosis, larger tumor size, high stage group (III or IV), high Fuhrman nuclear grade (3 or 4), presence of necrosis and sarcomatoid differentiation in the tumor and other unfavorable histological factors (p < 0.01). This indicates that the variables used in the assessment of prognosis in developed countries can be applied to our patients. There was no immunohistochemical expression of Cyclin D1 in cases of normal kidney tissue. There was intratumoral heterogeneity in nuclear staining in all cases and lower protein expression among papillary and chromophobe RCC. Patients with Cyclin D1low tumors (up to 30% positive cells) showed poor clinical outcome (p = 0.03), larger tumor size (p = 0.01), presence of symptoms at diagnosis (p = 0.04), high nuclear grade (p = 0.001), presence of necrosis (p = 0.004) and sarcomatoid differentiation (p = 0.04) in the tumor and lower survival without metastasis and/or death by RCC (p = 0.03). After multivariate analysis, the expression of Cyclin D1 showed no independent prognostic value for poor clinical outcome, although it has slightly increased the prognostic accuracy of the model adopted. In all analyzes performed for clear cell RCC alone, we observed statistical significance similar to that of the total cases (RCC). Our study showed that: Cyclin D1 protein is overexpressed in RCC; RCC types seem to exhibit different patterns of immunohistochemical staining for Cyclin D1; high protein expression (over 30% positive cells) was related to good clinical outcome and to most favorable prognostic factors well established in the literature. Further investigations are necessary to reveal which mechanisms lead to its accumulation in neoplastic cells and what other events might be contributing to the progression of the disease.

INTRODUÇÃO: A ressecção do ramo ascendente da mandíbula foi, durante várias décadas, considerada o tratamento de eleição para os tumores da loja amigdalina e região retromolar, independente do grau de acometimento do osso mandibular, ocasionando um déficit funcional e estético considerável, muitas vezes, com prejuízos irreparáveis à qualidade de vida, às vezes desnecessário. Assim, a ressecção marginal do osso mandibular surgiu como uma alternativa de tratamento viável, uma vez que a manutenção de um segmento do ramo mandibular, em lesões sem comprometimento ósseo, não aumenta os índices de recidiva, tampouco compromete os princípios de radicalidade oncológica. OBJETIVO E MÉTODOS: Por meio de estudo retrospectivo de Outubro de 1994 a Dezembro de 2001, foram comparados 42 pacientes portadores de tumores avançados de região retromolar e loja amigdalina, sendo 20 deles submetidos a ressecção marginal do osso mandibular e 22 submetidos a ressecção do ramo ascendente da mandíbula, em relação a complicações, seqüela de procedimentos, recidiva locorregional e sobrevida. RESULTADOS: Dos 20 pacientes tratados com mandibulectomia marginal, avaliados por um período de 9 a 60 meses, sete (35%) pacientes morreram com doença, com sobrevida mínima de 09 meses, 3 por recidiva local, 3 por recidiva regional e 1 por recidiva locorregional. Um paciente morreu no pós-operatório imediato. Na avaliação da peça cirúrgica encontramos todas as margens livres, considerada exígua em profundidade em dois pacientes, um deles falecido por recidiva local. Houve disseminação linfonodal em 15 pacientes sendo com ruptura extracapsular em 4, encontrada em 2 pacientes com recidiva regional. O controle locorregional foi obtido em 63% dos pacientes. Dos 22 pacientes tratados com ressecção segmentar do osso mandibular, com intervalo de seguimento de 14 a 60 meses, 8 (36,4%) morreram pela doença, com sobrevida mínima de 9 meses, 5 por recidiva local e 3 por recidiva à distância. Um paciente morreu no pós-operatório imediato. As margens foram livres em 20 pacientes e, em 3 exíguas, um deles falecido por recidiva local. Houve disseminação linfonodal em 12 pacientes com ruptura extracapsular em 7 pacientes. O controle locorregional foi obtido em 61% dos pacientes. Na curva de análise de sobrevida, pelo método de Kaplan-Meier, o grupo tratado com mandibulectomia marginal apresentou uma taxa de 42%, com intervalo de 31 a 52 meses, erro padrão de 5 meses e intervalo de confiança de 95% e o grupo