Dissertations / Theses on the topic 'ZNF318'

Muscle atrophy is a feature of many chronic diseases and contributes to both morbidity and mortality, emphasising the importance of understanding the molecular pathways involved. Zinc finger protein 216 (ZNF216) is an atrogene, a gene which is up-regulated during and directly mediates skeletal muscle atrophy, and encodes the ubiquitin (Ub) receptor protein ZNF216. Herein it is demonstrated that ZNF216 mRNA levels increase in the extensor digitorum longus (EDL) in a lipopolysaccharide (LPS)-infusion rat model of muscle atrophy, relative to saline control. However, combined administration of low level dexamethasone (Dex) with LPS, although sparing muscles from atrophy, did not blunt ZNF216 expression which parallels previous observations for the atrogenes muscle atrophy F-box protein (MAFbx) and muscle RING-finger 1 (MuRF1). ZNF216 expression levels were further elevated in biceps femoris muscle in rats dosed with the statin drug simvastatin (in which severe muscle damage and atrophy occurs), relative to control rats. The ZNF216 protein’s Ub-binding ability and its reported association with the 26S proteasome indicates it may shuttle proteins targeted for degradation to the proteasome as part of the atrophy programme. We utilised immobilised recombinant ZNF216 protein and its Ub-binding Znf_A20 domain alone to capture Ub-modified proteins from rat skeletal muscle that may represent ZNF216’s substrates. Bound proteins specifically eluted by deubiquitination were identified via liquid chromatography tandem mass spectrometry (LC-MS/MS) and included adenylate kinase 1 (AK1) and actin, both previously proposed as substrates of MuRF1. However, ion scores for all candidates were below the accepted threshold of significance and immunoblotting failed to validate LC-MS/MS data. This approach also revealed an increase in a low molecular weight Ub-positive protein from EDL muscle after 24hrs of LPS infusion. Retrospective analysis revealed this Ub-positive protein was consistently captured in other experiments and confirmed by protein MS and immunoblotting to represent an unmodified and unanchored (i.e. not attached to a substrate) K48-linked Ub dimer. Subsequent capture of the Ub dimer using the Znf_UBP domain of isopeptidase T (isoT), a Ub-binding domain selective for the free C-terminus of Ub, confirmed the dimer was unanchored and also revealed a ladder of longer endogenous unanchored poly-Ub chains. Optimised affinity capture conditions has afforded the first opportunity to purify longer free poly-Ub chains and perform the initial molecular analyses of endogenous unanchored poly-Ub purified from in vivo sources.

The vast majority of colorectal cancer (CRC)-related deaths is caused by the metastatic spread of tumor cells to distant organs rather than by the growth of the primary tumor. However, until today the mechanisms involved in CRC metastasis are not completely understood. For cancer cells the epithelial-mesenchymal transition (EMT) is thought to represent a prerequisite to invade adjacent tissue and form metastases at distant sites. Transcription factors, cytokines or oncogenic signaling pathways play an important role in the regulation of the EMT program. Recently, the oncoprotein c-MYC was shown to induce EMT, e.g. by enhancing SNAIL expression. Previously an interaction between c-MYC and the transcription factor ZNF281/ZBP-99 has been described. However, so far it remained elusive which upstream signals regulate ZNF281 levels or activity and furthermore, what functions are mediated by ZNF281, which may contribute to the c-MYC-mediated tumor progression. Here, it could be shown that SNAIL and miR-34a/b/c control the expression of ZNF281 in a coherent feed-forward-loop: the EMT-transcription factor SNAIL directly induced ZNF281 transcription and repressed miR-34a/b/c, thereby alleviating ZNF281 from direct down-regulation by miR-34. Moreover, p53 activation led to a miR-34a-dependent down-regulation of ZNF281 expression. Additionally, in CRC cells it could be demonstrated, that ectopic ZNF281 expression induces EMT. This process was mediated by and dependent on the direct induction of SNAIL. Furthermore, ectopic ZNF281 increased migration/invasion, and enhanced β-catenin activity. Expression of the stemness markers LGR5 was directly and CD133 indirectly induced by ectopic ZNF281 expression, which also increased sphere formation. Conversely, in CRC cells the experimental down-regulation of ZNF281 resulted in a mesenchymal-epithelial transition (MET), inhibited migration/invasion and decreased sphere formation. Additionally, repression of ZNF281 led to decreased formation of lung metastases by CRC cells in a xenograft mouse tumor model. Furthermore, ZNF281 protein expression was indirectly elevated by ectopic c-MYC expression. Inactivation of ZNF281 prevented the induction of EMT by c-MYC or SNAIL. The analysis of tumor samples revealed that ZNF281 expression increases during CRC progression and correlates with tumor recurrence. Taken together, the results identify ZNF281 as a new EMT-promoting transcription factor, which contributes to metastasis formation in CRC. In the future, this knowledge may be exploited for therapeutic and diagnostic purposes in cancer therapy.

