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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.
71

Does degradation of human vault RNA3 by RNA interference reduce multidrug resistance in GLC4/REV, a small-cell lung cancer cell line?

Adam, Michael R. January 2004 (has links)
Vaults, recently discovered in 1986, are multi-subunit organelles with a molecular mass of ,--,13 MDa. The specific function of vaults is unknown, although they are believed to be involved in internal transport. These ribonucleoproteins are composed of the major vault protein, which comprises ' 70% of the vault's mass, two minor proteins, TEP1 and vPARP, and untranslated RNA(s). It is believed that the protein components of the vault are structural while the RNAs are the functional components. Implications of the vault's involvement in multi-drug resistance in cancer have been made. In some resistant cancer cells, the major vault protein and vRNA(s) are up-regulated up to 15 times when cells are exposed to a cytotoxic drug. Cytotoxic drugs such as doxorubicin are administered as a cancer treatment, but may be ineffective because the drug is actively pumped out of the cell. Multi-drug resistance is the most common failure of chemotherapeutic cancer treatment. In order to prevent the development of multi-drug resistance this research employed the use of small interfering RNA technology to down-regulate the expression of one of the vault RNAs, vRNA3, in cultured GLC4 cells, a small-cell lung cancer cell line. If the vRNA(s) are the functional portion of the vault and a cloned siRNA prevents their up-regulation after drug exposure, the cells should lose their multi-drug resistance, stimulating apoptosis. If successful, this approach may provide an alternative approach to cancer treatment in cells which respond to chemotherapy by increasing the number of vault particles.Initially, the transfection of a plasmid into GLC4 cells was optimized. The best transfection efficiency (N20%) was obtained by using GeneTherapySystems' GenePORTER2 transfection reagent in serum free conditions. To determine if the vault RNAs are the functional portion of the vault complex that confers multi-drug resistance to a cell, a small interfering RNA fragment was designed to specifically knock-down the expression of human vault RNA 3. The siRNA sequence homologous to a portion of vault RNA3 was cloned into an expression vector, and using optimized transfection protocols was transfected into GLC4/REV cells. A Western analysis using caspase-8 antibodies showed no difference in caspase-8 expression in doxorubicin treated and untreated cells. Preliminary results yielded by reverse transcriptase polymerase chain reaction amplification of isolated RNA indicated that the vRNAs were not down-regulated by the siRNAs. / Department of Biology
72

Dissociating the Disease from the Diseased

January 2013 (has links)
abstract: Lung Cancer Alliance, a nonprofit organization, released the "No One Deserves to Die" advertising campaign in June 2012. The campaign visuals presented a clean, simple message to the public: the stigma associated with lung cancer drives marginalization of lung cancer patients. Lung Cancer Alliance (LCA) asserts that negative public attitude toward lung cancer stems from unacknowledged moral judgments that generate 'stigma.' The campaign materials are meant to expose and challenge these common public category-making processes that occur when subconsciously evaluating lung cancer patients. These processes involve comparison, perception of difference, and exclusion. The campaign implies that society sees suffering of lung cancer patients as indicative of moral failure, thus, not warranting assistance from society, which leads to marginalization of the diseased. Attributing to society a morally laden view of the disease, the campaign extends this view to its logical end and makes it explicit: lung cancer patients no longer deserve to live because they themselves caused the disease (by smoking). This judgment and resulting marginalization is, according to LCA, evident in the ways lung cancer patients are marginalized relative to other diseases via minimal research funding, high- mortality rates and low awareness of the disease. Therefore, society commits an injustice against those with lung cancer. This research analyzes the relationship between disease, identity-making, and responsibilities within society as represented by this stigma framework. LCA asserts that society understands lung cancer in terms of stigma, and advocates that society's understanding of lung cancer should be shifted from a stigma framework toward a medical framework. Analysis of identity-making and responsibility encoded in both frameworks contributes to evaluation of the significance of reframing this disease. One aim of this thesis is to explore the relationship between these frameworks in medical sociology. The results show a complex interaction that suggest trading one frame for another will not destigmatize the lung cancer patient. Those interactions cause tangible harms, such as high mortality rates, and there are important implications for other communities that experience a stigmatized disease. / Dissertation/Thesis / M.S. Biology 2013
73

Determining the anti-cancer properties of zinc and novel quinoxaline derivatives on lung cancer cells

