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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Fonctionnalisation de substrats pour l'étude des phénotypes de migration cellulaire

Roy, Joannie 12 1900 (has links)
No description available.
162

Perfil transcricional de fibroblastos de tumor primário, linfonodo e medula óssea de pacientes com câncer de mama / Transcriptional profile of fibroblasts obtained from primary tumor, lymph node and bone marrow of breast cancer patients

Del Valle, Paulo Roberto 01 March 2013 (has links)
Introdução: Em câncer de mama, existem evidências de que o microambiente pode influenciar o desenvolvimento do tumor no sítio primário, bem como em metástases regionais e a distância. Neste contexto, fibroblastos são importantes células estromais que podem influenciar a proliferação e a migração de células do câncer e podem prover um nicho apropriado para o desenvolvimento tumoral. Objetivos:O principal objetivo deste trabalho é comparar células estromais obtidas do tumor primário (PT), metástase linfonodal (N+) e medula óssea (BM) de pacientes com câncer de mama, através do perfil de expressão gênica. Pacientes e Métodos: Foi analisada a expressão gênica de fibroblastos (cultura primária) de 11 pacientes com câncer de mama. O perfil de expressão foi determinado em PT (n=4), N+(n=3) e BM (n=4) através de uma plataforma de cDNA microarray customizada (contendo 4.800 sequencias imobilizadas, representando cerca de 4600 genes), e os genes diferencialmente expressos foram identificados pelo teste SAM multiclasse, seguido pelo teste SAM de duas classes (TMEV, FDR 0%). A análise funcional foi realizada pelo software DAVID v6.7. Validação técnica foi realizada em 6 amostras previamente analisadas no microarray e a validação biológica em fibroblastos obtidos de outros 16 pacientes utilizando-se de RT-qPCR. Resultados: O perfil de expressão gênica dos fibroblastos obtidos de diferentes sítios mostraram 267 genes diferencialmente expressos, os quais apropriadamente agruparam os fibroblastos de acordo com suas origens (PT vs. N+ vs. BM). Apesar das diferenças entre PT e N+ serem representadas por 20 genes, as diferenças entre PT vs. BM e N+ vs BM foram mais significantes (235 e 245 genes diferencialmente expressos respectivamente). Análise funcional dos genes diferencialmente expressos mostrou enriquecimento de funções relacionadas ao desenvolvimento e morfogênese.A seguir, a expressão de alguns genes selecionados foi analisada em uma série diferente de amostras (validação biológica). Desse modo observamos que NOTCH2 confirmou uma alta expressão em N+ (vs. PT), e ADCY2, HECTD1, HNMT, LOX, MACF1 e USP16 confirmaram alta expressão em BM (vs PT). Conclusão:Em pacientes com câncer de mama, células estromais obtidas de diferentes origens apresentam um perfil de expressão gênica diferencial, o qual pode influenciar o comportamento do tumor / may influence tumor development in the primary site of breast cancer, as well as in regional and distant metastatic sites. In this context, fibroblasts are important stromal cells which influence proliferation and migration of cancer cells and may also provide an appropriate niche to tumor development. Objectives: The main objective of this work is the comparison of stromal cells from the primary tumor (PT), lymph node metastasis (N+) and bone marrow (BM) obtained from breast cancer patients, through gene expression profile. Patients and Methods: The gene expression profile was analyzed in fibroblasts primary culture from 11 breast cancer patients. The expression profiles of PT cells (n=4), N+ cells (n=3) and BM cells (n=4) were determined through a customized cDNA microarray platform (containing 4800 immobilized sequences which represents 4600 genes approximately). The analysis were performed by SAM multiclass (TMEV; FDR 0%), followed by SAM two classes test (TMEV; FDR 0%). Functional analysis was performed using DAVID v6.7. Technical validation was performed in same 6 samples that were previously analyzed in microarray experiments and biological validation was performed in fibroblasts obtained from other group of 16patients by RT-qPCR Results: The expression profile of fibroblasts obtained from three sites revealed 267 differentially expressed genes, which appropriately clustered fibroblasts in three different branches, in accordance with their origin (PT vs. N+ vs. BM). Although the differences between PT and N+ were represented by 20 genes, differences between PT vs. BM and N+ vs. BM were more significant (235 and 245 differentially expressed genes respectively). Functional analysis revealed enrichment of functions related to development and morphogenesis. Afterwards, the expression of some selected genes were analyzed in a different batch of samples (biological validation).Thereby, NOTCH2 confirmed high expression in N+ (vs. PT), and ADCY2, HECTD1, HNMT, LOX, MACF1 and USP16 confirmed high expression in BM (vs. PT). Conclusion: In breast cancer patients, stromal cells obtained from different origins present a differential gene expression profile, which may influence tumor behavior
163

