Medicine and Health Sciences Commons^™

Building A Metabolic Bridge Between Glycolysis And Sphingolipid Biosynthesis : Implications In Cancer., Morgan L. Stathem

Electronic Theses and Dissertations

Cancer therapeutics has seen an emergence and re-emergence of two metabolic fields in recent years, namely bioactive sphingolipids and glycolytic metabolism. Anaerobic glycolysis and its role in cancer has been recognized in cancer biology over 90 years. In recent decades, the role of sphingolipids in cancer cell metabolism has gained recognition, notably ceramide’s essential role in programmed cell death and the role of the glucosylceramide synthase (GCS) in chemotherapeutic resistance. Despite this knowledge, a direct link between these two fields has yet to be concretely drawn. Herein, we show that in a model of highly glycolytic cells, generation of the …

Help-Seeking Behaviors Of South African Women After Sexual Offence Victimization : The Lived Experience., Sheila Young Steinbrenner

Electronic Theses and Dissertations

There is little known about South African women’s help-seeking behavior after sexual offence victimization. South Africa is estimated to have the highest rate of rape and sexual assault globally. However, only one in six women seek health services post victimization. The importance of medical and mental health care following victimization has been clearly established. Therefore understanding more about South African women’s help-seeking after victimization is profoundly important. The purpose of this study was to explore the lived experience of help-seeking behaviors of South African women after sexual offence victimization. Hermeneutic phenomenology as applied by van Manen provided the philosophical underpinnings, …

Inducible Tumor Difference Between Rapid And Slow Rat Nat2 Congenic Fischer 344 Rats Administered Methyl-Nitrosourea., Marcus W. Stepp

Electronic Theses and Dissertations

Human arylamine N-acetyltransferase 1 (NAT1) is a well-known phase II metabolic enzyme that has been associated with carcinogenesis. Its role in the biotransformation of aromatic and heterocyclic amine carcinogens has been investigated for many years, but more recent investigations focus on a possible endogenous role of human NAT1 in cancer initiation and progression. We conducted in vivo studies using homozygous Fischer 344 rats, congenic at the rat Nat2 locus for high (rapid) and low (slow) activity. Wistar Kyoto inbred rats were used to breed in the slow activity rat Nat2 locus into the Fischer 344 inbred rat, which contains the …

Effects Of Passive Immobilization On Locomotor Recovery After Spinal Cord Injury In Adult Rats., Kelsey Lee Stipp

Electronic Theses and Dissertations

Background: Spontaneous locomotor recovery in spinal rats has been attributed to animals moving freely in-cage. Environmental enrichment has been shown to increase in-cage movement and functional recovery subsequently. Anxiety has been shown to decrease overnight activity in rats. Methods: Rats were double-housed in medium cages (MC) or single-housed in tiny sized cages (TC). Slotted dividers allowed for partial isolation in TC. Overnight activity was monitored bi-weekly. The open field test and BBB’s were taken weekly. Gait analysis was performed at weeks six and eight. Results: MC showed higher overnight activity and improved gait overtime. No differences were found in BBB …

Bdnf Maintains Adult Taste Innervation And Is Required For Taste Nerve Regeneration After Injury., Lingbin Meng

