Digital Commons Network^™

Deciphering The Roles Of Δnp63 In Regulating Epithelial To Mesenchymal Transition, Cancer Progression And Metastasis, Ngoc Bui

Dissertations and Theses (Open Access)

p63 is a member of the p53 family, a well-known tumor suppressor which is considered the guardian of the genome. The TP63 gene encodes multiple isoforms that can be categorized into two main isoforms, TAp63 and ΔNp63, which are expressed in different cellular compartments and have distinct functions in many biological processes. While the Flores laboratory identified TAp63 as a tumor and metastasis suppressor, the precise roles of ΔNp63 isoforms in tumorigenesis and metastasis remain elusive. ΔNp63 is the predominant p63 isoform expressed in the epidermis and plays essential roles in regulating epidermal development and homeostasis. Utilizing a ΔNp63-conditional …

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. …

Biological Clocks, Inflammation, And Multiorgan Damage In Sickle Cell Disease, Morayo Adebiyi

Dissertations and Theses (Open Access)

Sickle cell disease (SCD) is a dangerous condition caused by a genetic mutation on the human beta-globin gene that contributes to erythrocyte sickling, the hallmark of the disease. Previous metabolomics studies have confirmed that elevated sphingosine kinase 1 (SphK1) mediates sphingosine-1-phosphate (S1P) production to promote erythrocyte sickling. S1P signals via five S1P receptors (S1PR) regulates several pathophysiological functions.

In the first chapter of this dissertation, I explored the role of S1PRs in SCD by utilizing pharmacologic and genetic tools. To determine the role of S1P-S1PRs signaling in SCD, I treated humanized Berkeley sickle mice (Berkeley HBS mice), with FTY720, a …

Identification And Utility Of Dna In Exosomes, Paul Kurywchak

Dissertations and Theses (Open Access)

Cancer-associated mortality has been declining for two decades but remains a significant public health problem, especially when patients initially present with advanced disease. Early detection methods have improved survival rates but remain unavailable for a majority of cancers due to a lack of sensitive biomarkers or numerous limitations associated with current diagnosis strategies. Approaches to develop “liquid biopsies” by detecting tumor cells or DNA in the blood have led to several breakthroughs and create the potential for non-invasive, routine assessment of diseases status. However, these biomarkers are rare and currently difficult to isolate, especially in the early stages of 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 …

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 …

A Behavioral Lifestyle Intervention Enhanced With Multiple-Behavior Self-Monitoring Using Mobile And Connected Tools For Underserved Individuals With Type 2 Diabetes And Comorbid Overweight Or Obesity: Pilot Comparative Effectiveness Trial, Jing Wang, Chunyan Cai, Nikhil Padhye, Philip Orlander, Mohammad Zare

Faculty, Staff and Student Publications

BACKGROUND: Self-monitoring is a cornerstone of behavioral lifestyle interventions for obesity and type 2 diabetes mellitus. Mobile technology has the potential to improve adherence to self-monitoring and patient outcomes. However, no study has tested the use of a smartphone to facilitate self-monitoring in overweight or obese adults with type 2 diabetes mellitus living in the underserved community.

OBJECTIVE: The aim of this study was to examine the feasibility of and compare preliminary efficacy of a behavioral lifestyle intervention using smartphone- or paper-based self-monitoring of multiple behaviors on weight loss and glycemic control in a sample of overweight or obese adults …

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 …

Meta-Analysis Of The Effects Of Exercise Interventions On Obese Adolescents, Brandy E. Strahan Phd, Rn, Hyochol Ahn Phd, Ms-Ece, Ms-Cts, Aprn, Anp-Bc, Jonathan Shuster M.Sc., Ph.D.

