Cancer Biology Commons^™

Genetic Screen For Regulators Of Pol4, A Dna Repair Polymerase In Saccharomyces Cerevisiae, Pasang Dolma Sherpa

Theses and Dissertations

In Saccharomyces cerevisiae, DNA polymerase 4 (POL4) is the beta repair polymerase, the product of the POL4 gene, and is involved in base excision repair (BER) and microhomology-mediated end joining (MMEJ). Despite its involvement in these repair pathways and its conservation across eukaryotes, deletion of POL4 shows no detectable phenotype under standard laboratory conditions. I hypothesized that unknown genes act as backup systems, providing redundant activities that allow pol4Δ cells to survive. To test this, a genetic screen for mutants showing synthetic lethality with pol4Δ was implemented. I constructed a strain lacking the POL4 gene and carrying …

Global Erk/Mapk Activation Determines Oncogenic Fitness In Kras-Mutant Pancreatic Ductal Adenocarcinoma, Rachel A. Burge

MUSC Theses and Dissertations

In pancreatic ductal adenocarcinoma (PDAC), ~95% of cases harbor an activating KRAS mutation. The most common KRAS mutations in PDAC are KRAS^G12D (42%), KRAS^G12V (31%), and KRAS^G12R (15%). Patients harboring KRAS^G12R mutations have increased overall survival compared to those with KRAS^G12D/V-mutations. While KRAS^G12D/Vare common in all KRAS-mutant cancers, KRAS^G12Ris only common in PDAC.

KRAS^G12R is unable to activate the lipid kinase PIK3CA, a KRAS effector that is important for tumorigenesis in murine models. To investigate the tumorigenic potential of KRAS^G12R and the mechanisms that enable this mutation …

Investigating The Role Of The Lysine-Specific Demethylase 4c In Pancreatic Ductal Adenocarcinoma, Mennatallah Shaheen

Dissertations and Theses (Open Access)

Deregulation of proteins involved in chromatin regulation is common in pancreatic ductal adenocarcinoma (PDAC). Lysine demethylase 4C (KDM4C) is one of the chromatin modifying proteins frequently overexpressed across multiple solid cancers and is linked to chromatin instability, increased cell proliferation, and enhanced stem cell-like behavior. We observed upregulation of KDM4C protein in a panel of human PDAC cell lines and patient samples compared to non-neoplastic controls. CRISPR/Cas9-mediated deletion of KDM4C in human and murine PDAC cells reduced proliferation, clonogenicity, and increased survival of orthotopically implanted murine PDAC allografts. Transcriptomic and proteomics analyses revealed that loss of KDM4C in both human …

Identification Of Methylation Patterns, Associated Dna Methylating Proteins, And Methyltransferase Inhibitors On The Promoter Regions Of Dax-1, Brandon Tyler Toy

Master's Theses

The DAX-1 gene (Dosage-Sensitive Sex Reversal, Adrenal Hypoplasia Congenita, Critical Region on the X chromosome, gene 1) encodes for an orphan nuclear hormone receptor and its mutation is implicated in multiple diseases including congenital adrenal hypoplasia, adrenal cancer, and breast cancer. Previous research has linked DAX-1 downregulation to tumor initiation in breast tissue, suggesting the gene acts as a tumor suppressor with respect to breast cancer. Additional studies completed by the Tzagarakis-Foster laboratory have shown that methylation of the DAX-1 promoter region is heavily influential in breast cancer development, with release of epigenetic repression resulting in slowing of cellular proliferation …

Developing A Small Molecule To Inhibit Hsf1 Expression In Cancer And Evaluating Natural Genetic Variation In Small Molecule Toxicity., Michaela Kendal Foley

Theses and Dissertations

Each year cancer affects nearly 20 million people worldwide and genetic differences across populations can impact cancer onset and progression. Specifically, tumors with high levels of HSF1, the master regulator of the cytoprotective heat shock response (HSR), are correlated with poor patient outcomes in multiple cancers such as prostate, breast, and melanoma. Subsequently, the development of pharmacological inhibitors of HSF1 represents a promising strategy for anticancer therapeutics. Using a luciferase-based transcriptional reporter, two small molecule libraries were screened for inhibitors of HSF1 expression in human embryonic kidney cells, yielding ten compounds that decrease HSF1 expression. To identify if cancer lines …

Leveraging Attention Mechanism To Unlock Gene And Protein Attributes, Ala Jararweh