Electronic Theses and Dissertations

Brain derived neurotropic factor (BDNF) is required for the gustatory neuron survival,target innervation, and taste bud maintenance during development. However, whether BDNF has any function in the adult gustatory system in normal conditions or after nerve injury is unclear. To address these issues, I inducibly removed BDNF in all cells expressing BDNF in adult mice. In the experimental animals, Bdnf expression decreased to 5% of control mice in the lingual epithelium and geniculate ganglion (p< 0.01) at both two weeks and ten weeks after tamoxifen administration. I found no effect on taste bud morphology at four weeks following Bdnf gene deletion. However, ten weeks following Bdnf gene deletion, P2X3-positive and TUJ1-positive gustatory innervation to individual taste buds was reduced by nearly half (each with p < 0.01) and both taste bud volume and taste cell number decreased 30% (each with p< 0.01). These experiments demonstrate that BDNF is required for maintenance of normal levels of taste innervation and normal taste bud morphology in adulthood. In addition, taste cells expressing PLCß2 (phospholipase C ß2), a marker for taste cells that respond to sweet, bitter and umami, did not decrease after Bdnf gene deletion in the adult. Thus, the missing taste cells are of another type. This indicates that taste cell loss is not uniform across the various taste cell types, even if nearly all taste cell types receive the P2X3 and TUJ1 innervation. Since BDNF is required for initial innervation of the taste system and supports taste bud innervation and size in adulthood, it could also be required for nerve reinnervation after injury. To determine if Bdnf is still expressed following nerve section, the chorda tympani nerve (taste nerve) was sectioned and Bdnf level was detected with Real Time RT-PCR. Bdnf continued to be expressed at normal levels from two days to two months post-surgery in both geniculate ganglion and tongue epithelium. Therefore, BDNF could be involved with chorda tympani regeneration. To determine if this was the case, the Bdnf gene was deleted in adult inducible transgenic mice (under the control of a Ubiquitin promoter) two weeks before chorda tympani nerve section. Taste bud number was reduced by half in all genotypes at two weeks post-surgery (p < 0.01). For the remaining taste buds, gustatory innervation was nearly gone with only a little innervation from the trigeminal nerve remaining in the taste bud (p < 0.01). Taste bud volume (p < 0.01) and taste cell number (p< 0.01) were reduced by half for both control and experimental genotypes. Eight weeks post-surgery, taste bud number recovered in mice without Bdnf gene deletion, but did not recover in mice following Bdnf gene deletion (p < 0.01). Gustatory nerve innervation returned in 70% of the taste buds in control mice (p< 0.01). For those reinnervated taste buds, both taste bud volume and taste cell number increased to normal levels. However, in mice lacking the Bdnf gene, gustatory fibers only reinnervated 7.8% of the taste buds (p < 0.01); for most uninnervated taste buds, both taste bud volume and taste cell number remained small. These experiments demonstrate that BDNF is crucial for promoting regeneration of gustatory nerve fibers in adulthood. Following gustatory nerve section, considerable adult plasticity has been observed on the contralateral side including enlarged taste buds with more cells (Guagliardo and Hill, 2007). To determine if this anatomical change was associated with alter Bdnf expression. I examined Bdnf level in the geniculate ganglion and tongue epithelium on the contralateral side following chorda tympani nerve section. Results showed Bdnf expression increased two fold at two weeks post-surgery in geniculate ganglion on the contralateral side (p < 0.05), indicating BDNF may involve with the observed plastic changes. To determine if the increase in taste bud size was associated with increased innervation and/or regulated by BDNF, the Bdnf gene was then deleted in inducible knockout mice before nerve surgery, and taste bud size and amount of innervation were measured on the contralateral side. The results showed taste bud volume, taste cell number and a marker for nerve fibers all increased on the contralateral side in mice without Bdnf gene deletion at eight weeks post-surgery. This indicates that larger taste buds could be supported by increased TUJ1 positive fibers from trigeminal nerve. In addition, in mice lacking Bdnf, taste bud volume, taste cell number and innervation did not increase on the contralateral side after surgery, which indicates that Bdnf may contribute to larger taste buds on the contralateral side following nerve section by supporting increased innervation to the larger taste buds.

