Medicine and Health Sciences Commons^™

Exploiting Vulnerabilities In The Ras-Rac Signaling Pathway For The Selective Targeting Of Pancreatic Cancer Cells, Neha Chaudhary

Theses & Dissertations

Deregulation of the KRas (Kirsten rat sarcoma virus) GTPase is one of the early hallmarks of Pancreatic Cancer (PC). The most common genetic alteration found in PC are mutations in the KRas protein that block its ability to hydrolyze GTP to GDP and resulting in higher levels of GTP-bound KRas, its active form. Pancreatic tumors driven by oncogenic mutants of KRas tend to be addicted to the oncogene, to the extent that its repression leads to the induction of cell death. This addiction to the KRAS oncogene makes the KRas protein an ideal target for cancer therapy. However, the globular …

Design And Synthesis Of Small Molecule Drugs For Cns Disorders, Kirsten T. Tolentino

Theses & Dissertations

Dopamine (DA) is an important neurotransmitter for the regulation and long-term function of the central nervous system (CNS). DA binds to Dopamine Receptors (DR) to stimulate or inhibit adenyl cyclase production to further elicit a pharmacological response. DRs were cloned, and it was determined that there are two families separated by their function and five total subtypes distinguished by their amino acid structure. The Dopamine 4 receptor (D4R) is the second least studied subtype but has high expression in the frontal cortex, amygdala, hippocampus, hypothalamus, globus pallidus, substantia nigra pars reticula, and thalamus. Dopamine signaling and transmission, especially in the …

Polymeric Chloroquine In Metastatic Pancreatic Cancer Therapy, Rubayat Islam Khan

Theses & Dissertations

Hydroxychloroquine (HCQ) is an established drug that has been used for the treatment of multiple diseases, including malaria, rheumatoid arthritis, and lupus erythematosus. Several recently published studies have highlighted its beneficial use in various types of cancers, and a plethora of clinical trials are currently evaluating its use in cancer therapies, wherein some of the results look promising. The preclinical studies to date suggest HCQ can work effectively in conjunction with traditional cancer treatments, as it has been shown to sensitize tumor cells to a wide range of chemotherapeutic agents. Polymeric HCQ (PCQ), a macromolecular multivalent version of HCQ, has …

Characterization Of 1,1-Diarylethylene Foxm1 Inhibitors Against High-Grade Serous Ovarian Carcinoma Cells, Cassie Liu

Theses & Dissertations

Forkhead box M1 (FOXM1) is a member of the conserved forkhead box (FOX) transcription factor family. Over the last two decades, FOXM1 has emerged as a multifunctional oncoprotein and a robust biomarker of poor prognosis in many human malignancies. FOXM1 and its associated oncogenic transcriptional signature are enriched in >85% of ovarian cancer cases, and FOXM1 expression and activity can be enhanced by a plethora of genomic, transcriptional, post-transcriptional, and post-translational mechanisms. As a master transcriptional regulator, FOXM1 promotes critical oncogenic phenotypes in ovarian cancer, including: (1) cell proliferation, (2) invasion and metastasis, (3) chemotherapy resistance, (4) cancer stem cell …

The Development Of Polymeric Dexamethasone Prodrug Nanomedicines For The Treatment Of Lupus Nephritis, Zhifeng Zhao

Theses & Dissertations

Lupus nephritis (LN) is a significant cause of morbidity and mortality among lupus patients. Glucocorticoids (GCs) are uniformly used in clinical LN management. Their notorious toxicities, however, have hampered the long-term clinical application. To circumvent GCs’ adverse effects while maintaining their potent therapeutic efficacy, we have developed a micelle-forming polyethylene glycol (PEG)-conjugated dexamethasone prodrug (ZSJ-0228), which could passively target the inflamed kidney in NZB/W F1 lupus-prone mice. It was found that monthly ZSJ-0228 treatment for five months significantly reduced the incidence of nephritis in NZB/W F1 mice with an improved survival rate. Unlike the dose equivalent daily dexamethasone treatment, long-term …

Design And Synthesis Of Small Molecular Probes For Cns And Kidney Disorders, Swagat H. Sharma