ZNF217 est un oncogène potentiel codant pour un facteur de transcription Krüppel-like. Cette étude vise à explorer le rôle délétère et la valeur pronostique de ZNF217 dans le cancer du sein. Nos résultats ont montré que : (i) des niveaux d'expression élevés de ZNF217 (tant au niveau de l'ARNm qu'au niveau protéique) sont associés à un mauvais pronostic chez les patientes atteintes d'un cancer du sein, et plus particulièrement dans les cancers du sein de type ER+/Luminaux/Luminaux A ; (ii) ZNF217 induit la transition épithélio mésenchymateuse (EMT) dans les cellules épithéliales mammaires humaines via la voie de signalisation du TGF-beta ; (iii) ZNF217 induit un phénotype agressif dans les cellules cancéreuses mammaires se traduisant in vitro par la stimulation de la croissance indépendante de l'ancrage, de la migration et de l'invasion cellulaire ; (iv) ZNF217 stimule la croissance tumorale et le développement spontané de métastases chez la souris ; (v) ZNF217 se lie à ERalpha et augmente l'activité transcriptionnelle ligand-dépendante de ce dernier en favorisant le recrutement d'ERalpha sur les éléments de réponse aux oestrogènes (EREs) ; (vi) ZNF217 stimule la formation de mammosphères dans des lignées cellulaires de cancer du sein ER– ou ER+ ; (vii) ZNF217 induit la résistance à l'hormonothérapie (tamoxifène) dans des cellules cancéreuses mammaires ER+ ; (viii) des niveaux élevés d'expression de ZNF217 sont associés à un mauvais pronostic en terme de survie sans récidive chez les patientes atteintes d'un cancer du sein et traitées par hormonothérapie uniquement. Nos résultats suggèrent que l'expression de ZNF217 représente un nouveau et puissant biomarqueur pronostique dans le cancer du sein ER+/Luminal/Luminal A, permettant la re-stratification de ces cancers du sein dits « de bon pronostic », pour lesquels il n'existe pas à l'heure actuelle de biomarqueurs permettant de les identifier. En conclusion, ZNF217 représente une nouvelle cible thérapeutique pour le traitement personnalisé des patientes atteintes d'un cancer du sein et exprimant de forts niveaux d'expression de ZNF217, en particulier les patientes ER+/ZNF217+
ZNF217 is a candidate oncogene encoding for a Krüppel-like transcription factor. This study aims at exploring deeper insights on deleterious roles of ZNF217 and the prognostic significance of ZNF217 expression in breast cancers. We found that: (i) high levels of ZNF217 expression (at both mRNA and protein levels) are associated with poor prognosis in breast cancer patients, more particularly in ER+/Luminal/Luminal A breast cancers; (ii) ZNF217 induces epithelial-mesenchymal transition (EMT) in human mammary epithelial cells via the TGF-beta-activated Smad signaling pathway; (iii) in vitro ZNF217 stimulates several aggressive phenotypes in breast cancer cells, including anchorage-independent growth, cell migration and invasion; (iv) ZNF217 stimulates tumor growth and promotes the development of metastases in vivo; (v) ZNF217 binds with ERalpha and enhances 17beta- estradiol (E2)-induced ERalpha transactivation by increasing the recruitment of ERalpha to estrogen-responsive