Microsystems are a broad category of engineered technologies in the micro and nano scale that have a diverse range of applications. They are emerging as a powerful tool in the field of biomedical research, drug discovery, as well as clinical diagnostics and prognostics, especially with regards to cancer. One of the major challenges in precision and personalized medicine in cancer lies in the technical difficulties of ex-vivo cell culture and propagation of the limited number of primary cells derived from patients. Therefore, our aims are to 1. Develop a biologically relevant platform for culturing cancer cells and characterize how it influences the cell growth and phenotype compared to conventional 2-dimensional(2D) cell culturing techniques, 2. Isolate secondary metabolites from endophytic fungi and screen them on the platform for potential anticancer properties in a preliminary drug discovery pipeline, 3. Design and develop biosensors for quantifying cell responses in real-time within these systems. Several biomaterial scaffolds with microscale architectures have been utilized for engineering the tumor extracellular matrix, but very few studies have thoroughly characterized the phenotypic changes in their cell models, which is critical for translational applications of biomaterial systems. The overall objective of these studies is to engineer a biomimetic platform for the culture of breast cancer cells in vitro and to quantify and profile their phenotypic changes. In order to do this, we first evaluated a blank-slate matrix consisting of thiolated collagen, hyaluronic acid and heparin, cross-linked chemically via Michael addition reaction using diacrylate functionalized poly (ethylene glycol). The hydrogel network was used with triple-negative breast cancer cells and showed significant changes in characteristics, with cells self-assembling to form a 3D spheroid morphology, with higher viability, and exhibiting significantly lower cell death upon chemotherapy treatment, as well as had a decrease in proliferation. Furthemore, the transcriptomic changes quantified using RNA-Seq and Next-Gen Sequencing showed the dramatic changes in some of the commonly targeted pathways in cancer therapy. Furthermore, we were able to show the importance of our biomimetic platform in the process of drug discovery using fungal endophytes and their secondary metabolites as the source for potential anticancer molecules. Additionally, we developed gold nanoparticle and antibody-based (ICAM1 and CD11b) sensors to quantify cell responses spatiotemporally on our platform. We were able to show quenching of the green fluorescent fluorophores due to the Förster Resonance Energy Transfer mechanism between the fluorophore and the gold nanometal surface. We also observed antigen-dependent recovery of fluorescence and inhibition of energy transfer upon the antibody binding to the cell-surface receptors. Future efforts are directed towards incorporating the hydrogel system with antigen-dependent sensors in a conceptually-designed microfluidic platform to spatiotemporally quantify the expression of surface proteins in various cells of the tumor stroma. This includes the migration,infiltration, and polarization of specific immune cells. This approach will provide further insight into the heterogeneity of cells at the single-cell resolution in defined spaces within the 3D microfluidic platform. / Doctor of Philosophy / Microsystems are a broad category of engineered technologies in the micro and nano scale that have a diverse range of applications. They are emerging as a powerful tool in the field of biomedical research, drug discovery, as well as clinical diagnostics and prognostics, especially with regards to cancer. However, a major challenge in being able to offer personalized medicine to cancer patients comes from the difficulty of growing cells from the patient's tumor biopsy in a laboratory for further screening and analysis. There are also limited resources available for real-time expression of proteins on cell-surfaces, that could be potential biomarkers and targets for treatment. Various natural and synthetic polymers are biocompatible and have been used widely in engineering the tumor extracellular matrix. However, the effect of hydrogels derived from these polymers on the specific tumor cells are not always well characterized. Our studies explore the influence of a biohybrid hydrogel on breast cancer cells and our results show that the microscale architecture of the hydrogel platform works as a suitable scaffold for recapitulating the 3-dimensional(3D) breast tumor microenvironment, and can also be employed in the drug discovery process. Additionally, we developed a nano-scale biosensor to enable the quantification of specific cell-surface proteins in real-time. Ongoing and future efforts are focused on designing and fabricating a microfluidic device with precise control over the design of space and special chambers for cell culture. These will be used for studying interactions of various cells in the tumor microenvironment that influence cancer progression. Integrating these micro-scale systems, including sensors will allow researchers to quantify cell behavior in response to the variable factors they are exposed to, as well as provide insight to answer fundamental questions about cancer biology that are limited by the conventional 2D cell culture systems.

