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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.
211

The anti-tumor mechanism of PPAR[gamma] activator troglitazone in human lung cancer. / CUHK electronic theses & dissertations collection

January 2006 (has links)
In conclusion, our study has demonstrated that TGZ, a synthetic PPARgamma ligand, inhibits lung cancer cells growth through cell-cycle arrest, increased cell differentiation and induction of apoptosis. In this pathway, the activation of ERK by TGZ plays a central role in promoting apoptosis, which appears to be mediated via a mitochondria-related mechanism and functions in a PPARgamma-dependent manner. The interaction between PPARgamma and ERK may create an auto-regulatory and positive feedback loop to enhance the effect of ERK whereas the activation of Akt may generate a negative regulation to control the degree of apoptosis occurred in lung cancer cells. TGZ may counteract NNK function to inhibit lung cancer cell growth in the PPARgamma-dependent manner. / Lung cancer is the world's leading cause of cancer death. Currently there is not an acceptable adjuvant or palliative treatment modalities that have been conclusively shown to prolong survival in lung cancer. Therefore, translational research to improve outcomes with this disease is critical. Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a member of the nuclear hormone receptor superfamily of ligand-activated transcription. PPARgamma ligands have been demonstrated to inhibit growth of cancer cells. The role of the PPARgamma in cell differentiation, cell cycle arrest and apoptosis has attracted increasing attention. Our study focused on the role of PPARgamma and its ligand troglitazone (TGZ) in the cell death of human lung cancer and the interaction between PPARgamma system and 4-(N-Methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a major tobacco-specific carcinogen. / The epidemic of lung cancer is directly attributable to cigarette. However, it is still not completely known the molecular pathway of cigarette smoking in the pathogenesis of lung cancer. Among the carcinogenoic chemicals of cigarette smoking, 4-(N-Methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is the most potent, which induces lung cancer in all animal species tested. Unlike PPARgamma ligands, NNK can promote cell proliferationa and growth. It is interesting to know whether PPARgamma ligands can inhibit the growth-promoting function of NNK. To address this question, we used NCI-H23 lung cancer cells as the model to study how TGZ influenced the function of NNK. Results showed that NNK stimulated cell proliferation, induced the DNA binding activity of nuclear factor-kappaB (NF-kappaB), down-regulated Bad expression, and up-regulated PPARgamma protein expressions. Inhibition of NF-kappaB nuclear translocation led to the suppression of NNK-mediated Bad expression, indicating that NNK may regulate Bad expression through the activation of NF-kappaB. TGZ significantly inhibited cell proliferation induced by NNK. Though TGZ did not affect nuclear factor-kappaB (NF-kappaB) activity, it up-regulated Bad expression. Taken together, TGZ can efficiently inhibit the proliferation of lung cancer cells induced by NNK via Bad- and PPARgamma- related pathways, which may not be directly relevant to the activity of NF-kappaB. / To elucidate the mechanism responsible for the effect of PPARgamma and TGZ on lung cancer cells, we further studied the PPARgamma molecular pathway in NCIH23 treated by TGZ. The result demonstrated that TGZ induced PPARgamma and ERK1/2 accumulation in the nucleus, where the co-localization of both proteins was found. It showed that the activation of ERK1/2 resulted in apoptosis via the mitochondrial pathway, reflecting by reduction of mitochondria membrane potential, change in Bcl-2 family members, release of cytochrome c into cytosol, and activation of caspase 9. Both PPARgamma siRNA and U0126, a specific inhibitor of ERK1/2, were able to block these effects of TGZ, suggesting that apoptosis induced by TGZ was PPARgamma- and ERK1/2-dependent. Inhibition of ERK1/2 by U0126 also led to a significant decrease in the level of PPARgamma, indicating that there was probably a positive cross-talk between PPARgamma and ERK 1/2 or an auto-regulatory feedback mechanism to amplify the effect of ERK1/2 on cell growth arrest and apoptosis. In addition to ERK1/2, TGZ also activated Akt. Interestingly, inhibition of ERK1/2 prevented the activation of Akt whereas suppression of Akt had no effect on ERK1/2, suggesting that Akt was not necessary for TGZ-PPARgamma-ERK pathway. However, the inhibition of Akt promoted the release of cytochrome c. Thus, the activation of Akt may have a negative effect on apoptosis induced by TGZ. Wortmannin, a PI3K inhibitor, inhibited TGZ-induced ERK1/2 and Akt activation, indicating that PI3K may function at the up-stream of ERK and Akt. In conclusion, our study has demonstrated that TGZ induced apoptosis in NCI-H23 lung cancer cells via a mitochondrial pathway and this pathway was PPARgamma-and ERK1/2-dependent. / We first investigated the effect of PPARgamma ligand TGZ on two human lung cancer cells (NCI-H23 and CRL-2066) and one human lung normal cell (CCL-202). The results showed that in consistence with the loss of cell viability, TGZ induced apoptosis in CRL-2066 and NCI-H23 cells but not in CCL-202 cells. TGZ up-regulated PPARgamma expression in all these three lung cell lines, especially in the cancer cells. In association of the time-dependent inhibition of the cell proliferation, TGZ down-regulated the expression of Bcl-w and Bcl-2 but activated ERK1/2 and p38, suggesting that the growth-inhibitory effect of TGZ is associated with the reduction of Bcl-w and Bcl-2 and the increase of ERK1/2 and p38 activation. SAPK/JNK activation assay showed a decreased activity in all these three cell lines treated by TGZ. It was also demonstrated that TGZ was able to activate PPARgamma transcriptionally. We conclude that TGZ inhibits the growth of human lung cancer cells via the induction of apoptosis, at least in part, in a PPARgamma-relevant manner. / Li Mingyue. / "June 2006." / Advisers: George Gong Chen; Anthony Ping Chuen Yim. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6202. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 174-207). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
212