tratado com ressecção segmentar 38% com intervalo de 27 a 48 meses, erro padrão de 5 meses, um intervalo de confiança de 95%. A comparação pelo teste de Log Rank, não paramétrico apresentou p<0,8329 e pelo teste t-Student p< 0,621 ambos não significantes. As principais complicações foram a infecção local em 5 (11,9%) pacientes e a fístula orocutânea em 4 (9,5%). Houve uma fratura da placa de titânio, dois pacientes evoluíram com osteorradionecrose e nove com disfunção da articulação têmporo-mandibular. CONCLUSÕES: Não houve diferenças estatisticamente significantes entre os grupos de ressecção marginal e segmentar nos critérios analisados. Portanto, a conservação do ramo ascendente da mandíbula, em lesões que não apresentem envolvimento mandibular, mesmo avançadas, não aumenta o índice de recidiva. / INTRODUCTION: For several decades, resection of the ascending ramus of the mandible was considered to be mandatory for the treatment of tonsil and retromolar trigone tumours, independent from the damage degree of the mandibular bone, causing considerable functional and aesthetic deficit, many times with irreparable quality of life loss, sometimes unnecessary. Thus, marginal resection of the mandibular bone appeared as a feasible alternative treatment, since maintaining a segment of the mandibular ramus in lesions without bone involvement did not increase the recurrence indexes or compromise the principles of oncological radicalness. OBJECTIVES AND METHODS: Through a retrospective study from October 1994 to December 2001, 42 patients with advanced retromolar and tonsil tumors were compared, 20 undergoing marginal resection of the mandibular bone and 22 undergoing segmental resection of the ascending ramus of the mandible, with regard complications, injury originated from the procedure, locoregional recurrence and survival. RESULTS: From the 20 patients undergoing to marginal mandibulectomy, assessed for a period of 09 to 60 months, seven (35%) patients died of the disease, with a minimal survival of 9 months: 3 due to local recurrence, 3 due to regional recurrence and 1 due to local and regional recurrence. One patient died in the immediate postoperative period. When assessing the surgical part, all the margins were found to be free and in two patients, were considered to be of little depth, one of them being found in one of the patients that died from local recurrence. There was lymph nodal dissemination in 15 patients, with capsular rupture in 4, of which two presented regional recurrence. The locoregional control was obtained in 63% of the patients. From the 22 patients undergoing to segmental resection of the mandibular bone, with a follow-up varying from 14 to 60 months, 8 (36.4%) died of the disease, with a minimum survival of 9 months, 5 due to local recurrence and 3 due to distant recurrence. One patient died in the immediate postoperative period. The surgical margins were considered free from disease in 20 patients and, in three they were too small, one patient died of local recurrence. There was lymph nodal dissemination in 12 patients, and 7 presented capsular rupture. The locoregional control was obtained in 61% of the patients. In the survival analysis curve, by the Kaplan-Meier method, the group submitted to marginal mandibulectomy presented with a rate of 42%, with an interval of 31 to 52 months, standard error of 5 months and confidence interval of 95%, and the group submitted to segmentary resection, 38% with an interval of 27 to 48 months, a standard error of 5 months, and a confidence interval of 95%. The comparison using the non-parametric Log-Rank test presented p<0.8326 and the t-Student test p< 0.621, both not statistically significant. The main complications were local infection in 5 (11.9%) patients and oro-cutaneous fistula in 4 (9.5%). There was one titanium plate fracture, two patients developed osteoradionecrosis and nine temporo-mandibular dysfunction. CONCLUSIONS: There weren t statistically significant differences between the marginal and the segmental resection groups in relation to the analyzed criteria. So, the preservation of the ascending ramus of the mandible, in lesions which do not present mandible commitment, even if not advanced, doesn t increase the recurrence rate.