Flera av de senaste forskningsstudierna har visat att tumörmikromiljö är mycket viktigare än man hittills trott. Ett av de viktigaste elementen i tumörmikromiljön är immunceller som producerar olika kemokiner samt uttrycker specifika receptorer. Kemokiner kan både aktivera och hämma immunförsvaret. Syftet med denna pilotstudie var att undersöka uttryck av kemokinreceptor CCR5 hos patienter med koloncancer (n=41) och utvärdera prognostisk betydelse genom att undersöka uttrycksskillnader mellan tumör och parad tumörfri vävnad med hjälp av immunhistokemisk detektionsmetod. Syftet var även att identifiera sambandet med kön, ålder, tumörstadier (TNM) och lokalisation av primär tumör. Resultaten visade signifikanta skillnader i uttryck av CCR5 mellan koloncancer och parad tumörfri kolonvävnad (p<0,001). Nivån av CCR5 uttryck var 79% högre i tumörvävnad jämfört med parad tumörfri vävnad. Inga statistiskt signifikanta skillnader eller korrelationer mellan CCR5 uttryck och tumörstadier, kön, ålder eller tumörlokalisation på patienterna hittades. Däremot resultaten tyder på att det föreligger samband mellan patienternas ålder och tumörlokalisation. Sammanfattningsvis bekräftar studieresultaten att CCR5 kan vara involverad i patogenesen av koloncancer. / The latest research has shown that the cancer microenvironment is much more important than previously thought. One of the most important elements in it are immune cells that produce various chemokines and express specific receptors. Chemokines can both activate and inhibit the immune system. The aim of this pilot study was to investigate the expression of chemokine receptor CCR5 in patients with colon cancer (n=41) and evaluate prognostic significance by identifying expressional differences between tumor and paired tumor-free tissue using immunohistochemical method. The aim was also to identify the relationship with the clinical parameters: gender, age, tumor stages (TNM) and location of primary tumor. Results showed significant differences in CCR5 expression between colon cancer and paired tumor-free colon tissue (p<0,001). The level of CCR5 expression was 79% higher in tumor tissue compared to paired tumor-free tissue. No statistically significant differences or correlations between CCR5 expression and tumor stages, gender, age, or tumor location were found. However, the results indicate that there is a relationship between the patients' age and tumor localization. In summary, the results of the study confirm that CCR5 may be involved in the pathogenesis of colon cancer.

A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Histopathologic examination of the tumor microenvironment demonstrates the presence of a vast repertoire of infiltrating lymphocytes and antigen presenting cells (APC’s). Recent studies establish a strong correlation between the tumor microenvironment cell composition and prognostic value in terms of cell type, location and ratio, referred to as a tumor’s immunoscore. More specifically, the relationship between T regulatory (Treg) cell to T effector (Teff) cell percentage predominates as a mechanism of tumor immune evasion. Further investigation of the factors influencing the development of Treg and Teff cells is therefore warranted. Gammainterferon‐inducible lysosomal thiol reductase (GILT) acts to influence antigenic processing and presentation by MHC class II cells, ultimately impacting lymphocyte development. Evaluation of the role of GILT expression in MHC class II+ APC’s with respect to Treg and Teff cell development in primary melanoma lesions, to our knowledge, has not been reported. Therefore our investigation focuses on elucidating a plausible relationship between GILT presence and Treg to Teff cell ratio. The aim of our study is to examine a possible association between GILT expression in APC’s and Treg:Teff cell ratio. We hypothesized GILT expression in melanoma cells would result in a decreased Treg to Teff ratio or an enhanced T cell‐mediated response. Our study included 17 de‐identified primary melanoma specimens previously stained and scored for Treg, Teff, CD8, MHC class II and GILT. Scoring was performed through identification of four areas per specimen with highest Treg and Teff cell density. These four areas were then averaged with ± standard deviation (SD). With use of landmark association, these four areas were identified and scored for MHC class II and GILT in APC’s and tumor cells with consideration to presence/absence, intensity and frequency of staining. Statistical significance was not reached relative to our hypothesized relationship of a decreased Treg to Teff cell ratio in the presence of GILT+ MHC class II. Similarly, we did not reach statistical significance when comparing individual cell types to GILT, MHC class II and GILT + MHC class. In our study, we were unable reach statistical significance relative to our proposed correlation between MHC class II and GILT presence leading to a decreased Treg to Teff cell ratio or enhanced T‐cell mediated immune response. A major limitation of our study included the small sample size leading to a probable type II error, prompting the need for further investigation of the factors influencing the Treg to Teff cell ratio within the melanoma tumor microenvironment on a larger scale.

