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The Regulation Of Dna Methylation In Mammalian Development And Cancer, Nicolas Veland

Dissertations & Theses (Open Access)

DNA methylation is an essential epigenetic modification in mammals, as it plays important regulatory roles in multiple biological processes, such as gene transcription, maintenance of chromosomal structure and genomic stability, genomic imprinting, retrotransposon silencing, and X-chromosome inactivation. Dysregulation of DNA methylation is associated with various human diseases. For example, cancer cells usually show global hypomethylation and regional hypermenthylation, which have been implicated in genomic instability and tumor suppressor silencing, respectively. Although great progress has been made in elucidating the biological functions of DNA methylation over the last several decades, how DNA methylation patterns and levels are regulated and dysregulated is …

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 …

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. …

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 …

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 …

B7h6: A Cancer Biomarker For The Development Of Novel Immunotherapy Approaches, Mariana Phillips

Seton Hall University Dissertations and Theses (ETDs)

Cancer-based immunotherapy has led the evolution of biologics that can stimulate immune responses towards tumor eradication. The synthesis of small to intermediate size molecules with the targeting and effector functions of mAb may represent a novel class of immunotherapeutics that may overcome the limitations of their biological counterparts.Towards this objective, B7H6 has been identified as a protein ligand localized on the cell surface of transformed tumor cells. B7H6 binds specifically to the activating receptor NKp30, constitutively expressed on all resting and active NK cells. Upon ligand:receptor binding, B7H6 triggers NK cell activation and release of chemokines and pro-inflammatory cytokines such …

Investigating E2f Independent Cell Cycle Control And Tumor Suppression By Prb, Michael J. Thwaites

Electronic Thesis and Dissertation Repository

Cellular division is primarily controlled at the G1 to S-phase transition of the cell cycle by the retinoblastoma tumor-suppressor protein (pRB). The ability of pRB to restrict S-phase entry is primarily attributed to the repression of E2F transcription factors required to upregulate cell cycle target genes necessary for cellular division. Interestingly, while pRB is disrupted in the vast majority of human cancers, mutations typically target upstream regulators of pRB leading to inactivation through hyperphosphorylation. The rarity of direct pRB mutations suggests that the regulation of the cell cycle by pRB may involve additional mechanisms outside of E2F repression, as this …

Silica Nanoparticles For The Delivery Of Dna And Rnai In Cancer Treatment, Michael Aaron Vrolijk

Graduate College Dissertations and Theses

DNA and interfering RNA (RNAi) – short interfering RNA (siRNA) and micro RNA (miRNA) – are promising new cancer therapies, especially for drug resistant lines. However, they require a delivery system in vivo to prevent degradation and off target effects. Silica based nanoparticles, both solid and mesoporous, are a promising option due to their biocompatibility, ease of preparation and morphology control, reproducibility, and facile addition of functional groups including targeting ligands.

After a brief introduction to cancer treatment and review of the current nanoparticle treatments undergoing clinical trials, this thesis details the many methods explored over the past ten years …

Role Of Erk3 In Regulating Rhogdi1-Paks Signaling Axis, Hitham Abdulrahman Aldharee

Browse all Theses and Dissertations

Extracellular signal-regulated kinase 3 (ERK3) is an atypical protein kinase of the mitogen-activated protein kinase (MAPK) family. In comparison to well-investigated ERK1/2 (classical) MAPKs, much less has been discovered about ERK3 signaling and its cellular functions. Recent studies have shown that ERK3 is overexpressed in various types of cancers such as lung cancer and breast cancer and that ERK3 promotes cancer cell migration and invasion. How ERK3 regulates cancer cell motility and invasiveness, however, is still largely unknown. RhoGTPases, including Rho, Cdc42 and Rac1, play critical roles in regulating cell motility and invasiveness through activating downstream effectors such as p21-activated …

Characterization Of Staphylococcal Nuclease And Tudor Domain Containing Protein 1 (Snd1) As A Molecular Target In Hepatocellular Carcinoma And Non-Alcoholic Steatohepatitis, Nidhi H. Jariwala

Theses and Dissertations

CHARACTERIZATION OF STAPHYLOCOCCAL NUCLEASE AND TUDOR DOMAIN CONTAINING PROTEIN 1 (SND1) AS A MOLECULAR TARGET IN HEPATOCELLULAR CARCINOMA AND NON-ALCOHOLIC STEATOHEPATITIS

Nidhi Jariwala, PhD

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Integrative Life Sciences

Virginia Commonwealth University, 2017

Devanand Sarkar, M.B.B.S., PhD.

