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Uncovering A Myc-Driven Tumor-Suppressive Program In Proliferating Lymphocytes, Elena Tonc

Arts & Sciences Electronic Theses and Dissertations

Rapid cell proliferation is a hallmark feature of adaptive immune cells lymphocytes. It is essential for the establishment of diverse antigen receptor repertoires and amplification of antigen-specific immune responses. While such proliferation is beneficial for host protection from infections and cancers, it inevitably elevates the risk of oncogenic transformation. In developing and germinal center B lymphocytes, the risk is further increased by endogenous, genomic insults due to antigen receptor rearrangements and somatic mutations, with which expression of the proto-oncogene c-MYC is closely associated. Nonetheless, frequencies of cancers originated from B lymphocytes are relatively low, suggesting that they are protected from …

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 …

Mechanisms Of Cross-Presentation By Cdc1s, Derek James Theisen

Arts & Sciences Electronic Theses and Dissertations

Classical dendritic cells (cDCs) are specialized antigen presenting cells that can be divided into distinct subsets based on the types of pathogens they respond to and the type of immune response they generate. The cDC1 subset is specialized in priming CD8 T cell responses through the process of cross-presentation. During cross-presentation, exogenous protein antigens are taken up by cDC1 and presented on MHCI molecules, allowing for the priming of CD8 T cells during conditions when DCs themselves are not directly infected. The ability to cross-present in vivo is unique to cDC1, and is essential for anti-viral responses and rejection of …

Multi-Omics Integration For Gene Fusion Discovery And Somatic Mutation Haplotyping In Cancer, Steven Mason Foltz

Arts & Sciences Electronic Theses and Dissertations

Cancer is a disease caused by changes to the genome and dysregulation of gene expression. Among many types of mutations, including point mutations, small insertions and deletions, large scale structural variants, and copy number changes, gene fusions are another category of genomic and transcriptomic alteration that can lead to cancer and which can serve as therapeutic targets. We studied gene fusion events using data from The Cancer Genome Atlas, including over 9,000 patients from 33 cancer types, finding patterns of gene fusion events and dysregulation of gene expression within and across cancer types. With data from the CoMMpass study (Multiple …

Mechanosensitive Epithelial Cell Scattering And Migration On Layered Matrices, Christopher Michael Walter

McKelvey School of Engineering Theses & Dissertations

Epithelial cells form multi-layered tissue scaffolding that makes up every organ in the body. Along with epithelial cells, the basement membrane (BM) and connective tissue are composed of various proteins that sculpt the organs and protect them from foreign macromolecules. Epithelial cells respond to various cues, both chemical and mechanical, from their surrounding matrices to aid in maintenance and repair of these layers through degradation and deposition of extracellular matrix (ECM) proteins. In cancer progression, epithelial cells lose their normal function of supporting tissue structure and instead adopt more aggressive behaviors through an epithelial-to-mesenchymal transition (EMT) of their cellular traits. …

The Role Of Ifrd1 In The Recruitment And Function Of Reserve Stem Cells In Regeneration And Cancer, Mark Anthony Lewis

Arts & Sciences Electronic Theses and Dissertations

Mature cells can reprogram into a proliferative, progenitor-like state to repair tissue following injury and inflammation. Differentiated cells in diverse tissues can become proliferative via a dedicated, evolutionarily conserved program we termed paligenosis. We detailed how paligenosis occurs, in both gastric chief and pancreatic acinar cells, in a step-wise manner that involves: 1) autodegradation of mature cell components; 2) re-expression of progenitor genes; 3) re-entry into the cell cycle. This process is governed by mTORC1, a fundamental cellular energy sensor and regulator of protein translation. Blocking mTORC1 permitted autophagy and metaplastic gene induction but blocked cell cycle re-entry at S-phase. …

Development Of Novel Tumor-Targeted Compounds For Boron Neutron Capture Therapy, Micah John Luderer

Arts & Sciences Electronic Theses and Dissertations

Glioblastoma multiforme (GBM) represents the most common primary brain tumor among adults. Despite surgical resection and aggressive chemoradiotherapy regimens, the current 2- and 5-year survival rates are only 27% and 9.8%, respectively. The low survival stems from the poor response to conventional therapy and underscores the critical need to develop new therapeutic approaches for GBM treatment. The high recurrence rate observed in GBM is in part attributed to the hypoxic (poorly oxygenated) tumor microenvironment. Hypoxic tumor conditions have been shown to increase metastasis, promote angiogenesis, and confer resistance to chemotherapy and radiation.

Hypoxic tissues are inherently radiation resistant due to …

The Splice Is Not Right: Splice-Site-Creating Mutations In Cancer Genomes, Reyka Glencora Jayasinghe

Arts & Sciences Electronic Theses and Dissertations

Accurate interpretation of cancer mutations in individual tumors is a prerequisite for precision medicine. Large-scale sequencing studies, such as The Cancer Genome Atlas (TCGA) project, have worked to address the functional consequences of genomic mutations, with the larger goal of determining the underlying mechanisms of cancer initiation and progression. Many studies have focused on characterizing non-synonymous somatic mutations that alter amino acid sequence, as well as splice disrupting mutations at splice donors and acceptors. Current annotation methods typically classify mutations as disruptors of splicing if they fall on the consensus intronic dinucleotide splice donor, GT, the splice acceptor, AG. Splice …