Computer Science ETDs

Advancing personalized medicine depends on effectively integrating and interpreting the vast, heterogeneous landscape of biological data, from genomic sequences and transcriptomics to the insights embedded in scientific literature. Current machine learning models often focus on single data modalities, limiting their capacity to capture the multifaceted nature of biological systems. We address this gap by developing three attention-based machine-learning models integrating diverse data modalities. Firstly, DeepVul is a multi-task model that leverages cancer transcriptome data to predict genes critical for cancer survival and their corresponding drugs. Subsequently, LitGene refines gene representations by integrating textual information from the scientific literature. Finally, Protein2Text …

Characterizing Kmt2d In Endometrial Cancer, Katherine R. Davanzo

Medical Student Research Symposium

Endometrial cancer is rising in incidence in the United States, notably among premenopausal women. This increase and the trend of delayed childbearing warrant the need for further advancement in fertility-sparing treatment for endometrial cancer. A gene left widely unexplored in its possible clinical utility as a target for fertility-sparing treatment is KMT2D, a lysine-specific methyltransferase and tumor suppressor. Preliminary gene set enrichment analysis on a 12Z endometriotic epithelial cell line identified TIMP3 as a gene that is possibly regulated by KMT2D expression. TIMP3 encodes an irreversible inhibitor of matrix metalloproteinases (MMPs), a well-recognized class of proteins as contributing to the …

The Role Of Secondary And Tertiary Structure In The Cap-Independent Translation Of Fgf-9 And Hif-1-Alpha, Amanda Michelle Whittaker

Dissertations, Theses, and Capstone Projects

Under normoxic conditions, eukaryotes initiate translation of RNA through eIF4E recognition of the 5’ cap. However, under cellular stress, eukaryotic translation must be initiated through a 4E-independent, or “cap-independent” mechanism, involving eukaryotic initiation factor 4G (eIF4G) binding directly to the 5’ untranslated regions (5’ UTR) of the RNA. eIF4G binding then recruits the ribosome to the transcript. While this mechanism is useful for translation of apoptotic transcripts and transcripts involved in cell survival, cap-independent translation is also utilized by oncogenic RNA for tumorigenesis. Previous work by our lab and others has categorized this recruitment and initiation mechanism as either internal-ribosome-entry-site …

The Effects Of Ewing Sarcoma Through The Overexpression And Knockdown Of Transcription Factors Sox18 And Stat1, Victoria Castillo, Melany Cervantes, Nicole Robles, Terry Jo Shackleford

Cell and Molecular Methods

SOX18, a transcription factor with a DNA-binding HMG domain, plays a critical role in regulatory processes linked to cancer progression. Exhibiting oncogenic properties, SOX18 has been linked to various cancers, where it promotes tumor growth by enhancing cell invasion, uncontrolled proliferation, and resistance to apoptosis through dysregulated signaling pathways. STAT1, a protein crucial for immune system regulation, is prominently expressed in immune-associated tissues like the lymph nodes, and bone marrow, suggesting it could play a role in tumor growth. Ewing Sarcoma (EWS), an aggressive cancer that targets bone and soft tissue, carries a high mortality rate of 90% without treatment …

Assessing The Temporal Role Of Mir-200 Loss In Murine Models Of Nsclc, Jared Fradette

Dissertations and Theses (Open Access)

Lung cancer is the leading cause of cancer related deaths in the United States, with non-small cell lung cancer (NSCLC) making up a majority of new diagnoses. Metastasis is the big killer in NSCLC and is driven by epithelial-mesenchymal transition (EMT) and immune evasion. The microRNA 200 family is a master regulator of EMT and is implicated in immune regulation. In this study we have developed a novel genetically engineered mouse model (GEMM) and derived primary cell lines from them to explore the role of microRNA-200 in early EMT and immune changes. Our model combines conditional activation of Kras^{G12D …}

Early Onset Alzheimer’S Disease Markers In Mouse Hippocampus Unveiled By Single-Cell Transcriptomic Analysis Following Cranial Radiotherapy, Tuba Aksoy

Dissertations and Theses (Open Access)

Cranial radiation therapy plays an integral role in the treatment of brain tumors but can lead to progressive cognitive deficits in survivors by mechanisms that are poorly understood. To develop preventive or mitigative strategies, it is crucial to better understand the underlying pathogenesis of radiation-induced cognitive impairments. The study investigated single-cell transcriptomics and DNA methylation changes as potential drivers of persistent cellular dysfunction after radiation exposure, specifically concentrating on the CA1-3 regions of the hippocampus and the prefrontal cortex due to their role in cognitive functions. Thirteen-week-old mice underwent whole-brain radiation at clinically relevant doses. Following whole-brain radiation, an assessment …

