Cell and Developmental Biology Commons^™

Bacterial Association Networks From Healthy And Cancer-Associated Gut Microbiomes, Mark Loftus

Electronic Theses and Dissertations, 2020-2023

The human gastrointestinal tract is colonized by a diverse community of symbiotic microorganisms, mainly bacteria, that are known to play essential roles in maintaining the health of their human host. Disruption of this bacterial community has been associated with numerous diseases, including Colorectal Cancer (CRC). CRC is one of the leading causes of cancer-related deaths worldwide. As such, focus has been placed on the modulation of the bacterial community within the cancer-associated gut microbiome as the next step in possible CRC treatment and prevention strategies. To use the bacterial community for these purposes, a better understanding of the associations that …

Regulation Of Actin Assembly, Mechanics, And Structure By Intracellular Environmental Factors, Nicholas Castaneda

Electronic Theses and Dissertations, 2020-2023

The assembly, mechanics, and structure of actin cytoskeleton are critical for eukaryotic cellular processes such as structural support, cellular motility, and intracellular transport. Actin assembly occurs in crowded intracellular environments containing many ions and macromolecules. While the individual roles of cation and crowding on actin assembly and mechanics are well established, how the combined cation and crowding effects modulate the formation, mechanics and structural transitioning of actin filaments and bundles are not fully understood. Here, we investigate the impacts of various cation and crowded environments on the bending stiffness, length, organization, secondary structure, and kinetics of actin filaments and bundles. …

The Role Of Notch1, Il-6 And Mir-146a In Inflammation And Infection In Crohn's Disease Non-Responders To Anti-Tnf-Alpha Therapy, Esra'a Keewan

Electronic Theses and Dissertations, 2020-2023

Despite the extensive research on Notch signaling involvement in inflammation, its role in macrophage response in autoimmune diseases and defense mechanisms against bacterial infection such as Mycobacterium avium paratuberculosis (MAP) remains unknown. In this study, we investigated the molecular role of Notch-1 signaling and its downstream modulation in the macrophage response during infection and disease treatment. We demonstrated that MAP infection significantly upregulated Notch-1 and IL-6, which hijacked myeloid cell leukemia sequence-1 (MCL)-1 dependent inhibition of apoptosis and caused chronic MAP persistence and significantly led to successive inflammation. Blocking Notch signaling with gamma-secretase inhibitor (DAPT) decreased MAP survival and burden, …

All Nuts And No Bolts: The Evolution Of Undergraduate Research At A Small State School, James Hawker

Florida Statewide Symposium: Best Practices in Undergraduate Research

In fall of 2017, students first started doing research with their biology instructor, and just a few terms later, two students have earned Portz Interdisciplinary Fellowships. In some ways, the program is going well with students participating in high numbers, but organizers still have questions about the “nuts and bolts” of establishing the program within the institution. Enthusiasm is high! However, key metrics are not being tracked and the workload needs to be distributed more evenly. The organizers will be talking with the audience about different ways to integrate UGR into the institution.

Investigation Of The Cell-Cycle Dependent Activity Of The Brca1-Rbbp8 Complex For Homologous Recombination, Jil Shah

Honors Undergraduate Theses

When cells undergo mitosis, they must replicate all six billion base pairs of DNA within the nucleus. With the sheer volume of information, it is impossible to replicate with 100% accuracy each time. Homologous recombination (HR) is one of many mechanisms the body has developed to correct and repair replication errors to DNA. HR is specific to double-stranded breaks to DNA, and it requires a sister chromatid to preserve the genetic code. BRCA1 and Rbbp8 interact to form a complex that is heavily involved in this process. Although there is a strong consensus about the involvement of these proteins in …

Evaluating Lactobacillus Acidophilus As A Model Organism For Co-Culture Cancer Studies, Samuel A. Mikhail

Honors Undergraduate Theses

The causality dilemma between dysbiosis and cancer has given rise to numerous studies both exploring the mechanisms behind cancer progression and the associative shifts in the microbiota upon carcinogenesis. Aside from the hallmark study of Dr. Barry Marshall in establishing the true causal relationship between Helicobacter pylori and gastric adenocarcinoma, studies have only been successful in adding associative links of carcinogenesis mediated by bacteria to the literature. The current field is limited in its ability to establish causative relationships, and further work is needed to construct a reference community whose physiological responses reflect global community responses. In this thesis, the …

