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Multilevel Deregulation Of Survival Mechanisms In Npm-Alk+ T-Cell Lymphoma, Deeksha Vishwamitra

Dissertations and Theses (Open Access)

The anaplastic lymphoma kinase (ALK) is a single chain transmembrane receptor tyrosine kinase that belongs to the insulin receptor superfamily. Other members of this superfamily include the insulin receptor (IR), type I insulin-like growth factor receptor (IGF-IR), and the leukocyte tyrosine kinase. The common structural finding among these tyrosine kinases is the YXXXYY motif present within their respective tyrosine kinase domains. Binding of its ligands causes ALK receptor homodimerization and protein kinase activation. ALK has been previously shown to play a significant role during early developmental stages. In human embryos, the expression of ALK is mainly seen in …

Serum Omentin As A Potential Biomarker For Complex Atypical Hyperplasia And Endometrioid Endometrial Adenocarcinoma, Laura L. Holman Md

Dissertations and Theses (Open Access)

Obesity is a significant risk factor for endometrial cancer, the most common gynecologic malignancy in the United States, but much remains unclear about the relationship between obesity-related factors and the development of endometrial cancer. Omentin, a recently discovered adipokine, has been shown to be present in lower levels in patients who are obese and/or insulin resistant. A case-control study was conducted using the serum of 140 women with endometrial cancer and 75 women with endometrial hyperplasia who were matched 1:1 based on body mass index (BMI) and menopausal status to women with no history of endometrial cancer (controls). The concentration …

Cancer Incidence In First And Second Degree Relatives Of Brca1 And Brca2 Mutation Carriers, Haley Streff

Dissertations and Theses (Open Access)

Mutations in the BRCA1 or BRCA2 genes are associated with increased risks for breast, ovarian, and several other cancers. The purpose of this study was to evaluate the incidence of cancers in first and second degree relatives of BRCA mutation carriers compared to the general population. A total of 1086 pedigrees of BRCA mutation carriers were obtained from a prospectively maintained, internal review board approved study of persons referred for clinical genetic counseling at The University of Texas MD Anderson Cancer Center. We identified 9032 first and second degree relatives from 784 pedigrees which demonstrated a clear indication of parental …

Obstetrician And Gynecologist Utilization Of The Nipt Expanded Testing Option, Sarah Mayes Ba

Dissertations and Theses (Open Access)

Noninvasive prenatal testing (NIPT) enables the detection of common fetal aneuploidies such as trisomy 21, trisomy 18, trisomy 13, and sex chromosome abnormalities via analysis of cell-free fetal DNA circulating in maternal serum. Although the accuracy of NIPT for fetal aneuploidy is expected to be higher than that of currently available alternative maternal serum screening options, the implications of results are not straight forward. In October 2013, the option to screen for additional trisomies and select microdeletion syndromes, such as 22q11.2 deletion syndrome and 5 p- syndrome, became clinically available. Due to this rapidly evolving prenatal screening technology, clinicians must …

Two-Color Fluorescent Analysis Of Connexin 36 Turnover And Trafficking – Relationship To Functional Plasticity, Yanran Wang

Dissertations and Theses (Open Access)

Gap junctions (GJ) formed of Cx36 show tremendous functional plasticity on several time scales. Changes in connexin phosphorylation modify coupling in minutes through an order of magnitude, but recent studies also imply involvement of connexin turnover in regulating cell-cell communication. We utilized Cx36 with an internal HaloTag to study Cx36 turnover and trafficking in cultured cells to discriminate newly formed and pre-existing Cx36. New Cx36 in cargo vesicles was added directly to existing gap junctions and newly made Cx36 was not confined to points of addition, but diffused throughout existing gap junctions. Existing connexins also diffused into photobleached areas with …

Investigation Of Genetic Alterations In Emt Suppressor, Dear1, Through Pan-Cancer Analysis And Ultra-Deep Targeted Sequencing In Ductal Carcinoma In Situ, Jacquelyn Reuther

Dissertations and Theses (Open Access)

Ductal carcinoma in situ (DCIS) is thought to be one of the earliest pre-invasive form of and non-obligate precursor to invasive ductal carcinoma (IDC). There is an urgent need to identify predictive and prognostic biomarkers for breast cancers with a heightened risk of progression from DCIS to IDC. Our laboratory has previously discovered a novel TRIM family member, DEAR1 (Ductal Epithelium Associated Ring Chromosome 1, annotated as TRIM62) within chromosome 1p35.1, that is mutated and homozygously deleted in breast cancer and whose expression is downregulated/lost in DCIS. Previous work has shown that DEAR1 is a novel tumor suppressor …