Theses & Dissertations

The G protein regulated inwardly rectifying potassium channels (GIRK) are a family of inwardly rectifying potassium channels and are key effectors in signaling pathways. GIRK 1/2 channel subunit, predominantly found in the brain, is involved pathophysiology of various neurological disorders including, but not limited to, epilepsy, anxiety, Parkinson's, pain, reward, and addiction. Previously, our laboratory had identified a series of urea containing molecules as GIRK1/2 preferring activators. Unfortunately, the urea series suffers from significant PK liabilities (solubility, brain penetration and high clearance). The chapter 1 of the dissertation describes our efforts in developing three new series of activators with improved …

Development Of Once-A-Year Injectable Formulation Of Cabotegravir For Prevention And Treatment Of Hiv Infection, Tanmay Abhay Kulkarni

Theses & Dissertations

Long-acting cabotegravir (CAB) extends antiretroviral drug (ARV) dosing to monthly for maintenance of human immunodeficiency virus type one (HIV-1) suppression and to every other month for prevention of viral transmission. However, injection dose volumes, site reactions, and clinical oversights that are required remain obstacles towards broad usage. To meet these needs, surfactant coated hydrophobic and lipophilic CAB prodrugs were created with controlled prodrug dissolution, hydrolysis and drug tissue penetration. To such ends, fatty acid ester CAB nanocrystal prodrugs with 14, 18, and 22 added carbon chains were synthesized then nanoformulated as NMCAB, NM2CAB, and NM3CAB. These nanocrystal formulations were tested …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

Characterization Of Di-Aryl Urea Compounds Against Acute And Chronic Toxoplasma Gondii, Austin Sanford

Theses & Dissertations

Toxoplasma gondii is an obligate intracellular parasite that has infected nearly 60 million individuals in the United States alone. Acute infection causes ill effects to the fetus in utero when mothers are primarily infected, and to immunocompromised individuals. Chronic infection consists of quiescent tissue cysts located primarily in brain tissue and is capable of reverting back to the acute stage causing severe toxoplasma encephalitis in immunocompromised individuals. Current treatments for acute infection are lacking while there are no approved treatments for the clearance of chronic infection. The aim of this research was to evaluate a family of di-aryl urea compounds …

Development Of Long-Acting Antiviral Drug Nanoformulations, Denise Cobb

Theses & Dissertations

Antiretroviral therapy (ART) has improved the quality and duration of life for people living with human immunodeficiency virus (HIV) infection. However, opportunities to improve its profile abound. ART is limited by putative viral reservoir penetrance, emergence of viral mutations, inherent toxicities, and regimen non-adherence. These highlight the need improved drug delivery schemes. Previously, our lab has demonstrated that targeting mononuclear phagocytes for antiretroviral drug delivery extends drug half-life and improves penetrance into viral reservoirs, addressing these limitations of ART. Herein, we developed synthetic and biologic antiretroviral (ARV) drug nanocarriers improve the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of ARVs through …

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …

Development Of Hyaluronic Acid-Derived Macromolecular Agents For Multimodal Imaging Probes And Nanomedicine, William M. Payne

Theses & Dissertations

Cancer, one of the most challenging maladies facing modern medicine, is a complex family of diseases that requires a multifaceted treatment regime. In recent years, increased research effort has been placed on the development of nanoscale formulations as a potential method to improve therapeutic efficacy and offer better treatment. Both drug formulation and biomedical imaging has benefitted from the development of new, nanoscale agents. Hyaluronic Acid (HA), a naturally occurring glycosaminoglycan, is a promising platform for the development of new drug delivery systems. Furthermore, hyaluronic acid is the principal ligand for the cell surface receptor CD44, which is overexpressed on …

Theranostics For Antiretroviral Biodistribution And Pharmacokinetics, Brendan M. Ottemann

Theses & Dissertations

RATIONALE: Our laboratories birthed the field of human immunodeficiency virus (HIV) theranostics. The new field allows simultaneous detection (diagnostics) and treatment (therapeutic) for the identification, treatment and inevitable elimination of virus in cell and tissue compartments. By employing theranostics, antiretroviral drugs (ARVs) can be tracked in lymph nodes, gut, spleen and liver. Cellular viral reservoirs including CD4+ T cell populations and mononuclear phagocytes (MP; monocytes, macrophages, microglia and dendritic cells) along with subcellular endosomal structures can now be targeted for drug delivery bringing therapeutics to areas where virus replicates. The overarching idea rests in improving precision targeted ARV delivery. …

