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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.
31

Perturbation of glycoprotein expression and processing in multidrug resistant cells : modulation of drug transport and cytotoxicity by Tunicamycin

Hiss, Donavon Charles 11 April 2017 (has links)
No description available.
32

A chemical-biology approach for screening novel inhibitors of focal adhesion signaling in relation to breast cancer /

Cao, Yangxiezi. January 2008 (has links)
No description available.
33

Identification, characterization and mechanistic studies of Brucein D from Brucea javanica L. as an anti-pancreatic cancer agent. / CUHK electronic theses & dissertations collection

January 2009 (has links)
In conclusion, the present study successfully demonstrate BJ as a potent anti-pancreatic cancer herb; BD is the main ingredient for its cytotoxic and apoptotic effects on the pancreatic cancer cells through activation of the redox-sensitive p38-MAPK signaling pathway and reduction of anti-apoptotic activity by inhibition of NF-kappaB activation in pancreatic cancer cells. The in vivo efficacy and low toxicity of BD render this chemical compound to be a potential for its further development into an anti-pancreatic cancer agent. / In recent decades, the application of Chinese herbal medicine has become an increasingly popular approach and alternative to treating cancer. Moreover, Chinese herbal medicine is the source for the discovery of novel anti-cancer drugs. For example, irinotecan and topotecan, the analogues of camptothecin which is isolated from the bark and stem of Camptotheca acuminate are found to be effective in ovarian, lung and colon cancers. Given that Chinese medicine is commonly used in the treatment of cancers, we postulate that Chinese herbs are a valuable source to possess anti-pancreatic cancer compounds. Accordingly, the aims of the present project are: (1) to screen Chinese medicinal herbs which has the most potent cytotoxic activity in pancreatic cancer cells in vitro; (2) to isolate and identify the effective compound in Brucea javanica (BJ) which mediates apoptosis in pancreatic cancer cell lines; (3) to study the mechanistic pathways involved in brucein D - (BD, a quassinoid found in abundance in BJ) mediated apoptosis in pancreatic cancer in vitro; and (4) to evaluate the efficacy of BD in pancreatic cancer using an xenograft animal model of pancreatic cancer. / In vivo study demonstrated that daily administration of BD through intravenous injection for ten days in nude mice bearing pancreatic cancer cells effectively reduced tumor growth in terms of tumor weight and size, while showing no significant toxicity in heart, liver and kidney tissues of the mice. / Nine Chinese medicinal herbs were selected for the screening experiment and, among them, BJ exhibited the most potent cytotoxic action on the three pancreatic adenocarcinoma cell lines, namely PANC-1, SW-1990 and CAPAN-1, with IC50 values of 2.5mug/ml, 5.1mug/ml and 1.5mug/ml, respectively. BD, one of the main chemical compounds found in BJ was found to possess strong apoptogenic effect in PANC-1 cells, as evidenced by DNA condensation and fragmentation, sub-G1 phase formation, proteolytic activation of caspase 3, 8 and 9, and attenuation of bcl-2 activity. Further mechanistic studies revealed that the apoptotic signals generated by BD were transduced from the cell membrane to nucleus via the mediation of p38-MAPK signaling pathway while the reactive oxygen species (ROS) was found to accumulate in BD-treated PANC-1 cells. The activation p38-MAPK phosphorylation was inhibited by pretreatment with an antioxidant. However, the inhibition of NF-kappaB activity and downregulation of anitapoptotic genes in BD-treated cells was independent of the ROS changes. / Pancreatic cancer is the forth and sixth leading cause of cancer deaths in the United States and Hong Kong, respectively. The morbidity of pancreatic cancer is almost equal to its mortality rate. Poor diagnosis and intrinsic resistance to chemotherapy are the major characteristics for pancreatic cancer. Therefore, new therapeutic strategy is urgently warranted to overcome the drug-resistance challenge in the management of pancreatic cancer. / Lau Sin Ting Cynthia. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 228-271). / 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, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
34

Polyphyllin D activates mitochondrial and lysosomal apoptotic pathway in drug resistant RHepG2 cells. / 甾體皂甙激活含多藥耐藥性肝癌細胞RHepG2之線粒體與溶體細胞凋亡途徑 / CUHK electronic theses & dissertations collection / Zi ti zao dai ji huo han duo yao nai yao xing gan ai xi bao RHepG2 zhi xian li ti yu rong ti xi bao diao wang tu jing

