Medical Cell Biology Commons^™

Wnt5b As A Therapeutic Target For Osteosarcoma Stemness, Metastasis, And Chemoresistance, Rachel S. Perkins

Alternative Theses and Dissertations (AETDs)

Osteosarcoma is a pediatric bone cancer that has no targeted therapy and has had no treatment advances for the last three decades. Osteosarcoma frequently metastasizes to the lungs and is highly chemotherapy resistant, reducing patient survival with metastatic disease to 20% after 5 years. New therapies targeted to metastasis and drug resistance in osteosarcoma are essential to improving patient outcomes.

Osteosarcoma is a pediatric bone cancer that has no targeted therapy and has had no treatment advances for the last three decades. Osteosarcoma frequently metastasizes to the lungs and is highly chemotherapy resistant, reducing patient survival with metastatic disease to …

Characterizing The Cellular Response To Astrovirus Infection In The Central Nervous System, Amy E. Davis

Theses and Dissertations (ETD)

Central nervous system (CNS) diseases caused by infectious agents pose significant health challenges, often leading to severe neurological dysfunction with high morbidity and mortality rates. Astroviruses (AstVs), traditionally known for causing gastroenteritis, have recently been identified as neuroinvasive pathogens capable of inducing neurological diseases. This study explores the cellular and molecular mechanisms by which AstV, specifically non-classical VA1 and classical HAstV1 genotypes, induce CNS pathology in human neurons and astrocytes. Utilizing primary human neurons and astrocytes from various brain regions, this research investigates the cytotoxic effects, apoptotic pathways, and inflammatory responses triggered by these viruses. This study reveals that VA1 …

Molecular Determinants Of Trp Channel Gating, Briar J. Bell

Theses and Dissertations (ETD)

Transient Receptor Potential (TRP) ion channels are a family of proteins that contribute to a myriad of physiological functions. They have been extensively studied since their discovery 35 years ago; however, there are still many questions regarding the mechanisms by which they function. This family of proteins is characterized by a generally shared structure: an intracellular N terminus featuring ankyrin repeats, six transmembrane helices including the pore domain, a re-entrant loop and TRP helix, and an intracellular C terminus with varying structure. Each of these regions has been implicated in the regular function of TRPs, while mutations that alter trafficking …

Studies On The Leukocyte-Associated Ig-Like Inhibitory Receptor-1 Signaling Pathway In T Lymphocytes, Chidi Zacheaus

Theses and Dissertations (ETD)

Inflammation is a natural process in which the immune system concertedly responds to pathogens and abnormal cell growth to protect the host. For an efficient/effective immune response that circumvents tissue atrophy, a delicate balance between stimulatory and inhibitory mechanisms is essential for the proper functioning of the immune system. Immuno-receptor Tyrosine-based Inhibitory Motif (ITIM)-bearing receptors in immune cells, including T lymphocytes, play a major role in preventing autoimmune responses. Leukocyte-associated Ig-like Inhibitory Receptor 1 (LAIR-1) is one of ITIM-bearing receptors. The mechanism by which LAIR-1 attenuates T-cell response has yet to be completely understood. In this study, I investigated a …

The Interaction Between Host G3bp And Viral Nucleocapsid Protein Regulates Sars-Cov-2 Replication, Zemin Yang

Theses and Dissertations (ETD)

G3BP1/2 are RNA-binding proteins that promote condensation to form stress granules in response to various cellular stresses, including viral infection. G3BP1/2 are prominent interactors of the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the functional consequences of the G3BP-N interaction in the context of viral infection have remained unclear. Here we used structural and biochemical analyses to define the residues required for G3BP1-N interaction, followed by structure-guided mutagenesis of G3BP1 and N to selectively disrupt their interaction. We found that mutation of N-F17 led to selective loss of interaction with G3BP1 and consequent failure of …

Tcf4 Is A Key Mediator Of Cell Identity And Oncogenesis In Neuroblastoma, Nour Aljouda

Theses and Dissertations (ETD)

Neuroblastomas (NB) are embryonal childhood tumors that derive from the multipotent neural crest cells (NCCs) of the peripheral nervous system. NB accounts for more than 15% of all childhood cancer-related deaths. Despite the most intensive multimodal therapy, more than 50% of patients with high-risk NB relapse with often fatal, resistant disease. Novel therapies are desperately needed to improve cure rates. Previous studies proposed that the deregulation of normal neural crest developmental programs contributes to NB oncogenesis by retaining the highly migratory and proliferative traits of NCCs. Thus, activation or repression of neural crest developmental pathways have been implicated in NB …

