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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

Estudo de fase II avaliando eficácia e toxicidade de UFT (uracil e tegafur) e leucovorin, administrados duas vezes ao dia, no tratamento de pacientes com câncer metastático de cólon e reto / Phase II trial evaluating the efficacy and toxicity of UFT and toxicity of UFT and leucovorin twice-daily as a treatment for metastatic colorectal cancer

Hoff, Paulo Marcelo Gehm 14 March 2007 (has links)
Infusões prolongadas de 5-fluorouracil são mais seguras e potencialmente mais efetivas no tratamento do câncer de cólon metastático do que infusões rápidas da mesma medicação. No entanto, infusões prolongadas requerem a disponibilidade de um acesso venoso central, bem como de bombas de infusão dispendiosas. O desenvolvimento de fluoropirimidinas orais permitiu que pacientes fossem expostos ao 5-fluorouracil por longo tempo, com maior conveniência. UFT e leucovorin administrados três vezes ao dia demonstraram previamente uma eficácia equivalente, com menor toxicidade, quando comparados a um regime convencional de infusão rápida de 5- fluorouracil e leucovorin. Este estudo com 98 pacientes foi desenhado e conduzido com objetivo de demonstrar equivalência no tempo de progressão com o uso de UFT e leucovorin administrados duas vezes ao dia, com o uso da mesma combinação administrada três vezes ao dia. Objetivos secundários incluíram análise de toxicidade, resposta objetiva e sobrevida global. O tempo mediano de progressão foi de 3,8 meses, comparado com 3,5 meses observados com o uso da medicação três vezes ao dia e a taxa de resposta foi de 11%, com uma sobrevida mediana de 12,8 meses, sendo comparável aos resultados de 12% e 12,4 meses obtidas com o uso da combinação três vezes ao dia. A incidência de diarréia com graus 3 e 4 foi de 30% no regime de administração duas vezes ao dia, e 21% no de três vezes ao dia. Esses resultados sugerem que o uso de UFT e leucovorin duas vezes ao dia tem eficácia e toxicidade similares àquelas obtidas com o uso da mesma medicação três vezes ao dia. / Prolonged infusions have been shown to be safer and potentially more effective than bolus regimens of 5- fluorouracil as treatment for advanced colorectal cancer. However, infusional 5- fluorouracil requires central venous access and costly infusion pumps. Development of oral fluoropyrimidines has allowed longer exposures to 5-fluorouracil with increased convenience. UFT and leucovorin given thrice daily showed improved safety and no significant difference in survival or response rate compared with bolus 5- fluorouracil and leucovorin. This study with 98 patients was conducted to evaluate whether UFT and leucovorin given twice daily provided comparable time to progression (TTP) to the same combination administered three times a day. Secondary objectives included evaluation of toxicity, overall tumor response rate, and survival. Median time to progression was 3.8 months, compared with 3.5 months observed with the thrice-daily regimen. The twice-daily regimen had a response rate of 11% and median survival of 12.8 months, comparable to the 12% and 12.4 months seen with the thrice-daily regimen. The incidence of grade 3-4 drug-related diarrhea was 30% on the twice-daily and 21% on the thrice-daily schedule. Results suggest that the twice-daily schedule has similar safety and efficacy to the thrice-daily schedule.
72

"Valor prognóstico e preditivo da expressão imunoistoquímica de timidilato sintase em pacientes portadores de adenocarcinoma colorretal" / Prognostic and predictive value of the immunohistochemical expression of thymidylate synthase in patients with colorectal carcinoma

Aguiar Junior, Samuel 02 April 2004 (has links)
O objetivo do estudo foi estudar a expressão de timidilato sintase (TS) como fator preditivo para eficácia de quimioterapia adjuvante com 5-fluorouracil (5-FU) e como fator prognóstico para sobrevida em pacientes portadores de câncer colorretal. Trata-se de estudo retrospectivo em uma série de 114 pacientes com carcinoma colorretal estádios II ou III, distribuídos em dois grupos: 1)cirurgia exclusiva (n=61); 2)cirurgia seguida de quimioterapia com 5-FU (n=53). A expressão de TS foi determinada por imunoistoquímica. Observou-se que a expressão intratumoral de TS foi capaz de selecionar pacientes que se beneficiaram com emprego de quimioterapia adjuvante, mas não se mostrou como variável independente para risco de recidiva ou óbito / The purpose of this study was trying to assess the value of TS expression as a predictive factor in the efficacy of adjuvant chemotherapy in colorectal cancer, as well as its independent prognostic value for survival. It deals with a retrospective study that assesses a series of 114 individuals with high risk colorectal cancer, distributed into two different groups: 1)surgery alone (n=61); 2)surgery and 5-FU-based chemotherapy (n=53). TS expression was determined by immunohistochemistry. We observed that TS expression may select patients that benefit from adjuvant chemotherapy, but it was not shown as an independent variable for the risk of recurrence or death
73

Lovastatin sensitizes the trail-induced apoptosis in human glioblastoma: how does it work?. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Liu, Pi-chu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 155-173). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
74

Modulation of cytochrome P450 1 activity and DMBA-DNA adduct formation by baicalein, isoflavones and theaflavins.

