Cancer Biology Commons^™

Anti-Tumor Functions Of Sphingosine Kinase 1 And Sphingosine Kinase 2 In Breast Cancer Development, Melissa A. Maczis

Theses and Dissertations

Bioactive sphingolipid metabolite sphingosine-1‐phosphate (S1P) circulating levels have been implicated in breast cancer (BC) progression. BCs usually respond to 17β-Estradiol (E2) through canonical receptor ERα66 for genomic effects, however, E2 also triggers rapid, non-genomic responses. E2 has been shown to activate sphingosine kinase 1 (SphK1), increasing S1P for S1P receptors signaling important for BC. The E2 receptor activating SphK1 has not been identified. We demonstrate triple negative BC cells, expressing only novel ERα splice variant ERα36, E2-induced SphK1 activation for S1P secretion. Tamoxifen, first-line BC endocrine therapy, an ERα66 antagonist but ERα36 agonist, activates SphK1 and increases S1P secretion in …

Optimisation Of Estrogen Receptor Subtype-Selectivity Of A 4-Aryl-4h-Chromene Scaffold Previously Identified By Virtual Screening, Miriam Carr, Andrew Knox, Daniel Nevin, Niamh O'Boyle, Shu Wang, Billy Egan, Thomas Mccabe, Brendan Twamley, Daniela Zisterer, David Lloyd, Mary Meegan

Articles

4-Aryl-4H-Chromene derivatives have been previously shown to exhibit anti-proliferative, apoptotic and anti-angiogenic activity in a variety of tumor models in vitro and in vivo generally via activation of caspases through inhibition of tubulin polymerisation. We have previously identified by Virtual Screening (VS) a 4-aryl-4H-chromene scaffold, of which two examples were shown to bind Estrogen Receptor α and β with low nanomolar affinity and <20-fold selectivity for α over β and low micromolar anti-proliferative activity in the MCF-7 cell line. Thus, using the 4-aryl-4H-chromene scaffold as a starting point, a series of compounds with a range of basic arylethers at C-4 and modifications at the C3-ester substituent of the benzopyran ring were synthesised, producing some potent ER antagonists in the MCF-7 cell line which were highly selective for ERα (compound 35; 350-fold selectivity) or ERβ (compound 42; 170-fold selectivity).

Brca1 & Ctdp1 Brct Domainomics In The Dna Damage Response, Kimiko L. Krieger

Theses & Dissertations

Genomic instability is one of the enabling characteristics of cancer. DNA damage response pathways are important for genomic integrity and cell cycle progression. Defects in DNA damage repair can often lead to cell cycle arrest, cell death, or tumorigenesis. The activation of the DNA damage response includes tightly regulated signaling cascades that involve kinase phosphorylation and modular domains that scaffold phosphorylated motifs to coordinate recruitment of DNA repair proteins. Modular domains are conserved tertiary structures of a protein that can fold, function, and evolve independently from an intact protein. One of the most common modular domains involved in DNA damage …

Hdac1 Is A Required Cofactor Of Cbfβ-Smmhc And A Therapeutic Target In Inversion 16 Acute Myeloid Leukemia, Lisa E. Richter

Theses & Dissertations

Acute myeloid leukemia (AML) is a neoplastic disease characterized by the uncontrolled proliferation and accumulation of immature myeloid cells. A common mutation in AML is the inversion of chromosome 16 [inv(16)], which generates a fusion between the genes for core binding factor beta (CBFB) and smooth muscle myosin heavy chain (MYH11), forming the oncogene CBFB-MYH11. The expressed protein, CBFβ-SMMHC, forms a heterodimer with the key hematopoietic transcription factor RUNX1. Although CBFβ-SMMHC was previously thought to dominantly repress RUNX1, recent work suggests that CBFβ-SMMHC functions together with RUNX1 to activate transcription of specific target genes.

Targeting the …

The Role Of Reactive Oxygen Species In Regulating Macrophage And Fibroblast Activation Within The Breast Cancer Tumor Microenvironment, Brandon J. Griess

Theses & Dissertations

The tumor microenvironment (TME) is a key determining factor in breast cancer, especially the more aggressive subtype triple negative breast cancer (TNBC). The activated fibroblasts and macrophages within the TME have many tumor promoting functions. Therefore, targeting their activation presents a novel therapeutic approach in TNBC. My work studied the role of reactive oxygen species (ROS) during fibroblast and macrophage activation in breast cancer.

