Molecular Biology Commons^™

Fibroblast Growth Factor Receptor 4 And R4-Icd Increased Proliferation, Cell Survival And Metastasis In Cholangiocarcinoma, Yamnah Hafeji

Theses & Dissertations

Fibroblast growth factor receptor 4 (FGFR4) is over-expressed in many cancers, including cholangiocarcinoma (CCA). FGFR4 is activated by fibroblast growth factor ligand 19 (FGF19) and plays a critical role in CCA progression. An intracellular cleaved product of FGFR4, referred as R4-ICD (FGFR4 intracellular domain) is also overexpressed in CCA. However, the specific role of R4-ICD in CCA is unknown. In this study, we hypothesized that FGFR4 and R4-ICD play a role in cell proliferation, cell survival and metastasis in CCA. To test this, FGFR4 and R4-ICD were cloned into a cholangiocarcinoma cell line (HuCCT-1) that does not endogenously express FGFR4. …

Design, Synthesis And Evaluation Of Novel Inhibitors Of Type 5 And 10 17Β-Hydroxysteroid Dehydrogenases, Ahmed Morsy

Theses & Dissertations

17β-Hydroxysteroid dehydrogenases (17β-HSDs) are essential enzymes in steroid metabolism. More and more evidence points to the pivotal contributions of these enzymes in various other metabolic pathways. Therefore, the latest research results give new insights into the complex metabolic interconnectivity of the 17β-HSDs with human diseases. This dissertation focuses on the metabolic activities of type 5 and 10 17β-HSDs. More specifically, regarding 17β-HSD5 contributions to the progression of prostate cancer (PCa) and 17β-HSD10 aggravation of amyloid-beta (Aβ)-induced toxicity in Alzheimer's disease (AD).

The second leading cause of cancer-related death in males is PCa, with the highest incidence rate of all cancers …

Development Of In-Silico Pipelines For Identification And Characterization Of Biomarker Panels And Therapeutic Interventions In Gastro-Intestinal (Gi) Cancers, Pranita Atri

Theses & Dissertations

Gastro-intestinal (GI) malignancies, including gastric, colorectal, and pancreatic cancers, have maintained their high overall mortality due to a lack of prognostic and diagnostic biomarkers and potential therapeutic modalities. While efforts have been made to improve both early detection and therapeutic interventions in these cancers, failure of conventional approaches have proven to be a big challenge, and alternate approaches are needed. Computational biology approaches owing to lesser time and more per target success rate offer a unique solution here. The current study explored the use of computational biology techniques to study the various aspects relating to GI malignancies. First, we sought …

Role Of Endocytic Machinery Regulators In Egfr Traffic And Viral Entry, Insha Mushtaq

Theses & Dissertations

STUDY 1: Role of endocytic regulator EHD1 and its binding partner RUSC2 in EGFR traffic

Abstract

Epidermal growth factor receptor (EGFR) is a prototype receptor tyrosine kinase and an oncoprotein in many solid tumors. Cell surface display of EGFR is essential for cellular responses to its ligands. While post activation endocytic trafficking of EGFR has been well elucidated, little is known about mechanisms of basal/pre-activation surface display of EGFR. Here, we identify a novel role of the endocytic regulator EHD1 and a potential EHD1 partner, RUSC2, in cell surface display of EGFR. EHD1 and RUSC2 colocalize with EGFR in vesicular/tubular …

Identification Of Clonal Evolution Pattern And Mutation Event Associated With Relapsed/Refractory Diffuse Large B-Cell Lymphoma Using Next-Generation Sequencing, Cheng Wang

Theses & Dissertations

Diffuse large B-cell lymphoma (DLBCL) is an aggressive lymphoid malignancy. About 30% of DLBCL cases respond poorly to initial treatment and eventually relapse. For these patients, the current treatment regimen is quite limited, and the prognosis is poor. Gene mutations and genetic alterations play an important role in lymphomagenesis. However, the genetic alterations or gene mutations underlying the disease resistance/relapse in DLBCL are still unknown. The clonal evolution during the process of disease progression is elusive as well. Our goal is to study the genetic alterations in DLBCL, particularly paired diagnostic and relapsed/refractory DLBCL, to better understand the mutation landscape …

Characterizing The Critical Role Of Metabolic And Redox Homeostasis In Colorectal Cancer, Danielle Frodyma

Theses & Dissertations

Metabolic alterations are a hallmark of cancer and the mechanism by which these adaptations sustain cancer cell growth are complex and dependent on tissue type. In colon cancer, Peroxisome Proliferator Activated Receptor γ Coactivator 1 β(PGC1��) and Estrogen-Related Receptor α (ERR��) are overexpressed and contribute to tumor growth. Previous studies have shown that PGC1�� and ERR�� regulate many metabolic processes by controlling vital gene expression. Here, we show that PGC1�� and ERR�� drive oxidative phosphorylation and glycolysis in colon cancer cell lines and we evaluated downstream effectors and processes.