The Impact Of Preconception Maternal Stress On Fecundability And Adverse Pregnancy Outcomes., Shekufe Akhter

Electronic Theses and Dissertations

It has been commonly hypothesized (and widely believed) that maternal stress either prior to or during pregnancy can adversely affect fertility and pregnancy outcomes. However, surprisingly few epidemiologic studies have rigorously tested these hypotheses. The current study evaluated the effects of pre-conception self-reported stress on fecundability and spontaneous abortion. The study population was derived from the Mount Sinai Study of Woman Office Workers with 487 women included. Women recorded stress (scale from 1 to 4) and covariate information in a daily diary for 12 cycles or until pregnant. Results indicated a significantly increased risk of spontaneous abortion for women with …

Predictors Of Uncertainty, Stress, Anxiety, And Depressive Symptoms Of Parents Of Preterm Infants In The Neonatal Intensive Care Unit., Maryam Isa Alaradi

Electronic Theses and Dissertations

Admission of a sick neonate to the neonatal intensive care unit (NICU) can be a very stressful experience for the parents. Parents strive to deal with stress, uncertainty, anxiety, and depressive symptoms in this potentially threatening environment. Research on parental uncertainty in the neonatal population is limited. Moreover, very few studies examined predictors of stress, anxiety and depressive symptoms in parents of NICU infants. The purpose of this study was to identify predictors of uncertainty, stress, anxiety, and depressive symptoms in parents of preterm infants in the NICU. A cross-sectional explorative design was used to recruit a convenience sample of …

Evaluation Of The Safety And Pharmacokinetic Profile Of The Broad Spectrum Antiviral Lectin Griffithsin., Christopher Lynn Barton

Electronic Theses and Dissertations

Carbohydrate binding agents that target viral envelope glycans are being studied for their potential use as microbicides and antiviral therapeutics. Griffithsin is a lectin originally identified in a red alga Griffithisia sp. Multiple studies have shown that GRFT inhibits HIV-1, Coronaviruses, Hepatitis C, influenza and Ebola virus replication in vitro. This antiviral activity suggests potential uses in chemoprophylaxis and disease treatment. However, safety of GRFT administration has not been extensively studied. In vivo testing--chronic subcutaneous treatment as well as single dose subcutaneous, oral, and intravenous administrations of Griffithsin in Sprague Dawley Rats (Rattus Norvegicus)--was used to assess Griffithsin’s pharmacokinetic properties …

Cholinergic Inhibition Of Lipopolysaccharide Induced Matrix Metalloproteinase In Immune Cells., Harrison Black,

Electronic Theses and Dissertations

Background: Matrix metalloproteinase (MMPs) are proteins that have a unique role in immunity, tissue remodeling, and tumorigenesis. MMPs can break down extracellular components, release bioactive molecules, and act on pro-inflammatory cytokines, chemokines and other proteins to regulate varied aspects of inflammation and immunity. Nicotine (3-(1-methyl-2-pyrrolidinyl) pyridine), a key toxic component of tobacco, is thought to dysregulate matrix metalloproteinase secretion in immune cells. Aim: Examine the effect of nicotine on MMP9 secretion and activity in primary monocytes. Methods: Primary monocytes were stimulated with LPS (1 µg/ml) and Nicotine (100 ng/ml) and MMP9 secretion were studied. Gel zymography and ELISA techniques were …

Bone Strength And Architecture : Pharmacological Targeting Of Camkk2 As A Method For Enhancing Bone Quality., Zachary James Pritchard

Electronic Theses and Dissertations

Mice lacking or pharmacologically inhibited for calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) have enhanced bone mass and microarchitecture. This enhanced bone mass and architecture is due to changes in osteoblast and osteoclast numbers as well as activity. Whether the enhanced bone mass translated to increased bone quality and strength was further explored by developing a method to directly test the trabecular strength of the distal femur. Micro computed tomography (CT)-based measurement of the length of the epiphysis of the distal femur, aided in its removal, allowing the exposure of the trabecular bone volume used to determine the microarchitecture parameters. Following …

Bilateral Maxillary Canine-First Premolar Transposition In Permanent Dentition, Sarwat Memon, Mubassar Fida

