Medicine and Health Sciences Commons^™

Patient Attitudes To Ward Genetic Testing For Inherited Predispositions To Hematologic Malignancies, Taylor Beecroft

Dissertations and Theses (Open Access)

Although inherited predispositions to hematologic malignancies have previously been considered extremely rare, approximately 12 causative genes have been implicated in the last decade. Since individuals diagnosed with leukemia have not historically been considered for evaluation of inherited predispositions, genetic testing is underperformed in this population. This study used focus group discussions to explore the attitudes, motivations, and barriers to genetic testing for 23 patients with leukemia. Participants generally exhibited a positive regard for the utility of genetic testing, and were primarily motivated by concern for their family and a sense of altruism toward all leukemia patients. While drawbacks and barriers …

Investigating Invasion In Ductal Carcinoma In Situ With To Pographical Single Cell Genome Sequencing, Anna Casasent, Anna Casasent

Dissertations and Theses (Open Access)

Synchronous Ductal Carcinoma in situ (DCIS-IDC) is an early stage breast cancer invasion in which it is possible to delineate genomic evolution during invasion because of the presence of both in situ and invasive regions within the same sample. While laser capture microdissection studies of DCIS-IDC examined the relationship between the paired in situ (DCIS) and invasive (IDC) regions, these studies were either confounded by bulk tissue or limited to a small set of genes or markers. To overcome these challenges, we developed Topographic Single Cell Sequencing (TSCS), which combines laser-catapulting with single cell DNA sequencing to measure genomic copy …

Current Genetic Counseling Practice Following Positive Non-Invasive Prenatal Testing For Sex Chromosome Abnormalities, Lauren Fleddermann

Dissertations and Theses (Open Access)

The purpose of this study was to describe current prenatal and pediatric genetic counseling practice following a non-invasive prenatal testing (NIPT) result positive for a sex chromosome abnormality (SCA). The positive predictive value for SCA with NIPT is lower than seen for Trisomy 21 due to natural loss of the X chromosome from maternal cells during aging, confined placental mosaicism, and undiagnosed maternal sex chromosome abnormality. Except for 45,X, individuals with SCA usually have no ultrasound or postnatal findings. This makes follow-up for unresolved positive NIPT necessary; however, there are currently no clinical guidelines. This study used a prospective anonymous …

Functional Heterogeneity Of Fibroblasts In Dermal Wound Healing, Ehsan Ehsanipour

Dissertations and Theses (Open Access)

Impaired wound healing can lead to excessive scarring, dehiscence, chronic ulcers, and infection, which have adverse impact on the quality of life and pose a significant economic burden on the health care system. Thus, new therapeutic approaches are critically important. Dermal fibroblasts are critical players in cutaneous wound healing, possibly lending their contractile properties and extracellular matrix (ECM) remodeling functions to promote effective tissue repair. Dermal fibroblasts are also postulated to orchestrate tissue repair by interacting with and controlling other cell types in the wound microenvironment. It has become increasingly clear that the generic term “fibroblast” encompasses a diverse cell …

The Epithelial To Mesenchymal Transition In Breast Cancer Induces Alterations In Metabolism, Esmeralda Ramirez-Peña

Dissertations and Theses (Open Access)

Metastasis is currently incurable. Recent studies suggest that metabolic reprogramming significantly impacts metastatic progression. Understanding the underlying biology of how metabolic reprogramming influences metastasis will shed light on developing novel ways to treat metastasis and is of urgent clinical need. A potent mediator of metastatic potential in breast cancer is the winged helix/Forkhead domain transcription factor FOXC2. We have previously shown that FOXC2 is necessary and sufficient to promote metastasis through induction of the epithelial to mesenchymal transition (EMT). EMT is a latent embryonic program that is aberrantly induced in breast cancer cells conferring migratory and invasive capabilities in addition …

Epithelial To Mesenchymal Transition As A Predictor Of Response To Polo-Like Kinase 1 Inhibition-Induced Apoptosis In Non-Small Cell Lung Carcinoma, Pavitra Viswanath

Dissertations and Theses (Open Access)