INTRODUÇÃO: A ressecção do ramo ascendente da mandíbula foi, durante várias décadas, considerada o tratamento de eleição para os tumores da loja amigdalina e região retromolar, independente do grau de acometimento do osso mandibular, ocasionando um déficit funcional e estético considerável, muitas vezes, com prejuízos irreparáveis à qualidade de vida, às vezes desnecessário. Assim, a ressecção marginal do osso mandibular surgiu como uma alternativa de tratamento viável, uma vez que a manutenção de um segmento do ramo mandibular, em lesões sem comprometimento ósseo, não aumenta os índices de recidiva, tampouco compromete os princípios de radicalidade oncológica. OBJETIVO E MÉTODOS: Por meio de estudo retrospectivo de Outubro de 1994 a Dezembro de 2001, foram comparados 42 pacientes portadores de tumores avançados de região retromolar e loja amigdalina, sendo 20 deles submetidos a ressecção marginal do osso mandibular e 22 submetidos a ressecção do ramo ascendente da mandíbula, em relação a complicações, seqüela de procedimentos, recidiva locorregional e sobrevida. RESULTADOS: Dos 20 pacientes tratados com mandibulectomia marginal, avaliados por um período de 9 a 60 meses, sete (35%) pacientes morreram com doença, com sobrevida mínima de 09 meses, 3 por recidiva local, 3 por recidiva regional e 1 por recidiva locorregional. Um paciente morreu no pós-operatório imediato. Na avaliação da peça cirúrgica encontramos todas as margens livres, considerada exígua em profundidade em dois pacientes, um deles falecido por recidiva local. Houve disseminação linfonodal em 15 pacientes sendo com ruptura extracapsular em 4, encontrada em 2 pacientes com recidiva regional. O controle locorregional foi obtido em 63% dos pacientes. Dos 22 pacientes tratados com ressecção segmentar do osso mandibular, com intervalo de seguimento de 14 a 60 meses, 8 (36,4%) morreram pela doença, com sobrevida mínima de 9 meses, 5 por recidiva local e 3 por recidiva à distância. Um paciente morreu no pós-operatório imediato. As margens foram livres em 20 pacientes e, em 3 exíguas, um deles falecido por recidiva local. Houve disseminação linfonodal em 12 pacientes com ruptura extracapsular em 7 pacientes. O controle locorregional foi obtido em 61% dos pacientes. Na curva de análise de sobrevida, pelo método de Kaplan-Meier, o grupo tratado com mandibulectomia marginal apresentou uma taxa de 42%, com intervalo de 31 a 52 meses, erro padrão de 5 meses e intervalo de confiança de 95% e o grupo tratado com ressecção segmentar 38% com intervalo de 27 a 48 meses, erro padrão de 5 meses, um intervalo de confiança de 95%. A comparação pelo teste de Log Rank, não paramétrico apresentou p<0,8329 e pelo teste t-Student p< 0,621 ambos não significantes. As principais complicações foram a infecção local em 5 (11,9%) pacientes e a fístula orocutânea em 4 (9,5%). Houve uma fratura da placa de titânio, dois pacientes evoluíram com osteorradionecrose e nove com disfunção da articulação têmporo-mandibular. CONCLUSÕES: Não houve diferenças estatisticamente significantes entre os grupos de ressecção marginal e segmentar nos critérios analisados. Portanto, a conservação do ramo ascendente da mandíbula, em lesões que não apresentem envolvimento mandibular, mesmo avançadas, não aumenta o índice de recidiva. / INTRODUCTION: For several decades, resection of the ascending ramus of the mandible was considered to be mandatory for the treatment of tonsil and retromolar trigone tumours, independent from the damage degree of the mandibular bone, causing considerable functional and aesthetic deficit, many times with irreparable quality of life loss, sometimes unnecessary. Thus, marginal resection of the mandibular bone appeared as a feasible alternative treatment, since maintaining a segment of the mandibular ramus in lesions without bone involvement did not increase the recurrence indexes or compromise the principles of oncological radicalness. OBJECTIVES AND METHODS: Through a retrospective study from October 1994 to December 2001, 42 patients with advanced retromolar and tonsil tumors were compared, 20 undergoing marginal resection of the mandibular bone and 22 undergoing segmental resection of the ascending ramus of the mandible, with regard complications, injury originated from the procedure, locoregional recurrence and survival. RESULTS: From the 20 patients