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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.
11

Discovery of cancer splicing and associated auto-regulatory networks through cross-species circadian analysis

Ramasamy Subramanian, Krithika January 2019 (has links)
No description available.
12

The CCAAT-box binding transcription factor, nuclear factor-Y (NF-Y) regulates transcription of human aldo-keto reductase 1C1 (AKR1C1) gene

Pallai, Rajash January 2010 (has links)
Dihydrodiol dehydrogenases are a family of aldo-keto reductases (AKR1Cs) involved in the metabolism of steroid hormones and xenobiotics. Whilst, several phase II drugs as well as endogenous & exogenous steroids/steroid metabolites have been identified as inducers of gene transcription, the cellular transcription factors controlling the expression of AKR1C1 are incompletely elucidated. Herein, we have cloned and characterized the proximal promoter region of the human AKR1C1 gene that controls its transcription. The 5’ flanking proximal promoter region of the AKR1C1 gene consists of a TATA box and an inverted CCAAT binding site. Deletion analysis of the 5’-flanking, ~3.0 kb region of the human AKR1C1 gene identified the region between -128 to -88 as the minimal proximal promoter essential for basal transcription of AKR1C1 in human ovarian (2008 & 2008/C13*), lung (H23 & A549) and liver carcinoma (HepG2) cells. Antioxidant response elements (ARE) have been shown to modulate the transcription ofv genes coding for phase II drug metabolizing enzymes. Cloning of the ARE upstream of the AKR1C1 proximal promoter resulted in increased transcription in human lung adenocarcinoma and liver hepatoblastoma cells but not in human ovarian carcinoma cells. Further, ARE increased the induction of the AKR1C1 gene in response to treatment with phase II drug inducers. However, ARE did not induce the transcription of AKR1C1 gene promoter in the presence of cisplatin in any of the cell lines. A computational analysis utilizing the Alibaba 2.0 on the proximal AKR1C1 gene promoter region was performed to identify potential transcription factor binding sites. Based on this analysis, a set of potential, putative transcription factor binding sites for Oct1, Sp1, Cp-1/NF-Y, CEBP, p40X, USF, NF1 and AP-2 were identified in the region -180 to -88 of the AKR1C1 gene promoter. Site-directed mutagenesis studies indicated that the transcription factor binding sites for NF-Y/CEBP were involved in controlling the basal transcription of AKR1C1 in all the cancer cells studied. Electrophoretic mobility shift (EMSAs) and gel supershift assays demonstrated that the transcription factor NF-Y preferentially binds to the inverted CCAAT box at -109ATTGG-105 of the AKR1C1 gene. Chromatin immunoprecipitation (ChIP) analysis confirmed the in vivo association between NF-Y and human AKR1C1 gene promoter in human ovarian, lung and liver carcinoma cells. Further, ectopic expression of NF-Y’s increased the AKR1C1 gene transcription, whereas expression of a dominant-negative NF-YA or knockdown of NF-YA by siRNA transfection, decreased the AKR1C1 gene transcription. A 2-fold increase in AKR1C1 transcription was observed specifically in cisplatin-treated 2008 cells that was CCAAT box-dependent. These results indicate that NF-Y regulates basal transcription of AKR1C1 in human ovarian, lung and liver carcinoma cells and cisplatin-induced transcription in human ovarian carcinoma cells. / Pathology
13

TRPA1- FGFR2 binding event is a regulatory oncogenic driver modulated by miRNA-142-3p

