Molecular Biology Commons^™

Suppression Of Chronically Induced Breast Carcinogenesis And Role Of Mesenchymal Stem-Like Cells, Kusum Rathore

Doctoral Dissertations

Sporadic breast cancers are mainly attributable to long-term exposure to environmental factors, via a multi-year, multi-step, and multi-path process of tumorigenesis involving cumulative genetic and epigenetic alterations in the chronic carcinogenesis of breast cells from a non-cancerous stage to precancerous and cancerous stages. Epidemiologic and experimental studies have suggested that various dietary compounds like green tea and grape seed may be used as preventive agents for breast cancer control. In this research, I have developed a cellular model that mimics breast cell carcinogenesis chronically induced by cumulative exposures to low doses of environmental carcinogens. I used the chronic carcinogenesis model …

Definition Of The Landscape Of Chromatin Structure At The Frataxin Gene In Friedreich’S Ataxia, Eunah Kim

Dissertations & Theses (Open Access)

Friedreich’s ataxia (FRDA) is caused by the transcriptional silencing of the frataxin (FXN) gene. FRDA patients have expansion of GAA repeats in intron 1 of the FXN gene in both alleles. A number of studies demonstrated that specific histone deacetylase inhibitors (HDACi) affect either histone modifications at the FXN gene or FXN expression in FRDA cells, indicating that the hyperexpanded GAA repeat may facilitate heterochromatin formation. However, the correlation between chromatin structure and transcription at the FXN gene is currently limited due to a lack of more detailed analysis. Therefore, I analyzed the effects of the hyperexpanded GAA …

The Role Of Receptor Tyrosine Kinase Axl In Pancreatic Ductal Adenocarcinoma And Its Regulation By Hematopoietic Progenitor Kinase 1, Xianzhou Song

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDA) is one of the most aggressive malignancies with less than 5% of five year survival rate. New molecular markers and new therapeutic targets are urgently needed for patients with PDA. Oncogenic receptor tyrosine kinase Axl has been reported to be overexpressed in many types of human malignancies, including diffuse glioma, melanoma, osteosarcoma, and carcinomas of lung, colon, prostate, breast, ovary, esophagus, stomach, and kidney. However, the expression and functions of Axl in PDA are unclear. We hypothesized that Axl contributes to the development and progression of PDA. We examined Axl expression in 54 human PDA samples …

In Vitro Selection Of Aptamers Against Avian Influenza Virus H5n1, Jingjing Zhao

Graduate Theses and Dissertations

Over $10 billion losses in the poultry industry were caused by avian influenza (AI) so far. Rapid and specific detection of avian influenza virus is urgently needed with the concerns over the outbreaks of highly pathogenic H5N1 influenza virus and cases of animal and human infection. Aptamers are oligonucleic acid or peptide molecules that bind a specific target molecule with good affinity. They show better thermal stability than antibodies. The goal of this research was to select DNA-aptamers as the specific recognition element of AI H5N1virus to be used in detection assays specific for field application. In this study, Systematic …

Identification Of Novel Stat3 Target Genes Associated With Oncogenesis, Rachel Haviland

USF Tampa Graduate Theses and Dissertations

Cytokine and growth factor signaling pathways involving STAT3 are frequently constitutively activated in many human primary tumors, and are known for the transcriptional role they play in controlling cell growth and cell cycle progression. However, the extent of STAT3's reach on transcriptional control of the genome as a whole remains an important question. We predicted that this persistent STAT3 signaling affects a wide variety of cellular functions, many of which still remain to be characterized.

We took a broad approach to identify novel STAT3 regulated genes by examining changes in the genome-wide gene expression profile by microarray, using cells expressing …

Downregulation Of Pax2 Suppresses Ovarian Cancer Cell Growth, Huijuan Song

Dissertations & Theses (Open Access)

PAX2 is one of nine PAX genes regulating tissue development and cellular differentiation in embryos. PAX2 promotes cell proliferation, oncogenic transformation, cell-lineage specification, migration, and survival. Unattenuated PAX2 has been found in several cancer types. We therefore sought to elucidate the role of PAX2 in ovarian carcinomas. We found that PAX2 was expressed in low-grade serous, clear cell, endometrioid and mucinous cell ovarian carcinomas, which are relatively chemoresistant compared to high grade serous ovarian carcinomas. Four ovarian cancer cell lines, RMUGL (mucinous), TOV21G (clear cell), MDAH-2774 (endometrioid) and IGROV1 (endometrioid), which express high-levels of PAX2, were used to study the …