Characterization Of Cytokeratin 8 In Cancer, Daniel S. Leventhal

The Pegasus Review: UCF Undergraduate Research Journal

A Cytokeratin 8 (K8)/Green Fluorescent Protein (GFP) fusion construct was created to better understand the behavior of K8 within cancer cells. This intermediate filament (IF) protein is a member of the cytoskeletal gene family, along with actin and tubulin. IFs are normally expressed in a tissue-specific and differentiation-dependent manner, in which their role is more supportive than essential to the cell. Such roles include rigidity of cellular shape, protein trafficking, cellular locomotion, and cell-signaling platforms. K8 mutation, over-expression, and aberrant post translational modifications have been observed in various carcinoma cell lines to be the cause of several phenotypes, including apoptosis …

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 …

The Identification And Segmentation Of Astrocytoma Prior To Critical Mass, By Means Of A Volumetric/Subregion Regression Analysis Of Normal And Neoplastic Brain Tissue, Lyn Higgins

Electronic Theses and Dissertations

As the underlying cause of Glioblastoma Multiforme (GBM) is presently unclear, this research implements a new approach to identifying and segmenting plausible instances of GBM prior to critical mass. Grade-IV Astrocytoma, or GBM, is an aggressive and malignant cancer arising from star-shaped glial cells, or astrocytes, where the astrocytes, functionally, assist in the support and protection of neurons within the central nervous system and spinal cord. Subsequently, our motivation for researching the ability to recognize GBM is that the underlying cause of the mutation is presently unclear, leading to the operative that GBM is only detectable through a combination of …

Deciphering The Role Of Adrenergic Hormones In Embryonic Cardiac Calcium Signaling And Metabolism, Jessica Peoples

Electronic Theses and Dissertations

The adrenergic hormones norepinephrine (NE) and epinephrine (EPI) are critical regulators of mammalian cardiovascular physiology. NE and EPI mediate stress responses to enhance cardiovascular function, however dysregulation of adrenergic signaling leads to heart failure, congenital heart malformations, and sudden cardiac death. Adrenergic hormone-expressing cells were found in the early embryonic heart, and NE has been determined essential for embryonic cardiac development. Despite extensive work in adults, the regulatory roles and adrenergic targets of these hormones during embryonic cardiac development have not yet been fully determined. Prior transcriptomic studies from our lab showed that expression of signal transduction and metabolic genes …

The Subject Librarian Newsletter, Biology, Spring 2017, Sandy Avila

Libraries' Newsletters

No abstract provided.

The Effect Of K562-Il21-2 Plasma Membrane Particles On The Proliferation Of Natural Killer Cells To Fight Cancer, Michelle Prophete

Honors Undergraduate Theses

Immunotherapy has emerged as a current and future paradigm of cancer treatment, which utilizes the body’s immune system to eradicate cancer. Natural Killer (NK) cells as part of the innate immune system have immense potential in their anti-tumor cytotoxic activities and host cell surveillance properties. NK cells comprise approximately five to fifteen percent of peripheral blood lymphocytes and can be proliferated in vitro using recently developed methods with co-cultures with feeder cells (derived from engineered tumor cells) or plasma membrane (PM) particles, produced from the fore mentioned feeder cells, in combination with soluble cytokines. For efficient growth and maintenance of …

The Response Of Satellite Glial Cells To P2x7 Receptor Activation, Christina D. Kursewicz

Honors Undergraduate Theses

Satellite glial cells (SGCs) surround the cell bodies of neurons of the peripheral nervous system, including those of the sensory ganglia. Their close apposition to the neuronal soma allows for bi-directional communication between neurons and SGCs, which are thought to regulate neuronal activity. After nerve injury, SGCs in the dorsal root ganglia contribute to neuropathic pain. Although the mechanisms are not fully understood, SGCs show increased coupling via gap junctions, and communicate with the neuron via bi-directional purinergic signaling after nerve injury. The increased coupling between SGCs and neurons may have implications for chronic pain following peripheral nerve injury. In …

An Rnai Screen To Identify Components Of A Polyamine Transport System, Adam J. Foley

Honors Undergraduate Theses

Polyamines, specifically putrescine, spermidine, and spermine, are small cationic molecules found in all organisms. Cells can biosynthetically make these molecules, or alternatively, they can be transported from the extracellular environment. Malignant cells have been shown to require relatively high amounts of polyamines. There is a chemotherapeutic agent, DFMO, used to block the biosynthesis of polyamines. Many malignant cells can circumvent DFMO therapy by activating their transport system. A potential solution is to simultaneously block biosynthesis and transport of polyamines. However, little is known about the polyamine transport system in higher eukaryotes.