Unveiling The Nexus Of Cellular Quality Control: Exploring The Interplay Between Ribosome-Associated Protein Quality Control And Mitochondrial Quality Control Pathways, Foozhan Tahmasebinia

Biological Sciences Theses and Dissertations

In eukaryotic cells, the intricate interplay between cellular quality control mechanisms is crucial for maintaining homeostasis and safeguarding the integrity of vital processes, spanning from macromolecule synthesis to the renewal of entire cellular organelles.

Disruption of these networks can lead to severe diseases such as metabolic disorders, underscoring the interconnected nature and feedback control mechanisms inherent in biological systems, including cellular quality control systems. This interconnectedness extends to the intricate communication between organelles, enabling coordinated functioning and adaptation to changing cellular conditions, particularly in response to stressors.

While the exact mechanisms governing these communications within cellular quality control systems remain …

Identifying The Molecular Determinants Of Lung Metastatic Adaptation In Prostate Cancer, Grace M. Waldron

Theses & Dissertations

Prostate cancer (PC) stands as the primary diagnosed cancer in men in the US at approximately 299,010 cases in 2024 and ranks second globally, posing a significant public health challenge. Clinical presentations vary widely, from indolent to aggressive forms, necessitating stage-specific treatment regimens. Understanding its metastatic nature is critical due to the impact of cancer cell dissemination on disease morbidity, with bone and visceral organs serving as key sites of metastasis. Despite bone metastasis being the most common site for metastasis, visceral metastases at sites such as the liver and lungs correlate with poorer survival, emphasizing the role of microenvironmental …

Epigenetic Modification As A Therapeutic Target In Brafv600e-Mutated Metastatic Colorectal Cancer, Hey Min Lee

Dissertations and Theses (Open Access)

Patients with BRAF^V600E-mutated metastatic colorectal cancer (mCRC) experience a worse prognosis and demonstrate only a 5% response rate to BRAF inhibitor treatment. In this study, adaptive resistance, and a potential combination of standard therapies in BRAF^V600E CRC were unveiled. Intriguingly, a robust association of BRAF^V600E mutation and DNA hypermethylation suggests this is a unique subgroup harboring aberrant epigenetic phenotype. Firstly, DNA methyltransferase (DNMT) inhibitor treatment induced profound DNA hypomethylation in vivo, but minimal change in gene expression due to adaptive elevation of the repressive histone methylation, H3K27me3, leading to compensatory suppression of key tumor suppressor genes, …

The In4mer Crispr/Cas12a Multiplex Knockout Platform And Its Applications, Nazanin Esmaeili Anvar

Dissertations and Theses (Open Access)

Discovering synthetic lethal interactions between genes holds the key to uncovering cancer vulnerabilities, enabling the development of more effective drugs for patients. However, identifying these vulnerabilities in the complex genome of human, which comprises thousands of genes, poses a significant challenge. One alternative approach to investigate these interactions involves exploring enriched sources of synthetic lethal interactions, such as paralog pairs. In recent years, a couple of studies have conducted dual-gene knockout experiments on paralog pairs using different approaches to identify synthetic lethal interactions. In this study, we conducted a meta-analysis of CRISPR genetic interaction screens. We identified a candidate set …

Plk1 Overexpression Drives Tumorigenesis In A Prostate Cancer Mouse Model, Emile Kachouh

Theses and Dissertations

Prostate cancer is the leading cause of cancer-related deaths among men worldwide, and the development of resistance to existing treatments necessitates the exploration of new therapeutic strategies, including combination therapies. This study investigates the role of Polo-like kinase 1 (PLK1), located on chromosome 16p12.2, as an oncogene in prostate cancer. We generated a transgenic mouse model with prostate-specific overexpression of PLK1 to closely mimic human prostate cancer progression. Quantitative PCR (qPCR) analysis was employed to characterize the molecular profile of PLK1, revealing its implication in multiple pathways. To further elucidate the functional consequences of PLK1 overexpression, we confirmed phenotypic progression …

Delineating Contributions Of Genotype And Lineage To Lung Cancer Therapy Response, Kassandra Jo Naughton