A dysfunction in the reductive and oxidative capacity of the cell …

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …

Elucidating The Role Of Ecdysoneless In Mrna Processing, Irfana Saleem

Theses & Dissertations

The mammalian orthologue of the evolutionarily conserved Ecdysoneless (ECD) protein is required for embryogenesis, cell cycle progression and mitigation of ER stress. However, the molecular mechanisms of ECD function in mammalian cells remain unclear. Here, using mass spectrometry analysis of the mammalian ECD interactome, we identified several components of the mRNA export complexes as binding partners of ECD and then characterized the functional interaction of ECD with key mRNA export-related DEAD BOX protein helicase DDX39A and its associated partners. FISH analysis of Poly-A-tailed mRNAs revealed that ECD depletion/deletion blocks the mRNA export from the nucleus to the cytoplasm. We have …

Glycan-Dependent Adherence And Skin Colonization Of Staphylococcus Epidermidis Mediated By The Surface Protein Aap., Paroma Roy

Theses & Dissertations

Skin-dwelling coagulase-negative staphylococci (CoNS), a group of bacteria that includes Staphylococcus epidermidis, has been implicated to promote skin immunity and antimicrobial defense and prohibit colonization of skin by pathogens like S. aureus. As a skin inhabitant, S. epidermidis lives in tight association with corneocytes, the cells that constitute the uppermost layer of the skin epidermis. Yet the molecular mechanism responsible for adhesion of S. epidermidis to corneocytes remains poorly understood. Our study indicated that Accumulation-associated protein (Aap), a cell-wall anchored, fibrillar adhesin mediates bacterial-host interaction, demonstrated by significantly higher corneocyte binding by Aap-positive 1457 mutants as compared to …

Novel Regulatory Roles Of Endocytic Membrane Trafficking Proteins In Mitochondrial Homeostasis, Trey Farmer

Theses & Dissertations

Endocytic membrane trafficking is a basic cell process that is critical for regulating the transport of lipids and proteins. Our lab focuses on the cellular functions and mechanisms of the proteins that regulate these pathways. A key family of regulatory proteins is the C-terminal Eps15 Homology Domain (EHD) protein family. The EHD family includes EHD1-4, which are ubiquitously expressed in mammalian tissues. While these isoforms do have some overlapping functions, each protein also has distinct activities in regulating the shape and fission of membranes throughout the endocytic pathways. Specifically, EHD1 uses ATP hydrolysis to induce constriction and fission of endocytic …

Delivery Of Small Molecule And Rna Using Synthetic Polymeric Micelles And Multifunctional Exosomes For The Treatment Of Type 1 Diabetes, Yang Peng

Theses & Dissertations

Type 1 diabetes is one of the most challenging chronic autoimmune diseases. The destruction and dysfunction of insulin-secreting β cells are the results of inflammatory infiltration and the synergistic effect of multiple immune cells. The aim of this dissertation is to develop novel and reliable therapeutic approaches to advance the treatment of T1D: including chemical modification of a broad-spectrum immunosuppressant, co-application of small molecule based immune intervention and siRNA based β cell preservative therapy, and administration of a PI3K-δ/γ dual inhibitor to specifically target immune cells, utilizing synthetic polymeric micelles or natural produced multi-functional exosomes derived from human bone marrow …

Ecdysoneless, A Novel Regulator Of Ca2+ Homeostasis And Metabolism, Aniruddha Sarkar

Theses & Dissertations

The hallmarks of cancer include sustained proliferation and survival in the face of cellular stresses imposed by the oncogenic drive, as well as metabolic rewiring for tumor growth under adverse nutritional conditions. Adaptive alterations in key biochemical networks that underlie metabolic rewiring represent potential opportunities to develop new therapeutic strategies against cancer.