My studies showed that expression of the secreted antioxidant enzyme, EcSOD, is silenced in breast cancer samples, in part, via increased promoter methylation. The re-expression of EcSOD inhibited c-Met activation in the TNBC cell line, MDA-MB231. …

Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich

Biomedical Sciences ETDs

Salivary gland adenoid cystic carcinoma (ACC) is an aggressive tumor with a tendency to infiltrate surrounding nerves and metastasize to distant sites. The standard treatment often fails to control local tumor recurrence and distant metastases and no approved targeted therapeutic options exist for these tumors. The goal of our studies was to reveal the molecular mechanisms driving ACC tumor development and novel drug targets to improve patient morbidity and mortality.

We first analyzed clinical and RNA-sequencing (RNA-seq) data for 68 formalin-fixed paraffin-embedded (FFPE) ACC tumor samples and described previously unappreciated molecular heterogeneity that predicts patient outcome. The poor outcome subgroup …

Discovery Of An Egfr Inhibitor For The Treatment Of Lung And Other Cancers, Jodie Meng '20

Student Publications & Research

The Epidermal Growth Factor Receptor (EGFR), a transmembrane protein involved in the regulation of signaling pathways, is frequently overexpressed in epithelial tumors. First generation EGFR TKIs, such as erlotinib and gefitinib, traditionally improved outcomes for non-small-cell lung carcinoma and pancreatic cancer patients by attaching competitively and reversibly to the ATP binding domain of EGFR. Second-generation EGFR TKIs have been developed to combat resistance among patients, despite demonstrating toxic side effects. In the present study, 1400 selective inhibitors were designed based on the molecular scaffolds of first and second generation EGFR TKIs. Results were refined by parameters outlined in Lipinski’s rule. …

Immediate-Early Genes And Delayed Primary Response Genes Regulated By Nmu In Skbr3 Her-2 Positive Breast Cancer Cell Line, Jessica Murphy, Sweta Rani

SURE Journal: Science Undergraduate Research Experience Journal

Background
Breast cancer is a heterogeneous disease that consists of varying genetic, cellular and molecular subtypes with unique characteristics. Due to the multiple subtypes and molecular markers of breast cancer, successful clinical treatment is hampered by the lack of reliable biomarkers. HER2-positive breast cancer is an aggressive subtype associated with poor patient prognosis. Although survival rates have dramatically increased due to the development of Trastuzumab in 1997, many patients develop a resistance to this therapeutic treatment and relapse over time. Rani et al. (2014), have associated the acquirement of resistance to HER2-treatment with Neuromedin U, but the mechanisms by …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

Deubiquitinating Enzymes Promote Cancer Progression And Metastasis Via Regulating Protein Stability, Zhenna Xiao

Dissertations and Theses (Open Access)

Deubiquitinating enzymes (DUBs, also called deubiquitinases) are enzymes that remove monoubiquitin or polyubiquitin chains from target proteins. DUBs have critical roles in cell homeostasis and signal transduction, as they regulate protein degradation, subcellular localization, and protein-protein interaction. Deregulation of DUBs contributes substantially to tumor formation and progression, and therefore targeting DUBs may be a promising cancer therapy strategy. My dissertation focuses on identifying the DUBs of EZH2 and SNAI1, two proteins critical for cancer progression and metastasis, and establishing these DUBs as promising anti-cancer targets.

EZH2, the catalytic component of the PRC2 complex, silences gene transcription by histone methylation. High …

A High Throughput Assay For The Detection Of Stimulator Of Interferon Genes (Sting) Agonists, Michael J. Ingling

Graduate School of Biomedical Sciences Theses and Dissertations

The innate immune system includes a menagerie of different cell types, each with a different role in the process of monitoring the body for invaders and presenting gathered debris (antigen) to the adaptive immune system. Somatic cells have intracellular receptors for the same purpose. Cancer cells, however, have avoided these methods of detection despite, in many cases, the tumor’s immunogenic traits. Immuno-oncology is a field dedicated to the immunological traits of tumors, more recently finding ways of instigating an immune response against tumors. In this regard, STING, a receptor of cyclic dinucleotides (CDN), has come to the forefront of immuno-oncology. …

In Vitro Evaluation Of Ovarian Cancer Tumorigenesis As A Function Of Quinone Oxidoreducatse-1 And Cell Phenotype, Milcah S. Jackson

