Dissertations / Theses on the topic 'Cancer du sein – Immunothérapie'
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Kishi, Masae. "Strategies of Cancer Immunotherapy : Model of Triple Negative Breast Cancer." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS070.
Full textCancer stem cells (CSCs) are responsible for tumor progression, metastases, and late relapses. They have been identified in many cancers, such as triple negative breast cancer (TNBC) and grade III to IV cancers. They are resistant to chemotherapy and radiotherapy and reside in an immuno-repressive niche.This study aims to evaluate a immunotherapy strategy that selectively targets CSCs in the mouse model 4T1-GFP-Luc mimicking TNBC. The phenotype / genotype of mammosphere was initially characterized. Based on genomic analysis of CSC, we have developed an active immunotherapy associated with immunomodulatory agents. We measured the size of tumors and monitored the appearance of metastases by bioluminescence. We performed an immunological study and genomic tumor analysis. The therapeutic combination causes the recruitment of CD4 + and CD8 + T lymphocytes and B lymphocytes with increased CXCL13, the reduction of T reg cells and suppressive myeloid cells in the tumor. This induction of intra-tumor immune response leads to a decrease in tumor size and metastases.This new active immunotherapy can be used in combination with current treatments for prophylactic and curative measures in a wide variety of cancers
Kishi, Masae. "Strategies of Cancer Immunotherapy : Model of Triple Negative Breast Cancer." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS070.
Full textCancer stem cells (CSCs) are responsible for tumor progression, metastases, and late relapses. They have been identified in many cancers, such as triple negative breast cancer (TNBC) and grade III to IV cancers. They are resistant to chemotherapy and radiotherapy and reside in an immuno-repressive niche.This study aims to evaluate a immunotherapy strategy that selectively targets CSCs in the mouse model 4T1-GFP-Luc mimicking TNBC. The phenotype / genotype of mammosphere was initially characterized. Based on genomic analysis of CSC, we have developed an active immunotherapy associated with immunomodulatory agents. We measured the size of tumors and monitored the appearance of metastases by bioluminescence. We performed an immunological study and genomic tumor analysis. The therapeutic combination causes the recruitment of CD4 + and CD8 + T lymphocytes and B lymphocytes with increased CXCL13, the reduction of T reg cells and suppressive myeloid cells in the tumor. This induction of intra-tumor immune response leads to a decrease in tumor size and metastases.This new active immunotherapy can be used in combination with current treatments for prophylactic and curative measures in a wide variety of cancers
Kalfeist, Laura. "Optimisation immunologique et thérapeutique des doublets de chimio-immunothérapie dans le cancer du sein triple négatif." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCI010.
Full textThe clinical benefit of chemoimmunotherapy in metastatic triple-negative breast cancer (mTNBC) remains limited. Only patients with PD-L1-positive tumors, known as “hot” tumors, benefit significantly. Conversely, PD-L1-negative or “cold” tumors do not respond to this approach. In this context, it is crucial to identify therapeutic strategies capable of stimulating the immune response and inducing PD-L1 expression, in order to make these “cold” tumors sensitive to blockade of the PD-(L)1 pathway. Understanding resistance mechanisms and optimizing current chemoimmunotherapy combinations are therefore essential. To this end, this thesis explored three major projects and highlighted that: i) The low immunogenicity of taxanes, combined with corticoids, limits their immunological efficacy in combination with anti-PD-1 to treat “cold” tumors. ii) The second project characterized the immunological and therapeutic effects of the cisplatin/eribulin combination with anti-PD-L1, revealing an immunogenic potential amplified by chemotherapy-induced TGF-β blockade. iii) Finally, a screening of targeted therapies identified the HDAC inhibitor quisinostat as a promising candidate to induce CXCL10 expression, essential for CTL recruitment in tumors, when combined with carboplatin. This combination reactivates the cGAS pathway and the expression of type I IFNs, required for CXCL10 secretion. Overall, this work has made it possible to characterize the immunogenicity of certain chemotherapies used in mTNSCC (taxanes, platinum salts, eribulin), and to propose new, more rational chemoimmunotherapy combinations
Eymard, Jean-Christophe. "Innovation thérapeutique dans le cancer du sein et de la prostate : de la tentative d'optimisation d'une stratégie thérapeutique conventionnelle à l'exploration d'un nouveau concept d'immunothérapie cellulaire." Reims, 2008. http://theses.univ-reims.fr/exl-doc/GED00000868.pdf.
Full textLüscher, Débora. "Étude des lymphocytes T infiltrant le tissu tumoral." Master's thesis, Université Laval, 2006. http://hdl.handle.net/20.500.11794/19414.
Full textLe, Mercier Isabelle. "Caractérisation des altérations fonctionnelles des cellules dendritiques plasmacytoïdes et myéloïdes dans les tumeurs mammaires murines." Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00876658.
Full textDesfrancois-Noel, Juliette. "Les lymphocytes Tαβ CD4+CD8+ : de nouveaux acteurs de la réponse anti-tumorale dans le cancer du sein et le mélanome." Nantes, 2009. http://www.theses.fr/2009NANT2063.
Full textPons-Tostivint, Elvire. "Stratégies thérapeutiques innovantes pour stimuler la réponse immune antitumorale de cytotoxiques utilisés pour le traitement des cancers du sein." Thesis, Toulouse 3, 2021. http://www.theses.fr/2021TOU30216.