Berrout, J., Kyriakopoulou, E., Moparthi, L., Hogea, A.S., Berrout, L., Ivan, C., Lorger, M., Boyle, J., Peers, C., Muench, S., Elies, Jacobo, Hu, X., Hurst, C., Hall, T., Umamaheswaran, S., Wesley, L., Gagea, M., Shires, M., Manfield, I., Knowles, M.A., Davies, S., Suhling, K., Gonzalez, Y.T., Carragher, N., Macleod, K., Abbott, N.J., Calin, G.A., Gamper, N., Zygmunt, P.M., Timsah, Z. 2017 October 1916 (has links)
Yes / Recent evidence suggests that the ion channel TRPA1 is implicated in lung adenocarcinoma (LUAD) where its role and mechanism of action remain unknown. We have previously established that the membrane receptor FGFR2 drives LUAD progression through aberrant protein-protein interactions mediated via its C-terminal proline rich motif. Here, we report that the N-terminal ankyrin repeats of TRPA1 directly bind to the C-terminal proline rich motif of FGFR2 inducing the constitutive activation of the receptor, thereby prompting LUAD progression and metastasis. Furthermore, we show that upon metastasis to the brain, TRPA1 gets depleted, an effect triggered by the transfer of TRPA1-targeting exosomal microRNA (miRNA-142-3p) from brain astrocytes to cancer cells. This downregulation, in turn, inhibits TRPA1-mediated activation of FGFR2 hindering the metastatic process. Our study reveals a direct binding event and characterizes the role of TRPA1 ankyrin repeats in regulating FGFR2-driven oncogenic process; a mechanism that is hindered by miRNA-142-3p. / Faculty of Biological Sciences at the University of Leeds, Wellcome Trust Seed Award, Royal Society Research Grant RG150100, MR/K021303/1, Swedish Research Council (2014-3801) and the Medical Faculty at Lund University.
14

THE MECHANOTRANSDUCTION OF PRIMARY CILIA IN TUMOR PROGRESSION OF LUNG ADENOCARCINOMA

Patel, Sagar 25 April 2013 (has links)
The objective of this study was to investigate primary cilia and their mechanotransduction role in lung adenocarcinoma tumor progression. The main focus investigated the effect of primary cilia on cell cycle progression, survival, adhesion and migration analysis of these cells and the role of sonic hedgehog signaling pathway in mechanotransduction. Human Non-Small Cell Lung Cancer (NSCLC) adenocarcinoma biopsies contain more primary cilia than non-tumor lung sections. To observe the effects of primary cilia presence in lung cancer cells in-vitro, formation of primary cilia is inhibited using small interfering RNA. A549 cells with intact primary cilia observe less cell cycle progression than cells deficient in primary cilia under static and cyclic stretch conditions. Primary cilia cause higher cell survival and adhesion. Increase in cell adhesion also increases the migration and wound closure rates in control samples compared to samples treated with inhibition of IFT88, thereby increasing the metastasis of these cells. Several downstream regulatory genes in sonic hedgehog signaling pathway observe significantly decreased gene expressions in primary cilia deficient cells, thus indicating inefficient mechanotransduction. Therefore, cancer cells need primary cilia to survive, adhere and migrate and continue tumor progression.
15

PRIMARY CILIA MECHANOTRANSDUCTION AND MICROTUBULE STABILITY IN MECHANICALLY STRETCHED LUNG ADENOCARCINOMA CELLS

Radhika, Monika Rassi 01 January 2015 (has links)
The objective of this study is to investigate the role of microtubule based organelle, the primary cilia in lung adenocarcinoma by i) Quantifying the presence of primary cilia in several Non Small Cell Lung Cancer (NSCLC) cell lines in response to mechanical stimuli, ii) Attempting to determine the role of primary cilia in cell migration, iii) Investigating the effects of Paclitaxel(Taxol) resistance in lung cancer cells, iv) Analyzing the response of lung cancer cells to Smoothened Inhibitors and v) Determining the effects of Transforming Growth Factor Beta-1(TGF-β1) induced Epithelial to Mesenchymal Transition(EMT) in lung cancer cells. To ascertain the effects of primary cilia in the hall marks of tumor progression, several experiments involved prohibition of primary cilia formation by silencing IFT88, the gene responsible using small interfering RNA. Three out of the five cell lines tested, showed increased expression of primary cilia under mechanical stretch. IFT88 inhibition of H460 cells decreased their migration rate to the injury site under stretch conditions. Smoothened (SMO) Inhibitors decreased proliferation and migration rates in human lung adenocarcinoma cell lines (A549luc) similar to the effects observed in IFT88 silenced cells. IFT88 silenced A549luc cells showed a partial reversal of TGF-beta1 induced up-regulation of a mesenchymal marker. These results indicate that primary cilia play a role in the progression and metastasis of lung cancer by aiding the adhesion, proliferation, migration and EMT of lung cancer cells.
16

