Life Sciences Commons^™

Cytotoxic Activity Of Salvia Officinalis Extract Mediated By The Inhibition Of Jak2 In Breast Cancer, Salma Alawadi Dawood

Theses and Dissertations

Background: Breast cancer is the most common type of invasive cancer in women in their forties and fifties. Recent evidence suggests that JAK2/STAT3 signaling is constitutively active in breast cancer. Previous studies suggest that plant extracts, including Salvia Officinalis, have strong cytotoxic effects on breast cancer cells. The differential expression of miRNAs is also strongly linked to cancer development.

Aim: In the current study, we hypothesize that S. Officinalis extract suppresses JAK2 expression and has strong anticancer potential in MCF7 breast cancer cell lines.

Methods: GC-MS analysis showed the presence of flavonoids in dried leaf of …

Evaluation Of Nutrient Digestibility Of Weaned Calves From Early And Late Shedding Dams, Jennifer Keele

Theses and Dissertations

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was …

Crispr-Based Genome Editing Of Caenorhabditis Elegans And Cultured Human Cells, Katie Marie Toperzer

Theses and Dissertations

The fields of genetics and molecular biology have grown exponentially in the knowledge and ability to edit DNA sequences. The discovery of DNA structure in the 1950s and enzymes that are able to make site-specific cuts in the 1970s allowed scientists to harness growth in the field of genetic engineering and develop realistic gene therapies for diseases. In my thesis, I will utilize cutting-edge technology to be the first person at Florida Tech to genetically engineer two different model systems. Using CRISPR, I will study the molecular mechanisms of fertilization by introducing a genetically encoded reporter in C. elegans. Additionally, …

Dna Damage Response Activates The Electron Transport Chain And Oxidative Metabolism By Two Parallel Mechanisms, Shreya Nagar

Theses and Dissertations

The DNA damage response (DDR) is an evolutionarily conserved process essential for cell survival. Major part of DDR is coordinated by DNA damage checkpoint (DDC). In addition to DDC, eukaryotic cells also have DNA replication checkpoint (DRC) that is distinct from the DDC and specifically signals slowly progressing or arrested replication forks. DDR involves stalling or arrest of the cell cycle, initiation of DNA repair, and altered regulation of transcription, translation, and the ubiquitin-proteasome system. DDR also triggers transcription shut-off of histone genes. One of the key outcomes of DDC/DRC activation is the increased synthesis of the deoxyribonucleoside triphosphates (dNTPs), …

Protacs – A Novel And Rapidly Developing Field Of Targeted Protein Degradation, Hannah R. Gatley

Theses and Dissertations

There is a continued need for new technology and strategies for tackling cancer and other diseases, and within the current century a novel therapeutic strategy has emerged in the realm of targeted protein degradation called Proteolysis-Targeting Chimeras (PROTACs). This technology specifically targets and degrades disease-causing proteins via the ubiquitin-proteasome system, and has seen an explosion of research and intrigue in both academia and industry over the past two decades. The diversity of PROTAC classes based on the E3 ligase recruiting ligand and the target protein allows for a universal molecular structure that can be customized for a specific target and …

Kpt-330 Synergizes With Everolimus To Reduce Mtorc1-Overactive Basal-Like Triple-Negative Breast Cancer Brain Metastasis Burden, Aaron D. Valentine

Theses and Dissertations

Triple-negative breast cancer (TNBC), a highly metastatic breast cancer subtype, accounts for approximately 20% of all breast cancer diagnoses. Basal-like TNBC is notably difficult to treat due to the lack of actionable drug targets such as estrogen and progesterone receptors, as well as HER2. Due to the deficiency in TNBC-targeting drugs that are able to cross the blood-brain barrier (BBB) for breast-to-brain metastasis, there is a need to develop novel BBB-permeable treatments. After preliminary testing, KPT-330 (XPO1 inhibitor) and everolimus (FKBP1A/mTOR inhibitor) were selected as drug candidates for this study. Patient-derived xenograft (PDX) models for in vitro and in vivo …

Tgif1 Physiological Levels Limit Β-Cell Distress And Neonatal Diabetes, Creighton J. Friend