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. Outcomes are poor for patients with recurrent, advanced or metastatic NSCLC. Polo-like kinase 1 (PLK1), involved in the regulation of mitotic processes and the response to DNA damage, is overexpressed in NSCLC. Inhibiting PLK1 may be an effective treatment for NSCLC patients as it is involved in the mechanisms of resistance to several chemotherapy drugs. PLK1 inhibition or knock-down has various effects in cancer cells, including mitotic arrest, apoptosis, and senescence. Predictive biomarkers have not been identified to select those patients who are likely to respond to …

Investigating The Impact Of Intragenic Dna Methylation On Gene Expression, And The Clinical Implications On Tumor Cells And Associated Stroma, Michael Mcguire

Dissertations and Theses (Open Access)

Investigations into the function of non-promoter DNA methylation have yielded new insights into epigenetic regulation of gene expression. Previous studies have highlighted the importance of distinguishing between DNA methylation in discrete functional regions; however, integrated non-promoter DNA methylation and gene expression analyses across a wide number of tumor types and corresponding normal tissues have not been performed. Through integrated analysis of gene expression and DNA methylation profiles, we uncovered an enrichment of DNA methylation sites within the gene body and 3’UTR in which DNA methylation is strongly positively correlated with gene expression. We examined 32 tumor types and identified 57 …

Development And Characterization Of A Bi-Specific Antibody Targeting Hla-A2/Pr1, Amanda Herrmann

Dissertations and Theses (Open Access)

Despite substantial advances in the treatment of acute myeloid leukemia (AML), only 30% of AML patients survive more than 5 years. Therefore, new therapeutics are much needed. Here, we present novel therapeutic strategy targeting myeloid leukemia antigen, HLA-A2 restricted peptide PR1.Previously, we have conducted pre-clinical development and humanization of a T cell receptor-like monoclonal antibody (h8F4) that targets PR1/HLA-A2 and eliminates AML xenografts by antibody-dependent cellular cytotoxicity (ADCC) following repeat dosing. To improve the potency of h8F4, we have developed a bi-specific T cell-engaging antibody that targets PR1/HLA-A2 on leukemia and CD3 on neighboring T cells. Here we demonstrate successful …

Nanoscale Organization Of The Small Gtpase Rac1, Kelsey Maxwell

Dissertations and Theses (Open Access)

Rac1 is a small, guanine-nucleotide binding protein that cycles between an inactive GDP-bound and active GTP-bound state to regulate actin-mediated motility, migration, and adhesion. Plasma membrane (PM) localization is essential for its biological activity. Rac1 PM targeting is directed by a C-terminal membrane anchor that encompasses a geranylgeranyl-cysteine-methyl-ester, palmitoyl, and a polybasic domain (PBD) of contiguous lysine and arginine residues. Using high-resolution imaging combined with spatial mapping analysis, I found that Rac1 forms nanoclusters on the PM. Cycling between the GTP- and GDP-bound states, Rac1 forms nanoclusters that are non-overlapping, consequently undergoing guanine nucleotide-dependent spatial segregation. I further found that …

Examining The Relationship Between Genetic Counselors’ Implicit Attitudes To Ward Disability And Their Practice Methods, Helen W. Gould

Dissertations and Theses (Open Access)

Genetic counselors serve as a link between the medical community and the disability community as they are regularly the first exposure families have following a new diagnosis in a pregnancy, infant or child. This role requires genetic counselors to be responsible and compassionate when approaching conversations about disability. With a lack of research on how the specific attitudes of genetic counselors toward disability impact clinical practice, we aimed to understand these attitudes, what factors affect implicit attitudes toward disability, and how these attitudes affect counseling. Case scenarios involving disability were used to examine different counseling content preferences within a genetic …

Genetic Testing Practices Of Genetic Counselors, Geneticists, And Pediatric Neurologists With Regard To Childhood-Onset Neurogenetic Conditions, Sara Wofford

Dissertations and Theses (Open Access)

Identifying genetic diagnoses for neurological conditions with a considerable hereditary component, such as autism spectrum disorder (ASD), intellectual disability, and epilepsy, is critical to providing proper medical management for these patients and their families. However, many patients with these conditions are not tested appropriately or receive no genetic testing at all. The current study was designed to characterize the genetic testing practices of the providers most likely to evaluate or order genetic testing for these patients: pediatric neurologists, geneticists, and genetic counselors. The study noted significant variance between the testing strategies selected by pediatric neurologists compared to those of geneticists …

Outcomes Of Genetic Testing In A Genitourinary Genetics Clinic, Annelise Pace

Dissertations and Theses (Open Access)