Theses and Dissertations--Toxicology and Cancer Biology

Non-small cell lung cancer (NSCLC) heterogeneity is a major challenge for determining effective treatment strategies. Adenocarcinomas (ADCs) and squamous cell carcinomas (SCCs) are histologically and epigenetically distinct subtypes of NSCLC. Patients with ADC tumors harboring mutations in both KRAS and LKB1 (aka STK11) have lower survival rates than those with KRAS-only tumors. KRAS/LKB1 tumors are not only aggressive, but also respond poorly to immunotherapy. However, these data are limited to ADCs, and it is unclear if SCCs with this genotype are also resistant to immunotherapy. We developed a mouse model of Kras^mut/Lkb1^mut capable of producing …

Exploring 3d Genome Interaction And Epigenetic Regulation Via Swi/Snf Complex And Deep Learning Models, Ruoyun Wang

Dartmouth College Ph.D Dissertations

The three-dimensional organization of the genome is fundamental in regulating gene expression and maintaining cellular function. This organization's complexities, influenced by epigenetic marks and chromatin remodeling complexes, are crucial for understanding genomic regulation. Among these, the SWI/SNF complexes are key, facilitating chromatin accessibility and regulating gene activity across cell types. The first part of my dissertation focuses on SWI/SNF complexes, exploring their role in chromatin remodeling and their impact on 3D genome architecture. Utilizing next-generation sequencing (NGS) techniques, this section investigates the interplay between these complexes and chromatin structure. During my research on the SWI/SNF complex, I was intrigued by …

Genomic Characterization Of Adolescent And Young Adult Cancers: Investigation Of Ewing Sarcoma Susceptibility And Chornobyl Thyroid Tumors, Olivia Lee

Dissertations and Theses (Open Access)

Adolescent and young adult (AYA) cancers, diagnosed between the ages of 15 and 39, can exhibit distinctive genetic and molecular characteristics. Reported epidemiologic findings and treatment outcomes based on pediatric and adult cancer studies are often not suitable for application to the AYA population, underscoring the need for more thorough genomic research. Advances in sequencing technologies have enabled comprehensive analyses of complex genomic characteristics of AYA cancers, crucial for understanding the underlying biology of these malignancies. Here, I have utilized advanced sequencing techniques and integrated analytic approaches to describe important genomic features in two different AYA cancer types: Ewing Sarcoma …

The Use Of Prognostic Markers To Predict Disease Progression And Clinical Outcome In Monoclonal Gammopathy Of Undetermined Significance, Smouldering Multiple Myeloma And Multiple Myeloma., Róisín C. Mcmonagle

International Undergraduate Journal of Health Sciences

Multiple Myeloma (MM) is an incurable plasma cell malignancy with a complex and incompletely understood molecular pathogenesis. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smouldering Multiple Myeloma (SMM) precede MM, with variable risks and rates of disease progression. The continuing high relapse and death rate in MM cases has prompted research into more accurate prognostic markers to predict progression from MGUS and SMM to MM, as well as identify MM cases with aggressive disease, in order to begin early, targeted and effective therapeutic intervention. Many studies have focused on utilising current markers more effectively, including M-protein, serum-free light chain ratio, …

Regulation Of The Wnt/Wingless Receptor Lrp6/Arrow By The Deubiquitylating Complex Usp46, Zachary T. Spencer

Dartmouth College Ph.D Dissertations

The evolutionarily conserved Wnt/Wingless signal transduction pathway is critical for the proper development of all animals and implicated in numerous diseases in adulthood. Upon binding of the Wnt/Wingless ligand, a cascade of events culminates in inactivation of the destruction complex, a negative regulator of the pathway, and the subsequent formation of singalosomes which mediate pathway activation. A critical component of signalosome formation is the Wnt/Wingless receptor LRP6/Arrow. Upon canonical pathway activation, LRP6/Arrow undergoes activation via phosphorylation by several kinases and complexes with another Wnt/Wingless receptor Frizzled, along with several cytoplasmic components. While many studies have investigated the regulatory mechanisms of …

Zinc Treatment Reverses And Anti-Zn-Regulated Mirs Suppress Esophageal Carcinomas In Vivo, Louise Fong, Kay Huebner, Ruiyan Jing, Karl Smalley, Christopher R Brydges, Oliver Fiehn, John Farber, Carlo M Croce