January 2007 (has links)
By using the acridine orange (AO) staining method to examine the release of contents from lysosomes, it was found that PD released AO into the cytosol in both cell lines. However, the releasing pattern of HepG2 and RHepG2 was quite different. Upon PD treatment, the release of AO in HepG2 cells was graduate and slow while that in RHepG2 was sudden and sharp. / Cancer is one of the leading causes of death in the world. During cancer treatment, development of multidrug resistance (MDR) is always the major cause of failures of chemotherapy in human cancers. In our project, hepatocarcinoma HepG2 and its drug-resistant derivatives RHepG2 with MDR towards doxorubicin (Dox), fenretinide and Taxol were used to examine the differences in their response towards various anti-cancer agents. / From the AO staining, most of the lysosomes were found in the cytosol near the nucleus. However, some lysosomes were found inside the nucleus occasionally. When we double stained the HepG2 cells with DiOC6(3), it was found that the lysosomes were actually located inside the nuclear tubules. However, no such lysosome migration was observed after treating the HepG2 cells with PD. Thus, lysosomes inside the nuclear tubules might not be involved in the PD-induced lysosomal pathway. The mechanism that leads to the migration of lysosomes into the nuclear tubules is still unclear. / From the Western blot analysis, cathepsin D (Cat D) and cathepsin L (Cat L) were both released from the lysosomes after treating the two cell lines with PD. Also, it seemed likely that Cat L was released earlier than that of cyt c. This implies that lysosomal permeabilization is an early event in apoptosis. With the use of siRNA technology, it was found that RHepG2 with the knockdown of Cat D and Cat L were more tolerant and vulnerable towards PD, respectively. These suggest that Cat D and Cat L might act oppositely in the apoptotic pathway. Furthermore, the addition of Cat D inhibitor, pepstatin A, blocked the PD-mediated cell death in RHepG2 cells further confirms that Cat D is a pro-apoptotic protein that is involved in the apoptotic pathway. / In conclusion, PD was a potent anti-cancer agent that could reverse the MDR properties of RHepG2 and kill more RHepG2 cells through lysosomal and mitochondrial apoptotic pathway. / Next, we investigated the underlying killing mechanism and found out that PD switched on both the mitochondrial and lysosomal apoptotic pathway in both cell lines. Our results indicate that PD was able to depolarize mitochondrial membrane potential and release apoptosis inducing factor (AIF) and cytochrome c (cyt c) from the mitochondria to cytosol. Also, PD was able to act on isolated mitochondria directly, causing a stronger mitochondrial membrane permeabilization and more AIF release from the RHepG2 than that of the parental cells. / Polyphyllin D (PD) is a saponin found in a tradition Chinese herb, Paris polyphylla, which has been used to treat liver cancers in China for many years. Interestingly, from the MTT assays, we found out that RHepG2 (IC50: 2.0 muM) was more sensitive towards PD when compared to that of its parental cells (IC50: 3.9 muM). To keep the MDR properties, RHepG2 cells were routinely cultured with 1.2 muM of Dox. When we cultured RHepG2 in the absence of Dox but with 1.2 muM of PD for 28 days, the Pgp expression could not be maintained. However, such high expression level of Pgp was maintained when RHepG2 cells were treated with vincristine (1.2 muM) in the absence of Dox. This indicates that vincristine was a substrate of Pgp to keep the Pgp expression in RHepG2 cells while PD was not. / When incubated with different concentrations of Dox, RHepG2 accumulated less Dox than that of its parental HepG2 cells. When probed by the antibody against P-glycoprotein (Pgp), RHepG2 showed a strong Pgp expression. With the addition of Pgp modulator, verapamil, RHepG2 accumulated more Dox. All these findings indicate that Pgp is a mediator giving rise the MDR in RHepG2 cells. However, RHepG2 had a higher resistance to Dox than its parental line even co-cultured with verapamil. RHepG2 remained viable at the intracellular Dox concentration that was toxic to HepG2 cells. These observations suggest that the MDR properties of RHepG2 involved multiple mechanisms in addition to the effect of Pgp. / Lee, Kit Ying Rebecca. / "August 2007." / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4735. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 241-253). / 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.
35

Bioactivity of chemically synthesized goniotriol and its analogues.