My thesis focuses on mammalian Ecdysoneless (ECD), a conserved homolog of the fly Ecdysoneless gene product, which engages fundamental cell biological processes of ER stress, Ca²⁺ signaling and metabolism to help sustain the oncogenic drive in tumor cells. Recent studies from our laboratory provide a clear evidence …

Cholesterol Biosynthesis In The Nervous System With An Emphasis On Desmosterolosis, Luke Allen

Theses & Dissertations

Cholesterol biosynthesis is integral to proper neurodevelopment due to the reliance on de novo synthesis of cholesterol in the brain. Disruptions in this process have devastating outcomes for human life characterized by several phenotypic manifestations concomitant with developmental delay. The cholesterol biosynthesis disorder desmosterolosis is an extremely rare disorder with a severe clinical phenotype, however, the models used to study this disease are not well characterized. In addition to genetic disruptions in cholesterol biosynthesis, pharmacological perturbation is an understudied side effect of many commonly prescribed drugs. Here we present a characterization of the sterol profile of the mouse model of …

Brca1 & Ctdp1 Brct Domainomics In The Dna Damage Response, Kimiko L. Krieger

Theses & Dissertations

Genomic instability is one of the enabling characteristics of cancer. DNA damage response pathways are important for genomic integrity and cell cycle progression. Defects in DNA damage repair can often lead to cell cycle arrest, cell death, or tumorigenesis. The activation of the DNA damage response includes tightly regulated signaling cascades that involve kinase phosphorylation and modular domains that scaffold phosphorylated motifs to coordinate recruitment of DNA repair proteins. Modular domains are conserved tertiary structures of a protein that can fold, function, and evolve independently from an intact protein. One of the most common modular domains involved in DNA damage …

Hdac1 Is A Required Cofactor Of Cbfβ-Smmhc And A Therapeutic Target In Inversion 16 Acute Myeloid Leukemia, Lisa E. Richter

Theses & Dissertations

Acute myeloid leukemia (AML) is a neoplastic disease characterized by the uncontrolled proliferation and accumulation of immature myeloid cells. A common mutation in AML is the inversion of chromosome 16 [inv(16)], which generates a fusion between the genes for core binding factor beta (CBFB) and smooth muscle myosin heavy chain (MYH11), forming the oncogene CBFB-MYH11. The expressed protein, CBFβ-SMMHC, forms a heterodimer with the key hematopoietic transcription factor RUNX1. Although CBFβ-SMMHC was previously thought to dominantly repress RUNX1, recent work suggests that CBFβ-SMMHC functions together with RUNX1 to activate transcription of specific target genes.

Targeting the …

The Role Of Reactive Oxygen Species In Regulating Macrophage And Fibroblast Activation Within The Breast Cancer Tumor Microenvironment, Brandon J. Griess

Theses & Dissertations

The tumor microenvironment (TME) is a key determining factor in breast cancer, especially the more aggressive subtype triple negative breast cancer (TNBC). The activated fibroblasts and macrophages within the TME have many tumor promoting functions. Therefore, targeting their activation presents a novel therapeutic approach in TNBC. My work studied the role of reactive oxygen species (ROS) during fibroblast and macrophage activation in breast cancer.

My studies showed that expression of the secreted antioxidant enzyme, EcSOD, is silenced in breast cancer samples, in part, via increased promoter methylation. The re-expression of EcSOD inhibited c-Met activation in the TNBC cell line, MDA-MB231. …

Defining The Role Of Tyrosine Phosphorylation In The Regulation Of Connexin43 In Cardiac Diseases, Li Zheng

Theses & Dissertations

Connexins are integral membrane proteins that oligomerize to form gap junction channels. Ions and small molecules diffuse intercellularly through these channels, allowing individual cellular events to synchronize into the functional response of an entire organ. Gap junction channels composed of Connexin43 (Cx43) mediate electrical coupling and impulse propagation in the normal working myocardium. In the failing heart, Cx43 remodeling (decreased expression, altered phosphorylation state, loss at intercalated discs, and increased presence at lateral membranes) contributes to rhythm disturbances and contractile dysfunction. While there is considerable information regarding key interactions of Cx43 in the regulation of gap junction channels, unfortunately, the …

Characterization Of The Role Of Acetylated Ape1 In Dna Damage Repair And Transcriptional Regulation, Shrabasti Roychoudhury