The Role Of The Androgen Receptor Cofactor P44/Wdr77 In Astrocyte Activation, Bryce H. Vincent

Dissertations & Theses (Open Access)

Astrogliosis is induced by neuronal damage and is also a pathological feature of the major aging-related neurodegenerative disorders. The mechanisms that control the cascade of astrogliosis have not been well established. In a previous study, we identified a novel androgen receptor (AR)-interacting protein (p44/WDR77) and found that it plays a critical role in the control of proliferation and differentiation of prostate epithelial cells. In the present study, we found that deletion of the p44 gene in the mouse brain caused accelerated aging with dramatic astrogliosis. The p44/WDR77 is expressed in astrocytes and loss of p44/WDR77 expression in astrocytes leads to …

Mechanisms Of Adenovirus-Mediated Autophagy, Erin White

Dissertations & Theses (Open Access)

A patient diagnosed with a glioma, generally, has an average of 14 months year to live after implementation of conventional therapies such as surgery, chemotherapy, and radiation. Glioblastomas are highly lethal because of their aggressive nature and resistance to conventional therapies and apoptosis. Thus other avenues of cell death urgently need to be explored. Autophagy, which is also known as programmed cell death type II, has recently been identified as an alternative mechanism to kill apoptosis- resistant cancer cells. Traditionally, researchers have studied how cells undergo autophagy during viral infection as an immune response mechanism, but recently researchers have discovered …

Mechanism Of Transcriptional Suppression Of A Phytochrome A Epiallele In Arabidopsis Thaliana, Gulab D. Rangani

Graduate Theses and Dissertations

Cytosine methylation in DNA is an integral part of epigenetically controlled regulatory networks in eukaryotes. Both plants and vertebrates display DNA methylation in the gene coding region; however, its role in gene expression is not well understood. Gene promoter, on the other hand, remains largely unmethylated. Acquisition of methylation in promoter results in transcriptional suppression of the gene. The goal of this research is to study the effect of coding region methylation in gene expression using a unique gene model, phyA'. phyA' is a transcriptionally suppressed epiallele of the Arabidopsis thaliana Phytochrome A gene, which contains methylation in CG sites …

Developmental Deregulation And Tumorigenesis Inhibition In 14-3-3zeta Knockout Mouse, Jun Yang

Dissertations & Theses (Open Access)

Cancer is second leading cause of death in the United States. Improving cancer care through patient care, research, education and prevention not only saves lives, but reduces health care cost as well. Breast cancer is the most leading cause of cancer incidence and cancer related death in women of the United States. 14-3-3s are a family of conserved proteins ubiquitously expressed in all eukaryotic organisms. They form complexes with hundreds of proteins by binding to specific phospho-serine/threonine containing motifs. In this way they regulate a variety of cellular processes and are involved in many human diseases especially cancer to our …

The Role Of Cancer-Associated Fibroblasts In Lung Tumorigenesis, Jonathon D. Roybal

Dissertations & Theses (Open Access)

The extracellular milieu is rich in growth factors that drive tumor progression,but the mechanisms that govern tumor cell sensitivity to those ligands have notbeen fully defined. In this study, we address this question in mice that developmetastatic lung adenocarcinomas through the suppression of the microRNA-200 (miR-200) family. Cancer-associated fibroblasts (CAF) enhance tumorgrowth and invasion by secreting VEGF-A that binds to VEGFR1, a processrequired for tumor growth and metastasis in mice and correlated with a poorprognosis in lung adenocarcinoma patients. In this study, we discovered thatmiR-200 blocked CAF-induced tumor cell invasion by directly targetingVEGFR1 in tumor cells. In the context of …

Nanosecond Pulsed Electric Field Induction Of Programmed Cell Death Is Cell Type Dependent: An In Vitro Study, Wei Ren

Theses and Dissertations in Biomedical Sciences

Nanosecond pulsed electric fields (nsPEFs) present a novel and effective method for cancer ablation by eradicating the ubiquitous cancer hallmark of apoptosis evasion and enforcing cancer programmed cell death. To develop nsPEFs as an anticancer method, a comprehensive understanding of cell death mechanisms is required. The overall objective of this dissertation is to elucidate molecular mechanisms underlying effects of nsPEFs on E4 murine squamous cell carcinoma and human T-cell Jurkat clones that are wildtype, deficient in FADD (ΔFADD) and deficient in caspase-8 (ACas-8). The overall hypothesis is that nsPEFs eliminate cancer cells through activating caspase-dependent and caspase-independent programmed cell death …

A Novel Function For Aurora B Kinase In The Regulation Of P53 By Phosphorylation, Chris P. Gully