Department of Surgery Docs

ABSTRACT Transposition is a dental anomaly characterized by the exchange of position between two adjacent teeth, especially in relation to their roots, or development and eruption of a tooth in a position normally occupied by a nonadjacent tooth. Transposition of the maxillary canine and first premolar has a low prevalence in the population and it primarily affects maxillary canines and premolars. The aetiology of the transposition remains unclear, although it has been associated with genetic factors. It may also be related to a combination of localised factors such as malformation of adjacent teeth, tooth agenesis, retention of the deciduous canine …

Persistent Hepatic Structural Alterations Following Nanoceria Vascular Infusion In The Rat, Michael T. Tseng, Qiang Fu, Khoua Lor, G. Rafael Fernandez-Botran, Zhong-Bin Deng, Uschi M. Graham, D. Allan Butterfield, Eric A. Grulke, Robert A. Yokel

Chemistry Faculty Publications

Understanding the long-term effects and possible toxicity of nanoceria, a widely utilized commercial metal oxide, is of particular importance as it is poised for development as a therapeutic agent based on its autocatalytic redox behavior. We show here evidence of acute and subacute adverse hepatic responses, after a single infusion of an aqueous dispersion of 85 mg/kg, 30 nm nanoceria into Sprague Dawley rats. Light and electron microscopic evidence of avid uptake of nanoceria by Kupffer cells was detected as early as 1 hr after infusion. Biopersistent nanoceria stimulated cluster of differentiation 3⁺ lymphocyte proliferation that intermingled with nanoceria-containing …

Anxiety, Depression And Smoking Status Among Adults Of Mexican Heritage On The Texas-Mexico Border, Anna V. Wilkinson, Kristina Vatcheva, Adriana Pérez, Belinda M. Reininger, Joseph B. Mccormick, Susan P. Fisher-Hoch

School of Mathematical & Statistical Sciences Faculty Publications

The goal of the current analysis is to examine relationships between smoking status and anxiety and depression among adults of Mexican heritage to inform the development of culturally relevant smoking cessations efforts. Mexican heritage residents (N=1,791) of the city of Brownsville, TX, aged 18 years or older, enrolled in the Cameron County Hispanic Cohort, were selected through two stage cluster sampling of randomly selected census tracts from the first and third quartile of SES using Census 2000. Among current smokers, anxiety and depression scores were highest among women who had not completed high school (p<0.05). Former smoking women, but not men, with at least a high school education and former smoking women born in the United States reported higher levels of anxiety and depression than never smoking women. Negative affective states may represent a greater barrier to smoking cessation among women than men.

The Kras/Mapk Pathway And Ligand Independent Activation Of Erα: Implications For The Treatment Of Endometrial Cancer, Kari Ring

Dissertations and Theses (Open Access)

Hormonal therapy remains a first line option for the treatment of recurrent endometrial cancer (EC), however, many tumors demonstrate de novo or acquired resistance. Member kinases of the PI3K/AKT and Ras/MAPK pathways activate estrogen receptor α (ERα) independent of estrogen, however, few studies have evaluated the role of the Ras/MAPK pathway in predicting response to hormonal therapy in EC. The aims of this project were to evaluate the role of ligand independent activation of ERα in EC and to explore therapeutic implications for the treatment of recurrent EC.

A xenograft model for recurrent EC was used to evaluate the effect …

Role Of Macrophages In Adaptive Resistance To Anti-Vegf Therapy, Heather Dalton

Dissertations and Theses (Open Access)

Background: The clinical implementation of therapies targeting the VEGF pathway in cancer has been limited by acquired resistance; yet, the mechanisms by which this occurs is unclear. We investigated the role of macrophages in the development of acquired resistance to anti-VEGF antibody (AVA) therapy.

