Introdução: Indivíduos sobreviventes à sepse apresentam maior mortalidade à longo prazo e maior risco de apresentar infecções oportunistas. Existem evidências clínicas e experimentais de desregulação imune no estado pós-sepse. Essas alterações apresentam semelhança com aquelas encontradas no microambiente tumoral, estando relacionadas à imunossupressão. O presente trabalho avaliou o papel de macrófagos associados ao tumor (TAM) em modelo de progressão tumoral em camundongos sobreviventes à sepse. Materiais e Métodos: Camundongos C57/BL6 foram submetidos a ligadura e punção cecal (CLP) e tratados com ertapenem (20 mg/kg, i.p., 6 horas após CLP e 12/12 h por 3 dias). Os animais sobreviventes de sepse eram inoculados com células de melanoma B16-F10 (30 mil, s.c., 15 dias após a CLP). Animais naïve foram usados como controle. Foram avaliadas a progressão tumoral, sobrevida e formação de metástases espontâneas à distância. No D+14, animais foram sacrificados para mensuração do acúmulo de TAM por citometria de fluxo (CD45+F4/80+CD206+) e de citocinas no soro e no tumor por ELISA (IFN-?, IL-10, TNF-?, TGF-?, CCL2, CXCL12). Macrófagos derivados de medula óssea de animais pós-CLP ou naïve foram coinoculados com células B16 para avaliação de progressão tumoral e sobrevida. TAM de animais naïve ou pós-CLP foram isolados através de gradiente de Percoll seguido de adesão seletiva e o RNA foi isolado para análise diferencial de expressão gênica por microarray. Para avaliação da participação da via CXCL12/CXCR4 foi realizada sua inibição com o AMD3100, antagonista de CXCR4 (5 mg/kg, i.p., D+10 e D+14). Foi avaliada a progressão tumoral, sobrevida, acúmulo de TAM e proliferação extramedular de TAM no D+14. Resultados: Animais sobreviventes de sepse apresentaram aumento de progressão tumoral (após 15, 30 e 60 dias da CLP), aumento da carga de metástases (após 15 dias da CLP) e redução de sobrevida. Foi detectado o aumento de TAM nos animais pós-CLP, associado a maior marcação de Ki67, em comparação com animais naïve no D+14. Verificamos aumento das concentrações séricas de TGF-?, CXCL12, CCL2 e TNF-?. Camundongos naïve que coinoculados com macrófagos derivados de medula óssea de animais pós-CLP apresentaram aumento de progressão tumoral e redução de sobrevida em comparação com o grupo controle. TAM de animais pós-CLP apresentaram menor expressão de genes relacionados ao MHC-II e genes relacionados à ativação leucocitária. A inibição de CXCL12/CXCR4 preveniu a progressão tumoral induzida por sepse, com menor acúmulo de TAM e menor presença de TAM Ki67+. Conclusões: O estado pós-sepse promove a progressão tumoral de melanoma B16 em camundongos, o qual foi associado a aumento de 12 TAM. A via CXCL12/CXCR4 participa do processo de acúmulo de TAM nesse modelo experimental. / Background: Survivors from sepsis present higher long-term mortality and increased risk of opportunistic infections. There is clinical and experimental evidence for an immunosuppressive immune dysregulation in post-sepsis. These alterations are similar to those found in tumor microenvironment. The present work assessed the role of tumorassociated macrophage (TAM) in a model of tumor progression in sepsis-surviving mice. Materials and Methods: C57/BL6 mice were submitted to cecal ligation and puncture (CLP) and treated with ertapenem (20 mg/kg, ip. - 6 h after CLP and then each 12 h for 3 days). Sepsis surviving mice were inoculated with B16-F10 melanoma cells (30,000, sc., 15 days after CLP). Naïve mice were used as controls. Tumor progression, survival and distant spontaneous metastasis were evaluated. Mice were killed at D+14 for TAM measurement through flow cytometry (CD45+F4/80+CD206+) and for cytokines (IFN-?, IL-10, TNF-?, TGF-?, CCL2, CXCL12) quantification by ELISA. Bone marrow-derived macrophage (BMDM) were isolated and co-inoculated together with B16 melanoma cells for tumor progression and survival evaluation. TAM from naïve or post-sepsis mice were isolated through Percoll gradient (70/30) followed by selective adhesion. The RNA was isolated for gene expression analysis using microarray assay. To evaluate the role of CXCL12/CXCR4, we used the specific antagonist AMD3100 (5 mg/kg, ip., at D+10 and D+14) and assessed tumor progression, survival and TAM accumulation at D+14. Results: Sepsis-surviving mice showed increased tumor progression (15, 30 or 60 days after CLP), higher metastatic burden (15 days after CLP), and less overall survival. TAM were increased in post-sepsis mice at D+14. We found increased serum levels of TGF-?, CXCL12, CCL2 e TNF-?. Naïve mice inoculated with BMDM from post-sepsis and B16 cells showed higher tumoral progression and less survival, when compared to the control group. TAM from post-sepsis showed decreased expression of MHC-II related genes and genes related to leukocyte activation. The inhibition of CXCL12/CXCR4 prevented the post-sepsis-induced tumor progression, with less TAM accumulation and reduced expression of Ki67 in TAM. Conclusions: The post-sepsis state promotes the progression of B16 melanoma in mice, which was associated with an increase in TAM accumulation. CXCL12/CXCR4 mediates TAM accumulation in this experimental model.