Strategies towards the synthesis of 4-(3-methyl-but-1-enyl)-3,5,3',4'-tetrahydroxystilbene (arachidin-1) and resveratrol analogues

Olusegun-Osoba, Elizabeth Oluwakemi January 2015 (has links)
Stilbene phytoalexins such as resveratrol, 1, and the arachidins, including arachidin-1,2, are naturally synthesised by peanut (Arachis hypogaea) plants. The peanut phytoalexins are polyphenolic compounds consisting of a stilbene backbone, with a number of derivatives also possessing a prenyl moiety. These distinctive phytoalexins have gained attention, as they exhibit various biological activities, for instance arachidin-1, 2, has been reported to be more potent than resveratrol, 1, in the inhibition of lipopolysaccharide-induced expression of cyclooxygenase-2 (COX-2) and COX-2 mRNA, in vitro at doses that were low in cytotoxicity. Additionally the various arachidins have recently been shown to exhibit their anti-inflammatory properties, through the inhibition of a number of inflammatory mediator pathways. In this work, various routes into the synthesis of arachidin-1, 2, are described, via use of the Horner-Wadsworth-Emmons (HWE) reaction. Three different methodologies were explored, the first approach involving silyl ether (TIPS or TBDMS) protected benzaldehydes, proved unsuccessful due to cleavage of the silyl ether protecting groups, in basic and/or acidic conditions. This led to an alternative approach, whereby formation of the stilbene backbone proceeded via the regioselective demethylation of an acetal in the presence of sodium metal, subsequent electrophilic substitution using iodomethane and finally acetal hydrolysis of the acetal, gave the isolated aldehyde in moderate yield (52 %). Coupling of the aldehyde with the substituted benzylphosphonate, via the HWE reaction gave the desired trans-stilbene in good yield (86 %), however incorporation of the prenyl side chain proved to be challenging via the Wohl-Ziegler bromination. Further adaptation of the aforementioned route, whereby alkylation using diethyl iodomethylphosphonate, enabled the incorporation of the prenyl moiety and the subsequent construction of the trans-stilbene backbone, gave the 4-(3-methyl-but-1- enyl)-3,5,3',4'-tetramethoxystilbene, 3, albeit in poor yield (47 %). The final step involving demethylation using BBr3 gave arachidin-1, 2, also in poor yield (30 %), nevertheless this approach has been proved to be a successful route for the total synthesis of arachidin-1, 2, however optimised studies are required in order to obtain the desired compound in quantitative yields. Synthetic analogues of resveratrol, 1, are also known for their biological activities, including anti-inflammatory and chemopreventative properties. Recently, the anti-proliferative activity of a number of stilbenesulfonamides, against the National Cancer Institute's 60 (NCI-60) human tumour cell line has been reported. Furthermore, the anti-inflammatory effects of novel heterocyclic methylsulfone and sulfonamide analogues, via inhibition of the COX-2 protein have also been published, however both synthetic routes described require a total of six or seven steps, from the sulfanilamide and are limited to the synthesis of primary sulphonamides (SO2NH2). In this work, an efficient three step synthesis has been designed and successfully implemented, proceeding via chlorosulfonation of diethyl benzylphosphonate, to form the sulfonyl chloride intermediate. Aminolysis of the sulfonyl chloride intermediate was then performed, using a range of primary, secondary and cyclic alkyl amines, as well as aromatic amines; including ammonia, dimethylamine, morpholine and diphenylamine. Finally, formation of the stilbene backbone with various substituted aldehydes, via the HWE reaction offered a short, versatile and alternative route to the synthesis of novel primary, secondary and tertiary trans-stilbene benzenesulfonamides and heterocyclic analogues, in yields of 42 - 100 %. The activity of a selection of the synthesised stilbene benzenesulfonamides was evaluated against the human lung adenocarcinoma epithelial cell line (A549). Amongst the compounds tested, analysis of the data showed that the novel analogue, 4, was found to be the most potent compound, with a GI50 of 0.1 μM. Comparison with the previously published data found analogue, 4, to be approximately 500-fold more potent than the lead compound resveratrol, 1, (GI50 = 51.64 μM) and approximately twice as potent than 5-fluorouracil (GI50 = 0.189μM), a chemotherapy drug used to treat various forms of cancer 8. Overall, these results demonstrate that the total synthesis of trans-arachidin-1, 2, can be achieved via a five step methodology. A versatile route to the synthesis of novel stilbene benzenesulfonamides has also been successfully achieved, amongst the compounds synthesised one appears to show promising anticancer activity, and warrants further investigation (i.e. in vitro studies using other cancer cell lines, and the synthesis of additional compounds using analogue, 4, as a lead compound).
17