Studies on the anti-tumour activities of banlangen alkaloids on murine neuroblastoma cells.

January 2010 (has links)
Yip, Hon Yan Kelvin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 218-242). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABBREVIATIONS --- p.ii / ABSTRACT --- p.vii / CHINESE ABSTRACT (摘要) --- p.xi / PUBLICATIONS --- p.xiv / TABLE OF CONTENTS --- p.xv / Chapter CHAPTER 1: --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Neuroblastoma --- p.2 / Chapter 1.1.1 --- An overview of neuroblastoma --- p.2 / Chapter 1.1.2 --- Epidemiology of neuroblastoma --- p.3 / Chapter 1.1.3 --- Clinical presentations of neuroblastoma --- p.5 / Chapter 1.1.4 --- Diagnosis and clinical assessment of neuroblastoma --- p.8 / Chapter 1.1.5 --- Staging of neuroblastoma --- p.10 / Chapter 1.1.6 --- Genetic aberrations of neuroblastoma --- p.12 / Chapter 1.1.7 --- Therapies of neuroblastoma --- p.15 / Chapter 1.2 --- Banlangen alkaloids --- p.20 / Chapter 1.2.1 --- An overview of Banlangen alkaloids --- p.20 / Chapter 1.2.2 --- "Pharmacokinetics of indirubin, tryptanthrin and their derivatives" --- p.24 / Chapter 1.2.2.1 --- Bioavailability of indirubin and its derivatives --- p.24 / Chapter 1.2.2.2 --- Toxicity of indirubin and its derivatives --- p.25 / Chapter 1.2.2.3 --- Bioavailability of tryptanthrin --- p.26 / Chapter 1.2.2.4 --- Toxicity of tryptanthrin --- p.27 / Chapter 1.2.3 --- "Pharmacological effects of indirubin, tryptanthrin and their derivatives" --- p.28 / Chapter 1.2.3.1 --- Selective inhibitor on kinases --- p.29 / Chapter 1.2.3.2 --- Anti-inflammatory activities --- p.31 / Chapter 1.2.3.3 --- Anti-tumour activities --- p.32 / Chapter 1.2.3.3.1 --- Anti-leukemic activity --- p.32 / Chapter 1.2.3.3.2 --- Apoptosis-inducing activity --- p.34 / Chapter 1.2.3.4 --- Anti-viral properties --- p.37 / Chapter 1.2.3.5 --- Anti-microbial properties --- p.37 / Chapter 1.3 --- Aims and Scope of This Study --- p.39 / Chapter CHAPTER 2: --- MATERIALS AND METHODS --- p.41 / Chapter 2.1 --- Materials --- p.42 / Chapter 2.1.1 --- Cell lines --- p.42 / Chapter 2.1.2 --- "Cell culture media, reagents and buffers" --- p.43 / Chapter 2.1.3 --- General staining solutions --- p.46 / Chapter 2.1.4 --- Drugs and chemicals --- p.47 / Chapter 2.1.5 --- Reagent for primary cultures preparation --- p.48 / Chapter 2.1.6 --- Reagents for cell proliferation assay --- p.48 / Chapter 2.1.7 --- Reagents for DNA extraction --- p.50 / Chapter 2.1.8 --- Reagents for gel electrophoresis of nucleic acids --- p.51 / Chapter 2.1.9 --- Reagents and buffers for flow cytometry --- p.53 / Chapter 2.1.10 --- Reagents and buffers for measuring caspase activity --- p.54 / Chapter 2.1.11 --- "Reagents, buffers and materials for Western blot analysis" --- p.58 / Chapter 2.1.12 --- Reagent for Hoechst staining --- p.68 / Chapter 2.2 --- Methods --- p.69 / Chapter 2.2.1 --- Culture of cell lines --- p.69 / Chapter 2.2.2 --- Determination of cell viability --- p.70 / Chapter 2.2.3 --- Determination of cell proliferation by tritiated thymidine ([ 3H]-TdR) incorporation assay --- p.72 / Chapter 2.2.4 --- "Isolation, culture and cytotoxicity test of murine peritoneal macrophages" --- p.73 / Chapter 2.2.5 --- "Isolation, culture and cytotoxicity test of murine bone marrow cells" --- p.74 / Chapter 2.2.6 --- Cytotoxicity test of primary cortical neurons from SD rats --- p.75 / Chapter 2.2.7 --- Determination of colony forming ability --- p.75 / Chapter 2.2.8 --- Analysis of cell cycle profile /DNA content by flow cytometry --- p.76 / Chapter 2.2.9 --- Detection of DNA fragmentation by agarose gel electrophoresis --- p.77 / Chapter 2.2.10 --- Quantitative detection of DNA fragmentation