January 2002 (has links)
Chan Ho Yee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 121-138). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.II / ABSTRACT --- p.III / 摘要 --- p.V / ABBREVIATIONS --- p.VI / "TABLE OF CONTENTS, " --- p.VII / LIST OF FIGURES AND TABLES --- p.XI / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / Xenobiotic-metabolizing enzymes --- p.1 / Cytochrome P450 1 family --- p.4 / CYP1A1 --- p.5 / CYP1A2 --- p.5 / CYP1B1 --- p.5 / Transactivation of CYP1 enzymes by Aryl hydrocarbon receptor (AhR) --- p.8 / Implication of PAHs and CYP1 family in breast cancer --- p.10 / Potential role of phytochemicals on cancer prevention --- p.11 / Significance of this project --- p.13 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.14 / Chemicals --- p.14 / Maintenance of cells --- p.14 / Preparation of cell stock --- p.14 / Cell recovery from liquid nitrogen stock --- p.15 / Measurement of cell viability --- p.15 / Preparation of cell lysates (NP-40 cell lysis buffer) --- p.15 / XRE-luciferase gene reporter assay --- p.16 / Manipulation of DNA and RNA --- p.17 / Separation and purification of DNA from agarose gel --- p.17 / Separation of DNA from acrylamide gel --- p.17 / Restriction digestion --- p.18 / Ligation of DNA fragments --- p.18 / Transformation of DH5 a --- p.19 / Small scale plasmid purification from DH5a (mini prep) --- p.19 / Large scale plasmid isolation from DH5a (maxi-prep) --- p.20 / Construction of XRE activated luciferase reporter gene --- p.21 / Measurement of DMBA-DNA adduct formation --- p.21 / Semi-quantitative RT-PCR Assay --- p.22 / ENZYME ACTIVITIES --- p.23 / Isolation of microsomes --- p.23 / EROD activities in intact cells --- p.23 / EROD inhibition assay --- p.24 / Stattstical Analysis --- p.24 / Chapter CHAPTER 3 --- BAICALEIN INHIBITS DMBA-DNA ADDUCT FORMATION BY MODULATING CYP1A1 AND 1B1 ACTIVITIES --- p.26 / Introduction --- p.26 / Results --- p.28 / EROD activities in MCF-7 cells and inhibition assay --- p.28 / Baicalein suppressed DMBA-induced XRE-driven luciferase activities --- p.31 / Baicalein inhibited DMBA-induced CYP1A1 and CYP1B1 mRNA expression --- p.31 / The cytotoxic effect of DMBA was reduced by baicalein --- p.35 / Inhibition of DMBA-DNA adduct formation after baicalein treatment --- p.35 / Discussion --- p.39 / Chapter CHAPTER 4 --- INHIBITION OF DMBA-DNA ADDUCT FORMATION BY (-)-EPIGALLOCATECHIN GALLATE AND THEAFLAVINS --- p.41 / Introduction --- p.41 / Results --- p.45 / Persistence of DMBA-induced DNA adducts --- p.45 / Inhibition of theaflavins and EGCG on human recombinant CYP1A1 and CYP1B1 enzyme activities --- p.48 / EGCG suppressed DMBA-induced EROD activity while thealfavin had no significant effect on this --- p.48 / Kinetic analysis of EGCG on CYP1A1 and CYP1B1 activities --- p.53 / Modulation of DMBA-induced XRE-driven luciferase activities by theaflavins and EGCG --- p.56 / The influence of theaflavins and EGCG on CYP1A1 and CYP1B1 abundance --- p.56 / Discussion --- p.65 / Chapter CHAPTER 5 --- ISOFLAVONES PREVENT DMBA-INDUCED CARCINOGENESIS BY INHIBITING CYP1A1 AND CYP1B1 ACTIVITIES --- p.67 / Introduction --- p.67 / Results --- p.70 / Isoflavones inhibited DMBA-induced EROD activity in MCF-7 cells --- p.70 / Inhibition of MCF-7 microsomal EROD activities by isoflavones --- p.70 / Kinetic analysis of the inhibition of human recombinant CYP1 enzymes by isoflavones --- p.74 / XRE-driven Luciferase activities --- p.83 / Both biochanin A and genistein suppressed DMBA-induced CYP1 mRNA expression --- p.83 / Cytotoxicity of DMBA and isoflavones co-treatment --- p.88 / Isoflavones reduced the binding of activated DMBA to DNA --- p.89 / Discussion --- p.93 / Chapter CHAPTER 6 --- IN VITRO EFFECTS OF BAICALEIN AND THEAFLAVINS ON RAT HEPATIC P450 ACTIVITIES --- p.96 / Introduction --- p.96 / Results --- p.98 / Inhibition of EROD and MROD activities in rat liver microsomes by baicalein --- p.98 / Effects of theaflavins on EROD and MROD activities in rat liver microsomes --- p.102 / Kinetic studies for EROD and MROD activities of theaflavins --- p.104 / DISCUSSION --- p.114 / Chapter CHAPTER 7 --- CONCLUSION --- p.116 / APPENDIX 1 PRIMER LISTS --- p.118 / APPENDIX 2 REAGENTS --- p.119 / BIBLIOGRAPHY --- p.121
75

Applications of evolutionary algorithms on biomedical systems.