Regulation of ERK3 by KRAS signalling and its role in the growth of lung adenocarcinoma (LUAD) cells

Akunapuram, Shreya 09 August 2023 (has links)
No description available.
18

LKB1 Loss in Lung Adenocarcinoma

Koenig, Michael J. 28 August 2019 (has links)
No description available.
19

DIRECT PP2A ACTIVATION FOR THE TREATMENT OF KRAS- AND EGFR-DRIVEN LUNG ADENOCARCINOMA

Tohme, Rita 04 June 2018 (has links)
No description available.
20

Funciones del factor de inicio de la traducción eucariota 5A2 en el cáncer de pulmón

Martínez Férriz, Arantxa 12 May 2023 (has links)
[ES] Las poliaminas son metabolitos esenciales para el crecimiento de las células eucariotas y su metabolismo está frecuentemente desregulado en cáncer. Una de las dianas moleculares de las poliaminas es el factor de elongación de la traducción eIF5A, una proteína esencial y conservada evolutivamente. eIF5A es la única proteína conocida que contiene el aminoácido hipusina, que deriva de la poliamina espermidina. En humanos existen dos isoformas, eIF5A1 y eIF5A2. EIF5A2 se encuentra en el cromosoma 3q26, una región frecuentemente amplificada en muchos tumores y que está altamente expresada en varios tipos de cáncer, incluyendo el cáncer de pulmón no microcítico (CPNM). eIF5A2 es esencial para el mantenimiento de la proliferación celular y su inhibición la suprime en algunos tumores. Recientemente se ha correlacionado la sobreexpresión de eIF5A2 con la invasión y como biomarcador de mal pronóstico en algunos cánceres, y se ha observado que eIF5A2 induce la transición epitelio-mesenquimal (EMT) en CPNM. La EMT es un proceso complejo y reversible que induce la diferenciación de las células epiteliales a células mesenquimales migrantes con capacidad de invasión. Numerosos estudios han demostrado que la EMT está relacionada con la progresión del cáncer, metástasis y mal pronóstico en tumores. Por tanto, la determinación de un método eficaz para inhibir la EMT en CPNM podría mejorar significativamente los tratamientos actuales. La naturaleza altamente selectiva de la hipusinación de eIF5A2 y su susceptibilidad a la inhibición farmacológica sugieren que eIF5A2 es una diana terapéutica muy atractiva. Actualmente, se dispone de un análogo de poliamina, GC7, que se utiliza para inhibir la hipusinación y se ha demostrado que frena el crecimiento de células cancerosas. El presente trabajo de tesis doctoral tiene como objetivo caracterizar el papel patológico de eIF5A2 en el desarrollo del CPNM. Para ello, hemos estudiado, mediante modificaciones genéticas por silenciamiento y sobreexpresión, el papel de eIF5A2 en la proliferación, motilidad e invasión celular utilizando líneas celulares de CPNM. Así mismo, se ha estudiado el efecto del inhibidor GC7 en líneas celulares de CPNM y modelos murinos para determinar si previene o revierte la EMT, y reduce la migración y la invasión de células de CPNM. Por último, se ha analizado la correlación entre la expresión de eIF5A2, las variables clínico-patológicas y la supervivencia de los pacientes en una colección de muestras de pacientes con CPNM. Los resultados obtenidos sugieren la existencia de una regulación entre las isoformas eIF5A1 y eIF5A2 para compensar la expresión de ambos homólogos. Además, nuestros datos apuntan a una coordinación temporal y posicional entre las vías de TGFß1 y eIF5A2 para impulsar la traducción de proteínas requerida para el reordenamiento del citoesqueleto y la motilidad de las células cancerosas invasivas. Hemos demostrado con modelos de ratón in vivo, que los tumores generados mediante xenotrasplante de células que sobreexpresan eIF5A2 tienen mayor capacidad invasiva. Finalmente, mostramos la existencia de una correlación positiva entre la expresión de eIF5A2 y el marcador de proliferación Ki67 en tejido de tumores de CPNM, y que la tasa de supervivencia es menor en