Cancer Biology Commons^™

Oxidative Stress Mediated Glutamate Release And Nmda Receptor-Dependent Synaptic Remodeling In Radiation-Induced Cognitive Dysfunction, Thanh Lam

Dissertations and Theses (Open Access)

In children younger than 14 years old, the brain and other parts of the central nervous system are the most common sites for solid tumors. Radiotherapy is an effective treatment for central nervous system (CNS) tumors. However, it often causes a progressive decline in cognitive functions, which is especially devastating for pediatric patients. Although post-mitotic neurons are generally considered resistant to radiation-induced immediate cell death, ionizing radiation causes complex neurochemical and structural changes that damage synaptic integrity. In this study, we examined the molecular cascades following a 10 Gy radiation dose applied to mouse cortical neurons. We found that radiation-induced …

Effects Of M6a Dna Methylation By Bacterial Methyltransferase In Colorectal Cancer, Fabian Alejandro Mendoza Galvan

Dissertations and Theses (Open Access)

Effects of m6A DNA methylation by bacterial methyltransferase in colorectal cancer Fabian Alejandro Mendoza Galvan Advisory Professor: Angela H. Ting, Ph.D. Fusobacterium nucleatum animalis (Fna) is found in the human oral cavity and gut. A distinct clade of Fna is primarily enriched in the tumor microenvironment (TME) and within colorectal cancer (CRC) cells. This clade DNA methylation pattern is primarily catalyzed by a cell-cycle regulated methyltransferase (CcrM) ortholog, M.FnI, that targets the GANTC sequence motif through methyl-6-Adenine (m6A) DNA methylation. We hypothesized that M.FnI enzyme can induce m6A methylation abnormalities in CRC cells to promote cancer progression. Evidence for endogenous …

Targeting Breast Cancer Brain Metastasis Through Novel Combination Of Fda-Approved Orally Active Blood-Brain Barrier Permeable Ret And Tgli1 Inhibitors, Joshua Cha

Dissertations and Theses (Open Access)

Breast cancer is the most diagnosed cancer in American women, and breast cancer brain metastasis (BCBM) exhibits the worst prognoses with a life-expectancy averaging at 6 months. This short life expectancy is largely attributed to the lack of effective treatment. Many challenges remain unsolved, including the limited number of actionable targets for targeted therapy and effective blood-brain barrier (BBB) permeable drugs that are safe without promoting drug resistance. Therefore, there is an urgent call for identification of novel therapeutic targets and development of BBB-permeable drugs. One of the potential targets identified by our lab for BCBM targeted therapy is the …

From Antigen Presentation To Tumor Control: Mechanisms Of Type I Conventional Dendritic Cell-Based Cancer Vaccines, Josue E. Pineda

Dissertations and Theses (Open Access)

Type 1 conventional dendritic cells (cDC1s) are important for generating and sustaining antitumor immunity. Accordingly, the abundance of cDC1s in human tumors correlates with improved outcomes in cancer. Capitalizing on this role, we previously demonstrated that vaccination with in vitro-derived murine cDC1s elicits durable tumor control in multiple preclinical models; however, the immunological mechanisms underlying the efficacy of cDC1 vaccination remain unclear. Here, we examined whether in vitro-derived cDC1s resemble tumor-infiltrating DC populations and whether MHC-I and MHC-II antigen presentation contribute to cDC1-mediated tumor control following vaccination in melanoma.

As expected, MHC-I- or MHC-II-deficiency had minimal impact on …

Understanding Epigenomic Landscapes In Cancer Progression And Immunotherapy Response, Jonathan Schulz

Dissertations and Theses (Open Access)

Nonmutational epigenomic reprogramming has emerged as a key hallmark of cancer that plays crucial roles in tumor evolution during its progression and response to therapy. However, the extent and nature of epigenomic reprogramming remains poorly understood. This dissertation examines how epigenetic regulation shapes cancer progression and response to immunotherapy. Working at the intersection of cancer biology and computational genomics, it develops analytical frameworks for characterizing chromatin structure and DNA methylation across diverse tumor contexts and uses these frameworks to address two complementary biological questions: how promoter-associated chromatin organization varies across cancer types, and how epigenetic perturbation modulates tumor immunogenicity in …

Host-Intrinsic Factors Determine Anti-Tumor Efficacy Of Exercise In Pancreatic Ductal Adenocarcinoma, Sumedha Pareek

Dissertations and Theses (Open Access)

Pancreatic Ductal Adenocarcinoma (PDAC) is the third leading cause of cancer-related deaths with a low 5-year relative survival rate of approximately 13.3% for all stages combined. We have previously shown that exercise can improve quality of life and enhance functional capacity among patients with PDAC. Exercise induces a variety of changes in the tumor microenvironment with beneficial effects in several tumor types. However, our understanding of the clinical effects of exercise and the mechanisms that mediate anti-tumor effects are limited in pancreatic cancer.