Several known hereditary cancer syndromes confer an increased risk for genitourinary (GU)related malignancies. Various guidelines indicate when to refer patients to genetic counseling for GU-related hereditary cancer syndromes but there is limited research on the clinical picture of these patients, including their cancerous and non-cancerous features, the genetic testing strategy for this population, and the probability of having a positive germline mutation if testing is performed. The purpose of this study is to determine the most common indications for ordering genetic testing in a GU Genetics Clinic and evaluate whether there is a relationship between the indication for genetic testing …

Identification Of Tissue And Circulating Biomarkers For Premalignant And Malignant Lesions, Shu-Hong Lin

Dissertations and Theses (Open Access)

Recent advancement in technologies including next-generation sequencing and production-scale throughput qPCR have revolutionized the identification of biomarkers in the epidemiology field. In response to the vast amount of data generated from high-throughput technologies, novel inventions in the computer sciences fields have been applied to analyze these data. The current study demonstrates the application of such technologies in a variety of scenarios.

I first described how targeted and whole-exome sequencing were used to identify somatic mutations which marked the differences between colorectal adenomas and adenocarcinomas. A statistical test based on the unique clustering pattern of tumor suppressor genes and oncogenes was …

Computational Insights Into The Generation Of Chromosomal Copy Number Changes, Yihua Liu

Dissertations and Theses (Open Access)

Deviations from a diploid configuration of the human genome, spanning single genes or entire chromosomes, can have wide-ranging impacts on the variation of human phenotypes, including Mendelian and complex forms of diseases. These chromosomal alterations — such as duplications, deletions or copy-neutral loss-of-heterozygosity — are thus important forms of genetic variation for phenotyping populations of individuals as well as populations of cells. Indeed, copy number variants (CNVs) serve as hallmarks of critical changes in the development of particular diseases such as cancer and thus may be used as biomarkers. These CNVs may be either inherited (transmitted by germ cells, originating …

Tumor Immunotherapy: Mechanisms Of Acquired Resistance And Characterization Of Immune Related To Xicities, Ashvin Jaiswal

Dissertations and Theses (Open Access)

Tumor immunotherapy has shown very promising clinical benefit across an array of cancers; however, two major challenges remain unresolved in the field. First, many patients do not respond to therapy at all or relapse after a period of remission. Second, there are often dose-limiting immune related adverse effects associated with immunomodulation.

In order to understand the mechanisms employed by tumors to evade immunotherapeutic responses, we established a murine model of melanoma designed to elucidate the molecular mechanisms underlying immunotherapy resistance. Through multiple in vivo passages, we selected a B16 melanoma tumor line that evolved complete resistance to combination blockade of …

Identifying Subunit Organization And Function Of The Nuclear Rna Exosome Machinery, Jillian Losh

Dissertations and Theses (Open Access)

IDENTIFYING SUBUNIT ORGANIZATION AND FUNCTION OF THE NUCLEAR RNA EXOSOME MACHINERY

Jillian Strother Losh, A.S., B.S.

The eukaryotic RNA exosome processes and degrades many classes of RNA. It is present in the nucleus and the cytoplasm, highly evolutionarily conserved, and essential for viability. Since the RNA exosome is such a significant component of the RNA degradation machinery, it is unsurprising that even single point mutations in a few of its subunits have been linked to human disease. For example, at least eight point mutations in a single subunit of the RNA exosome have been linked to pontocerebellar hypoplasia subtype 1b …

Sphingosine Kinase 1 Regulates Fascin Expression To Promote Metastasis In Triple Negative Breast Cancer, Sunil Acharya

Dissertations and Theses (Open Access)

Distant metastasis is the primary cause of breast cancer–related mortality. To date, effective therapeutic drugs that target metastasis are still lacking. Triple negative breast cancer (TNBC) occurs in high frequency in young women and are more likely to recur and metastasize than are other breast cancer subtypes. Also, TNBC patients cannot benefit from currently available hormonal or targeted therapies, as they lack estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. Thus, understanding the signaling pathways that promote TNBC metastasis and developing novel therapeutic approaches to target them are critical, in order to prolong the survival and improve …

Genomic Evolution Of Chemoresistance In Triple-Negative Breast Cancer Delineated By Single Cell Sequencing, Charissa Kim