Sibiya, Mixo Aunny January 2020 (has links)
Thesis (M.Sc. (Biochemistry)) -- University of Limpopo, 2020 / Despite major advancements in the development of various chemotherapuetic agents, treatment for lung cancer remains costly, ineffective, toxic to neighbouring normal noncancerous cells and still hampered by high level of remissions (Wistuba et al., 2018; Tana et al., 2016; Schiller et al., 2002). Synthesis of novel quinoxalines with a wide spectrum of biological activities has recently received considerable attention with promising anticancer drug activity since most of them do not affect non-cancerous cells and are derived from readily available less costly raw materials (Srivastava et al., 2014). Since combination treatment has been shown to augment and improve single drug treatment, trace elements were employed in this study in combination with quinoxalines derivatives (Gomez et al., 2016; Kocdor et al., 2015; Ku et al., 2012; John et al., 2010; Killile and Killilea, 2007). Zinc is an essential element that is integral to many proteins and transcription factors which regulate key cellular functions such as the response to oxidative stress, DNA replication, DNA damage repair, cell cycle progression, and apoptosis (Dhawan and Chadha, 2010). Owing to the importance of these two approaches, the aim of this study was to provide in vitro preliminary anticancer activity data on A549 lung cancer cells using combination of zinc and quinoxaline derivatives. An assessment of the quinoxaline derivatives ferric reducing power and DPPH free radical scavenging activity was performed. The cytotoxic and anti-proliferation activity of these derivatives and zinc on cancer cell lines was determined using the MTT assay. The ability of the quinoxaline derivatives and zinc to modulate oxidative stress was evaluated using the H2DCFDA fluorescence assay. Cell cycle arrest stages were analysed by flow cytometry through propidium iodide cell cycle analyses. The ability of the quinoxaline derivatives to induce apoptosis in cancer cells was assessed using DAPI/PI, Acridine Orange/Ethidium Bromide (AO/EB) and Annexin V-FITC/Dead Cell assays. Western blot was used to investigate the Bcl/Bax expression ratios in A549 lung cancer cells after treatment with quinoxaline derivatives, zinc and in combination. Of the four quinoxaline derivatives tested, 3-(quinoxaline-3-yl) prop-2-ynyl methanosulphate (LA-39B) and 3-(quinoxaline-3-yl) prop-2-yn-1-ol (LA-55) produced significant anticancer properties against A549 lung cancer cells at minimal concentrations of 25μM. Both quinoxaline derivatives displayed antioxidant properties and did not induce cell death in non-cancerous Raw 267.4 macrophage cells. Cytotoxicity was observed in A549 lung cancer, HeLa cervical cancer and MCF-7 breast cancer cells albeit inhibition was more pronounced in A549 lung cancer cells. Treatment of cancer cells with zinc also resulted in pronounced cytotoxicity at a minimal concentration of 25μM. Although reduced oxidative stress was observed in Raw 264.7 macrophages, in A549 lung cancer cells both compounds were able to increase ROS production which was accompanied by high levels of apoptosis when treated with derivatives and zinc alone but when in combination an improved higher level of apoptosis is observed. The improved anti-cancer activity of this drug combination treatment was further accompanied by lower Bcl/Bax expression ratios with upregulation of Bax in A549 lung cancer cells. The results of the study suggest that 3-(quinoxaline-3-yl) prop-2-ynyl methanosulphate and 3-(quinoxaline-3-yl) prop- 2-yn-1-ol are potential candidates drug for treatment of lung cancer. The use of these quinoxaline derivatives in combination with zinc can offer alternative treatment options for lung cancer. / National Research Foundation (NRF)
74

Functional and diagnostic relevance of FGFR1-dependent signaling pathways in squamous cell lung cancer

Elakad, Omar 02 September 2020 (has links)
No description available.
75

Development of a Patient Centered Outcome Questionnaire for Advanced Lung Cancer Patients