O melanoma é a forma mais letal entre os cânceres de pele. Essa neoplasia freqüentemente apresenta-se resistente a abordagens terapêuticas. A angiogênese associada ao tumor representa um crítico passo da tumorigênese, resultado da ação de diferentes citocinas e fatores de crescimento como VEGF produzidos no microambiente tumoral. As galectinas extracelulares participam de múltiplos processos biológicos incluindo angiogênese tumoral e metástases, sua interação com as células presentes no microambiente tumoral pode ocorrer via receptores toll-like sugerindo seu envolvimento nos processos pro-inflamatórios e na secreção de citocinas. Recentemente mostramos que a ausência de gal-3 no estroma e parênquima tumoral diminui a angiogênese por interferir na resposta de macrófagos via VEGF e/ou TGFbeta1. Entretanto, o envolvimento de galectinas extracelulares na angiogênese e na modulação do sistema imune no microambiente tumoral ainda não está esclarecido. Assim, este estudo visa buscar respostas ao envolvimento das galectinas no crescimento tumoral e angiogênese contribuindo ao combate do melanoma maligno. Nossos resultados mostram a participação das galectinas 1 e 3 no crescimento tumoral e seu envolvimento com macrófagos via receptores toll-like, além de coordenarem a modulação do perfil de polarização de macrófagos derivados da medula óssea de camundongos wild-type. Dessa forma, podemos inferir que essas galectinas agem como coordenadoras de mudança de perfil dos macrófagos, uma vez que inibidas extracelularmente promovem uma diminuição do crescimento tumoral em camundongos wild-type, inoculados com células de melanoma murino e uma manutenção do perfil de macrófagos M1 in vitro. Assim, concluimos que as galectinas 1 e 3 extracelulares são importantes para o crescimento tumoral de melanomas murinos pois promovem o crescimento tumoral e são coordenadoras da mudança do perfil de macrófagos / Melanoma is the most aggressive form of skin cancer. This tumor often presents itself resistant to therapeutic approaches. The tumor-associated angiogenesis is a critical step in tumorigenesis and the result of the action of several cytokines and growth factors such as VEGF produced in the tumor microenvironment. The extracellular galectins participate in multiple biological processes including tumor angiogenesis and metastasis, their interaction with cells present in the tumor microenvironment may occur via toll-like receptors suggesting their involvement in pro-inflammatory processes and the secretion of cytokines. We have recently shown that the absence of Gal-3 the stroma and tumor parenchyma decreases angiogenesis by interfering with the macrophage response by VEGF and / or TGFbeta1. However, the involvement of extracellular galectins on angiogenesis modulation of the immune system in the tumor microenvironment is not yet clear. This study aims is to find answers to the involvement of galectins on tumor growth and angiogenesis contributing to the study of the malignant melanoma. Our results demonstrate the involvement of galectin 1 and 3 on tumor growth and its involvement in macrophage by toll-like receptors pathway, and coordinating the modulation of the polarization profile in wild-type mice bone marrow derived macrophages. Therefore, we show these galectins act as coordinators of macrophages profile change, since inhibited extracellularly promote a reduction in tumor growth in wild-type mice inoculated with murine melanoma cells and macrophages M1 maintenance of profile in vitro. Thus, we conclude that galectins 1 and 3 extracellular are important for tumor growth of murine melanomas because they promote tumor growth and are coordinators of change macrophages profile

