by Xin-xia Tian. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. 195-212). / 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.

Progression and regression of renal fibrosis is observed in patients with diabetic nephropathy (DN). The underlying pathways, especially those that promote regression of fibrosis, remain poorly understood in part due to the fact that most rodent DN models only mirror the early features of human DN. Another obstacle for optimizing treatment strategies is that albuminuria, the current gold standard biomarker of renal damage in DN, often lacks sensitivity and specificity for identification of those patients with diabetes who are at risk of a rapid decline in renal function. A novel DN model, in which diabetes was induced with streptozotocin in Cyp1a1mRen2 rats and hypertension was generated by inducing renin transgene expression with dietary indole-3-carbinol (I-3-C), mimicked many of the key biochemical, pathological and transcriptomic changes observed in the kidney of patients with DN. Recently, the model was extended to include a ‘reversal phase’ in which glycaemia was tightly controlled and blood pressure normalized for eight weeks after an ‘injury phase’ of 28 weeks. The present study aims to employ this novel rodent model to examine pathways activated in the kidney during and following reversal of hyperglycaemia and hypertension and to identify new biomarkers that might complement albuminuria in assessing risk of renal deterioration in patients with diabetes. Methods Tissue and urinary specimen from the Cyp1a1mRen 2 model of DN were analysed by realtime-PCR, Western-Blot, ELISA and staining techniques including immunohistochemistry, immunofluorescence and zymography. To establish in-situ zymography a model of ureteric obstruction was used. Urinary peptidomic analysis as well as measurement of urinary exosomes and microparticles was performed in the model and in patients with DN utilizing liquid chromatography/tandem mass-spectrometry, nanoparticle tracking analysis (NTA) or flow cytometry. Results Tight control of blood glucose and blood pressure during an 8 week ‘reversal phase’ did not significantly reverse the degree of renal fibrosis accrued during a 28wk ‘injury phase’. However, it did result in a reduction in expression of genes encoding myofibroblast markers and extracellular matrix (ECM) proteins. Genes that were up-regulated during both injury and reversal phases were implicated in adaptive immunity, phagocytosis, lysosomal processing and degradative metalloproteinases (MMPs). Paradoxically MMP activity was massively reduced during both injury and reversal phases. This may be due to an elevated level of tissue inhibitor of metalloproteinase-1 (TIMP-1) protein in both phases. After separating TIMP1 from MMP in renal tissue homogenates from animals of both the injury and reversal phases using gel electrophoresis, MMP activity was restored above that of controls. For biomarker discovery peptidomic analysis was performed on urine from rats at baseline and during the injury and reversal phases of the Cyp1a1mRen2 model of DN and from patients with moderately advanced DN and from normal controls. The use of two different search and analyse tools (Maxquant, Progenesis QI) resulted in the discovery of significantly altered peptides in the urine in rodent and human DN. Further studies focused on peptides derived from those proteins for which the corresponding gene was similarly regulated in the DN model and in human DN. Urinary epidermal growth factor (uEGF) matched these criteria as the reduction of excretion during the injury phase in the DN model was paralleled by reduced EGF protein expression in renal tissue. Key biomarker candidates identified in the first two chapters were measured in urinary specimens of patients from the Edinburgh Type 2 Diabetes study (ET2DS) to test translational utility. MMP7 and other candidates, such as osteopontin or vascular endothelial growth factor (VEGF) were not of value in predicting renal outcomes. Reduced uEGF was significantly associated with increased mortality rate. In a subgroup of 642 study participants who were normoalbuminuric and had a preserved