In this project, using C57BL/6 mice from Taconic Biosciences (Tac) and Jackson Laboratories (Jax), we established a …

Integrating Bulk And Single-Cell Transcriptomics To Investigate Intratumor Heterogeneity, Shuai Guo

Dissertations and Theses (Open Access)

Cancers are heterogeneous mixtures of tumor and surrounding cells, where each component comprises multiple distinct sub-types and/or states. Understanding the cell-type-specific contributions is critical for advancing cancer biology, yet high-throughput expression profiles from tumor tissues only represent combined signals from all diverse cellular sources. Bulk deconvolution with single-cell/nucleus (sc/sn) RNA-seq data has emerged as a powerful approach to dissect both cellular composition and cell-type-specific expression patterns, yet the technological discrepancy across sequencing platforms limits accuracy.

To systematically evaluate the impact of platform discrepancies on bulk deconvolution, we first generated a benchmark dataset of 24 healthy retinas with paired bulk and …

Clonal Phenotype Mapping Reveals Genomic Alterations Underlying Tumor Immunosuppression During Immunotherapy, Er-Yen Yen

Dissertations and Theses (Open Access)

Tumors are dynamic ecosystems that evolve under selective pressures, shaping their ability to either elicit or evade immune responses. In pancreatic ductal adenocarcinoma (PDAC), where immunotherapy has yet to become an effective treatment option, we investigated the role of intratumoral heterogeneity in influencing immune interactions. Using orthotopic clonal replica tumors, we tracked clonal dynamics in response to anti-PD1 therapy and found that while treatment had limited impact on overall tumor volume, it induced profound shifts in clonal composition. Spatial lineage analysis of treatment-naïve tumors revealed that clones with distinct immunotherapy sensitivities occupy unique tumor microenvironments, a pattern that remained stable …

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 …

Fc Gamma Receptors Facilitate Antigenic Modulation Of Lilrb4 And Function As Predictive Biomarkers In Acute Monocytic Leukemia, Joshua Morse

Dissertations and Theses (Open Access)

Acute monocytic leukemia (monocytic AML) is a subtype of AML marked by a proliferation of abnormal monoblasts. This subtype represents approximately 10% of AML cases. The prognosis of monocytic AML is poor, with a 5-year survival of ~30%. Most patients are diagnosed at an age when they are unlikely to survive first-line non-targeted cytotoxic chemotherapy as a bridge to hematopoietic stem cell transplant (HSCT). Even patients who achieve remission commonly relapse. This population of patients would greatly benefit from precision-targeted therapies but currently there are none approved for monocytic AML.

Leukocyte immunoglobulin-like receptor B4 (LILRB4) is an immune checkpoint expressed …

The Role Of Ucp2 In Pancreatic Cancer Metabolism And Its Potential As A Radiosensitizer, Emily Rieff

Dissertations and Theses (Open Access)

Uncoupling protein 2 (UCP2) is a mitochondrial protein that regulates the flow of protons down the gradient established by the electron transport chain (ETC) without generating ATP, thus uncoupling the proton gradient from ATP generation. In tumors, specifically pancreatic cancer (PDAC), the ETC is highly stimulated to generate the copious ATP needed by the tumor to grow. However, extended ETC use increases reactive oxygen species (ROS), and if left unchecked, results in cell death. To evade this, PDAC employs antioxidant strategies, including upregulating UCP2 in tumor cells. In addition to its uncoupling function, UCP2 indirectly controls ROS levels by maintaining …

Therapeutic Vulnerabilities Of Venetoclax Resistant Chronic Lymphocytic Leukemia And Novel Treatment Strategies Targeting Bcl2/Bcl-Xl, Daisy Y. Diaz-Rohena

Dissertations and Theses (Open Access)