Theses & Dissertations

Apurinic/apyrimidinic (AP) sites are the most frequently formed DNA lesions in the genome. The primary enzyme to repair AP sites in mammalian cells is the AP endonuclease (APE1), which functions through the base excision repair (BER) pathway. Mammalian APE1 has a unique N-terminal unstructured tail and has both DNA repair and transcriptional regulatory activities. Our lab discovered that APE1 can be regulated via post-translational acetylation of lysine residues 6, 7, 27, 31, and 32. The role of mammalian APE1 in repair has been extensively studied and well characterized. However, the regulatory role of APE1 acetylation (AcAPE1) in the context of …

Identification Of Pathways Required For The Survival Of Inversion(16) Acute Myeloid Leukemia, Yiqian Wang

Theses & Dissertations

Inversion of chromosome 16 [inv(16)] acute myeloid leukemia (AML) generates a fusion gene CBFB-MYH11. Approximately half of inv(16) AML patients eventually relapse mainly due to the existence of leukemia stem cells (LSCs). Previous work using a Cbfb-MYH11 knockin mouse model showed that the LSCs are enriched within CSF2RB^- population. Another gene upregulated by Cbfb-MYH11 encodes the cytokine receptor IL1RL1. Using Cbfb-MYH11 knockin mice, we showed that LSCs exist in multiple sub-populations defined by their immunophenotype, and IL1RL1 is expressed by cell populations with high LSC activity. We also found that treatment of IL-33, the ligand for IL1RL1, promoted …

The Role Of Ros In The Progression And Treatment Of Castration-Resistant Prostate Cancer, Dannah R. Miller

Theses & Dissertations

Prostate cancer is the second leading cause of cancer-related deaths in U.S. men, primarily due to the development of castration-resistant (CR) prostate cancer (PCa), of which there are no effective treatment options. Reactive oxygen species (ROS) plays a critical role in prostate carcinogenesis, including the progression of the CR PCa phenotype. ROS regulates both cell proliferation and apoptosis; a moderate increase in ROS can promote proliferation; however, a substantial rise in ROS levels will result in apoptosis. Oxidase p66Shc is elevated in clinical PCa cells and has been associated with a metastatic phenotype of CR PCa cells, promoting PCa cell …

Developing Targeted Therapy Against Pancreatic Cancer, Garima Kaushik

Theses & Dissertations

Not available.

Delineation Of New Mechanisms Of Dna Double Strand Break Repair, Songli Zhu

Theses & Dissertations

DNA damage is frequently induced in cells by both endogenous and exogenous agents. DNA damage, particular double strand breaks (DSBs) may lead to genomic instability, and the progression of cancer, aging, neurodegeneration, and other human diseases. The cell employs two major DSB repair pathways, including homologous recombination (HR) and Non-homologous end joining (NHEJ), but the detailed mechanisms of DSB repair remain to be further revealed.

In the first part of this study, we characterized a plasmid-based assay to investigate NHEJ repair in Xenopus egg extracts. Our data argued for a preference for the precise repair by the NHEJ machinery and …

Intra- And Inter-Molecular Signaling In A Cardiac Connexin: Role Of Cytoplasmic Domain Dimerization And Phosphorylation, Andrew J. Trease

Theses & Dissertations

As critical mediators of cell-to-cell communication, gap junctions (GJs) are comprised of membrane channels that directly link the cytoplasm of adjacent coupled cells thereby allowing for the passage of ions, small metabolites, and secondary messengers. Each channel is formed by the apposition of two connexons from adjacent cells, each composed of six connexin (Cx) proteins. Each GJ channel functions to promote signal propagation and synchronization of cells and tissues in organs. Furthermore, GJs are essential for proper propagation of cardiac action potentials from one cell to the next, leading to the coordinated contraction and relaxation of heart muscle powering circulation. …

Modulating Hallmarks Of Cholangiocarcinoma, Cody Wehrkamp

Theses & Dissertations

How are cholangiocarcinoma cells different from non-malignant cholangiocytes?

All of the hallmarks of cancer apply- those reported in this dissertation include cell proliferation, migration, apoptosis, and evasion of growth suppression. My studies began with testing how apoptosis might be regulated through embelin, a small molecule reported to sensitize cells to apoptosis by blocking XIAP. My data however revealed that embelin reduced the proliferative capacity in cholangiocarcinoma cells, but did not increase cell death. Malignant cells exhibit dysregulation of microRNA processing and expression. Hence, my studies seeking ways that cholangiocarcinoma eludes apoptosis transitioned to the oncomiR miR-106b, which is overexpressed in …

Elucidation Of The Functions Of Neuropilin 2 In Osteoclasts In Promoting Prostate Cancer Bone Metastasis., Navatha S. Polavaram