INTRODUÇÃO: O carcinoma ductal in situ da mama é o estágio final antes do carcinoma ductal invasivo (CDI) no processo de carcinogênese mamária. As semelhanças histológicas, moleculares e imunoistoquímicas do epitélio nestas duas lesões tornaram improvável que o epitélio fosse o único responsável pelo processo de invasão estromal. Ao mesmo tempo, foram identificadas importantes alterações nas características do microambiente mamário durante esta transição. As células mioepiteliais, componente do microambiente e cuja rotura determina o diagnóstico histológico do carcinoma invasivo, tem papel direto ou indireto neste processo. A fim de predizer esse risco de invasão, propomos que as características das células mioepiteliais sejam investigadas em conjunto com as características intrínsecas do epitélio neoplásico. OBJETIVOS: Determinar os fatores morfológicos e moleculares das células epiteliais e os marcadores das células mioepiteliais do microambiente em carcinomas ductais in situ da mama relacionados ao risco de invasão estromal. MÉTODOS: Foram selecionados retrospectivamente 236 casos consecutivos com diagnóstico inicial de CDIS seguidos de ressecção cirúrgica na Divisão de Anatomia Patológica da Faculdade de Medicina da Universidade de São Paulo no período de janeiro de 2000 a dezembro de 2009, divididos nos grupos 1 (CDIS puro, 90 casos) e 2 (CDIS associado a carcinoma invasor, 146 casos). Blocos de microarranjos de tecido foram construídos com áreas representativas dos CDIS e CDI que foram, então, classificados nos perfis moleculares de acordo com o seu perfil imunoistoquímico. Os marcadores mioepiteliais (vimentina, AML, calponina, p63, CK5/6, SMMHC, CD10) foram avaliados de acordo com a expressão imunoistoquímica baixa ou alta. RESULTADOS: Os perfis moleculares dos componentes in situ e invasivo da mesma lesão foram semelhantes. Os CDIS de baixo grau histológico, em comparação aos CDIS de alto grau, apresentaram maior número de casos com perfil molecular luminal (143 vs. 18) e menor proporção de casos luminal/HER2-positivo (6 vs. 11), HER2 (4 vs. 27) e triplo-negativo (3 vs. 22). Os CDIS no grupo 1, em relação aos CDIS no grupo 2, tiveram maior proporção de casos com expressão de receptores hormonais (84.4% vs. 71,2%) menor expressão de HER2 (76,7% vs. 81,5%), mais perfis moleculares luminal/HER2-positivo (12,2% vs. 4,1%) e menos perfis triplo-negativos (4,4% vs. 14,4%). A expressão de CK5/6 nas células epiteliais do CDIS teve maior proporção entre o subtipo HER2 (34,5%), seguido pelo triplo-negativo (25%), luminal/HER2- negativo (15,4%) e luminal/HER2-positivo (12,5%). A expressão de CK5/6 foi maior nas células epiteliais dos CDIS do grupo 1 em relação aos CDIS do grupo 2 (30,6% vs. 11,3%). A expressão alta de SMMHC nas células mioepiteliais associou-se mais frequentemente aos CDIS do grupo 1 (88,2%) em relação aos CDIS do grupo 2 (11,8%), e esta diferença manteve-se tanto nos CDIS de baixo grau (85,7%) quanto nos de alto grau histológico (92,3%). A expressão baixa de CD10 nas células mioepiteliais associou-se mais frequentemente aos CDIS do grupo 2 (95,6%) em relação aos CDIS do grupo 1 (4,4%), e esta diferença manteve-se tanto nos CDIS de baixo grau (96,4%) quanto nos de alto grau histológico (94,1%). Não houve diferença na expressão de marcadores mioepiteliais de acordo com o perfil molecular baseado na imunoistoquímica. CONCLUSÕES: O risco de invasão estromal em CDIS está associado ao perfil molecular triplo-negativo e à perda de expressão do marcador CD10 pelas células mioepiteliais e é inversamente proporcional à expressão de CK5/6 pelas células neoplásicas e à forte expressão do marcador SMMHC nas células mioepiteliais / INTRODUCTION: Ductal carcinoma in situ is the last step preceding invasive ductal carcinoma in breast carcinogenesis. Histologic, molecular and immunohistochemistry similarities in epithelium of these components make improbable that epithelial changes are sole responsible for the stromal invasion. At the same time important changes were identified in mammary microenvironment during this transition. Myoepithelial cells, components of microenvironment and which rupture is the histological definition of stromal invasion, have a direct or indirect role in this process. We propose an associated investigation of myoepithelial cells and intrinsic neoplastic epithelium caracteristics in view of predict the risk of stromal invasion. OBJECTIVES: To determinate morphologic and molecular factors of epithelial cells and microenvironment myoepithelial cell markers related to stromal invasion risk in ductal carcinomas in situ of the breast. METHODS: 236 cases with initial diagnosis of DCIS followed by surgical ressection were retrospectively selected from Division of Surgical Pathology, Faculty of Medicine, Sao Paulo University from january 2000 to december 2009, divided in groups 1 (pure DCIS, 90 cases) and 2 (DCIS associated with invasive carcinoma, 146 cases). Tissue microarrays were constructed with selected areas of DCIS and IDC and those were then classificated in molecular subgroups according to its immunohistochemistry profile. Myoepithelial markers (vimentin, smooth muscle actin, calponin, p63, CK5/6, SMMHC, CD10) were avaliated according to its high or low immunohistochemistry expression. RESULTS: Molecular profiles of in situ and invasive components of the same tumor were similar. Low-grade DCIS showed more luminal profiles than highgrade DCIS (143 vs. 18), and less luminal/HER2-positive (6 vs. 11), HER2 (4 vs. 27) and triple-negative (3 vs. 22) profiles. Group 1 DCIS, compared to group 2 DCIS, showed more cases with hormonal receptor expression (84.4% vs. 71.2%), less expression of HER2 (76.7% vs. 81.5%), more luminal/HER2-positive (12.2% vs. 4.1%) and less triple-negative profiles (4.4% vs. 14.4%). CK5/6 expression in epithelial cells was more frequent in HER2 (34.5%) subtype followed by triple-negative (25%), luminal/HER2-negative (15.4%) and luminal/HER2-positive (12.5%). Epithelial cells in group 1 DCIS showed more CK5/6 expression than cells in group 2 DCIS (30.6% vs. 11.3%). High expression of SMMHC in myoepithelial cells was more frequent in group 1 DCIS (88.2%) than group 2 DCIS (11.8%) and this pattern was also mantained in low-grade DCIS (85.7%) and high-grade DCIS (92.3%). Low expression of CD10 in myoepithelial cells was more frequent in group 2 DCIS (95.6%) than group 1 DCIS (4.4%) and this pattern was also mantained in low-grade (96.4%) and high-grade DCIS (94.1%). There was no significant difference in expression of myoepithelial cells according to molecular profile classified by immunohistochemistry. CONCLUSIONS: Stromal invasion risk in DCIS is associated with triple-negative profile, CD10 expression loss in myoepithelial cells and inversely correlated with CK5/6 expression in neoplastic cells and high expression of SMMHC in myoepithelial cells