Krueger, Ellen F. 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Symptom research with advanced lung cancer patients has primarily focused on symptom severity, frequency, and distress; yet, little is known about advanced lung cancer patients’ priorities and success criteria for symptom improvement. To address these gaps in the literature, this study examined these outcomes using a modified Patient Centered Outcomes Questionnaire (PCOQ), which has largely been used with adults with chronic pain. Advanced lung cancer patients (N = 102) were recruited from the Indiana University Simon Cancer Center to participate in a one-time self-report survey, including demographic and medical questionnaires, symptom treatment history, standardized measures of symptom severity and quality of life, and the modified PCOQ focused on eight common symptoms in advanced lung cancer. Cancer information was collected from medical records. My primary aim was to evaluate the construct validity of the PCOQ. As hypothesized, symptom severity ratings on the PCOQ were positively correlated with standardized assessments of the same symptoms as well as functional status. Greater severity of most symptoms on the PCOQ was also correlated with worse quality of life, and greater severity of four symptoms was correlated with having more medical comorbidities. Positive, moderate correlations were found between the severity and importance of seeing improvement in cough, fatigue, sleep problems, and pain on the PCOQ. Patients considered low levels of symptom severity to be acceptable following symptom treatment; no differences were found across the eight symptoms. Latent profile analysis identified four patient subgroups based on the importance of seeing improvement in each of the symptoms: (1) those who rated all symptoms as low in importance (n = 12); (2) those who rated bronchial symptoms and sleep problems as low in importance and all other symptoms as moderately important (n = 29); (3) those who rated nausea and emotional distress as low in importance and all other symptoms as moderately important (n = 23); and (4) those who rated all symptoms as highly important (n = 33). These subgroups were unrelated to demographic and clinical factors, except for functional status. Findings suggest that symptom severity and importance are related yet distinct aspects of the advanced lung cancer symptom experience. Furthermore, patients have heterogeneous priorities for symptom management, which has implications for tailoring treatment.
76

Rational Design and Anti-proliferative Activity Of Substituted N,N'- bis(arylmethyl)imidazolium Salts as Varied Therapeutics

Taylor, Kerri Shelton 09 June 2016 (has links)
No description available.
77

Development and validation of a prognostic model for non-lung cancer death in elderly patients treated with stereotactic body radiotherapy for non-small cell lung cancer / 高齢非小細胞肺癌患者に対する体幹部定位放射線治療後の非肺癌死予測モデルの構築と妥当性評価

Hanazawa, Hideki 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第23784号 / 医博第4830号 / 新制||医||1057(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 鈴木 実, 教授 中島 貴子, 教授 伊達 洋至 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
78

Small cell lung cancer and cancer stem cell-like cells

Sarvi, Sana January 2014 (has links)
Small cell lung cancer (SCLC) is a highly aggressive malignancy with extreme mortality and morbidity. Although initially chemo- and radio-sensitive, almost inevitable recurrence and resistance occurs. SCLC patients often present with metastases, making surgery not feasible. Current therapies, rationally designed on underlying pathogenesis, produce in vitro results, however, these have failed to translate into satisfactory clinical outcomes. Recently, research into cancer stem cells (CSCs) has gained momentum and form an attractive target for novel therapies. Based on this concept, CSCs are the cause of neoplastic tissue development that are inherently resistant to chemotherapy, explaining why conventional therapies can shrink the tumour but are unable to eliminate the tumour completely, leading to eventual recurrence. Here I demonstrate that SCLC H345 and H69 cell lines contain a subset of cells expressing CD133, a known CSC marker. CD133+ SCLC sub-population maintained their stem cell-like phenotype over a prolonged period of culture, differentiated in appropriate conditions and expressed the embryonic stem cell marker Oct-4 indicating their stem-like phenotype. Additionally, these cells displayed augmented clonogenic efficacy, were chemoresistant and tumorigenic in vivo, distinct from the CD133- cells. Thus, the SCLC CD133 expressing cells fulfil most criteria of CSClike definition. The molecular mechanisms associated with CD133+ SCLC chemoresistance and growth is unknown. Up-regulated Akt activity, a known promoter of resistance with survival advantage, was observed in CD133+ SCLC cells. Likewise, these cells demonstrated elevated expression of Bcl-2, an anti-apoptotic protein compared to their negative counterpart explaining CD133+ cell chemoresistance phenotype. Additionally, CD133+ cells revealed greater expression of neuropeptide receptors, gastrin releasing peptide (GRP) and V1A receptors compared to the CD133- cells. Addition of exogenous GRP and arginine vasopressin (AVP) to CD133+ SCLC cells promoted their clonogenic growth in semi-solid medium, illustrating for the first time neuropeptide dependent growth of these cells. A novel peptide (peptide-1) was designed based on the known structure of the substance P analogues that have shown benefit in animal models and in early clinical trials. This compound inhibited the growth of SCLC cells in in vitro with improved potency and stability compared to previous analogues and reduced tumorigenicity in vivo. Interestingly, peptide-1 was more effective in CD133+ cells due to increased expression of neuropeptide receptors on these cells. In conclusion, my results show that SCLC cells retain a sub-population of cells that demonstrate CSC-like phenotype. Preferential activation of Akt and Bcl-2 survival pathways and enhanced expression of neuropeptide receptors contribute to CD133+ SCLC chemoresistance and growth. Therefore, it can be proposed that CD133+ cells are the possible cause of SCLC development, treatment resistance and disease recurrence. Despite being chemoresistant, CD133+ cells demonstrated sensitivity to peptide-1. The identification of such new analogue that demonstrates efficacy towards resistant CD133+ SCLC cells is a very exciting step forward in the identification of a potential new therapy for resistant disease.
79