Despite major advancements in the management of chronic lymphocytic leukemia (CLL), drug resistance remains a major challenge. CLL resistant to venetoclax (VEN) have limited available therapeutic options, especially when the leukemic cells have dysfunctional p53 and have relapsed on Bruton’s tyrosine kinase inhibitors (BTKi). The broad hypothesis of this thesis is that VEN-relapsed CLL exhibits altered dependence on BCL2 family members, which can be exploited for therapeutic benefit. I profiled 28 CLL samples collected from 15 patients either at baseline or at relapse following VEN treatment, which was administered in combination with a BTKi or sequentially as monotherapy after a …

Ascl2 Positive Tumor Cells Modulate The Response Of Metastatic Colorectal Cancer To Mapk-Targeting Therapy, Oscar Eduardo Villarreal

Dissertations and Theses (Open Access)

Colorectal cancer (CRC) is the second leading cause of cancer related deaths with nearly a quarter of patients presenting with metastatic disease at the time of their diagnosis. Therapeutic management of metastatic CRC continues to be a major challenge due to therapy resistance and disease heterogeneity. Due to its central role in tumorigenesis, CRC is commonly treated with MAPK pathway inhibitors (MAPKi). However, clinical trials repeatedly demonstrates that durability of benefit is short-lived in many patients. While genomic mechanisms of acquired resistance have been described, they explain a minority of patients, and further research is needed to determine the underlying …

Identification Of Mitochondrial Defects And Metabolic Consequences In Lynch Syndrome-Related Endometrial Cancer, Mikayla Bowen

Dissertations and Theses (Open Access)

Lynch syndrome (LS), defined by mutations in DNA mismatch repair genes including MSH2, carries a 60% lifetime risk of developing endometrial cancer (EC). Mismatch repair deficiency (MMRd) causes hypermutability, which is assumed to be the main driver of LS-related EC development. However, incomplete penetrance of EC development in women with LS suggests that other modulators are at play. The broad hypothesis of this dissertation is that MMRd causes consequences beyond hypermutability to impact LS-related EC development. Recent studies utilizing our lab’s Msh2-deficient mouse model for LS-EC revealed mitochondrial dysfunction in EC pathogenesis. This new insight led to the …

Developing Novel Therapies Targeting The Tumor Microenvironment Of Aggressive Breast Cancer, Lan T H Phi

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) and inflammatory breast cancer (IBC) are the most aggressive breast cancer subtypes. The tumor microenvironment (TME) is critical in driving these aggressive breast cancers' clinical phenotype and aggressiveness. Therefore, we explored novel actionable targets and complementary therapies targeting the TME to improve the outcomes of patients with these cancers.

In this thesis, we identified AXL as a potential therapeutic target in IBC due to its role in generating an immunosuppressive TME. Indeed, inhibiting the AXL pathway suppresses IBC tumor growth and reduces M2 macrophage populations in various mouse models. Mechanistically, AXL facilitates the polarization of M2 …

Impact Of Tumor Cell Expressed Cd38 On Metastasis And Immune Evasion In Breast Cancer, Tanvi Visal

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) is a highly metastatic breast cancer subtype. The epithelial-to-mesenchymal transition (EMT) of cancer cells is a key feature of the metastatic cascade and is not a binary process but often generates malignant cells with both epithelial (E) and mesenchymal (M) traits known as hybrid EM cells. Recent studies highlight the enhanced metastatic potential of the hybrid EM cells. However, molecular insights and targetable vulnerabilities within hybrid EM remain elusive. We discovered that hybrid EM murine tumors are enriched in CD38, an immunesuppressive molecule associated with worse clinical outcomes in liquid malignancies but relatively understudied in solid …

Relationship Between Processing Body Formation, Epithelial-To-Mesenchymal Transition, And Invasion In Lung Adenocarcinoma, Amanda Warner

Dissertations and Theses (Open Access)

Lung cancer is the leading cause of cancer-related deaths in the United States, largely due to its ability to metastasize. Epithelial-to-mesenchymal transition (EMT) is a process that enhances the ability of cells to lose their cell-cell contacts, invade, and enter the blood stream which are essential during metastasis. Many transcriptional gene programs are altered during EMT such as activation of mesenchymal transcription factors, like ZEB1, and enhanced response to the TGFβ1 cytokine. In oncogenic contexts, TGFβ1 enhances the formation of processing-bodies (P-bodies) where P-body proteins are required for invasion in multiple cancerous cell lines. P-bodies are a type of ribonucleoprotein …

Overcoming Resistance To Cdk4/6-Targeted Therapy Using Jak2/Stat3 Inhibitor In Triple-Negative Breast Cancer, Chuling Zhuang

