Matching Items (100)
Description
Breast cancer is the most common disease among women and the second most common disease worldwide, accounting for 2.09 million new cases of cancer diagnosis in 2018. It accounts for 11.6% of all cancer cases and is the leading cause of cancer mortality for women as well as the fourth cause of cancer death overall. HER2-positive breast cancer is distinguished as a distinct subtype of breast cancer by the overexpression of HER2, a specific protein found on the surface of cancer cells. Because targeted medicines precisely target the overexpression of the HER2 protein, the management of HER2-positive breast cancer has undergone a complete revolution. Monoclonal antibodies targeting the extracellular domain of the HER2 protein were regarded to be a step forward in the treatment of breast cancer; however, affibody-DNA nanoparticles in particular offer a paradigm-shifting picture of cancer treatment and diagnostics. The advantages of affibody DNA nanoparticles include targeted distribution, customization, small size, potential for combination therapy, and unique character. These attributes make them a promising alternative to monoclonal antibodies, the current standard therapy, in the treatment of HER2 positive breast cancer. The purpose of this paper is to provide information on the most promising recently developed nanoparticle-based therapies for the diagnosis and management of HER-2-positive breast cancer.
ContributorsAndreyeva, Anastasiya (Author) / Chen, Shengxi (Thesis director) / Lake, Douglas (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor) / School of Art (Contributor)
Created2024-05
Description
The treatment of melanoma is dependent on what stage the cancer has developed into. Metastatic melanoma is commonly treated with immune checkpoint inhibitors. Unfortunately, not all patients will respond to the treatment as expected. This paper develops important background knowledge on melanoma, how it is treated for each stage, and immune checkpoint inhibitors.
ContributorsStates, Savanna (Author) / Lake, Douglas (Thesis director) / Chang, Yung (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2024-05
Description
Background: Eosinophilic esophagitis (EoE) is an increasingly prevalent allergic disease characterized by eosinophilic inflammation and symptoms of esophageal dysfunction. Diagnosis and monitoring require repeated, invasive endoscopic esophageal biopsies to assess levels of eosinophilic inflammation. Recently, the minimally invasive esophageal string test (EST) has been used collect protein in mucosal secretions as a surrogate for tissue biopsies in monitoring disease activity. From the string, assessment of the eosinophil-associated proteins major basic protein-1 (MBP-1) and eotaxin-3 (Eot3) is used to assess disease activity; however, this requires measurement in a reference laboratory, for which the turnaround time for results exceeds the time required for histopathologic assessment of endoscopic biopsies. In addition, MBP-1 and Eot3 are not markers unique to eosinophils. These obstacles can be overcome by targeting eosinophil peroxidase (EPX), an eosinophil-specific protein, using a rapid point-of-care test. Currently, EPX is measured by a labor-intensive enzyme-linked immunosorbent assay (ELISA), but we sought to optimize a rapid point-of-care test to measure EPX in EST segments.
Methods: We extracted protein from residual EST segments and measured EPX levels by ELISA and a lateral flow assay (LFA).
Results: EPX levels measured by LFA strongly correlated with those quantified by ELISA
(rs = 0.90 {95% CI: 0.8283, 0.9466}). The EPX LFA is comparable to ELISA for measuring EPX levels in ESTs.
Conclusions: The EPX LFA can provide a way to rapidly test EPX levels in ESTs in clinical settings and may serve as a valuable tool to facilitate diagnosis and monitoring of EoE.