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) is an aggressive subtype that displays extensive intratumor heterogeneity and frequently (46%) develops resistance to neoadjuvant chemotherapy (NAC). Currently, the genomic basis of chemoresistance remains poorly understood. An important question is whether resistance to chemotherapy is driven by the selection of rare pre-existing subclones with genomic mutations and transcriptional programs that confer resistance to chemotherapy (adaptive resistance) or by the spontaneous induction of new mutations and expression changes that confer a resistant phenotype (acquired resistance). To investigate this question we applied single cell DNA and RNA sequencing methods and deep-exome sequencing to longitudinal time-point samples collected …

Somatostatin Receptor 2 Regulation By C-Terminal Motifs And Pdz Domain Proteins, Courtney Olsen

Dissertations and Theses (Open Access)

Somatostatin receptor 2 (sst2) is a Gi-coupled G-protein coupled receptor that mediates many of somatostatin’s neuroendocrine actions. Sst2 is a clinically important GPCR as it is the drug target of somatostatin analogs such as octreotide, lanreotide, and pasireotide. Treatment with these agonists is the main medical approach to controlling excessive hormone secretion from neuroendocrine tumors. Activation of sst2 decreases hormone secretion by inhibiting cAMP production and decreasing intracellular calcium concentrations. In addition, treatment with somatostatin analogs has been shown to decrease tumor growth. Unfortunately, many patients will fail to respond to somatostatin analogs despite sst2 being present on their tumors. …

Bayesian Designs For Early Phase Clinical Trials With Novel Target Agents, Heng Zhou

Dissertations and Theses (Open Access)

My dissertation mainly focus on Bayesian designs for early phase clinical trials with novel target agents. It includes three specific topics: (1) reviewing novel phase I clinical trial designs and comparing their operating characteristics; (2) Proposing a Bayesian optimal phase II clinical trial (BOP2) design with simple and complex endpoints under a unified framework; and (3) extending the BOP2 design to incorporate the durable clinical response as a primary endpoint.

A number of novel model-based and model-assisted designs have been proposed to find the maximum tolerated dose (MTD) in phase I clinical trials, but their differences and relative pros and …

Identifying Molecular Targets And Validating Novel Therapies For Ovarian Cancer, Alejandro Villar-Prados

Dissertations and Theses (Open Access)

Re-purposing of targeted therapies for additional tumor types is a promising avenue for expanding treatment options for cancer patients, however accurately predicting what re-purposed targeted therapy will be effective remains challenging. To address this need, we developed a Therapy Predicting Tool (TPT) that accurately predicts the beneficial therapeutic effect of clinically relevant targeted therapies and the downstream pathways they may impact in the cancer of interest. Using ovarian cancer as a model to biologically validate our tool, we determined that Bromodomain and Extra-Terminal motif inhibitors (BETis), which target proteins such as BRD4, held the greatest promise to produce therapeutic effects …

Trim24 As An Oncogene In The Mammary Gland, Aundrietta Duncan

Dissertations and Theses (Open Access)

Despite the many advances made in breast cancer research and treatments, breast cancer remains one of the deadliest diseases plaguing women worldwide. While many findings on genetic mutations and their role in predisposing people to breast cancer have been uncovered, we are just beginning to understand the extent to which epigenetic regulators promote tumorigenic phenotypes, metastasis, and chemotherapeutic resistance. Moreover, new experimental tools offer the ability to address questions we were previously unable to assess. My project takes advantage of a new mouse model to understand the role of a proto-oncogenic, transcriptional co-regulator, TRIM24, in mammary gland development and disease. …

The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations and Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …

Development Of 3d-Printed Patient Specific Bolus For Clinical Use In To Tal Scalp Irradiation, Garrett Baltz

Dissertations and Theses (Open Access)

Total scalp irradiation (TSI) is a specialized radiation therapy technique that aims to deliver a uniform dose to the entire scalp. Original electron-based TSI techniques had limited homogeneity due to hot and cold spots created at field junctions due to the multiple matched fields that were required to treat the entire scalp. The transition to photon volumetric-modulated arc therapy based TSI techniques has improved homogeneity, to the point where non-conformal bolus is now a limiting factor. Bolus is required to build-up full dose to the scalp surface in total scalp irradiation. Creating bolus that is conformal to the scalp is …

Uncertainty In Illness And Health Literacy In Pancreatic Cancer Patients, Rae Reynolds

Dissertations and Theses (Open Access)

Background: Despite a shared link to cognitive processing of health information suggested by their definitions, information on the association between uncertainty and health literacy is scarce. Their relationship has not been studied in pancreatic cancer patients.