This thesis aims to add to the basic biological …

Alpha-Synuclein: Insight Into The Hallmark Of Parkinson's Disease As A Target For Quantitative Molecular Diagnostics And Therapeutics, Baggio A. Evangelista

Honors Undergraduate Theses

Parkinson’s disease (PD) is the second-most common neurodegenerative disease after Alzheimer’s disease. With 500,000 individuals currently living with Parkinson’s and nearly 60,000 new cases diagnosed each year, this disease causes significant financial burden on the healthcare system - amassing to annual expenditures totaling 200 billion dollars; predicted to increase through 2050. The disease phenotype is characterized by a combination of a resting tremor, bradykinesia, muscular rigidity, and depression due to dopaminergic neuronal death in the midbrain. The cause of the neurotoxicity has been largely discussed, with strong evidence suggesting that the protein, alpha-Synuclein, is a key factor. Under native conditions, …

Identifying The Effects Of A Human Dynein Mutation On Gfp-Rab7 Axonal Transport In Embryonic Mouse Neurons, Natalie E. Wilson

Honors Undergraduate Theses

The first dynein mutation found in humans that caused disease was a cytoplasmic dynein 1 heavy chain (DYNC1H1 in humans) p.His306Arg mutation, first described by Weedon et al. in 2011. This mutation caused Charcot-Marie-Tooth (CMT) subtype 2O. CMT has a prevalence of approximately 1 in 2500 people, making it the most common hereditary neuromuscular disorder. Cytoplasmic dynein 1 is used by eukaryotic cells for minus-end directed microtubule-based transport of cargo. One such cargo is Rab7, a late endosomal marker. The purpose of this study is to identify the effects of this mutation on the transport of GFP-tagged Rab7 cargo in …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …

Chaperonin Containing Tcp1 (Cct) As A Target For Cancer Therapy, Ana Carr

Electronic Theses and Dissertations

Treatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the CCT2 subunit is highly expressed in breast cancer and could be therapeutically targeted. To determine whether CCT is a marker of disease progression in other cancers, we analyzed CCT2 gene …

Novel Cytokine Signaling And Molecular Therapeutic Strategy In Pancreatic Cancer, Sarah Gitto

Electronic Theses and Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is highly chemo-resistant and has a five year survival rate of < 8%. Risk factors of pancreatic cancer, such as chronic pancreatitis, help to elicit a pro-tumor immune response, and highly fibrotic environment that promotes tumorigenesis. To study how chronic pancreatitis promotes cancer initiation, traditional KRasG12D mice and double mutant Akt1Myr/KrasG12D mice were used to model microenvironment changes. Akt1Myr/KrasG12D mice were more susceptible to chronic tissue damage, accelerated tumor development and metastatic disease. These mice exhibited histological changes consistent with immune cell privilege, where M2 macrophages and non-cytotoxic eosinophils were co-localized with fibrotic regions. IL-5 expression was up regulated in pancreatic cells undergoing acinar to ductal metaplasia and then diminished in advanced lesions. Tumor cells treated with IL-5 exhibit increased migration and activation through STAT5 signaling. Collectively, the results suggest that eosinophils, which are responsive to IL-5, are key mediators in the pancreatic environment subjected to chronic inflammation and injury. Current therapeutics fall short in increasing patient survival. There remains an urgent need for innovative treatments and thus we tested difluoromethylornithine (DFMO) in combination with a novel polyamine transport inhibitor, Trimer44NMe, against Gemcitabine-resistant PDAC cells. Prior clinical failures when targeting polyamine biosynthesis with DFMO monotherapy may be due to tumor escape via an undefined polyamine transport system. In pancreatic tumor cells DFMO alone and with Trimer44NMe significantly reduced PDAC cell viability by inducing apoptosis or cell cycle arrest. In vivo orthotopic PDAC growth with DFMO treatment resulted in decreased c-Myc expression, a readout of polyamine pathway dysfunction. Moreover, dual inhibition significantly prolonged survival of tumor-bearing mice, and increased M1 macrophage infiltration and reduced FoxP3 expression. Collectively, these studies demonstrate that targeting polyamine pathways in PDAC is a promising immunomodulating therapy that increases survival.