Full textLast decade, several pre-clinical and clinical studies well demonstrated that the efficacy of conventional chemotherapies involves an immunological component. A part of the explanation comes from the demonstration that conventional chemotherapies can boost the adjuvanticity of cancer cells by inducing an immunogenic cell death (ICD). ICD of tumour cells drive an inflammatory response characterized by the activation of dendritic cells and the initiation of a cytotoxic T-lymphocyte immunity. During ICD, the reticulum endoplasmic stress promotes the translocation of the calreticulin protein to the cell surface, that facilitates the phagocytic uptake of tumour cells by immature dendritic cells. Then, the activation of autophagy in tumor cells induces the lysosomal secretion of ATP, that promotes the recruitment of dendritic cells. Lastly, dying cancer cells release a large amount of nuclear proteins including HMGB1, that drives the maturation of dendritic cells upon binding to TLR4. TNBC is defined as the most aggressive subtype of breast cancer, classified by its lack of expression of the hormonal receptor and the human epidermal growth factor receptor 2, but also considered as the most immunogenic subtype of breast cancer. A subset of TNBC patients are now eligible for immunotherapy in combination with chemotherapy, but all of them will finally relapse, mostly during the first year of treatment. Development of novel therapeutics to optimize immune response in these patients is urgently needed. Dendrogenin A has been characterized by the Marc Poirot's team as a tumour suppressor metabolite present in normal breast tissue, but absent in neoplastic breast tumour. DDA has an anti-tumour activity demonstrated in hormone-dependent breast cancer and melanoma cells, through the induction of an LXRß-dependent autophagy. During my thesis, we showed that DDA elicit cell death and autophagy in triple-negative breast cancer (TNBC) models in vitro and in vivo. Then, we demonstrated that DDA induced hallmarks of ICD in vitro in TNBC and melanoma cells lines. Indeed, we demonstrated that a treatment with DDA trigger (1) surface exposure of CALR, (2) release of ATP in the supernatant in an autophagy-dependent manner, and (3) release of HMGB1 in the supernatant. These danger signals were induced by DDA in a larger extent than doxorubicin and mafosfamide, described as two ICD-inducers. We then demonstrated in two different models that cancer cells undergoing ICD after being treated with DDA provide partial immune-mediated prophylactic protection against a subsequent challenge with living cancer cells of the same type. These results suggested that DDA could be a new therapeutic developed to potentiate antitumoral immune response in TNBC
Burlion, Aude. "Ciblage de la molécule de costimulation ICOS pour l'immunothérapie du cancer du sein dans un modèle de souris humanisée." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066476.
Full textCheckpoint blockade inhibitors are the most promising and effective strategy for t-cell mediated cancer immunotherapy of the past 20 years. Part of the anti-tumoral effect of these checkpoint inhibitors might be due to regulatory T cell (treg) depletion. Here, we investigated whether the reported high expression of icos on treg might be used as a flag to target treg and improve tumor rejection. We report that a novel anti-human icos mab preferentially depleted treg in immunodeficient nsg mice reconstituted with cd34+ progenitors, leading to an increased cd8+/treg ratio. However, this was insufficent to affect growth of the breast cancer cell line mda-mb-231. We thus administered low dose cyclophosphamide (ctx) to induce immunogenic cell death and stimulate anti-tumor response. Treatment of humanized mice with a combination of ctx+ anti-icos mab led to a drastic reduction in tumor growth whereas single treatments had only moderated effect. Using mass cytometry (cytof), we observed higher expression of cd45ro, hla-dr and ki67 on tcd8+ of the combined-treatment group. Accordingly, depletion of cd8+ t cells partly abolished the therapeutic effect of the combination. Moreover, additional analyses suggest that human monocytes and pdc and murine myeloid cells are involved in this effect. Altogether, our results represent the first demonstration that humanized mice can be used to develop novel therapeutic strategies for cancer immunotherapy and indicate that targeting treg with a combination of anti-icos mab and chemotherapy is a relevant strategy to release the immune response to the tumor
Faget, Julien. "Les lymphocytes T CD4 régulateurs dans le cancer du sein, recrutement, enrichissement par les cellules dendritiques plasmacytoïdes et impact de l’axe de co-stimulation ICOS/ICOSL." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10310/document.
Full textTumor immunosbversion favors disease progression and is mediated by increased IL-10 secretion, reduced type-I IFN production and regulatory T cell (Treg) accumulation among CD4+ T cell in breast tumor. We showed that the presence of high number of both Treg and/or plasmacytoid DC (pDC) a subpopulation of antigen presenting celles correlates with poor prognosis in breast carcinoma. We previoously demonstrated that CCR4+ Treg are recruited from the periphery trough CCL22 production by breast tumor cells. Tumor-asssociated Treg (Ta-Treg) are highly activated (GITRhighHDLA-DRhighCD39high), show a selective expression of high levels of ICOS and proliferate in situ (Ki-67+). Tumor associated (Ta-) pDC express a partially activated phenotype but their type-1 interferon (IFN) production is strongly impaired in human tumors. pDc secretion of type-I IFN is linked to their capacity to induce anti-viral and anti-tumor immunity in mice models. We shown that 1) Ta-Treg and Ta-pDC colocalize in breast tumor section and 2) TapDC favor Ta-Treg proliferation and IL-10 secretion by CD4+ T cells in absence of type-I IFN. Ogf importance, targeting ICOS with a neutralizing antibody suppresses Ta-Treg proliferation as well as IL-10 secretion inpDC/CD4+ T cell co-culture, demonstrationg a riole of ICOS-ICOS-L interaction in Ta-Treg proliferation mediated by Ta-pDC. At the end, we report that high ICOS expression in breast tumor sections is associated with reduced patient's overall and disease free survival. Altogether these observations suggest that ICOS in breat cancer may represent a therapeutic target to restore anti-tumor immunity
Prat, Mélissa. "Les macrophages au sein du microenvironnement tumoral : étude et modulation des mécanismes moléculaires et cellulaires de la réponse anti-tumorale au cours de carcinoses péritonéales." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30116.