Rôle du récepteur des androgènes dans les communications cellulaires au sein du cancer de la prostate / Role of androgen receptor in cellular communications in prostate cancer

Schreyer, Edwige 12 October 2018 (has links)
La castration représente le traitement de référence du cancer de la prostate à un stade avancé. Cependant, la plupart des patients rechute du fait notamment de l’émergence de variants tronqués constitutivement actifs du récepteur des androgènes (RA). Le microenvironnement tumoral, en particulier les fibroblastes associés au cancer (CAFs), favorisent largement la progression tumorale. Ils sont très hétérogènes et dérivent de plusieurs types cellulaires dont les cellules souches mésenchymateuses (MSCs). Afin de mettre à jour l’impact des variants du RA sur le microenvironnement tumoral, mon projet de thèse a porté sur l’étude des effets de ces variants du RA sur la différenciation des MSCs en CAFs. Les résultats obtenus m’ont permis de démontrer un impact positif du variant RA Q641X sur l’expression du facteur de différenciation VEGF par les cellules tumorales, ainsi que sur l’expression des marqueurs de différenciation en CAFs FSP-1, CXCL12, PDGFR-β, ainsi que VEGF, au niveau des MSCs. Ces données suggèrent que le variant RA Q641X est capable d’induire la différenciation des MSCs en CAFs, soulignant ainsi l’importance de développer de nouvelles stratégies thérapeutiques ciblant ces variants du RA. / Androgen ablation therapy remains the most common treatment for patients with advanced prostate cancer. However, most patients will relapse due to the emergence of truncated constitutively active androgen receptor (AR) variants. The tumor microenvironment is another necessary feature driving prostate cancer progression. Cancer associated fibroblasts (CAFs) are the major specialized stromal cells that favor tumor progression. These cells are very heterogeneous and derive from several other cell types as mesenchymal stem cells (MSCs). In order to highlight the impact of AR variants on surrounding tumor stroma, the aim of my project was to investigate the effects of these AR variants on MSCs differentiation into CAFs. I noticed that the expression of VEGF, a CAF differentiation factor, was upregulated in tumor cells expressing AR Q641X variant. Similarly, the expression of CAF differentiation markers FSP-1, CXCL12, PDGFR-β, and VEGF was enhanced in MSCs in presence of AR Q641X variant. These data highlight an unknown property of AR Q641X variant in prostate tumor cells that is its ability to induce MSCs differentiation into CAFs, underlining the urgent need to develop novel strategies targeting these AR variants.
164

Factors affecting aggressive oral tongue cancer invasion and development of in vitro models for chemoradiotherapy assay

