Medicine and Health Sciences Commons^™

Characterizing The Combination Of Rpa Inhibitors With Parp Inhibitors In High-Grade Serous Ovarian Cancer, Yat Tang

Theses & Dissertations

High-grade serous ovarian cancer (HGSC) is the most common and deadly gynecologic malignancy. HGSC patients with BRCA1/2 mutations have homologous recombination deficiency (HRD), requiring parallel pathways to maintain genome integrity (e.g., PARP1, PARP2). Approximately 50% of ovarian carcinomas are estimated to exhibit HRD. For the remaining 50% and the large percentage of HRD patients with acquired or innate resistance to single-agent PARP inhibitors, there is a need to develop alternative therapeutic strategies.

Replication Protein A (RPA) is a heterotrimeric protein crucial for genome maintenance. Phosphorylation of RPA in DNA damage response (DDR) is a negative regulator of DNA end resection. …

The Role Of Histone Chaperone Fact Complex In Base Excision Repair Pathway And Its Therapeutic Potential In Colon Cancer And Medulloblastoma, Heyu Song

Theses & Dissertations

Base excision repair (BER) pathway is required for the removal of damaged bases caused by alkylation, oxidation and ring-saturation. Human apurinic/apyrimidinic endonuclease 1 (APE1) plays a central role in BER pathway. Although repair of damaged bases by recombinant APE1 has been well investigated in vitro, how APE1 gains access to damaged bases in the context of chromatin is largely unknown. A prominent member of the histone chaperone family, FACT (Facilitates Chromatin Transcription) is thought to reorganize nucleosomes through the destabilization of multiple intra-nucleosome contacts. FACT complex is composed of two polypeptides identified as SPT16 (Suppressor of Ty 16) and SSRP1 …

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 …

Delivery Of Small Molecule And Rna Using Synthetic Polymeric Micelles And Multifunctional Exosomes For The Treatment Of Type 1 Diabetes, Yang Peng

Theses & Dissertations

Type 1 diabetes is one of the most challenging chronic autoimmune diseases. The destruction and dysfunction of insulin-secreting β cells are the results of inflammatory infiltration and the synergistic effect of multiple immune cells. The aim of this dissertation is to develop novel and reliable therapeutic approaches to advance the treatment of T1D: including chemical modification of a broad-spectrum immunosuppressant, co-application of small molecule based immune intervention and siRNA based β cell preservative therapy, and administration of a PI3K-δ/γ dual inhibitor to specifically target immune cells, utilizing synthetic polymeric micelles or natural produced multi-functional exosomes derived from human bone marrow …

Hiv-1 Elimination In Humanized Mice, Hang Su

Theses & Dissertations

Human immunodeficiency virus type one (HIV-1) exclusively infects humans and chimpanzees. Therefore, animal models are required for all investigations of viral pathogenesis, therapy and cure. Immunodeficient mice transplanted with human hematopoietic stem cells, termed humanized mice, support the development of multiple human cell lineages throughout the cell’s life span. To this end, we used humanized mice to evaluate the dynamic changes of host immunologic and viral profiles during both acute and chronic HIV-1 infection. We identified the temporal and spatial distribution of HIV-1 cell and tissue compartment infections and outlined correlations made between viral progression and host immunity by comparing …

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. …

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 …

Defining The Role Of Tyrosine Phosphorylation In The Regulation Of Connexin43 In Cardiac Diseases, Li Zheng

Theses & Dissertations

Connexins are integral membrane proteins that oligomerize to form gap junction channels. Ions and small molecules diffuse intercellularly through these channels, allowing individual cellular events to synchronize into the functional response of an entire organ. Gap junction channels composed of Connexin43 (Cx43) mediate electrical coupling and impulse propagation in the normal working myocardium. In the failing heart, Cx43 remodeling (decreased expression, altered phosphorylation state, loss at intercalated discs, and increased presence at lateral membranes) contributes to rhythm disturbances and contractile dysfunction. While there is considerable information regarding key interactions of Cx43 in the regulation of gap junction channels, unfortunately, the …

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 …

Synthesis And Characterization Of Long-Acting Rilpivirine Prodrugs, James R. Hilaire

Theses & Dissertations

Antiretroviral therapy (ART) requires lifelong daily dosing to suppress viral replication, restore or maintain immune function and improve quality of life. As an alternative, long-acting (LA) antiretrovirals (ARVs) aim to deliver therapeutic drug concentrations over an extended period, ultimately requiring monthly or even more extended dosing intervals. Specifically, the success of recent clinical trials examining LA cabotegravir and rilpivirine (CAB and RPV LA) highlight the advent of these novel HIV-1 therapeutics. Further optimization of LA dosage forms are required and rests upon improving dosing frequency, injection volumes and tissue distribution to viral compartments. To this end, we report the synthesis …

Evaluation Of The Role Of Microvascular Pathology On Peripheral Artery Disease, Constance Mietus

Theses & Dissertations

Background: Peripheral Artery Disease (PAD) begins with atherosclerotic narrowing of arteries, including those that supply the legs. Individuals with PAD experience pain during walking, which becomes increasingly limiting. Studies from our group and others have shown that a myopathy is present in the skeletal muscle of PAD patients, and is characterized by myofiber degeneration, fibrosis, and remodeling of vessels ranging from 50 – 150 mm in diameter. However, microvascular pathology, particularly of the smallest microvessels (5 – 15 mm in diameter) remains poorly characterized. Furthermore, little is known about the relationships between microvascular architecture, microperfusion, and patient walking performance. We …

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 …

Role Of Rac1-Pak Pathway In Aggressive B-Cell Lymphoma, Tian Tian

Theses & Dissertations

Aggressive B-cell lymphomas are diverse group of neoplasms that arise at different stages of B-cell development and by various mechanisms of neoplastic transformation. Aggressive B-cell lymphomas include many types, subtypes and variants of diffuse large B-cell lymphoma (DLBCL), Burkitt lymphoma (BL), mantle cell lymphoma (MCL) and B lymphoblastic lymphoma. The treatment of patients with aggressive B-cell lymphomas remains a clinical challenge. Conventional chemotherapeutic regimens, mainly based on the CHOP (cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone) combination, obtain a relatively high number of complete or partial clinical responses (20-80%), but the tumor relapses in most patients, who will die of the disease. …

The Role Of Ros In The Progression And Treatment Of Castration-Resistant Prostate Cancer, Dannah R. Miller

Theses & Dissertations

Prostate cancer is the second leading cause of cancer-related deaths in U.S. men, primarily due to the development of castration-resistant (CR) prostate cancer (PCa), of which there are no effective treatment options. Reactive oxygen species (ROS) plays a critical role in prostate carcinogenesis, including the progression of the CR PCa phenotype. ROS regulates both cell proliferation and apoptosis; a moderate increase in ROS can promote proliferation; however, a substantial rise in ROS levels will result in apoptosis. Oxidase p66Shc is elevated in clinical PCa cells and has been associated with a metastatic phenotype of CR PCa cells, promoting PCa cell …