Engineering Hyaluronic Acid For Biomedical Applications, Deep S. Bhattacharya

Theses & Dissertations

This work presents research using the naturally available non- sulfated carbohydrate glycosaminoglycan hyaluronic acid (HA) for the synthesis of different chemical derivatives of HA for evaluation of binding kinetics with CD44 and P- selectin proteins for applications in fluorescence image-guided surgery. Chemical derivatives of HA such as deacetylated HA (deHA), sulfated HA (sHA), and deacetylated and sulfated HA (s-deHA) were synthesized by modulating sulfating and deacetylating reagents to alter binding specificities to CD44. Modified HA derivatives and CD44 biophysical interactions were assessed by fluorescence polarization. In silico techniques were also used to determine binding using molecular docking and MM-PBSA approaches. …

Synthesis And Characterization Of Long Acting Darunavir Prodrugs, Mary Banoub

Theses & Dissertations

Patient adherence is critical for ART success to ensure adequate viral suppression, therefore, long-acting antiretrovirals are soon replacing current daily regimens. In recent years, two drugs were successfully transformed into long-acting injectables; CAB LA and RPV LA. These long-acting nanoformulations made it possible to abandon the daily pill burden, instead approximately a bimonthly injection of both drugs is enough to suppress and maintain viral load suppression. Our laboratory has been instrumental in transforming FDA-approved and experimental-HIV medications into long-acting slow effective release drugs, also known as LASER ART. LASER ART consists of slow drug metabolism and high permeability and retention …

Targeted Inhibition Of Histone Deacetyltransferases For Pancreatic Cancer Therapy, Richard Laschanzky

Theses & Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease with a dismal five-year survival rate of less than 10%. One major obstacle in PDAC treatment is acquired drug resistance. Pan-histone deacetylase inhibitors (pan-HDACi) are a relatively new class of anti-cancer drugs, with demonstrated ability to overcome drug resistance and re-sensitize PDAC tumors to Gemcitabine (Gem). These agents target HDACs, a family of 18 enzymes (divided into four classes, I-IV) that catalyze the deacetylation of histones and other cellular proteins and have multiple effects on cell growth, differentiation, survival, and tumorigenesis. Although pan-HDACi have shown significant efficacy in preclinical analysis, and some …

Macromolecular Prodrug For The Treatment Of Ulcerative Colitis, Yuanyuan Sun

Theses & Dissertations

Ulcerative colitis is a chronic inflammatory bowel disease affecting the colon. More than 1 million Americans are affected, with the annual economic burden up to 14.9 billion in the United States. By far, ulcerative colitis still lacks the cure and the current treatment strategies are limited due to severe side effects and in-sufficient efficacy. The tofacitinib (Xeljanz) is the only approved oral medication by for adults with moderately-to-severely-active ulcerative colitis. But the related side effects and serious infections still have to be resolved. In the previous study in our lab, the researchers have successfully developed and characterized multiple hy-drophilic prodrug …

Development Of Approaches Of Tumor Trapping Enhanced Bb2r-Targeted Radiopharmaceuticals For Prostate Cancer, Wenting Zhang

Theses & Dissertations

The Gastrin-Releasing Peptide Receptor (BB2r) has been intensively investigated as a cancer target over the years. Numerous diagnostic and therapeutic BB2r-targeted agents have been developed for various solid tumors, including prostate cancers, due to the high expression level of BB2r on neoplastic relative to normal tissues. The development of those targeted agents have mainly utilized the modified c-terminal of bombesin(BBN), a peptide that has nanomolar binding affinity to human BB2r. However, a major issue that hinders the clinical translational potential of low-molecular weight, receptor-targted agents, is their short residence time at tumor tissues due to the intrinsically high diffusion and …

Development Of A Long-Acting Nanoformulation Of Dolutegravir For Prevention And Treatment Of Hiv-1 Infection, Brady Sillman

Theses & Dissertations

Dolutegravir (DTG) is a potent human immunodeficiency virus type 1 (HIV-1) integrase strand-transfer inhibitor (INSTI) with a high barrier to viral drug resistance. However, opportunities to improve its profile abound. These include extending the drug’s apparent half-life, increasing penetrance to “putative” viral reservoirs, and reducing inherent toxicities. These highlight, in part, the need for long-acting, slow effective release antiretroviral therapy (LASER ART) delivery schemes. A long-acting (LA) DTG was made by synthesizing a hydrophobic and lipophilic prodrug encased with poloxamer (P407) surfactant. This modified DTG (MDTG) reduced systemic metabolism and polarity, increased lipophilicity and membrane permeability, improved encapsulation, and formed …