O osteossarcoma é um tumor ósseo maligno, de maior ocorrência em cães, possui rápido crescimento e alto potencial metastático. Assim, o cão é um modelo útil para o estudo da doença em humanos, tendo em vista as semelhanças clínicas e histopatológicas que ocorrem em ambas às espécies. Atualmente, os estudos a respeito de células-tronco são promissores considerando seu alto potencial terapêutico. Entretanto, ainda prevalecem muitas dúvidas referentes ao tratamento de tumores utilizando a terapia celular. Este tema é pouco conhecido e estudado, por isso, o objetivo deste trabalho foi avaliar a interação entre células-tronco obtidas da polpa dentária canina com as células derivadas osteossarcoma canino. Foram realizados cocultivos celulares das células derivadas de polpa dentária canina, osteossarcoma canino e derivadas de osso normal canino. Analisou-se os aspectos morfológicos das células cocultivadas e controle, assim como a atividade proliferativa, a morte celular, o potencial elétrico mitocondrial e a expressão gênica. A partir dos resultados obtidos, concluiu-se que a interação entre a célula-tronco da polpa dentária canina imatura e as células de osteosarcoma canino não apresentam alterações morfológicas. Entretanto, as células-tronco derivadas da polpa dentária canina e de osso fetal canino sadio parecem servir de suporte para o crescimento tumoral. Além disso, a cocultura celular, em todos os grupos testados, promove alterações na expressão gênica e proteica. / Osteosarcoma is a malignant bone tumor most frequent in dogs. It has fast growth and high metastatic potential. Thus, the dog is an useful model for the study of human disease, due to the clinical and histological similarities found in both species. Currently, studies about stem cells are promising considering its high therapeutic potential. However, many doubts still exist regarding the treatment of tumors using cell therapy. This theme is little known and studied. Therefore, the aim of this study was to evaluate the interaction between stem cells obtained from canine immature dental pulpstem cells with osteosarcoma cells derived from dogs. Cellular coculture were performed using cells derived from canine dental pulp, canine osteosarcoma and canine normal bone. The morphological aspects of cocultured cells and control were analyzed, as well as proliferative activity, cell death, the mitochondrial membrane electric potential and gene expression. In summary, it was concluded that the interaction between stem cells from canine immature dental pulp and canine osteosarcoma cells did not show morphological changes. However, stem cells derived from canine dental pulp and healthy canine fetal bone serve to support tumor growth. Furthermore, the cell coculture in all groups tested, causes changes in gene and protein expression.

Le carcinome épidermoïde cutané (CEC) est l'un des cancers les plus fréquents et il est résistant aux traitements chimiothérapeutiques classiques. De nombreuses études montrent que selon leur phénotype les cellules du microenvironnement inflammatoire peuvent inhiber (cellules Th1/M1) ou favoriser (cellules Th2/M2) le développement tumoral. En fonction des cytokines présentes dans ce microenvironnement, il est possible de reprogrammer les cellules immunitaires et de les rendre moins permissives au développement tumoral. L’onconstatine M (OSM) est une cytokine aux effets pléiotropes, elle peut favoriser la prolifération, l’invasion tumorale des cellules tumorales et induire une polarisation immunitaire Th2/M2. Nous avons montré que l'OSM a des effets pro-inflammatoires au niveau cutané et qu’elle module le phénotype des kératinocytes normaux mais son rôle dans les CEC n’est pas décrit. Nous avons donc étudié l’implication de l'OSM dans le développement des CEC. Nous avons montré que l'OSM était surexprimée dans les CEC humains ainsi que d'autres cytokines comme l'IL-6, l'IL-1β, l'IFNγ suggérant une polarisation Th1/M1 des cellules du microenvironnement. In vitro, l'OSM induit l’activation de voies de signalisation pro-tumorales (STAT3 - ERK) au niveau de kératinocytes murins malins ainsi que leur prolifération et leur migration. La greffe de ces cellules chez la souris entraine le développement de CEC associés à une surexpression d'OSM. Enfin, l’absence d'OSM entraine une diminution du volume tumoral de 30% et à une réduction de la polarisation M2. Collectivement, ces résultats suggèrent un rôle pro-tumoral de l'OSM dans le développement des CEC et le blocage de cette cytokine pourrait constituer une nouvelle alternative thérapeutique. / Cutaneous squamous cell carcinoma (cSCC) is one of the most frequent keratinocyte malignancies worldwide and is chemotherapy resistant. Surgery is the curative treatment but there isn’t any alternative in advanced cSCC. Reprogramming tumor microenvironment and tumor immunosuppressive mechanisms is a new therapeutic approach. Indeed, depending on cytokine expressed in tumor microenvironment, immune cells can inhibit (Th1/M1 cells) or enhance (Th2/M2 cells) tumor development. It was previously showed that Onconstatin M (OSM) had pleiotropic effects on cancer cells. OSM can promote cancer by inducing tumor cells motility, invasiveness or by reprogramming immune cells toward a more permissive phenotype (M2 polarization). Our previous data showed that OSM has proinflammatory effects on skin and modulate normal keratinocyte phenotype both in vitro and in vivo. In this study, we hypothesized that OSM could be involved in cSCC development. We showed that OSM was overexpressed in human cSCC as well as other cytokines such as IL-6, IL-1β, IFNγ whereas IL-4 was decreased, suggesting a Th1/M1 polarization of cSCC microenvironment. In vitro, OSM induced STAT-3 and ERK signalization, modified gene expression, promoted proliferation and migration of malignant keratinocyte PDVC57 cells. PDVC57 cells grafted in skin mice led to cSCC development associated to OSM overexpression by immune infiltrated cells. Finally, we showed that the absence of OSM led to a 30% reduction of tumor size and reduced M2 polarization in tumor microenvironment. Collectively, these results support a pro-tumoral role of OSM in cSCC development and suggest a new therapeutic approach targeting this cytokine.