Dissertations and Theses (Open Access)

Breast cancer is the most common type of cancer diagnosed in women, with nearly 30% of cases becoming metastatic accounting for over 90% of breast cancer-related deaths. Among different breast cancer subtypes, triple-negative breast cancer (TNBC) has the worst prognosis and the highest propensity to metastasize. However, TNBC patients have limited treatment options due to their lack of actionable drug targets while therapeutic resistances result in high rates of recurrence and metastasis. Cyclin-dependent kinase 4 and 6 (CDK4/6) are major cell cycle regulators that control G1 to S phase transition and aberrant hyperactivation of the CDK4/6 pathway results in uncontrolled …

Harnessing The Immunomodulatory Potential Of Radiofrequency Ablation To Improve Therapeutic Outcomes In Pancreatic Ductal Adenocarcinoma, Bhumi Maniyar

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) continues to rank among the most lethal cancers with poor prognosis. PDAC is characterized by a thick desmoplastic stroma, severe immunological suppression, and resistance tostandard treatments. The need for innovative therapeutic approaches is highlighted by the tumor microenvironment's (TME) critical role in promoting disease development and reducing the effectiveness oftreatment. A promising locoregional treatment that can induce tumor necrosis and modify the TME is endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA). However, there is still minimal understanding around its wider impact on stromal remodeling and immunological activation. This study investigates the immunomodulatory effects of RFA combined with neoadjuvant …

Role Of Mir-4732-3p In Breast Cancer Brain Metastasis And Brain Metastatic Tumor Microenvironment, Munazza Samar Khan

Dissertations and Theses (Open Access)

In this study, we aimed to identify microRNAs (miRNAs) that may play important roles in breast cancer brain metastasis (BCBM). To this end, we conducted miRNA-sequencing of extracellular vesicles isolated from the serum samples of 6 BCBM patients and 8 Stage I/II/III breast cancer patients, and identified 49 circulating miRNAs that were upregulated in BCBM patients compared to Stage I/II/III breast cancer. Upon further analysis, we identified miR-4732-3p to be upregulated in brain-tropic triple-negative breast cancer (TNBC) cell lines, compared to parental lines. MiR-4732-3p overexpression increased metastatic properties of TNBC cells, including proliferation, migration, invasion, and maintenance of a mesenchymal …

Exploring The Immunologic Consequences Of Atrx Deficiency In Glioma, Benjamin Whitfield

Dissertations and Theses (Open Access)

ATRX is a key chromatin regulator that is frequently mutated across multiple cancer types. One of the most common ATRX-mutated tumor types is the adult-type glioma, IDH-mutant, Astrocytoma. It is known that ATRX mutation leads to increases in DNA damage, replication stress, and global epigenetic regulation at a cell level; however, less is known about the impact of ATRX mutation on immune signaling. Furthermore, little is known about the interaction of ATRX loss with gain-of-function mutations in IDH. In this paper we set out to explore the impact of ATRX loss on immune signaling in gliomas, both in the context …

Stat3, Nf-Κb, And Estrogen Receptor Beta: The Balance Of Inflammation In K-Ras Mutant Lung Adenocarcinoma, Michael J. Clowers

Dissertations and Theses (Open Access)

K-ras mutant lung adenocarcinoma (KM-LUAD) is a difficult-to-treat cancer subtype in which chronic inflammation pervades the tumor immune microenvironment (TIME). Pro-inflammatory pathways dampen the response to treatments, including immune checkpoint inhibitors, necessitating therapies that target this inflammatory signaling network in the TIME. This network is underpinned by interaction and coordination of two inflammatory pathways: signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NF-κB). The balance of these transcription factors determines the degree of anti- vs. pro-tumor immunity, and a skewing towards STAT3 is known to promote tumor development and a pro-tumor TIME. It is also …

Timigp: A Computational Framework To Determine The Tumor Immune Microenvironment Associated With Prognosis And Immunotherapy Response, Chenyang Li

Dissertations and Theses (Open Access)

Accumulating evidence has suggested that the tumor immune microenvironment (TIME) drastically impacts cancer patients’ clinical outcomes, including prognosis and immunotherapy response. However, understanding TIME remains challenging due to its complexity and heterogeneity. In this dissertation, we introduce TimiGP (Tumor Immune Microenvironment Illustration based on Gene Pairs), a computational framework designed to address this challenge. Leveraging single-cell RNA-seq (scRNA-seq) and bulk gene expression data alongside clinical information, TimiGP constructs a cell-cell interaction network that elucidates the relationship between immune cell function and relevant clinical outcomes, such as prognosis and treatment response. With immunological insights, these cell-cell interactions also facilitate the development …