elements (EREs); (vi) ZNF217 increases mammosphere formation in ER– or ER+ breast cancer cell lines; (vii) ZNF217 confers resistance to endocrine therapy (tamoxifen) in ER+ breast cancer cells, and (viii) high levels of ZNF217 expression are associated with shorter relapse-free survival (RFS) in breast cancer patients treated with endocrine therapy only. Our findings suggest that ZNF217 expression represents a novel and powerful prognostic biomarker in ER+/Luminal/Luminal A breast cancers, allowing the re-stratification of these “good prognosis” breast cancers, which are currently not further classified by any other biomarkers available. In conclusion, ZNF217 could be a potential therapeutic target for a personalized treatment strategy in patients overexpressing ZNF217, in particular in ER+/ZNF217+ patients

Interferon regulatory factor-1 (IRF-1) is a transcription factor and tumour suppressor, involved in many diverse cellular processes including immune responses and growth regulation. An interesting feature of IRF-1 is that it can both activate and repress gene expression, possibly by acting with co-activator or co-repressor proteins. In a previous phage display assay, a homologous peptide to the known repressor protein, zinc finger 350 (ZNF350), was found to bind to the C-terminus of IRF-1. ZNF350, also known as ZBRK1 (Zinc finger and BRCA1-interacting protein with KRAB domain-1), is a member of the Krüppel-associated box (KRAB)-containing zinc finger (KZF) proteins, which is a group of the widely distributed transcriptional repression proteins in mammals. ZNF350 has previously been shown to repress the expression of a number of genes including ANG1 and GADD45A, often in complex with other proteins. This study confirms the direct interaction between IRF-1 and ZNF350 and identifies key residues, including the LXXLL repression motif within the C-terminus of IRF-1, necessary for the binding interface. The two proteins have additionally been shown to interact within a cellular environment, shown by using techniques including immunoprecipitation and a proximity ligation assay. In addition, the ZNF350/IRF-1 complex formation appears to occur in the basal state of the cell, as opposed to in response to cellular stress such as viral infection or DNA damage. On the basis of ZNF350 being a negative regulator of transcription, a novel technique was developed to identify putative targets of both ZNF350 and IRF-1. This involved an initial bioinformatics screen using candidate IRF-1 binding site data obtained from CENTIPEDE, an algorithm that combines genome sequence information, with cell-specific experimental data to map bound TF binding sites. This allowed for the identification of novel target genes that contained the ZNF350 consensus binding site, GGGxxCAGxxxTTT, within close proximity to an IRF-1 consensus site, such as the immune response gene IL-12A. Lastly, a peptide phage display screen was combined with high-throughput sequencing to identify other potential binding partners of ZNF350 and perhaps help to understand the mechanism by which transcriptional repression is controlled by complex formation.

