Life Sciences Commons^™

Molecular Investigation Into The Biologic And Prognostic Elements Of Peripheral T-Cell Lymphoma With Regulators Of Tumor Microenvironment Signaling Explored In Model Systems, Tyler Herek

Theses & Dissertations

Peripheral T-cell lymphoma (PTCL) is heterogenous group of mature T-cell neoplasms characterized by distinctive transcriptional and genetic lesions. Herein, we investigated DNMT3A mutations in angioimmunoblastic T-cell lymphoma (AITL, n = 176) and novel molecular subtypes (i.e., PTCL-GATA3, n = 61 and PTCL-TBX21, n = 80) within PTCL- NOS and observed significant biological and prognostic differences associated with DNMT3A mutations. DNMT3A-mutated PTCL-TBX21 cases showed inferior overall survival (OS; p < 0.005), with DNMT3A mutations (DNMT3A-MT) skewed toward the methyltransferase domain and in the dimerization domain (S881-R887). Transcriptional profiling demonstrated significant enrichment of activated CD8⁺ T-cell cytotoxic gene signatures in the tumor microenvironment of DNMT3A-MT PTCL-TBX21 cases. Genome-wide methylation analysis of DNMT3A-R882/Q886 versus wild-type in PTCL-TBX21 cases demonstrated hypomethylation in target genes regulating T-cytotoxic genes, TCR …

Functional Characterization Of Cancer-Associated Dna Polymerase Ε Variants, Stephanie R. Barbari

Theses & Dissertations

Replicative DNA polymerases ε (Polε) and δ (Polδ) achieve high fidelity DNA synthesis through a precise balance of polymerization and exonucleolytic proofreading. Errors that escape proofreading are corrected by DNA mismatch repair (MMR). Ultramutated human cancers with proficient MMR carry alterations in the exonuclease domain of Polε, which were initially predicted to abolish proofreading. However, functional studies in yeast of the most recurrent Polε-P286R variant suggested defects beyond a loss of exonuclease activity. Indeed, biochemical analysis of the yeast Polε-P286R analog revealed increased polymerization capacity in addition to decreased proofreading, which enables efficient mismatch extension and bypass of replication-blocking non-B …

Nuclear Receptor Coactivator 3 In Endoplasmic Reticulum Stress And Stress Granule Dynamics In Pancreatic Cancer, Andrew Kisling

Theses & Dissertations

Pancreatic cancer is predicted to be the second-leading cause of cancer-related deaths within the next decade. Nuclear receptor coactivator 3 (NCOA3/SRC3/AIB1) regulates an array of metabolic and signaling pathways and has been established by our group and others as a critical regulator pancreatic cancer progression and metastasis. A recent study demonstrated NCOA3 regulation by the IRE1α-XBP1 axis of the unfolded protein response (UPR), suggesting a link between NCOA3 and cellular stress management. Furthermore, NCOA3 has been shown to directly bind to a scaffolding protein of stress granules (SGs). Since SG assembly is regulated by the UPR, we hypothesized that NCOA3 …

A Pkcα-Mediated Growth Suppressive Mek-Erk Signaling Axis In Intestinal Epithelial Cells, Navneet Kaur

Theses & Dissertations

Members of the protein kinase C (PKC) family of serine/threonine kinases are involved in regulation of fundamental cellular functions, including proliferation, differentiation, survival, migration, and transformation. Increasing evidence points to anti-proliferative and tumor suppressive role of PKCs. Our laboratory and others have reported that the classical PKC isozyme, PKCαnegatively regulates proliferation and tumorigenesis in the intestinal epithelium. Our laboratory has further determined that PKCα signaling induces a program of cell cycle withdrawal in intestinal epithelial cells that involves downregulation of the pro-proliferative proteins, cyclin D1 and Id1, and upregulation of the cyclin dependent kinase (CDK) inhibitor, p21^Cip1. Unexpectedly, …