Igfbp2 Potentiates Egfr-Stat3 Signaling In Glioma, Yingxuan Chua

Dissertations and Theses (Open Access)

Gliomas are clinically challenging brain tumors with dismal survival rates due to its infiltrative nature and ineffective standard therapy. Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the contributions of intracellular IGFBP2 to tumor development and progression are poorly understood. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of EGFR, which subsequently activates STAT3 signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via …

Genetics Of Obesity In Starr County, Texas Mexican Americans, Heather M. Highland

Dissertations and Theses (Open Access)

Currently, over two-thirds of Americans are classified as over-weight or obese. Obesity increases risk for many other diseases including type 2 diabetes, heart disease, stroke, and cancer, making obesity the largest public health problem in America and most other Westernized nations. Hispanics have a higher rate of both obesity and type 2 diabetes, making them a particularly interesting population in which to study obesity. For the last 33 years, the Starr County Health Studies has collected an array of phenotypes and biological samples from residents of Starr County, along Texas-Mexico border. This study includes 825 subjects who were not known …

The Effect Of Activation Induced Cytidine Deaminase Phosphorylation And Herpes Virus Uracil Dna Glycosylase On Antibody Diversification, Marc Macaluso

Dissertations and Theses (Open Access)

Activation-induced cytidine deaminase (AID) is a mutagenic enzyme that is expressed in mammalian B-cells and initiates the antibody diversification processes of somatic hypermuntation (SHM) and isotype class switch recombination (CSR). AID is targeted to the immunoglobulin gene locus where it deaminates cytosines to generate uracil residues in DNA. This generates guanine-uracil (U:G) mismatch lesion which are recognized by uracil DNA glycosylase (UNG), a DNA repair enzyme that removes uracil from DNA and triggers downstream repair of the lesion. While UNG is a ubiquitously expressed DNA repair enzyme, its recognition and removal of AID introduced uracils is essential in both SHM …

Investigation Of The Role Of The Scaffold Protein Shc In Erk Signaling, Kin Man Suen

Dissertations and Theses (Open Access)

Cells respond to environmental changes by converting extracellular signals into intracellular events. Scaffolding proteins play important roles in generating specificity in intracellular signaling through the combinatorial use of protein domains and posttranslational modifications. Using the scaffold Shc (Src-homology collagen-like) as a model system, we explored novel mechanisms whereby this class of protein shapes signaling output. In the present work, we focused on the role of Shc in the MAP kinase Erk signaling both prior to and post-growth factor stimulation. Prior to growth factor stimulation, we found Erk to be a direct interacting partner of Shc. The two proteins associate through …

Src Homology 2 Domain-Containing 5’-Inositol Phosphatase-2 (Ship2) Is An Effector Of Lymphatic Dysfunction, Germaine D. Agollah

Dissertations and Theses (Open Access)

The lymphatic system is essential for the transport of excess fluid, protein, and foreign materials from interstitial tissues to lymph nodes; for immune surveillance, and to maintain fluid homeostasis. Dysregulated lymphatics can be attributed to pathological conditions including tumor metastasis, inflammation, chronic wounds, obesity, blood vascular disorders, and lymphedema. Of these, lymphedema is the most extreme of lymphatic disorders and is represented by a spectrum of symptoms ranging from mild, subtle presentation to severe, disfiguring, overt presentation. Lymphedema is more manageable in the early stages of disease but severely reduces quality of life with progression. Due to lack of molecular …

Characterization Of The Roles Of Carma3 And Bcl10 In Virus-Triggered Rig-I/Mavs Signaling Pathway, Zhicheng Zhou Mr

Dissertations and Theses (Open Access)

After RNA virus infection, the innate immunity utilizes RIG-I family of receptors in the cytoplasm to initiate the production of type-I IFNs and proinflammatory cytokines by mitochondrial protein MAVS, which forms a prion-like structure to recruit TBK1and IKK complex to activate IRF3 and NF-κB, respectively. Herein, we revealed the important roles of CARMA3 and BCL10 in RIG-I/MAVS signaling pathway for the first time. CARMA3 or BCL10 deficient cells exhibited partially defective NF-κB activation but hyperactivation of TBK1-IRF3 signaling pathway upon ssRNA virus infection. It led to less production of IL6 but more production of type I IFNs and resulted in …

Targeting An Ancient Retrovirus During Melanoma Using Adoptive T Cells Therapy, Janani Krishnamurthy

Dissertations and Theses (Open Access)

