Medicine and Health Sciences Commons^™

Photodynamic Therapy Agents: The Power Of Mjöllnir To Eradicate Cancer, Sidney M. Hopper

Honors College Theses

After its discovery back in the 1900s, photosensitizers became a critical study for potential treatments and cures for medical issues, including cancer. It was discovered that porphyrins appeared to target and accumulate in proliferating cells, and to reach the cells, a certain wavelength of light with maximum absorbance associated with the porphyrin was necessary to achieve cell death. Photodynamic therapy involves making use of porphyrins or metalloporphyrins as activators when exposed to such light. When activated, these compounds generate reactive oxygen species (ROS), such as HO- or O2-, which can react with nucleic acids found in DNA and RNA. In …

The Discovery And Characterization Of Novel Potent 5-Substituted 3, 3’, 4’, 7-Tetramethoxyflavonoid Dna Triplex Specific Binding Ligands, Vanessa Marie Rangel

University of the Pacific Theses and Dissertations

Chemotherapy works by killing fast dividing cells. Unfortunately, these drugs are not specific to cancer tissue and can damage normal cells. Chemotherapy is like taking poison and hoping it kills the cancer cells before it kills you. As an alternative, many researchers have investigated the use of antigene therapy to selectively target cancer causing genes to avoid off target effects. Although promising, the theory is limited by the stability of the triplex structure. Here, we report the discovery of potent triplex binding ligands derived from the natural product quercetin. Chemical derivatives of 5-substituted 3, 3’, 4’, 7-tetramethoxyquercetin derivatives were characterized …

Development Of Biomaterials For Drug Delivery, Raquel De Castro

Graduate Theses and Dissertations

Drug delivery systems (DDS) have highly evolved in the last decades with the development of hydrogels and nanoparticles. However, high systemic uptake, side effects, low bioavailability, and encapsulation efficiency continue to be a major hurdle faced by such DDSs.

Nanoparticles and hydrogels can be specifically designed for targeted DDSs to mitigate some of the problems. This dissertation aimed to design two DDSs for ocular drug delivery and one for cancer treatment. The first project sought to develop chitosan nanoparticles (Cs-NP) using PEGDA as a copolymer to encapsulate gentamicin (GtS) for ocular drug delivery. Cs-NPs contain positive charges that can interact …

Biophysical Characterization Of The Par-4 Tumor Suppressor: Evidence Of Structure Outside The Coiled Coil Domain And Interactions With Platinum Chemotherapeutics, Andrea Megan Clark

Chemistry & Biochemistry Theses & Dissertations

Prostate apoptosis response-4 (Par-4) is an apoptosis-inducing tumor suppressor protein. Full-length Par-4 has previously been shown to be a predominantly intrinsically disordered protein (IDP) under neutral conditions, with significant regular secondary structure evident only within the C-terminal coiled coil domain. However, IDPs can gain ordered structure through the process of induced folding, which often occurs under non-neutral conditions. Previous work has shown that the Par-4 leucine zipper, which is a subset of the C-terminal coiled coil domain, is disordered under neutral conditions, but forms a dimeric coiled coil at acidic pH. Increase in ionic strength was also shown to increase …

Design, Synthesis, And Anticancer Properties Of Ru(Ii) Complexes With Organometallic, “Expanded” Bipyridine, And O,O’-Chelating Ligands, Raphael Ryan

Theses and Dissertations--Chemistry

Cancer is a worldwide public health crisis that requires new and improved drugs to be developed to extend survival rates and improve quality of life for the patient. Platinum-based drugs are used in approximately 50% of cancer treatment regimens. These drugs are highly effective in many kinds of cancer; however, cancers can develop platinum resistance and these drugs have troubling side effects that reduced their use and efficacy. To overcome these disadvantages, many other metals have been studied for their anticancer properties. Notably, the anticancer properties of ruthenium-based agents have drawn considerable attention with multiple ruthenium complexes entering clinical trials. …