renal function at baseline, a lower uEGF to creatinine ratio was a risk factor for either developing an estimated glomerular filtration rate less than 60 ml/min per 1.73m2, rapid (over 5% per annum) decline in renal function or the combination of both. The latter remained significant after correction for other covariates. Addition of uEGF resulted in a marginal improvement in a model derived from traditional risk factors for predicting rapid decline and the composite end-point. Urinary microparticle (20nm-1000nm) analysis was established in the rodent DN model and translated to patients with DN. Total urinary exosomes (20nm-100nm) or exosomes derived from specific renal cell types including podocytes and tubular cells, increased during the injury phase in the Cyp1a1mRen2 model followed by a decrease after reversal phase. In a pilot study comprising participants with advanced chronic kidney disease, the urinary exosome concentration correlated with renal function. In the ET2DS an increased exosome concentration at baseline indicated a higher risk for renal deterioration during four years follow-up even after correction for baseline eGFR. Urinary microvesicles (100nm-1000nm) concentration increased during the injury phase in the DN model though correlation with renal function in humans was only significant if kidney-specific marker (podocalyxin) positive microvesicles were measured. Conclusion Normalisation of hyperglycaemia and hypertension in the DN model allows the study of genetic and protein regulation during the injury and reversal phases. ECM-production but not ECM-degradation genes are down-regulated during the reversal phase. The lack of reduction in ECM during the reversal phase might be caused by persistently reduced MMP activity due to the presence of TIMP-1. Targeting TIMP might be a treatment strategy to promote reduction of renal fibrosis. For the first time, the analysis of urinary peptidomics was integrated with previous transcriptomic findings in the Cyp1a1mRen2 model and patients with DN for biomarker discovery. The approach was validated using different analysis tools and successfully identified candidate markers which were increased or reduced in DN. Candidates included uEGF, which identified patients with DN who were at risk of a rapid decline of renal function. Though the marker requires further confirmation in other cohorts, it might be especially useful for patients with type 2 diabetes, in whom renal decline is often uncoupled from the development of albuminuria. Finally, the DN model helped to develop the methodology of microparticle analysis. For the first time a potential prognostic value of urinary exosome analysis in patients with diabetes has been demonstrated. Future work will include further optimisation of the methodologies, including labelling of microparticles with multiple antibodies and increasing study participant numbers.

A major pursuit of Developmental Biology is to determine how organisms composed of cells containing a single genome generate stereotyped body plans with diverse, complex morphologies. The development of these patterns is often determined by gradients of secreted factors known as morphogens, which activate cascades of gene expression to subdivide fields of cells into increasingly complex patterns. In many animals, including Drosophila, a rudimentary anterior-posterior (A-P) and dorsal-ventral (D-V) axes of the body plan are already established in the zygote, but the proximal-distal (P-D) axis of any appendages must be generated and patterned seperately. The spatio-temporal information responsible for activating gene expression and cell signalling that establishes this new axis is integrated at DNA regulatory elements often referred to as enhancers. The segmented leg of the insect Drosophila melanogaster offers an ideal system for studying how signalling pathways control P-D axis establishment and patterning. In addition to the fact that flies are a particularly genetically tractable model organism, many of the signals required for leg patterning have already been identified. A number of signalling pathways, including Wingless (Wg), Decapentaplegic (Dpp) and Epidermal Growth