A Design, Development, And Evaluation Of Bio-Patch For Myocardial Tissue Repair, Yaya Zhang

Theses and Dissertations (ETD)

Introduction. Ischemic heart disease (IHD) is a major concern of human health issue. The structural repair and functional recovery of injured hearts is a major challenge in the clinical setting. Preclinical studies over last 10 years have demonstrated the potential of using stem cells to treat IHD, but the efficacy of this therapy is jeopardized by uncontrollable migration and low survival of the injected stem cells. An approach based on tissue engineering enabling target-specific stem cell delivery such as cardiac patches has emerged as an alternative solution for stem cell therapy for IHD. It employs scaffold materials to engulf various …

Mitophagy-Mediated Regulation Of Ros Homeostasis During Hsc Activation Contributes To Cell Fate, Amber Lynne Smith

Theses and Dissertations (ETD)

The ability of hematopoietic stem cells to self-renew and differentiate is required for the maintenance of all blood lineages under basal physiologic conditions and in response to inflammatory stress. The degradative capacity of the autophagy-lysosomal system is a determinant of hematopoietic stem cell (HSC) activation status with low autophagy predicting activation of HSCs, and autophagy deficiency causing the spontaneous loss of quiescence and HSC exhaustion. Although an increase in mitochondrial activity has been suggested as the cause of HSC depletion in autophagy-defective models, the contribution of mitophagy to HSC function remains to be elucidated. Here, we capitalized on the observation …

Developing Targeted Therapies For T-Cell Acute Lymphoblastic Leukemia, Jianzhong Hu

Theses and Dissertations (ETD)

Introduction Acute lymphoblastic leukemia (ALL) is the most common cancer in children, and risk-adapted chemotherapies have dramatically improved the outcomes of this disease. Compared to B-cell ALL, T-cell ALL (T-ALL) is more aggressive and has worse outcomes from chemotherapy. There is a great unmet need to develop biomarkers and novel targeted therapies for this type of cancer. Working together with internal and external collaborators, we performed a large-scale pharmacotyping assay in over 300 primary ALL samples. By combining pharmacotypying and genomic profiling of these samples, we identified a substantial T-ALL population that showed strong response to dasatinib, a known ABL1 …

Immunomodulatory Roles Of The Lysosomal Sialidase Neuraminidase 1, Leigh Ellen Fremuth

Theses and Dissertations (ETD)

Background Sialic acids are key sugar moieties located at the non-reducing terminals of glycan chains on glycoproteins and glycolipids. By virtue of their location, they influence the functions and biochemical properties of the macromolecules they are bound to. Removal of sialic acids in mammalian cells is carried out by four sialidases, which are differentially expressed and localized in distinct subcellular compartments. Neuraminidase 1 (NEU1), the most abundant and ubiquitous of the four sialidases, functions primarily in the acidic environment of the lysosomes, but can hydrolyze substrates at the plasma membrane, at least in certain cell types. The enzyme initiates the …

Identifying The Molecular Cause Of Extreme Endoplasmic Reticulum Dilation In Pediatric Osteosarcoma And Its Relationship To The Disease, Rachael Wood

Theses and Dissertations (ETD)

Pediatric osteosarcoma tumors are characterized by an unusual abundance of grossly dilated endoplasmic reticulum and an immense genomic instability that has complicated identifying new effective molecular therapeutic targets. Here we report a novel molecular signature that encompasses the majority of 108 patient tumor samples, PDXs and osteosarcoma cell lines. These tumors exhibit reduced expression of four critical COPII vesicle proteins that has resulted in the accumulation of procollagen-I protein within ‘hallmark’ dilated ER. Using CRISPR activation technology, increased expression of only SAR1A and SEC24D to physiologically normal levels was sufficient to restore both collagen-I secretion and resolve dilated ER morphology …

Characterizing And Overcoming Resistance To Aminomethylspectinomycins In Gram-Negative Bacteria, Nisha Das

Theses and Dissertations (ETD)

Spectinomycin (SPC) is a broad-spectrum aminocyclitol antibiotic. Its use in agriculture has led to widespread resistance in enteric bacteria, necessitating the development of more effective analogs. Aminomethyl spectinomycins (amSPC) are modified spectinomycins with increased potency against many bacterial species. These species include Legionella pneumophila, which harbors a chromosomally encoded aminoglycoside modifying enzyme (AME). In this study, we follow up on this observation and examine the extent to which the amSPCs are substrates for AMEs through adenylation (ANTs) and phosphorylation (APH). APH(9)-Ia and ANT(3")(9) were expressed in E. coli BL21(DE3) and purified using the Ni-affinity chromatography. The ability of AMEs to …