Väyrynen, O. (Otto) 04 June 2019 (has links)
Abstract Tumor associated macrophages (TAMs) are linked to the invasion of oral tongue squamous cell carcinoma (OTSCC). We modified THP-1 leukemia cells to M1 (inflammatory), M2 (TAM-like) and R848 (imidazoquinoline-treated) type macrophages in order to examine their interactions with OTSCC-cells (HSC-3) by using different kinds of in vitro migration and invasion models. We observed that interaction of TAM-resembling M2-type macrophages with HSC-3 cells induced invasion and migration, whereas the influence of M1 macrophages reduced them. Patient response to chemoradiotherapy is highly reliant on the characteristics such as the aggressiveness and stage of the cancer. Therefore, new methods for treatment testing are needed in order to design personalized therapies. We tested the applicability and consistency of human TME mimicking tissue methods for analyzing the effects of chemoradiation using commercial OTSCC cell lines. Based on our trials, both our human uterine leiomyoma tissue -based matrix models provide viable platforms for future in vitro chemoradiotherapy testing. Conventionally pro-tumorigenic activities of matrix metalloproteinase (MMP)9 have been linked with oral squamous cell carcinoma, but recently its tumor-suppressor role has also been revealed. Our study provides strong evidence that MMP9 also has an anti-invasive effect in OTSCC and is a potential mediator of the protective effects of arresten in tongue cancer cells. / Tiivistelmä Makrofageilla on yhteys kielen levyepiteelikarsinooman invaasioon eli syöpäkasvaimen tunkeutumiseen ympäröivään kudokseen. Tutkimuksessamme muokkasimme ihmisen THP-1 leukemiasoluja kemiallisesti tulehdusreittejä aktivoiviksi M1-makrofageiksi, kasvaimeen liittyvien makrofagien kaltaisiksi M2-makrofageiksi sekä imidatsokinoliini-käsitellyiksi R848-makrofageiksi. Tarkoituksenamme oli tutkia makrofagien ja kielisyöpäsolujen vuorovaikutuksia erilaisilla in vitro migraatio- ja invaasiomalleilla. Anti-inflammatoristen, syövän etenemistä edesauttavien TAM-makrofagien kaltaisiksi erilaistetut M2-tyypin makrofagit lisäsivät HSC-3 kielikarsinoomasolujen invaasiota ja migraatiota, kun taas M1-tyypin makrofagien vaikutus oli päinvastainen. Potilaan vaste kemosädehoitoon riippuu syöpäkasvaimen ominaisuuksista, kuten syöpäsolujen aggressiivisuudesta ja syövän levinneisyysasteesta. Tämän vuoksi on tarve uusille menetelmille, joiden avulla voidaan ottaa huomioon potilaan sekä syöpätyypin yksilölliset ominaisuudet hoitoa suunniteltaessa. Testasimme syöpäkasvaimen mikroympäristöä mallintavien, ihmiskudokseen perustuvien menetelmien käyttökelpoisuutta ja luotettavuutta kemosädehoidon vaikutusten arvioimiseen. Testiemme perusteella myoomakudokseen pohjautuvat menetelmät voivat auttaa kemosädehoidon vaikutusten testauksessa. Matriksin metalloproteinaasi (MMP) 9:n on pitkään uskottu olevan yksinomaan syövän etenemistä edesauttava molekyyli. Viimeaikaisissa tutkimuksissa on myös havaittu, että MMP9:llä voi olla syövältä suojaavia vaikutuksia. Tutkimme MMP9:n vaikutusta kielisyöpäsoluihin ja havaitsimme, että MMP9:llä on myös invaasiota hillitseviä vaikutuksia. Lisäksi MMP9 saattaa toimia verisuonten muodostumista estävän arresten-molekyylin syövältä suojaavien mekanismien välittäjänä.
165

Rôle de la cytokine Leukemia Inhibitory Factor (LIF) dans l'activation et le maintien des fibroblastes pro-invasifs lors de la carcinogénèse / Role of Leukemia inhibitory Factor in the activation and maintenance of pro-invasive fibroblasts in cancer