ContributorsDao, Adelyn (Author) / Lake, Douglas (Thesis director) / Borges, Chad (Committee member) / Wright, Benjamin (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor)
Created2024-05
Description
To combat the global antimalarial resistance crisis effective resistance management strategies are needed. To do so, I need to gain a better understanding of the ecological interactions occurring within malaria infections. Despite the importance of the complex interplay among co-infecting strains, our current knowledge and empirical data of within-host diversity and malaria disease dynamics is limited. In this thesis, I explore the multifaceted dynamics of malaria infections through an ecological lens. My overall research question is: "How do ecological interactions, including niche complementarity, competition dynamics, and the cost of resistance, shape the outcomes of malaria infections, and what implications does this have on understanding and improving resistance management strategies?” In Chapter II, titled “Niche Complementarity in Malaria Infections” I demonstrate that ecological principles are observed in malarial infections by experimentally manipulating the biodiversity of rodent malaria P. chabaudi infections. I observed that some parasites experienced competitive suppression, others experienced competitive facilitation, while others were not impacted. Next, in Chapter III, titled “Determining the Differential Impact of Competition Between Genetically Distinct Plasmodium falciparum Strains” I investigate the differential effect of competition among six genetically distinct strains. The impact of competition varied between strain combinations, and both suppression and facilitation were observed, but most pairings had no competitive interactions. Lastly, in Chapter IV, titled “Assessing Fitness Costs in Malaria Parasites: A Comprehensive Review and Implications for Drug Resistance Management”, I summarize where the field currently stands and what evidence there is for the presence of a fitness cost, or lack thereof, and I highlight the current gaps in knowledge. I found that evidence from field, in vitro, and animal models are overall suggestive of the presence of a fitness cost, however, these costs were not always found. Amid the current focus on malaria eradication, it is crucial to understand the impact of biodiversity on disease severity. By incorporating an ecological approach to infectious disease systems, I can gain insights on within-host interactions and how they impact parasite fitness and transmissibility.
ContributorsSegovia, Xyonane (Author) / Huijben, Silvie (Thesis advisor) / Bean, Heather (Committee member) / Gile, Gillian (Committee member) / Hogue, Ian (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2024
Description
Peptide-based vaccines represent a promising strategy to develop personalized treatments for cancer immunotherapy. Despite their specificity and low cost of production, these vaccines have had minimal success in clinical studies due to their lack of immunogenicity, creating a need for more effective vaccine designs. Adjuvants can be incorporated to enhance their immunogenicity by promoting dendritic cell activation and antigen cross-presentation. Due to their favorable size and ability to incorporate peptides and adjuvants, nanoparticles represent an advantageous platform for designing peptide vaccines. One prime example is RNA origami (RNA-OG) nanostructures, which are nucleic acid nanostructures programmed to assemble into uniform shapes and sizes. These stable nanostructures can rationally incorporate small molecules giving them a wide array of functions. Furthermore, RNA-OG itself can function as an adjuvant to stimulate innate immune cells. In the following study, self-adjuvanted RNA-OG was employed as a vaccine assembly platform, incorporating tumor peptides onto the nanostructure to design RNA-OG-peptide nanovaccines for cancer immunotherapy. RNA-OG-peptide was found to induce dendritic cell activation and antigen cross-presentation, which mobilized tumor-specific cytotoxic T cells to elicit protective anti-tumor immunity in tumor-bearing mice. These findings demonstrate the therapeutic potential of RNA-OG as a stable, carrier-free nanovaccine platform. In an attempt to further enhance the efficacy by optimizing the amount of peptides assembled, RNA-OG was complexed with polylysine-linked peptides, a simple strategy that allowed peptide amounts to be varied. Interestingly, increasing the peptide load led to decreased vaccine efficacy, which was correlated with an ineffective CD8+ T cell response. On the other hand, the vaccine efficacy was improved by decreasing the amount of peptide loaded onto RNA-OG, which may have attributed to greater complex stability compared to the high peptide load. These results highlight a simple strategy that can be used to optimize vaccine efficacy by altering the load of assembled peptides. These studies advance our understanding of RNA-OG as a peptide vaccine platform and provide various strategies to improve the design of peptide vaccines for translation into cancer immunotherapy.