Journal of Nursing & Interprofessional Leadership in Quality & Safety

A meta-analysis of 10 randomized control studies published in 2003-2013 was conducted to provide a summary of the effects of exercise interventions on obese adolescents. Outcomes of the reviewed trials included body mass index, weight, glucose, and triglycerides. Data were combined using an inverse variance weighted random effects model. The effect size estimate for BMI was 1.354 kg/m² (p < 0.001, SE 0.321), indicating that the BMI of individuals in treatment groups improved, as compared to control groups. A statistically significant reduction in weight was greater in the intervention groups than the control groups by 3.815 kg (p = 0.001, SE 1.101). The findings of this meta-analysis show that exercise interventions may improve control of weight and BMI and in turn be a factor in decreasing obesity.

Sexting And Mental Health: A School-Based Longitudinal Study Among Youth In Texas, Pooja Chaudhary, Melissa Peskin, Jeff R. Temple, Robert C. Addy, Elizabeth Baumler, Ross Shegog

Journal of Applied Research on Children: Informing Policy for Children at Risk

Background: Sexting has emerged as a common socio-cultural problem in our society today. Few studies have estimated the prevalence of sexting among younger middle school youth and even fewer have assessed the relationship between sexting and mental health outcomes like anxiety and depression symptoms among middle school youth.

Objectives: To estimate the prevalence of sexting among sixth and seventh-grade middle school students in a large urban school district in Southeast Texas and to assess its relationship with mental health outcomes (both anxiety and depression) among these youth.

Methods: A retrospective analysis of an existing three-year randomized, two-arm, nested longitudinal study …

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 …

Amygdala-Frontal Connectivity Predicts Internalizing Symptom Recovery Among Inpatient Adolescents, Amanda Venta, Carla Sharp, Michelle Patriquin, Ramiro Salas, Elizabeth Newlin, Kaylah Curtis, Philip Baldwin, Christopher Fowler, B Christopher Frueh

Staff and Researcher Publications

Background: The possibility of using biological measures to predict the trajectory of symptoms among adolescent psychiatric inpatients has important implications. This study aimed to examine emotion regulation ability (measured via self-report) and a hypothesized proxy in resting-state functional connectivity [RSFC] between the amygdala and frontal brain regions as baseline predictors of internalizing symptom recovery during inpatient care.

Methods: 196 adolescents (61% female; Mage = 15.20; SD = 1.48) completed the Achenbach Brief Problem Monitor (BPM) each week during their inpatient care. RSFC (n = 45) and self-report data of emotion regulation (n = 196) were collected at baseline.

Results: The …

Clinical Utility Of The Dsm-5 Alternative Model For Borderline Personality Disorder: Differential Diagnostic Accuracy Of The Bfi, Scid-Ii-Pq, And Pid-5, J Christopher Fowler, Alok Madan, Jon G Allen, Michelle Patriquin, Carla Sharp, John M Oldham, B Christopher Frueh

Staff and Researcher Publications

Background: With the publication of DSM 5 alternative model for personality disorders it is critical to assess the components of the model against evidence-based models such as the five factor model and the DSM-IV-TR categorical model. This study explored the relative clinical utility of these models in screening for borderline personality disorder (BPD).

Methods: Receiver operator characteristics and diagnostic efficiency statistics were calculated for three personality measures to ascertain the relative diagnostic efficiency of each measure. A total of 1653 adult inpatients at a specialist psychiatric hospital completed SCID-II interviews. Sample 1 (n=653) completed the SCID-II interviews, SCID-II Questionnaire (SCID-II-PQ) …

Separated Same-Sex Parents’ Experiences And Views Of Services And Service Providers, Luke Gahan

Journal of Family Strengths

Same-sex parents are compelled to be more reflective, to plan, and to negotiate their contact with mainstream service providers and professionals in an effort to find those whom they feel comfortable with disclosing their sexuality and/or to find a service provider who would adequately understand their unique needs. This paper presents findings from an Australian qualitative study of separated same-sex parents and explores their experiences with professionals and service providers during and after their separation. As a consequence of their separation, same-sex parents encountered new service providers with whom they had to navigate relationships with; this paper will focus on …

Book Review: The Remedy: Queer And Trans Voices On Health And Health Care, Krista S. Gehring

Journal of Family Strengths

The remedy: Queer and trans voices on health and health care, by Z. Sharman. Vancouver, BC: Arsenal Pulp Press 2016. 256 pp. $18.95.