Associate Professor, Department of Human and Molecular Genetics

Virginia Commonwealth University

Richmond, Virginia

SND1, a subunit of the miRNA regulatory complex RISC, has been implicated as an oncogene in hepatocellular carcinoma (HCC). Oncoprotein SND1 regulates gene expression at a post-transcriptional level in multiple cancers including hepatocellular carcinoma (HCC). …

Comprehensive Molecular Characterization Of Human Nodal, Scott D. Findlay

Electronic Thesis and Dissertation Repository

Nodal and related ligands are highly conserved members of the TGF-beta superfamily with well-established and essential roles in the early embryonic development of vertebrates, and in cell fate decisions in human embryonic stem (hES) cells. Aberrant NODAL signaling also generally promotes pro-tumourigenic phenotypes and the progression of a wide array of human cancers. Despite being pursued as a potential therapeutic target, many aspects of NODAL’s molecular biology remain poorly understood. This thesis provides a comprehensive characterization of gene expression from the human NODAL locus at multiple levels. First, an intronic NODAL SNP known as rs2231947 was found to be functional …

Characterization Of The Catalytic Ck2 Subunits With Substitutions At Residues Involved In Inhibitor Binding, Paul Desormeaux

Electronic Thesis and Dissertation Repository

CK2 is a constitutively active, ubiquitously expressed and pleiotropic serine/threonine protein kinase that is implicated in many cellular functions including tumorigenesis. CK2 has two catalytic subunits, CK2a and CK2a’, that carry out its function in the cell. Previous studies have indicated that inhibitor-refractory mutants have been effective in recovering residual CK2 activity, in the presence of inhibitors, when compared to wild type CK2. Based on these observations, inhibitor-refractory mutants were created for both CK2a and CK2a’ and tested with various concentrations with two CK2-specific inhibitors, CX-4945 and inhibitor VIII. The CK2a triple mutant (V66A/I174A/H160D) was tested in inducible U2OS Flp-In …

Investigating The Roles Of Δnp63 As A Suppressor Of Migration, Invasion, And Metastasis, Ramon E. Flores Gonzalez

Dissertations & Theses (Open Access)

Cancer is one of the leading causes of death and disease in the world. Considerable resources are spent to study and understand cancer, with the hope of developing new treatments and eventually cures that will help millions of people. Efforts to understand cancer are hindered by its inherent complexity and instability. Nonetheless, understanding the basics of tumor development and progression are the key to focused on studying the role of ΔNp63 in cancer, a p53 family member known to be involved in epithelial development, microRNA biogenesis, and stem cell maintenance. Using the strength of in vivo mouse models, we found …

Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt

USF Tampa Graduate Theses and Dissertations

Tumorigenesis is a multifaceted set of events consisting of the deregulation of several cell-autonomous and tissue microenvironmental processes that ultimately leads to the acquisition of malignant disease. Transforming growth factor beta (TGFß) and its family members are regulatory cytokines that function to ensure proper organismal development and the maintenance of homeostasis by controlling cellular differentiation, proliferation, adhesion, and survival, as well as by modulating components of the cellular microenvironment and immune system. The pleiotropic control by TGFß of these cell intrinsic and extrinsic factors is intimately linked to the prevention of tumor formation, the specifics of which are dependent on …