Development Of Polymeric Carriers For The Treatment Of Acute Kidney Injury, Yi Chen

Theses & Dissertations

Acute kidney injury (AKI) is a major kidney disease associated with high mortality and morbidity. Long-term AKI may lead to chronic kidney disease and end-stage renal disease. Several clinical trials failed due to lack of efficacy and undesired side effects. Studies showed that macromolecular delivery systems would be a promising method to target kidney, however, little is known about how physicochemical properties affects the polymers deposition in ischemia-reperfusion (I/R) AKI.

Gene therapy has been well studied as a promising therapeutic agent for several diseases, including cancer and AKI. Although small interfering RNA (siRNA) has been commonly used to treat AKI …

Novel Therapeutic Approaches For Juvenile Neuronal Ceroid Lipofuscinosis (Cln3), Megan Elizabeth Bosch

Theses & Dissertations

Juvenile Neuronal Ceroid Lipofuscinosis (JNCL) is a lysosomal storage disease caused by autosomal recessive mutations in CLN3. Neuronal loss is thought to occur via glutamate excitotoxicity; however, little is known about neuron-astrocyte glutamate regulation in JNCL. We discovered that Cln3^Δex7/8 astrocytes have significantly lower basal spontaneous Ca²⁺ oscillations and decreased responses to glutamate, indicating a disrupted signaling network. Cln3^Δex7/8 astrocytes also displayed significantly lower basal mitochondrial respiration and ATP production, suggesting impaired metabolic functions. Concurrent with diminished astrocyte metabolism and Ca²⁺ signaling, Cln3^Δex7/8 neurons were hyper-responsive to glutamate stimulation. These studies suggest that CLN3 …

Novel Therapeutic Strategies For Treatment Of Castration-Resistant Prostate Cancer, Matthew A. Ingersoll

Theses & Dissertations

Prostate cancer (PCa) remains the most commonly diagnosed solid tumor and is the third leading cause of cancer-related death in United States men. While androgen deprivation therapy is the current standard-of-care treatment for metastatic PCa, most patients eventually relapse and develop castration-resistant (CR) tumors, for which there is currently no effective treatment. Therefore, synthesis of novel therapeutic agents and identification of alternative target proteins are necessary to improve treatment. Herein, I investigate the efficacy of novel imidazopyridine and statin derivatives as alternative therapeutic compounds. These molecules not only inhibit androgen receptor signaling, but also block activation of the AKT axis, …

Stability And Kinetics Of Dna Pseudoknots: Formation Of T∗A•T Base-Triplets And Their Targeting Reactions, Calliste Steffensmeier

Theses & Dissertations

Pseudoknots have been found to play important roles in the biology of RNA. These stem-loop motifs are considered to be very compact and the targeting of their loops with complementary strands is accompanied with lower favorable free energy terms. We used a combination of spectroscopic (UV, CD and fluorescence), calorimetric (DSC, PPC and ITC) and kinetic (SPR) techniques to investigate: 1) Local base-triplet formation in pseudoknots; 2) energetic contributions for the association of pseudoknots with their complementary strands; and 3) the kinetic rates as a function of targeting strand length.

We investigated a set of DNA pseudoknots with sequence: d(TCTCT …

Synthesis And Development Of Long-Acting Abacavir Prodrug Nanoformulations, Dhirender Singh

Theses & Dissertations

Over the past decade, work from our laboratory has demonstrated the potential of targeted nanoformulated antiretroviral therapy (nanoART) to produce sustained high plasma and tissue drug concentrations for weeks following a single intramuscular (IM) administration that can suppress ongoing viral replication and mitigate dose associated viral resistance. While progress has occurred towards developing long-acting nanoformulations for protease and nonnucleoside reverse transcriptase (RT) inhibitors, development of nanoformulations of hydrophilic nucleoside RT inhibitor drugs have remained elusive. Abacavir (ABC); a hydrophilic molecule exhibited limited utilities to develop into long-acting nanoformulation platform. Furthermore, inefficient conversion of ABC to its biological active metabolites; carbovir …