Full textMacrophages, which are crucial effectors of innate immune response, exhibit a remarkable phenotypic and functional plasticity that allows them to adapt to the different stimuli present in their microenvironment. Within the tumor microenvironment, macrophages or TAMs (Tumor-associated macrophages) represent the major leukocyte population. During tumor development, secreted mediators produced by transformed cells « educate » TAMs which acquire properties favorable to tumor growth. Thus, it is now widely accepted that TAMs, initially of anti-tumor M1 phenotype, differentiate towards an M2 phenotype able to promote tumor cell proliferation, angiogenesis, metastases, resistance to chemotherapy treatments and suppression of the adaptive anti-tumor immune response. However, this functional M1/M2 dichotomy, while facilitating the description TAMs phenotype and their associated functions, is an oversimplification of the macrophage biology within tumor tissues which is actually more complex. Thus, in the first part of this work, we showed that treatment with IL-13, a Th2 cytokine well described to be involved in macrophage M2 polarization, inhibits tumor growth in two murine models of T-cell lymphoma and ovarian adenocarcinoma via the promotion of macrophage cytotoxic activity. Interestingly, we demonstrated the key role of Mannose (RM) and Dectin-1 C-type Lectin receptors, strongly expressed on IL-13-activated macrophages, in tumor cell recognition. We specifically identified the sialic acid expressed on transformed cell surface as a critical epitope for their recognition by IL-13-activated macrophages. Moreover, we showed that, following this recognition, RM and Dectin-1 trigger cytotoxic signaling pathways leading to the production of radical oxygen species and the amplification of arginase activity. We finally demonstrated that these two mediators produced by IL-13-activated macrophages induce tumor cell necrosis. In the second part of this work, we studied the impact of 15(S)-HETE, a natural ligand of the PPAR-γ nuclear receptor involved macrophage M2 polarization, on tumor development. We showed that this lipid inhibits tumor growth in an experimental murine model of ovarian adenocarcinoma. Interestingly, we demonstrated that 15(S)-HETE anti-tumor effect depends on the activation of PPAR-γ in macrophages. We showed that 15(S)-HETE modifies peritoneal macrophage population balance, likely by promoting the differentiation of Small Peritoneal Macrophages (SPM) into Large Peritoneal Macrophages (LPMs). These LPMs display a phenotype which contributes to the increase of effector/regulatory T lymphocyte ratio in tumor ascites, and thus counteracts tumor-induced immunosuppression. Finally, in the third part of our work, the analysis of circulating blood monocytes in ovarian adenocarcinoma patients revealed a strong increase in the proportion of the « intermediate » subset (CD14high CD16+), usually poorly represented in healthy subjects. Interestingly, we demonstrated a positive correlation between a high proportion of intermediate blood monocytes and the presence of an immunosuppressive microenvironment in the tumor ascites of these patients (↗ Tregs, TAMS CD163high CD206high CCR2high CD86low and ↘ NK and CD8 + cytotoxic). In addition, we showed a positive correlation between the expansion of these intermediate monocytes and tumor development within the peritoneum. Together, these data highlight the role of blood monocytes as a predictive signature of immune status and tumor development within the peritoneum in patients with ovarian cancer
Del, Bano Joanie. "Développement d'anticorps bispécifiques pour l'immunothérapie des cancers." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0161.
Full textMounting evidence of the key contribution of NK cells in immunity against cancer has boosted the investigations on NK cell-based therapies. Among these strategies, monoclonal antibody-based therapeutics (mAbs) are currently the fastest growing segment of the medicine market. Despite therapeutic innovations, triple negative breast cancers (TNBC) remain insensitive to the current targeted or hormono-therapies. Our objective is to manipulate NK cell functions and tumor targets using an original format of nanobody-based bispecific antibodies (bsFab) to revert the dampened immune response for treating TNBC. Thus, we generate two bsFabs able to crosslink NK and tumor cells. NK antitumor effects driven by mAbs and bsFabs, alone or in combination, were investigated in vitro and in vivo on preclinical TNBC models. Here, we demonstrate the potential of bsFabs to enlarge the number of patients eligible for breast cancer immunotherapy and prompt to consider combination strategies
Ghidouche, Abderrezak. "Nectine-4 : nouvelle cible dans l'immunothérapie du cancer du sein." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20677.
Full textNectin-4 is a cell surface adhesion molecule, member of the Ig-superfamily, and is localized at adherens junctions. Nectin4 is expressed during embryogenesis but not in adult tissues, except in the skin. Mutations in nectin-4 gene in humans cause the EDSS syndrome that affects skin development (EctoDermal and Syndactly Syndrome). We and others have recently demonstrated that nectin-4 expression was a tumoral marker of breast, lung and ovarian carcinoma. We thus started to investigate the functional role of nectin-4 overexpression in breast cancer. Using in vitro and in vivo assays, the preliminary results demonstrate that nectin-4 increased the tumorigenicity of malignant cells.Altogether, these results suggest that nectin-4 might be a candidate target forimmunotherapy (vaccination and antibody based therapy). Using a multiplex approachbased on biochemical, cellular and algorithmic assays, five relevant nectin-4 epitopes were identified. Specific cytotoxic T lymphocyte (CTL) populations from healthy donors that recognized and lyzed peptide-pulsed HLA-A*0201 tumor cells were identified. HLAA*0201-restricted CTL that recognized the N4-145 (VLVPPLPSL) nectin-4 epitope was characterized extensively. This CTL kills breast tumor cells that express nectin4, strongly demonstrating that this peptide could be naturally processed and recognized by specific CTL. In parallel, we also tested a blocking monoclonal antibody against the extracellular region of nectin-4. We next demonstrated that this antibody reduced the metastatic capacity of tumors expressing nectin4. To summarize, in this study, we identified nectin-4 as a newcell surface Tumor Associated Antigen and demonstrated its likely implication in cancertumorigenesis. In parallel, we have developed the specific tools required to conduct an effective immunotherapy targeting nectin4 over-expressing cells, which are currently under investigation
Cavdarli, Sumeyye. "Deciphering biosynthesis mechanisms of O-acetylated GD2 in breast cancer." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1S100.
Full textO-Acetylated GD2 (OAcGD2) ganglioside is neo-expressed in neuroectodermal derived tumors as neuroblastoma and breast cancer. This oncofetal marker is an essential target for immunotherapy. Dinutuximab (Unitixin TM), a therapeutic antibody targeting GD2 has recently obtained Food Drug Administration and European Medicines Agency approval for neuroblastoma treatment. Nevertheless, Dinutuximab causes toxicity due to the expression of GD2 on peripheral nerve fibers. In that way, targeting OAcGD2 seems more beneficial because of absence of this antigen in normal tissues. The activities of OGD2 Pharma Company, partner of this project, are focused on therapeutic antibody development against OAcGD2. OGD2 Pharma developed an antibody specifically targeting OAcGD2 with no cross reaction with GD2. Absent from the normal mammary gland, complex gangliosides especially GD2 and its O-acetylated form have been detected in breast cancer. This expression is correlated with poor patient outcome. The aim of this thesis project was to decipher the molecular mechanisms of OAcGD2 biosynthesis, expression and its role in breast cancer, in order to highlight the therapeutic and diagnostic value of targeting OAcGD2 in breast cancer
Arnould, Laurent. "Apport de l'immunohistochimie à la compréhension des mécanismes de régression tumorale au cours des traitements immunologiques des cancers : à propos de deux modèles." Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOMU03.