January 1994 (has links)
Hung Sau Ling. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 131-137). / Table of Contents --- p.1 / Acknowledgements --- p.V / Abbreviations --- p.VI / Aim of investigation --- p.IX / Abstract --- p.XI / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1 --- Cancer Chemotherapy --- p.2 / Chapter 1.2 --- Plants as sources of useful drugs --- p.4 / Chapter 1.3 --- Potent antitumor compounds found in Goniothalamus giganteus --- p.7 / Chapter 1.4 --- Brief introduction of GONIOTRIOL --- p.8 / Chapter 1.5 --- The study on the antitumor activities of the antitumor compounds --- p.9 / Chapter 1.6 --- Biochemistry study of the anticancer agents --- p.10 / Chapter Chapter 2 --- Materials and Methods --- p.18 / Chapter 2.1 --- Materials --- p.19 / Chapter 2.1.1 --- Animals --- p.19 / Chapter 2.1.2 --- "Buffers, Culture Media and Chemicals" --- p.19 / Chapter 2.1.3 --- Cell lines --- p.20 / Chapter 2.1.4 --- Dye solutions --- p.21 / Chapter 2.1.5 --- Reagents and buffers for Agarose gel --- p.21 / Chapter 2.1.6 --- Synthetic goniotriol and its derivatives --- p.21 / Chapter 2.2 --- Methods --- p.23 / Chapter 2.2.1 --- Radioactive Precursor Incorporation Assays --- p.23 / Chapter 2.2.2 --- MTT assay --- p.24 / Chapter 2.2.3 --- Neutral Red assay --- p.24 / Chapter 2.2.4 --- Isolation and preparation of cells --- p.25 / Chapter 2.2.5 --- Assay for the solvent effect --- p.25 / Chapter 2.2.6 --- Assay for the in vitro antitumor activity THC88 on different cell lines --- p.27 / Chapter 2.2.7 --- Assay of the effect of THC86 on solid sarcoma Scl80 in vivo --- p.28 / Chapter 2.2.8 --- Assay of the effect of THC86 on peritoneal Scl80 in vivo --- p.28 / Chapter 2.2.9 --- Assay of the effect of THC89 on peritoneal EAT in vivo --- p.28 / Chapter 2.2.10 --- Assay of synthetic compound (THC89 and THC87) on the mitogenic activity of spleen lymphocytes --- p.29 / Chapter 2.2.11 --- Assay of synthetic compound (THC87) on the proliferation of murine bone marrow cells from compound- treated mice --- p.30 / Chapter 2.2.12 --- "Assay of synthetic compounds (Ml, P51 and P1) on nonmalignant cell-line" --- p.31 / Chapter 2.2.13 --- Assay of antitumor activity of synthetic compound (THC86)on PU5-1.8 --- p.31 / Chapter 2.2.14 --- Assay of the cytocidal effect of THC86 --- p.32 / Chapter 2.2.15 --- "Assay on the effect of THC86 on the synthesis of DNA, RNA and protein" --- p.32 / Chapter 2.2.16 --- Direct DNA cleavage by THC86 --- p.33 / Chapter 2.2.17 --- DNA fragmentation assay / Chapter 2.2.18 --- Assay of the effect of the synthetic compound (THC86) on different growth fraction of the cells / Chapter 2.2.19 --- Mitosis Study / Chapter 2.2.20 --- Assay for the stability of the synthetic compounds / Chapter Chapter 3 --- Structure / activity relationship of the synthetic compounds --- p.36 / Chapter 3.1 --- Results --- p.37 / Chapter 3.1.1 --- In vitro antitumor activity of the synthetic compounds --- p.37 / Chapter 3.2 --- Discussion --- p.45 / Chapter Chapter 4 --- Antitumor activities of the synthetic compounds --- p.63 / Chapter 4.1 --- Results --- p.64 / Chapter 4.1.1 --- Solvent effect in the screening process --- p.64 / Chapter 4.1.2 --- The effect of the synthetic compound (THC88) on different cell lines --- p.69 / Chapter 4.1.3 --- In vivo anti-tumor activities of the synthetic compounds --- p.71 / Chapter 4.1.3a --- Effect of THC86 on solid sarcoma Sc180 in vivo --- p.71 / Chapter 4.1.3b --- Effect of THC86 on peritoneal Scl80 in vivo --- p.71 / Chapter 4.1.3c --- Effect of THC89 on peritoneal EAT in vivo --- p.72 / Chapter 4.1.4 --- Cytotoxic effect of the tested compounds on normal cells --- p.77 / Chapter 4.1.4a --- Cytotoxic effect of THC89 on normal splenocytes in vitro --- p.77 / Chapter 4.1.4b --- Effect of THC87 on the proliferation of splenocytes --- p.77 / Chapter 4.1.4c --- Effect of THC87 on the proliferation of murine bone marrow cells --- p.78 / Chapter 4.1.4d --- Cytotoxic effect on non-malignant cell-line BALB/c 3T3/A31 --- p.78 / Chapter 4.2 --- Discussion --- p.85 / Chapter Chapter 5 --- The study on the antiproliferative mechanisms of the synthetic compounds --- p.88 / Chapter 5.1 --- Results --- p.89 / Chapter 5.1.1 --- "Effect of the synthetic compounds on Cell Growth, DNA, RNA and Protein" --- p.89 / Chapter 5.1.1a --- Effect of THC86 on PU5-1.8 (macrophage-like tumor) --- p.89 / Chapter 5.1.1b --- Cytocidal effect of THC86 on EAT --- p.89 / Chapter 5.1.1c --- "Effect of the synthetic compounds on synthesis of DNA, RNA and protein" --- p.90 / Chapter 5.1.2 --- Study of the synthetic compounds on the interactions of DNA --- p.101 / Chapter 5.1.2a --- DNA cleavage assay --- p.101 / Chapter 5.1.2b --- DNA fragmentation assay --- p.101 / Chapter 5.1.3 --- Effect of the synthetic compounds on different growth fraction of the cells --- p.104 / Chapter 5.1.4 --- Mitosis study of the synthetic compounds --- p.106 / Chapter 5.1.5 --- Investigation of the stability of the synthetic compounds in culture medium --- p.112 / Chapter 5.2 --- Discussion --- p.117 / Chapter Chapter 6 --- General Discussion --- p.122 / References --- p.131
36