January 2007 (has links)
Tse, Sui Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 95-104). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.1.1 --- Basic Concepts and Definitions --- p.2 / Chapter 1.2 --- Evolutionary Algorithms --- p.5 / Chapter 1.2.1 --- Chromosome Encoding --- p.6 / Chapter 1.2.2 --- Selection --- p.7 / Chapter 1.2.3 --- Crossover --- p.9 / Chapter 1.2.4 --- Mutation --- p.10 / Chapter 1.2.5 --- Elitism --- p.11 / Chapter 1.2.6 --- Niching --- p.11 / Chapter 1.2.7 --- Population Manipulation --- p.13 / Chapter 1.2.8 --- Building Blocks --- p.13 / Chapter 1.2.9 --- Termination Conditions --- p.14 / Chapter 1.2.10 --- Co-evolution --- p.14 / Chapter 1.3 --- Local Search --- p.15 / Chapter 1.4 --- Memetic Algorithms --- p.16 / Chapter 1.5 --- Objective --- p.17 / Chapter 1.6 --- Summary --- p.17 / Chapter 2 --- Background --- p.18 / Chapter 2.1 --- Multiple Drugs Tumor Chemotherapy --- p.18 / Chapter 2.2 --- Bioinformatics --- p.22 / Chapter 2.2.1 --- Basics of Bioinformatics --- p.24 / Chapter 2.2.2 --- Applications on Biomedical Systems --- p.26 / Chapter 3 --- A New Drug Administration Dynamic Model --- p.29 / Chapter 3.1 --- Three Drugs Mathematical Model --- p.31 / Chapter 3.1.1 --- Rate of Change of Different Subpopulations --- p.32 / Chapter 3.1.2 --- Rate of Change of Different Drug Concen- trations --- p.35 / Chapter 3.1.3 --- Toxicity Effects --- p.35 / Chapter 3.1.4 --- Summary --- p.36 / Chapter 4 --- Memetic Algorithm - Iterative Dynamic Program- ming (MA-IDP) --- p.38 / Chapter 4.1 --- Problem Formulation: Optimal Control Problem (OCP) for Mutlidrug Optimization --- p.38 / Chapter 4.2 --- Proposed Memetic Optimization Algorithm --- p.40 / Chapter 4.2.1 --- Iterative Dynamic Programming (IDP) . . --- p.40 / Chapter 4.2.2 --- Adaptive Elitist-population-based Genetic Algorithm (AEGA) --- p.44 / Chapter 4.2.3 --- Memetic Algorithm 一 Iterative Dynamic Programming (MA-IDP) --- p.50 / Chapter 4.3 --- Summary --- p.56 / Chapter 5 --- MA-IDP: Experiments and Results --- p.57 / Chapter 5.1 --- Experiment Settings --- p.57 / Chapter 5.2 --- Optimization Results --- p.61 / Chapter 5.3 --- Extension to Other Mutlidrug Scheduling Model . --- p.62 / Chapter 5.4 --- Summary --- p.65 / Chapter 6 --- DNA Sequencing by Hybridization (SBH) --- p.66 / Chapter 6.1 --- Problem Formulation: Reconstructing a DNA Sequence from Hybridization Data --- p.70 / Chapter 6.2 --- Proposed Memetic Optimization Algorithm --- p.71 / Chapter 6.2.1 --- Chromosome Encoding --- p.71 / Chapter 6.2.2 --- Fitness Function --- p.73 / Chapter 6.2.3 --- Crossover --- p.74 / Chapter 6.2.4 --- Hill Climbing Local Search for Sequencing by Hybridization --- p.76 / Chapter 6.2.5 --- Elitism and Diversity --- p.79 / Chapter 6.2.6 --- Outline of Algorithm: MA-HC-SBH --- p.81 / Chapter 6.3 --- Summary --- p.82 / Chapter 7 --- DNA Sequencing by Hybridization (SBH): Experiments and Results --- p.83 / Chapter 7.1 --- Experiment Settings --- p.83 / Chapter 7.2 --- Experiment Results --- p.85 / Chapter 7.3 --- Summary --- p.89 / Chapter 8 --- Conclusion --- p.90 / Chapter 8.1 --- Multiple Drugs Cancer Chemotherapy Schedule Optimization --- p.90 / Chapter 8.2 --- Use of the MA-IDP --- p.91 / Chapter 8.3 --- DNA Sequencing by Hybridization (SBH) --- p.92 / Chapter 8.4 --- Use of the MA-HC-SBH --- p.92 / Chapter 8.5 --- Future Work --- p.93 / Chapter 8.6 --- Item Learned --- p.93 / Chapter 8.7 --- Papers Published --- p.94 / Bibliography --- p.95
76

Microarray and biochemical analysis of lovastatin-induced apoptosis in human glioblastoma cells: synergism with TRAIL.