LSU Doctoral Dissertations

In vitro multicellular spheroids are attractive model systems for assessing genetic and epigenetic changes that occur in diseased tissues. Understanding how such alterations in gene and subsequent protein expression affect disease progression and metastasis, drug resistance, and recurrence is of great interest in cancer research. In this regard, examining expression and activity of proteins, such as those with cytoprotective ability that are overexpressed in cancer cells, in addition to cell phenotype (i.e., stem-like, epithelial, mesenchymal, or mixed), are two ways to evaluate genetic and epigenetic changes. Moreover, determining the impact that cytoprotective proteins and cell phenotype have on tumor formation …

Targeted Genome-Scale Gene Activation And Gene Editing In Human Cells To Understand Disease Models, Michael De La Cruz

KGI Theses and Dissertations

Since the discovery of sequence directed DNA editing reagents such as CRISPR-Cas9 RNA-guided and TALEN DNA endonucleases, there has been a snowball of advances in the life sciences due to the ability to efficiently edit and control genomes within living cells. CRISPR-Cas9 based genomic tools, which facilitate the high-throughput precise manipulation of genes, allow for unbiased functional genomic screens. We used a human CRISPR-Cas9 Synergistic Activation Mediator pooled library which utilizes an engineered protein complex for transcriptional activation of 23,430 endogenous genes to investigate the development of novel resistance mechanisms to lung cancer targeted therapy, Erlotinib. We set out to …

Identification Of Pathways Required For The Survival Of Inversion(16) Acute Myeloid Leukemia, Yiqian Wang

Theses & Dissertations

Inversion of chromosome 16 [inv(16)] acute myeloid leukemia (AML) generates a fusion gene CBFB-MYH11. Approximately half of inv(16) AML patients eventually relapse mainly due to the existence of leukemia stem cells (LSCs). Previous work using a Cbfb-MYH11 knockin mouse model showed that the LSCs are enriched within CSF2RB^- population. Another gene upregulated by Cbfb-MYH11 encodes the cytokine receptor IL1RL1. Using Cbfb-MYH11 knockin mice, we showed that LSCs exist in multiple sub-populations defined by their immunophenotype, and IL1RL1 is expressed by cell populations with high LSC activity. We also found that treatment of IL-33, the ligand for IL1RL1, promoted …

The Role Of Ros In The Progression And Treatment Of Castration-Resistant Prostate Cancer, Dannah R. Miller

Theses & Dissertations

Prostate cancer is the second leading cause of cancer-related deaths in U.S. men, primarily due to the development of castration-resistant (CR) prostate cancer (PCa), of which there are no effective treatment options. Reactive oxygen species (ROS) plays a critical role in prostate carcinogenesis, including the progression of the CR PCa phenotype. ROS regulates both cell proliferation and apoptosis; a moderate increase in ROS can promote proliferation; however, a substantial rise in ROS levels will result in apoptosis. Oxidase p66Shc is elevated in clinical PCa cells and has been associated with a metastatic phenotype of CR PCa cells, promoting PCa cell …

Developing Targeted Therapy Against Pancreatic Cancer, Garima Kaushik

Theses & Dissertations

Not available.

A Dedicated Chaperone Mediates The Safe Transfer Of Mitoribosomal Proteins To Their Site Of Assembly, Gabrielle Ashley Hillman

Graduate School of Biomedical Sciences Theses and Dissertations

Mitochondrial ribosomes are functionally specialized for the synthesis of several essential inner membrane proteins of the respiratory chain. While remarkable progress has recently been made towards understanding the structure of mitoribosomes, the unique pathways and factors that facilitate their biogenesis remain largely unknown. This dissertation defines the physiological role of an evolutionarily conserved yeast protein called Mam33 in mitochondrial ribosome assembly. The biomedical relevance of this finding stems from the fact that mutations or changes in its expression of the human ortholog p32 result in mitochondrial dysfunction. In human patients, bi-allelic mutations cause severe multisystemic defects in mitochondrial energy metabolism, …

Paraoxonase 2 Is Critical For Non-Small Cell Lung Carcinoma Proliferation., Aaron Whitt