Albrengues, Jean 03 December 2014 (has links)
Le stroma inflammatoire joue un rôle primordial lors de la carcinogénèse. Dans ce contexte, nous montrons que la cytokine LIF est à l'origine d'une population de fibroblastes capable de remodeler la matrice extracellulaire de manière à la rendre permissive à l'invasion collective des cellules tumorales. En effet, nous montrons que la production de LIF par les cellules tumorales et fibroblastiques, après une stimulation au TGFβ, va réguler les capacités contractiles et pro-invasives de ces dernières via la régulation du cytosquelette d'acto-myosine et de manière indépendante de l'expression de α-SMA. En effet, l'inhibition pharmacologique des kinases JAKs permet de bloquer l'environnement fibrotique des tumeurs et d'ainsi bloquer l'invasion des cellules tumorales in vitro et in vivo. Nous montrons ensuite que LIF est à l'origine d'un switch épigénétique responsable de l'activation constitutive de la voie de signalisation JAK1/STAT3. Ce processus, régulé par la forme acétylée de STAT3, et son interaction avec l'ADN methyltransférase DNMT3b permet l'hypermethylation du promoter de la phosphatase SHP1 et donc la phosphorylation constitutive de JAK1. Une fois mis en place, ce nouveau profil de méthylation est maintenu par DNMT1. La surexpression de LIF dans les carcinomes humains corréle avec un environnement fibrotique, la présence de nodules invasifs et un mauvais pronostic clinique. De même, il existe une forte corrélation négative entre l'acétylation de STAT3 et l'expression de SHP1 dans le stroma tumoral. Nos résultats montrent qu'inhiber l'activité des DNMT et des kinases JAK permet de reprogrammer les capacités pro-invasive des fibroblastes associés aux carcinomes. / Signaling crosstalk between tumor cells and fibroblasts confers proinvasive properties to the tumor microenvironment. We identify LIF as a tumor promoter that mediates proinvasive activation of stromal fibroblasts independent of alpha-smooth muscle actin expression. We demonstrate that a pulse of transforming growth factor β (TGF-β) establishes stable proinvasive fibroblast activation by inducing LIF production in both fibroblasts and tumor cells. In fibroblasts, LIF mediates TGF-β-dependent actomyosin contractility and extracellular matrix remodeling, which results in collective carcinoma cell invasion. Indeed, pharmacological inhibition of JAK activity by counteracts fibroblast-dependent carcinoma cell invasion in vitro and in vivo. We next unveil that LIF initiates an epigenetic switch leading to the constitutive activation of JAK1/STAT3 signaling, which results in sustained pro-invasive activity of fibroblasts. The process is mediated by p300-histone acetyltransferase acetylation of STAT3, and DNA methyltransferase DNMT3b, which induce the hypermethylation of SHP1 phosphatase promoter and results in constitutive phosphorylation of JAK1. Sustained JAK1/STAT3 signaling is maintained by DNMT1. Accordingly, carcinomas display strong LIF upregulation, which correlates with dense collagen fiber organization, cancer cell collective invasion, and poor clinical outcome. Moreover, we show that STAT3 acetylation and phosphorylation are inversely correlated with SHP1 expression in tumors stroma. Combined inhibition of DNMT activities and JAK signaling results in long-term reversion of CAF-associated pro-invasive activity and restoration of the wild-type fibroblast phenotype.
166

Empéripolèse des cellules de lymphomes humains Ramos par les fibroblastes

Oualha, Nadia 12 1900 (has links)
No description available.
167

Dipeptidyl peptidáza-IV a Fibroblastový aktivační protein v gliomagenezi. / Dipeptidyl peptidase-IV and Fibroblast activation protein in gliomagenesis.

Trylčová, Jana January 2018 (has links)
"Dipeptidyl peptidase-IV Activity and/or Structure Homologues"(DASH) represent a newly defined group of multifunctional molecules, typically bearing dipeptidyl peptidase-IV- like hydrolytic activity. Dipeptidyl peptidase-IV (DPP-IV) cleaves out X-Pro dipeptides from the N-terminus of peptides. Other molecules carrying similar enzyme activity, such as Fibroblast activation protein (FAP), DPP-II, DPP8 and DPP9 or even DPP-IV structure-like but hydrolytically inactive molecules (DPP6 and DPP10) also belong to this group. Recent knowledge suggest a substantial role of DASH in cancer pathogenesis. The aim of this study is a preparation of a biological model and its use for understanding the mechanisms of interaction(s) between transformed glial cells and stroma in the processes of origin and development of tumors derived from neuroectoderm. Stable transfected human glioblastoma cell lines with inducible gene expression of DPP-IV, Fibroblast activation protein and their enzymatically inactive mutated forms, were prepared within the project. Prepared cell lines are used as a tool for studying not only the "autocrine" importance of DPP-IV and FAP for the expressing cells in in-vitro, but also for their potential "paracrine" effect(s) within the tumor microenvironment after homotopic implantation into the...
168