Development Of A Muc16-Targeted Near-Infrared Antibody Probe For Fluorescence-Guided Surgery Of Pancreatic Cancer, Madeline T. Olson

Theses & Dissertations

Pancreatic cancer (PDAC) is an extremely lethal disease with an overall survival rate of 10%. Surgery remains the only potentially curative treatment option, but resections are complicated by infiltrative disease, proximity of critical vasculature, peritumoral inflammation, and dense stroma. Surgeons are limited to tactile and visual cues to differentiate cancerous tissue from normal tissue. Furthermore, translating preoperative images to the intraoperative setting poses additional challenges for tumor detection, and can result in undetected and unresected lesions. Thus, PDAC has high rates of incomplete resections, and subsequently, disease recurrence. Fluorescence-guided surgery (FGS) has emerged as a method to improve intraoperative detection …

Molecular Mechanisms Of Aberrant Protein Glycosylation In Pancreatic Cancer Stemness And Metastasis, Frank Leon

Theses & Dissertations

A myriad of genetic and other abnormal changes underlies the aggressiveness and dissemination properties observed in pancreatic cancer (PC). Aberrant protein glycosylation is a commonly observed feature in PC. The modification of protein O-glycosylation is mediated by glycosyltransferases, which attach and sequentially elongate monosaccharides on Serine/Threonine (Ser/Thr) motifs. Aberrant glycosylation is recognized as an emerging hallmark of cancer where a disruption in normal glycosylation results in irregular O-glycans.

This dissertation research has investigated the consequences of aberrant protein glycosylation on stemness and enhancement of metastatic properties in pancreatic ductal adenocarcinoma (PDAC). Several publications have reported aberrant O-glycosylation increases in oncogenic …

Deep Multi-Omics Investigations Elucidate Novel Oncogenesis Paradigms, Therapeutic Targets, And Mechanisms Of Treatment Resistance In Cancer, Daniel Cui Zhou

Arts & Sciences Electronic Theses and Dissertations

No abstract provided.

Understanding The Kinomic Contributions To Tyrosine Kinase Inhibitor Resistance In Triple Negative Breast Cancer, Cory Lefebvre

Electronic Thesis and Dissertation Repository

Resistance to tyrosine kinase inhibitors (TKIs) presents a growing challenge in the development of therapeutic targets for cancers such as triple negative breast cancer (TNBC), where conventional therapies are ineffective at combatting systemic disease. Potential targets in TNBC include the receptor tyrosine kinases EGFR (epidermal growth factor receptor) and c-Met, however, targeted anti-EGFR and anti-c-Met therapies have faced challenges in clinical trials due to acquired resistance. We hypothesize that response versus resistance of triple negative breast cancer to the tyrosine kinase inhibitors erlotinib and cabozantinib is mediated by compensatory changes in the kinome and phosphoproteome. To test this, we (1) …

Kindlin-1 Is Involved In Spreading, Migration, And Protein Regulation In Epidermal Scc-13 Cells, Naomi Mishan

Electronic Thesis and Dissertation Repository

Kindlin-1 is a scaffold protein linking the cytoskeleton to the extracellular matrix. Loss of function mutations in the FERMT1 gene (encoding Kindlin-1) cause gastrointestinal and skin defects associated with increased susceptibility to aggressive epidermal squamous cell carcinoma (SCC). This study investigated the consequences of targeted FERMT1 inactivation in the SCC-13 cell line of epidermal SCC. My studies demonstrate Kindlin-1 is not essential for SCC-13 proliferation or clonogenic potential in culture. Kindlin-1 was required for cell spreading on collagen I, but not on laminin-332, and its absence enhanced SCC-13 directional migration. Finally, I identified several proteins involved in tumor formation and …

Atrx Inactivation And Idh1-R132h Drive Preferential Sensitivity To Proton Vs. X-Ray Radiotherapy In Glioma Stem Cells, Ángel Adrián Garcés

Dissertations & Theses (Open Access)

