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The field of cancer therapeutic development has been dominated by two research and discovery paradigms, the cytotoxicity-based or phenotype driven strategy and the target-based rational approach. This thesis describes the standardization of novel assays used in both approaches and the discoveries made using these processes. Rational drug design or the target-based approach to discovering novel anti-cancer agents requires a basic understanding of the oncogenic signals that induce uncontrolled cellular proliferation. c-MET is a proto-oncogene, linked to a number of different cancers, that encodes a receptor tyrosine kinase. As an oncogene, c-MET has been shown to transform cells in the laboratory setting and is dysregulated in number of malignancies. Thus, we sought to discover a small molecule inhibitor of c-MET kinase activity by screening a novel library of small molecules. In the second part of this dissertation, we describe the standardization of a high-throughput assay to identify putative c-MET inhibitors and the results of our screening attempt. Cytotoxicity-based screening is another validated approach that is used to discover anti-cancer agents. As a parallel program to our c-MET discovery effort, we designed a high-throughput cytotoxicity assay to identify a novel small molecule with high cytotoxic activity towards tumor cells. The result of this screen was the identification of ON015640, a novel anti-cancer therapeutic with tubulin-depolymerizing activity. Throughout the course of this project, we tried to discern the advantages and disadvantages of the two predominant paradigms in cancer therapeutic research. Both strategies require careful assay design and an acute understanding of the molecular and genetic underpinnings of cancer. While it is clear that structure-based rational drug design has its merits and its success stories, it has become increasingly clear that seeking out a desired biological effect may serve as a more effective staring point when dealing with cancers for which no clear oncogene addiction phenotype has been observed. / Molecular and Cellular Physiology

Yes / There are hundreds of ligands which can interact with G-quadruplex DNA, yet very few which target i-motif. To appreciate an understanding between the dynamics between these structures and how they can be affected by intervention with small molecule ligands, more i-motif binding compounds are required. Herein we describe how the drug mitoxantrone can bind, induce folding of and stabilise i-motif forming DNA sequences, even at physiological pH. Additionally, mitoxantrone was found to bind i-motif forming sequences preferentially over double helical DNA. We also describe the stabilisation properties of analogues of mitoxantrone. This offers a new family of ligands with potential for use in experiments into the structure and function of i-motif forming DNA sequences.

Despite recent advancements in cancer treatment, the management of heterogeneous cancers poses a persistent challenge. This is best exemplified by the limited success in treating acute myeloid leukemia (AML), which still exhibits a 5-year survival rate of less than 30% to date. The resistance to treatment and high likelihood of relapse in AML patients is believed to be attributed to the elusive nature of cancer stem cells (CSCs). CSCs are characterized by their self-renewal capabilities and blockade to normal differentiation into mature hematopoietic cells, however they are only functionally defined through their engraftment potential upon transplantation into immunodeficient mice to phenocopy human tumorigenesis. Therefore isolation, study and treatment of CSCs is a prominent challenge in cancer research. To circumvent this challenge, our research group has developed a proprietary screening platform capable of identifying compounds within vast chemical space that selectively target surrogate human CSCs while preserving healthy stem cell counterparts. Our approach of screening and identifying compounds that selectively target human CSCs compared to normal SCs focuses on custom compound libraries curated through pre-screening for anti-proliferative and lethality properties in Escherichia coli (E. coli). From a pool of 21,000 active molecules selected from several libraries chemical space totalling 8.7 million compounds, we identified 15 distinct structural frameworks or "scaffolds", each representing different chemical structures that form the basis for potential drug development. Through secondary assays using primary AML patient derived cells, we have prioritized a novel compound, termed MLMB-2231 as a promising lead anti-CSC candidate. However, beyond MLMB-2231's demonstrated ability to selectively target human CSCs over normal stem cells, the cellular and molecular mechanisms of activity are unknown, limiting improvements and use towards investigational new drug application (IND) initiation. Here, I have utilized a variety of chemical genomics techniques to probe the downstream effects and gene targets of MLMB-2231. Apoptosis and cell cycling assays demonstrated that MLMB-2231 operates through an induction of apoptosis at 48h resulting in a G0/G1 cell cycle stall. The use of genome-wide CRISPR viability screening combined with transcriptomic analysis through RNA sequencing identified significant upregulation of pathways associated with aberrant ubiquitin- protease system (UPS), disruption of cell cycling, and upregulation of apoptotic pathways. These findings suggest that MLMB-2231 exerts its effects by interfering with the UPS, leading to impaired protein degradation and cellular stress, disrupting key cell cycle checkpoints, and inducing apoptosis. Future studies will focus on hit validation to confirm direct binding targets and incorporate animal models to evaluate pharmacokinetics (pK) and overall efficacy in vivo, paving the way for potential clinical applications. / Thesis / Master of Science (MSc)

Thesis (LL.M.). / Written for the Institute of Comparative Law. Title from title page of PDF (viewed 2008/01/14). Includes bibliographical references.

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Destination USA examines the works of the travel writer William Least Heat-Moon and his place ·in the tradition of American travel writing. The study begins with an overview of the current scholarship and trends within contemporary American travel writing and then moves on to limit and to define its scope. Next an outline and an in-depth explanation of the structure and thematics of such works is presented. Contemporary American travel writing has two dominant structures: the on-the~road motif and the intimate journey Of~ place. Woven into these two structures are three main themes common to both. The first theme focuses on the role of selfdiscovery in travel writing. The second theme highlights the role of travel writing in discovering hidden or marginalised American voices. The third theme centres around travel writing's use as a warning about or an assessment of the current American situation. Next a historical overview of the roots of American travel writing is undertaken which highlights the role it has played in the foundation of the country as well as providing the basis for those structures and themes outlined above. From there the dissertation moves onto an analysis of the works of William Least Heat-Moon: Blue Highways (1982), PrairyErth (1991) and River-Horse (1999). Heat-Moan's works provide an effective focal point for the understanding of contemporary American travel writing as a whole. They are forward looking and experimental while retaining a continuity with the tradition of American travel writing. An in-depth analysis of his trilogy on the American landscape is supported by previously unpublished interviews by the author. His works are then examined to uncover how they point to travel writing's elision with naturalist prose and work together to form a multifaceted vision of America. !

Most of the service discovery protocols available on the Internet are built upon its logical structure. This phenomenon can be observed frequently from the way in which they behave. For instance, Jini and SLP service providers announce their presence by multicasting service advertisements, an approach that is neither intended to scale nor capable of scaling to the size of the Internet. With mobile and wireless devices becoming increasingly popular, there appears to be a need for performing service discovery in a wide-area context, as there is very little direct correlation between the Internet topology and geographic locations. Even for desktop computers, such a need can arise from time to time. This problem suggests the necessity for an architecture that allows users to locate resources on the Internet using geographic criteria. This thesis presents an architecture that can be deployed with minimal effort in the existing network infrastructure. The geographic information can be shared among multiple applications in a fashion similar to the way DNS is shared throughout the Internet. The design and implementation of the architecture are discussed in detail, and three case studies are used to illustrate how the architecture can be employed by various applications to satisfy dramatically different needs of end-users.