Establishment of a standardized sensitivity assay for gastric cancer chemotherapy.

January 2002 (has links)
Li Ka Wai Kay. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT (ENGLISH/CHINESE) --- p.ii / TABLE OF CONTENTS --- p.viii / LIST OF FIGURES --- p.xii / LIST OF APPENDICES --- p.xiii / Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Gastric carcinomas --- p.1 / Chapter 1.1a --- Epidemiology --- p.1 / Chapter 1.1b --- Classification --- p.2 / Chapter 1.1c --- TNM staging --- p.3 / Chapter 1.1d --- Prognosis --- p.4 / Chapter 1.1e --- Etiology --- p.6 / Chapter 1.1f --- Genetic alteration in gastric cancer --- p.10 / Chapter 1.2 --- Treatment --- p.16 / Chapter 1.2a --- "Surgery, chemotherapy, and others" --- p.16 / Chapter 1.2b --- Response rate of treatments in previous studies --- p.18 / Chapter 1.2c --- Chemotherapeutic Drugs --- p.21 / Chapter 1.2c (1) --- 5-fluorouracil (5-FU) --- p.22 / Chapter 1.2c (2) --- cis-diamminedichloroplatinum (Cisplatin) --- p.23 / Chapter 1.2c (3) --- Doxorubicin (Adriamycin) --- p.23 / Chapter 1.2c (4) --- Daunorubicin --- p.25 / Chapter 1.2c (5) --- Epirubicin --- p.25 / Chapter 1.2d --- Toxicity of chemotherapeutic drugs --- p.26 / Chapter 1.2d (1) --- Side effects of 5-FU --- p.26 / Chapter 1.2d (2) --- "Side effects of anthracyc lines (adriamycin, daunobicin, epuirbicin)" --- p.27 / Chapter 1.2d (3) --- Side effects of cisplatin --- p.28 / Chapter 1.3 --- Mechanisms of drug resistance --- p.28 / Chapter 1.3a --- Drug resistance --- p.28 / Chapter 1.3b --- P-glycoprotein (MDR1 gene) --- p.29 / Chapter 1.3c --- p53 tumor suppressor gene --- p.35 / Chapter 1.4 --- Chemosensitivity testing --- p.40 / Chapter 1.4a --- Original of chemosensitivity testing --- p.40 / Chapter 1.4b --- Non-clonogentic assay --- p.40 / Chapter 1.4c --- Clonogenic assay --- p.42 / Chapter 2 --- AIM OF MY STUDY --- p.44 / Chapter 3 --- MATERIALS AND METHODS --- p.45 / Chapter 3.1 --- Patients --- p.45 / Chapter 3.2 --- Tumor collection and handling procedure --- p.46 / Chapter 3.2a --- Large tumor tissue from gastrectomy --- p.46 / Chapter 3.2b --- Pseudo-biopsies --- p.47 / Chapter 3.3 --- Chemosensitivity testing --- p.48 / Chapter 3.3a --- Cell Plating --- p.48 / Chapter 3.3b --- Drug testing --- p.49 / Chapter 3.4 --- Chemosensitivity analysis --- p.50 / Chapter 3.5 --- Conformational sensitive gel electrophoresis analysis (CSGE) and single strand conformational polymorphism (SSCP) --- p.51 / Chapter 3.5a --- Preparation of genomic DNA --- p.51 / Chapter 3.5b --- PCR condition for CSGE analysis --- p.51 / Chapter 3.5c --- Scanning PCR products by CSGE --- p.52 / Chapter 3.5d --- PCR condition for SSCP analysis --- p.53 / Chapter 3.5e --- Scanning PCR products by SSCP --- p.53 / Chapter 3.6 --- Reverse transcription-polymerase chain reaction (RT-PCR) for multi-drug drug resistance (MDR1) gene --- p.54 / Chapter 3.6a --- Isolation of RNA --- p.54 / Chapter 3.6b --- cDNA synthesis --- p.55 / Chapter 3.6c --- PCR primers --- p.55 / Chapter 3.6d --- Optimalization