undergoing to marginal mandibulectomy, assessed for a period of 09 to 60 months, seven (35%) patients died of the disease, with a minimal survival of 9 months: 3 due to local recurrence, 3 due to regional recurrence and 1 due to local and regional recurrence. One patient died in the immediate postoperative period. When assessing the surgical part, all the margins were found to be free and in two patients, were considered to be of little depth, one of them being found in one of the patients that died from local recurrence. There was lymph nodal dissemination in 15 patients, with capsular rupture in 4, of which two presented regional recurrence. The locoregional control was obtained in 63% of the patients. From the 22 patients undergoing to segmental resection of the mandibular bone, with a follow-up varying from 14 to 60 months, 8 (36.4%) died of the disease, with a minimum survival of 9 months, 5 due to local recurrence and 3 due to distant recurrence. One patient died in the immediate postoperative period. The surgical margins were considered free from disease in 20 patients and, in three they were too small, one patient died of local recurrence. There was lymph nodal dissemination in 12 patients, and 7 presented capsular rupture. The locoregional control was obtained in 61% of the patients. In the survival analysis curve, by the Kaplan-Meier method, the group submitted to marginal mandibulectomy presented with a rate of 42%, with an interval of 31 to 52 months, standard error of 5 months and confidence interval of 95%, and the group submitted to segmentary resection, 38% with an interval of 27 to 48 months, a standard error of 5 months, and a confidence interval of 95%. The comparison using the non-parametric Log-Rank test presented p<0.8326 and the t-Student test p< 0.621, both not statistically significant. The main complications were local infection in 5 (11.9%) patients and oro-cutaneous fistula in 4 (9.5%). There was one titanium plate fracture, two patients developed osteoradionecrosis and nine temporo-mandibular dysfunction. CONCLUSIONS: There weren t statistically significant differences between the marginal and the segmental resection groups in relation to the analyzed criteria. So, the preservation of the ascending ramus of the mandible, in lesions which do not present mandible commitment, even if not advanced, doesn t increase the recurrence rate.

Carcinoma de Células Renais (CCR) representa uma família de tumores distintos com evolução clínica imprevisível. Uma variedade de moléculas tem sido avaliada como marcadores prognósticos para CCR. Ciclina D1, uma proteína reguladora do ciclo celular, encontra-se superexpressa em vários tumores primários. Nosso objetivo é avaliar sua expressão como marcador prognóstico em CCR. Antes disso, traçamos um perfil clínico e histopatológico da amostra e verificamos sua relação com os fatores prognósticos considerados clássicos pela literatura. 109 espécimes de pacientes diagnosticados com CCR foram obtidos entre 2005 e 2010 no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto USP e submetidos à análise imunoistoquímica juntamente com 07 amostras de tecido renal normal. A maior parte das características epidemiológicas e clínicas de nossa amostra foi similar àquelas descritas na literatura mundial. Houve predomínio do gênero masculino, da raça branca, com idade próxima a 60 anos, frequência de pacientes assintomáticos em torno de 36% e grande prevalência do CCR de células claras (71,55%). A mortalidade específica da doença foi de 13,76%, sendo o CCR de células claras o tipo mais frequente entre os óbitos e casos metastáticos. Os casos que exibiram má evolução clínica, definida pela ocorrência de metástase e/ou óbito por CCR (22,01%), estiveram associados à presença de sintomas ao diagnóstico, maior tamanho tumoral, grupo de estágio alto (III ou IV), grau nuclear de Fuhrman alto (3 ou 4), presença de necrose e de diferenciação sarcomatóide no tumor, além de outros fatores histológicos desfavoráveis (p < 0,01). Isso indica que as variáveis utilizadas na avaliação de prognóstico em países desenvolvidos podem ser aplicadas aos nossos pacientes. Não houve expressão imunoistoquímica de Ciclina D1 nos casos de tecido renal normal. Observou-se heterogeneidade de marcação nuclear intratumoral no total de casos e menor expressão proteica entre os CCR papilífero