Full textIn the developed countries, colorectal and breast cancers are two of the most common malignancies. When the diagnosis is made at the beginning of the disease, surgery, associated or not with radiotherapy may cure the patients. For tumors that present some pejorative prognostic factors,for locally advanced tumors or for metastasic disease, chemotherapy has to be prescribed. However, in these 2 types of cancer, chemotherapy is not able to cure patients suffering from metastasic stage and alternative treatments as immunotherapy or targeted therapies are studied or are still validated.Our work was based on 2 different models of immunotherapy in 2 types of cancer. In an experimental model of carcinomatoses of colorectal cancer in rats, Lipid A injections are able to cure all the rats, even at a macroscopic stage and in half of the women affected by locally advance HER2-overexpressing breast cancer, trastuzumab based preoperative treatment are able to obtain the total disappearance of the tumor. When we look on tumor samples obtained in these two models, we can show that histology and even more immunohistochemistry are able to propose some mechanisms of regression of the tumors. In the rat model, we can show the role of nitric oxide, apotosis, dendritic cells and macrophages and in the breast cancer regression, we show the role of NK cells and ADCC. Theses works show that immunohistochemistry, even if insufficient, may propose some interesting hypotheses that have to be confirm by other experimentations
Turini, Marc. "Développement d'anticorps bispécifiques de lama pour le traitement de cancers du sein réfractaires à l'action du trastuzumab." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM4021.
Full textTrastuzumab is established as standard of care for the treatment of HER2high breast cancers. However, in addition to Fc-related limitations inherent to IgG antibodies, trastuzumab is inefficient to treat low- (triple-negative) or moderate-HER2-overexpressing (hormone-receptor-positive) breast cancers. Based on the unique structural and functional properties of llama single domain antibodies (sdAbs), we report the design of two Fab-like bispecific antibodies targeted to HER2 (HER2bsFab) and mesothelin (MesobsFab), an antigen overexpressed in several human tumors, including triple-negative breast cancers. The two bsFabs display a unique, specific and high affinity for FcγRIII. As a consequence, they do not bind the FcγRIIB inhibitor receptor and bypass competition with endogenous IgGs. HER2bsFab mediated ADCC at picomolar concentration against HER2high as well as HER2moderate cell lines. In vivo HER2bsFab potently inhibited HER2high tumor growth and more importantly, exhibited a net superiority over trastuzumab at inhibiting HER2moderate tumor growth. Moreover, FcγRIIIA-engagement by HER2bsFab was independent of FcγRIIIA-158 polymorphism and induced a stronger NK cells activation in response to target cell recognition. Such findings led us to investigating the efficacy of bsFabs in a context of low-HER2-overexpression displays by triple-negative breast cancers. In vitro characterization showed that both HER2bsFab and MesobsFab trigger efficient lysis of two different triple-negative breast cancer cell lines. Altogether, these findings would enable the treatment of a broader population of patients than that eligible with current HER2-targeted therapies
Faget, Julien. "Les lymphocytes T CD4 régulateurs dans le cancer du sein, recrutement, enrichissement par les cellules dendritiques plasmacytoïdes et impact de l'axe de co-stimulation ICOS/ICOSL." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00981636.
Full textHérault, Aurélie. "Régulation ciblée des cellules myéloïdes dans la moelle osseuse et activation accrue des lymphocytes T dans les tumeurs mammaires pour une amélioration des traitements anticancéreux." Electronic Thesis or Diss., Strasbourg, 2025. http://www.theses.fr/2025STRAJ003.
Full textIn this study, we identified NKG2D as a promising therapeutic target due to its high expression on a large proportion of CD8+ T lymphocytes infiltrating tumors in breast cancer. This expression is associated with better survival in patients with triple-negative breast cancer treated with atezolizumab. Therefore, we developed bispecific antibodies, both human and murine, called HER2-CRB, with one arm targeting HER2 and the other acting as an agonist for NKG2D. We observed that HER2-CRB could form immunological synapses, induce cytokine production, and increase the cytotoxicity of NK cells and CD8+ T lymphocytes stimulated by HER2-TDB. HER2-CRB was effective in humanized and immunocompetent mouse models, in combination with TDBs, improving the effector function of NK cells and CD8+ T lymphocytes. HER2-CRB is capable of activating NK cells and CD8+ T lymphocytes, thereby enhancing antitumor activity and offering broad potential for combination with immunotherapies.Despite the increase in T cell activity, however, we observe several resistance mechanisms. The presence of certain types of myelocytic cells contributes to these mechanisms, making it necessary to better understand their production and regulation. Although blood production is well understood in many ways, the spatial organization of myeloid differentiation within the bone marrow remains unclear. In this study, we used imaging to track the behavior of granulocyte/macrophage progenitors (GMPs) in mice during emergency and leukemic myelopoiesis. Under normal conditions, individual GMPs are scattered throughout the bone marrow. However, during regeneration, we observed that expanding GMP clusters group into distinct clusters, which then locally differentiate into granulocytes. The regulated release of key signals from the bone marrow niche (SCF, IL-1β, G-CSF, TGFβ, and CXCL4) and activation of a progenitor renewal network involving Irf8 and β-catenin induce the transient formation of these GMP clusters during regeneration. In leukemia, GMP clusters are continuously generated due to the persistent activation of the renewal network and the absence of termination cytokines that would normally restore the quiescence of hematopoietic stem cells
Vidil, Carole. "Synthèses et évaluations biologiques de phosphonates analogues du mannose 6-phosphate, substrats potentiels du récepteur mannose 6-phosphate." Montpellier 2, 1997. http://www.theses.fr/1997MON20247.
Full textHamdaoui, Bassou. "Inhibiteurs de la cathepsine D : synthèse et évaluation biochimique de phosphomannosyles associés à la pepstatine A." Montpellier 2, 1993. http://www.theses.fr/1993MON20003.