of PCR condition for MDR1 gene expression --- p.56 / Chapter 3.6e --- PCR of β2-m gene --- p.57 / Chapter 3.6f --- PCR of MDR1 gene and analysis of its expression --- p.57 / Chapter 3.7 --- Immunohistochemistry --- p.58 / Chapter 3.7a --- Immunostaining by DO-7 --- p.58 / Chapter 3.7b --- lmmunohistochemistochemical analysis of p53 protein expression --- p.59 / Chapter 3.8 --- Statistics --- p.59 / Chapter 4. --- RESULTS --- p.60 / Chapter 4.1 --- Chemosensitivity testing --- p.60 / Chapter 4.1a --- Tests completed --- p.60 / Chapter 4.1b --- Number of cases tested for each drug --- p.60 / Chapter 4.1c --- 〇D reading of the background samples --- p.60 / Chapter 4.1d --- Dose-dependent response curve --- p.61 / Chapter 4.1e --- Unique IC50 for each tumor in each drug test --- p.61 / Chapter 4.1f --- Wide distribution of ic50 for anti-tumor drugs --- p.61 / Chapter 4.1g --- Chemosensitivity and tumor histologic type --- p.63 / Chapter 4.1h --- Correlation of ic50 with tumor stage --- p.63 / Chapter 4.2 --- Immunohistochemical staining of p53 protein (DO-7) --- p.64 / Chapter 4.2a --- p53 protein accumulation in samples --- p.64 / Chapter 4.2b --- Correlation of p53 IHC expression and chemosensitivity --- p.64 / Chapter 4.3 --- SSCP and CSGE --- p.65 / Chapter 4.3a --- Detection of abnormal band movement --- p.65 / Chapter 4.3b --- Correlation of p53 mutations with chemosensitivity --- p.66 / Chapter 4.3c --- Concordance between IHC and SSCP/CSGE --- p.66 / Chapter 4.4 --- MDR1 gene expression --- p.67 / Chapter 4.4a --- MDR1 gene expression in normal and tumors --- p.67 / Chapter 4.4b --- Correlation of MDR1 expression and chemosensitivity --- p.68 / Chapter 4.5 --- Pseudobiopsies --- p.68 / Chapter 5 --- DISCUSSION --- p.70 / Chapter 5.1 --- p53 analysis of the tumors --- p.70 / Chapter 5.1a --- Immunohistochemistry versus mutational analysis --- p.70 / Chapter 5.1b --- Methods of mutational analysis --- p.73 / Chapter 5.1c --- Comparing IHC results with previous findings --- p.77 / Chapter 5.1d --- Comparing SSCP/ CSGE results with previous findings --- p.78 / Chapter 5.1e --- Correlation of IHC and SSCP/CSGE results --- p.81 / Chapter 5.2 --- MDR1 expression --- p.85 / Chapter 5.2a --- Methods for detecting MDR1 expression --- p.85 / Chapter 5.2b --- Comparing MDR1 expression results with published data --- p.88 / Chapter 5.2c --- Correlation between chemosensitivity and MDR1 gene expression --- p.92 / Chapter 5.3 --- Chemosensitivity testing --- p.94 / Chapter 5.3a --- Chemosensitivity testing method --- p.94 / Chapter 5.3b --- The chemosensitivity results --- p.102 / Chapter 5.3c --- Chemosensitivity and MDR1 expression --- p.108 / Chapter 5.3d --- Chemosensitivity and p53 immunohistochemical expression… --- p.110 / Chapter 5.3e --- Chemosensitivity and p53 mutations --- p.112 / Chapter 5.3f --- Limitation of this study --- p.115 / Chapter 5.3g --- Pseudobiopsies and large tumor samples --- p.118 / Chapter 6. --- conclusions --- p.121 / figures / appendices / references
37