The Subject Librarian Newsletter, Biology, Fall 2016, Sandy Avila

Libraries' Newsletters

No abstract provided.

Screening For Anticancer Agents To Inhibit Mitotic Kinases And Proliferation Of Metastatic Prostate Cancer Cells, Khoa Nguyen

Honors Undergraduate Theses

Current treatments for prostate cancer (PCa) are marred with high relapse frequency and development of progressively aggressive cancers; developing new treatment options for PCa remains crucial. In this project, a series of synthetic compounds based on natural products will be screened to identify inhibitors for Aurora-A kinase (Aur-A). Aur-A facilitates centrosome separation and bipolar spindle formation during mitosis. Aur-A is overexpressed in metastatic PCa cells, and is a good candidate for targeted therapies. Compound libraries are designed using natural compounds that contain simple structural elements as starting points for developing drug like libraries. High-throughput screening of these libraries will be …

Prostasin Is Expressed In Benign Prostatic Hyperplasia And Regulates Cell Proliferation And Invasion Via Inos, Icam-1, And Cycli, Meghan Hatfield

Electronic Theses and Dissertations

Prostasin is expressed in normal prostate epithelial cells but down-regulated in prostate cancers, while prostasin re-expression in invasive prostate cancer cells reduced invasion. We examined prostasin expression and function in benign prostatic hyperplasia (BPH). We evaluated prostasin expression in 12 BPH specimens by immunohistochemistry, and evaluated the impact of prostasin silencing by siRNA on the expression of the inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), and cyclin D1, as well as on cell proliferation and invasion, using the BPH-1 human prostate epithelial cell line model. Prostasin expression was localized in the glands of BPH tissues by immunohistochemistry, in …

Role Of Transient Receptor Potential Canonical-6 (Trpc6) Channel In Metastasis Of Glioblastoma Multiforme, Rajarajeshwari Venkataraman

Electronic Theses and Dissertations

Glioblastoma multiforme (GBM) is one of the extremely fatal brain tumors. The main reason that makes it so lethal is its capability to invade and spread to other parts of CNS producing secondary tumors. Among other factors hypoxia, reduced oxygen availability, is linked to higher metastatic potential of cancers. Hypoxia causes numerous changes in genome and proteome of the cell. These changes help a normal cell to adapt to nutritional deficiency, but the same changes can increase the malignancy and metastasis in tumor cells. Extensive research by a number of curious scientists reveal that various pathways involving numerous proteins cross-talk …

Mechanism Of Action And Regulation Of Membrane Serine Protease Prostasin In The Prostate And Prostate Cancer, Mengqian Chen

Electronic Theses and Dissertations

The glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin (PRSS8) is expressed at the apical membrane surface of epithelial cells and acts as a suppressor of tumor invasion when re-expressed in highly invasive human prostate and breast cancer cell lines. To better understand the molecular mechanisms underlying the anti-invasion phenotype associated with prostasin re-expression in prostate cancer cells, we expressed wild-type human prostasin or a serine active-site mutant prostasin in the PC-3 human prostate carcinoma cells. Molecular changes were measured at the mRNA and the protein levels. The expression of several invasion-promoting molecules is regulated by prostasin re-expression, mediated by a protein-level down-regulation …

Lim Kinase 1 Modulates Expression Of Matrix Metalloproteinases And Associates With Gamma-Tubulin: Dual Role In Invasion And Mito, Tenekua Tapia

Electronic Theses and Dissertations

LIM kinase 1 (LIMK1) is a unique dual specificity serine/threonine kinase containing two N-terminal LIM domains in tandem, a PDZ domain and a C-terminal catalytic domain. LIMK1 is involved in modulation of actin cytoskeleton through inactivating phosphorylation of the ADF (actin depolymerization factor) family protein cofilin. Recent studies have shown that LIMK1 is upregulated in breast and prostate cancer cells and tissues, promotes metastasis in animals and induces acquisition of an invasive phenotype when ectopically expressed in benign prostate epithelial (BPH) cells. Furthermore, overexpression of LIMK1 was associated with altered sub cellular localization of the membrane type 1 matrix metalloprotease …