Patients with metastatic melanoma have a poor prognosis due to resistance to conventional therapies. Thus, new targeted treatment strategies are required to improve therapeutic outcome. One prospective approach is to infuse T cells that are rendered specific for tumor-associated antigens (TAAs) preferentially expressed on melanoma cells. Recognition of cell-surface TAAs independent of major histocompatibility complex can be achieved by introducing a TAA-specific chimeric antigen receptor (CAR) on T cells using gene therapy. This approach is being used in clinical trials to adoptively transfer CD19-specific CAR⁺ T cells in patients with B-lineage malignancies. To generate T-cell therapy for melanoma we …

Nfat1 Contributes To Melanoma Tumor Growth And Metastasis By Regulating Il-8 And Mmp-3, Einav Shoshan

Dissertations and Theses (Open Access)

Studies from our laboratory have recently demonstrated that Gal-3 regulates autotaxin through NFAT1 and support melanoma progression. These findings prompted us to further study the role of NFAT1 in melanoma progression and metastasis. NFAT1 is a transcription factor that was first identified in immune cells, acting as a positive regulator of interleukin-2 by binding to its promoter during T cell activation. NFAT1 has an important role in the innate and adaptive immune response. In this dissertation I studied the mechanisms by which NFAT1 contributes to the acquisition of the melanoma metastatic phenotype.

To identify the role of NFAT1 in melanoma …

Elucidating The Role Of Rumi And O-Glucosylation In The Drosophila Eye, Amanda Haltom

Dissertations and Theses (Open Access)

Rumi is a protein O-glucosyltransferase that adds the sugar O-glucose onto the serine in the target sequence C-S-X-S-(P/A)-C found within properly folded EGF repeats. It was first discovered to modify the Drosophila Notch extracellular domain and to be required for Notch signaling in a temperature dependent manner, but other targets of Rumi remained unknown. Several other proteins in the Drosophila proteome harbor multiple consensus sequence highly predictive of O-glucose, including the transmembrane protein Crumbs and the secreted protein Eyes shut (Eys). Both of these proteins are required for proper eye development and mutations in their human homologs …

Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh

Dissertations and Theses (Open Access)

In mammalian cells, DNA polymerase θ (POLQ) is an unusual specialized DNA polymerase whose in vivo function is under active investigation. The protein is comprised of an N-terminal helicase-like domain, a C-terminal DNA polymerase domain, and a large central domain that spans between the two. This arrangement is also found in the Drosophila Mus308 protein, which helps confer resistance to DNA interstrand crosslinking agents. Homologs of POLQ and Mus308 are found in eukaryotes, including plants, but a comparison of phenotypes suggests that not all of these genes are functional orthologs. Flies with defective Mus308 are sensitive to DNA interstrand crosslinking …

Cancer Associated Fibroblast Derived Angiogenic Factor Mfap5 In Ovarian Cancer Progression, Sze Lee Cecilia Leung

Dissertations and Theses (Open Access)

Advanced stage ovarian cancer is the most lethal gynecologic malignancy. No major improvement on patient survival has been achieved in the past decade. Therefore, identification of predictive or prognostic markers and further understanding of the molecular mechanisms in ovarian cancer progression are of paramount importance.

While cancer cells have always been the targets for the identification of prognostic and predictive markers, the potential for developing new diagnosis and treatments based on the tumor supporting stromal microenvironment is relatively unexplored. Using transcriptome profiling analysis on microdissected stromal and epithelial components of normal and malignant ovarian tissues, we identified a gene signature …

Synthetic Lethality Of Cdk Inhibition And Doxorubicin In Triple-Negative Breast Cancer Requires P53 Inactivation, Natalie A. Jabbour-Leung

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) is an aggressive malignancy in which the tumors lack expression of estrogen receptor, progesterone receptor and HER2. As such, TNBC patients cannot benefit from clinically available targeted therapies and must rely on chemotherapy and surgery for treatment. While initially responding well to chemotherapy, TNBC patients are at increased risk of developing distant metastasis and have decreased overall survival compared to non-TNBC patients. A majority of TNBC tumors carry p53 mutations, enabling them to bypass the G1 checkpoint and complete the cell cycle even in the presence of DNA damage. Therefore, we hypothesized that TNBC cells are …

Sunitinib-Induced Cardiotoxicity Exposes Microvascular And Metabolic Derangements In The Failing Heart, Meredith R. Rodriguez

Dissertations and Theses (Open Access)