January 2006 (has links)
Chan Yiu Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 123-149). / Abstracts in English and Chinese. / Abstracts --- p.I / Acknowledgements --- p.VIII / List of Figures --- p.IX / Lists of Abbreviations --- p.X / Contents --- p.XII / Chapter Chapter One: --- Introduction and Literature Review --- p.1 / Chapter 1.1 --- Cancer in General --- p.1 / Chapter 1.2 --- Glioma --- p.3 / Chapter 1.2.1 --- Types of Glioma --- p.6 / Chapter 1.2.1.1 --- Astrocytomas --- p.6 / Chapter 1.2.1.2 --- Oligodendrogliomas --- p.8 / Chapter 1.2.1.3 --- Ependymomas --- p.9 / Chapter 1.2.2 --- Glioblastoma Multiforme (GBM) --- p.10 / Chapter 1.2.3 --- Molecular Biology of GBM --- p.11 / Chapter 1.2.4 --- Current Treatment for GBM --- p.15 / Chapter 1.3 --- HMG-Co A reductase inhibitors --- p.17 / Chapter 1.3.1 --- Pharmacology of HMG-Co A reductase inhibitor --- p.18 / Chapter 1.3.2 --- Epidemiological link between HMG-Co A Reductase Inhibitors and Cancer --- p.20 / Chapter 1.3.3 --- Current HMG-Co A reductase inhibitors research in cancer --- p.21 / Chapter 1.3.3.1 --- Inhibition of tumor cell growth --- p.21 / Chapter 1.3.3.2 --- Inhibition of Angiogenesis --- p.22 / Chapter 1.3.3.3 --- Anti-invasive effects of HMG-Co A reductase inhibitors.… --- p.23 / Chapter 1.3.3.4 --- Apoptosis induction by HMG-Co A reductase inhibitors --- p.24 / Chapter 1.3.4 --- In vivo efficacy and synergistic effects --- p.25 / Chapter 1.4 --- Tumor Necrosis Factor (TNF) related apoptosis-inducing Ligand (TRAIL) --- p.28 / Chapter 1.4.1 --- Molecular mechanisms of TRAIL-induced apoptosis --- p.29 / Chapter 1.4.2 --- Role for TRAIL in cancer therapy --- p.30 / Chapter 1.5 --- Objectives --- p.34 / Chapter Chapter 2 --- Methods and Materials --- p.35 / Chapter 2.1 --- Cell culture --- p.35 / Chapter 2.2 --- Cell proliferation detection (MTT) methods --- p.36 / Chapter 2.3 --- "Caspase 3,9 activities induced by lovastatin" --- p.37 / Chapter 2.4 --- Detection of apoptosis by Annexin V and PI staining --- p.39 / Chapter 2.5 --- Cell cycle analysis protocols --- p.41 / Chapter 2.6 --- DNA fragmentation ELISA detection kit protocols --- p.42 / Chapter 2.7 --- Reverse Transcription (RT) Polymerase Chain Reaction (PCR) --- p.44 / Chapter 2.8 --- Polymerase Chain Reaction (PCR) --- p.46 / Chapter 2.9 --- Bio-molecules extraction/purification protocols --- p.48 / Chapter 2.10 --- "Microarray analysis on lovastatin treated glioblastoma cells A172, M059J and M059K" --- p.51 / Chapter 2.10.1 --- Cells treatment and RNA extraction --- p.51 / Chapter 2.10.2 --- Synthesis of first strand cDNA --- p.53 / Chapter 2.10.3 --- Synthesis of second strand cDNA --- p.54 / Chapter 2.10.4 --- Purification of double stranded cDNA --- p.54 / Chapter 2.10.5 --- Synthesis of cRNA by in vitro transcription (IVT) --- p.55 / Chapter 2.10.6 --- Recovery of biotin-labelled cDNA --- p.56 / Chapter 2.10.7 --- Fragmentation of cRNA --- p.56 / Chapter 2.10.8 --- Preparation of hybridization reaction mixtures --- p.57 / Chapter 2.10.9 --- Loading of reaction mixtures into bioarray chambers --- p.58 / Chapter 2.10.10 --- Hybridization --- p.58 / Chapter 2.10.11 --- Post-hybridization wash --- p.59 / Chapter 2.10.12 --- 2.11.12Detection with streptavidin-dye conjugate --- p.59 / Chapter 2.10.13 --- Bioarray scanning and analysis --- p.61 / Chapter Chapter 3: --- Results --- p.62 / Chapter 3.1 --- Morphological effects of Lovastatin on human glioblastoma cells --- p.62 / Chapter 3.2 --- Anti-proliferation effects on glioblastoma cell lines --- p.64 / Chapter 3.3 --- Lovastatin-induced caspase3 and 9 activation in human glioblastoma cell lines --- p.69 / Chapter 3.4 --- Cell cycle determination by PI staining --- p.77 / Chapter 3.5 --- Quantification of apoptotic cell death by annexin V and propidium iodide staining --- p.79 / Chapter 3.6 --- Microarray analysis of lovastatin-modulated gene expression profiles --- p.82 / Chapter 3.7 --- Synergistic effects induced by lovastatin and Tumor Necrosis Factor related apoptosis-inducing Ligand (TRAIL) --- p.87 / Chapter 3.7.1 --- M059J and M059K glioblastoma cells was resistant to TRAIL attack --- p.87 / Chapter 3.7.2 --- Synergistic cell death was induced by lovastatin and TRAIL --- p.87 / Chapter 3.7.3 --- A combination of TRAIL and lovastatin induces synergistic apoptosis in glioblastoma cells --- p.93 / Chapter 3.7.4 --- DNA fragmentation on glioblastoma cells --- p.98 / Chapter 3.7.5 --- Four TRAIL receptors mRNA expression profiles on glioblastoma cells --- p.102 / Chapter Chapter 4 --- Discussion --- p.105 / Chapter 4.1 --- Lovastatin exhibited anti-proliferation effects in human glioblastoma cells --- p.107 / Chapter 4.2 --- Lovastatin activated caspase 3 and caspase 9 in human glioblastoma cells --- p.108 / Chapter 4.3 --- Gene expression profile modulated by Lovastatin in human glioblastoma cells --- p.110 / Chapter 4.4 --- Lovastatin-sensitized TRAIL-induced apoptosis in human glioblastoma cells --- p.117 / Chapter Chapter Five: --- Conclusion and Future perspective --- p.121 / References --- p.122 / Appendix --- p.150
77