Full textJabrane-Ferrat, Nabila. "REGULATION DE L'EXPRESSIONDES GENES DU COMPLEXE MAJEURD'HISTOCOMPATIBILITE DE CLASSE II." Habilitation à diriger des recherches, Université Paul Sabatier - Toulouse III, 2003. http://tel.archives-ouvertes.fr/tel-00092605.
Full textLors de mon travail post-doctoral à l'université de Californie San Francisco, j'ai travaillé sur les aspects moléculaires de la régulation de l'expression des gènes du complexe majeur d'histocompatibilité de classe II (CMHII).
Dans une première phase nous avons définit les aspects structuraux des gènes CMHII et leur niveau de méthylation et du compactage de la chromatine. Nous avons montré que MDBP forme un complexe avec la boîte X du DRA et que le complexe MDBP qui est équivalent à l'activité EF-C (protéine qui se lie sur la séquence enhancer du virus du polyome), EP (protéine qui se lie sur la séquence enhancer de l'hépatite B) et MIF (une séquence intronique de c-myc) contient RFX-1 (Zhang, Jabrane-Ferrat et al. 1993).
Ensuite, j'ai montré que la boîte pyrimidine tract contenait une séquence GGAAG présente dans les séquences consensus reconnues par la famille de protéines de l'oncogène Ets-1. Ainsi, j'ai démontré le rôle de l'oncogène Ets-1 dans l'expression d'un taux élevé des gènes du CMH II dans les cellules B et les cellules dendritiques. Ce travail a été publié dans MCB (Jabrane-Ferrat et al. 1994).
En plus de la séquence TATA, le promoteur HLA-DRA possède une séquence Octamer qui fixe les facteurs Oct1 (expression ubiquitaire) et Oct2 (expression spécifique aux cellules B). Les mutations du site TATA ne semblent pas affecter l'expression du promoteur, alors que toutes mutations du site octamer réduisent l'expression du promoteur. Nous avons substitué la séquence Octamer-TATA par la boîteTATA de l'adénovirus E1b et montré que cette mutation par substitution enlève la dépendance du site octamer. Nous avons également montré que la boîteTATA de E1b fixe le facteur TBP, tandis que celle du promoteur DRA ne le fixe pas. Cela nous a permis de conclure qu'au niveau du promoteur HLA-DRA, la boîteTATA n'est pas fonctionnelle et que la séquence Octamer joue un rôle dans le recrutement du TBP à la machinerie de transcription basale (TBP, Pol II et TAFs) (Voliva, Jabrane-Ferrat and Peterlin 1995).
Après clonage du facteur OCA-B, activateur spécifique des cellules B qui interagit de façon équivalente avec les protéines Oct-1 et Oct-2 liée au site octamer, nous avons décrit la première interaction entre deux co-activateurs tissu-spécifiques: CIITA et OCA-B. Nous avons montré que le CIITA et OCA-B interagissent directement et agissent de facon synergique au niveau du promoteur HLA-DRA. Nos résultats suggèrent qu'au niveau des promoteurs de classe II le CIITA permet de recruter un second activateur OCA-B ceci permet d'exposer deux surfaces d'activation pour une interaction avec les TAFs (TBP associated factors [12]) et la machinerie de transcription de base. Ou encore que OCA-B via son interaction avec TBP et d'autres TAFs créerait un complexe qui fixerait le CIITA avec une plus grande affinité et activerait la transcription avec une plus grande éfficacité. La formation d'un complexe multiprotéique entre les protéines régulatrices et le complexe de préinitiation serait responsable de l'expression des gènes de classe II et probablement d'autres gènes impliqués dans la réponse immunitaire. L'absence de l'expression d'OCA-B dans les cellules traitées par l'IFN-g pourrait-être responsable en partie du faible niveau d'expression des gènes de classe II dans les cellules présentatrices d'antigènes et dans les cellules somatiques (Fontes, Jabrane-Ferrat et al. 1996).
Des observations préliminaires nous ont permis de postuler que la boîte S est une duplication ancestrale de la boîteX. Dont le but de confirmer ce postulat, j'ai montré que la délétion de la boîte S est nécessaire à l'expression du promoteur DRA dans les cellules B et que les promoteurs du CMHII sont soumis à des contraintes spaciales très rigides. L'espace entre les boîtes S et X ne peut pas être modifié. De plus nous travaux nous permis de suggérer que non seulement les séquences X et S fixent la même protéine mais en plus il existe des interactions entre les protéines se fixant au niveau de la boîte X et au niveau de de la boîte S (Jabrane-Ferrat et al. 1996).
Pour confirmer que le rôle de la boîte S in vivo et déterminer son importance dans la régulation de l'expression des gènes CMHII, nous avons montré que RFX1 peut lier la séquence X en l'absence des autres séquences promotrices. La présence de la boîte Y permet de favoriser et d'augmenter la fixation de RFX5 par rapport à celle de RFX1. La boîte S quand à elle, elle augmente la fixation de RFX1 et de RFX5. Nos résultats ont suggéré que les boîtes S et Y permettent de sélectionner spécifiquement RFX5 (Fontes, Jabrane-Ferrat et al. 1996 et 1997).
L'ensemble des travaux résumés ici sont repris en détail dans ce mémoire d'habilitation à diriger des recherches.