Cardiac dysfunction is one of the largest obstacles to effective cancer treatment. Not only do a growing number of cancer patients have significant cardiovascular risk factors at the time of diagnosis, but a number of targeted therapies can themselves cause cardiac dysfunction. These newer treatment options are also increasingly effective, placing a growing emphasis on post-cancer quality of life. In some instances, a patient may outlive his or her cancer only to succumb to heart failure in as little as five years. One such targeted therapy is the small molecular receptor tyrosine kinase sunitinib. Sunitinib was developed in the early …

Influx And Efflux Of Adenine Nucleotides From Erythrocytes Regulate Oxygen Transport And Systemic Metabolism, William G. O'Brien Iii

Dissertations and Theses (Open Access)

Erythrocytes are responsible for ensuring a sufficient supply of oxygen to meet activity demands. The mammalian erythrocytes primarily modulate their oxygen-carrying capacity by varying the levels of organic phosphates, such as 2,3-BPG. In other organisms, such as fish, ATP instead of 2,3-BPG is used to modulate their erythrocyte’s oxygen binding ability. Here, using a series of genetically modified mice, we investigated a previously unrecognized pathway of adenine nucleotide influx and efflux that modulates erythrocyte’s oxygen binding ability and controls systemic metabolism. Our studies show that the loss of AMPD3 and CD73, two important enzymes in regulating AMP levels intra- and …

Oxidative Protein Folding Pathways In Gram-Positive Actinobacteria, Melissa E. Robinson

Dissertations and Theses (Open Access)

Disulfide bonds are important for the stability of many secreted proteins. These covalent linkages, which result from the oxidation of neighboring cysteine (Cys) residues, are often rate-limiting steps for protein folding and maturation. Disulfide bond formation is restricted to extracellular oxidizing compartments like the eukaryotic endoplasmic reticulum and Gram-negative bacterial periplasm. Protein oxidation has been well-studied in these organisms, but largely ignored in Gram-positive bacteria. Due to the absence of an outer membrane, these organisms are thought to lack compartments in which to catalyze oxidative protein folding.

This thesis reveals that Gram-positive Actinobacteria use disulfide bond formation to help fold …

Knowledge And Self-Esteem In Individuals With Neurofibromatosis Type 1 (Nf1), Kayla Vaughn

Dissertations and Theses (Open Access)

Neurofibromatosis Type 1 (NF1) is a progressive genetic disorder characterized mainly by café-au-lait macules, Lisch nodules, as well as cutaneous and subcutaneous neurofibromas among other traits. Due to the physical manifestations of the condition, it has been observed that individuals with NF1 have lower self-esteem (SE) when compared to the general population. Additionally, a study published over 20 years ago found that overall knowledge of NF1 was poor in individuals affected with the condition. The goal of our study was to reassess knowledge in this population and investigate whether it is related to SE. A survey comprised of knowledge-based questions …

Characterization Of Low Density Intracranial Lesions Using Dual-Energy Computed To Mography, Jessica L. Nute

Dissertations and Theses (Open Access)

Calcific and hemorrhagic foci of susceptibility are frequently encountered on routine brain MR studies. Both etiologies cause variations in local magnetic field strength, leading to dark regions on the MR images that cannot be classified. Single-energy CT (SECT) can be used to identify lesions with attenuation over 100 HU as calcific, however lesions with lower attenuation cannot be reliably identified. While calcific lesions are unlikely to cause harm, hemorrhagic lesions carry a risk of subsequent intracranial bleeding; as such, identification of hemorrhage is vital in preventing the inappropriate use of anticoagulant medications in patients with hemorrhagic lesions.

Given there currently …

Developmental Origins Of Renal Connecting Tubule And Collecting Duct: Role Of Aqp2+ Progenitor Cells, Lihe Chen

Dissertations and Theses (Open Access)

The connecting tubule interconnects the nephron and collecting duct, which arise from kidney mesenchyme and the ureteric bud, respectively, to generate the functional tubular networks. The collecting duct is comprised of principal cells and intercalated cells, which bear different molecular signatures and regulate sodium/water and acid/base balance, respectively. The progenitor cells of the connecting tubule and the collecting duct remain virtually unknown.