Background: Glioma Stem Cells (GSCs) are self-renewable, treatment resistant cells in the glioma tumor mass known to promote tumor development. In contrast to traditional photon-based radiation therapy (XRT), proton radiation therapy (PRT) may induce more complex DNA damage and therefore might have the potential to eliminate GSCs. Although previous studies have individually linked IDH mutations, specifically IDH1^R132H, and ATRX inactivating mutations to improved patient outcomes and suppressed DNA damage repair compared to their respective wild-types, the mechanisms by which these two genetic alterations interact in GSCs treated with PRT compared to XRT are currently unknown. We hypothesize that …

4d Ex Vivo Crispr/Cas9 Whole-Genome Screen To Identify Genes Regulating Lung Cancer Metastasis, Alexandria Plumer

Dissertations & Theses (Open Access)

Metastatic lung cancer has a 5-year survival rate of 5%. Lung cancers tend to be asymptomatic until late stages, and almost 90% are not diagnosed until they are advanced. Metastases are very rare events, often initiated by a single cell from a primary tumor into a new niche at a distant location. Investigation of the early metastatic process is of urgent need for the development of early diagnostics and targeted therapeutics. We performed a proof-of-concept CRISPR/Cas9 whole genome knockout screen in the A549 lung adenocarcinoma cell line and utilized a novel ex vivo 4D lung metastasis model to find gene …

Longitudinal Monitoring Of Tumor Response To Immune Checkpoint Inhibitors Using Diffuse Optical Spectroscopy, Joel Isaac Rodriguez Troncoso

Graduate Theses and Dissertations

Immune checkpoint drugs have completely changed the way people treat metastatic melanoma and non-small-cell lung cancer. While the impacts of these immunological checkpoints and their suppression on T cell function are well characterized, their consequences on the tumor microenvironment are not. In a CT26 mouse colorectal cancer model, we employed diffuse reflectance spectroscopy to track in vivo tumor microenvironmental alterations in response to immune checkpoint inhibitors. On three separate days, animals bearing CT26 tumor xenografts were given anti-PD-L1, anti-CTLA-4, a combination of both inhibitors, and isotype control. Within the first 6 days, monotherapy with either anti-PD-L1 or anti-CTLA-4 resulted in …

Differentiating The Mechanistic Role And Chemotherapeutic Potential Of Src And Podoplanin In Oncogenic Transformation, Edward P. Retzbach

Graduate School of Biomedical Sciences Theses and Dissertations

There were an estimated 20 million new cancer cases worldwide in 2020, resulting in nearly 1000 deaths per hour [1]. Oral cancer exemplifies the difficulties of treating cancer patients. The first line for oral cancer treatment is surgery and radiation that can lead to patient disfigurement and decreased quality of life in cancer survivors [2-4]. Though there have been many developments in chemotherapy in the last 30 years, the 50% mortality rate associated with oral cancer has not changed [4, 5]. Longitudinal studies that track survival rates in oral cancer patients demonstrate a 3-fold reduction in patient deaths when patients …

Lgr5 Regulation Of Stat3 Signaling And Drug Resistance In Colorectal Cancer, Tressie Posey, Tressie Alexandra Posey

Dissertations & Theses (Open Access)

LGR5 Regulation of STAT3 Signaling and Drug Resistance in Colorectal Cancer

Tressie Alexandra Capri Posey B.S.

Advisory Professor: Kendra Carmon, Ph.D.