Electronic Theses and Dissertations

Non-small cell lung carcinoma (NSCLC) comprises 85% of lung cancer diagnoses and is plagued by drug resistance. Thus, elucidating the underlying mechanisms of NSCLC is paramount to expand future treatment options. Paraoxonase 2 (PON2), an intracellular enzyme with arylesterase and lactonase functions, has well-established anti-atherosclerotic activity. Recent studies show PON2 is overexpressed in a variety of tumors and confers drug resistance, although these interactions have not been thoroughly examined in NSCLC. Thus, we sought to investigate the role of PON2 in cellular proliferation using PON2-knockout mice, primary mouse cells, and NSCLC cell lines. Using these approaches, we demonstrate that PON2 …

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims …

Cellular Localization Of Rad51d Mutant Proteins And The Application Of Art To Increase Scientific Literacy In America, Claire L. Chabot

Senior Theses

Ovarian cancers are the leading cause of death from cancer of the female reproductive system. Approximately 50% of ovarian cancers have defects in the homologous recombination (HR) DNA repair pathway that is required for the repair of DNA double-stranded breaks. The status of HR genes, such as BRCA1, BRCA2, and the RAD51 family, contributes to ovarian cancer development as well as treatment decisions regarding chemotherapy, radiation, and immunotherapy. The overarching goal of this project is to identify new insights into HR that can integrate with Precision Medicine Initiatives and align with the goals of the Cancer Moonshot 2020 Program. I …

Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey

Biology ETDs

Properly executed cell division is crucial to development, maintenance, and longevity of multicellular organisms. Defects in both symmetric and asymmetric divisions can lead to improper developmental patterning, as well as genomic instability, disruption of tissue homeostasis, and cancer. Our research focuses on how regulators orchestrate proper cell divisions. Mushroom Body Defect (Mud) is one such regulator, and here we describe how Mud is regulated via the Hippo signaling pathway kinase Warts (Wts), showing Wts phosphorylates Mud to enhance interaction with the polarity protein Partner of Inscuteable, promoting spindle orientation activity. We next focus on another regulator, Shortstop (Shot), describing a …

The Functional Role Of Rna Binding Protein Rbms3 As A Tumor Promoter In Triple-Negative Breast Cancer Cells, Yuting Zhou

Theses and Dissertations--Molecular and Cellular Biochemistry

RBMS3 belongs to the family of c-myc gene single-strand binding proteins (MSSPs) that play important roles in transcriptional regulation. Here, we show that RBMS3 functions as a tumor promoter in triple-negative breast cancer (TNBC), a highly aggressive BC subtype. Analysis of RBMS3 expression shows that RBMS3 is upregulated at both mRNA and protein levels in TNBC cells. Functionally, overexpression of RBMS3 increases cell migration, invasion and cancer stem cell (CSC) behaviors. Moreover, RBMS3 induces expression of epithelial-mesenchymal transition (EMT) and CSC markers. Conversely, loss of RBMS3 in TNBC BT549 cells inhibits cell proliferation, migration and mesenchymal phenotype. Correlation analysis shows …

Characterizing Chromosomal Aberrations In Cells Deficient For Both Atm And Msh2, Yeliz Inalman

Dissertations and Theses

Ataxia telangiectasia mutated (ATM) and mutS homologue 2 (MSH2) are important DNA repair proteins that participate in DNA repair pathways to maintain genomic integrity. Mice deficient for ATM and MSH2 mice are viable. However, ATM^-/- mice show growth retardation, neurological defects, and spontaneous lymphomagenesis. MSH2^-/- mice suffer from aggressive lymphoid tumors between two to five months of age and have increased microsatellite instability, which predisposes MSH2^-/- mice to carcinomas. However, mice deficient in both ATM and MSH2 are unable to survive beyond postnatal day 21 (P21). The observed lethality in ATM^-/-MSH2^-/- mice may result …

Regulation Of The Long Non-Coding Rna Fam83h-As1 By Human Papillomavirus In Cervical Cancer, Jamie Ann Barr Ph.D.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Non-coding RNAs (NcRNAs), such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been found to be involved in a variety of critical biological processes, and dysregulation of ncRNAs have been involved with several human diseases including cancer.

High-risk human papillomavirus (HPV) infection is one of the first events in the process of carcinogenesis in cervical and a subset of head and neck cancers. The expression of the viral oncoproteins E6 and E7 is essential in this process by inactivating the tumor suppressor proteins p53 and Rb, respectively, in addition to their interactions with other host proteins and regulation of …

Investigation Of The Interactions Between The Dream Complex And Hpv16, Kevin Ko

Theses and Dissertations

According to the American Cancer Society, it has been estimated that in 2019 alone, there will be approximately 53,000 new cases of oropharyngeal cancers. Oropharyngeal cancers are the largest subset of head and neck squamous cell carcinomas (HNSCCs), which are the sixth most common cancer across worldwide populations. They, along with other HNSCCs, fall under a category of cancers known as Human papillomavirus (HPV)-associated cancers, and it has been found that upwards of 70% of these cancers can be attributed to high-risk HPV infections.