by Cell Death ELISAplus kit --- p.78 / Chapter 2.2.11 --- Detection of intracellular reactive oxygen species (ROS) generation --- p.80 / Chapter 2.2.12 --- Measurement of caspase activity --- p.81 / Chapter 2.2.13 --- Hoechst 33342 staining --- p.83 / Chapter 2.2.14 --- Cell morphological study --- p.83 / Chapter 2.2.15 --- Analysis of morphological changes by flow cytometry --- p.84 / Chapter 2.2.16 --- Assay for acetylcholine esterase (AChE) activity --- p.85 / Chapter 2.2.17 --- Protein expression study --- p.86 / Chapter 2.2.18 --- Statistical analysis --- p.89 / Chapter CHAPTER 3: --- IN VITRO STUDIES ON THE ANTI PROLIFERATIVE EFFECT OF INDIRUBIN-3'-OXIME AND TRYPTANTHRIN ON NEUROBLASTOMA CELLS --- p.90 / Chapter 3.1 --- Introduction --- p.91 / Chapter 3.2 --- Results --- p.95 / Chapter 3.2.1 --- Effects of indirubin-3'-oxime and tryptanthrin on the proliferation of human and the murine neuroblastoma cells --- p.95 / Chapter 3.2.2 --- Kinetic and reversibility studies of the anti-proliferative effect of indirubin-3'-oxime and tryptanthrin on the murine neuroblastoma Neuro-2a BU-1 cells --- p.107 / Chapter 3.2.3 --- Cytotoxic effect of indirubin-3'-oxime and tryptanthrin on the murine neuroblastoma Neuro-2a BU-1 cells --- p.115 / Chapter 3.2.4 --- Effects of indirubin-3'-oxime and tryptanthrin on the clonogenicity of the murine neuroblastoma Neuro-2a BU-1 cells --- p.120 / Chapter 3.2.5 --- Cytotoxicity of indirubin-3'-oxime and tryptanthrin on primary cells --- p.123 / Chapter 3.2.6 --- Effects of tryptanthrin on the cell cycle profile and expression of cyclins and cyclin-dependent kinases (CDKs) in the murine neuroblastoma Neuro-2a BU-1 cells --- p.132 / Chapter 3.2.7 --- Effect of indirubin-3'-oxime on the cell cycle profile in the murine neuroblastoma Neuro-2a BU-1 cells --- p.133 / Chapter 3.3 --- Discussion --- p.142 / Chapter CHAPTER 4: --- IN VITRO STUDIES ON THE APOPTOSIS-INDUCING EFFECT OF INDIRUBIN-3'-OXIME ON NEUROBLASTOMA CELLS --- p.150 / Chapter 4.1 --- Introduction --- p.151 / Chapter 4.2 --- Results --- p.156 / Chapter 4.2.1 --- Induction of DNA fragmentation in the indirubin-3'-oxime-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.156 / Chapter 4.2.2 --- Induction of chromatin condensation in the indirubin-3 '-oxime-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.160 / Chapter 4.2.3 --- Induction of caspase activities in the indirubin-3 '-oxime-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.162 / Chapter 4.2.4 --- Induction of Reactive Oxygen Species (ROS) in the indirubin-3' -oxime-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.169 / Chapter 4.2.5 --- Expression of pro-apoptotic and anti-apoptotic proteins in the indirubin-3 '-oxime-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.173 / Chapter 4.3 --- Discussion --- p.177 / Chapter CHAPTER 5: --- STUDIES ON THE DIFFERENTIATION-INDUCING ACTIVITY OF TRYPTANTHRIN ON NEUROBLASTOMA CELLS --- p.188 / Chapter 5.1 --- Introduction --- p.189 / Chapter 5.2 --- Results --- p.193 / Chapter 5.2.1 --- Effects of tryptanthrin on the cell size and cellular complexity of the murine neuroblastoma Neuro-2a BU-1 cells --- p.193 / Chapter 5.2.2 --- Morphological studies on tryptanthrin-treated murine neuroblastoma Neuro-2a BU-1 cells --- p.196 / Chapter 5.2.3 --- Effect of tryptanthrin on the acetylcholine esterase (AChE) activity in the murine neuroblastoma Neuro-2a BU-1 cells --- p.198 / Chapter 5.2.4 --- Effects of tryptanthrin on the expression of tau protein and other mediators involved in the differentiation pathway --- p.200 / Chapter 5.3 --- Discussion --- p.204 / Chapter CHAPTER 6: --- CONCLUSIONS AND FUTURE PERSPECTIVES --- p.209 / REFERENCES --- p.218
213