Factor Receptor (EGFR), are important for proper P-D axis patterning in a dynamic fashion during embryonic and larval development. The leg primordia are fist specified in the embryo and then patterned throughout development as intercalated circles and rings of gene expression are established in the leg imaginal disc. The radius of these domains corresponds to the P-D axis of the adult appendage. A rudimentary P-D axis is established in the embryo and the larval leg imaginal disc by the expression of the transcription factors Distalless, Dachshund and Homothorax in distal, medial and proximal domains, respectively. The P-D axis is further refined by activation of EGFR signalling in the presumptive tarsus, the distal-most portion of the fly leg, during the early third larval instar. As well as slightly later, in medial and proximal rings. EGFR signalling is a ubiquitous pathway with numerous roles throughout fly development as well as across metazoan taxa. Its activation produces diverse cellular outcomes such as growth, differentiation, or regulation of apoptosis depending on the precise regulation of its inputs and modulation of intracellular signalling components in a tissue-specific manner. The precise mechanism by which EGFR signalling is activated during tarsal patterning is the focus of this dissertation. As a crucial first step in the detailed characterization of EGFR activation in the leg, we have identified leg-specific enhancers of the genes encoding the neuregulin-like EGF ligand Vein and the ligand-activating protease Rhomboid and performed genetic and site-specific mutagenesis experiments to characterize the factors necessary to activate expression of vein and rho in the distal leg. While the enhancers of vein and rho (vnE and rhoE, respectively) employ similar transcriptional programs to activate target gene expression, there are some key differences. Both enhancers require Dll for their expression throughout leg development, however vnE requires Wg and Dpp only early and later becomes independent from these signals while rhoE requires them until much later in development. Further, vnE requires Sp1 while rhoE does not. These differences may be important for the precise timing of expression of these genes, with vn expression coming on several hours earlier than that of rho. It has been proposed that the distal source of EGFR ligand may act as a long-range morphogen to pattern the entire tarsus in a graded manner (Campbell, 2002; Galindo et al., 2005). Our analysis indicates that vnE and rhoE represent the only sources of EGFR ligand in the distal leg. Therefore, in order to determine the importance of distal of EGFR signalling for tarsal patterning we carried out CRISPR targeting to delete vnE and rhoE. Because these deletions produce only mild distal leg truncations and cannot be worsened by removal of other candidate EGFR inputs (for example the Rho homolog, Roughoid) we conclude that the long-range distal gradient model for P-D patterning by EGFR must be revised. Instead we propose that the tarsal segments are patterned by the combined action of a local, distal gradient of EGFR supplied by vnE and rhoE combined with secondary, more medial sources of EGFR signal. Our analysis of the mechanism by which EGFR patterns the distal leg segments improves our understanding not only of leg development, but also of how the EGFR pathway is regulated in general. Our conclusions have important evolutionary implications, as receptor tyrosine kinase signalling, of which EGFR is an example, is involved in limb patterning in taxa whose limbs themselves are not thought to be structurally homologous to fly legs (Panganiban et al., 1997; Pires-daSilva and Sommer, 2003). Further, the components of the EGFR pathway assessed in this work are highly conserved signalling molecules, involved in cell proliferation and are therefore often misregulated in tumors. A nuanced understanding of the ways in which EGFR signalling is activated, particularly via regulation at non-protein-coding loci, could motivate new therapeutic approaches.