e cromófobo. Pacientes com tumores com Ciclina D1baixa (até 30% de células positivas) apresentaram má evolução clínica (p = 0,03), maior tamanho tumoral (p = 0,01), presença de sintomas ao diagnóstico (p = 0,04), grau nuclear alto (p = 0,001), presença de necrose (p = 0,004) e de diferenciação sarcomatóide (p = 0,04) no tumor, além de menor sobrevida sem metástase e/ou óbito por CCR (p = 0,03). Após análise multivariada, a expressão de Ciclina D1 não apresentou valor prognóstico independente para má evolução clínica, embora tenha aumentado levemente a acurácia prognóstica do modelo adotado. Em todas as análises realizadas para o CCR de células claras isoladamente, observamos significância estatística semelhante à do total de casos (CCR). Nosso estudo demonstrou que: a proteína Ciclina D1 encontra-se superexpressa em CCR; os tipos de CCR parecem exibir diferentes padrões de marcação imunoistoquímica da Ciclina D1; alta marcação da proteína (acima de 30% de células positivas) esteve associada à boa evolução clínica e à maioria dos fatores prognósticos favoráveis bem estabelecidos na literatura. Novas investigações são necessárias para descobrir que mecanismos levam a seu acúmulo nas células neoplásicas e quais outros eventos podem estar contribuindo para a progressão da doença. / Renal Cell Carcinoma (RCC) is a family of distinct tumors with unpredictable clinical outcome. A variety of molecules have been evaluated as prognostic markers for RCC. Cyclin D1, a cell cycle regulatory protein, is overexpressed in several primary tumors. Our purpose is to evaluate its expression as a prognostic marker in RCC. Before that, we drew a clinical and histopathological profile of the sample and verified its relationship with prognostic factors regarded as classics in literature. 109 specimens from patients diagnosed with RCC were obtained between 2005 and 2010 at Hospital das Clínicas - Ribeirão Preto School of Medicine USP and submitted to immunohistochemical analysis, along with 07 normal kidney tissue samples. Most epidemiological and clinical characteristics of our sample were similar to those described in the literature. There was a predominance of male, Caucasian, aged about 60 years, the frequency of asymptomatic patients around 36%, and high prevalence of clear cell RCC (71.55%). The disease-specific mortality was 13.76%, being the clear cell RCC the most frequent type among deaths and metastatic cases. Cases that exhibited poor clinical outcome, defined by the occurrence of metastasis and/or death by RCC (22.01%), were related to the presence of symptoms at diagnosis, larger tumor size, high stage group (III or IV), high Fuhrman nuclear grade (3 or 4), presence of necrosis and sarcomatoid differentiation in the tumor and other unfavorable histological factors (p < 0.01). This indicates that the variables used in the assessment of prognosis in developed countries can be applied to our patients. There was no immunohistochemical expression of Cyclin D1 in cases of normal kidney tissue. There was intratumoral heterogeneity in nuclear staining in all cases and lower protein expression among papillary and chromophobe RCC. Patients with Cyclin D1low tumors (up to 30% positive cells) showed poor clinical outcome (p = 0.03), larger tumor size (p = 0.01), presence of symptoms at diagnosis (p = 0.04), high nuclear grade (p = 0.001), presence of necrosis (p = 0.004) and sarcomatoid differentiation (p = 0.04) in the tumor and lower survival without metastasis and/or death by RCC (p = 0.03). After multivariate analysis, the expression of Cyclin D1 showed no independent prognostic value for poor clinical outcome, although it has slightly increased the prognostic accuracy of the model adopted. In all analyzes performed for clear cell RCC alone, we observed statistical significance similar to that of the total cases (RCC). Our study showed that: Cyclin D1 protein is overexpressed in RCC; RCC types seem to exhibit different patterns of immunohistochemical staining for Cyclin D1; high protein expression (over 30% positive cells) was related to good clinical outcome and to most favorable prognostic factors well established in the literature. Further investigations are necessary to reveal which mechanisms lead to its accumulation in neoplastic cells and what other events might be contributing to the progression of the disease.