Aims: To evaluate uncertainty and health literacy in pancreatic cancer patients, examine their bivariate correlation, and determine significant predictors.

Methods: This descriptive, cross-sectional study was conducted in a comprehensive cancer center. Uncertainty was measured using the Mishel Uncertainty in Illness Scale -Community and health literacy was measured using the Cancer Health Literacy Test 30. Spearman’s rho tested correlation and linear regression models were …

Discovery And Effects Of Pharmacological Inhibition Of The E3 Ligase Skp2 By Small Molecule Protein-Protein Interaction Disruptors, John K. Morrow

Dissertations and Theses (Open Access)

Skp2 (S-phase kinase-associated protein 2), one component of the SCF E3 ubiquitin ligase complex, directly interacts with Skp1 and indirectly associates with Cullin1 and Rbx1 to bridge the E2 conjugating enzyme with its protein substrate to execute its E3 ligase activity. Skp2 is an Fbox protein (due to it containing an Fbox domain) and it is the rate-limiting component of the SCF complex. Skp2 targets several cell-cycle regulatory proteins for ubiquitination and degradation; most notable and significant for cancer are the cyclin-dependent kinase inhibitor, p27. Skp2 is an oncogene and studies have shown that over-expression of Skp2 leads to increased …

Characterizing The Information Needs Of Rural Healthcare Practitioners With Language Agnostic Automated Text Analysis, Melissa Resnick

Dissertations and Theses (Open Access)

Objectives – Previous research has characterized urban healthcare providers' information needs, using various qualitative methods. However, little is known about the needs of rural primary care practitioners in Brazil. Communication exchanged during tele-consultations presents a unique data source for the study of these information needs. In this study, I characterize rural healthcare providers' information needs expressed electronically, using automated methods.

Methods – I applied automated methods to categorize messages obtained from the telehealth system from two regions in Brazil. A subset of these messages, annotated with top-level categories in the DeCS terminology (the regional equivalent of MeSH), was used to …

Using The Literature To Identify Confounders, Scott Malec

Dissertations and Theses (Open Access)

Prior work in causal modeling has focused primarily on learning graph structures and parameters to model data generating processes from observational or experimental data, while the focus of the literature-based discovery paradigm was to identify novel therapeutic hypotheses in publicly available knowledge. The critical contribution of this dissertation is to refashion the literature-based discovery paradigm as a means to populate causal models with relevant covariates to abet causal inference. In particular, this dissertation describes a generalizable framework for mapping from causal propositions in the literature to subgraphs populated by instantiated variables that reflect observational data. The observational data are those …

Impact Of Terminology Mapping On Population Health Cohorts Impact, Barbara A. Berkovich

Dissertations and Theses (Open Access)

Background and Objectives: The population health care delivery model uses phenotype algorithms in the electronic health record (EHR) system to identify patient cohorts targeted for clinical interventions such as laboratory tests, and procedures. The standard terminology used to identify disease cohorts may contribute to significant variation in error rates for patient inclusion or exclusion. The United States requires EHR systems to support two diagnosis terminologies, the International Classification of Disease (ICD) and the Systematized Nomenclature of Medicine (SNOMED). Terminology mapping enables the retrieval of diagnosis data using either terminology. There are no standards of practice by which to evaluate and …

A License To Kill: Understanding Natural Killer Cell Licensing To Fight Cancer, Jolie Schafer

Dissertations and Theses (Open Access)

Natural killer (NK) cell education is an essential developmental process for NK cell effector function, that renders some NK cells “licensed” and others “unlicensed” (with heightened or lowered effector function potential, respectively) against tumor and targets lacking self-molecules. However, the underlying mechanisms responsible for the heightened effector responses of licensed cells remain unknown. Using NK cells derived from humans and expanded ex vivo we performed high-throughput protein expression analysis, and identified multiple proteins that are differentially regulated in licensed and unlicensed human NK cells before and after inhibition by killer-cell immunoglobulin-like receptors (KIRs) and activation by the NKp46 natural cytotoxicity …