Selenocystine induces mitochondrial-mediated apoptosis in breast carcinoma MCF-7 cells and melanoma A-375 cells with involvement of p53 phosphorylation and reactive oxygen species. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Additionally, we showed that SeC induced S-phase arrest in MCF-7 cells associated with a marked decrease in the protein expression of cyclin A, D1 and D3 and cyclin-dependent kinases (CDK) 4 and 6, with concomitant induction of p21waf1/Cip1, p27Kip1 and p53. Expose of MCF-7 cells to SeC resulted in delayed onset of apoptosis as evidenced by caspase activation, PARP cleavage and DNA fragmentation. SeC treatment also triggered the activation of JNK, p38 MAPK, ERK and Akt phosphorylation. Inhibitors of ERK (U0126) or Akt (LY294002), but not JNK (SP600125) and p38 MAPK (SB203580), significantly suppressed SeC-induced S-phase arrest and apoptosis in MCF-7 cells. In conclusion, our findings establish a mechanistic link between the PI3K/Akt pathway, MAPK pathway and SeC-induced cell cycle arrest and apoptosis in human breast cancer cells. (Abstract shortened by UMI.) / The role of selenium as potential cancer chemopreventive and chemotherapeutic agents has been supported by epidemiological, preclinical and clinical studies. Although cell apoptosis has been evidenced as a critical mechanism mediating the anticancer activity of selenium, the underlying molecular mechanisms remain elusive. In the present study, selenocystine (SeC), a novel organic selenocompound, is identified as a novel antiproliferative agent with a broad spectrum of inhibition against eight human cancer cell lines with the IC50 values ranged from 3.6 to 37.0 muM. Despite this potency, SeC was relatively nontoxic toward HS68 human fibroblasts with an IC 50 value exceeded 400 muM. Further investigation on the molecular mechanisms indicated that SeC induced caspase-independent apoptosis in MCF-7 breast carcinoma cells, which was accompanied by poly(ADP-ribose) polymerase (PARP) cleavage, caspase activation, DNA fragmentation, phosphatidylserine exposure and nuclear condensation. Moreover, SeC induced the loss of mitochondrial membrane potential (DeltaPsim) by regulating the expression and phosphorylation of pro-surivival and pro-apoptotic Bcl-2 family members. Loss of DeltaPsim led to the mitochondrial release of cytochrome c and apoptosis-inducing factor (AIF) which subsequently translocated into the nucleus and induced chromatin condensation and DNA fragmentation. MCF-7 cells exposed to SeC shown increase in total p53 and phosphorylated p53 on serine residues of Ser15, Ser20, and Ser392 prior to mitochondrial dysfunction. Silencing and attenuation of p53 expression with RNA interference and pifithrin-alpha treatment respectively, partially suppressed SeC-induced cell apoptosis. Furthermore, generation of reactive oxygen species (ROS) and subsequent induction of DNA strand breaks were found to be upstream cellular events induced by SeC. The thiol-reducing antioxidants, N-acetylcysteine and glutathione, completely blocked the initiation and execution of cell apoptosis. Taken together, these results suggest that SeC, as a promising anticancer selenocompound, induces caspase-independent apoptosis in MCF-7 cells mediated by ROS generation and p53 phosphorylation through regulating the mitochondrial membrane permeability. / Chen, Tianfeng. / Adviser: Yun-Shing Wong. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3260. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 124-136). / 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.
78

Studies of the active constituents of Angelica sinensis and Garcinia hanburyi on colon cancer. / 當歸及藤黃的活性成分對大腸癌的抗癌作用研究 / CUHK electronic theses & dissertations collection / Dang gui ji teng huang de huo xing cheng fen dui da chang ai de kang ai zuo yong yan jiu