EXPOSE DES TRAVAUX DE RECHERCHE
I. INTRODUCTION
Les gènes du complexe majeur d'histocompatibilité de classe II (CMHII) ainsi que ceux nécessaires à la dégradation et à la présentation de l'antigène sont régulés de manière coordonnée dans les cellules. Leurs promoteurs contiennent des séquences régulatrices en cis (CUS) qui lient les complexes protéiques composés du facteur régulateur X (RFX) et le facteur nucléaire Y (NFY) (Reith et al. 2000, revue). Ces facteurs sont non seulement recrutés au niveau du promoteur de manière coopérative mais ils forment également une plateforme capable de recruter le trans-activateur du CMHII (CIITA). Le recrutement de CIITA permet ainsi l'initiation et l'élongation de la transcription des gènes du CMHII localisés sur le bras court du chromosome 6 (Fontes et al. 1999, Kanazawa et al. 2000). Notre compréhension, de ce système de régulation, a été favorisée par des analyses génétiques et biochimiques du syndrome du lymphocyte nu (BLS) (Gricelli et al. 1989, Lisowska-Gropierre et al. 1994) dont les patients ont été répértoriés en différents groupes de complémentation. Les mutations responsables de cette immunodéficience, ont été identifiées pour quatres groupes de complémentation et affectent les trois sous-unités de RFX (Steimle et al. 1995, Masternak et al. 1998, Nagarajan et al. 1999) ainsi que le CIITA (Steimle et al. 1993). Dans le dernier groupe (5eme) de BLS, seuls les promoteurs en direction du télomère sont transcrits et par conséquent ils se traduisent par l'absence d'expression de certains isotypes du CMHII. La transcription des gènes impliqués dans la dégradation et la présentation de l'antigène par les déterminants du CMHII est une nécessite absolue pour une immunité adaptative. L'équipe que je souhaite créer aura pour but de pousuivre la dissection des mécanismes moléculaires qui permettent les interactions ADN-protéines et protéine-protéine au niveau du promoteur, leurs fonctions, la régulation du CIITA et sa capacité à coordonner différentes activités de l'ARN polymerase II (ARNPII), recréer ce complexe de régulation dans un système de transcription in vitro. Notre but à long terme est d'utiliser les connaissances que nous allons acquérir pour l'obtention d'un vaccin anti-tumoral.
Moussel, François. "L'interleukine-2 en immunothérapie anticancéreuse." Montpellier 1, 1990. http://www.theses.fr/1990MON11125.
Full textFaure, Olivier. "Hsp70 : un antigène du soi pour l'immunothérapie du cancer." Paris 5, 2003. http://www.theses.fr/2003PA05N106.
Full textThe design of a broad application tumor vaccine requires the identification of tumor antigens expressed in a majority of tumors of various origins. The major stress-induccible heat shock protein Hsp70 (a. K. A Hsp72) is frequently overexpressed in human tumors of various histological origin, such as breast, lung, colorectal, cervical carcinoma and osteosarcoma. To assess the value of Hsp70 as a tumor associated antigen, three peptides from Hsp70 were selected for their high affinity for HLA-A*0201. These peptides were able to trigger anti-tumor cytotoxic T lymphocytes "in vivo" in HLA-A*0201-transgenic HHD mice and "in vitro" in HLA-A*0201+ healthy donors. These epitopes are tagets of an immune reponse in many HLA-A0201+ breast cancer patients. Hsp70 is thus a valuable tumor antigen for broad application tumor immunotherapy
Chavanton, Aude. "Optimisation de traitements immunothérapeutiques dans le cancer." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCI005.
Full textCancer is a disease caused by the proliferation of transformed cells that cannot be controlled by the body, ultimately leading to death. Today, it is the leading cause of death in France, making it a major focus of research interest. Despite the wide range of cancer treatments currently available in clinical practice (chemotherapy, radiotherapy, hormone therapy, etc.), many patients do not respond to these therapies, and the death rate is still very high. Some fifteen years ago, immunotherapy took its first clinical steps and demonstrated promising effects, becoming a promising new therapeutic weapon against cancer. Immunotherapy is a therapeutic approach designed to stimulate the immune system to better destroy cancer cells. Anti-PD-1/PD-L1 immunotherapy has shown promising effects in various types of cancer. However, despite their efficacy in some patients, many do not respond to these therapies in multiple cancer types, including colorectal cancer. In this context, the research team in which I carried out my PhD demonstrated that the heat shock protein HSP110 promotes colorectal cancer cell proliferation and is associated with poor prognosis in colorectal cancer. This led to the development of an HSP110 inhibitor molecule called i007. The aim of this thesis work is to evaluate the efficacy of anti-PD-L1/i007 dual therapy in colorectal cancer, and to identify whether HSP110 inhibition can improve the efficacy of anti-PD-L1. We were able to identify an antitumor effect of this dual therapy, probably mediated by depleted CD8+ cells and the secretion of granzyme A, B, interferon γ and perforin. Macrophages, NK cells and mast cells also appear to be involved in the immune response induced by double therapy, but their exact role remains to be defined. Finally, an opening to a possible new project seeking to potentiate the effect of anti-PD-L1 was highlighted, by combining anti-PD-L1 with anti-LAG-3
Dadvar, Ehsan. "Characterization of cancer/testis antigen MAGE-A11 for immunotherapy of prostate cancer." Master's thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/26789.
Full textCancer/testis antigens are ideal targets for cancer immunotherapy because of their limited expression in normal tissues, aberrant expression in malignancies and their immunogenic properties. The aim of this study was to evaluate the potential of cancer/testis antigen, MAGE-A11, as an immunotherapeutic target for development of a prostate cancer vaccine. To accomplish this, we produced the monoclonal antibody 5C4 that is capable of recognizing MAGE-A11 in formalin-fixed paraffin-embedded tissues. We also investigated the expression of MAGE-A11 in a wide variety of cancer cell lines to determine the scope of its expression in cancer. It was shown that MAGE-A11 is widely expressed in malignancies. The highest MAGE-A11 expression was observed in colon cancer and astrocytoma brain tumors. Finally, we identified three naturally processed MHC class II HLA-DR1 epitopes in MAGE-A11 protein, thus confirming its immunogenicity and its potential as a target for cancer immunotherapy.
Lapointe, Jacques. "Androgènes et cancer du sein." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ57940.pdf.
Full textTEISSEYRE, MONIQUE. "Le cancer intervallaire du sein." Montpellier 1, 1992. http://www.theses.fr/1992MON11220.
Full textREBENA, DUBOIS CATHERINE. "Alimentation et cancer du sein." Lille 2, 1990. http://www.theses.fr/1990LIL2M275.
Full textDuffour, Marie-Thérèse. "Immunisation antitumorale à l'aide d'un vecteur adénoviral codant pour l'antigène de tumeur P815A." Paris 5, 1998. http://www.theses.fr/1998PA05P074.
Full textDiest, Paul J. van Baak Jan P. A. "Quantitative cyto- and histoprognosis in breast cancer /." Amsterdam ; London ; New York [etc.] : Elsevier, 1992. http://catalogue.bnf.fr/ark:/12148/cb373728109.
Full textThèse soutenue par P. J. van Diest. Bibliogr. à la fin de chaque chap. Index.
