Cell and Developmental Biology Commons^™

A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani

Honors Scholar Theses

Bacteria, such as Escherichia coli, have an inducible system in response to DNA damage termed the SOS response. This system is activated when the replicative DNA polymerase (Pol) III encounters a lesion, uncouples from DNA helicase, and single-stranded DNA (ssDNA) accumulates at the replication fork. In this study, we investigated DNA-peptide crosslink (DpC), a common lesion that results from cross-linking of proteins or peptides, UV irradiation, and alkylating agents. To increase survival following formation of a lesion, the SOS response can utilize homologous recombination, translesion synthesis (TLS), or excision repair. With TLS, the levels of DNA Pol II, IV, …

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 …

A Forward Genetic Screen To Identify Human Genes Of Interest And Their Roles In Ovarian Cancer, Susan A. Ihejirika

Honors College Theses

Drosophila melanogaster, fruit flies, are very important for modeling and studying human diseases. This study identifies human genes of interest and their contributions to epithelial ovarian carcinogenesis and progression as well as the roles orthologs of these genes play in Drosophila melanogaster. This is important because ovarian cancer is the most common cause of death among the gynecological cancers. This identification of genes was carried out using a forward genetic screen employing the widely used GMR-Gal4 driver/UAS-transgene system. The GMR-Gal4 driver is commonly utilized to express transgenes in the developing eye of the fruit fly. Transgenes that are expressed using …

Comprehensive Characterization Of The Genetic And Neoantigen Landscapes Of Follicular Lymphoma Patients Supports The Feasibility Of Personalized Cancer Vaccine Treatments, Cody Alexander Ramirez

Arts & Sciences Electronic Theses and Dissertations

Follicular lymphoma (FL) is the most common indolent non-Hodgkin’s lymphoma; however, it remains incurable with conventional therapies and is poorly responsive to checkpoint blockade. FL arises from B-lymphocytes and develops slowly (and often asymptomatically). A major research focus has been on how to avoid chemotherapy treatments, to limit the potential development of treatment-related side effects, and the risk of therapy-related second cancers. FL also carries an approximately 30% lifetime risk of transforming from an iNHL to more destructive lymphomas, which are associated with poorer prognosis. The most common transformation results in diffuse large B-cell lymphoma (DLBCL). However, many patients may …

Genetic Testing And A Real World Case Of Lynch Syndrome, Paige Montanaro

Senior Honors Projects

In recent years, advancements in genetic testing methods have revolutionized the medical field by enhancing the ability to identify persons with an inherited predisposition to cancer. According to the American Society for Clinical Oncology, individuals should undergo genetic testing when he or she meets the following criteria: the individual demonstrates familial history that indicates a predisposition to certain cancers, the test can be adequately interpreted, and the results will aid in the diagnosis, treatment, or management of the patient or additional family members at risk. Genetic testing can be done on samples of hair, skin, blood, amniotic fluid, or other …

Studies Of Norspermidine Uptake In Drosophila Suggest The Existence Of Multiple Polyamine Transport Pathways, Michael Dieffenbach

Honors Undergraduate Theses

Polyamines are a class of essential nutrients involved in many basic cellular processes such as gene expression, cell proliferation, and apoptosis. Without polyamines, cell growth is delayed or halted. Cancerous cells require an abundance of polyamines through a combination of synthesis and transport from the extracellular environment. An FDA-approved drug, D,L-α-difluoromethylornithine (DFMO), blocks polyamine synthesis but is ineffective at inhibiting cell growth due to polyamine transport. Thus, there is a need to develop drugs that inhibit polyamine transport to use in combination with DFMO. Surprisingly, little is known about the polyamine transport system in humans and other eukaryotes. Understanding the …

More Haste, Less Speed: Could Public-Private Partnerships Advance Cellular Immunotherapies?, Tania M. Bubela, Katherine Bonter, Silvy Lachance, Jean-Sébastien Delisle, E Richard Gol

Office of the Provost

Cellular immunotherapies promise to transform cancer care. However, they must overcome serious challenges, including: (1) the need to identify and characterize novel cancer antigens to expand the range of therapeutic targets; (2) the need to develop strategies to minimize serious adverse events, such as cytokine release syndrome and treatment-related toxicities; and (3) the need to develop efficient production/manufacturing processes to reduce costs. Here, we discuss whether these challenges might better be addressed through forms of public-private research collaborations, including public-private partnerships (PPPs), or whether these challenges are best addressed by way of standard market transactions. We reviewed 14 public-private relationships …

The Dlk1-Meg3 Locus In Malignant Cells Of Proposed Primordial Germ Cell Origins., Zachariah Payne Sellers

Electronic Theses and Dissertations

Primordial germ cells (PGCs) are hypothesized to deposit hematopoietic stem cells (HSCs) along their migration route through the embryo during the early stages of embryogenesis. PGCs also undergo global chromatin remodeling, including the erasure and reestablishment of genomic imprints, during this migration. While PGCs do not spontaneously form teratomas, their malignant development into germ cell tumors (GCTs) in vivo is often accompanied by the retention of hypomethylation at the IGF2-H19 imprinting control differentially methylated region (DMR). Previous studies in bimaternal embryos determined that proper genomic imprinting at two paternally imprinted loci was necessary for their growth and development: Igf2-H19 and …