Genetic changes are hallmarks of cancer development involving the activation and/or inactivation of oncogenes and tumour suppressor genes, respectively. In non-melanoma skin cancer (NMSC) development, the initiation of genetic mutations results from exposure to solar ultraviolet radiation. Non-melanoma skin cancers are comprised of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Several related cutaneous lesions also exist, of which solar keratoses (SK) are widely accepted as a precursor dysplasia to SCC development. The study of recurrent genetic changes present within NMSC and SK should help reveal causative mutations in skin cancer development. Such analysis could also elucidate links in the genetic similarity of these dysplasia. The rapid screening of numerical changes in DNA sequence copy number throughout the entire genome has been made possible by the advent of comparative genomic hybridisation (CGH). This technique enables the identification of net gains and loss of genetic material within a tumour DNA sample. Chromosomal regions of recurrent gain or loss identify loci containing putative oncogenes and tumour suppressor genes, respectively with potential roles in NMSC tumourigenesis. Used in conjunction with tissue microdissection and universal degenerate PCR techniques this can enable the elucidation of aberrations in small histologically distinct regions of tumour. Such a technique can utilize archival material such as paraffin embedded tissue, which is the major source of neoplastic material available for cancer research. This study used the CGH technique to investigate aberrations in BCC, SCC and SK samples. The screening of copy number abnormalities (CNAs) in BCC revealed that although these tumours were close to diploid and generally genetically stable, they did contain several recurrent aberrations. The loss of genetic material at 9q was identified in a third of BCC tumours studied. This is characteristic of inactivation of the PTCH tumour suppressor gene, a known attribute in some sporadic BCC development. Validation of this loss was performed via loss of heterozygosity, demonstrating good concordance with the CGH data. In addition the over-representation of the 6p chromosome arm was revealed in 47% of biopsies. This novel CNA is also commonly observed in other cutaneous neoplasias, including Merkel cell carcinoma and malignant melanoma. This suggests a possible common mechanism in development and or promotion in these cutaneous dysplasias, the mechanisms of which have yet to be clearly defined. In contrast to BCC, numerical genetic aberrations in SCC and SK were much more frequent. Several regions of recurrent gain were commonly shared between both dysplasias including gain of 3q, 4p, 5p, 8q, 9q, 14q, 17p, 17q and 20q. Common chromosomal regions of loss included 3p, 8p, 9p, 11p, 13q and 17p. In addition loss of chromosome 18 was significantly observed in SCC in comparison to SK, a possible defining event in SK progression to SCC. The identification of shared genetic aberrations suggests a clonal and genetic relationship between the two lesions. This information further supports the notion for re-classification of SK to an SCC in situ or superficial SCC. Finally, the CNAs detected have been similarly observed in other squamous cell-derived tumours, for example cervical and head and neck SCC. This provides further evidence to common mechanisms involved in the initiation, development and progression of SCC neoplasia. This study has identified a number of recurrent chromosomal regions, some of which are novel in NMSC development. The further delineation of these loci should provide additional evidence of their significance and degree of involvement in NMSC tumourigenesis. The identification of the cancer-causing genes mapped to these loci will further demarcate the genetic mechanisms of BCC and SCC progression. An understanding of the events involved in skin cancer formation and progression should shed additional light on molecular targets for diagnostics, management and therapeutic treatment.