Genetic Epidemiology Of Neural Tube Defects, Philip J Lupo, A J Agopian, Heidi Castillo, Jonathan Castillo, Gerald H Clayton, Nienke P Dosa, Betsy Hopson, David B Joseph, Brandon G Rocque, William O Walker, John S Wiener, Laura E Mitchell

Faculty, Staff and Student Publications

It has been estimated that 60-70% of neural tube defects (NTDs) have a genetic component, but few causative genes have been identified. The lack of information on genes associated with non-syndromic NTDs in humans is especially notable as the "genomic revolution" has led to new tools (e.g., genome-wide genotyping arrays, next-generation sequencing) that are helping to elucidate the full spectrum of genetic variation (from common to rare) contributing to complex traits, including structural birth defects. However, the application of modern genomic approaches to the study of NTDs has lagged behind that of some other common structural birth defects. This may …

Sexual Health Education For Behavior Change: How Much Is Enough?, Ross Shegog, Elizabeth Baumler, Robert C. Addy, Melissa Peskin, Melanie Ann Thiel, Susan R. Tortolero, Christine Markham

Journal of Applied Research on Children: Informing Policy for Children at Risk

Purpose: Successful implementation of sexual health curricula in school settings is often compromised by competing academic priorities. This study explores the association between exposure to sexual health lessons (time-on-task in hours and lesson content topics) and delayed sexual initiation of middle school students at long term follow-up.

Methods: Post hoc data analysis was conducted from a RCT (n=15 middle schools) in the south-central U.S. in which grade 7 students demonstrated delayed sexual initiation (adjusted odds ratio [AOR]: 1.54, 95% CI: 1.20 to 1.99) by grade 9 follow-up after using It’s Your Game (IYG), a 24 lesson sexual health curriculum. Logistic …

Native Iyg: Improving Psychosocial Protective Factors For Hiv/Sti And Teen Pregnancy Prevention Among Youth In American Indian/Alaska Native Communities, Ross Shegog Phd., Stephanie Craig Rushing Phd, Mph, Cornelia Jessen Ma, Travis L. Lane Ba, Gwenda Gorman Bs, Amanda Gaston Mat, Taija Koogei Revels Bs, Jennifer Torres Mph, Jennifer Williamson, Elizabeth Baumler Phd., Robert C. Addy Phd., Melissa F. Peskin Phd., Susan R. Tortolero, Christine M. Markham Phd.

Journal of Applied Research on Children: Informing Policy for Children at Risk

Background: Few HIV/STI and pregnancy prevention programs for youth in American Indian and Alaska Native (AI/AN) communities have been rigorously evaluated despite sexual health disparities in this population. This study reports the evaluation of a culturally adapted Internet-based HIV/STI and pregnancy prevention program for AI/AN youth, Native It’s Your Game (Native IYG).

Methods: A randomized study was conducted with 523 youth (12 to 14 years old), recruited from 25 tribal sites in Alaska, Arizona, and the Pacific Northwest. Participants were surveyed at baseline and upon completion of treatment or comparison interventions. Multivariable linear regression models were used to assess impact …

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 …

Evaluating The Therapeutic Efficacy Of Restoring Wild-Type P53 Activity In P53-Mutant Tumors, Connie A. Larsson

Dissertations and Theses (Open Access)

The p53 transcription factor is the most frequently altered in human cancers usually via missense mutations that undermine its transcriptional activity. Clinically, TP53 mutations have been shown to be remarkably predictive of refractoriness to treatment, resulting in poor outcome. Consequently, the development of p53 pathway activating agents is rapidly evolving and gaining more attention in cancer therapeutics research, with several small molecule compounds currently in preclinical and clinical trials. However, it remains largely unknown what types or proportions of p53-mutant tumors will respond to p53 restoration-based therapies.