Cheung Tsz Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 187-203). / Abstracts in English and Chinese. / Acknowledgements --- p.is / Abbreviations --- p.II / Abstracts --- p.V / List of Figures --- p.IX / List of Tables --- p.XIII / Contents / Chapter Chapter 1. --- General Introduction / Chapter 1.1 --- Cancer --- p.1 / Chapter 1.2 --- Growth Factor --- p.2 / Chapter 1.3 --- Growth Factor and Growth Factor Receptor --- p.4 / Chapter Chapter 2. --- Alteration of EGF Responses and EGFR Signaling in EGF-conditioned A431 cells / Chapter 2.1 --- Background Information / Chapter 2.1.1 --- Epidermal Growth Factor (EGF) --- p.6 / Chapter 2.1.2 --- Epidermal Growth Factor Receptor (EGFR) --- p.10 / Chapter 2.1.2.1 --- The Structure of EGFR --- p.10 / Chapter 2.1.2.2 --- The EGFR Family --- p.11 / Chapter 2.1.2.3 --- EGFR Activation --- p.13 / Chapter 2.1.3 --- The Intracellular Signal Transduction Pathways in EGFR Signaling --- p.18 / Chapter 2.1.3.1 --- The Ras/Raf/MAPK Pathway (MAPK pathway) --- p.19 / Chapter 2.1.3.2 --- The Jak/Stat Pathway --- p.23 / Chapter 2.1.3.3 --- The PI3K/Akt Pathway --- p.28 / Chapter 2.1.4 --- EGFR and Cancer --- p.31 / Chapter 2.1.5 --- EGFR-targeted Cancer Therapy --- p.35 / Chapter 2.1.5.1 --- Monoclonal Antibody (MAb) --- p.36 / Chapter 2.1.5.2 --- Immunotoxin Conjugates --- p.37 / Chapter 2.1.5.3 --- Bispecific Antibody --- p.37 / Chapter 2.1.5.4 --- Small-molecule EGFR Tyrosine Kinase Inhibitor (EGFR-TKI) --- p.38 / Chapter 2.1.5.5 --- Antisense Oligonucleotide --- p.39 / Chapter 2.2 --- Objectives --- p.41 / Chapter 2.3 --- Materials and Methods / Chapter 2.3.1 --- Materials --- p.42 / Chapter 2.3.2 --- Methods / Chapter 2.3.2.1 --- Cell Lines --- p.44 / Chapter 2.3.2.1.1 --- Establishment of Epidermal Growth Factor (EGF)-conditioned A431 Cells (EGF-conditioned Cells) ´ؤ AC Cells --- p.44 / Chapter 2.3.2.2 --- Growth Curve between A431 Parent Cells and EGF-conditioned Cells --- p.45 / Chapter 2.3.2.3 --- Epidermal Growth Factor (EGF) Sensitivity Assay --- p.45 / Chapter 2.3.2.4 --- Western Blot Analysis --- p.47 / Chapter 2.3.2.4.1 --- Protein Samples Preparation --- p.47 / Chapter 2.3.2.4.2 --- Protein Assay (by BCA Protein Assay Reagent) --- p.48 / Chapter 2.3.2.4.3 --- Protein Electrophoresis --- p.49 / Chapter 2.3.2.4.4 --- Electroblot (Protein Transfer) --- p.50 / Chapter 2.3.2.4.5 --- Antibody Probing (Immunoblotting) --- p.51 / Chapter 2.4 --- Results / Chapter 2.4.1 --- Growth Curve --- p.53 / Chapter 2.4.2 --- EGF Responses of A431 Parent Cells and EGF-conditioned Cells by MTT Assay --- p.55 / Chapter 2.4.3 --- The EGFR Expression Levels in A431 Parent Cells and EGF-conditioned Cells by Western Blot Analysis --- p.57 / Chapter 2.4.4 --- EGF-induced Protein Tyrosine Phosphorylation Pattern in A431 Parent Cells and EGF-conditioned Cells by Western Blot Analysis --- p.59 / Chapter 2.4.5 --- The Expression Profiles of EGFR Signaling Molecules in A431 Parent Cells and EGF-conditioned Cells by Western Blot Analysis --- p.61 / Chapter 2.4.5.1 --- The Ras/Raf/MAPK Pathway --- p.62 / Chapter 2.4.5.2 --- The Jak/Stat Pathway --- p.63 / Chapter 2.4.5.3 --- The PI3K/Akt Pathway --- p.64 / Chapter 2.4.6 --- The Cellular Responses to the Modifiers that Targeting the EGFR Signaling --- p.68 / Chapter 2.4.6.1 --- The Sensitivity of A431 Parent Cells and EGF-conditioned Cells to Various Signaling Modifiers --- p.69 / Chapter 2.4.6.2 --- The Influence of EGFR Signaling Modifiers on EGF --- p.76 / Chapter 2.5 --- Discussion --- p.85 / Chapter Chapter 3. --- The Inter-relationship between the Differential Anti-cancer Drugs Sensitivity and Alteration of EGFR Signaling in EGF-conditioned A431 Cells / Chapter 3.1 --- Background Information / Chapter 3.1.1 --- Drug Resistance and its Mechanisms in Tumor Cells --- p.90 / Chapter 3.1.2 --- Anti-cancer Drugs ´ؤ Introduction / Chapter 3.1.2.1 --- Camptothecin (CPT) --- p.93 / Chapter 3.1.2.2 --- Methotrexate (MTX) --- p.95 / Chapter 3.1.2.3 --- 5-fluorouracil (5-Fu) --- p.98 / Chapter 3.1.2.4 --- Vincristine (VCR) and Taxol --- p.104 / Chapter 3.1.2.5 --- Cisplatin (cis-DDP) --- p.108 / Chapter 3.2 --- Objectives --- p.110 / Chapter 3.3. --- Materials and Methods / Chapter 3.3.1 --- Materials --- p.112 / Chapter 3.3.2 --- Methods / Chapter 3.3.2.1 --- Cell Lines --- p.115 / Chapter 3.3.2.2 --- Determination of Drug Sensitivity by MTT Assay --- p.115 / Chapter 3.3.2.2.1 --- Determination the Influence of EGFR Signaling Modifiers on the Differential Anticancer Drugs Sensitivity by MTT Assay --- p.115 / Chapter 3.3.2.3 --- Semi-quantitative RT-PCR --- p.116 / Chapter 3.3.2.3.1 --- Preparation of RNA Samples --- p.116 / Chapter 3.3.2.3.2 --- RT-PCR --- p.117 / Chapter 3.3.2.4 --- DNA Fragmentation Assay --- p.118 / Chapter 3.3.2.5 --- Western Blot Analysis --- p.120 / Chapter 3.3.2.6 --- Northern Blot Analysis --- p.120 / Chapter 3.4 --- Results / Chapter 3.4.1 --- The Responses to Various Anti-cancer Drugs / Agents in A431 Parent Cells and EGF-conditioned Cells --- p.122 / Chapter 3.4.2 --- The Expressions of Classical Cellular Drug Resistant Factors in EGF-conditioning-associated Differential Anti-cancer Drugs Sensitivity --- p.126 / Chapter 3.4.2.1 --- Camptothecin Sensitivity --- p.126 / Chapter 3.4.2.2 --- Methotrexate Sensitivity --- p.130 / Chapter 3.4.2.3 --- 5-fluorouracil Sensitivity --- p.135 / Chapter 3.4.2.4 --- Vincristine and Taxol Sensitivity --- p.141 / Chapter 3.4.3 --- EGFR Signaling Modifiers and Differential Anti-cancer Drugs Sensitivity by MTT Assay --- p.143 / Chapter 3.4.3.1 --- Methotrexate --- p.143 / Chapter 3.4.3.2 --- Vincristine --- p.147 / Chapter 3.4.3.3 --- Taxol --- p.149 / Chapter 3.5 --- Discussion --- p.153 / Chapter Chapter 4. --- Identification of Differentially Expressed Genes in A431 Parent Cells and EGF-conditioned Cells by Differential Display (DD) / Chapter 4.1 --- Introduction 一 Differential Display (DD) --- p.156 / Chapter 4.2 --- Objectives --- p.160 / Chapter 4.3 --- Materials and Methods / Chapter 4.3.1 --- Materials --- p.161 / Chapter 4.3.2 --- Methods / Chapter 4.3.2.1 --- Cell Lines --- p.163 / Chapter 4.3.2.2 --- RT-PCR-based mRNA Differential Display --- p.163 / Chapter 4.3.2.2.1 --- Preparation of RNA Samples --- p.163 / Chapter 4.3.2.2.2 --- Identification of Differentially Expressed Genes by RT-PCR --- p.164 / Chapter 4.3.2.2.3 --- Reamplification of cDNA Probes --- p.164 / Chapter 4.3.2.2.4 --- Subcloning of the Differentially Expressed cDNAs --- p.165 / Chapter 4.3.2.2.4.1 --- Preparation of the Ultra-competent E.coli Cells for Transformation --- p.165 / Chapter 4.3.2.2.4.2 --- Preparation of Cloning Vector --- p.166 / Chapter 4.3.2.2.4.3 --- Transformation --- p.166 / Chapter 4.3.2.2.5 --- Verification of cDNA Differentially Expression by Colony-PCR and Northern Blot Analysis --- p.167 / Chapter 4.3.2.2.5.1 --- Colony-PCR --- p.167 / Chapter 4.3.2.2.5.2 --- Preparation of Cloned Plasmid cDNA and Bacterial Glycerol Stocks --- p.167 / Chapter 4.3.2.2.5.3 --- Preparation of cDNA Probes for Northern Blot Analysis --- p.168 / Chapter 4.3.2.2.5.4 --- Northern Blot Analysis --- p.168 / Chapter 4.3.2.2.6 --- Sequencing of the Desired Cloned cDNA Inserts --- p.170 / Chapter 4.3 --- Results --- p.171 / Chapter 4.4 --- Discussion --- p.180 / Chapter Chapter 5. --- General Conclusion and Future Perspectives / Chapter 5.1 --- General Conclusion --- p.182 / Chapter 5.2 --- Future Perspectives --- p.185 / References --- p.187

by Lai-pang Law. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 148-182). / ABSTRACT / LIST OF ILLUSTRATIONS / LIST OF TABLES / ACKNOWLEDGEMENTS / ABBREVIATIONS / Chapter CHAPTER I --- INTRODUCTION --- p.1 / Chapter CHAPTER II --- LITERATURE REVIEW --- p.4 / Chapter 2.1 --- The uterus and its changes in the normal menstrual cycle / Chapter 2.2 --- Anatomy and physiology of normal myometrium / Chapter 2.3 --- Clinical features and management of uterine leiomyoma / Chapter 2.4 --- Pathology of human uterine leiomyoma / Chapter 2.5 --- The relationship between growth fractions and ER in breast carcinoma / Chapter 2.6 --- Steroid receptors and epidermal growth factor receptor / Chapter 2.6.1 --- Steroid receptors / Chapter 2.6.2 --- Epidermal growth factor receptor / Chapter 2.7 --- "Structures of oestrogen receptor, progesterone receptor, Ki-67 and epidermal growth factor receptor" / Chapter 2.7.1 --- The structure of oestrogen receptor / Chapter 2.7.2 --- The structure of progesterone receptor / Chapter 2.7.3 --- The structure