Characterization Of Numb As A Regulator Of Anaplastic Lymphoma Kinase, Ran Wei

Electronic Thesis and Dissertation Repository

Cellular events rely on protein-protein interactions that are often mediated by modular domains which recognize particular sequence motifs in binding partners. The NUMB protein is the first described cell fate determinant and multifaceted adaptor that is involved in a wide variety of cellular events. NUMB mainly mediates protein interactions via its modular PTB domain. Here we present a systematic investigation of the NUMB-PTB interactome by employing an integrative strategy combining both protein and peptide arrays. We profiled NUMB-PTB binding specificity and interacting proteins genome-wide. The receptor tyrosine kinases (RTKs) are found highly enriched in the interactome, raising the possibility that …

Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung

Open Access Dissertations

Chemotherapy is currently the mainstay of treatment for most cancer patients. Despite its efficacy in eliminating cancer cells, a high percentage of chemotherapy patients eventually relapse or suffer progression of the disease. Immunosurveillance is capable of recognizing and eliminating continuously arising transformed mutant cells, and thus cancer immunotherapy is one of the emerging therapeutic strategies that harnesses the power of the immune system to eradicate chemotherapy-resistant cancerous cells. However, the adverse side effects of chemotherapy impede the therapeutic effects of immunotherapy. Our previous studies demonstrate that lymphoma patients are refractory to clinical immunotherapy because of chemotherapy-induced immune dysfunction. In addition, …

Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman

Open Access Theses

Lung cancer is the leading cause of cancer deaths in the United States, accounting for 27% of all cancer induced deaths1. In an attempt to create a effective targeted therapy for the treatment of lung cancer, a strategy used to treat an activated KrasG12D/+;p53 R172H/+ transgenic lung cancer mouse model was to deliver a known tumor suppressive microRNA (miRNA) to stop tumor growth. The tumor suppressive miRNA let-7 was lentivirally delivered in the form of its primary transcript, pri-let-7a-1, and resulted in increased lung size and inflammation compared to lungs exposed to a control lentivirus. It was identified …

A Requirement For Y841 In Jak3 Enzymatic Activity And Hematopoietic Cancers, George Steven Martinez

Open Access Theses & Dissertations

A medical need exists for successfully treating people afflicted with leukemia, especially those who develop drug resistant forms. Relapse leukemia cases are particularly high within Hispanic populations where this disease is among the most frequently occurring cancer. Fourteen somatic mutations have been reported in Janus tyrosine kinase 3 (Jak3), including M511I and A573V, from patients with various forms of leukemia. To monitor drug sensitivity, a model system was developed. Indeed, many of these mutations have been shown to possess transforming ability in cell lines such as the IL-3 dependent pro-B cell line Ba/F3. As such, Ba/F3 cells were transformed to …

Restriction And Characterization Of Human Breast Cancer Using A Three-Dimensional Embryonic Stem Cell Model, Bridget Mooney

Legacy Theses & Dissertations (2009 - 2024)

Human breast cancer is currently the highest diagnosed form of cancer and the second leading cause of cancer-related deaths in American women. Triple negative breast cancer is of the basal subtype and displays the worst prognosis owing to its highly metastatic properties. Current treatments focused on eradicating breast tumors in lieu of or following local therapy include chemotherapy, hormonal therapy, and targeted therapy. Hormonal therapy is not an option for triple negative breast cancer as it does not contain hormone receptors and there are currently no approved biological targeted therapies. Chemotherapy has proven unsuccessful because triple negative breast cancer is …

Comparative Proteomic Analysis Of Extracellular Vesicles From Prostate Cancer-Derived Cell Lines, Gloria Polanco

Open Access Theses & Dissertations

Prostate cancer (PCa) is the leading non-cutaneous malignancy and the second deadliest among American men. PCa mortality rates among African American men are much higher than any other ethnic group, and the same is true for men of African ancestry world-wide. There is also a lack of reliable diagnostic markers and effective treatment options. Extracellular vesicles (EVs) have been observed to play an important role in cancer processes such as promotion of tumor growth and metastasis. They are also a promising source of diagnostic markers. This study addresses these problems by studying the proteome of EVs derived from PCa cells …