We generated two Aqp2 lineage tracing mouse models. In these models, Aqp2Cre transgene drives Cre expression by the Aqp2 promoter to exclusively either inactivate histone H3 K79 methyltransferase Dot1l (Dot1l^f/f Aqp2Cre) or activate RFP in …

Atp-Citrate Lyase Links Cyclin E To Cellular Metabolism In Breast Cancer, Kim Lucenay

Dissertations and Theses (Open Access)

Cyclin E is altered or overexpressed in approximately one-third of tumors from patients with invasive breast cancer and is a powerful independent predictor for survival in women with stage I-III breast cancer. Full-length cyclin E (EL) is post-translationally cleaved into two low-molecular-weight isoforms, LMW-E (T1) and LMW-E (T2). LMW-E have been shown to exhibit greater binding affinity for cyclin-dependent kinase 2 (CDK2) , cyclin dependent kinase inhibitors (CKIs), p21 and p27, but are resistant to p21 and p27 inhibition. In addition, transgenic mice expressing LMW-E have increased mammary tumor development and metastasis compared to EL transgenic mice. Therefore, LMW-E are …

Targeted Inhibition Of Pi3k, Mtor, And Igf1r For The Treatment Of Undifferentiated Pleomorphic Sarcoma, Caitlin Denise May

Dissertations and Theses (Open Access)

Undifferentiated pleomorphic sarcoma (UPS) is an aggressive mesenchymal malignancy largely devoid of indicators for its originating tissue. Surgery remains the standard of care, as radiation therapy and systemic chemotherapy have limited efficacy in UPS patients with localized and metastatic disease, respectively. Therefore, it is imperative to identify and evaluate novel therapeutic targets in UPS in order to provide more efficacious treatment options for patients. Previous studies have revealed that members of the phosphatidylinositol-3-kinase/mammalian target of rapamycin (PI3K/mTOR) signaling pathway can be used to predict patient outcome in cohorts containing patients with various subtypes of soft tissue sarcoma. Furthermore, we have …

Understanding The Role Of Sumoylation In Regulating Lkb1 Function, Joan W. Ritho

Dissertations and Theses (Open Access)

Energy homeostasis in a cell is critical for its survival during metabolic stress. Liver kinase B1 (LKB1), one of the key regulators of cellular energy balance, was initially discovered as a tumor suppressor mutated in patients with Peutz-Jeghers syndrome. Germline mutations in LKB1 predispose patients to develop several benign and malignant tumors including gastrointestinal and lung cancers. In 2003, several groups demonstrated that LKB1is a major upstream kinase of the energy sensor AMP-activated protein kinase (AMPK), directly associating it with the regulation of energy balance in cells. During energy stress, LKB1 phosphorylates AMPK at threonine 172 (T172) resulting in AMPK …

Texas Physicians' Awareness And Utilization Of Genetic Services, Callie L. Jenevein

Dissertations and Theses (Open Access)

The number of disorders for which genetic testing is available has increased nearly 500% in the past 15 years. Access to the majority of genetic tests and services hinges on physicians’ ability to identify patients at risk for genetic disease and provide appropriate testing and counseling or refer to genetic specialists. Recent research demonstrates the need for referrals to genetic specialists by showing that many physicians lack skills required to perform appropriate genetic services, such as making proper risk assessments, providing genetic counseling, ordering genetic testing and interpreting results. However, little research exists on physicians’ awareness and utilization of genetic …

The Role Of Autophagy In The Sensitivity Of Osteosarcoma Cells To Gemcitabine Treatment, Janice M. Santiago-O'Farrill

Dissertations and Theses (Open Access)

Despite treatment improvement for osteosarcoma (OS), overall survival has remained unchanged in the last 20 years. Pulmonary metastasis continues to be the main cause of death; novel therapeutic strategies are urgently needed to improve the survival rate of these patients. Previous data in our laboratory has demonstrated that aerosol gemcitabine (GCB) treatment has a significant therapeutic effect on metastatic OS. However, treatment efficacy is decreased due to acquired resistance by a population of tumor cells that fails to respond to treatment. Recent studies have implicated autophagy as a resistance mechanism in various types of cancer. The purpose of this study …

The Structural Mechanism Of Allosteric Modulation Of The Nmda Receptor: A Balance Of Tensions, Rita E. Sirrieh

Dissertations and Theses (Open Access)

N-methyl-D-aspartate (NMDA) receptors are one of the three main types of ionotropic glutamate receptors in the central nervous system. NMDA receptors mediate the rapid excitatory neurotransmission that underlies learning and memory formation. Conversely, NMDA receptors are implicated in a variety of neurological disorders. Studies targeting the mechanism of allosteric modulation, such as this study, hope to contribute to the understanding of how NMDA receptors are modulated to allow for better drug development.

NMDA receptors are obligate heterotetramers, typically composed of glycine-binding GluN1 subunits and glutamate-binding GluN2 subunits. The GluN2 subunits can be one of four subtypes (A-D). Each subunit is …