The greatest difficulty in treating colorectal cancer (CRC) is the development of drug resistance which leads to relapse after treatment and progression to metastasis. Cancer stem cells (CSCs) are believed to drive relapse because of their capacity to self-renew, acquire resistance mechanisms, and differentiate promoting tumor growth and heterogeneity. Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5), is a bona-fide marker of CSCs and has been considered a viable target for CSC specific therapeutic development. While we showed targeting LGR5 …

Stat3 Inhibits Type I Interferon Signaling In Type I Conventional Dendritic Cells, Taylor Chrisikos

Dissertations & Theses (Open Access)

Conventional dendritic cells (cDCs) are an essential immune population, responsible for controlling adaptive immunity and tolerance. Recently, type I cDCs (cDC1s) have been delineated as a distinct cDC subset, uniquely responsible for coordinating T cell-mediated immunity against pathogens and tumors. Although the importance of cDC1s is now well established, the mechanisms that regulate cDC1 function remain largely unknown. Signal Transducer and Activator of Transcription 3 (STAT3) mediates the intracellular signaling of interleukin 10 (IL-10), an immunosuppressive cytokine. Therefore, we hypothesized that STAT3 and IL-10 inhibit cDC1 function and induction of T cell-mediated immunity. Herein, we show that IL-10 inhibits polyinosinic:polycytidylic …

Investigating Therapeutic Strategies To Target Metabolic Vulnerabilities Of Nsclc Tumors With Mutant Keap1 Gene, Pranavi Koppula

Dissertations & Theses (Open Access)

The metabolic vulnerability of cancers has long been envisaged as an attractive window to develop novel therapeutic strategies. Metabolic flexibility at the cellular level encompasses the efficient rerouting of anabolic and catabolic pathways in response to varying environmental stimuli to maintain cellular homeostasis and sustain proliferation. The primary objective of this study is to identify metabolic vulnerabilities bestowed by KEAP1/NRF2 signaling axis through SLC7A11. SLC7A11 is a transcriptional target of NRF2, an essential regulator of cellular anti-oxidant response. Under unstressed basal conditions, NRF2 interacts with KEAP1, a tumor suppressor gene and a substrate adaptor protein of the Cullin3-dependent ubiquitin ligase …

Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers by organ site with a 5-year survival rate of just 10.8%. This is largely because most patients do not experience symptoms until the disease has already metastasized. The best hope to cure PDAC is surgery, which can only be done with a curative intent at an early stage when the disease is localized. There are no reliable circulating, body-fluid-based biomarkers to detect early stage PDAC or its precursor lesions in a timely manner for effective surgical intervention. When potential PDAC precursor lesions, such as mucinous pancreatic cysts are found, there are …

Role Of Sex Differences On Cancer Cachexia Progression And Fibrosis During Cancer Cachexia Development, Wesley Haynie

Graduate Theses and Dissertations

Cancer cachexia is a multifactorial wasting syndrome characterized by losses in bodymass >5% and occurs in approximately 80% of all cancer patients. Chronic inflammation and fibrosis play roles in cancer cachexia and a greater understanding of these contributing pathways to this pathology will pave the way for potential therapeutic avenues. While inflammation and fibrosis have been researched in various models of cancer cachexia, little to no studies have been performed in both sexes as most previous studies focus on males. PURPOSE The purpose of these studies is to investigate the role of fibrosis on cancer cachexia development as well as …

Insights Into O-Glcnac-Mediated Regulation Of Galectin Expression And Secretion In Promyelocytic Hl-60 Cells, Adam J. Mctague

Electronic Thesis and Dissertation Repository

Galectins are a family of -galactoside-binding proteins involved in cell stress responses and differentiation. Galectins are multifunctional proteins widely studied in many cell models including acute myeloid leukemia HL-60 cells where they mediate numerous intra- and extracellular functions in response to many stress-inducing stimuli. O-GlcNAcylation is a dynamic post-translational modification implicated in the regulation of many cellular diseases including cancers. The O-GlcNAc mediated expression and secretion of galectins during neutrophilic differentiation was examined in HL-60 cells. Galectin gene (LGALS), galectin protein expression, and galectin secretion were determined by RT-qPCR, immunoblotting, and ELISA, respectively. Inhibition of O-GlcNAcylation induced markers of differentiation …

Molecular Mechanism Of Action Of The Natural Polyphenolic Compound And The P300 Inhibitor “Carnosol” Against The Triple Negative Breast Cance, Halima Ali Mohammed Salem Alsamri