Dissertations & Theses (Open Access)

The mitotic kinase Aurora B plays a pivotal role in mitosis and cytokinesis and governs the spindle assembly checkpoint which ensures correct chromosome segregation and normal progression through mitosis. Aurora B is overexpressed in breast and other cancers and may be an important molecular target for chemotherapy. Tumor suppressor p53 is the guardian of the genome and an important negative regulator of the cell cycle. Previously, it was unknown whether Aurora B and p53 had mutual regulation during the cell cycle. A small molecule specific inhibitor of Aurora B, AZD1152, gave us an indication that Aurora B negatively impacted p53 …

The Role And Mechanism Of The Homeobox Gene Dlx4 In Transforming Growth Factor-B Resistance In Cancer, Bon Q. Trinh

Dissertations & Theses (Open Access)

Transforming growth factor-b (TGF-b) is a cytokine that plays essential roles in regulating embryonic development and tissue homeostasis. In normal cells, TGF-b exerts an anti-proliferative effect. TGF-b inhibits cell growth by controlling a cytostatic program that includes activation of the cyclin-dependent kinase inhibitors p15^Ink4B and p21^WAF1/Cip1 and repression of c-myc. In contrast to normal cells, many tumors are resistant to the anti-proliferative effect of TGF-b. In several types of tumors, particularly those of gastrointestinal origin, resistance to the anti-proliferative effect of TGF-b has been attributed to TGF-b receptor or Smad mutations. However, these mutations are absent from many …

Ancient Mitochondrial Dna From Pre-Historic Southeastern Europe: The Presence Of East Eurasian Haplogroups Provides Evidence Of Interactions With South Siberians Across The Central Asian Steppe Belt, Jeremy R. Newton

Masters Theses

Studies of mitochondrial DNA (mtDNA) polymorphism have provided valuable insights for understanding patterns of human migration and interaction. The ability to recover ancient mtDNA sequence data from post-mortem bone and tissue samples allows us to view snapshots of historic gene pools firsthand, provided that great care is taken to prevent sample contamination. In this study, we analyzed the DNA sequence of the first hypervariable segment (HVSI) of the mtDNA control region, as well as a portion of the coding region, in 14 individuals from three collective burials from the Neolithic Dnieper-Donetz culture and three individuals from Bronze Age Kurgan burials, …

The Role Of Bacteriocins In Mediating Interactions Of Bacterial Isolates From Cystic Fibrosis Patients, Emine Suphan Bakkal

Open Access Dissertations

Cystic Fibrosis (CF) is a common autosomal genetic disorder in Caucasian populations. CF is caused by mutations in the cftr gene, which encodes the CF transmembrane conductance regulator (CFTR). CFTR regulates chloride and sodium ion transport across the epithelial cells lining the exocrine organs. Mutations in the cftr result in a failure to mediate chloride transport, which leads to dehydration of the mucus layer surrounding the epithelial cells. The mucus coating in the lung epithelia provides a favorable environment for invasion and growth of several opportunistic bacterial pathogens resulting in life threatening respiratory infections in CF patients. Pseudomonas aeruginosa(Pa) and …

Xenopus Adam13 And Adam19 Are Important For Proper Convergence And Extension Of The Notochord, Russell David Neuner

Open Access Dissertations

Gastrulation is a fundamental process that reorganizes the primary germ layers to shape the internal and external features of an early embryo. Morphogenetic movements underlying this process can be classified into a variety of different types of cellular movements. I will focus on investigating in this thesis two types of cell movements in the dorsal mesoderm; mediolateral cell intercalation and convergence and extension. During gastrulation, mesoderm cells send protrusions to gain traction on neighboring cells and the surrounding extracellular matrix; a process called mediolateral cell intercalation. Mesoderm cells use this type of cell movement to converge and extend the dorsal …

Cooperative And Antagonistic Roles For Heterochromatin Proteins In Transcriptional Regulation Of The Drosophila Sex Determination Masterswitch Gene, Hui Li

University of Kentucky Doctoral Dissertations

HOAP was originally identified as a component of an ORC-containing multi-protein complex of Heterochromatin Protein 1 (HP1) from early Drosophila embryos. HOAP immunostaining showed prominent association of it with telomeres, and mutants for HOAP (cav¹) showed it functions along with HP1 in forming a telomere capping complex that prevents telomeric fusions.