Flavonoids display differential actions on er transactivation and apoptosis in MCF-7 cells.

January 2002 (has links)
Po Lai See. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 142-152). / Abstracts in English and Chinese. / TITLE PAGE --- p.p.1 / ACKNOWLEGDEMENTS --- p.p.2 / ABSTRACT --- p.p.3 / 摘要 --- p.p.6 / TABLE OF CONTENTS --- p.p.9 / LIST OF FIGURES AND TABLES --- p.p.16 / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter 1.1 --- Estrogen and Estrogen Receptors and its Action --- p.p.18 / Chapter 1.1.1 --- Estrogen --- p.p.19 / Chapter 1.1.2 --- Estrogen Receptors --- p.p.19 / Chapter 1.1.3 --- Structural Differences between ERa and ERp --- p.p.21 / Chapter 1.1.4 --- Functional Differences --- p.p.22 / Chapter 1.1.5 --- Effects of Selective Estrogen Receptor Modulators --- p.p.22 / Chapter 1.1.6 --- Estrogen works --- p.p.23 / Chapter 1.1.7 --- Estrogen Receptors and Breast Cancer --- p.p.24 / Chapter 1.2 --- Flavonoids: Properties and Biological Activities --- p.p.25 / Chapter 1.2.1 --- Chemical Structure and Classification of flavonoids --- p.p.25 / Chapter 1.2.2 --- Biological Properties and Action Mechanism of Flavonoids… --- p.p.27 / Chapter 1.2.3 --- Flavonoids and breast cancer prevention --- p.p.27 / Chapter 1.3 --- Aims and Scopes of Investigation --- p.p.29 / Chapter CHAPTER 2 --- MATERIALS AND METHODS / Chapter 2.1 --- Chemicals --- p.p.30 / Chapter 2.1.1 --- Flavonoids --- p.p.30 / Chapter 2.1.2 --- Plasmids --- p.p.30 / Chapter 2.2 --- Mammalian cell culture --- p.p.31 / Chapter 2.2.1 --- Maintenance of cells --- p.p.31 / Chapter 2.2.2 --- Preparation of cell stock --- p.p.32 / Chapter 2.2.3 --- Cell recovery from liquid nitrogen stock --- p.p.32 / Chapter 2.3 --- Identification of estrogenic activity in flavonoids --- p.p.33 / Chapter 2.3.1 --- Steady Glo Luciferase Assay --- p.p.33 / Chapter 2.3.2 --- The Biorad Protein Assay kit (a modified Bradford method). --- p.p.33 / Chapter 2.4 --- Viability Assay --- p.p.34 / Chapter 2.5 --- ERE Luciferase reporter gene assay --- p.p.35 / Chapter 2.5.1 --- Transient transfect ion of cell using lipofectamine PLUS reagent --- p.p.36 / Chapter 2.5.2 --- Dual Luciferase Assay --- p.p.37 / Chapter 2.6 --- ERα competitive binding ASSAY --- p.p.37 / Chapter 2.7 --- Apoptotic death assay --- p.p.38 / Chapter 2.8 --- Semi-quantitative RT-PCR Assay --- p.p.40 / Chapter 2.8.1 --- "Isolation of RNA using TRIzol® Reagent (Life Technology,USA) " --- p.p.40 / Chapter 2.8.2 --- Quantitation of RNA --- p.p.41 / Chapter 2.8.3 --- First strand cDNA synthesis --- p.p.41 / Chapter 2.8.4 --- PCR reactions --- p.p.43 / Chapter 2.9 --- Flow Cytometry Analysis --- p.p.43 / Chapter 2.10 --- Total triglyceride and