of Ki-67 / Chapter 2.7.4 --- The structure of epidermal growth factor receptor / Chapter 2.8 --- "Antibodies to steroid receptors, monoclonal Ki-67 and epidermal growth factor receptor" / Chapter 2.8.1 --- Steroid receptors / Chapter 2.8.2 --- Monoclonal Ki-67 / Chapter 2.8.3 --- Epidermal growth factor receptor / Chapter 2.9 --- "Functions of steroid receptors, Ki-67 and epidermal growth factor receptor" / Chapter 2.9.1 --- The functions of steroid receptors / Chapter 2.9.2 --- The functions of Ki-67 / Chapter 2.9.3 --- The functions of epidermal growth factor receptor / Chapter 2.10 --- Cell cycle / Chapter 2.11 --- Immunohistochemistry / Chapter 2.11.1 --- Introduction / Chapter 2.11.2 --- Methodology of immunostaining / Chapter 2.11.3 --- Avidin-biotin-peroxidase complex technique / Chapter 2.11.4 --- Chromogens / Chapter 2.11.5 --- Enhancement methods / Chapter 2.11.6 --- Fixation for immunohistochemistry / Chapter CHAPTER III --- MATERIALS AND METHODS --- p.63 / Chapter 3.1 --- Reagents and chemicals / Chapter 3.1.1 --- Primary monoclonal antibodies / Chapter 3.1.2 --- Secondary antibodies / Chapter 3.1.3 --- Avidin-biotin complex / Chapter 3.1.4 --- DAB solution / Chapter 3.1.5 --- Buffers / Chapter 3.1.6 --- Miscellaneous / Chapter 3.2 --- Patients and specimens / Chapter 3.2.1 --- Specimen collection / Chapter 3.2.2 --- Preparation of specimens / Chapter 3.3 --- Immunohistochemical staining / Chapter 3.3.1 --- Slide preparation / Chapter 3.3.2 --- Antigen retrieval / Chapter 3.3.3 --- Procedures of immunohistochemical staining / Chapter 3.3.4 --- Interpretation of immunostaining / Chapter CHAPTER IV --- RESULTS --- p.80 / Chapter 4.1 --- Clinical information / Chapter 4.2 --- Oestrogen receptor / Chapter 4.3 --- Progesterone receptor / Chapter 4.4 --- Epidermal growth factor receptor / Chapter 4.5 --- Ki-67 / Chapter CHAPTER V --- DISCUSSION --- p.120 / Chapter 5.1 --- Methods and interpretation of the results / Chapter 5.1.1 --- The advantages of the immunohistochemical staining technique / Chapter 5.1.2 --- Interpretation and reporting of immunohistochemical results / Chapter 5.1.3 --- Interpretation of the results by semi- quantitative assessment and statistical analysis / Chapter 5.2 --- The status of steroid receptors in uterine leiomyoma / Chapter 5.2.1 --- ER status in uterine leiomyoma and normal myometrium / Chapter 5.2.2 --- PR status in uterine leiomyoma and normal myometrium / Chapter 5.3 --- EGF-R status in uterine leiomyoma / Chapter 5.4 --- Ki-67 status in uterine leiomyoma and normal myometrium / Chapter 5.5 --- "The relationship between steroid receptors, Ki-67, EGF-R and uterine leiomyoma growth" / Chapter 5.6 --- Biological indices in the assessment of tumor / Chapter 5.7 --- Microwave technology in immunohistology for surgical pathology / Chapter CHAPTER VI --- CONCLUSIONS --- p.144 / REFERENCES --- p.148

Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisors: Dionisios G. Vlachos and Jeremy S. Edwards, Dept. of Chemical Engineering. Includes bibliographical references.

The receptor activator of nuclear factor-kB (RANK) and its ligand, RANKL has have been implicated as an important link between breast cancer and metastasis to bone because of their ability to activate intracellular signal cascades leading to altered cancer cell behaviour and bone breakdown. The JAK/STAT5a cell signaling pathway is also crucial to breast biology and is involved in transcriptional regulation of many genes. The objective of this study is to determine if RANKL mRNA expression is regulated through the JAK/STAT5a pathway by stimulating human breast cancer cell lines, MCF-7 and MDA-MB-231, with prolactin (PRL), epidermal growth factor (EGF) and heregulin-beta1 (HRG-1), all known to activate STAT5a and play a role in breast cancer progression. This study shows that RANKL expression is upregulated by PRL, EGF and HRG-1, and that PRL and HRG-1 regulate transcription through the JAK/STAT5a pathway. / UOIT

No description available.

Thesis (Ph. D.) in Biochemistry and Molecular Biology--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 143-156).

published_or_final_version / Pathology / Master / Master of Philosophy