Influência do microambiente no prognóstico do câncer da mama / Influence of the microenvironment on breast cancer prognosis

Fabiana Baroni Alves Makdissi 19 February 2014 (has links)
Introdução: Os cânceres de mama subtipos Luminal A e B (HER2 negativo) podem apresentar prognóstico variável, a depender do índice de proliferação, avaliado pelo Ki67. As células malignas e as células estromais adjacentes (fibroblastos e células de resposta imune ) podem interagir tanto pelo contato célula a célula como por fatores secretados por elas, ambas influenciando no comportamento tumoral. Já foi demonstrado que as células estromais podem aumentar a proliferação das células do câncer da mama. Objetivo: Nosso objetivo foi avaliar o perfil de expressão gênica de células do estroma em câncer de mama luminal A e luminal B e analisar se este se correlaciona com o prognóstico da doença. Pacientes e Métodos/ Resultados: Amostras de tumores de 11 pacientes na pós menopausa foram analisadas, todas elas HER2 negativas. A expressão de Ki67 foi <= 10 % em 5 pacientes (luminal A) e >= 30 % em outras 6 amostras(Luminal B ). Células estromais foram microdissecadas para a extração de RNA, que posteriormente foi hibridizado na plataforma de microarray Agilent G485 -1A GE 8x60K. Após a normalização, 50 % dos genes com a maior variância foram selecionados para análise por SAM duas classes desemparelhado (software TMEV ) e aceitando FDR 14.1%, 35 sequências foram identificadas como diferencialmente expressas, incluindo 16 genes conhecidos, entre as células estromais das amostras de Luminal A versos Luminal B, todos mais expressos nas amostras B. Dentre as funções biológicas enriquecidas em genes diferencialmente expressos encontram-se regulação positiva do sistema imune, incluindo genes como ZAP70 (proteína quinase 70kDa associada a cadeia zeta (TCR)), CD38 (molécula CD38); UBASH3A (ubiquitina associada e SH3 domínio que contém A); PLA2G7 (fosfolipase A2, grupo VII (fator acetil ativador de plaquetas no plasma)); NCR3 (citotoxicidade natural, provocando receptor 3). Nosso próximo passo foi avaliar se a expressão de alguns genes selecionados estava associada com prognóstico de tumores luminais. Para tal selecionamos amostras de outro grupo de 89 pacientes com seguimento de pelo menos 5 anos, cujos tumores eram ER(+), HER2(-), para análise de expressão proteica em Tissue microarray. Caracterizamos os fibroblastos destas amostras com 3 marcadores de fibroblastos: actina de músculo liso (AML), S100A4 e caveolina-1 (CAV1) e analisamos a marcação da proteína ZAP70. Correlacionamos a expressão proteica de todos os marcadores com as características anatomopatológicas da amostra. Observamos que fibroblastos de todas as amostras de tumor de mama expressam AML, S100A4 e CAV1, em diferentes proporções, entretanto não detectamos diferença entre os tumores luminais A e B. Também não obsevamos diferença de expressão de AML, S100A4 e CAV1 em relação a grau histológico, comprometimento linfonodal e estadiamento clínico. Nestas amostras não detectamos expressão proteica de ZAP70 em fibroblastos