Une expression élevée de la protéine de la matrice extracellulaire ténascine-C (TNC) favorise la progression du cancer et est corrélée à une réduction de la survie des patients. Dans cette thèse, j’ai étudié comment la TNC affecte l'angiogenèse tumorale. J’ai montré que la TNC altère les protrusions angiogéniques, la tubulogenèse, la migration et la prolifération des cellules endothéliales. J’ai lié ces effets à la perturbation du cytosquelette d'actine et la réduction de la signalisation YAP par la TNC. Chez les cellules tumorales et les fibroblastes associés au cancer, la TNC favorise la sécrétion de facteurs angio-modulateurs qui stimulent la survie et la tubulogenèse des cellules endothéliales de façon paracrine. Cet effet implique la régulation de l’expression de SDF1 (CXCL12) et de deux membres de la famille des lipocalines. Ainsi, la TNC favorise l’angiogenèse en activant chez les cellules tumorales un sécrétome pro-angiogénique, et inhibe la tubulogenèse en altérant la survie des cellules endothéliales. Ces effets opposés pourraient expliquer pourquoi nous avons observé dans un modèle de tumeur spontanée chez la souris que la TNC favorise le switch angiogénique résultant en la formation d’une forte vascularisation tumorale, mais qui reste peu fonctionnelle associée à la formation de plus de métastases. Ce travail fournit pour la première fois la possibilité de contrer l’action de la TNC dans l'angiogenèse tumorale. / A high expression of the extracellular matrix molecule tenascin-C (TNC) enhances multiple steps in cancer progression and correlates with worsened survival prognosis. In this thesis I studied how TNC affects tumor angiogenesis. I showed that TNC impairs endothelial sprouting, tubulogenesis, migration and proliferation. I linked this effect to disruption of the actin cytoskeleton and reduced YAP signaling activity by TNC. In tumor cells and cancer associated fibroblasts, TNC regulated secretion of angio-modulatory factors that promoted endothelial cell survival and tubulogenesis in a paracrine manner involving regulation of SDF1 (CXCL12) and two lipocalin family members. Altogether, TNC promotes endothelial tubulogenesis through a pro-angiogenic secretome from tumor cells, and inhibits by direct contact tubulogenesis by impairing endothelial cell survival. These opposing effects could explain why we observed that TNC promotes the tumor angiogenic switch resulting in more but poorly functional blood vessels associated with more metastasis in a spontaneous tumor mouse model. This knowledge provides for the first time opportunities to counteract TNC activities in tumor angiogenesis.

Le micro-environnement tumoral joue un rôle dans la croissance, l'invasion tumorale et la résistance aux traitements. Il est essentiel de comprendre les mécanismes qui régulent la communication entre les cellules tumorales et ce micro-environnement pour développer des thérapies efficaces. Dans ce contexte, les protéases extracellulaires de la famille des Adamalysines sont des acteurs importants dans la progression tumorale en agissant sur le remodelage de la matrice extracellulaire (MEC) et la biodisponibilité des médiateurs de communication cellulaire tels que les cytokines, les chimiokines et les facteurs de croissance. Mes travaux ont mis en évidence une nouvelle interaction entre ADAM12, un marqueur mésenchymateux induit au cours de la transition épithélio-mésenchymateuse (EMT) dépendante du TGF-β et ZO-1, une protéine d’échafaudage exprimée dans des jonctions serrées de cellules épithéliales. Ces deux protéines sont redistribuées, dans des structures de type invadopodes pour promouvoir la dégradation de la MEC. Nous avons par ailleurs réalisé un criblage in silico qui nous a permis d’identifier un cluster d’adamalysines dont les gènes sont co-exprimés chez des patients atteints d’un carcinome hépatocellulaire. Parmi ces adamalysines, nous avons mis en évidence la protéine ADAMTS12, qui joue un rôle clé dans le développement de la fibrose hépatique en lien avec une réponse inflammatoire aigüe ou chronique. / Tumor microenvironment plays a major role in tumor growth, invasion and resistance to treatments. Understanding the mechanisms that regulate communication between tumor cells and their microenvironment is essential to develop effective therapies. In this context, Adamalysin extracellular proteases play major role in tumor progression, by modulating the extracellular matrix (ECM) remodeling and the bioavailability of cell communication mediators such as cytokines, chemokines and growth factors. My work revealed a new interaction between ADAM12, a mesenchymal marker induced during the epithelial-mesenchymal transition (EMT) dependent on TGF-β and ZO-1, a scaffolding protein expressed in tight junctions of epithelial cells. Both proteins are redistributed in invadopodia-like structures to promote ECM degradation. In a second study, we carried out an in silico screening that allowed us to identify a cluster of Adamalysin genes co-expressed in patients with hepatocellular carcinoma. Among these Adamalysins we have studied the protein ADAMTS12 in more details, and shown that this protein plays a key role in the development of liver fibrosis involving an acute or chronic inflammatory response.