ZNF217 est un oncogène codant pour un facteur de transcription de la famille Krüppel-like. Nos objectifs sont d'explorer le rôle de l'oncogène ZNF217 dans le développement de métastases du cancer du sein à tropisme osseux et la valeur pronostique ainsi que les fonctions d'une nouvelle isoforme de ZNF217. Nous avons identifié que de forts niveaux d'expression de l'ARNm de ZNF217 dans les tumeurs primitives du sein pourrait être un indicateur d'un développement ultérieur de métastases osseuses. Nous avons montré que ZNF217 est un nouvel activateur de la voie BMP et que l'inhibition de cette voie permet de reverser les propriétés métastatiques des cellules ZNF217 positives in vitro (migration, invasion et chimiotactisme vers des cellules osseuses). In vivo chez la souris, les cellules ZNF217-positives de cancer du sein développent très rapidement des métastases ostéolytiques. Dans notre deuxième axe de travail, nous avons prouvé l'existence de l'isoforme ZNF217-?E4 et montré qu'elle possède une valeur de mauvais pronostic dans le cancer du sein ER-a+. Les cellules surexprimant ZNF217-?E4 développent un phénotype encore plus agressif que les cellules possédant la forme WT (prolifération, résistance au paclitaxel), et de manière intéressante, ZNF217-?E4 semble jouer un rôle de régulateur de l'expression de ZNF217-WT. En conclusion, ZNF217 et/ou la voie BMP pourraient représenter des cibles thérapeutiques dans le traitement des cancers du sein ZNF217-positif
ZNF217 is an oncogene encoding for a Krüppel-like transcription factor. Our aims were to explore the roles of the ZNF217 oncogene in the development of breast cancer metastases to the bone and to decipher the prognostic value and the functions of a new ZNF217 isoform. Our work identified that high ZNF217 mRNA expression levels within the primitive breast tumor could represent an indicator for future recurrence to the bone. Further in vitro experiment demonstrated that ZNF217 is a new activator of the BMP pathway and that the inhibition of this pathway could inhibit the metastatic properties of ZNF217-positive breast cancer cells in vitro (migration, invasion, chemotaxis to bone cells). In vivo in mice, ZNF217-positive breast cancer cells developed osteolytic metastases very faster. In our second axis, we have proven the existence of the ZNF217-?E4 isoform and we found that this isoform possesses a prognostic significance associated with a poor prognosis in ER-a+ breast cancer. Furthermore, cells overexpressing ZNF217-?E4 developed a more aggressive phenotype than cells overexpressing ZNF217-WT (proliferation, paclitaxel resistance). Interestingly, ZNF217-?E4 seems to play a regulatory role regarding ZNF217-WT expression. In conclusion, ZNF217 and/or the BMP pathway could represent potential therapeutical targets in the management of ZNF217 positive breast cancer

La sopravvivenza degli organismi dipende dall'accurata trasmissione dell'informazione genetica durante i processi che portano alla divisione cellulare. Questa fedele trasmissione richiede non soloun'elevata precisione nella replicazione del DNA e nella perfetta segregazione cromosomica, ma anche la capacità di sopravvivere ai danni al DNA spontanei o indotti minimizzando il numero di mutazioni ereditabili dalle cellule figlie. Le cellule sono constantemente soggette agli effetti citotossici e mutageni degli agenti in grado di causare danno al DNA. Per rispondere e difendersi da questa minaccia, le cellule eucariotiche hanno evoluto dei processi che sono collettivamente catalogati come risposta al danno al DNA (DDR). La DDR è una complessa via di trasduzione del segnale che ha la capacità di riconoscere la presenza di danni al DNA e trasdurre questa informazione nella cellula al fine di attivare i processi di riparo. Infatti, le cellule possiedono diversi enzimi capaci di rimodellare e riparare il DNA, comunque la loro attività deve essere spazialmente e temporalmente regolata per ottimizzare il riparo del DNA e prevenire potenziali e deleterie alterazioni nella struttura del DNA. In questi ultimi anni considerevoli progressi sono stati fatti per delucidare le componenti e i processi che caratterizzano la DDR eucariotica. Nonostante questo, un punto centrale in questo campo di studio rimane l'identificazione dei geni e delle proteine che controllano l'espressione delle proteine coinvolte nella DDR. Di interesse è la recente scoperta di un numero crescente di fattori di trascrizione che in grado di regolare direttamente la riparazione del DNA e che fanno parte come