cholesterol measurement --- p.p.44 / Chapter 2.10.1 --- Determination of the total cholesterol --- p.p.45 / Chapter 2.10.2 --- Determination of the total triglyceride --- p.p.46 / Chapter 2.11 --- Manipulation of DNA and RNA --- p.p.46 / Chapter 2.11.1 --- Transformation of DH5α --- p.p.46 / Chapter 2.11.2 --- Mini preparation of plasmid DNA --- p.p.47 / Chapter 2.11.3 --- Preparation of plasmid DNA using QIAGEN-tip 100 midi-prep kit --- p.p.48 / Chapter 2.11.4 --- Preparation of plasmid DNA using QIAGEN-tip 10000 Giga-prep kit --- p.p.49 / Chapter 2.11.5 --- Ethanol preparation of DNA and RNA --- p.p.50 / Chapter 2.11.6 --- Agarose gel electrophoresis of DNA --- p.p.51 / Chapter 2.12 --- Statistical methods --- p.p.52 / Chapter CHAPTER 3 --- Estrogenic and antiproliferative activities on MCF-7 breast cancer cells by flavonoids / Chapter 3.1 --- Introduction --- p.p.53 / Chapter 3.2 --- Results --- p.p.56 / Screening of phytoestrogens for estrogenic activities on MELN cells --- p.p.56 / Cell proliferation activity of phytoestrogens on MCF-7 and MDA-MA231 cells --- p.p.59 / Estrogenic and antiestrogenic activity of phytoestrogens on ERα or erβ transfected hepg2 cells --- p.p.64 / Chapter 3.3 --- Discussion --- p.p.73 / Chapter Chapter 4 --- interaction of baicalein with estrogen receptors / Chapter 4.1 --- Introduction --- p.p.76 / Chapter 4.2 --- Results --- p.p.78 / Estrogen receptor competition assay --- p.p.78 / ERE-Luciferase gene reporter assay --- p.p.82 / Chapter 4.3 --- Discussion --- p.p.88 / Chapter Chapter 5 --- baicalein and genistein display differential actions on er transactivation / Chapter 5.1 --- Introduction --- p.p.90 / Chapter 5.2 --- Results --- p.p.92 / Estrogenic and antiestrogenic activities of genistein and baicalein on ER transactivation --- p.p.92 / Chapter 5.3 --- Discussion --- p.p.105 / Chapter CHAPTER 6 --- APOPTOTIC EFFECTS OF BAICALEIN ON MCF-7 AND MDA-MB-231 CELL LINES / Chapter 6.1 --- Introduction --- p.p.107 / Chapter 6.2 --- Results --- p.p.111 / ER POSITIVE MCF-7 AND ER NEGATIVE MDA-MB-231 cell death assay --- p.p.111 / "Bcl-2, Bax and PS2 mRNA expression " --- p.p.116 / Arrest at sub G1 phase of MCF-7 by baicalein --- p.p.124 / Chapter 6.3 --- Discussion --- p.p.127 / Chapter CHAPTER 7 --- BAICALEIN CAN REDUCE INTRACELLULAR cholesterol and triglceride / Chapter 5.1 --- Introduction --- p.p.129 / Chapter 5.2 --- Results --- p.p.130 / Baicalein has beneficial effect on lipid metabolism --- p.p.130 / Chapter 5.3 --- Discussion --- p.p.139 / Chapter chapter 8 --- Summary --- p.p.140 / BIBLIOGRAPHY --- p.p.142 / APPENDIX 1 ABBREVIATIONS --- p.p.153 / APPENDIX 2 PRIMER LISTS --- p.p.156 / APPENDIX 3 REAGENTS AND BUFFERS --- p.p.157
38