Using a mouse model of Li Fraumeni syndrome, we genetically restored wild-type …

Mechanism Of Candida Albicans Biofilm And Virulence Inhibition By A Bacterial Secreted Factor, Carrie Graham

Dissertations and Theses (Open Access)

The human microbiome is a diverse polymicrobial population comprised of both fungi and bacteria. Perturbations of the normal microbiome can have a profound impact on health, including the development of infections. Exploitation of these polymicrobial interactions has the potential to provide novel treatment and prevention strategies for infectious diseases. Enterococcus faecalis, a Gram-positive bacterium, and Candida albicans, a polymorphic fungus, occupy overlapping niches as ubiquitous constituents of the gastrointestinal and oral microbiome. Both species are also amongst the most important and problematic, opportunistic nosocomial pathogens and are often co-isolated during infection. Surprisingly, these two species antagonize each other’s …

Serum Microrna-27b As A Screening Biomarker For Left Ventricular Hypertrophy, Yan Wang, Shuyan Chen, Yanhong Gao, Song Zhang

The Texas Heart Institute Journal

MicroRNA-27b (miR-27b) is frequently upregulated in pressure-overloaded hypertrophic hearts. The clinical implications of aberrant circulating miR-27b in the diagnosis and management of left ventricular hypertrophy warrant study. We investigated whether serum miR-27b is a biomarker for left ventricular hypertrophy (LVH).

We used stem-loop reverse-transcription quantitative polymerase chain reaction techniques to analyze serum miR-27b levels in 200 hypertensive patients with LVH, 100 hypertensive patients without LVH, and 100 healthy volunteers. We found that serum miR-27b levels were significantly higher in the hypertensive patients with LVH than in the hypertensive patients without LVH and in the healthy volunteers. Upon receiver operating characteristic …

Mitochondrial Fission After Traumatic Brain Injury, Tara Fischer

Dissertations and Theses (Open Access)

Mitochondrial dysfunction is a central feature in the pathophysiology of Traumatic Brain Injury (TBI). Loss of mitochondrial function disrupts normal cellular processes in the brain, as well as impedes the ability for repair and recovery, creating a vicious cycle that perpetuates damage after injury. To maintain metabolic homeostasis and cellular health, mitochondria constantly undergo regulated processes of fusion and fission and functionally adapt to changes in the cellular environment. An imbalance of these processes can disrupt the ability for mitochondria to functionally meet the metabolic needs of the cell, therefore resulting in mitochondrial damage and eventual cell death. Excessive fission, …

Computational Identification Of Noncoding Driver Mutations Based On Impact On Rna Processing, Kevin Zhu

Dissertations and Theses (Open Access)

Despite the prevalence of mutations in the noncoding regions of the DNA, their effects on cancer development remain largely uninvestigated. This is especially evident when compared to coding mutations, which have been relatively well-studied and, in certain cases, been identified as driver mutations for cancer. Recent studies, however, have identified noncoding mutations that frequently appear in certain types of cancer, which may be evidence that those mutations are important to cancer development. Nonetheless, the role of noncoding mutations in cancer remains unclear. A potential vector for understanding this mechanism is through observing the relation between noncoding mutations and functional RNA …

Integrative Cancer Immunogenomic Analysis Of Serial Melanoma Biopsies Reveals Correlates Of Response And Resistance To Sequential Ctla-4 And Pd-1 Blockade Treatment, Whijae Roh

Dissertations and Theses (Open Access)

Melanoma is the most malignant form of skin cancer. The five-year survival rate for metastatic melanoma is 19.9%. Although targeted therapy of BRAF and MEK inhibitors were developed for melanoma, resistance to therapy is inevitable. Immune checkpoint blockade, which reverses the suppression of the immune system, on the other hand, has shown a durable response in 20-30% of patients with metastatic melanoma. However, more predictive and robust biomarkers of response to this therapy are still needed, and resistance mechanisms remain incompletely understood. To address this, we examined a cohort of metastatic melanoma patients treated with sequential checkpoint blockade against cytotoxic …