Mitochondria Imaging And Targeted Cancer Treatment, Tinghan Zhao

Dissertations

Mitochondria are essential organelles as the site of respiration in eukaryotic cells and are involved in many crucial functions in cell life. Dysfunction of mitochondrial metabolism and irregular morphology have been frequently found in human cancers. The capability of imaging mitochondria as well as regulating their microenvironment is important both scientifically and clinically. Mitochondria penetrating peptides (MPPs), certain peptides that are composed of cationic and hydrophobic amino acids, are good candidates for mitochondria targeting. Herein, a novel MPP, D-argine-phenylalanine-D-argine-phenylalanine-D-argine-phenylalanine-NH₂ (rFrFrF), is conjugated with a rhodamine-based fluorescent chromophore (TAMRA). The TAMRA-rFrFrF probe exhibits advantageous properties for long-term mitochondria tracking of …

Synthesis Of New Aliphatic Pseudo-Branched Polyester Co-Polymers For Biomedical Applications, Zachary Shaw

Electronic Theses & Dissertations

In this study, a hyperbranched polyester co-polymer was designed using a proprietary monomer and diethylene glycol or triethylene glycol as monomers. The synthesis was carried out using standard melt polymerization technique and catalyzed by p-Tolulenesulfonic acid. The progress of the reaction was monitored with respect to time and negative pressure, with samples being subjected to standard characterization protocols. The resulting polymers were purified using the solvent precipitation method and characterized using various chromatographic and spectroscopic methods including GPC, MALDI-TOF, and NMR. We have observed polymers with a molecular weight of 29,643 kDa and 33,996 kDa, which is ideal to be …

Caspases And Cancer: Connections Through Circular Dichroism Spectroscopy, Sarah M. Hethcox

Honors College Theses

While excessive cell death inevitably leads to negative effects, the endurance of damaged cells in the presence of death signals can be equally detrimental to health. Apoptosis, or programmed cell death, is a highly regulated process in which cues from within or from outside a cell can trigger an irreversible sequence of signals that carry out cell destruction known as the apoptotic cascade. A group of enzymes called caspases play a vital role in this cascade with some participating as initiators and others acting as effectors of protein cleavage and intracellular breakdown. Although it is normal for the activity of …

Killing Breast Cancer One Porphyrin At A Time, Taylor C. Lymburner

Honors Theses

New treatments for cancer are continuously being developed and improved. One such treatment is Photodynamic Therapy, more commonly referred to as PDT. PDT is quickly becoming more popular due to its relative lack of side effects that are present in other treatments. In PDT, light-sensitive agents are required and are activated by light in the targeted cells. There are many types of PDT agents but the one focused on in this research is a four-pyrrole ring structure known as a porphyrin. The combination of H2 TPPC with 3- amino-oxetane-3-yl-methanol created the final product ofH2TPP-Oxo-MeOH. Once the porphyrin was formed, it …

Treating Breast Cancer With Light: The Creation Of Two Photodynamic Therapy Agents, Victoria Lackey

Honors Theses

Photodynamic therapy (PDT) is a treatment for a wide display of diseases, including cancer, that has become gradually widespread. The procedure requires the usage of photosynthesizing agents, which are activated in the presence of light. One quite successful photodynamic therapy agent is an aromatic structure made up of four pyrrole rings called a porphyrin. This research focused on producing the water-soluble porphyrins, H2TPP-3-PEG-OH and H2TPP-PiperMe-OH, through the attachment of the starting porphyrin, H2TPPC, with 3-polyethyleneglycol and 3-piperidinemethanol, respectively. The novel, water-soluble agent was purified and characterized by infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), and UV-vis spectroscopy. Purity was …