January 2010 (has links)
Colorectal cancer is the second leading cause of cancer-related mortality in Hong Kong and lack of selectivity has limited the success of conventional chemotherapy. Given the recent interest in the anti-cancer effects of traditional Chinese medicine (TCM), there are two approaches to studying its bioactivity: as a mixture of ingredients or as single compounds. The objective of the present study is to examine the anti-tumor effects of Angelicae Sinensis Radix (DG) and Garcinia hanburyi resin (TH) using both approaches, respectively, as they are traditionally used to treat inflammation. In the present study, their anti-cancer effects and the mechanisms of actions were examined for the development of potential novel chemotherapeutic drugs for colon cancer since inflammation is a predisposing factor for colon cancer. / DG extract and its three main bioactive phtbalides: n-butylidenephthalide, senkyunolide A and z-ligustilide (LGT), were found to be cytotoxic to HT-29 cells with IC50 values (24 h) of 20.70 +/- 0.85, 72.51 +/- 8.65, 18.74 +/- 1.14 and 41.98 +/- 3.64 mug/ml, respectively. The results evidenced that LGT induced G0/G 1 arrest and apoptosis, triggering cleavage of PARP, pro-caspases-3, -8 and -9 and nuclear fragmentation. LGT and cisplatin synergistically reduced the viability of HT-29 cells. More interestingly, DG extract was more potent than individual phthalides, suggesting that there are other bioactive components and/or synergistic interactions. / Individual compounds purified from TH were investigated because gambogic acid isolated from this herb has been used clinically to treat cancer, 30-Epicambogin (EPC) and guttiferone K (GUTK) showed the highest cytotoxic selectivity and potency on HT-29 cells among 15 isolated compounds. IC50 values (24 h) for EPC and GUTK in HT-29 cells were 5.36+/-0.25 and 5.39+/-0.22 muM, respectively, and both induced G0/G1 arrest by down-regulation of cyclins D1, D3, CDK4 and CDK6, while up-regulation of p21Waf1/CiP1 and p27KiP1. Both compounds triggered the activation of caspases-3, -8 and -9 in apoptosis. The in vivo anti-tumor effects of GUTK were further investigated by using a subcutaneous Colon-26 mouse tumor model. GUTK (10 mg/kg i.p.) reduced tumor volume by 33.6% and potentiated the anti-tumor effects of 5-fluorouracil when administered concurrently. / Our findings revealed that DG rather than individual phthalides, is worthy for further study as a potential anti-cancer drug, due to the synergistic interactions among multi-components in the herb. On the other hand, EPC and GUTK, isolated from TH have potential to be developed as novel anti-tumor candidates for combination use with 5-fluorouracil. The results strongly support the use of different approaches to study TCM for chemotherapy, according to its traditional and empirical use. / Subsequently, the anti-proliferative effects of DG and Chuanxiong Rhizoma (CX) extracts and mixtures containing three phthalides in the proportions similar to their presence in both extracts were examined, since CX also contains the same phthalides, but in different proportions. DG extract was significantly more potent than its corresponding phthalide mixture to inhibit cancer cell proliferation and synergistic interaction was observed among the phthalides and other bioactive components, while the phthalides in CX extract interacted antagonistically with other components. / Kan, Lai Ting Winnie. / Adviser: Ge Lin. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 267-311). / 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.
79

Clinical observation and experimental study of the efficacy of a Chinese medicine formula on maligant tumour bone metastasis diseases. / 中藥配方對惡性腫瘤骨轉移作用的臨床和實驗研究 / CUHK electronic theses & dissertations collection / Clinical observation and experimental study of the efficacy of a Chinese medicine formula on malignant tumour bone metastasis diseases. / Zhong yao pei fang dui e xing zhong liu gu zhuan yi zuo yong de lin chuang he shi yan yan jiu