Weaker HOAP immunostaining is also observed in regions of pericentric heterochromatin and euchromatin. To examine the role of HOAP at these non-telomeric sites, we applied Affymetric Drosophila Genome Arrays to undertake a microarray expression profiling study of genes that are mis-expressed in cav¹ mutant larvae. The …

Cardiac Calsequestrin Phosphorylation And Trafficking In The Mammalian Cardiomyocyte, Timothy Mcfarland

Wayne State University Dissertations

Cardiac CSQ (CSQ2) is a multifaceted protein, capable of binding significant quantities of Ca2+ and altering ryanodine receptor activity at the junctional sarcoplasmic reticulum (SR). Little is known about the trafficking of CSQ2 from its unknown site of biosynthesis, which appears to be of importance as its structure changes in a trafficking-dependent manner in various types of heart failure. Through the use of multiple antibodies specific to classic rough ER markers, and with the creation of CSQ-DsRed tetramer fusion protein, we were able to establish a juxtanuclear localization of rough ER in cardiomyocytes. Using fluorescence confocal microscopy, the translocon complex …

Identification And Characterization Of Fkbp52-Specific Inhibitors For The Treatment Of Prostate Cancer, Johanny Tonos De Leon

Open Access Theses & Dissertations

Steroid hormone receptors require the ordered assembly of various chaperone and cochaperone proteins in order to reach a functional state. The final stage in the receptor maturation process requires the formation of a mutimeric complex consisting of Hsp90 dimer, p23, and one of several large immunophilins. Studies conducted previously demonstrated that the large immunophilin FKBP52 acts to potentiate glucocorticoid, androgen, and progesterone receptor signaling pathways. The aim of these studies was to identify and characterize FKBP52-specific inhibitors that would not only serve as tools for the pharmacological analysis of FKBP52-receptor interactions, but may also lead to novel drugs with significant …

Understanding The Origins, Dispersal, And Evolution Of Bonamia Species (Phylum Haplosporidia) Based On Genetic Analyses Of Ribosomal Rna Gene Regions, Kristina M. Hill

Dissertations, Theses, and Masters Projects

No abstract provided.

Inhibition Of P53 Dna Binding Function By The Mdm2 Acidic Domain, Brittany Lynne Cross

USF Tampa Graduate Theses and Dissertations

MDM2 regulates p53 predominantly by promoting p53 ubiquitination. However, ubiquitination-independent mechanisms of MDM2 have also been implicated. Here we show that MDM2 inhibits p53 DNA binding activity in vitro and in vivo. MDM2 binding promotes p53 to adopt a mutant-like conformation, losing reactivity to antibody Pab1620, while exposing the Pab240 epitope. The acidic domain of MDM2 is required to induce p53 conformational change and inhibit p53 DNA binding. ARF binding to the MDM2 acidic domain restores p53 wild type conformation and rescues DNA binding activity. Furthermore, histone methyl transferase SUV39H1 binding to the MDM2 acidic domain also restores p53 wild …

From Dna To Protein: A Study Of Genomic Instability Candidate Genes During Zebrafish Development, Kristine Griffett

USF Tampa Graduate Theses and Dissertations

The zebrafish, Danio rerio, is a type of freshwater minnow often used to model human diseases including cancer, anxiety and aging diseases. The overall biology of zebrafish is strikingly similar to that of humans, allowing these fish to be used for drug discovery and toxicology studies for preclinical trials. In this study, zebrafish embryos were used to identify and characterize several candidate genes within two known regions of genomic instability on chromosome 18 and chromosome 4. This fish that were used in this study had been previously classified as genomic instability (gin) mutants due to increased incidence of somatic mutation …

Human Trophoblast Survival And Invasion In The Developing Placenta: Autocrine Regulation By Hbegf, Philip Jessmon

Wayne State University Dissertations

HBEGF is a multifunctional protein in early pregnancy that induces cytotrophoblast (CTB) cell differentiation to an invasive phenotype, protects against apoptosis, and is involved in an autocrine signaling mechanism that leads to its own protein synthesis. CTBs exist in a low O₂ environment during the first 10 weeks of implantation, during which they invade the decidualized uterine stroma. Inhibitors of intracellular signaling pathways demonstrated that at 20% O₂ HBEGF induces an increase in cell migration through the ERK, MAPK14, JNK, or PIK3 pathways downstream of signaling through its ERBB receptors. Also downstream of these four pathways, HBEGF induces …