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Esophageal squamous cell carcinoma (ESCC) is a deadly disease with few prevention or treatment options. ESCC development in humans and rodents is associated with Zn deficiency (ZD), inflammation, and overexpression of oncogenic microRNAs: miR-31 and miR-21. In a ZD-promoted ESCC rat model with upregulation of these miRs, systemic antimiR-31 suppresses the miR-31-EGLN3/STK40-NF-κB-controlled inflammatory pathway and ESCC. In this model, systemic delivery of Zn-regulated antimiR-31, followed by antimiR-21, restored expression of tumor-suppressor proteins targeted by these specific miRs: STK40/EGLN3 (miR-31), PDCD4 (miR-21), suppressing inflammation, promoting apoptosis, and inhibiting ESCC development. Moreover, ESCC-bearing Zn-deficient (ZD) rats receiving Zn medication showed a 47% …

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, …

P53 Dimers Elicit Unique Tumor Suppressive Activities Through An Altered Metabolic Program, Jovanka Gencel-Augusto

Dissertations and Theses (Open Access)

p53 is the most frequently mutated tumor suppressor in human cancer. As a tetrameric transcription factor, mutation of the p53 Tetramerization Domain (TD) is a mechanism by which cancers abrogate wild-type (WT) p53 function. p53 TD mutations result in a protein that preferentially forms monomers or dimers. These are also normal p53 states under basal cellular conditions. Although it is accepted that tetrameric p53 is required for full tumor suppressive activities, the physiological relevance of monomeric and dimeric states of p53 is not well understood. We have established in vivo models for monomeric and dimeric p53 which model Li-Fraumeni Syndrome …

Functional Analysis Provides Insight Into Missing Heritability, Scott L. Baughan, Michael A. Tainsky, Fatima Darwiche

Medical Student Research Symposium

Accurate ascertainment of genetic risk can be potentially lifesaving for patients who inherit cancer promoting mutations. However, even with the most extensive panel testing clinically available, a large number of patients will test negative despite family history of cancer or test positive for a variant of unknown significance (VUS). For these patients, clinical management is complicated; patients want to know their risk, and may fear disease they are not at great risk for (benign VUS) or they may not be given access to potentially lifesaving early screening procedures (pathogenic VUS). ATM has proven a challenge to clinicians due to its …

Revolutionary Advances In The Treatment Of Genetic Disease, Emma Kaitlyn Carrigan

Honors Theses and Capstones

No abstract provided.

Cell Signaling And Stress Response In The Yeast Saccharomyces Cerevisiae: A Study Of Snf1, Scott E. Arbet Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Saccharomyces cerevisiae are yeast that are unicellular eukaryotic organisms that are well studied as a model organism for understanding fundamental cellular processes. The ability of yeast to sense nutrient availability is crucial for their survival, growth, and reproduction. Yeast cells use various mechanisms to sense and respond to nutrient availability, including transporter-mediated uptake, receptor-mediated signaling, and sensing of metabolites. The subcellular localization of nutrient-sensing components is crucial for yeast function in nutrient sensing and signaling. Protein complexes, such as the AMP-activated protein kinase (AMPK) pathway, in nutrient sensing and response, as well as the downstream effects of these pathways …

The Genetics Of Skin Cancer: What Genes Drive The Development Of Basal Cell Carcinoma, Squamous Cell Carcinoma, And Melanoma?, Cassandra Poole, Abagail Pack, Elizabeth Whitehead, Virginia Marshall

Fall Showcase for Research and Creative Inquiry

Skin cancer is one of the most common forms of cancer worldwide. The American Academy of Dermatology estimates that 9500 people in the United States are diagnosed with skin cancer every day, and that 1 in 5 Americans will be diagnosed with skin cancer by age 70. With such a high prevalence of disease, understanding how skin cancer develops and how it can be treated is extremely important. This project aims to analyze the genes involved in the development of the three most common forms of skin cancer: basal cell carcinoma, squamous cell carcinoma, and melanoma.

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …

Utilizing Pharmacology To Target Transcription Factors Involved With Cancer Onset And Development, Tristan D. Sanders

Mountaineer Undergraduate Research Review

Transcription factors (TFs) are a vital part of every living organism on earth, as they allow for the correct genes to be expressed while much of the genome is never used. They can fall victim to mutations or manipulations that lead to the deregulation of many genes within a cell. If specific genes are over/under-expressed, a cell may become cancerous and begin replicating into a tumor. It has been demonstrated that common TFs associated with cancer can be targeted using small molecule drugs, and a popular target of these drugs is the DNA binding site on the TF along with …