January 2006 (has links)
At present, there is no cure for bone metastasis. The current goals in patient care are to palliate pain, prevent pathological bone fracture and increase the strength and function of bone, so as to extend the life expectancy and maintain a good quality of life. Bisphosphonate treatment is the currently standard therapy of bone metastasis and is commonly used by physicians; it alleviates the tumour-induced hypercalcemia in 90% of patients and reduces the metastatic bone pain in 50% of patients. Moreover, it also prevents the pathological fracture of the affected bones. However, while effective, bisphosphonate injections are very costly, though its oral formulation is less expensive it is also less efficacious, and causes gastrointestinal discomfort. Furthermore, prolonged use of bisphosphonate treatment may lead to certain adverse effects, including hypocalcemia. These factors will prohibit the longterm use of such medication as it can negatively affect the treatment outcome. / Based on enormous medical potentials illustrated by the aforementioned findings, BBYNG deserves wider clinical application, large-scale clinical study on its preventive effect against bone metastasis and detailed investigation of its mode(s) of action in the body. / Based on the above-described understanding of Chinese medicine and bone metastasis, supplementing the kidney and strengthening bone could be the basic principle for the treatment of bone metastasis using Chinese medicine. In view of this theory, and in addition to the clinical observation and a thorough search of the available literature, we selected relevant kidney-tonifying Chinese herbs, namely (Fructus Ligustri Lucidi), (Rhizoma Drynariae), (Herba Epimedii), (Psoralea Corylifolia) and wide-spectrum anticancer herbs (Herba Hedyotidis Diffusae) for the preparation of a combined formula--BBYNG. / Chinese medicine has long been used to treat cancers. Its advantages reside in its holistic properties, which bring palliative, corrective and convalescing functions against damage caused by radiotherapy, chemotherapy and surgery. These features position Chinese medicines as the adjuvant to orthodox cancer treatment. During the late stage of tumour development, when standard therapy is no longer effective, Chinese medicine plays a critical role as an integrated therapy. Searching for a safe, inexpensive and effective Chinese medicine preparation suitable for prolonged use as adjunct therapy in late cancer cases is of paramount importance. / Clinical results. Both Chinese medicine and Western medicine treated patients showed no significant change in their blood parameters or liver and kidney examinations before and after drug administration; Male subjects on BBYNG, their bone mass density remained stable after 6 months treatment and the subjects on OSTAC showed slightly decreased In females, subjects on BBYNG remained stable, but subjects on OSTAC slightly increased. / Clinical study. The study was designed as a randomized, parallel-group comparison between BBYNG formula and Bisphosphonate. The patients who meet the inclusion/exclusion criteria were randomly assigned to receive either BBYNG granules, which was prepared by a GMP manufacturer, or Clodronic acid. The treatment period was 6 months (24 weeks). For both groups, various clinical parameters such as body functions, blood examinations, bone density (BMD) assessment, X-ray examinations, pain intensity and quality of life were evaluated and compared. / Conclusions. (1) As an adjuvant to patients with bone metastases, BBYNG is effective in relieving the metastatic bone pain, improving the quality of life. (2) In the animal model, BBYNG reduced the metastatic bone damage, prolonged the survival and enhanced the T lymphocyte immunity in the tumour-bearing mice. (3) In vitro study on the breast and lung cancer cell lines showed that BYYNG could induce apoptosis and prevent tumour cell invasion. It suggests that BYYNG may restrict tumour growth and development, thus reducing the occurrence of bone metastasis. / In accordance with Chinese medicine, bone metastasis can be categorized into "bone tumour" "bone erosion" "bone wilting" "bone necrosis" and "bone impediment". The main cause of bone metastasis is twofold: cancer toxicity, and in Chinese medicine theory, the kidney governs the bone marrow, if the kidney is not functioning in balance, then the bone will become weak. Cancer toxicity is the "pathogenic cause" to skeletal metastases, while kidney weakness decreases the body defence against the cancer. A vicious cycle ensues when cancer and kidney deficiency and bone weakness occurs simultaneously coincidently and worsens the conditions. / In vitro study on tumour cell lines. The anticancer effects of different concentrations of BBYNG formula and various single components against human breast cancer and lung cancer cell lines were evaluated by cell viability test (MTT assay), cell apoptosis test and invasion suppression test. / In vitro study results. BBYNG and the aqueous extracts of its component herbs at very low drug concentrations stimulated the growth of three tumour cell lines tested. When the concentrations were slightly increased, they showed an inhibitory effect on cancer cell proliferation. As the drug concentrations further increased, the extracts showed cytotoxic effects on these tumor cells. At the noncytotoxic dose, the extracts could trigger apoptosis and enhance the caspase-3 activity in all three tumour cell lines. In addition, at this "non toxic" concentration, the extracts markedly inhibited the in vitro invasive property of the 4T1 breast cancer cell lines in our Matrigel invasion model. Thus these in vitro results suggested that BBYNG possess anticancer, invasion-inhibitory and anti-metastatic activities. / In vivo animal study results. (Tumour growth was slower in the BBYNG treatment group when compared to the OSTAC and control groups, but this was not significantly difference) BBYNG significantly delayed tumour growth in tumour bearing mice, but it did not minimize the tumour size markedly. Moreover, BBNYG did minimize the mobility restriction caused by tumours, reduce the damage to bones, prolong the survival time and enhanced the T lymphocyte immunity. / In vivo animal study. A well-established animal model for breast cancer was used to evaluate and compare the pharmacological effects of BBYNG formula and Clodronic acid, as shown by different indicators such as tumour progression, animal's mobility, survival time, bone metastasis-induced fracture intensity and the immunological status of the tumour-bearing mice. / Malignant tumour is characterized by early metastasis. Among them 37 to 80 (depending on which type of cancer) patients show tendency of bone metastasis. Bone metastasis is usually accompanied by various complications, such as severe pain, pathological bone fracture, hypercalcemia, and bone marrow suppression, which can substantially affect the quality of life of the patients. Thus, the prevention and treatment of bone metastasis in cancer is an issue worth pursuing. / Malignant tumours leading to high mortality and morbidity are a serious threat to human health. It is the leading cause of death in China. In Hong Kong, there are over 20 thousand new cancer cases and more than 1100 people die due to cancers every year. / Study objectives. To elucidate the efficacy and some pharmacological aspects of BBYNG in regard to the treatment of bone metastasis through clinical observation and different laboratory experiments. This study would be of significant reference value to the disease-oriented drug formulation and application, mechanistic study and research methodology of the treatment of bone metastasis using Chinese medicines. / The clinical and laboratory experimental results are summarized as below: / The research study is composed of three parts, the clinical study, in vivo animal study and in vitro study on tumour cell lines. The research methods used are as follows: / Those on BBYNG treatment showed more a stable and satisfactory quality of life than those in the Western medicine-treated group. For the Clodronic acid treatment group, patients generally showed worsened symptoms and quality of life deteriorated. The ECOG index of the BBYNG group was statistically better than that of the Clodronic acid group. Within the 72-week clinical observational period, the mortality of Clodronic acid group is significantly higher that of the BBYNG group. The effects of BBYNG group as presented in relieving the pain-induced influence on patients' emotion, interpersonal relationship and entertainment was more pronounced than that in the Clodronic acid group. / Wu Ka. / 論文(哲學博士)--香港中文大學, 2006. / 參考文獻(p. 299-324). / Adviser: Leung Ping Chung. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1570. / 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 Chinese and English. / School code: 1307. / Lun wen (zhe xue bo shi)--Xianggang Zhong wen da xue, 2006. / Can kao wen xian (p. 299-324). / Wu Ka.
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Estudo de fase II de substituição do 5-FU por capecitabina no esquema de quimio-radioterapia em pacientes com carcinoma de células escamosas do canal anal / Phase II study of capecitabine in substitution of 5-FU in the chemoradiotherapy regimen for patients with squamous cell carcinoma of the anal canal