aquellos pacientes que expresan niveles elevados de eIF5A2. Los resultados obtenidos en este trabajo confirman que eIF5A2 podría ser empleado como un biomarcador de mal pronóstico en CPNM y su inhibición farmacológica podría emplearse como una posible herramienta terapéutica, sola o en combinación con otros fármacos, en aquellos casos en los que eIF5A2 se encuentre sobreexpresado. / [CA] Les poliamines són metabòlits essencials per al creixement de les cèl·lules eucariotes i el seu metabolisme està frequentment desregulat en càncer. Una de les dianes moleculars de les poliamines és el factor d'elongació de la traducció eIF5A, una proteïna essencial i conservada evolutivament. eIF5A és l'única proteïna cel·lular coneguda que conté l'aminoàcid hipusina, que deriva de la poliamina espermidina. En humans hi ha dues isoformes, eIF5A1 i eIF5A2. EIF5A2 es troba al cromosoma 3q26, una regió freqüentment amplificada en molts tumors, i que està altament expressada en diferent tipus de càncer, incloent el càncer de pulmó no microcític (CPNM). eIF5A2 és essencial per al manteniment de la proliferació cel·lular i la seva inhibició la suprimeix en alguns tumors. Recentment s'ha correlacionat la sobreexpressió d'eIF5A2 amb la invasió i com a biomarcador de mal pronòstic a alguns càncers i s'ha observat que eIF5A2 indueix la transicició epiteli-mesenquima (EMT) en CPNM. L'EMT és un procés complex i reversible que indueix la diferenciació de les cèl·lules epitelials a cèl·lules mesenquimals migrants amb capacitat d'invasió. Nombrosos estudis han demostrat que l'EMT està relacionada amb la progressió del càncer, la metàstasi i el mal pronòstic en molts tumors. Per tant, la determinació d'un mètode eficaç per inhibir l'EMT a CPNM podria millorar significativament els règims dels tractaments actuals. La naturalesa altament selectiva de la hipusinació d'eIF5A2 i la susceptibilitat a la inhibició farmacològica fan d'aquesta proteina una diana terapèutica molt atractiva. Actualment, es disposa d'un anàleg de poliamina, anomenat GC7, que s'utilitza per inactivar la reacció d'hipusinació i s'ha demostrat que inhibeix el creixement de cèl·lules canceroses. Aquest treball de tesi doctoral té com a objectiu caracteritzar el paper patològic d'eIF5A2 en el desenvolupament del CPNM. Per això, hem estudiat, mitjançant modificacions genètiques per silenciament i sobreexpressió, el paper d'eIF5A2 en la proliferació, la motilitat i la invasió cel·lular utilitzant línies cel·lulars de càncer de pulmó. Així mateix, s'ha estudiat l'efecte de l'inhibidor GC7 en línies cel·lulars de CPNM i models murins per determinar si augmenta la quimiosensibilitat de les cèl·lules, prevé o reverteix l'EMT i redueix la migració i la invasió de cèl·lules de CPNM. Finalment, s'ha analitzat la correlació entre l'expressió d'eIF5A2, les variables clinicopatològiques i la supervivència dels pacients en una col·lecció de mostres de pacients amb CPNM. Els resultats obtinguts suggereixen que hi ha una regulació entre les isoformes eIF5A1 i eIF5A2 per compensar l'expressió dels dos homòlegs. A més, les nostres dades apunten a una coordinació temporal i posicional entre les vies de TGFß1 i eIF5A2 per impulsar la traducció requerida de proteïnes per als reordenaments del citosquelet i les característiques de motilitat de les cèl·lules canceroses invasives. Hem demostrat amb models de ratolí in vivo que els tumors generats mitjançant xenotrasplantament de cèl·lules que sobreexpressen eIF5A2 tenen més capacitat invasiva. Finalment, mostrem l'existència una correlació positiva entre l'expressió d'eIF5A2 i el marcador de proliferació Ki67 en teixit de tumors de CPNM, i que la taxa de supervivència és menor en aquells pacients que expressaven alts nivells d'eIF5A2. Els resultats obtinguts en aquest treball confirmen que eIF5A2 podria ser emprat com un biomarcador