tumorais. Conclusão: Houve expressão diferencial de 16 genes relacionados a processos imunes, todos eles mais expressos em células estromais de tumores Luminal B em relação a luminal A / Introduction: Luminal breast cancer subtypes A and B (HER2 negative) may present a variable prognosis, depending on tumor proliferation index, evaluated by Ki67 expression. Malignant cells and adjacent stromal cells (fibroblasts and immune response cells) may interact by both cell contact and secreted factors and influence tumor behavior. It was shown that stromal cells may enhance breast cancer cells proliferation. Objective: Our aim was to evaluate stromal cells gene expression profile in luminal A and luminal B tumors and to evaluate whether selected transcripts expressed in stromal cells may be associated with prognosis in breast cancer. Material/ Methods and Results: Hormone receptor positive tumor samples from 11 post menopausal patients were analyzed, all of them Her2 negative. Ki67 expression <= 10% (luminal A) was observed in five and Ki67 >= 30% (luminal B) in six samples. Stromal cells were microdissected for RNA extraction, which was hybridized in Agilent G485-1A GE 8x60K microarray platform. After normalization, 50% of the genes with the highest variance were selected for further analysis by two class unpaired SAM (TMEV software) and accepting FDR 14,1%, 35 sequences, including 16 known genes, were found differentially expressed between stromal cells from luminal A vs luminal B breast cancer samples, all of them more expressed in luminal B. Among biological functions enriched in genes found differentially expressed were positive regulation of immune system process, including genes as: ZAP70 (zeta-chain (TCR) associated protein kinase 70kDa); CD38 (CD38 molecule); UBASH3A (ubiquitin associated and SH3 domain containing A); PLA2G7 (phospholipase A2, group VII (platelet-activating factor acetylhydrolase, plasma); NCR3 (natural cytotoxicity triggering receptor 3). Our next step was evaluate whether expression of selected genes was associated with prognosis in another group of patients. Tumor samples from 89 patients with at least 5 years of follow up, all of them estrogen receptor positive and HER2 negative, were selected. Tissue microarray was prepared with stromal tumor compartment from paraffin embedded tumor samples. Fibroblasts were characterized for the expression of 3 fibroblasts markers (alfa-SMA, alpha smooth muscel actin; S100A4 and CAV1, caveolin 1), and ZAP70. Correlation of expression of these markers with prognostic variables was determined. Expression of alfa-SMA, S100A4 and CAV1 was detected in fibroblasts from all tumor samples in different proportions, however no differential expression was observed between luminal A and B tumors. Neither difference was detected on the expression of these proteins in relation with histological grade, lymph node involvement and clinical stage. Conclusion: A differential expression of 16 genes involved in immune process was found, all of them more expressed in fibroblasts from luminal B as compared with luminal A tumors
169