The Effect Of Cancer Cachexia Progression On The Feeding Regulation Of Skeletal Muscle Protein Turnover, Brittany R. Franch

Theses and Dissertations (ETD)

Cancer cachexia is defined as the unintentional loss of skeletal muscle mass with or without fat loss that cannot be reversed by conventional nutritional support. Cachexia occurs in ~20% of cancer patients. More specifically, 50% of lung cancer patients, the most common cancer worldwide, develop cachexia. Cachexia occurs most often in lung and gastrointestinal cancers, whereas breast and prostate have the lowest rate of cachexia. Cancer-induced cachexia disrupts skeletal muscle protein turnover (decreasing protein synthesis and increasing protein degradation). Skeletal muscle’s capacity for protein synthesis is highly sensitive to local and systemic stimuli that are controlled by mTORC1 and AMPK …

The Molecular Mechanisms Of Estrogen Receptor Α On Two Single Nucleotide Polymorphisms To Regulate Wnt Signaling In Osteoblasts, Sarocha Suthon

Theses and Dissertations (ETD)

Osteoporosis is the most common bone metabolic disorder, affecting over 200 million people globally. It is characterized by bone mass depletion and microarchitectural deterioration, leading to bone fragility and susceptibility to bone fracture. Genetic factors, estrogen deficiency, and dysregulation of the WNT signaling pathway contribute to the development of this disease. Genome-wide association studies have predicted that the single nucleotide polymorphisms (SNPs) rs2887571 and rs9921222 associate with low bone mass, but the mechanism of these SNPs has remained unknown. Analysis of osteoblasts from 112 different joint replacement patients reveals that the genotype of rs2887571 correlates with WNT5B expression, and the …

Advancing Rna Virus Discovery And Biology With Whole Genome Sequencing, Mariah Katherine Taylor

Theses and Dissertations (ETD)

Two RNA virus families that pose a threat to human and animal health are Hantaviridae and Coronaviridae. These RNA viruses which originate in wildlife continue and will continue to cause disease, and hence, it is critical that scientific research define the mechanisms as to how these viruses spillover and adapt to new hosts to become endemic. One gap in our ability to define these mechanisms is the lack of whole genome sequences for many of these viruses. To address this specific gap, I developed a versatile amplicon-based whole-genome sequencing (WGS) approach to identify viral genomes of hantaviruses and severe acute …

Role Of Smad2 And Smad3 On Adipose Tissue Development And Function, Roshan Kumari

Theses and Dissertations (ETD)

Introduction: Obesity and its associated metabolic syndrome are major medical problems worldwide including United States. Adipose tissue is the primary site of energy storage, playing important roles in health. Adipose tissue also has other critical functions, producing adipocytokines and contributing to normal nutrient metabolism, which in turn play important roles in satiety, inflammation, and total energy homeostasis. Activin A and activin B play important roles in maintaining body composition and energy homeostasis. This dissertation highlights the role of activin/SMADs signaling in adipose tissue development, function, and maintenance.

SMAD2/3 proteins are downstream mediators of transforming growth factor-β (TGFβ) family signaling, including …

Implications Of The Quantum Dna Model For Information Sciences, F. Matthew Mihelic

Faculty Publications

The DNA molecule can be modeled as a quantum logic processor, and this model has been supported by pilot research that experimentally demonstrated non-local communication between cells in separated cell cultures. This modeling and pilot research have important implications for information sciences, providing a potential architecture for quantum computing that operates at room temperature and is scalable to millions of qubits, and including the potential for an entanglement communication system based upon the quantum DNA architecture. Such a system could be used to provide non-local quantum key distribution that could not be blocked by any shielding or water depth, would …

Therapeutic Potential Of Trp Channels In The Targeting Of Rheumatoid Arthritis Synovial Fibroblasts, Brittany Isabella Schwam

Theses and Dissertations (ETD)

Rheumatoid arthritis is a chronic inflammatory disease primarily affecting the synovium, articular cartilage, and bone within a joint, but it is a unique form of arthritis wherein effects are systemic. The cause of this autoimmune disease remains unknown, but there are many environmental and genetic factors that play into susceptibility. Research is still far from drug-free remission despite great advancements over the past few decades. The majority of therapies developed rely on immunosuppressant or immunomodulator molecules and come with risk of infection, high costs, and toxic, uncontrolled side effects. Those diagnosed maintain a significant unmet need for targeted therapies.