Materials and Methods: We first established a murine ovarian cancer model of resistance to anti-VEGF therapy. Using this model we investigated changes in macrophage infiltration during AVA sensitive and resistant phases. We also investigated the in vivo effects of macrophage depletion at the emergence of anti-VEGF resistance and in upfront combination with AVA therapy. In vitro …

Volumetric Scintillation Dosimetry For Scanned Proton Beams, Daniel G. Robertson

Dissertations and Theses (Open Access)

Scanned beam proton therapy is a promising cancer treatment modality which is becoming more widely available with the increasing number of proton radiotherapy centers. Scanned proton beams can produce complex 3D dose distributions, presenting a challenge for adequate quality assurance testing. Because each scanned beam dose measurement requires the delivery of the entire field, multiple measurements can be time consuming. These quality assurance challenges limit the number of patients who can be treated with this modality. The overall objective of this project is to increase the safety and availability of complex proton therapy treatments by developing a fast volumetric scintillation …

Novel Serum Biomarkers For Lung Cancer Early Diagnosis And Clinical Outcome, Fanmao Zhang

Dissertations and Theses (Open Access)

The five-year survival rate for all stages of lung cancer combined is only 17%, which has changed little over the past 40 years. Despite the tremendous efforts made, serum biomarkers with clinical utility for lung cancer early detection and clinical outcome prediction are still lacking. Metabolic alterations have been recognized as an emerging hallmark of cancer. We aimed to investigate the metabolic changes associated with lung cancer and to identify novel clinically applicable serum biomarkers for lung cancer early diagnosis and clinical outcome.

Serum metabolites are potential biomarkers for lung cancer early detection. We first performed global metabolomic profiling followed …

Multiple Myeloma And Its Treatment Alter Peripheral Nervous System Structure And Function, Alyssa K. Kosturakis

Dissertations and Theses (Open Access)

MULTIPLE MYELOMA AND ITS TREATMENT ALTER PERIPHERAL NERVOUS SYSTEM STRUCTURE AND FUNCTION

Alyssa Katarina Kosturakis, BA

Supervisory Professor: Patrick M. Dougherty, PhD

Peripheral neuropathy is among the most deleterious side effects of frontline chemotherapeutics used to treat prevalent cancers. Chemotherapy-induced peripheral neuropathy (CIPN) refers to the collection of symptoms (e.g. pain, paresthesias and dysesthesias) that develop in distal, glabrous (non-hairy) skin of 20 to 100% of patients treated with chemotherapy. Peripheral neuropathy negatively impacts quality of life in cancer patients and survivors, is refractory to treatment, and is the impetus for dose-reduction and/or cessation of chemotherapy, thereby limiting treatment. Proteasome …

Notch Signaling Inhibited By Ikaros1 In Human T-Cell Acute Lymphoblastic Leukemia, Camille W. Graham

Dissertations and Theses (Open Access)

The highly conserved Notch signaling pathway regulates cell growth, differentiation, survival and apoptosis. In hematopoiesis, Notch signaling drives commitment to the T-cell fate and promotes differentiation, T-cell receptor signaling and immune function. In T-cells, Notch signaling is oncogenic when constitutively active, promoting proliferation and survival while inhibiting differentiation. The majority of patients with T-cell acute lymphoblastic leukemia (TALL) have activating Notch mutations. Similarly, Notch activation is present in more than 75% of murine T-ALL models. In murine T-ALL, loss of Ikaros, a zinc finger transcriptional regulator, leads to disrupted differentiation and also cooperates with activated Notch signaling to promote T-ALL. …

Regulators Of Bacterial Cell Division: Investigations Of Min Oscillation And Ftsa Activity, Jennifer R. Herricks

Dissertations and Theses (Open Access)

Cytokinesis is a fundamental process that is essential for bacterial proliferation. The cytokinetic machinery in bacteria is termed the “divisome”. The divisome is a complex of proteins that forms a ring at midcell over dividing nucleoids. In order for daughter cells to form, the divisome must constrict. As constriction occurs, two new cell poles are formed, one for each daughter cell. The first step in divisome formation is the assembly of FtsZ into a Z ring. The work presented in this dissertation focuses on two proteins that regulate the Z ring: MinD, which is a part of the Min system …

Potential Roles Of Peroxidases In Caenorhabditis Elegans Innate Immunity, George R. Tiller, George R. Tiller