de mal pronòstic a CPNM i la seva inhibició farmacològica podria utilitzar-se com una possible eina terapèutica, sola o en combinació amb altres fàrmacs, en aquells casos en què eIF5A2 es trobe sobreexpressat. / [EN] Polyamines are essential metabolites for eukaryotic cells growth, and their metabolism is frequently deregulated in cancer. One of the molecular targets of polyamines is the translation elongation factor eIF5A, an essential and evolutionarily conserved protein. eIF5A is the only protein known that contains the amino acid hypusine, which is derived from the polyamine spermidine. In humans there are two isoforms, eIF5A1 and eIF5A2. EIF5A2 is located on chromosome 3q26, a region frequently amplified in different types of cancer, including non-small cell lung cancer (NSCLC). eIF5A2 is essential for the maintenance of cell proliferation and its inhibition suppresses it in many tumors. Recently, eIF5A2 overexpression has been correlated with invasion and as a biomarker of poor prognosis in some cancers, and it has been observed that eIF5A2 induces epithelial-mesenchymal transition (EMT) in NSCLC. EMT is a complex and reversible process that induces the differentiation of epithelial cells into migrant mesenchymal cells with invasive capacity. Numerous studies have shown that EMT is related to cancer progression, metastasis, and poor prognosis in many tumors. Therefore, the determination of an effective method to inhibit EMT in NSCLC could significantly improve current treatment regimens. The highly selective nature of eIF5A2 hypusination and its susceptibility to pharmacological inhibition make this process a very attractive therapeutic target. Currently, a polyamine analog, called GC7, is available and is used to inactivate the hypusination reaction and has been shown to inhibit cancer cell growth. The objective of this doctoral thesis is to characterize the pathological role of eIF5A2 in the development of NSCLC. For this, we have studied, through genetic alterations by silencing and overexpression, the role of eIF5A2 in cell proliferation, motility and invasion using lung cancer cell lines. Likewise, the effect of the GC7 inhibitor in NSCLC cell lines and murine models has been studied to determine if it increases the chemosensitivity of cells, prevents or reverses EMT, and reduces migration and invasion of NSCLC cells. Finally, the correlation between the expression of eIF5A2, clinicopathological variables and patient survival has been analyzed in a collection of samples from patients with NSCLC. The results obtained suggest the existence of a regulation between the eIF5A1 and eIF5A2 isoforms to compensate the expression of both homologues. Furthermore, our data point to a temporal and positional coordination between the TGFß1 and eIF5A2 pathways to drive the required translation of proteins for cytoskeletal rearrangements and motility characteristics of invasive cancer cells. We have demonstrated with in vivo mouse models that tumors generated by xenotransplantation of cells that overexpress eIF5A2 have a greater invasive capacity. Finally, we show the existence of a positive correlation between the expression of eIF5A2 and the proliferation marker Ki67 in NSCLC tumor tissue, and that the survival rate is lower in those patients who expressed high levels of eIF5A2. The results obtained in this work confirm that eIF5A2 could be used as a biomarker of poor prognosis in NSCLC and its pharmacological inhibition could be used as a possible therapeutic tool, alone or in combination with other drugs, in those cases in which eIF5A2 is found overexpressed. / Martínez Férriz, A. (2023). Funciones del factor de inicio de la traducción eucariota 5A2 en el cáncer de pulmón [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/193293

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