Hedgehog-GLI Signaling Inhibition Suppresses Tumor Growth in Squamous Lung Cancer

Huang, Lingling January 2014 (has links)
<p>Lung squamous cell carcinoma (LSCC) comprises ~30% of non-small cell lung cancers, and currently lacks effective targeted therapies. Previous immunohistochemical and microarray studies reported overexpression of Hedgehog (HH)-GLI signaling components in LSCC. However, they addressed neither the tumor heterogeneity nor the requirement for HH-GLI signaling. Here, we investigated the role of HH-GLI signaling in LSCC, and studied the therapeutic potential of HH-GLI pathway suppression. </p><p>Gene expression datasets of two independent LSCC patient cohorts were analyzed to study the activation of HH-GLI signaling. Four human LSCC cell lines were examined for HH-GLI signaling components. Cell proliferation and apoptosis were assayed in these cells after blocking the HH-GLI pathway by lentiviral-shRNA knockdown or small molecule inhibitors. Xenografts in immunodeficient mice were used to determine the <italic>in vivo<italic> efficacy of GLI inhibitor GANT61. </p><p>In both patient cohorts, we found that activation of HH-GLI signaling was significantly associated with the classical subtype of LSCC. <italic>GLI2<italic> expression level was significantly higher than <italic>GLI1<italic>, and displayed strong positive correlations with the prominent markers for the classical subtype (<italic>SOX2<italic>, <italic>TP63<italic> and <italic>PIK3CA<italic>) on chromosome 3q. In cell lines, genetic knockdown of SMO produced minor effects on cell survival, while GLI2 knockdown significantly reduced proliferation and induced extensive apoptosis. Consistently, the SMO inhibitor GDC-0449 resulted in limited cytotoxicity in LSCC cells, whereas the GLI inhibitor GANT61 was very effective. Importantly, GANT61 demonstrated specific <italic>in vivo<italic> anti-tumor activity in xenograft models of GLI-positive cell lines. </p><p>Taken together, we report SMO-independent regulation of GLI in LSCC, and demonstrate an important role for GLI2 in LSCC. Different from standard-of-care chemotherapy or small molecule inhibition of kinase signaling cascades, we present a novel and potent strategy to treat a subset of LSCC patients by targeting the GLI transcriptional network.</p> / Dissertation
80

Regionales Metastasierungsmuster bei operierten Nicht-kleinzelligen Lungenkarzinomen

Moulla, Yusef 07 July 2016 (has links) (PDF)
Einteilung:Das Lungenkarzinom ist eine der häufigsten Krebstodesursachen der Welt. Die chirurgische Therapie mit onkologischer Resektion des Tumors bietet bessere Chancen für einen dauerhaften Therapieerfolg. Die Bedeutung der systematischen Lymphadenektomie im Sinne eines akkuraten Stagings und einer besseren Lokalkontrolle des Tumors ist unumstritten. In der Literatur wurden verschiedene LK-Befallsmuster bei den operierten NSCLC anhand verschiedener histomorphologischer Parameter beschrieben, um letztendlich eine passende Technik der Lymphadenektomie zu entwickeln. Patienten und Methoden: In unserer retrospektiven Studie wurde ein Kollektiv von 111 Patienten mit operierten nicht kleinzelligen Lungenkarzinome zwischen 2008 und 2013 untersucht. Das LK-Metastasierungsmuster wurde anhand verschiedener histomorphologischer Parameter untersucht. Ergebnisse: Eine zentrale Tumorlage, L1-Kategorie, sowie die zunehmende Tumorgröße zeigten eine signifikante Neigung zur LK-Metastasierung. Anhand der Tumorlokalisation im Lungenlappen ließ sich jedoch kein bestimmtes LK- Befallmuster sichern. Schlussfolgerung: Diese Daten unterstützen die Angaben der Literatur, in der eine systematische Lymphadenektomie unabhängig von den anderen Parametern weiter gefordert wird, um ein akkurates Staging zur erreichen und so eine optimale Therapie durchzuführen.fi

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