INTRODUÇÃO: A incidência de câncer da glândula tireoide é a que mais vem crescendo nas últimas décadas. Dentro desse grupo de diferentes neoplasias, o carcinoma papilífero, um dos carcinomas bem diferenciados, representa a maioria e tem prognóstico favorável, com sobrevida acima dos 90% em 5 anos. Embora sejam utilizadas diversas classificações de risco baseadas em diferentes fatores prognósticos, ainda não se consegue predizer quais pacientes terão maior chance de recorrência, metástases linfonodais e desfecho desfavorável, que se beneficiariam de um tratamento mais agressivo. Já foi demonstrado em diversos tipos de neoplasias que diferenças no perfil do infiltrado imune tumoral têm relação com prognóstico e resposta ao tratamento. Neste estudo caracterizou-se o microambiente imune do carcinoma papilífero através de marcadores imuno-histoquímicos de células inflamatórias e relacionou-se este perfil de infiltração com fatores prognósticos clínico-patológicos e com sobrevida livre de recorrência. MÉTODOS: Foram incluídos 151 casos selecionados com base em um banco de dados que incluiu todos os pacientes submetidos a tratamento cirúrgico para câncer de tireoide no A.C.Camargo Cancer Center entre 2008 e 2010. Casos com tireoidite significante foram excluídos. Estes tumores selecionados foram então submetidos a reação imuno-histoquímica com marcadores de células inflamatórias e foram analisados por dois patologistas experientes. As características clínicas e patológicas foram avaliadas, assim como as recorrências e sobrevida, relacionando-as com as leituras de células marcadas. As análises de sobrevida global e livre de doença foram realizadas pelo método de Kaplan-Meier, com comparação de curvas de sobrevida pelo teste de Logrank. RESULTADOS: Cento e cinquenta e um pacientes foram incluídos, sendo 130 (86,1%) mulheres e 21 (13.9%) homens. Multifocalidade foi encontrada em 41 (27.2%), extensão extratireoidiana em 43 (28.5%) e metástase linfonodal em 36 (23.8%) casos. Apenas dois pacientes apresentaram metástase a distância. O tempo de seguimento médio foi 65,1 meses e observou-se nove (6%) pacientes com recorrências de neoplasia. Os pacientes com tumores com metástase linfonodal e/ou extensão extratireoidiana apresentaram maior risco de recorrência. Dos marcadores analisados, uma maior densidade de CD8 (que marca linfócitos citotóxicos) na área peritumoral esteve associada a uma tendência a melhor sobrevida livre de recorrência: 97,1% versus 87,5% (p=0,057), além de significativos menores índices de multifocalidade tumoral e de metástase linfonodal. A maior infiltração de linfócitos T CD8+ no tumor também se relacionou com menor ocorrência de metástase linfonodal nesta amostra (18,4% versus 38,1%, p=0,011). Além disso, a densidade desta marcação, tanto no interior da lesão neoplásica como em área peritumoral foi significativamente maior nos casos de carcinomas papilíferos restritos à tireoide, ou seja, sem extensão extratireoidiana e sem metástases. Os demais marcadores analisados não apresentaram relação significativa e consistente com recorrência ou outros fatores prognósticos. CONCLUSÕES: Nas neoplasias malignas de tireoide, o microambiente imune parece ter uma relação com características patológicas de agressividade. Este estudo mostrou que em carcinoma papilífero de tireoide quando não associado à tireoidite significativa, a densidade do infiltrado tumoral e peritumoral por linfócitos T CD8+ está inversamente relacionada com chance de disseminação metastática linfonodal e, provavelmente, com recidiva da doença, sendo, portanto, um marcador de melhor prognóstico. Este dado sugere que estes linfócitos exercem efeito antitumoral no carcinoma papilífero de tireoide, corroborando a importância da resposta imune na evolução desta neoplasia / INTRODUCTION: Within the last few decades thyroid cancer has the fastest rising incidence rate among all malignancies. In this group of different neoplasms, the papillary carcinoma, one of the well-differentiated carcinomas, represents the great majority and has favorable prognosis, with overall survival rates above 90% in five years. Although several risk classifications based on different prognostic features have been used, they are not accurate to predict which patients will have higher chance of recurrence, lymphatic metastasis and worse outcome, benefiting from more aggressive treatment. It has been described in several kinds of malignancies that tumor related immune infiltration has relation with prognosis and response to treatment. In this study, we characterize the immune microenvironment in papillary thyroid carcinomas, using immunohistochemical markers to inflammatory cells, and relate it with clinical and pathological prognostic features and with recurrence free survival rates. METHODS: The 151 included cases were selected from a database that included all patients who underwent surgical treatment for thyroid