ContributorsYip, Theresa (Author) / Chang, Yung (Thesis advisor) / Borges Florsheim, Esther (Committee member) / Lake, Douglas (Committee member) / Yan, Hao (Committee member) / Arizona State University (Publisher)
Created2024
Description
Signal transduction networks comprising protein-protein interactions (PPIs) mediate homeostatic, diseased, and therapeutic cellular responses. Mapping these networks has primarily focused on identifying interactors, but less is known about the interaction affinity, rates of interaction or their regulation. To better understand the extent of the annotated human interactome, I first examined > 2500 protein interactions within the B cell receptor (BCR) signaling pathway using a current, cutting-edge bioluminescence-based platform called “NanoBRET” that is capable of analyzing transient and stable interactions in high throughput. Eighty-three percent (83%) of the detected interactions have not been previously reported, indicating that much of the BCR pathway is still unexplored. Unfortunately, NanoBRET, as with all other high throughput methods, cannot determine binding kinetics or affinities. To address this shortcoming, I developed a hybrid platform that characterizes > 400 PPIs quantitatively and simultaneously in < 1 hour by combining the high throughput and flexible nature of nucleic programmable protein arrays (NAPPA) with the quantitative abilities of surface plasmon resonance imaging (SPRi). NAPPA-SPRi was then used to study the kinetics and affinities of > 12,000 PPIs in the BCR signaling pathway, revealing unique kinetic mechanisms that are employed by proteins, phosphorylation and activation states to regulate PPIs. In one example, activation of the GTPase RAC1 with nonhydrolyzable GTP-γS minimally affected its binding affinities with phosphorylated proteins but increased, on average, its on- and off-rates by 4 orders of magnitude for one-third of its interactions. In contrast, this phenomenon occurred with virtually all unphosphorylated proteins. The majority of the interactions (85%) were novel, sharing 40% of the same interactions as NanoBRET as well as detecting 55% more interactions than NanoBRET. In addition, I further validated four novel interactions identified by NAPPA-SPRi using SDS-PAGE migration and Western blot analyses. In one case, we have the first evidence of a direct enzyme-substrate interaction between two well-known proto-oncogenes that are abnormally regulated in > 30% of cancers, PI3K and MYC. Herein, PI3K is demonstrated to phosphorylate MYC at serine 62, a phosphosite that increases the stability of MYC. This study provides valuable insight into how PPIs, phosphorylation, and GTPase activation regulate the BCR signal transduction pathway. In addition, these methods could be applied toward understanding other signaling pathways, pathogen-host interactions, and the effect of protein mutations on protein interactions.
ContributorsPetritis, Brianne Ogata (Author) / LaBaer, Joshua (Thesis advisor) / Lake, Douglas (Committee member) / Wang, Shaopeng (Committee member) / Arizona State University (Publisher)
Created2018
Description
Quiescin sulfhydryl oxidase 1 (QSOX1) is an enzyme that catalyzes disulfide bond formation by oxidizing two free sulfhydryl groups. QSOX1 consists of a thioredoxin (Trx) and an ERV (essential for respiration and viability)/ALR (augmenter of liver regeneration) domain which each contain CxxC motifs that work to bind to substrates and shuttle electrons to a flavin adenine dinucleotide (FAD) cofactor that accepts the electrons and reduces molecular oxygen to hydrogen peroxide. Investigation of the role of QSOX1 in cancer progression started when it was found at higher abundance in pancreatic ductal adenocarcinoma (PDA) patient plasma compared to healthy normal donor plasma. Increased expression in QSOX1 has been further identified in breast, lung, kidney, prostate, and other cancers. QSOX1 expression is associated with cell proliferation and invasion in vitro and tumor growth in vivo. Additionally, the enzymatic activity of QSOX1 in the extracellular matrix (ECM) is important for cell invasion in vitro. Small molecule inhibitors of QSOX1 have been shown to have antitumorigenic properties in vitro and in vivo. It was hypothesized that monoclonal antibodies (mAbs) against QSOX1 would inhibit cell invasion in vitro. In this work, mice were immunized with eukaryotic-derived rQSOX1 for generation of hybridomas. Hundreds of hybridoma clones were screened by enzyme-linked immunosorbent assay (ELISA) and a fluorescent QSOX1 activity assay. Multiple rounds of subcloning and screening identified 2F1.14 and 3A10.6 as mAbs of interest. The genes for the variable regions of the antibodies were rescued and sequenced. The sequences were aligned with the variable region sequences of another published αQSOX1 mAb scFv492.1. 2F1.14 inhibits the enzymatic activity of QSOX1 by binding to the active site of QSOX1, which was determined by epitope mapping against mutants of QSOX1 that contained mutations in the active site. 3A10.6 did not appear to inhibit the function of QSOX1 in the activity assay; however, it, along with 2F1.14, suppressed tumor invasion in a 3D invasion model. These findings support the developing idea that QSOX1 is a viable target for cancer treatment because targeted inhibition of QSOX1 extracellularly reduced invasive activity. The mAbs and rQSOX1 variants produced here can serve as tools in furthering the characterization of QSOX1 and its role in cancer.