componenti integrali del macchinario di riparo stesso con meccanismi indipendenti dalla loro abilità di promuovere e/o reprimere la trascrizione. Infatti, gli agenti di danno al DNA (radiazioni, chemioterapia, agenti genotossici) sono in grado di promuovere la traslocazione di alcuni fattori di trascrizione direttamente sulle lesioni al DNA, dove partecipano all'attivazione del riparo al DNA. ZNF281 è un fattore di trascrizione appartenente alla tipologia degli "zinc finger" coinvolto nel mantenimento della staminalità cellulare e nei processi di transizione epiteliale-mesenchimale (EMT). In questo studio vengono analizzati i ruoli di ZNF281 durante la DDR. Infatti, riportiamo che l'espressione di ZNF281 aumenta sia a livello di mRNA, che di proteina dopo stress genotossico indotto da agenti chimici che causano danno al DNA (etoposide, doxorubicina, camptotecina) in diversi sistemi quali le cellule tumorali, cellule di cheratinociti primari e nell’epidermide del Mus musculus. Il comet assay dimostra che il riparo al DNA è ritardato nelle cellule silenziate per l'espressione di ZNF281 e trattate con etoposide. Inoltre, l'analisi con RT profiler array ha dimostrato che l'espressione di dieci geni coinvolti nella risposta al danno al DNA è diminuita nelle cellule trattate con etoposide e silenziate per l'espressione di ZNF281. In linea con questa scoperta, XRCC2 e XRCC2, due geni che prendono parte rispettivamente ai processi di ricombinazione omologa (HR) e Non Homologous End Joining (NHEJ), sono trascrizionalmente attivati da ZNF281 attraverso un meccanismo dipendente dal legame al DNA come dimostrato da esperimenti di saggio della luciferasi e di immunoprecipitazione della cromatina (ChIP). Inoltre, ZNF281 è un co-fattore della proteina c-Myc per l'attivazione dell'espressione della nucleolina e della ciclina B1; mentre c-Myc, anche se in grado di legare promotori di XRCC2 e XRCC4, non è capace di promuovere la trascrizione o di modificare l'attività di ZNF281 sui promotori di questi due geni. L'analisi bioinformatica di una coorte di 1971 pazienti affetti da cancro alla mammella rivela una correlazione statisticamente significativa tra l'espressione di ZNF281 e di XRCC2. Inoltre l'analisi proteomica e il proximity ligation assay (PLA) dimostrano che ZNF281 interagisce con DNA-PK, un'importante proteina del processo di DDR, suggerendo per ZNF281, un ruolo indipendente dalla trascrizione. In sintesi, i risultati discussi in questo lavoro, evidenziano per la prima volta il coinvolgimento di ZNF281 nella risposta cellulare a stress genotossici attraverso un controllo esercitato sull'espressione di geni che agiscono in differenti meccanismi di riparo al danno e attraverso la sua interazione con DNA-PK.
The survival of organisms depends on the accurate transmission of genetic information from one cell to its daughters. Such faithful transmission requires not only extreme accuracy in replication of DNA and precision in chromosome distribution, but also the ability to survive spontaneous and induced DNA damage while minimizing the number of heritable mutations. Therefore, cells are constantly under threat from the cytotoxic and mutagenic effects of DNA damaging agents. To respond to these threats, eukaryotes have evolved the DNA damage response (DDR). The DDR is a complex array of different mechanisms that have the ability to sense DNA damage and transduce this information to the cell in order to modulate cellular responses to DNA damage. Cells possess several enzymatic tools capable of remodeling and repairing DNA; however, their activities must be tightly regulated in a temporal, spatial, and DNA lesion-appropriate fashion to optimize repair and prevent unnecessary and potentially deleterious alterations in the structure of DNA during normal cellular processes. During the past several years, considerable progress has been made in elucidating the components and the processes of the eukaryotic DDR. A central issue in this field, which remains to be understood in greater detail, is the identification of the controllers of the expression of DDR proteins. Interestingly, in recent years an increasing number of studies have revealed that several TFs regulate DNA repair directly and can function as integral components of the repair machinery itself in a transcription independent fashion. In fact, DNA damage-inducing insults (irradiation, chemotherapy drugs) promote translocation of some TFs directly to DNA lesions, where they actively facilitate DNA repair. ZNF281 is a zinc finger transcription