Multi-Omics Portraits Of Cancer, Kuan-Lin Huang

Arts & Sciences Electronic Theses and Dissertations

Precision oncology demands accurate portrayal of a disease at all molecular levels. However, current large-scale studies of omics are often isolated by data types. I have been developing computational tools to conduct integrative analyses of omics data, identifying unique molecular etiology in each tumor. Particularly, this dissertation presents the following contributions to the computational omics of cancer: (1) uncovering the predisposition landscape in 33 cancers and how germline genome collaborates with somatic alterations in oncogenesis; (2) pioneering methods to combine genomic and proteomic data to identify treatment opportunities; and (3) revealing selective phosphorylation of kinase-substrate pairs. These findings advance our …

Tumors Interrupt Irf8-Mediated Dendritic Cell Development To Overcome Immune Surveillance, Melissa Ann Meyer

Arts & Sciences Electronic Theses and Dissertations

Tumors employ multiple mechanisms to evade immune surveillance. One mechanism is tumor-induced myelopoiesis, which expands immune suppressive granulocytes and monocytes to create a protective tumor niche shielding even antigenic tumors. As myeloid cells and immune-stimulatory conventional dendritic cells (cDCs) are derived from the same progenitors, it is logical that tumor-induced myelopoiesis might also impact cDC development. The cDC subset cDC1 is marked by CD141 in humans and CD103 or CD8α in mice. cDC1s act by cross presenting antigen and activating CD8+ T cells. Given these functions, CD103+ cDC1s can support anti-tumor CD8+ T cell responses. However, CD103+ cDC1 numbers are …

Designing Epigenome Editing Tools To Understand The Functional Role Of Dna Methylation Changes In Cancer, James Mcdonald

Arts & Sciences Electronic Theses and Dissertations

DNA methylation is known to silence gene expression in the context of imprinting, X-chromosome inactivation, and retrotransposon silencing. However, the role of DNA methylation in silencing gene expression outside of these contexts is not fully understood. This is especially true in diseases such as cancer, where normal DNA methylation patterns are significantly altered. In breast cancer as well as nearly all cancer types, most of the genome loses DNA methylation while small regions of the genome gain methylation. DNA methylation generally correlates with decreased gene expression when present at a gene promoter. Therefore, these regions of hypo- and hyper-methylation may …

Mechanisms And Regulation Of Resection In Dna Damage Response, Sharad C. Paudyal

Arts & Sciences Electronic Theses and Dissertations

Deoxyribonucleic acid (DNA) encodes genetic information essential for cell survival and function. However, it is constantly under assault from endogenous and exogenous damaging agents that not only threaten our own survival but also affect the faithful transmission of genetic information to our offspring. Double-strand breaks (DSBs) are one of the most hazardous forms of DNA damage, which if unrepaired or improperly repaired could lead to plethora of systemic human diseases including cancer. To deal with this problem, cells have evolved with a mechanism called DNA damage response (DDR) to detect, signal, and repair the breaks by inducing multiple cellular events. …

Dna Replication Challenges: Telomeres And R Loops, Shankar Parajuli

Arts & Sciences Electronic Theses and Dissertations

Faithful DNA replication and repair are essential for maintaining genome stability and preventing various diseases including cancer. Both processes are executed by numerous redundant mechanisms to ensure that these processes are uninterrupted even when a primary mechanism fails. Despite this, they are not immune to challenges and failures leading to DNA damage and genome instability. These problems are more evident at the difficult-to-replicate regions of the genome such as the telomeres that cap and protect linear chromosome ends. Additionally, topological structures such as RNA:DNA hybrids, commonly referred to as R loops, can also present severe challenges to the DNA replication …

Mitochondrial Dynamics Controls T Cell Fate Through Metabolic Programming, Michael Buck

Arts & Sciences Electronic Theses and Dissertations

Activated effector T (TE) cells augment anabolic pathways of metabolism, such as aerobic glycolysis, while memory T (TM) cells engage catabolic pathways, like fatty acid oxidation (FAO). However, signals that drive these differences remain unclear. Mitochondria are metabolic organelles that actively transform their ultrastructure. Therefore, we questioned whether mitochondrial dynamics controls T cell metabolism. We show that TE cells have punctate mitochondria, while TM cells maintain fused networks. The fusion protein Opa1 is required for TM, but not TE cells after infection, and enforcing fusion in TE cells imposes TM cell characteristics and enhances antitumor function. Our data suggest that, …

The Role Of Dnmt3a In Acute Myeloid Leukemia Pathogenesis, Christopher Browning Cole

Arts & Sciences Electronic Theses and Dissertations

Loss of function mutations in the DNA methyltransferase DNMT3A are highly recurrent in acute myeloid leukemia (AML). DNMT3A and the highly homologous gene DNMT3B encode the two methyltransferases that are primarily responsible for mediating de novo methylation of specific DNA sequences during cellular differentiation. DNMT3A mutations are mutually exclusive of several translocations that create oncogenic fusion genes (PML-RARA, RUNX1-RUNX1T1, CBFB-MYH11, and MLL-X), suggesting that these fusions may require functional DNMT3A to initiate leukemogenesis. Using bone marrow cells from a constitutive Dnmt3a null mouse, we show that loss of Dnmt3a caused a striking loss of DNA methylation throughout the genome of …