Non-melanoma skin cancer (NMSC), comprised of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is the most common cancer in Caucasians. Ultraviolet radiation (UVR) exposure is the most important environmental risk factor for both BCC and SCC development. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type. It has been hypothesized that intermittent patterns and childhood sunlight exposure are important for BCC while continuous (chronic) and lifelong (i.e. childhood and adulthood) sunlight exposure is important for SCC. Epidemiologic studies have demonstrated that cutaneous human papillomavirus (HPV) infection may also be a risk factor for developing NMSC. However, the pathway by which cutaneous HPV is associated with NMSC remains unclear. It is hypothesized that UVR exposure may interact synergistically with cutaneous HPV in NMSC development. The goal of the research study was to evaluate the relationship between levels of sunlight exposure and BCC and SCC and to investigate differences in sunlight-associated BCC and SCC risk by genus-specific cutaneous HPV serostatus. To address these goals, we conducted a clinic based case-control study of histologically confirmed BCC and SCC cases recruited from a university dermatology clinic and controls with no history of cancer and screened negative for current skin cancer. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the associations between measures of sunlight exposure and BCC and SCC. Multiplicative interactions were tested by placing an interaction term for the product of genus-specific HPV seroreactivity and sunlight related factors in the logistic regression models. Measures of both intermittent and continuous patterns of sunlight exposure were associated with both types of skin cancer (i.e. BCC and SCC). Specifically, history of blistering sunburn (a marker of intermittent sunlight exposure) and occupational sunlight exposure (i.e. having a job in the sun for at least 3 months for >10 years) were both associated with BCC and SCC. The major differences in patterns of sunlight exposure between BCC and SCC were observed for sunlight exposure in one's thirties. Additionally, sunlight exposure in one's twenties was associated with SCC, regardless of pattern of exposure; similar associations were not observed for BCC. Measures of timing of sunlight exposure consistently demonstrated that childhood/adolescent sunlight exposure was more important for SCC than BCC. These included number of moles on the forearms and entire body (measure of increased childhood sunlight exposure), and younger age at first and tanning bed use. Younger age at first blistering sunburn was statistically significantly associated with both BCC and SCC. NMSC cases were more likely to be seropositive for cutaneous HPV antibodies compared to controls. Compared to tanning, having a propensity to sun burn (p=0.006), or poor tanning ability (p=0.003) were significantly associated with a higher seroprevalence to genus beta HPV types within SCC cases. Statistically significant interactions were observed between poor tanning ability and genus-specific seropositivity with NMSC. Specifically, the associations between poor tanning ability and BCC (p interaction=0.02) and SCC (p interaction=0.01) were significantly stronger among individuals that were seropositive for antibodies to genus alpha HPV types. Similarly, the association between poor tanning ability and SCC was stronger among those seropositive for genus beta HPV types (p interaction=0.001). No additional significant interactions were observed for BCC or SCC between cutaneous sensitivity, history of blistering sunburn, or cumulative sunlight exposure and genus-specific seroreactivity. In conclusion, associations with patterns of sunlight exposure appeared to be similar between BCC and SCC cases. With the exception of age at first blistering sunburn, factors measuring timing of sunlight exposure demonstrated stronger and statistically significant relationships with SCC. Additionally, of the sunlight related factors measured, only the associations between poor tanning ability and BCC and SCC were significantly modified by HPV seropositivity to types in genera alpha or beta.