factor involved in the control of cellular stemness and Epithelial Mesenchymal Transition (EMT). In this study we analyze the roles of ZNF281 during DDR. We report that ZNF281 expression increased after genotoxic stress caused by DNA damaging drugs (Etoposide, Doxorubicin, Camptothecin) in cancer cell lines, normal keratinocytes and in mouse skin in vivo. Comet assays demonstrated that DNA repair was delayed in cells silenced for the expression of ZNF281 and treated with Etoposide. Furthermore, RT profiler array analysis demonstrated that the expression of ten DDR genes was down-regulated in cells treated with Etoposide and silenced for ZNF281. In line with these findings, XRCC2 and XRCC4, two genes that take part in Homologous Recombination (HR) and Non Homologous End Joining (NHEJ) respectively, were transcriptionally activated by ZNF281 through a DNA binding-dependent mechanism as demonstrated by luciferase assays and Chromatin crosslinking ImmunoPrecipitation (ChIP) experiments. In addition, ZNF281 works as a c-Myc co-factor to stimulate the expression of nucleolin and cyclin B1; instead c-Myc, which also binds to the promoters of XRCC2 and XRCC4, was unable to promote their transcription or to modify ZNF281 activity. Bioinformatic analysis of 1971 breast cancer patients disclosed a significant correlation between the expression of ZNF281 and XRCC2. Moreover proteomic analysis and Proximity Ligation Assay (PLA) demonstrated that ZNF281 interacts with DNA-PK, an important protein of DDR, suggesting a transcription-independent role of ZNF281 in DDR. Our data highlight, for the first time, the involvement of ZNF281 in the cellular response to genotoxic stress through the control exercised on the expression of genes that act in different repair mechanisms and through interaction with with corecomponents of DNA repair pathways.

Zinc is an essential trace element that plays a crucial role in catalytic, structural and regulatory functions of many proteins including enzymes and transcription factors; thus maintenance of zinc balance is critical for normal cellular function. Cellular mechanisms that maintain zinc balance include the regulation of genes coding for proteins that play vital roles in zinc homeostasis. These proteins include zinc transporters belonging to the ZIP (SLC39A) and ZnT (SLC30A) families as well as the zinc-binding metallothionein proteins. In contrast to bacterial and yeast systems, a transcription factor responsible for mediating transcriptional repression of a suite of genes in response to elevated zinc levels in mammals has hitherto not been identified. Using Caco-2 cells as a model of human intestinal epithelial cells and detection of protein binding by electrophoretic mobility shift analysis, we show that zinc finger protein ZNF658 binds specifically to the zinc transcriptional regulatory element (ZTRE), previously demonstrated to mediate this response in a panel of three genes: SLC30A5 (ZnT5 zinc transporter), SLC30A10 (ZnT10 zinc transporter) and CBWD (whose prokaryotic homologs are emerging players in metal biology). We also demonstrate that siRNA-driven reduction of ZNF658 attenuated or abrogated transcriptional repression in response to elevated zinc levels of these same genes by measuring transcript abundance using RT-qPCR and using promoter-reporter gene constructs. In addition, the region of ZNF658 responsible for binding to the ZTRE was identified (the C-terminal zinc finger domain) and the requirement for both sides of the palindromic ZTRE sequence for function was demonstrated. This study therefore identifies the first metazoan transcription factor that plays a pivotal role in the orchestrated cellular response to increased zinc levels to restore cellular zinc balance necessary to achieve a broad spectrum of zinc-dependent functions and begins to probe its molecular action. We also report an important role for the mammalian CBWD gene product in protection of cells from either depleted or excess zinc by virtue of the fact that overexpression of recombinant CBWD protein altered cellular tolerance to both elevated and depleted levels of zinc consistent with a homeostatic function. In addition, we present preliminary evidence that changes in the expression of ZNF658 and its target genes, in particular SLC30A10 (ZnT10), may be related to cell senescence, suggesting that changes in zinc homeostasis are components of this process. Overall, the work presented contributes to understanding zinc regulated gene expression and cellular zinc homeostasis.