Dissertations

Carnosol, a naturally occurring Phyto polyphenol found in sage, oregano, and rosemary, has been extensively studied by our laboratory for its anticancer effects in various types of cancer. In human Triple-Negative Breast Cancer (TNBC), carnosol was shown to inhibit cellular viability, colony growth, induced cell cycle arrest, autophagy, and apoptosis. Nonetheless, very little is known about the molecular mechanism of action. In the current study, the ability of carnosol to inhibit metastasis and tumour growth was examined. Wound healing and invasion assays revealed that carnosol inhibited migration and invasion at non-cytotoxic concentrations of MDA-MB-231 cells. Also, carnosol was found to …

Synthesis, Characterization And Applications Of Peptide-Coated Nanoparticles, Mina Sadat Poursharifi

Dissertations, Theses, and Capstone Projects

Ovarian Cancer (OC) is the most lethal female malignancy worldwide, mainly due to its high recurrence rate and poor diagnosis. Most patients present with late stage of the disease, and less than 25% of patients survive the five years mark. Nanotherapy provides significant and unique benefits for drug efficacy, as nanoparticles (NPs) can increase the solubility, bioavailability, and permeability of many potent drugs. Poly(lactic-co-glycolic acid) (PLGA) is one of the most successful biodegradable polymers used in NPs formulations, mainly due to its biocompatibility and biodegradability. Polyethylene glycol (PEG) is one of the most commonly used moieties to prolong the NPs …

Study Of The Gain-Of-Function Mutant P53 And Parp1 In Triple-Negative Breast Cancer, Devon Lundine

Dissertations, Theses, and Capstone Projects

Cancer cells often lose expression of the p53 protein or express mutant forms of p53. Some of these mutant p53 proteins, called gain-of-function mutant p53, have gained oncogenic functions. Previously, our group observed mutant p53 R273H interacts with replicating DNA and upregulates the chromatin localization of several DNA replication factors including PCNA, MCM2-7, and PARP1 (termed the mtp53-PARP-MCM axis). In this thesis, we explore the contribution of mutant p53 and PARP1 in castration-resistant prostate cancer (mutant p53 P223L and V274F) and triple-negative breast cancer (mutant p53 R273H). In the castration-resistant prostate cancer cell line DU145, we examine two mutant p53 …

Investigation Of Β5 Integrin Function In Epithelial Ovarian Cancer Cell Adhesion And Metastatic Properties Of Spheroids, Dolly Dhaliwal

Electronic Thesis and Dissertation Repository

Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy in the developed world. EOC metastasis is unique since malignant cells detach directly from the primary tumor site into the abdominal fluid and form multicellular aggregates, called spheroids, that possess enhanced survival mechanisms while in suspension. As such, altered cell adhesion properties are paramount to EOC metastasis with cell detachment from the primary tumor, dissemination as spheroids, and reattachment to peritoneal surfaces for secondary tumor formation. These interactions play a crucial role in cell-cell and cell-extracellular matrix interactions, having implications in multiple steps of cancer progression. We previously showed that …

Utilizing Proteolysis-Targeting Chimeras To Target The Transcriptional Cyclin-Dependent Kinases 9 And 12, Hannah King

Theses & Dissertations

Cyclin-dependent kinases (CDKs) are a family of serine-threonine kinases involved in various cellular functions, such as regulating the cell cycle and gene transcription. CDK9, a transcriptional CDK, regulates highly expressed enhancer-associated oncogenic transcription factors, including the oncogene Myc. CDK9 is responsible for the transcription and stabilization of Myc; consequently, it was a validated target for pancreatic cancer treatment.

