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Contribution Of Activating Transcription Factor 3 To Development Of Acinar-To-Ductal Cell Metaplasia, Jelena Toma

Electronic Thesis and Dissertation Repository

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in North America. The highest risk factor for PDAC is recurrent pancreatitis. While the link between PDAC and pancreatitis is unknown, de-differentiation of acinar cells is common to both diseases. Our lab has shown that Activating Transcription Factor 3 (ATF3), a factor upregulated during pancreatic injury, contributes to the development of acinar-to-ductal cell metaplasia (ADM), a precursor phenotype of PDAC. The goal of this study was to identify how ATF3 contributes to ADM. I hypothesize that ATF3 regulates acinar gene expression promoting ADM. We observed decreased ADM development …

Characterization Of The Ubiquitin Ligase, Ube4b, In Endocytic Trafficking, Natalie Sirisaengtaksin, Natalie Sirisaengtaksin

Dissertations & Theses (Open Access)

Endocytosis is a process by which cells internalize membrane proteins to remove them from the plasma membrane, allowing cells to regulate the cell surface expression of transmembrane proteins. In this manner, cellular responses to extracellular cues may be tuned by limiting the number of proteins available at the cell surface. One particular class of proteins, receptor tyrosine kinases (RTK), is internalized upon binding to extracellular ligands during their residence at the cell surface. The epidermal growth factor receptor (EGFR) is an RTK whose trafficking through the endocytic pathway through the cell is well-documented. Stimulation of EGFR with its cognate ligand, …

Identifying The Signaling Mechanisms Of Egfr-Mediated Apoptosis., Nicole Marion Jackson

Electronic Theses and Dissertations

The Epidermal Growth Factor Receptor (EGFR) is a 170-kilodalton transmembrane protein that belongs to the ErbB family of receptor tyrosine kinases. Upon ligand-mediated activation, the EGFR is responsible for cell growth, proliferation, and tissue homeostasis; however, the EGFR is overexpressed in many human malignancies, including MDA-MB-468 cells, a metastatic breast epithelial cell line. Studies within this cell line, and other cell lines characterized with high EGFR levels, have shown that EGF stimulation results in the induction of apoptosis. However, the mechanisms and signaling effectors implicated in this process have yet to be elucidated. The overarching research goal of this dissertation …

Mechanisms Of Ikbke Activation In Cancer, Sridevi Challa

USF Tampa Graduate Theses and Dissertations

Cancer is the second leading cause of death in the USA and it is expected to surpass heart diseases making it important to understand the underlying mechanisms of cancer. The efforts to target single signaling molecule showed little success in increasing the patient survival and it can be due to increased compensation for cell survival by alternative pathway activations. Hence comprehensive understanding of the alternative signaling pathways may help us treat cancer better. Chronic inflammation is attributed to increased risk of cancer and emerging studies show the growing importance of both canonical and non-canonical IκB kinases such as IKKα, IKKβ, …

The Role Of Progesterone Receptor Membrane Component 1 In Receptor Trafficking And Disease, Kaia K. Hampton

Theses and Dissertations--Pharmacology and Nutritional Sciences

The progesterone receptor membrane component 1 (PGRMC1) is a multifunctional protein with a heme-binding domain that promotes cellular signaling via receptor trafficking, and is essential for some elements of tumor growth and metastasis. PGRMC1 is upregulated in breast, colon, lung and thyroid tumors. We expanded the analysis of PGRMC1 in the clinical setting, and report the first analysis of PGRMC1 in human oral cavity and ovarian tumors and found PGRMC1 to correlate with lung and ovarian cancer patient survival. Furthermore, we discovered a specific role for PGRMC1 in cancer stem cell viability. PGRMC1 directly associates with the epidermal growth factor …

Functional And Mechanistic Consequences Of Dual Oxidase 1 Suppression In Lung Cancer, Andrew Charles Little

Graduate College Dissertations and Theses

The NADPH oxidase homolog, dual oxidase 1 (DUOX1), is an H2O2 producing transmembrane enzyme highly expressed in the airway epithelium. DUOX1-dependent redox signaling has been characterized to regulate many homeostatic processes in the lung epithelium, such as host defense, wound healing, and type II immune responses. Intriguingly, DUOX1 has been found to be suppressed in many epithelial cancers, including lung cancer, by hypermethylation of its promoter. Epigenetic silencing of DUOX1 in cancer is paradoxical to the understanding that tumors harbor elevated levels of reactive oxygen species (ROS), suggesting that DUOX1 may be a tumor suppressor.

Since DUOX1 loss occurs in …