Oliveira, Suilane Coelho Ribeiro 30 January 2015 (has links)
Introdução: O carcinoma de células escamosas (CEC) do canal anal é uma neoplasia pouco frequente, correspondendo a 1-5% dos tumores intestinais. Entretanto, o risco de CEC do canal anal vem crescendo. O tratamento padrão do CEC de canal anal nos estádios II-III consiste em 5-fluorouracil infusional associado a mitomicina-C e radioterapia, desde 1974. Estudos clínicos com o objetivo de identificar novos esquemas terapêuticos mais convenientes para câncer do canal anal devem continuar. Métodos: Pacientes com CEC de canal anal T2-4N0M0 ou T (qualquer) N1-3M0, com bom performance clínico, função renal e hematológica normais foram tratados com capecitabina 825 mg/m2 12/12 horas durante a radioterapia associada a dose única de mitomicina-C 15 mg/m2 no Dia 1. O objetivo primário do estudo foi determinar a taxa de controle local em 6 meses da associação de capecitabina, mitomicina-C e radioterapia em pacientes com câncer do canal anal. Os objetivos secundários foram determinar a taxa de toxicidade aguda graus 3-4, conforme os critérios da CTCaev4.0, taxa de resposta completa 6 semanas após término da quimio-radioterapia, sobrevida global e livre de progressão e taxa de colostomia em 1 ano. O tamanho da amostra foi calculado usando a ferramenta \"estágio único de Fleming\". Considerando 85% de eventos esperados (taxa de controle local em 6 meses), 1 desvio padrão e 5% de erro alfa, o tamanho ideal da amostra foi de 51 pacientes. Resultados: De novembro/2010 a fevereiro/2014, 51 pacientes foram incluídos, sendo avaliados 43 pacientes. Dezessete pacientes (39,5%) tinham estádio II, 11 (25,6%) estádio IIIA e 15 (34,9%) estádio IIIB. O seguimento mediano foi de 23,1 meses. Entre os pacientes que foram avaliados em 6 meses, 3 (7%) apresentaram resposta clínica parcial, 37 (86%) tiveram resposta clínica completa e 3 (7%) apresentaram progressão de doença. O controle loco-regional em 6 meses foi de 86%. Em relação às toxicidades graus 3-4, observaram-se diarreia grau 3, em 4,6% dos pacientes, radiodermite grau 3, em 23,2%, vômitos grau 3, em 2,3%, plaquetopenia graus 3-4, em 6,9%, leucopenia grau 3, em 6,9%, e linfopenia grau 3, em 11,6%. Um paciente HIV positivo (2,3%) apresentou choque séptico grau 4, pneumonia grau 4, meningoencefalite herpética grau 4 e síndrome de ativação macrofágica grau 4. A taxa de colostomia foi de 18,6%. Conclusão: Capecitabina e mitomicina-C são um tratamento bem tolerado em pacientes com carcinoma de canal anal, com controle loco-regional em 6 meses em 86% dos pacientes. Palavras-chave: carcinoma de células escamosas, câncer anal, capecitabina, radioterapia, mitomicina-c / Background: Squamous cell carcinoma (SCC) of the anal canal is an uncommon malignancy accounting for 1-5% of intestinal tumors; however, its incidence has been increasing. Treatment for stage II and III anal canal SCC is infusional 5-fluorouracil associated with mitomycin and radiotherapy, since 1974. More convenient treatments for patients are needed. Methods: Patients with SCC of anal cancer T2-4N0M0 or T (any) N1-3M0, with good performance status, normal blood, and renal function were treated with capecitabine 825 mg/m2 bid during radiotherapy associated with a single dose of mitomycin 15 mg/m2 on day 1. Primary objective was local control rate at 6 months determined by clinical examination and radiological assessment. Sample size was calculated using Fleming single stage design. Results: From november/2010 to february/2014 51 patients were initially included, however 43 patients were assessed. Seventeen patients (39.5%) were stage II, 11 patients (25.6%) stage IIIA, and 15 patients (34.9%) stage IIIB. Four patients (9.3%) were HIV-positive, while 39 (90.7%) were HIV-negative. Median follow-up was 23.1 months. Among patients who finished the treatment and were reevaluated at 6 months 3 patients (7%) presented partial response, 37 patients (86%) had complete response, and 3 patients developed progression of the disease (7%). Regarding grade 3-4 toxicities, 10 patients (23.2%) had grade 3 radiodermitis, 3 patients (6.9%) had grade 3-4 thrombocytopenia, 5 (11.6%) had grade 3 lymphopenia, 1 patient (2.3%) had grade 3 vomiting, 2 patients (4.6%) had grade 3 diarrhea and 3 patients (6.9%) had grade 3 leukopenia. One HIV+ patient had septic shock, pneumonia, herpetic encephalitis and macrophage activation syndrome. Colostomy rate was 18.6%. Conclusions: Capecitabine and mitomycin with radiotherapy seem to be a safe treatment for SCC of the anal cancer, with a complete response rate in 6 months of 86%

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