cancer at A.C.Camargo Cancer Center between the years 2008 and 2010. Tumor with significant thyroiditis were excluded. The selected tumors were submitted to immunohistochemical reactions with markers of inflammatory cells and analysis in complete slides by two experienced pathologists. Clinical and pathological features were evaluated, as well as recurrence and survival, relating them with the reading of marked cells. Survival analysis were made using Kaplan-Meier method, comparing survival curves with the Logrank test. RESULTS: One hundred and fifty one patients were included, of which 130 (86.1%) were females and 21 (13.9%) males. Multifocal disease was found in 41 cases (27.2%), extrathyroidal extension in 43 (28.5%) and lymph node metastasis in 36 (23.8%). Only two patients had distant metastasis. The mean follow-up time was 65.1 months and we observed nine (6%) tumor recurrences. Tumors with lymph node metastasis and/or extrathyroidal extension showed significantly higher recurrence rates. Of the analyzed markers, the cases with a higher density of CD8 (which marks cytotoxic T lymphocytes) in peritumoral areas presented a trend to better recurrence-free survival: 97.1% versus 87.5% (p=0.057), in addition to lower rates of mutifocal tumors and lymph node metastasis. A higher infiltration rate of CD8+ T lymphocytes in the tumor also correlated with less risk of lymph node metastasis in this sample (18.4% versus 38.1%, p=0.011). Besides that, the density of this marking both in the tumor and in peritumoral areas, was significantly higher in the papillary carcinomas limited to the thyroid gland (without extrathyroidal extension or metastasis). The other markers analyzed did not presented significant or consistent relation with recurrence or other prognostic factors. CONCLUSIONS: In thyroid cancer, the immune microenvironment seems to relate with pathological features of aggressiveness. This study showed that in papillary thyroid carcinomas without significant thyroiditis, the density of tumoral and peritumoral infiltration by CD8+ T lymphocytes is inversely related with lymph node metastasis rate and probably with recurrence, being therefore a marker of better prognosis. These data suggest that these lymphocytes play an anti-tumoral role in papillary thyroid carcinoma, supporting the implication of immune response in the progression of this neoplasm

INTRODUÇÃO: O carcinoma ductal in situ da mama é o estágio final antes do carcinoma ductal invasivo (CDI) no processo de carcinogênese mamária. As semelhanças histológicas, moleculares e imunoistoquímicas do epitélio nestas duas lesões tornaram improvável que o epitélio fosse o único responsável pelo processo de invasão estromal. Ao mesmo tempo, foram identificadas importantes alterações nas características do microambiente mamário durante esta transição. As células mioepiteliais, componente do microambiente e cuja rotura determina o diagnóstico histológico do carcinoma invasivo, tem papel direto ou indireto neste processo. A fim de predizer esse risco de invasão, propomos que as características das células mioepiteliais sejam investigadas em conjunto com as características intrínsecas do epitélio neoplásico. OBJETIVOS: Determinar os fatores morfológicos e moleculares das células epiteliais e os marcadores das células mioepiteliais do microambiente em carcinomas ductais in situ da mama relacionados ao risco de invasão estromal. MÉTODOS: Foram selecionados retrospectivamente 236 casos consecutivos com diagnóstico inicial de CDIS seguidos de ressecção cirúrgica na Divisão de Anatomia Patológica da Faculdade de Medicina da Universidade de São Paulo no período de janeiro de 2000 a dezembro de 2009, divididos nos grupos 1 (CDIS puro, 90 casos) e 2 (CDIS associado a carcinoma invasor, 146 casos). Blocos de microarranjos de tecido foram construídos com áreas representativas dos CDIS e CDI que foram, então, classificados nos perfis moleculares de acordo com o seu perfil imunoistoquímico. Os marcadores mioepiteliais (vimentina, AML, calponina, p63, CK5/6, SMMHC, CD10) foram avaliados de acordo com a expressão imunoistoquímica baixa ou alta. RESULTADOS: Os perfis moleculares dos componentes in situ e invasivo da mesma lesão foram semelhantes. Os CDIS de baixo grau histológico, em comparação aos CDIS de alto grau, apresentaram maior número de casos com perfil molecular luminal (143 vs. 18) e menor proporção de casos luminal/HER2-positivo (6 vs. 11), HER2 (4 vs. 27) e triplo-negativo (3 vs. 22). Os CDIS no grupo 1, em relação aos CDIS no grupo 2, tiveram maior proporção de casos com expressão de receptores hormonais (84.4% vs. 71,2%) menor expressão de HER2 (76,7% vs. 81,5%), mais perfis moleculares luminal/HER2-positivo (12,2% vs. 4,1%) e menos perfis triplo-negativos (4,4% vs. 14,4%). A expressão de CK5/6 nas células epiteliais do CDIS teve maior proporção entre o subtipo HER2 (34,5%), seguido pelo triplo-negativo (25%), luminal/HER2- negativo (15,4%) e luminal/HER2-positivo (12,5%). A expressão de CK5/6 foi maior nas células epiteliais dos CDIS do grupo 1 em relação aos CDIS do grupo 2 (30,6% vs. 11,3%). A expressão alta de SMMHC nas células mioepiteliais associou-se mais frequentemente aos CDIS do grupo 1 (88,2%) em relação aos CDIS do grupo 2 (11,8%), e esta diferença manteve-se tanto nos CDIS de baixo grau (85,7%) quanto nos de alto grau histológico (92,3%). A expressão baixa de CD10 nas células mioepiteliais associou-se mais frequentemente aos CDIS do grupo 2 (95,6%) em relação aos CDIS do grupo 1 (4,4%), e esta diferença manteve-se tanto nos CDIS de baixo grau (96,4%) quanto nos de alto grau histológico (94,1%). Não houve diferença na expressão de marcadores mioepiteliais de acordo com o perfil molecular baseado na imunoistoquímica. CONCLUSÕES: O risco de invasão estromal em CDIS está associado ao perfil molecular triplo-negativo e à perda de expressão do marcador CD10 pelas células mioepiteliais e é inversamente proporcional à expressão de CK5/6 pelas células neoplásicas e à forte expressão do marcador SMMHC nas células mioepiteliais / INTRODUCTION: Ductal carcinoma in situ is the last step preceding invasive ductal carcinoma in breast carcinogenesis. Histologic, molecular and immunohistochemistry similarities in epithelium of these components make improbable that epithelial changes are sole responsible for the stromal invasion. At the same time important changes were identified in mammary microenvironment during this transition. Myoepithelial cells, components of microenvironment and which rupture is the histological definition of stromal invasion, have a direct or indirect role in this process. We propose an associated investigation of myoepithelial cells and intrinsic neoplastic epithelium caracteristics in view of predict the risk of stromal invasion. OBJECTIVES: To determinate morphologic and molecular factors of epithelial cells and microenvironment myoepithelial cell markers related to stromal invasion risk in ductal carcinomas in situ of the breast. METHODS: 236 cases with initial diagnosis of DCIS followed by surgical ressection were retrospectively selected from Division of Surgical Pathology, Faculty of Medicine, Sao Paulo University from january 2000 to december 2009, divided in groups 1 (pure DCIS, 90 cases) and 2 (DCIS associated with invasive carcinoma, 146 cases). Tissue microarrays were constructed with selected areas of DCIS and IDC and those were then classificated in molecular subgroups according to its immunohistochemistry profile. Myoepithelial markers (vimentin, smooth muscle actin, calponin, p63, CK5/6, SMMHC, CD10) were avaliated according to its high or low immunohistochemistry expression. RESULTS: Molecular profiles of in situ and invasive components of the same tumor were similar. Low-grade DCIS showed more luminal profiles than highgrade DCIS (143 vs. 18), and less luminal/HER2-positive (6 vs. 11), HER2 (4 vs. 27) and triple-negative (3 vs. 22) profiles. Group 1 DCIS, compared to group 2 DCIS, showed more cases with hormonal receptor expression (84.4% vs. 71.2%), less expression of HER2 (76.7% vs. 81.5%), more luminal/HER2-positive (12.2% vs. 4.1%) and less triple-negative profiles (4.4% vs. 14.4%). CK5/6 expression in epithelial cells was more frequent in HER2 (34.5%) subtype followed by triple-negative (25%), luminal/HER2-negative (15.4%) and luminal/HER2-positive (12.5%). Epithelial cells in group 1 DCIS showed more CK5/6 expression than cells in group 2 DCIS (30.6% vs. 11.3%). High expression of SMMHC in myoepithelial cells was more frequent in group 1 DCIS (88.2%) than group 2 DCIS (11.8%) and this pattern was also mantained in low-grade DCIS (85.7%) and high-grade DCIS (92.3%). Low expression of CD10 in myoepithelial cells was more frequent in group 2 DCIS (95.6%) than group 1 DCIS (4.4%) and this pattern was also mantained in low-grade (96.4%) and high-grade DCIS (94.1%). There was no significant difference in expression of myoepithelial cells according to molecular profile classified by immunohistochemistry. CONCLUSIONS: Stromal invasion risk in DCIS is associated with triple-negative profile, CD10 expression loss in myoepithelial cells and inversely correlated with CK5/6 expression in neoplastic cells and high expression of SMMHC in myoepithelial cells