Parp Pet Imaging Agents, Brandon Carney

Dissertations, Theses, and Capstone Projects

The poly (adenosine-diphosphate (ADP) ribose) polymerase (PARP) family of enzymes has been of interest to researchers and clinicians for over fifty years, especially the first member of the family, PARP1. This enzyme has become a target for cancer therapeutics due the reliance of highly proliferating cells on PARP1 for genomic maintenance. In the coming age of individualized medicine, however, highly specific therapeutic agents like PARP inhibitors are in need of similarly highly specific companion diagnostic agents. These kind of agents have been made possible with the quickly progressing field of molecular imaging. Specifically, positron emission tomography (PET) has enabled the …

One-Pot Syntheses And Characterizations Of “Click-Able” Polyester Polymers For Potential Biomedical Applications, James F. Beach Ii

Electronic Theses & Dissertations

In this study, a synthetic polyester polymer was designed using polyethylene glycol, sorbitol, glutaric acid and 4-pentynoic acid as monomers. The synthesis was carried out using standard melt polymerization technique and catalyzed by Novozyme-435, an enzyme suitable for polyesterification of biocompatible compounds. The progress of the reaction was monitored with respect to time and vacuum exposure, with samples being subjected to standard characterization protocols. Polymers with high molecular weight and water solubility were chosen for further modification into folate-functionalized polymeric nanoparticles for targeted drug delivery to cancer cells. This was achieved by employing a solvent diffusion method, wherein the polymer …

Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett

Undergraduate Honors Theses

Pyrrolobenzodiazepines (PBDs) are a group of naturally occurring compounds that were discovered in the cultures of Streptomyces in the 1960s. Some natural PBDs discovered in these cultures, such as anthramycin and sibiromycin, were shown to possess a broad spectrum of anti-tumor activity. Since cancer is still a leading cause of death globally, the development of novel anti-proliferative derivatives of PBDs is essential for human welfare worldwide. Further synthesis and structure-activity relationship (SAR) studies of the parent natural products and their tetracyclic analogs will lead to the discovery of drug candidates. In this work, thirteen PBD analogues were synthesized using no …

Synthesis, Surface Functionalization, And Biological Testing Of Iron Oxide Nanoparticles For Development As A Cancer Therapeutic, Stanley E. Gilliland Iii

Theses and Dissertations

Iron oxide nanoparticles are highly researched for their use in biomedical applications such as drug delivery, diagnosis, and therapy. The inherent biodegradable and biocompatible nanoparticle properties make them highly advantageous in nanomedicine. The magnetic properties of iron oxide nanoparticles make them promising candidates for magnetic fluid hyperthermia applications. Designing an efficient iron oxide nanoparticle for hyperthermia requires synthetic, surface functionalization, stability, and biological investigations. This research focused on the following three areas: optimizing synthesis conditions for maximum radiofrequency induced magnetic hyperthermia, designing a simple and modifiable surface functionalization method for specific or broad biological stability, and in vitro and in …

Synthesis And Characterization Of Imidazolium Salt Derivatives For Anti-Tumor Activity, Ryan W. Pearce

Williams Honors College, Honors Research Projects

Several aldehydes (butanal, pentanal, hexanal, 4-hydroxybenzaldehyde) were reacted with 1,3-bis(naphthalen-2-ylmethyl)-imidazolium bromide (1) to produce novel C² substituted imidazolium salts for the potential use against non-small cell lung cancer in humans. Compounds 2-(1-hydroxypentyl)-1,3-bis(naphthalen-2-ylmethyl)-imidazolium bromide (3) and 2-(1-hydroxyhexyl)-1,3-bis(naphthalen-2-ylmethyl)-imidazolium bromide (5) were successfully synthesized with structures supported by NMR and mass spectrometry. Characterization by ¹H NMR showed evidence of 1 in both compounds. The tumor cell growth inhibition of 3 against non-small cell lung cancer lines NCI-A549, NCI-H460, HCC827, and NCI-H1975 was tested and found to be comparable to cisplatin as measured by MTT assay. …