Molecular Mechanisms Of Squamous Cell Carcinoma Tumor Stem Cell Creation Via High Nitric Oxide (Hno) Adaptation, Niresh T. Kuganeswaran '16, Krishi Korrapati '17, Thomas Wan '16, Timothy Tamas, James A. Radosevich

Student Publications & Research

Cancer relapse or recurrence is defined as the return of cancer or its signs/symptoms after a period of improvement. Surgery may not remove all cancer cells and leave behind a few which cannot be detected by scans or other tests. It is also possible that some tumor cells are resistant to chemotherapy or radiation. Although many cancer cells are killed by these treatments, there may exist a few which contain a different genetic makeup which allows them to survive. These hypermalignant cancer cells, or cancer stem cells (CSCs), have been associated with causing cancer relapse. It has also been predicted …

Role Of Pseudogenes In Cancer Stem Creation Via High Nitric Oxide (Hno) Adaptation, Krishi Korrapati '17, Niresh T. Kuganeswaran '16, Thomas Wan '16, Timothy Tamas, James A. Radosevich

Student Publications & Research

Gene chip analysis of ten HNO adapted cell lines (Squamous cells: SCC-016, SCC-040, SCC-056, SCC-114, SCC-116; Adenocarcinomas: A549, BT20, Hs578, MCF7, and T47D) was carried out. Known pseudogenes were identified in each line, as well as their coding counterparts.

The adenocarcinoma cell lines had no up regulated pseudogenes, while they had the following down regulated pseudogenes: RP6-159A1.2, RP11-255N24.3, AC004490.1, LDHBP, RP11-572H4.2. The squamous cell carcinomas (SCCs) had the following up regulated pseudogenes: RPL37AP1, AC138972.1, RP11-641D5.1, AC005534.6, AC022431.1, RPL26P12, and they had these down regulated pseudogenes: RP6-159A1.2, RP11-255N24.3, RBMXP1, RP11-20O23.1, RP11-551G24.2. All cell lines adhered to the hypothesis that an increase …

Modeling The Adaptive Immune Response To Mutation-Generated Antigens, Rory J. Geyer

University Scholar Projects

Somatic mutations may drive tumorigenesis or lead to new, immunogenic epitopes (neoantigens). The immune system is thought to represses neoplastic growths through the recognition of neoantigens presented only by tumor cells. To study mutations as well as the immune response to mutation-generated antigens, we have created a conditional knockin mouse line with a gene encoding, 5’ to 3’, yellow fluorescent protein (YFP), ovalbumin (which is processed to the immunologically recognizable peptide, SIINFEKL), and cyan fluorescent protein (CFP), or, YFP-ovalbumin-CFP. A frame shift mutation has been created at the 5’ end of the ovalbumin gene, hence YFP should always be expressed, …

Modeling The Adaptive Immune Response To Mutation-Generated Antigens, Rory J. Geyer

Honors Scholar Theses

Somatic mutations may drive tumorigenesis or lead to new, immunogenic epitopes (neoantigens). The immune system is thought to represses neoplastic growths through the recognition of neoantigens presented only by tumor cells. To study mutations as well as the immune response to mutation-generated antigens, we have created a conditional knockin mouse line with a gene encoding, 5’ to 3’, yellow fluorescent protein (YFP), ovalbumin (which is processed to the immunologically recognizable peptide, SIINFEKL), and cyan fluorescent protein (CFP), or, YFP-ovalbumin-CFP. A frame shift mutation has been created at the 5’ end of the ovalbumin gene, hence YFP should always be expressed, …

Genetics And Cancer, Sachin Puri

A with Honors Projects

Genes' effect in body and relationship with cancer. Role in cell cycle and angiogenesis.

Loss Of Bloom Syndrome Protein Causes Destabilization Of Genomic Architecture And Is Complemented By Ectopic Expression Of Escherichia Coli Recg In Human Cells, Michael Wayne Killen

University of Kentucky Doctoral Dissertations

Genomic instability driven by non-allelic homologous recombination (NAHR) provides a realistic mechanism that could account for the numerous chromosomal abnormalities that are hallmarks of cancer. We recently demonstrated that this type of instability could be assayed by analyzing the copy number variation of the human ribosomal RNA gene clusters (rDNA). Further, we found that gene cluster instability (GCI) was present in greater than 50% of the human cancer samples that were tested. Here, data is presented that confirms this phenomenon in the human GAGE gene cluster of those cancer patients. This adds credence to the hypothesis that NAHR could be …

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 …

Characterizing The Role Of Dna Repair Proteins In Telomere Length Regulation And Maintenance: Fanconi Anemia Complementation Group C Protein And 8-Oxoguanine Dna Glycosylase, David Beomjin Rhee

Doctoral Dissertations

Telomeres are the chromosome end structures consisting of telomere-associated proteins and short tandem repeat sequences, TTAGGG, in humans and mice. Telomeres prevent chromosome termini from being recognized as broken DNA ends. The structural integrity of DNA including telomeres is constantly threatened by a variety of DNA damaging agents on a daily basis. To counteract the constant threats from DNA damage, organisms have developed a number of DNA repair pathways to ensure that the integrity of genome remains intact. A number of DNA repair proteins localize to telomeres and contribute to telomere maintenance; however, it is still unclear as to what …