JMJD3 acts as a tumor suppressor by disrupting cytoskeleton in pancreatic ductal adenocarcinoma cells. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Xiao, Zhangang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 118-131). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
39

Elucidation of the roles of cyclooxygenase-2 and prostaglandin E₂ in human esophageal squamous cell carcinoma. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Yu, Le. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 171-198). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
40

Antitumor activities of ergosterol peroxide and 9,11-dehydroergosterol peroxide from Ganoderma lucidum mycelia. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Ganoderma lucidum is one of most popular medicinal mushrooms in oriental countries. The medicinal properties of Ganoderma lucidum in the treatment of various diseases have been documented for hundreds of years. In recent years, more and more attentions are paid on the studies of the action mechanisms of bioactive compounds purified from this mushroom. / In conclusion, the Ganoderma steroids EP and 9(11)-DHEP can induce caspase-dependent apoptosis in susceptible cancer cells via the mitochondria-mediated pathway. In vitro and in vivo studies suggested that these two fungal steroids have the potential to be used as natural chemopreventive agents. / Keywords: Ergosterol peroxide, 9(11)-dehydroergosterol peroxide, Ganoderma lucidum, Mycelia, Antitumor activity, Apoptosis / The antiproliferative activities of EP and 9(11)-DHEP were studied by flow cytometry. Exposure of cancer cells with these two fungal steroids resulted in an accumulation of cell population at the subG1 phase in a dosage- and time-dependent manner, indicating the induction of apoptotic cell death. Morphological apoptotic changes in HepG2 cells and A375 cells were observed using TUNEL assay and Annexin-V-FLUOS assay. The signaling pathway in apoptotic cell death induced by EP and 9(11)-DHEP involved the activation of caspase 3, 7 and 9, followed by the cleavage of PARP. In Colo201 cells, a change in the ratio of expression levels of Bcl-2/Bax was observed in cells treated with EP and 9(11)-DHEP. In A375 cells, exposure to EP and 9(11)-DHEP resulted in the release of mitochondrial cytochrome c, the down-regulation of Mcl-1 and a slight up-regulation of Bak in a dosage-dependent manner. All these results indicated that apoptotic cell death in susceptible cancer cells induced by EP and 9(11)-DHEP was via the mitochondria-mediated pathway. / The in vivo antitumor activity of EP was demonstrated. EP was shown to suppress the growth of A375 cells in a nude mice xenograft model. Further studies showed that EP induced the cleavage of PARP and enhanced the total caspase 7 gene expression in the tumor cells. / Triterpenes and steroids are two important classes of Ganoderma lucidum metabolites of low molecular mass that are responsible for the antitumor activities of the mushroom. In this study, two fungal steroids, namely, 5alpha,8alpha-epidioxy-22E-ergosta-6,22-dien-3beta-ol (ergosterol peroxide (EP)) and 5alpha,8alpha-epidioxy-22E-ergosta-6,9(11),22-trien-3beta-ol (9,11-dehydroergosterol peroxide (9(11)-DHEP)) were purified from the mycelia of Ganoderma lucidum grown under submerged culture using activity-guided purification procedures against human breast adenocarcinoma MCF-7 cells. In addition to MCF-7 cells, both of these two fungal steroids showed antiproliferative activities against other human cancer cells including hepatocellular carcinoma HepG2 cells, colorectal carcinoma Colo201 cells, esophageal squamous carcinoma KYSE cells and malignant melanoma A375 cells. However, EP and 9(11)-DHEP were less toxic to MCF-10-2A, non-tumorigenic human epithelial cells, and the normal human skin fibroblast Hs68 cells. / Zheng, Lin. / Adviser: Y. S. Wong. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0253. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 153-176). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

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