Perfil transcricional de fibroblastos de tumor primário, linfonodo e medula óssea de pacientes com câncer de mama / Transcriptional profile of fibroblasts obtained from primary tumor, lymph node and bone marrow of breast cancer patients

Paulo Roberto Del Valle 01 March 2013 (has links)
Introdução: Em câncer de mama, existem evidências de que o microambiente pode influenciar o desenvolvimento do tumor no sítio primário, bem como em metástases regionais e a distância. Neste contexto, fibroblastos são importantes células estromais que podem influenciar a proliferação e a migração de células do câncer e podem prover um nicho apropriado para o desenvolvimento tumoral. Objetivos:O principal objetivo deste trabalho é comparar células estromais obtidas do tumor primário (PT), metástase linfonodal (N+) e medula óssea (BM) de pacientes com câncer de mama, através do perfil de expressão gênica. Pacientes e Métodos: Foi analisada a expressão gênica de fibroblastos (cultura primária) de 11 pacientes com câncer de mama. O perfil de expressão foi determinado em PT (n=4), N+(n=3) e BM (n=4) através de uma plataforma de cDNA microarray customizada (contendo 4.800 sequencias imobilizadas, representando cerca de 4600 genes), e os genes diferencialmente expressos foram identificados pelo teste SAM multiclasse, seguido pelo teste SAM de duas classes (TMEV, FDR 0%). A análise funcional foi realizada pelo software DAVID v6.7. Validação técnica foi realizada em 6 amostras previamente analisadas no microarray e a validação biológica em fibroblastos obtidos de outros 16 pacientes utilizando-se de RT-qPCR. Resultados: O perfil de expressão gênica dos fibroblastos obtidos de diferentes sítios mostraram 267 genes diferencialmente expressos, os quais apropriadamente agruparam os fibroblastos de acordo com suas origens (PT vs. N+ vs. BM). Apesar das diferenças entre PT e N+ serem representadas por 20 genes, as diferenças entre PT vs. BM e N+ vs BM foram mais significantes (235 e 245 genes diferencialmente expressos respectivamente). Análise funcional dos genes diferencialmente expressos mostrou enriquecimento de funções relacionadas ao desenvolvimento e morfogênese.A seguir, a expressão de alguns genes selecionados foi analisada em uma série diferente de amostras (validação biológica). Desse modo observamos que NOTCH2 confirmou uma alta expressão em N+ (vs. PT), e ADCY2, HECTD1, HNMT, LOX, MACF1 e USP16 confirmaram alta expressão em BM (vs PT). Conclusão:Em pacientes com câncer de mama, células estromais obtidas de diferentes origens apresentam um perfil de expressão gênica diferencial, o qual pode influenciar o comportamento do tumor / may influence tumor development in the primary site of breast cancer, as well as in regional and distant metastatic sites. In this context, fibroblasts are important stromal cells which influence proliferation and migration of cancer cells and may also provide an appropriate niche to tumor development. Objectives: The main objective of this work is the comparison of stromal cells from the primary tumor (PT), lymph node metastasis (N+) and bone marrow (BM) obtained from breast cancer patients, through gene expression profile. Patients and Methods: The gene expression profile was analyzed in fibroblasts primary culture from 11 breast cancer patients. The expression profiles of PT cells (n=4), N+ cells (n=3) and BM cells (n=4) were determined through a customized cDNA microarray platform (containing 4800 immobilized sequences which represents 4600 genes approximately). The analysis were performed by SAM multiclass (TMEV; FDR 0%), followed by SAM two classes test (TMEV; FDR 0%). Functional analysis was performed using DAVID v6.7. Technical validation was performed in same 6 samples that were previously analyzed in microarray experiments and biological validation was performed in fibroblasts obtained from other group of 16patients by RT-qPCR Results: The expression profile of fibroblasts obtained from three sites revealed 267 differentially expressed genes, which appropriately clustered fibroblasts in three different branches, in accordance with their origin (PT vs. N+ vs. BM). Although the differences between PT and N+ were represented by 20 genes, differences between PT vs. BM and N+ vs. BM were more significant (235 and 245 differentially expressed genes respectively). Functional analysis revealed enrichment of functions related to development and morphogenesis. Afterwards, the expression of some selected genes were analyzed in a different batch of samples (biological validation).Thereby, NOTCH2 confirmed high expression in N+ (vs. PT), and ADCY2, HECTD1, HNMT, LOX, MACF1 and USP16 confirmed high expression in BM (vs. PT). Conclusion: In breast cancer patients, stromal cells obtained from different origins present a differential gene expression profile, which may influence tumor behavior
170