Palmitoylation And The Yeast Casein Kinase Yck2, Irene Papanayotou

Wayne State University Dissertations

Palmitoylation is a post-translational lipid modification that allows proteins to interact with membranes. In the yeast Saccharomyces cerevisiae, the casein kinase Yck2 is palmitoylated twice at its two C-terminal palmitoyl-accepting cysteine residues, by the palmitoyl-transferring enzyme Akr1. Once palmitoylated, Yck2 traffics through the well characterized secretory pathway to the plasma membrane where it participates in many cellular functions, including bud morphogenesis, cytokinesis, nutrient sensing, and receptor internalization. While the hydrophilic Yck2 is presumably synthesized on cytosolic ribosomes, it gains access to the membrane system by interaction with the six transmembrane-spanning Golgi-localized Akr1. Since palmitoylation occurs at membranes and the palmitoyl-transferases …

Amphiregulin (Areg) And Epidermal Growth Factor (Egf): Disparate In Egfr Signaling And Trafficking, Andrea Jacqueline Baillo

Wayne State University Dissertations

We have previously shown that SUM-149 human breast cancer cells require an AREG/EGFR autocrine loop for cell proliferation. We also demonstrated that AREG can increase EGFR stability and promote EGFR localization to the plasma membrane. In the presented dissertation we successfully knocked-down AREG expression in SUM-149 cells by lenti-viral infection of AREG shRNA. In the absence of AREG expression, SUM-149 cell growth was slowed, but not completely inhibited. Furthermore, cells infected with AREG shRNA constructs showed an increase in EGFR protein expression by western blot. Immunofluorescence and confocal microscopy showed that following AREG knock-down, EGFR continued to localize to the …

The Role Of The Sparc Acidic Domain And Egf-Like Module In Glioma Migration, Invasion, And Signaling, Heather M. Mcclung

Wayne State University Dissertations

THE ROLE OF THE SPARC ACIDIC DOMAIN AND EGF-LIKE MODULE IN GLIOMA MIGRATION, INVASION, AND SIGNALING

HEATHER M. MCCLUNG

Advisor: Sandra A. Rempel, Ph.D.

Major: Pharmacology

Degree: Doctor of Philosophy

We have previously shown that Secreted Protein Acidic and Rich in Cysteine (SPARC) is upregulated in all astrocytoma grades and increases tumor cell migration and invasion. It is thought that different domains within the protein may regulate SPARC functions, suggesting domain-specific targeting to inhibit invasion. To enhance our understanding of SPARC-mediated invasion, we first confirm, at the protein level, our previous cDNA array results, that SPARC increases expression of the …

Frazzled And Abelson Interact To Regulate The Actin Cytoskeleton In Drosophila, Bridget Elsa Varughese

Wayne State University Dissertations

Guidance receptors such as Frazzled affect cell shape and motility by directly or indirectly modulating the cytoskeleton. Fra is particularly needed for the formation of the posterior commissures in a developing Drosophila embryo. The cytoplasmic tyrosine kinase, Abelson Kinase (Abl) enhances the loss of commissures observed in fra mutant. Abl physically interacts with Frazzled to help guide commissural axons across the midline. Furthermore, the loss of commissural axons is only seen when the actin dynamics are perturbed. Abl is also known to regulate actin-dependent processes underlying formation of filopodia, microspikes and membrane ruffles. So, we established a Drosophila S2 cell …

Regulation Of The Aryl Hydrocarbon Receptor And The Signal Transducer And Activator Of Transcription 1 By Long-Term Estrogen Exposure In Breast Carcinoma Cells, Neal Englert

Legacy Theses & Dissertations (2009 - 2024)

The risk of developing breast cancer is known to be associated with a woman's lifetime exposure to estrogens, both endogenous and exogenous. Increased exposure to estrogens stimulates cellular proliferation, which is a widely accepted theory of estrogen receptor positive mammary carcinogenesis. The molecular mechanisms of gene expression regulation in response to long-term estrogen exposure (LTEE) of MCF-7 breast cancer cells were addressed in this study, with a focus on the aryl hydrocarbon receptor (AHR) and signal transducer and activator of transcription 1 (STAT1).

The Role Of Trm9 In Stress Responses, Ashish Ravindra Patil

Legacy Theses & Dissertations (2009 - 2024)

Cells need to respond appropriately to environmental changes in order to maintain homeostasis. The cellular response to an environmental stress is regulated at transcriptional, translational and post translational levels. The tRNA, which acts as an adaptor molecule between the mRNA and the protein, plays an important role in the translational regulation of cellular responses to stress and is one of the most heavily modified biomolecules. In Saccharomyces cerevisiae , the wobble uracil of the tRNA(3'-UCU-5') Arg, tRNA(3'-UUC-5') Glu and certain other specific tRNAs are modified to 5-methoxycarbonylmethyluridine (mcm5U) and 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U) residues by the tRNA methyltransferase 9 (Trm9). Modifications at …