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-29T08:31:16Z No. of bitstreams: 2 Dissertação - Carlos Henrique Pereira - 2014.pdf: 3850945 bytes, checksum: 985b041e7a863070b3fa0562180a40f3 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-29T08:33:08Z (GMT) No. of bitstreams: 2 Dissertação - Carlos Henrique Pereira - 2014.pdf: 3850945 bytes, checksum: 985b041e7a863070b3fa0562180a40f3 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-01-29T08:33:08Z (GMT). No. of bitstreams: 2 Dissertação - Carlos Henrique Pereira - 2014.pdf: 3850945 bytes, checksum: 985b041e7a863070b3fa0562180a40f3 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-07-07 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Objective: Investigate, on a comparative basis, the expression of the adhesion molecules E-cadherin (E-cad), β-catenin (β-cat) and the proliferation index (Ki-67) at the invasive tumor front (ITF) in Squamous Cell Carcinoma (SCC) and basaloid squamous cell carcinoma (BSCC). Material and Methods: Thirty-five SCC and 16 BSCC cases were evaluated by immunohistochemistry. Clinico-pathological data and survival data were evaluated and compared. Results: There was a low expression of E-cad in the cytoplasmic membrane (p = 0.50) as well as in the nucleus (p = 0.31) for both SCC and BSCC. A high expression of E-cad was seen in the cytoplasm for the SCC group (80%) when compared to the BSCC group (25%) (p<0.01). The expression of β-cat in the cytoplasmic membrane (p = 0.28) and in the cytoplasm (p = 0.44) was low in both SCC and BSCC groups. Both types of carcinoma presented low expressions of β-cat in the nucleus (p = 0.03). The Ki-67 expression was low irrespective of tumor variant. The high expression of E-cad in the cytoplasm was associated with T3/T4 tumors (p = 0.04) in the SCC group and there was no significant association of E-cad, β-cat, Ki-67 with the other clinical variables. In terms of disease-free survival and overall survival, there were no significant differences between SCC and BSCC. Conclusion: The E-cad-β-cat system was found to be dysregulated in both oral SCC and oral BSCC. The Ki-67 cell proliferation index was extremely low in the cases investigated and consequently had no prognostic value. / Objetivo: Investigar comparativamente a expressão das moléculas de adesão E-caderina (E-cad), β-catenina (β-cat) e o índice de proliferação (Ki-67) em Carcinoma Espinocelular (CEC) e Carcinoma escamoso basalóide (CEB). Material e Métodos: Nesse estudo, foram selecionados 35 casos de CEC e 16 casos de CEB e investigados por meio de técnica imuno-histoquímica. A associação das variáveis clinico-patológicas e dados de sobrevida foram avaliados. Resultados: Ambos os grupos tiveram baixa expressão de E-cad em membrana citoplasmática (p=0,50) e núcleo (p=0,31), essa associação não foi estatisticamente significante entre os grupos. Alta expressão de E-cad no citoplasma foi notada no grupo CEC (80%) quando comparado ao grupo CEB (25%), p<0,01. A expressão de β-cat em membrana citoplasmática (p=0,28) e citoplasma (p=0,44) foram baixos em CEC e CEB. Ambos os grupos tiveram baixa expressão de β-cat em núcleo, p=0,03. Não houve diferença estatisticamente significante quanto à expressão de Ki-67 entre os grupos. Alta expressão de E-cad em citoplasma foi associada a tumores T3/T4 (p=0,04) no grupo CEC. Pacientes estilistas apresentaram baixa expressão de β-cat em membrana citoplasmática (p=0,05). Não houve associação entre a expressão de E-cad, β-cat e Ki-67 com as demais variáveis clínicas dos grupos. A sobrevida livre de doença e a sobrevida global não foram estatisticamente significantes na associação entre os grupos CEC e CEB. Conclusão: O sistema E-cad-β-cat encontra-se desregulado tanto nos de CEC quanto nos de CEB de cavidade oral, levando as células epiteliais a perderem o seu fenótipo e promovendo a invasão e progressão tumoral. O índice de Ki-67 foi extremamente baixo não tendo valor prognóstico nos casos avaliados.