Indiana University-Purdue University Indianapolis (IUPUI) / Background: Cancer is the leading cause of death worldwide and as a result is one of the most studied topics in public health. Breast cancer and prostate cancer are the most common cancers among women and men respectively. Gene expression and image features are independently prognostic of patient survival. However, it is sometimes difficult to discern how the molecular profile, e.g., gene expression, of given cells relate to their spatial layout, i.e., topology, in the tumor microenvironment (TME). However, with the advent of spatial transcriptomics (ST) and integrative bioinformatics analysis techniques, we are now able to better understand the TME of common cancers. Method: In this paper, we aim to determine the genes that are correlated with image topology features (ITFs) in common cancers which we denote topology associated genes (TAGs). To achieve this objective, we generate the correlation coefficient between genes and image features after identifying the optimal number of clusters for each of them. Applying this correlation matrix to heatmap using R package pheatmap to visualize the correlation between the two sets. The objective of this study is to identify common themes for the genes correlated with ITFs and we can pursue this using functional enrichment analysis. Moreover, we also find the similarity between gene clusters and some image features clusters using the ranking of correlation coefficient in order to identify, compare and contrast the TAGs across breast and prostate cancer ST slides. Result: The analysis shows that there are groups of gene ontology terms that are common within breast cancer, prostate cancer, and across both cancers. Notably, extracellular matrix (ECM) related terms appeared regularly in all ST slides. Conclusion: We identified TAGs in every ST slide regardless of cancer type. These TAGs were enriched for ontology terms that add context to the ITFs generated from ST cancer slides.

Cancer development and progression vary depending on tumor type, localization, invasion, immunogenicity and the ability of immune system to become activated. There are frequent interactions between tumor cells and immune cells, occuring locally at the site of primary tumor or distally through paracrine signalling of various mediators and cytokines. The main subject of this PhD thesis is to study key factors and aspects of immune response in cancer patients. In the first part, we analyzed immune cells infiltrating tumor tissues of ovarian cancer patients at different stages of disease. We focused on the dynamics of immune response, primarily on frequency of individual T lymphocyte populations in peripheral blood and tumor infiltrating T lymphocytes in tumors of early and advanced stages of ovarian cancer. We found that during disease progression there is a gradual decrease of proinflammatory Th17 and Th1 immune responses and a specific recruitment of regulatory T cells to the tumor site, which results in a significant immune suppression in the tumor microenvironment. In the second part, we demonstrated that the character of immune response in HPV-positive head and neck cancer patients is very different from the patients with tumors not associated with HPV infection. In HPV-positive patients, significantly...

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The dissertation is focused on the study of intercellular interactions in skin tumors. It is based on 5 original publications that cover several topics. We studied the origin of tumor-associated fibroblasts concerning the primary tumor population. We demonstrated using a mouse model that tumor-associated fibroblasts are produced from the host organism and thus did not arise from transformation directly from tumor cells. We also investigated the relationship between tumor-associated fibroblasts and keratinocytes. We have shown that tumor-associated melanoma fibroblasts affect keratinocytes which, under their influence, acquire the features typically observed in migrating cells and cells undergoing epithelial-mesenchymal transition. We studied the interactions between healthy fibroblasts and tumor cells. We have demonstrated that fibroblasts acquired from healthy skin from a patient suffering from melanoma are significantly different from control fibroblasts of healthy donors in the expression profile. Changes in distal fibroblasts support the view of melanoma as a systemic disease. We have further demonstrated that melanoma-associated fibroblasts do not carry a BRAF mutation, in contrast to BRAF positivity of melanoma cells. And therefore, they did not arise from the transition from melanoma. The...

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