According to the results, Pa-PDT showed inhibitory effect on MDA-MB-231 cells in vitro with an IC50 value of 0.5 muM at 24 h. Pa-PDT was demonstrated to activate intracellular mitogen activated protein kinases (MAPK) pathways via reactive oxygen species (ROS) production. Pa-PDT IS also believed to induce extracellular signal-regulated kinase (ERK)-mediated autophagy and endoplasmic reticulum stress. Pa-PDT in combination with Tamoxifen is demonstrated to exert a synergetic effect in inhibiting cancer growth. The combination treatment induces both intrinsic and extrinsic apoptosis. Regarding the direct cancer cell killing activity, two dimensional gel electrophoresis screening revealed that Pa-PDT regulates proteins which involve in human leukocyte antigen (HLA) class I-restricted antigen-processing machinery. This activation of antigen presentation was confirmed by Western blot analysis and immunostaining. Furthermore, a cross-presentation of antigen with HLA class I proteins and 70-kDa heat shock protein was found in Pa-PDT-treated cells, as shown by the fluorescent microscopic observation and immunoprecipitation assay. Moreover, the immunogenicity of breast cancer cells was increased by Pa-PDT treatment that triggered phagocytic activity by human macrophages. Our findings provide the first evidence that Pa-PDT can trigger both apoptosis and anti-tumour immunity. / Cancer is one of the most lethal diseases worldwide. Treatments of cancer comprise surgical intervention, radiotherapy or chemotherapy; however, their side effects are still need to be overcome. In order to search for anti-cancer treatments with milder side effects and higher efficiency, traditional Chinese medicine (TCM) has been investigated. Previous study in our laboratory reported that pheophorbide a (Pa), an active compound purified from Scutellaria barbata, combined with photodynamic therapy (PDT) approach produces anti-tumour effect in a wide range of human cancers. Because of the lack of protocols for curing late phase breast cancer, my project is to investigate the therapeutic potential of Pa-PDT and its action mechanism on human breast cancer. A human breast cancer cell line MDA-MB-231, which is estrogen receptor nude and resistant to a conventional breast cancer drug tamoxifen, was used as an in vitro tumour model in my study to mimic the late stage of breast cancer. / Pheophorbide a (Pa) has been proposed to be a potential photosensitizer for the photodynamic therapy of human cancer. However, the immunomodulatory effect of Pa, in the absence of irradiation, has not yet been investigated. The present study revealed that Pa possessed immunostimulating effect on a murine macrophages cell line RAW 264.7. Pa could stimulate the growth of RAW 264.7 cells with the maximal effect at 0.5 muM after 48 h of treatment, where MAPK family including c-Jun N-tenninal kinase (JNK), ERK and p38 MAPK were activated by Pa treatment in a dose-dependent manner. Moreover, the induction of interleukin-6 and tumour necrosis factor-a secretion, and the enhancement of phagocytic activity were observed in Pa-treated RAW 264.7 cells. The results were similar in Pa-treated human immune competent cells (e.g. CD4+ and CD14+ cells) at higher Pa concentrations (from 1 to 10 muM). The present work is the first report to demonstrate the potential immunomodulatory effects of Pa on immune competent cells, apart from its well-known anti-tumour activity. / Bui Xuan, Ngoc Ha. / "December 2010." / Advisers: Fung Kwok Pui; Wong Chun Kwok. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 123-144). / 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.