Theses & Dissertations

Bone metastasis is one of the major clinical concerns that causes skeletal related malignancies and increased mortality. Bone is one of the preferred sites for metastatic prostate cancer. The metastatic prostate cancer cells interact with bone cells (osteoblasts and osteoclasts) resulting in an imbalance in the bone homeostasis leading to increased activation of osteoblasts over osteoclasts. Our preliminary data indicated a non-tyrosine kinase receptor Neuropilin 2 (NRP2) is expressed in osteoclasts induced by metastatic prostate cancer cells and acts as a negative regulator of osteoclast differentiation and function. We hypothesize that prostate cancer -induced NRP2 expression in osteoclasts is necessary …

Inhibition Of Rad52-Based Dna Repair For Cancer Therapy, Mona Al-Mugotir

Theses & Dissertations

Germline BRCA mutations underlay a significant risk for breast and ovarian cancer that increases in age. BRCA mutations are usually associated with the most aggressive subtypes of these cancers such as triple negative breast cancer and high-grade serous ovarian cancer. Conventional chemotherapeutic or hormonal therapies do not address the molecular deficiencies responsible for their resistance and there is a high rate of recurrence. Targeted therapy that can address the unique molecular features in these subtypes of cancer is the only way to cure the disease or, at the very least, improve patients’ quality of life.

Homologous recombination repair is an …

Muc4 Based Immunotherapy For Pancreatic Cancer, Kasturi Banerjee

Theses & Dissertations

Pancreatic Cancer (PC) is a lethal disease claiming approximately 45000 lives in the US in 2018, and it establishes an elaborate immunosuppressive tumor microenvironment that aids in disease pathogenesis. Immunotherapy has emerged as a strategy to target tumor cells by reprogramming patient’s immune system. Challenges present in PC immunotherapy are: i) identifying a tumor-associated antigen that could be targeted, ii) identifying adjuvants that could efficiently deliver antigens, iii) eliciting robust anti-tumor responses and iv) overcoming peripheral tolerance and immunosuppression elicited by the tumor.

Firstly, we detected circulating autoantibodies to MUC4 present in PC patients and observed that IgM autoantibodies to …

Role Of Ezrin In Colorectal Cancer Cell Survival Regulation, Premila Leiphrakpam

Theses & Dissertations

Colorectal cancer (CRC) is the second most common cause of cancer related deaths in the United States, mainly due to metastasis to the distant organ sites. However, the molecular basis of CRC metastasis is poorly understood. Therefore, identification and characterization of novel potential anti-cancer therapeutic targets CRC is of urgent need. Utilizing a 2D-DIGE proteomics approach ezrin was identified as a protein that is differentially expressed between primary colon tumors xenografts, orthotopically implanted in athymic nude mice, and corresponding and liver metastatic deposits. Ezrin, a cytoskeletal protein belonging to the ezrin–radixin–moesin (ERM) family plays important roles in cell motility, invasion …

Metabolic Reprogramming Of Pancreatic Ductal Adenocarcinoma Cells In Response To Chronic Low Ph Stress, Jaime Abrego

Theses & Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal of all cancers with a 5-year survival rate of only 8.2%. This is because PDAC is diagnosed in its advanced stages and is characterized by radio and chemotherapy resistance. Aggressiveness of PDAC tumors is attributed to its high metabolic phenotype, which is characterized by increased glycolysis rate and lactate secretion, while oxidative metabolism is reduced. These metabolic features are required to fulfill the biosynthetic demands of proliferating PDAC cells. However, this increase in metabolic activity results in acidification of the extracellular space because the dense fibrotic stroma of PDAC tumors limits …

Molecular Mechanisms Of C-Terminal Eps15 Homology Domain Containing (Ehd) Protein Function, Kriti Bahl

Theses & Dissertations

Endocytic trafficking is not only an essential process for the maintenance of cellular homeostasis but also plays a vital role in regulating diverse cellular processes such as signaling, migration and cell division. The C-terminal Eps 15 Homology Domain proteins (EHD1-4) play pivotal roles in regulating distinct steps of endocytic trafficking. Among the EHDs, EHD2 is disparate both in terms of sequence homology (70%) and its subcellular localization at the caveolae. The crystal structure of EHD2 has been solved and it contains an unstructured loop consisting of two proline-phenylalanine (PF) motifs: KPFRKLNPF. However, the other paralogs EHD1, …