Targeting of the Myc pathway as a novel approach for cancer therapy /

Mo, Hao, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 3 uppsatser.
214

In vitro elucidation of the metabolic fate of the anticancer drug busulfan

Younis, Islam Rasem. January 2008 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 109 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 92-109).
215

Preclinical pharmacokinetic and tolerance assessment and phase I clinical trial of MU-gold, a novel chemotherapeutic agent /

Higginbotham, Mary Lynn, January 2004 (has links)
Thesis (M.S.)--University of Missouri--Columbia, 2004. / "May 2004." Typescript. Vita. Includes bibliographical references (leaves 40-45). Also issued on the Internet.
216

Augmentation of the differentiation response to antitumor quinolines

Rahim-Bata, Rayhana. January 2004 (has links)
Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiii, 152 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 141-149).
217

Delivery of cytotoxic agents using low density lipoprotein (LDL) : physico-chemical and biological evaluation of LDL-drug conjugates /

Kader, Abdul, January 1997 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 1997. / Restricted until June 2000. Bibliography: leaves 230-274.
218

Preclinical pharmacokinetic and tolerance assessment and phase I clinical trial of MU-gold, a novel chemotherapeutic agent

Higginbotham, Mary Lynn, January 2004 (has links)
Thesis (M.S.)--University of Missouri--Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 40-45). Also issued on the Internet.
219

DNA damage response activated by anti-cancer agent, irofulven

Wiltshire, Timothy D. January 2007 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 227 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
220

Study of anti-tumor and immunomodulatory activities of two annonaceous acetogenins: microcarpacin A and microcarpacin B. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Wu Xiujuan. / "May 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 294-314). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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