Characterizing And Targeting The Genomic Consequences Of Atrx Deficiency In Glioma, Sharvari Dharmaiah

Dissertations and Theses (Open Access)

Mutational inactivation of histone chaperone ATRX (a-thalassaemia/mental retardation X-linked) represents a defining molecular feature in several cancers, including malignant glioma. As standard of care only leads to transient responses and poor outcomes, there is an unmet clinical need for developing new therapies that target ATRX-deficient glioma. Loss of ATRX gives rise to abnormal G-quadruplex DNA secondary structures at GC-rich sites of the genome, such as telomeric and pericentromeric regions, enhancing replication stress and genomic instability. These mutations are mutually exclusive with TERT promoter mutations, promoting the alternative lengthening of telomeres (ALT) pathway as a telomere maintenance mechanism in ATRX-deficient glioma. …

The Role Of Ganglioside Gd2 And Gd3 Synthase (St8sia1) In The Regulation Of Immune Suppression In Breast Cancer, Bolutyfe Oderinde

Dissertations and Theses (Open Access)

Gangliosides are acidic glycosphingolipids involved in cell adhesion, proliferation, and modulation of signal transduction pathways. It has been reported that tumor-shed gangliosides influence the activity of immune cells including macrophages, NK cells, and T cells. GD3 synthase (GD3S) is the key enzyme that regulates the biosynthesis of the b and c series gangliosides, particularly GD3 and GD2, and studies have shown that GD3S is upregulated in most tumors and plays a role in tumor progression. Similarly, we have previously found GD3S to be significantly upregulated in GD2+ breast cancer stem cells (BCSC) compared to GD2- cells, and the knockdown of …

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 …}

Functional Contribution Of Epithelial To Mesenchymal Transition Program On Krasg12d Targeting Efficacy In Pancreatic Cancer, Ana S. Maldonado

Dissertations and Theses (Open Access)

Functional contribution of epithelial to mesenchymal transition program on KRAS^G12D targeting efficacy in pancreatic cancer

Ana S. Maldonado, BS

Advisory Professor: Raghu Kalluri, M.D., Ph.D.

Pancreatic Ductal Adenocarcinoma (PDAC), a highly aggressive, metastatic, and therapeutically resistant form of pancreatic cancer has been projected to become the second-leading cause of cancer related mortality in the United States. This is driven by its detection difficulty, treatment efficacy, and asymptomatic nature, among other factors. PDAC is driven predominantly by KRAS^G12D mutations, which are responsible for the initial development of pancreatic intraepithelial neoplasia (Pan-IN) lesions, that are further maintained and progressed until …

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 …

Placental Co-Transcriptional Activator Vestigial-Like 1 (Vgll1) Drives Tumorigenesis Via Increasing Transcription Of Proliferation And Invasion Genes, Heather Sonnemann

Dissertations and Theses (Open Access)

Vestigial-like 1 (VGLL1) is a co-transcriptional activator that binds to TEA domain containing transcription factors (TEADs). Its expression is upregulated in a variety of aggressive cancer types, including pancreatic and basal-like breast cancer, and increased transcription of VGLL1 is strongly correlated with poor prognosis and decreased overall patient survival. In normal tissues, VGLL1 is most highly expressed within placental trophoblast cells, which share the common attributes of rapid cellular proliferation and invasion with tumor cells. The impact of VGLL1 in cancer has not been fully elucidated and no VGLL1-targeted therapy currently exists. The aim of this study was to evaluate …

The Role Of Mettl21a In Kras-Driven Cancers, Xiaojie Yang

Dissertations and Theses (Open Access)

Abstract

More than 100 lysine methyltransferases (KMTs) were predicted to be present in the human proteome, and many were implicated in cancer etiology. However, the catalytic activity and substrate specificity for many of these enzymes remain unknown. Our work aimed to explore the role of Methyltransferase like 21A (METTL21A), amember of the little-studied seven β- strand family of candidate lysine methyltransferases (KMTs), and its role in regulating pancreatic ductal adenocarcinoma (PDAC) and lung adenocarcinoma (LUAC) tumorigenesis. Through the meta-analysis of publicly available gene expression datasets, I found that METTL21A is significantly downregulated in PDAC and LUAC versus normal tissue, and …