There …

The Heme-Regulated Inhibitor Pathway Modulates Susceptibility Of Poor Prognosis B-Lineage Acute Leukemia To Bh3-Mimetics, Kaitlyn Hill Smith

Theses and Dissertations (ETD)

Anti-apoptotic MCL1 is one of the most frequently amplified genes in human cancers and its elevated expression confers resistance to many therapeutics including the BH3-mimetic agents ABT-199 and ABT-263. The anti-malarial, dihydroartemisinin (DHA) translationally represses MCL-1 and synergizes with BH3-mimetics. To explore how DHA represses MCL-1, a genome-wide CRISPR screen identified that loss of genes in the heme synthesis pathway renders mouse BCR-ABL+ B-ALL cells resistant to DHA-induced death. Mechanistically, DHA disrupts the interaction between heme and the eIF2α kinase heme regulated inhibitor (HRI) triggering the integrated stress response. Genetic ablation of Eif2ak1, which encodes HRI, blocks MCL-1 repression in …

Investigating The Role Of Znf384 Rearrangements In Acute Leukemia, Kirsten Dickerson

Theses and Dissertations (ETD)

Chromosomal rearrangements involving ZNF384 are the defining lesion in 5% of pediatric and adult B-cell acute lymphoblastic leukemia and tumors are characterized by aberrant myeloid marker expression. Additionally, ZNF384 rearrangements are the defining lesion in nearly half of pediatric B/myeloid mixed phenotype acute leukemia. These fusions juxtapose full-length ZNF384 to the N terminal portion of a diverse range of partners, most often, transcription factors or epigenetic modifiers. It has been shown that ZNF384-rearranged tumors have a distinct gene expression profile that is consistent between disease groups and N terminal partners. Genomic analyses of patient tumors has shown that ZNF384 fusions …

Role Of Cerebral Vasculature And Effect Of Circulating Exosomes In Propagation Of Systemic Inflammatory Responses Into The Central Nervous System, Mahesh Chandra Kodali

Theses and Dissertations (ETD)

Sepsis-associated encephalopathy (SAE) is an acutely progressing brain dysfunction induced by systemic inflammation. The mechanism of initiation of neuroinflammation during SAE, which ultimately leads to delirium and cognitive dysfunction, remains elusive. The goal of this project was to study the molecular events of SAE to capture its onset and progression into the central nervous system (CNS), and further identify the cellular players involved in mediating acute inflammatory signaling. Gene expression profiling on the cerebral vessels isolated from the brains of the mice treated with peripheral lipopolysaccharide (LPS) revealed that the cerebral vasculature responds within minutes to acute systemic inflammation by …

Eukaryotic Initiation Factor 5a2 (Eif5a2) Contributes To Ovarian Tumor Growth And Metastasis, Guannan Zhao

Theses and Dissertations (ETD)

Ovarian cancer has the highest mortality rate among all gynecological malignancies due to lack of effective biomarkers for early diagnosis. The majority of ovarian cancer patients are already at an advanced stage when diagnosed. In addition, ovarian cancers often become chemoresistant and metastatic, and recur following initial chemotherapy.

Attenuation Of Interferon Responses In The Obese Host And Ramifications For Influenza Virus Evolution, Rebekah Reed Honce

Theses and Dissertations (ETD)

The most insidious pandemic of modern life does not arise from an infectious agent but rather from malnutrition. With its global incidence tripling over the past three decades, obesity is a major public health concern. Obesity’s rising prevalence has also illuminated its impact on communicable diseases. Following the 2009 H1N1 influenza A virus pandemic, obesity was identified as a risk factor for increased disease severity and mortality in infected individuals. Obesity causes a chronic state of meta-inflammation with systemic implications for immunity, including delayed antiviral responses to influenza virus infection, poor recovery, and impaired immunological memory. However, the majority of …

Genetic Variation And Sex Mediate Differential Responses To ∆-9-Tetrahydrocannabinol Among Inbred Mice, Cory Parks

Theses and Dissertations (ETD)

The plant Cannabis sativa has been used by people for both recreational and medicinal use for thousands of years, but scientific investigation of the plant and its components didn’t begin until the early nineteen hundreds when Cannabis components known as phytocannabinoids were characterized and later isolated. In the 1970’s, ∆9-tetrahydrocannabinol (THC) was isolated and recognized as the major constituent responsible for the psychoactive and intoxicating effects associated with consumption of cannabis. This opened the door for intensive research in the field that lead to the discovery of the endogenous cannabinoid system and its associated receptors, effectors of signaling, and biosynthetic …

Characterization Of Genome-Wide Binding Of Nuclear-Factor I-X In Hematopoietic Progenitor Cells, Megan J. Walker