The microenvironment is essential for OTSCC progression

Alahuhta, I. (Ilkka) 25 October 2016 (has links)
Abstract The tumor microenvironment (TME) is critically important for tumor development. The microenvironment consists of fibroblasts, endothelial and immune cells as well as extracellular matrix (ECM), proteases and various other soluble factors produced by the cells. It is challenging to develop methods that appropriately mimic the human microenvironment, but this effort is essential in order to reliably elucidate the properties of potential anti-tumor drugs. The aim of this study was to create new 3D organotypic invasion models based on human tissue that would be used to study the effects of the anti-angiogenic molecules arresten and endostatin on tongue squamous carcinoma cells. The classic way to study cancer invasion has been to use a collagen invasion model that is created by mixing rat type I collagen, matrix produced by mouse EHS tumor cells and human fibroblasts. Our research group has developed a novel human myoma tissue based invasion model, which is composed of several different cell types and molecules that are normally present in the human TME. We show how this model is suitable for invasion studies, not only for oral cancer, but for other invasive cell lines as well. There are several matrix-derived fragments that have been shown to possess anti-angiogenic activity. Arresten is a 26 kDa fragment that is cleaved from type IV collagen and is known to inhibit angiogenesis, the formation of new capillaries and tumor growth in vivo. However, its effect on the tumor microenvironment in addition to endothelial cells has not been studied. We show that arresten also directly affects oral cancer cells by decreasing their migration and invasion as well as tumor size, invasion and angiogenesis in in vivo mouse xenografts. Another inhibitor of angiogenesis, endostatin, is cleaved from type XVIII collagen. It has been shown to suppress angiogenesis and tumor growth without toxicity or side effects in mouse models. Our studies show that endostatin directly affects tongue squamous carcinoma cells by reducing their invasion and spreading in organotypic 3D assays and mouse tumor models. In summary, arresten and endostatin are anti-angiogenic as well as anti-invasive molecules and therefore potential cancer drugs. They seem to have a direct effect on carcinoma cells making the cells less invasive. The myoma model allows us to study the effects of anti-cancer molecules with a new prospective. / Tiivistelmä Syövän mikroympäristö on erittäin tärkeä syövän kehittymisen kannalta. Se koostuu fibroblasteista, endoteeli- ja immuunisoluista, soluväliaineesta, proteaaseista ja monista muista solujen tuottamista liukoisista molekyyleistä. On haastavaa kehittää uusia menetelmiä, jotka jäljittelisivät oikeaa ihmisen syövän mikroympäristöä, mutta se on välttämätöntä uusien syöpälääkkeiden tutkimiseksi. Väitöstutkimuksen tavoitteena oli kehittää kolmiulotteinen ihmisen myoomakudokseen perustuvan invaasiomalli, jonka avulla voisimme tutkia verisuonten kasvua estävien arresten ja endostatin molekyylien vaikutusta kielisyöpäsoluihin. Aiemin syövän invaasiota on tutkittu käyttämällä klassista kollageeni-invaasiomallia, joka tehdään sekoittamalla rotan tyypin I kollageeniä, hiiren sarkoomasolujen tuottamaa matriksia ja ihmisen fibroblasteja. Tutkimuksissamme kehitimme uuden invaasiomallin, joka perustuu ihmisen myoomakudokseen. Tutkimuksessa sen todettiin sisältävän monia erilaisia soluja ja molekyylejä, joita on normaalistikkin syövän mikroympäristössä. Lisäksi osoitimme, että se sopii invaasiotutkimuksiin monille syöpätyypeille. Soluvälitilamatriksista pilkotaan useita erilaisia molekyylejä joilla on osoitettu olevan angiogeneesia hillitseviä ominaisuuksia. Arresten on 26 kDa kokoinen polypeptidi, jota pilkotaan tyypin IV kollageenista. Sen tiedetään vähentävän angiogeneesia – uusien verisuonten muodostumista ja syövän kasvua in vivo. Sen vaikutuksia muihin kuin endoteelisoluihin ei ole kuitenkaan tutkittu. Tutkimuksissamme se vaikutti suoraan kielisyöpäsoluihin vähentäen niiden liikkumista ja invaasiota kolmiulotteisissa organotyyppisisssä malleissa ja hiirimallissa. Toinen tutkimamme angiogeneesin inhibiittori on endostatin, jota pilkotaan tyypin XVIII kollageenista. Sen tiedetään vähentävän angiogeneesia hiirimalleissa ilman toksisia sivuvaikutuksia. Me osoitimme tutkimuksissamme, että se vaikuttaa suoraan kielisyöpäsoluihin vähentäen niiden invaasiota ja leviämistä 3D organotyyppisissä malleissa sekä hiirikokeissa. Koska arresten ja endostatin ovat anti-angiogeenisiä ja anti-invasiivisia molekyylejä, ne ovat täten potentiaalisia syöpälääkkeitä. Ne näyttäisivät vaikuttavan suoraan syöpäsoluihin vähentämällä niiden invaasiota. Myoomainvaasiomalli mahdollistaa syöpää ehkäisevien molekyylien tutkimisen uudella ja todenmukaisemmalla tavalla.

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