Rna Aptamers For Molecular Chaperones Hsp27 And Hsp90, Sathishkumar Kumar Munusamy

Legacy Theses & Dissertations (2009 - 2024)

Hsp90 and Hsp27 are members of the heat shock protein family of chaperones that perform multiple roles in cellular maintenance through protein folding and inhibition of apoptosis. They are abundantly expressed in cells and are over-expressed during conditions of stress. Hsp90 requires ATP for its chaperone function while Hsp27 self-associates into higher order oligomers enclosing its substrate. Their ability to interact with other proteins or with themselves lies at the heart of their mechanisms. The specific consequences of each of their interactions on global cellular health have not yet been fully discovered. The sheer diversity of proteins that interact with …

Genomic Aberrations At The 3q And 14q Loci: Investigation Of Key Players In Ovarian And Renal Cancer Biology, Punashi Dutta

USF Tampa Graduate Theses and Dissertations

Genomic aberrations are primary contributors to the pathophysiology of cancer [11]. Dysregulated expression of genes located within these aberrations are important predictors of chemoresistance, disease prognosis, and patient outcome [12]. This dissertation is focused on understanding the regulation and/or functions of specific genes located at dysregulated genomic regions such as 3q26 and 14q32 in the biology of ovarian and renal cancer, respectively.

Serous epithelial ovarian cancer (EOC) manifest amplification at the 3q26.2 locus [2], an observation consistent with the cancer genome atlas (TCGA) [13]. The most amplified gene in this region is EVI1 which has been extensively studied in hematological …

Interaction Between Atm Kinase And P53 In Determining Glioma Radiosensitivity, Syed F. Ahmad

Theses and Dissertations

Glioblastoma multiforme (GBM) is the most common primary brain tumor. Studies have shown that targeting the DNA damage response can sensitize cancer cells to DNA damaging agents. Ataxia telangiectasia mutated (ATM) is involved in signaling DNA double strand breaks. Our group has previously shown that ATM inhibitors (ATMi) sensitize GBM cells and tumors to ionizing radiation. This effect is greater when the tumor suppressor p53 is mutated.

The goals of this work include validation of a new ATM inhibitor, AZ32, and elucidation of how ATMi and p53 status interact to promote cell death after radiation. We propose that ATMi and …

Nitric Oxide Synthase Activity And Its Modulation In The Treatment Of Colorectal Cancer, Asim Alam

Theses and Dissertations

The American Cancer Society estimates more than 141,000 new cases of and about 50,000 deaths from colorectal cancer every year. Treatment options include surgery, radiation therapy and targeted therapies such as anti-angiogenics. However, no therapies address the key driving factor of colorectal cancer: inflammation. It is well known that chronic inflammatory conditions such as Crohn’s Disease, ulcerative colitis, diabetes, obesity and cigarette smoking all elevate the risk of developing colorectal cancer. One of the hallmarks of chronic inflammation is the elevated levels of reactive oxygen/nitrogen species (ROS/RNS). A primary source of these ROS/RNS is uncoupled Nitric Oxide Synthase (NOS). Under …

Novel Posttranslational Modification In Lkb1 Activation And Function, Szu-Wei Lee

Dissertations & Theses (Open Access)

Cancer cells display dramatic alterations in cellular metabolism to meet their needs of increased growth and proliferation. In the last decade, cancer research has brought these pathways into focus, and one emerging issue that has come to attention is that many oncogenes and tumor-suppressors are intimately linked to metabolic regulation (Jones and Thompson, 2009). One of the key tumor-suppressors involved in metabolism is Liver Kinase B1 (LKB1). LKB1 is the major upstream kinase of the evolutionarily conserved metabolic sensor—AMP-activated protein kinase (AMPK). Activation of the LKB1/AMPK pathway provides a survival advantage for cells under energy stress. LKB1 forms a heterotrimeric …