Le microenvironnement tumoral, l'angiogenèse tumorale et l'hypoxie jouent un rôle crucial dans la progression tumorale et le développement de thérapies de nombreux cancers. Les limites de pénétration des médicaments, les phénomènes de résistance aux anti-cancéreux, la vascularisation de la tumeur et l’hypoxie sont tous des paramètres influençant les effets du médicament. La culture cellulaire 3D permet de créer un microenvironnement qui imite l’architecture et la fonction des tissus in vivo. L’expression de gènes et de protéines modifiée par l’environnement 3D est une autre caractéristique qui impacte l’effet d’une molécule thérapeutique. Dans notre première étude, afin de développer un modèle 3D vascularisé imitant celle des tumeurs in vivo, nous avons mis en culture des cellules endothéliales en 2D avec des cellules tumorales en 3D. Après 2 semaines de culture, un réseau vasculaire s’est organisé avec des structures de type tubulaire présentant une lumière et exprimant différents marqueurs angiogéniques tels que VEGF, CD31 et Collagène IV. Dans notre deuxième étude, nous avons développé un modèle d’hypoxie in vitro intégrant l'environnement 3D et un agent mimétique de l'hypoxie (CoCl2). Le but de ce modèle est de créer un modèle d'hypoxie imitant les tumeurs in vivo et de montrer l'importance de l'hypoxie dans la réponse et la résistance aux médicaments. Ces résultats ont révélé que la meilleure condition était la combinaison 3D+CoCl2, conduisant à la surexpression des gènes relatifs à l’hypoxie (GLUT1/3, VEGF) et à la résistance aux médicaments (ABCG2, MRP1). L'angiogenèse et l'hypoxie sont des facteurs clés pour le microenvironnement tumoral in vivo et ils doivent être adoptés dans la conception de modèles tumoraux in vitro pour mieux sélectionner et cribler les médicaments anticancéreux. / The tumor microenvironment, tumor angiogenesis, and hypoxia play a critical role in the tumor progression and therapy development of many cancers. Limitations in drug penetration, multidrug resistance phenomena, tumor vascularization, and oxygen deficiency are all parameters influencing drug effects. 3D cell culture allows to create a microenvironment that more closely mimics in vivo tissue architecture and function, thus, gene and protein expression modified by the 3D environment are further features that affect treatment outcome. In our first study, in order to develop a vascularized 3D model like in vivo tumors, we co-cultured 2D endothelial cells with 3D tumor cells. After 2 weeks of this combination, a vascular network was formed and organized with tubule-like structures presenting a lumen and expressing different angiogenic markers such as VEGF, CD31 and Collagen IV. In our second study, we developed an in vitro hypoxia model integrating the 3D environment and a hypoxia mimetic agent (CoCl2) to mimic the in vivo tumors and to show the importance of hypoxia in drug response and resistance. Results revealed that the best condition was the combination 3D+CoCl2 model, leading to overexpression oh hypoxia (GLUT1/3, VEGF) and drug resistance (ABCG2, MRP1) related genes. Taken together, angiogenesis and hypoxia are key factors for in vivo tumor microenvironment and they should be adopted in in vitro model design to better select and screen anticancer drugs.

La Ténascine-C (TNC) est un composé majeur de la matrice extracellulaire tumorale et sa forte expression est directement corrélée à l’angiogenèse tumorale et au processus métastatique. Lors de ma thèse j’ai pu démontrer que la TNC dérégulait DKK1, un inhibiteur de la voie de signalisation Wnt et par ce biais augmentait l’activité de cette voie impliquée dans la cancérogenèse. La diminution de la formation des fibres de stress en présence de TNC est l’un des mécanismes majeurs qui contribue à la diminution de DKK1. L’activité de MKL1, facteur co-transcriptionnel de SRF et régulable par l’actine, s’avère diminuée en présence de TNC. Mes données indiquent que la fonction de MKL1 n’est peut-être pas le mécanisme majeur de la régulation de DKK1 par la statu de l’actine. D’autres facteurs, probablement liés aux fibres de stress d’actine pourraient être impliqués. L’augmentation de l’activité de la voie de signalisation Wnt, dépendante de DKK1, est probablement le mécanisme majeur par lequel la TNC active la progression tumorale. Cette étude a permis de mettre en évidence un nouveau mécanisme de régulation de DKK1 faisant intervenir l’intégrité du cytosquelette d’actine. / Tenascin-C (TNC) is a major component of the tumor specific extracellular matrix and its expression has been linked to tumor angiogenesis and metastasis. I demonstrated that TNC downregulates the expression of the Wnt signalling inhibitor DKK1 and by that enhances Wnt/-catenin signalling. Reduced stress fibre formation in the presence of TNC was identified as a major mechanism contributing to DKK1 downregulation. The activity of the actin-regulated SRF co-transcription factor MKL1 was found to be reduced in the presence of TNC. My results indicate that TNC-regulated MKL1 function maybe one, but not the major mechanism of DKK1 regulation by the actin status and that other factors, presumably regulated by actin stress fibres, are involved. Enhanced Wnt signalling activity downstream of TNC-induced DKK1 downregulation might be a major mechanism by which TNC promotes tumor progression. Furthermore, this study discovered a novel mechanism of regulating the Wnt inhibitor DKK1 by the integrity of the actin cytoskeleton.