Though development of the cerebral cortex is of singular importance to human cognition, it remains very poorly understood. Microcephaly, or "small head," is a neurodevelopmental disorder causing significantly reduced cerebral cortex size, and the disease has proved to be a useful model system for elucidating the steps essential for proper cortical development and cognitive function. Many known microcephaly gene products localize to centrosomes, regulating cell fate and proliferation, however, the elucidation of different microcephaly genes with different functions may shed light on previously unidentified key steps of brain development. We identify and characterize a nuclear zinc finger protein, ZNF335/NIF-1, as a causative gene for severe microcephaly, small somatic size, and neonatal death. Znf335-null mice are embryonically lethal and conditional knockout leads to severely reduced cortical size. RNA-interference and postmortem human studies show that Znf335 is essential for neural progenitor self-renewal, neurogenesis, and neuronal differentiation. ZNF335 is a component of a vertebrate-specific, trithorax H3K4-methylation complex, directly regulating REST/NRSF, a master regulator of neural gene expression and cell fate, as well as other essential neural-specific genes. Our results reveal ZNF335 as an essential link between H3K4 complexes and REST/NRSF, and provide the first direct genetic evidence that this pathway regulates human neurogenesis and neuronal differentiation.

ZNF217, un nouveau membre de la famille krüppel-like, est un facteur de transcription qui interagit avec des co-répresseurs et des protéines modifiant les histones suggérant que ZNF217 ferait partie d'un complexe répresseur de la transcription. ZNF217 serait un oncogène mais ses fonctions sont encore mal connues à l'heure actuelle. Les objectifs de ce travail ont été d'étudier le rôle de ZNF217 dans l'échappement tumoral et sa valeur pronostique dans le cancer du sein. Ainsi, nous avons montré que de forts niveaux d'expression de ZNF217 sont associés à : (i) une augmentation de la prolifération cellulaire in vitro et de la croissance tumorale in vivo, (ii) la stimulation de l'invasion et de la migration cellulaire, (iii) l'induction de l'EMT via la voie du TGF-β. De plus, les cellules surexprimant ZNF217 sont résistantes au paclitaxel et cette résistance est associée à la dérégulation de l'expression des membres de la famille Bcl-2 et d'Aurora-A. Enfin, nous avons montré pour la première fois que des forts niveaux d'expression d'ARNm de ZNF217 représentent un nouveau marqueur de mauvais pronostic dans le cancer du sein et sont associés au développement de métastases. ZNF217 semble donc jouer un rôle important dans la cancérogénèse mammaire et des stratégies thérapeutiques ciblant directement ZNF217 ou ciblant ses médiateurs (Aurora-A ou TGF-β) pourraient être utilisées en clinique dans le traitement des tumeurs mammaires surexprimant ZNF217

ZNF217, un nouveau membre de la famille krüppel-like, est un facteur de transcription qui interagit avec des co-répresseurs et des protéines modifiant les histones suggérant que ZNF217 ferait partie d’un complexe répresseur de la transcription. ZNF217 serait un oncogène mais ses fonctions sont encore mal connues à l’heure actuelle. Les objectifs de ce travail ont été d’étudier le rôle de ZNF217 dans l’échappement tumoral et sa valeur pronostique dans le cancer du sein. Ainsi, nous avons montré que de forts niveaux d’expression de ZNF217 sont associés à : (i) une augmentation de la prolifération cellulaire in vitro et de la croissance tumorale in vivo, (ii) la stimulation de l’invasion et de la migration cellulaire, (iii) l’induction de l’EMT via la voie du TGF-β. De plus, les cellules surexprimant ZNF217 sont résistantes au paclitaxel et cette résistance est associée à la dérégulation de l’expression des membres de la famille Bcl-2 et d’Aurora-A. Enfin, nous avons montré pour la première fois que des forts niveaux d’expression d’ARNm de ZNF217 représentent un nouveau marqueur de mauvais pronostic dans le cancer du sein et sont associés au développement de métastases. ZNF217 semble donc jouer un rôle important dans la cancérogénèse mammaire et des stratégies thérapeutiques ciblant directement ZNF217 ou ciblant ses médiateurs (Aurora-A ou TGF-β) pourraient être utilisées en clinique dans le traitement des tumeurs mammaires surexprimant ZNF217