Designing A Pore-Forming Toxin Cytolysin A (Clya) Specific To Target Cancer Cells, Alzira Rocheteau Avelino

Masters Theses

Cytolysin A (ClyA) is a member of a class of proteins called pore-forming toxins (PFTs). ClyA is secreted by Gram-negative bacteria, and it attacks a number of mammalian cells by inserting into and forming channels within the cell membrane (Oscarsson J et al., 1999). It has been suggested that ClyA binds to cholesterol (Oscarsson J et al., 1999) and thus can insert into the membranes of many different cell types of eukaryotic origin. In our studies we propose to engineer a ClyA protein that can only attack a small subset of cell types. We propose to engineer ClyA that can …

Augmentation Of Ras-Induced Cell Transformation : A New Role For Mir-200a In Malignancy., Lindsey Erin Becker

Electronic Theses and Dissertations

Cancer is a multistep disease that begins with malignant cell transformation and frequently culminates in metastasis and death. MicroRNAs (miRNAs) are small regulatory 21-25-nt RNA molecules and are frequently deregulated in cancer. The majority of miRNAs are estimated to be co-expressed with neighboring miRNAs as clusters. Many miRNA clusters coordinately regulate multiple members of cellular signaling pathways or protein interaction networks. miR-200a is a member of the miR-200 family, which are known to be strong inhibitors of the epithelial to mesenchymal transition. As such, the tumor suppressive role of miR-200a in oncogenesis has been well studied; however, recent studies have …

Sirna Targeting Of Thymidylate Synthase, Thymidine Kinase 1 And Thymidine Kinase 2 As An Anticancer Therapy: A Combinatorial Rnai Approach, Christine Di Cresce

Electronic Thesis and Dissertation Repository

Thymidylate synthase (TS) is the only de novo source of thymidylate (dTMP) for DNA synthesis and repair. Drugs targeting TS protein are a mainstay in cancer treatment but off-target effects and toxicity limit their use. Cytosolic thymidine kinase (TK1) and mitochondrial thymidine kinase (TK2) contribute to an alternative dTMP-producing pathway, by salvaging thymidine from the tumour milieu, and may modulate resistance to TS-targeting drugs. We have previously shown that TS antisense molecules (oligodeoxynucleotides, ODNs, and small interfering siRNA, siRNA) sensitize tumour cells, both in vitro and in vivo, to TS targeting drugs. As both TS and TKs contribute to cellular …

The Role Of Af9 And Af9-Mediated Protein Interactions In Hematopoiesis And Leukemogenesis, Alyson Anne Lokken

Dissertations

The AF9 protein is one of the most common chromosomal translocation partners of the MLL gene in MLL leukemia. Wild-type AF9 is a member of the pTEFb transcription elongation complex, and interacts with gene regulatory proteins such as AF4/AF5q31, DOT1L, Pc3/CBX8 and BCoR. These interactions are retained in the oncogenic MLL-AF9 fusion protein, and may be required for leukemic transformation.

Using bone marrow progenitor cells isolated from conditional Af9 knockout mice, we examined in vitro differentiation of hematopoietic progenitor cells to the erythroid, myeloid and megakaryocytic lineages in the presence or absence of Af9. Based on previously published studies, we …

Molecular Studies On The Anti-Tumor Effects Of Metal-Based Complexes: Involvement Of The Ubiquitin-Proteasome And Apoptotic Pathways, Sara M. Schmitt

Wayne State University Dissertations

The ubiquitin-proteasome pathway is crucial to normal cellular function, and as such, has been extensively investigated as a potential target for cancer therapeutics. Many compounds have been tested for their proteasome inhibitory ability, including various small peptide aldehydes, and, following the success of cisplatin, several metal-containing complexes. The efficacy of these compounds in preclinical studies ultimately resulted in the development and approval of the first-in-class proteasome inhibitor bortezomib, the use of which, unfortunately, has been hindered by toxicity and resistance. These limitations have led to a massive push toward designing and developing new, less toxic proteasome inhibitors for clinical use. …