Laroche, Adrien. "Un nouveau type d'anticorps bispécifique avec une activité de déplétion ciblée de facteurs solubles pro-tumoraux du microenvironnement tumoral pour la thérapie du cancer." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTT047.
Full textThe objective of this thesis is to design a new type of bispecific therapeutic antibodies to selectively eliminate soluble pro-tumoral factors from the tumor microenvironment by a sweeping antibody mechanism by targeting the transferrin receptor (TfR1). TfR1 is an overexpressed receptor in many tumors. It allows iron cell supply by a FcRn-like mechanism. The soluble factor chosen for this proof of concept is interleukin (IL-6), a multifunctional cytokine involved in tumor progression. Three different bispecific antibody formats have been developed based on internalizing antagonistic antibodies targeting TfR1 and a pH-dependent non neutralizing anti-IL-6 antibody. We highlight that (1) the 3 formats of bispecific antibodies retain the binding properties to IL-6 (binding at physiological pH but not at acidic pH) and TfR1 of parental antibodies (blocade of holo transferrine internalization) and (2) allow the internalization of IL-6 via TfR1. Sweeping activity was evaluated in vitro, by comparing the inhibitory activities of bispecific antibodies and the combination of parental antibodies on cell lines with IL-6 growth dependent (myeloma XG-6 and XG-7) or not (lymphoma RAJI). IL-6 elimination was also demonstrated in vivo by monitoring IL-6 elimination in the plasma of xenografted mice with an IL-6-producing pancreatic cancer line. The results of this thesis show that it is possible to obtain a TfR1-dependent sweeping activity, which opens up a wide range of therapeutic applications in the targeting of pro-tumor soluble factors by the use of specific TfR1-like tumor receptors
Salavagione, Jean-Marc. "Les cancers intrakystiques du sein." Montpellier 1, 1991. http://www.theses.fr/1991MON11239.
Full textBesancon, Marjorie. "Immunothérapie non-spécifique du cancer de la vessie : développement de nouvelles approches basées sur la combinaison d'agents thérapeutiques." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27996.
Full textBladder cancer (BCa) is the ninth most common cancer in the world, with 430 000 new cases diagnosed in 2014. Muscle-invasive bladder cancer represents about 25% of bladder tumors, while non-muscle-invasive bladder cancer represents about 75% of these tumors. The latter are usually associated with a favorable prognosis but are characterized by a high rate of recurrence and progression while the former are aggressive from the onset and are at high risk of progression toward advanced disease. Among the various therapies available for the management of bladder tumors is non-specific immunotherapy using bacillus Calmette-Guerin (BCG) for the treatment on non-muscle invasive bladder tumors and, more recently, inhibitors of immune checkpoint (IC) for the treatment of advanced bladder tumors. BCa is one of the rare cancers to respond well to immunotherapy but, nevertheless, these treatments are suboptimal. The main objective of my project was to develop new immunotherapeutic approaches to fight more efficiently against BCa. To achieve this, three complementary approaches were investigated in murine BCa models. We first assessed in vitro and in vivo the potential of poly(I:C), a TLR3 agonist, used alone or in combination with BCG. While poly(I:C) induced anti-proliferative and apoptotic effects on BCa cells in vitro, the combination of poly(I:C) and BCG induced in vivo a complete tumor regression in 28% of treated mice. Then, we evaluated the potential of two combinations of IC inhibitors in two murine BCa models. The first combination studied was that of the simultaneous blockade of PD-1 and TIM-3 tested in the MBT-2 model because the characterization of the MBT-2 tumors showed that these two receptors where frequently IC expressed in these tumors. In vivo blockade of these pathways revealed that in MBT-2 tumors, PD-1 is associated to a pro-tumoral activity, whereas, TIM-3 is associated with anti-tumoral activity, revealing opposite functions of these IC in these tumors. The second combination studied was that of PD-1 and LAG-3 tested in the MB49 BCa model. The characterization of MB49 tumors showed that PD-1 and LAG-3 were important IC in these tumors. The in vivo study showed that the simultaneous blockade of PD-1 and LAG-3 increased the survival rate, since 67% of mice showed a complete tumor regression while the survival rates were 33% and 0% when anti-PD-1 and anti-LAG-3, respectively, were used in monotherapy. Finally, since androgens seem to play an important role in BCa, we tested an approach combining the inhibition of PD-1 and of the androgen receptor (AR). We showed that enzalutamide and seviteronel, two second generation antiandrogens, induced in vitro a decrease of the proliferation of human and murine BCa cells. In vivo, the combination of enzalutamide with anti-PD-1 showed a 66% overall survival rate, a rate that is much higher than the 16% rate observed when enzalutamide or anti-PD-1 were used alone. Thus, these studies allowed us to identify various possible ways to increase anti-tumor immune response that could be tested in clinical trials. They also show that the combination of therapeutic approaches is very promising the future of BCa immunotherapy.
Dagdemir, Aslihan Seda. "Paysage épigénétique du cancer du sein." Thesis, Clermont-Ferrand 1, 2014. http://www.theses.fr/2014CLF1MM14/document.