Specifically, the high-risk HPV gene, E7, plays a key role in relieving cell cycle repression by …

Eralpha Isoforms Modulate The Tumorigenicity Of 24r,25(Oh)2d3 In Estrogen-Responsive Cancer, Anjali Verma

Theses and Dissertations

Over 200,000 cases of breast cancer are diagnosed every year. Nearly 20% of these patients supplement their diets with some form of vitamin D. This high frequency of vitamin D supplement use may be due in part to research suggesting that cancer patients with higher serum vitamin D₃ levels have better prognoses than patients with low serum vitamin D_3. However, double-blind clinical trials on the efficacy of vitamin D₃ supplementation in breast cancer have been inconclusive. A recent meta-analysis showed evidence of reduced cancer recurrence in patients taking vitamin D₃ supplements who had ‘estrogen receptor positive’ …

Cyclophilin A As A Molecular Switch Regulating Prolactin Receptor Mediated Signaling, Mammary Tumorigenesis And Metastasis, Shawn Hakim

Theses and Dissertations

Prolactin (PRL) and its receptor (PRLr) have been implicated in the development and progression of human breast cancer. PRL activates its receptor and induces activation of proximal Janus kinase 2 (Jak2) for signal transduction. Here, we sought to determine the role of PRLr-associated peptidyl-prolyl isomerase, cyclophilin A (CypA), in modulating structure/function relationships of the PRLr. It was demonstrated that CypA mediated PRL-induced conformational change of the CFP- and -YFP tagged forms of the PRLr cytoplasmic-tail, whereas CypA inhibition by NIM811 (N-methyl-4-isoleucine cyclosporin) or knockdown blocked the conformational change of the PRLr assessed by Fluorescence Resonance Energy Transfer (FRET) signal or …

Delineation Of New Mechanisms Of Dna Double Strand Break Repair, Songli Zhu

Theses & Dissertations

DNA damage is frequently induced in cells by both endogenous and exogenous agents. DNA damage, particular double strand breaks (DSBs) may lead to genomic instability, and the progression of cancer, aging, neurodegeneration, and other human diseases. The cell employs two major DSB repair pathways, including homologous recombination (HR) and Non-homologous end joining (NHEJ), but the detailed mechanisms of DSB repair remain to be further revealed.

In the first part of this study, we characterized a plasmid-based assay to investigate NHEJ repair in Xenopus egg extracts. Our data argued for a preference for the precise repair by the NHEJ machinery and …

Role Of P300 Zz Domain In Chromatin Association And Histone Acetylation, Yongming Xue

Dissertations and Theses (Open Access)

Transcription is strictly regulated by numerous factors including transcription coactivators. The p300 protein and its close paralogue CREB-binding protein (CREBBP, aka CBP) are well-known transcriptional coactivators that have intrinsic lysine acetyltransferase activity. The functions of p300/CBP largely rely on their capabilities to bind to chromatin and to acetylate the histone substrates. However, the molecular mechanisms underlying the regulation of these processes are not fully understood.

Through combination of various biochemical, biophysical and molecular approaches, we show that the ZZ-type zinc finger (ZZ) domain of p300 functions as a histone reader that specifically binds the N-terminal tail of histone H3. Crystal …

Development Of A Pd-L1 Pet Imaging Biomarker, Caleb Jack Bridgwater

Posters-at-the-Capitol

Immunotherapy strategies are very promising treatments for cancer patients. Specifically, Immune checkpoint inhibitor therapy focusing on the PD-1/PD-L1 pathway shows long-lasting positive results in many cancer patients. Unfortunately, not all the patients can benefit from this highly effective treatment. Hence, there is a great need for predictive biomarkers. Immunohistochemical (IHC) staining has been used as a way of predicting patient response, yet shows many problems. For example, IHC utilizes an invasive biopsy and sample fixing, which creates an incomplete and delayed picture of the patient’s biochemistry and the tumor microenvironment, consequently ignoring metastases.

The purpose of this study is to …