As such, we developed a panel of aminopyrazole based proteolysis targeting chimera where we identified PROTAC 2 as a selective degrader of CDK9 (DC₅₀ = 158 ± 6 nM). PROTAC 2 was capable of cereblon mediated proteasomal degradation of CDK9 while …

Fgfr4 Glycosylation And Processing In Cholangiocarcinoma Promote Cancer Signaling, Andrew J. Phillips

Theses & Dissertations

Cholangiocarcinoma is a cancer of cholangiocytes, or epithelial cells lining the biliary tract. It is associated with a poor prognosis and additional therapeutic treatments are needed to help patients affected by this disease. Fibroblast growth factor receptor 4 (FGFR4) is receptor tyrosine kinase that is involved in various physiologic and pathologic processes. TCGA analysis of thirty different tumor types showed the highest FGFR4 mRNA levels in cholangiocarcinoma. At the protein level, FGFR4 was observed in the majority of cholangiocarcinomas screened and, higher levels were associated with a poorer prognosis. FGFR4 is an N-linked glycosylated receptor tyrosine kinase that we show …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

The Regulation Of Pannexin1 And Pannexin2 In The Skin In Health And Disease, Rafael E. Sanchez Pupo

Electronic Thesis and Dissertation Repository

Pannexins (PANX1, 2, 3) are a family of channel-forming glycoproteins that mediate intracellular and paracrine signaling. In contrast to PANX2, PANX1 has been extensively investigated in the skin, modulating cell differentiation, wound healing, and melanoma development. PANX1 and PANX2 can co-exist in the same cell and form mixed channels where their glycosylation seems to regulate their intermixing. N-glycosylation and caspase cleavage have been proposed as modulators of the function of PANX1, but their effects on PANX2 are unknown. We explored the PANX2 expression in mouse skin and showed that a Panx2 splice variant (PANX2-202) is continuously expressed throughout aging skin. …

Npsd4: A New Player In Sumo-Dependent Dna Repair, Erin Atkinson

Dissertations & Theses (Open Access)

The human genome is under constant threat from sources of damage and stress. Improper resolution of DNA damage lesions can lead to mutations, oncogene activation, and genomic instability. Difficult-to-replicate-loci present barriers to DNA replication that, when not properly resolved, lead to replication fork stalling and collapse and genomic instability.

DNA damage and replication stress trigger signaling cascades potentiated by multiple types of post-translational modifications, including SUMOylation. Through proteomic analysis of proteins involved in SUMOylation following DNA damage, our lab identified an uncharacterized protein that we named New Player in SUMO-dependent DNA damage repair 4 (NPSD4). Through an additional proteomic screen, …

Targeting Plasma Membrane Phosphatidylserine Content To Inhibit Oncogenic Kras Function, Walaa E. Kattan

Dissertations & Theses (Open Access)

The small GTPase KRAS, which is frequently mutated in human cancers, must be localized to the plasma membrane (PM) for biological activity. We recently showed that the KRAS C-terminal membrane anchor exhibits exquisite lipid-binding specificity for select species of phosphatidylserine (PtdSer). We therefore investigated whether reducing PM PtdSer content is sufficient to abrogate KRAS oncogenesis. Oxysterol-related binding proteins ORP5 and ORP8 exchange PtdSer synthesized in the ER for phosphatidylinositol-4-phosphate (PI4P) synthesized in the PM. We show that depletion of ORP5 or ORP8 reduced PM PtdSer levels, resulting in extensive mislocalization of KRAS from the PM. Concordantly, ORP5 or ORP8 depletion …

Understanding The Pathogenesis Of Renal Medullary Carcinoma, Melinda Soeung

Dissertations & Theses (Open Access)

Renal medullary carcinoma (RMC) is a lethal cancer that predominantly affects young individuals with sickle cell trait (SCT). It is not currently understood why RMC only affects certain individuals with SCT. We found that patients with RMC more frequently participated in high-intensity exercise than matched controls. Using mouse models of SCT, we demonstrated the significant increase of renal hypoxia in the right kidney following high- but not moderate-intensity exercise. We also demonstrated in cell culture studies that SMARCB1 is ubiquitinated for proteasome-mediated degradation in hypoxia, and the re-expression of SMARCB1 leads to compromised proliferation in renal cells specifically in the …