Full textBreast cancer remains the leading cause of cancer-related deaths in women, and is noted for conflicting clinical behaviors and patient outcomes, despite common histopathological features at diagnosis. This can be explained by the high histological and molecular heterogeneity of the disease, making it hard to choose a therapy adapted uniquely to each patient. Epigenetics refer to changes in phenotype and gene expression. Epigenetic modifications of the genome can be acquired de novo and are potentially inherited. Epigenetic mechanisms work to change the accessibility of chromatin to transcriptional regulation locally and globally via modifications of the DNA and by modifications or rearrangements of nucleosomes. Epigenetics consist in several molecular mechanisms: histone modifications, small non-coding or antisense RNAs and DNA methylation that are closely interconnected. The incidence and mortality of breast cancer is high in the Western world as compared with countries in Asia. There are also differences in the regional cancer incidence rates in Western countries. Several studies involving immigrants to Western countries suggest that lifestyle and diet are two of the main causes of these differences. In Eastern countries, the incidence of breast cancer is approximately one-third that of Western countries, whilst their high dietary intake of phytoestrogens, mainly in the form of soy products, can produce circulating levels of phytoestrogens that are known experimentally to have estrogenic effects. An increasing number of epidemiological and experimental studies have suggested that the consumption of a 4 phytoestrogen-rich diet may have protective effects on estrogen-related conditions, such as breast cancer.Based upon this information, we studied the effects of treatment phytoestrogens; genistein, daidzein and 17-β-estradiol on the post-translational modification of histones such as lysine methylation and acetylation of histones H3 and H4 in breast cancer cell lines. Subsequently, we studied the effects of histone methylation inhibitor and histone deacetylase inhibitor on histone lysine trimethylation and acetylation in breast cancer cell lines. For this study, we used two breast cancer cell lines MCF-7 and MDA-MB-231. Each cell line was treated respectively with 3-Deazaneplanocin A hydrochloride (DZNep) [5 μM] (HMTi), Sodium Butyrate (NaBu) [2 mM] (HDACi) and Suberoylanilide Hydroxamic acid (SAHA) [1 μM] (HDACi) for 48 hours. Finally, we completed studies in all cell lines with breast tumors to assess Chromatin ImmunoPrecipitation (ChIP) of selected histone modifications in cancer. The relative levels of three modified histones, including H3K27me3 (Histone 3 Lysine 27 Methylation), H3K9ac (Histone 3 Lysine 9 Acetylation), and H3K4ac (Histone 3 Lysine 4 Acetylation) will be determined in breast tumors compared to matched normal tissue according to the classification of Saint Gallen. Today, ChIP has been coupled with promoter DNA microarrays to evaluate the mechanisms of human gene regulation on a genome-wide scale. ChIP-on-chip technology could be used to investigate the alterations of global gene expression in tumorigenesis. Here, we investigated differentially expressed genes associated with modified histones H3K27me3, H3K9ac and H3K4ac in breast tumors by Agilent SurePrint G3 400kX2 microarrays containing approximately 21,000 of human transcripts. We will scan the enriched regions at each gene promoter in thirty breast tumors compared with normal tissue samples. Breast tumor samples will be classified according to their clinical profiles, especially hormone receptor status
Bonhomme, Philippe. "Aspects dermatologiques du cancer du sein." Bordeaux 2, 1995. http://www.theses.fr/1995BOR23098.
Full textBENGHANEM, FIRDAOUS LOUBNA. "Taxol et cancer du sein avance." Nantes, 1993. http://www.theses.fr/1993NANT038M.
Full textSPORTES-GERBAULT-SEUREAU, MICHELE. "Etude cytogenetique du cancer du sein." Paris 6, 1988. http://www.theses.fr/1988PA066688.
Full textMARCUZZI, LEJAY ISABELLE. "Cancer du sein : l'information en questions." Lille 2, 1994. http://www.theses.fr/1994LIL2M030.
Full textDarwiche, Jihad. "Grossesse apres cancer du sein traite." Aix-Marseille 2, 1993. http://www.theses.fr/1993AIX20027.
Full textAlibert, Didier. "Le cancer du sein chez l'homme." Dijon, 1994. http://www.theses.fr/1994DIJOM051.
Full textLécuru, Fabrice. "Le cancer du sein chez l'homme." Lille 2, 1991. http://www.theses.fr/1991LIL2M278.
Full textBERTON, DOMINIQUE. "Predisposition hereditaire et cancer du sein." Nantes, 1993. http://www.theses.fr/1993NANT257M.
Full textCalmels, Bastien. "Immunothérapie non-spécifique et immuno-monitoring pour le traitement du cancer." Paris 7, 2004. http://www.theses.fr/2004PA077185.
Full textDecobert, Marc. "Facteurs prédictifs de l'issue de l'immunothérapie au BCG des tumeurs superficielles de la vessie." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24953/24953.pdf.
Full textZennadi, Rahima. "Immunothérapie des cancers colorectaux : contribution à l'étude de quelques problèmes." Nantes, 1992. http://www.theses.fr/1992NANTO9VS.
Full textHaensler, Patrick. "Cancer du sein chez l'homme (caractéristiques épidémiologiques, cliniques, thérapeutiques et génétiques à partir de 40 cas traités au C. R. L. C. De Montpellier)." Montpellier 1, 1996. http://www.theses.fr/1996MON11083.
Full textEspitalier, Marion. "Les cancers inflammatoires du sein PEV3 (ou mastites carcinomateuses) : méthodes et résultats thérapeutiques de 1976 à 1981 au CLRC de Montpellier." Montpellier 1, 1988. http://www.theses.fr/1988MON11050.
Full textBERNARD, JONARD GENEVIEVE. "Evenement de vie et cancer du sein." Lyon 1, 1990. http://www.theses.fr/1990LYO1M372.
Full textFleury-Ricordeau, Laurence. "Modifications épigénétiques dans le cancer du sein." Toulouse 3, 2008. http://thesesups.ups-tlse.fr/301/.
Full textIn breast cancer, approximately one third of tumors express neither the estrogen receptor (ERa) nor estrogen regulated genes such as the Progesterone Receptor gene (PR). Our study provides new insights into the mechanism allowing hormone-activated expression of ERa target genes silenced in ERa-negative mammary tumor cells. In cell lines derived from ERa-negative MDA-MB231 cells, stable expression of different levels of ERa from a transgene did not result in transcription of PR. A quantitative comparative analysis demonstrates that inhibiting DNA methyltransferases using 5-aza-2'-deoxycytidine or specific disruption of DNMT1 by small interfering RNAs and treatment with the histone-deacetylase inhibitor Trichostatin A enabled ERa-mediated hormone-dependent expression of endogenous PR. We show that demethylation of a CpG island located in the first exon of PR was a prerequisite for ERa binding to these regulatory sequences. Although not a general requirement, DNA demethylation is also necessary for derepression of a subset of ERa target genes involved in tumorigenesis. PR transcription did not subsist four days after removal of the DNA methyltransferase blocking agents, suggesting that hormone-induced expression of ERa target genes in ERa-negative tumor cells is transient. Our observations support a model where an epigenetic mark confers stable silencing by precluding ERa access to promoters
Theillet, Charles. "Anomalies génomiques dans le cancer du sein." Montpellier 2, 1990. http://www.theses.fr/1990MON20062.
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