Hoi, Wan Heng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 212-245). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Photodynamic therapy (PDT) is a multimodality cancer treatment available for the palliation or eradication of systemic and cutaneous malignancies. In this thesis, the application of PDT is for the treatment of non-melanoma skin cancer (NMSC). While PDT has a well-documented track record, there are, at this time no significant indicators to suggest the superiority of one treatment regime over the next. The motivation for this work is to provide additional evidence pertaining to PDT treatment variables, and to assist in optimising PDT treatment regimes. One such variable is the treatment light dose. Determining the light dose more accurately would assist in optimising treatment schedules. Furthermore, choice of photosensitiser pro-drug type and application times still lack an evidence base. To address issues concerning treatment parameters, fluorescence spectroscopy – a valuable optical diagnostic technique – was used. Monitoring the in vivo PpIX fluorescence and photobleaching during PDT was employed to provide information pertaining to the progression of treatment. This was demonstrated by performing a clinical study at the Photobiology Unit, Ninewells Hospital and Medical School, Dundee. Two different photosensitiser pro-drugs – either 5-aminolaevulinic acid (ALA) or its methyl ester (MAL) – were investigated and based on the fluorescence and pain data recorded both may be equally suitable for topical PDT. During PDT, surface fluorescence is observed to diminish with time – due to photobleaching – although cancerous cells may continue to be destroyed deep down in the tissue. Therefore, it is difficult to ascertain what is happening at depth in the tumour. This raised the questions; How long after surface PpIX fluorescence has diminished is the PDT treatment still effective and to what depths below the surface is effective treatment provided? In order to address these important questions, a three-dimensional (3D) Monte Carlo radiation transfer (MCRT) model was used to compute the light dose and the ¹O₂ production within a tumour, and the PpIX fluorescence emission from the tumour. An implicit dosimetry approach based on a single parameter – fluorescence photobleaching – was used in order to determine the ¹O₂ generation, which is assumed to be related to tissue damage. Findings from our model recommended administering a larger treatment light dose, advocating an increase in the treatment time after surface PpIX fluorescence has diminished. This increase may ultimately assist in optimising PDT treatment regimes, particularly at depth within tumours.

Chan, Man Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 111-126). / Abstract also in Chinese. / Examination Committee List --- p.ii / Declaration --- p.iii / Acknowledgements --- p.iv / 摘要（Abstract in Chinese) --- p.vi / Abstract --- p.viii / List of Abbreviations --- p.x / List of Figures and Tables --- p.xii / Table of Content --- p.xiv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background of photodynamic therapy (PDT) --- p.2 / Chapter 1.1.1 --- History of PDT --- p.2 / Chapter 1.1.2 --- Photochemistry --- p.3 / Chapter 1.1.3 --- Principal stages of PDT --- p.5 / Chapter 1.1.4 --- Light sources of PDT --- p.6 / Chapter 1.2 --- Anti-tumor effect of PDT --- p.8 / Chapter 1.2.1 --- Mode of cell death --- p.8 / Chapter 1.2.2 --- PDT-induced anti-tumor immunity --- p.9 / Chapter 1.3 --- Clinical applications of PDT --- p.11 / Chapter 1.3.1 --- Photofrin® --- p.11 / Chapter 1.3.2 --- Clinical applications of PDT --- p.13 / Chapter 1.3.3 --- Challenges of PDT for clinical applications --- p.15 / Chapter 1.4 --- The development of new photosensitizers --- p.16 / Chapter 1.4.1 --- Targeted PDT --- p.16 / Chapter 1.4.2 --- Phthalocyanine --- p.18 / Chapter 1.5 --- Objective of my study --- p.21 / Chapter Chapter 2 --- Materials and Methods --- p.23 / Chapter 2.1 --- Synthesis of glucosylated silicon(IV) phthalocyanine (SiPcGlu) --- p.24 / Chapter 2.2 --- In vitro studies --- p.24 / Chapter 2.2.1 --- Cell line and culture conditions --- p.24 / Chapter 2.2.2 --- Photodynamic treatment --- p.25 / Chapter 2.2.3 --- Cell viability assay --- p.27 / Chapter 2.2.4 --- Light dose effect on the photocytotoxicity of SiPcGlu-PDT --- p.27 / Chapter 2.2.5 --- Determination of reactive oxygen species (ROS) production by SiPcGlu-PDT --- p.29 / Chapter 2.2.6 --- Effect of antioxidants on the photocytotoxicity of SiPcGlu-PDT --- p.29 / Chapter 2.2.7 --- Determination of ROS production after SiPcGlu-PDT --- p.30 / Chapter 2.2.8 --- Glucose competitive assay --- p.30 / Chapter 2.2.9 --- Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay --- p.30 / Chapter 2.2.10 --- DNA fragmentation analysis by gel electrophoresis --- p.31 / Chapter 2.2.11 --- Annexin-V & propidium iodide staining assay --- p.32 / Chapter 2.2.12 --- Subcellular localization studies --- p.33 / Chapter 2.2.13 --- Detection of mitochondrial superoxide production --- p.34 / Chapter 2.2.14 --- Assessment of mitochondrial membrane potential --- p.34 / Chapter 2.2.15 --- Caspase-3 activity assay --- p.35 / Chapter 2.2.16 --- "Western blot analyses for cytochrome c, caspase-3, PARP and glucose-regulated protein 78 (GRP78)" --- p.36 / Chapter 2.2.17 --- Ca2+ release from endoplasmic reticulum (ER) --- p.37 / Chapter 2.3 --- In vivo studies --- p.37 / Chapter 2.3.1 --- HT29 tumor-bearing nude mice model --- p.37 / Chapter 2.3.2 --- In vivo photodynamic treatment --- p.39 / Chapter 2.3.3 --- Biodistribution of SiPcGlu --- p.39 / Chapter 2.3.4 --- Assay for plasma enzyme activities --- p.40 / Chapter 2.4 --- Statistical analysis --- p.41 / Chapter Chapter 3 --- Results --- p.42 / Chapter 3.1 --- In vitro studies --- p.43 / Chapter 3.1.1 --- SiPcGlu-PDT induced cytotoxicity on HT29 cells --- p.43 / Chapter 3.1.2 --- Light dose effect on cytotoxicity by SiPcGlu-PDT --- p.46 / Chapter 3.1.3 --- SiPcGlu-PDT induced ROS production --- p.48 / Chapter 3.1.4 --- SiPcGlu-PDT induced cell death through Type I and II photoreactions --- p.48 / Chapter 3.1.5 --- ROS production after SiPcGlu-PDT --- p.51 / Chapter 3.1.6 --- Glucose competitive Assay --- p.55 / Chapter 3.1.7 --- SiPcGlu-PDT induced apoptosis in HT29 cells --- p.57 / Chapter 3.1.8 --- Subcellular localization of SiPcGlu --- p.61 / Chapter 3.1.9 --- SiPcGlu-PDT induced mitochondrial changes --- p.66 / Chapter 3.1.10 --- SiPcGlu-PDT induced caspase activation --- p.68 / Chapter 3.1.11 --- SiPcGlu-PDT increased expression of ER chaperone GRP78 --- p.72 / Chapter 3.1.12 --- SiPcGlu-PDT induced release of Ca2+ from ER --- p.72 / Chapter 3.2 --- In vivo studies --- p.75 / Chapter 3.2.1 --- In vivo photodynamic activities --- p.75 / Chapter 3.2.2 --- Tissue distribution of SiPcGlu --- p.77 / Chapter 3.2.3 --- Analysis of intrinsic toxicity --- p.77 / Chapter Chapter 4 --- Discussion --- p.80 / Chapter 4.1 --- Physical Properties of SiPcGlu --- p.81 / Chapter 4.2 --- In vitro studies --- p.82 / Chapter 4.2.1 --- SiPcGlu-PDT exhibits a high potency in killing HT29 cells --- p.82 / Chapter 4.2.2 --- ROS production is responsible for the cytotoxic effect of SiPcGlu-PDT --- p.83 / Chapter 4.2.3 --- SiPcGlu-PDT induced apoptosis in HT29 cells --- p.85 / Chapter 4.2.4 --- SiPcGlu is localized in various membranous organelles --- p.87 / Chapter 4.2.5 --- SiPcGlu-PDT induced mitochondria-mediated apoptosis --- p.89 / Chapter 4.2.6 --- SiPcGlu-PDT induced ER stress --- p.93 / Chapter 4.3 --- In vivo studies --- p.96 / Chapter 4.3.1 --- SiPcGlu failed to target to tumor tissues --- p.96 / Chapter 4.3.2 --- SiPcGlu-PDT induced retardation in tumor growth --- p.99 / Chapter 4.3.3 --- SiPcGlu is a safe photosensitizer for PDT --- p.101 / Chapter Chapter 5 --- Conclusion and Future Perspectives --- p.103 / Chapter 5.1 --- Conclusion --- p.104 / Chapter 5.2 --- Future Perspectives --- p.106 / Chapter 5.2.1 --- In vitro studies --- p.106 / Chapter 5.2.1.1 --- Lysosomal pathway to cell death --- p.106 / Chapter 5.2.2 --- In vivo studies --- p.107 / Chapter 5.2.2.1 --- Pharmacokinetic studies --- p.107 / Chapter 5.2.2.2 --- Eradication of HT29 tumor by repeated dose of SiPcGlu --- p.108 / Chapter 5.2.2.3 --- SiPcGlu-PDT-induced anti-tumor immunity --- p.108 / Chapter 5.2.2.4 --- Enhancement of tumor selectivity by conjugating with biomolecules --- p.109 / References --- p.110