Theses and Dissertations (ETD)

We report that ectopic expression of Nfix in primary mouse HSPC extended their ex vivo culture from 20 to 40 days. HSPC overexpressing Nfix displayed hypersensitivity to supportive cytokines and reduced apoptosis when subjected to cytokine deprivation compared to controls. Ectopic Nfix resulted in elevated levels of c-Mpl transcripts and cell surface protein on primary murine HSPC as well as increased phosphorylation of STAT5, which is known to be activated down-stream of c-MPL signaling. Blocking c-MPL signaling by removal of its ligand, thrombopoietin (TPO), or addition of a c-MPL neutralizing antibody negated the anti-apoptotic effect of Nfix overexpression on cultured …

The Characterization Of Hematopoiesis In Murine Fetal Bone Marrow, Trent Daniel Hall

Theses and Dissertations (ETD)

Hematopoietic stem cells (HSCs) and their downstream progenitors are a heterogeneous population of cells that are indispensable for lifelong hematopoiesis and are often utilized in the clinic for the treatment of hematologic maladies via hematopoietic stem cell transplantation (HSCT). Over several decades, it has been discovered that HSCs arise in the dorsal aorta of the developing embryo, migrate to the fetal liver (FL), and undergo a large expansion before reaching their final resting place in the bone marrow (BM). Many resources have been invested in understanding the roles of the different niches HSCs encounter along their journey. A greater understanding …

Conditional Loss Of Engrailed 1/2 In Rhombic Lip-Derived Neurons Increases Intrinsic Rhythmicity And Decreases Overall Variability Of Eupneic Respiration, Angela P. Taylor

Theses and Dissertations (ETD)

Evidence for a cerebellar role during cardiopulmonary challenges has long been established, but investigation into cerebellar involvement in eupneic breathing has been inconclusive. Given the view of the cerebellum (CRB) as a temporally coordinating structure, any investigation into the CRB during respiration must evaluate rhythm and variability of the respiratory sequence. In this study, we chose an elegant model of cerebellar neuropathology, Atoh1-En1/2 CKO, where mutant animals have conditional loss of the developmental patterning gene Engrailed 1/2 in rhombic lip-lineage neurons and exhibit a proportional scaling-down of neuron number in hypoplastic lobules of the CRB. We utilized whole-body unrestrained plethysmography …

The Tumor Microenvironment Regulates Retinoblastoma Cell Survival, Zachary K. Goldsmith

Theses and Dissertations (ETD)

Retinoblastoma (Rb) is the most common intraocular malignancy in children comprising 4% of all pediatric tumors. Early intervention increases survival rates up to 95% in developed countries; being survival rates associated to socio-economic status. Despite the high survival rates in developed countries, preservation of the eye and vision are continuing challenges in the management of Rb. Vitreous seeds constitute the greatest challenge in treatment of Rb. The unique location of these seeds within the vitreous makes them difficult to treat. Viable seeds showed reduced proliferative capacity and metabolism. making the majority refractory to current chemotherapeutics. This prompted the development of …

The Role Of Bip Co-Chaperone Sil1 In Marinesco-Sjögren Syndrome Pathogenesis, Viraj Paresh Ichhaporia

Theses and Dissertations (ETD)

Marinesco-Sjögren syndrome (MSS) is a rare, autosomal recessive, multisystem disorder, which is characterized by cerebellar ataxia, early-onset bilateral cataracts, and progressive myopathy amongst other symptoms. MSS has been attributed to mutations in the SIL1 gene, which encodes a nucleotide exchange factor for the endoplasmicreticulum- resident Hsp70 chaperone, BiP. To date, there are 46 MSS-associated mutations that have been reported in SIL1, which occur throughout this gene and are predicted to result in a loss of SIL1’s function. The large majority of these mutations cause deletions of large fractions of the SIL1 protein. Nine MSS-associated mutations are particularly interesting because they …

Signaling Induced By Inflammatory Mediators In The Rodent Pulmonary Microvasculature, Rachel Escue Helms

Theses and Dissertations (ETD)

Acute lung inflammation (ALI), stemming from a disproportionate and detrimental immune response, may arise from or complicate other disease states, leading to the often-fatal acute respiratory distress syndrome (ARDS). Because of the many culpable factors and differing points of induction, pinning down the signaling mechanisms involved in the morbidity of this disorder as well as defining an effective treatment has proved problematic. However, the most detrimental characteristic of this condition is seen regardless of the development of the response: increased microvascular permeability. Because of the architecture and the size of the pulmonary microvascular network, the lungs have a resident, sequestered …