ContributorsKoelbel, Calvin John (Author) / Lake, Douglas (Thesis advisor) / Chen, Qiang "Shawn" (Committee member) / Ho, Thai (Committee member) / Arizona State University (Publisher)
Created2019
Description
Antibodies are naturally occurring proteins that protect a host during infection through direct neutralization and/or recruitment of the innate immune system. Unfortunately, in some infections, antibodies present unique hurdles that must be overcome for a safer and more efficacious antibody-based therapeutic (e.g., antibody dependent viral enhancement (ADE) and inflammatory pathology). This dissertation describes the utilization of plant expression systems to produce N-glycan specific antibody-based therapeutics for Dengue Virus (DENV) and Chikungunya Virus (CHIKV). The Fc region of an antibody interacts with Fcγ Receptors (FcγRs) on immune cells and components of the innate immune system. Each class of immune cells has a distinct action of neutralization (e.g., antibody dependent cell-mediated cytotoxicity (ADCC) and antibody dependent cell-mediated phagocytosis (ADCP)). Therefore, structural alteration of the Fc region results in novel immune pathways of protection. One approach is to modulate the N-glycosylation in the Fc region of the antibody. Of scientific significance, is the plant’s capacity to express human antibodies with homogenous plant and humanized N-glycosylation (WT and GnGn, respectively). This allows to study how specific glycovariants interact with other components of the immune system to clear an infection, producing a tailor-made antibody for distinct diseases. In the first section, plant-produced glycovariants were explored for reduced interactions with specific FcγRs for the overall reduction in ADE for DENV infections. The results demonstrate a reduction in ADE of our plant-produced monoclonal antibodies in in vitro experiments, which led to a greater survival in vivo of immunodeficient mice challenged with lethal doses of DENV and a sub-lethal dose of DENV in ADE conditions. In the second section, plant-produced glycovariants were explored for increased interaction with specific FcγRs to improve ADCC in the treatment of the highly inflammatory CHIKV. The results demonstrate an increase ADCC activity in in vitro experiments and a reduction in CHIKV-associated inflammation in in vivo mouse models. Overall, the significance of this dissertation is that it can provide a treatment for DENV and CHIKV; but equally importantly, give insight to the role of N-glycosylation in antibody effector functions, which has a broader implication for therapeutic development for other viral infections.