Dissertations and Theses (Open Access)

The production of ROS (reactive oxygen species) in response to pathogen detection is a rapid, nonspecific response that is evolutionarily conserved from nematodes to humans. ROS serve as direct and indirect effectors of innate and adaptive immunity. In Caenorhabditis elegans, a ROS burst is observed during infection and is mediated by the dual oxidase BLI-3, which produces H₂O₂. RNAi (RNA interference) to reduce the amount of BLI-3 results in a significant increase in susceptibility to pathogens, suggesting BLI-3 has a role in the immune response. However, H₂O₂ by itself is not a …

Genetic Predictors Of Metabolic Side Effects Of Diuretic Therapy, Jorge L. Del Aguila

Dissertations and Theses (Open Access)

Thiazide diuretics are a recommended first-line monotherapy for hypertension (i.e.SBP>140 mmHg or DBP>90 mmHg). Even so, diuretics are associated with adverse metabolic side effects, such as hyperlipidemia, hyperglycemia and hypokalemia which increase the risk of developing type II diabetes. This thesis used three analytical strategies to identify and quantify genetic factors that contribute to the development of adverse metabolic effects due to thiazide diuretic treatment. I performed a genome-wide association study (GWAS) and meta-analysis of the change in fasting plasma glucose and triglycerides in response to HCTZ from two different clinical trials: the Pharmacogenomic Evaluation of Antihypertensive Responses …

Targeting The Redox System To Overcome Mechanisms Of Drug Resistance In Chronic Lymphocytic Leukemia, Marcia A. Ogasawara

Dissertations and Theses (Open Access)

Chronic Lymphocytic Leukemia (CLL) is the most common form of leukemia diagnosed in Western countries and is characterized by clonal expansion of B cells. The clinical course of CLL is diverse and nearly 50% of patients present with chromosomal abnormalities. Deletion of the short arm on chromosome 17 (del17p) occurs in 5-7% of cases and presents with the shortest median survival time and often respond poorly to therapy. The tumor suppressor gene, TP53 is located on this region and it is well established that the p53 protein regulates multiple functions including: mitochondria biogenesis, response to DNA damage and redox balance. …

Development Of A New Independent Monte Carlo Dose Calculation Quality Assurance Audit To Ol For Clinical Trials, Austin M. Faught

Dissertations and Theses (Open Access)

Introduction: Commercially available treatment planning systems (TPS) may use a number of different radiation dose calculation algorithms during the planning process. The Radiological Physics Center (RPC), tasked with ensuring clinically comparable and consistent dose delivery amongst institutions participating in NCI funded multi-institutional clinical trials, has traditionally relied upon measurements to achieve this objective. As a supplement to the tools used by the RPC, an independent dose calculation tool is needed to determine patient dose distributions in three dimensions so as to act as a quality assurance tool for the dose calculations.

Methods: Multiple source models representing the output of Elekta …

The Role Of The C5a Receptor In Host Defense Against Listeria Monocytogenes, Daniel Calame

Dissertations and Theses (Open Access)

Listeria monocytogenes (Lm) is a major cause of mortality resulting from food poisoning in the United States. While the complement component C5 is known to be protective in listeriosis, it is unknown how its cleavage fragment C5a participates. Here we show in a model of systemic Lm infection that the C5a receptor is essential for host defense. C5aR-/- mice have reduced survival and increased bacterial burden in the liver and spleen in comparison to WT mice. Surprisingly, C5aR-/- mice also have a dramatic reduction in splenocyte numbers resulting from elevated cell death as indicated by TUNEL staining and caspase 3 …

The Oncogenic Map Kinase Signaling Pathway Modulates Mhc-I Surface Expression In Melanoma, Sherille Denae Bradley

Dissertations and Theses (Open Access)