ZNF217, a new member of the Krüppel-like family, is a transcription factor which interacts with co-repressors and histone-modifying proteins suggesting that ZNF217 may be part of a transcriptional repressor complex. ZNF217 may be an oncogene but little is known about the functions that ZNF217 could play. The aim of this work is to study the role of ZNF217 in tumor escape and its prognostic value in breast cancer. We showed that ZNF217 is associated with (i) increased proliferation in vitro and tumoral growth in vivo, (ii) stimulation of cell invasion and migration (iii) induction of EMT via the TGF-β pathway. Moreover, ZNF217-overexpressed cells are resistant to paclitaxel and ZNF217-induced resistance is associated with deregulated expression of the Bcl-2 family members and Aurora-A. Finally, we showed for the first time that high ZNF217 mRNA level is a novel marker of poor prognosis in breast cancer and is associated with the developpement of metastasis. Thus, ZNF217 seems to be important in mammary cancerogenesis. Clinical strategies targeting either ZNF217 directly or targeting ZNF217 mediators (eg Aurora-A or TGF-β) could be used for the treatment of breast cancer with ZNF217 overexpression

碩士
逢甲大學
國際貿易所
100
Over the past few years, e-services have become increasingly popular in mainstream society. To this end, most online business entrepreneurs seek out attractive marketing strategies to gain customer loyalty. Currently because of online marketing techniques, the internet has become a perfectly competitive market. Increased competition from internet business gives consumers increased choices and better service possibilities. When customers have many choices, combined with the convenience of internet buying, selling products becomes easier for those who want to operate e-services. Therefore, businesses strive to win customers’ loyalty. The purpose of this study is to examine the effects of perceived service quality, technology, fashion, and customer satisfaction on the customer’s loyalty for e-service in Taiwan. The data were collected by questionnaires given to Taiwanese people. Structural Equation Model (SEM) was used to analyze the data and reliability analysis was performed too to test the reliability of the study. The findings of this study show that independent variables affect customer’s loyalty for e-service in Taiwan.

碩士
國立中山大學
資訊工程學系研究所
106
This study uses deep neural networks to construct the static and dynamic speech emotion recognition systems and integrates the static and dynamic models by ensemble learning. The static model is based on multi-layer perceptron (MLP) and convolutional neural network (CNN). The dynamic model is based on recurrent neural network (RNN). Our CNN recognizer learns to focus on salient parts of signal by the attention mechanism, and promotes competition among a set of multi-scale convolutional filters by multi-scale convolution module. The RNN recognizer also incorporates the attention mechanism to learn to focus on the informative segments. We adopt a skew-robust training criterion to deal with unbalanced data. We also exploit a two-pass teacher-student training scheme to deal with the issue of noisy labels. The proposed speech emotion recognition systems are evaluated on the FAU-Aibo corpus, using the tasks as defined in the Interspeech 2009 Emotion Challenge classifier sub-challenge, with the performance measure of unweighted average recall rate (UA). Our MLP and CNN models achieve 46.2% and 46.4% UA respectively, and our dynamic model with deep RNN achieves 47.2% UA, surpassing the previous best mark of 46.4%. Further, an ensemble learning implemented by interpolation that combines the static and dynamic models achieves 50.5% UA, breaking the 50.0% barrier on the FAU-Aibo tasks for the first time since the Challenge is posted.