ContributorsHurtado, Jonathan (Author) / Chen, Qiang (Thesis advisor) / Arntzen, Charles (Committee member) / Borges, Chad (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2019
Description
Small Cell Carcinoma of the Ovary Hypercalcemic Type (SCCOHT) is a rare and highly aggressive ovarian cancer that affects children and young women at a mean age of 24 years. Most SCCOHT patients are diagnosed at an advanced stage and do not respond to chemotherapy. As a result, more than 75% of patients succumb to their disease within 1-2 years. To provide insights into the biological, diagnostic, and therapeutic vulnerabilities of this deadly cancer, a comprehensive characterization of 22 SCCOHT cases and 2 SCCOHT cell lines using microarray and next-generation sequencing technologies was performed. Following histological examination, tumor DNA and RNA were extracted and used for array comparative genomic hybridization and gene expression microarray analyses. In agreement with previous reports, SCCOHT presented consistently diploid profiles with few copy number aberrations. Gene expression analysis showed SCCOHT tumors have a unique gene expression profile unlike that of most common epithelial ovarian carcinomas. Dysregulated cell cycle control, DNA repair, DNA damage-response, nucleosome assembly, neurogenesis and nervous system development were all characteristic of SCCOHT tumors. Sequencing of DNA from SCCOHT patients and cell lines revealed germline and somatic inactivating mutations in the SWI/SNF chromatin-remodeling gene SMARCA4 in 79% (19/24) of SCCOHT patients in addition to SMARCA4 protein loss in 84% (16/19) of SCCOHT tumors, but in only 0.4% (2/485) of other primary ovarian tumors. Ongoing studies are now focusing on identifying treatments for SCCOHT based on therapeutic vulnerabilities conferred by ubiquitous inactivating mutations in SMARCA4 in addition to gene and protein expression data. Our characterization of the molecular landscape of SCCOHT and the breakthrough identification of inactivating SMARCA4 mutations in almost all cases of SCCOHT offers the first significant insight into the molecular pathogenesis of this disease. The loss of SMARCA4 protein is a highly sensitive and specific marker of the disease, highlighting its potential role as a diagnostic marker, and offers the opportunity for genetic testing of family members at risk. Outstanding questions remain about the role of SMARCA4 loss in the biology, histogenesis, diagnosis, and treatment of SCCOHT.
ContributorsRamos, Pilar (Author) / Anderson, Karen (Thesis advisor) / Trent, Jeffrey (Committee member) / Kusumi, Kenro (Committee member) / Lake, Douglas (Committee member) / Arizona State University (Publisher)
Created2014
Description
Evidence from the 20th century demonstrated that early life stress (ELS) produces long lasting neuroendocrine and behavioral effects related to an increased vulnerability towards psychiatric illnesses such as major depressive disorder, post-traumatic stress disorder, schizophrenia, and substance use disorder. Substance use disorders (SUDs) are complex neurological and behavioral psychiatric illnesses. The development, maintenance, and relapse of SUDs involve multiple brain systems and are affected by many variables, including socio-economic and genetic factors. Pre-clinical studies demonstrate that ELS affects many of the same systems, such as the reward circuitry and executive function involved with addiction-like behaviors. Previous research has focused on cocaine, ethanol, opiates, and amphetamine, while few studies have investigated ELS and methamphetamine (METH) vulnerability. METH is a highly addictive psychostimulant that when abused, has deleterious effects on the user and society. However, a critical unanswered question remains; how do early life experiences modulate both neural systems and behavior in adulthood? The emerging field of neuroepigenetics provides a potential answer to this question. Methyl CpG binding protein 2 (MeCP2), an epigenetic tag, has emerged as one possible mediator between initial drug use and the transition to addiction. Additionally, there are various neural systems that undergo long lasting epigenetics changes after ELS, such as the response of the hypothalamo-pituitary-adrenal (HPA) axis to stressors. Despite this, little attention has been given to the interactions between ELS, epigenetics, and addiction vulnerability. The studies described herein investigated the effects of ELS on METH self-administration (SA) in adult male rats. Next, we investigated the effects of ELS and METH SA on MeCP2 expression in the nucleus accumbens and dorsal striatum. Additionally, we investigated the effects of virally-mediated knockdown of MeCP2 expression in the nucleus accumbens core on METH SA, motivation to obtain METH under conditions of increasing behavioral demand, and reinstatement of METH-seeking in rats with and without a history of ELS. The results of these studies provide insights into potential epigenetic mechanisms by which ELS can produce an increased vulnerability to addiction in adulthood. Moreover, these studies shed light on possible novel molecular targets for treating addiction in individuals with a history of ELS.
ContributorsLewis, Candace (Author) / Olive, M. Foster (Thesis advisor) / Hammer, Ronald (Committee member) / Neisewander, Janet (Committee member) / Sanabria, Federico (Committee member) / Arizona State University (Publisher)
Created2015