The mitogen-activated protein kinase (MAPK) pathway is a cascade of serine-threonine kinases involved in cell growth, proliferation, and apoptosis; it is one of the most well-known pathways associated with melanoma progression. The MAPK pathway is constitutively activated in melanomas due to mutations in the signaling components, particularly the proto-oncogene BRAF ^V600E that accounts for (40-50%) of these cases. Metastatic melanoma is one of the deadliest and most aggressive forms of cancer, with a 3-year survival rate of less than 15%. Immunotherapies that utilize cytotoxic T lymphocytes (CTLs) have proven to be very effective at inducing regressions of large, bulky tumors, …

Roles For B-Raf Kinase In The Specific Regulation Of Α4Β1 Integrin In T Cells, Wells S. Brown

Dissertations and Theses (Open Access)

The regulation of integrin-mediated adhesion is of vital importance to adaptive and innate immunity. Integrins are versatile proteins and mediate T cell migration and trafficking by binding to ECM or other cells, as well as initiating intracellular signaling cascades promoting survival or activation. The mitogen activated-protein kinase (MAPK) pathway is known to be downstream from integrins and regulate survival, differentiation, and motility. However, secondary roles for canonical MAPK pathway members are being discovered. We show chemical inhibition of RAF by Sorafenib or shRNA-mediated knockdown of B-Raf reduces T cell resistance to shear stress to α4β1 integrin ligands vascular cell adhesion …

The Role Of Traf6 Phosphorylation In Src/Traf6-Mediated Ikk, Jnk, Akt Activation And Tumorigenesis, Yun Seong Jeong

Dissertations and Theses (Open Access)

TRAF6 E3 ligase regulates numerous essential biological processes such as innate immune response, cell survival and osteoclast differentiation. Upon activation, it mediates activation of IKK/NF-κB and JNK signaling in response to engagement of toll-like receptor 4 (TLR4), interleukin-1 receptor (IL-1R), and receptor activator of NF-κB (RANK) to their cognate ligands, including lipopolysaccharide (LPS), IL-1, and RANK ligand (RANKL). Recently, TRAF6 has also been shown to be involved in Akt signaling activation upon activation of insulin-like growth factor-1 receptor (IGF-1R), in turn orchestrating cell survival and tumorigenesis. Therefore, TRAF6 is a key player for the activation of IKK, JNK and Akt …

Pancreatic Ribonuclease Functions As An Epidermal Growth Factor Receptor Ligand Independently Of Its Enzyme Activity And Contributes To Cetuximab Resistance, Heng-Huan Lee

Dissertations and Theses (Open Access)

Ribonuclease (RNase) with its catalytic enzyme activity to degrade RNAs has been shown as a diagnostic serum marker for pancreatic cancer and has also been suspected to have an unidentified cell surface receptor. Epidermal growth factor receptor (EGFR), a well-characterized receptor tyrosine kinase is an effective therapeutic target in multiple cancer types. However, clinical trials targeting EGFR have not demonstrated improved therapeutic efficacy in pancreatic cancer. Here, we show that both bovine pancreatic RNase A (bRNaseA) and human RNase 5 (hRNase5) act as EGFR ligands and directly activate EGFR to promote epithelial-mesenchymal transition. This ligand-like activity is independent of RNases’ …

Targeting The Mdm2-P53 Axis For The Treatment Of Dedifferentiated Liposarcoma, Katelynn Bill

Dissertations and Theses (Open Access)

Dedifferentiated liposarcoma (DDLPS) is an aggressive malignancy characterized by a high rate of recurrence and dismal patient outcome. Minimal improvement in patient survival has been made in the last several decades, highlighting the crucial need for improved therapeutic strategies. A better understanding of the molecular deregulations underlying DDLPS would facilitate the discovery of improved therapeutic approaches. MDM2 is a well characterized oncoprotein and the most known negative regulator of p53. MDM2 amplification is considered the “hallmark” of DDLPS. Additionally, these tumors are known to harbor wild-type p53. We sought to take advantage of this knowledge and evaluate the role of …