Theses and Dissertations

TGIF1 belongs to the superfamily of homeodomain proteins, which regulate a wide variety of biological functions, including cell stemness and specification of cell fate during early development. Perhaps surprisingly, we found that enforced expression in pancreatic progenitor cells during embryogenesis resulted in severe diabetes, hinting at the possibility that TGIF1 might regulate pancreas development. Subsequent genetic experiments targeting β-cells showed that TGIF1 affected β-cell function and homeostasis. Transcriptomic analysis revealed that TGIF1 expression inhibits the expression of essential components of UPR signaling, underscoring a potential mechanism in which TGIF1 disrupts protein folding and secretion. Congruently, TGIF1 expression led to a …

Pre-Clinical Trials With Precision-Medicine Based Therapeutics In Basal-Like Patient-Derived Xenografts, David C. Boyd

Theses and Dissertations

Breast cancer treatments have improved over time, but the diseases seeing the most benefit from these improvements have the estrogen receptor, progesterone receptor, or are positive for HER2. Basal-like breast cancer tends to not have these biomarkers, which necessitates their treatment to be traditional, untargeted therapeutics which are less effective and tend to have harsh adverse effect profiles – this is an important unmet need. These studies utilize a variety of techniques, including tissue culture, viability assays, high-throughput screening, in vivo drug treatments and imaging, pathway analyses, molecular techniques such as Western blot, antibody arrays, RNA sequencing, sc RNA sequencing, …

Nup211 Plays An Important Role In Regulating Mrna Export And Stress Response, Ayana Ikenouchi

Theses and Dissertations

Nup211 is a nuclear pore basket component in Schizosaccharomyces pombe and roles in the gating functions of NPCs. Using RT-qPCR, I found that in nup211-shutoff cells, the transcript levels of genes in mRNA export and stress-response pathways were significantly changed, suggesting nup211 is involved in regulating stress response pathways.

Characterization Of The Responses To Chronic Stress In Caenorhabditis Elegans, Amy Laura Knight

Theses and Dissertations

Exposure to chronic temperature stress influences organismal phenotypes that are important for human health, agriculture, and ecology. In this thesis, the model organism Caenorhabditis elegans was used to study the effects of temperature stress on reproduction and lifespan. It was found that worms demonstrated a rapid shut down in egg-laying between 18-24 hours of exposure to 28°C. Despite this reproductive defect, the overall lifespan of worms was unaffected. At the molecular level, heat shock factor 1 (HSF-1), a regulator of the protective molecular pathway known as the heat shock response (HSR), was identified as important for progeny production during heat …

Development Of New Treatments For Asthma And Neuropathic Pain Based On Ɣ-Aminobutyric Acid A Receptor (Gabaar) Ligands, Nicolas Mark Zahn

Theses and Dissertations

The γ-aminobutyric acid A receptor (GABAAR) is a ligand-gated pentameric chloride channel consisting of several identified subunits: α1-6, β1-3, γ1-3, δ, ε, π, θ, ρ1-3.1-2 Typical arrangement of subunits consists of two α subunits, two β subunits, and one γ subunit.3 GABAARs have two binding sites for the endogenous ligand γ-aminobutyric acid (GABA), between the α and β subunits. GABAARs also have a binding site for positive allosteric modulators, such as benzodiazepines, between the α and γ subunits.4-5 Due to their ability to treat anxiety, epilepsy, insomnia, and muscle relaxation, benzodiazepines are widely prescribed pharmaceuticals.6-7 Still, adverse effects result from …

Repurposing Metformin And Antifolates For The Treatment Of Hepatocellular Carcinoma, Sherouk Mohamed Tawfik

Theses and Dissertations

Hepatocellular carcinoma (HCC), one of the most prevalent types of cancers worldwide, continues to maintain high levels of resistance to standard therapy. As clinical data revealed poor response rates, the need for developing new methods has increased to improve the overall wellbeing of patients with HCC. Due to its safety, wide availability and previously reported anti-cancer effects, metformin (MET) serves to be a possible therapeutic agent when combined with other well-known anti-cancer agents. The aim of this study was to investigate the potential anti-cancer effects of MET, an anti-diabetic agent, when combined with two antifolate drugs: trimethoprim (TMP) or methotrexate …

The Role Of Irf-1 In Spontaneous Mouse Glioma, Aakash B. Vaidya

Theses and Dissertations

Glioblastoma Multiforme has been shown to be one of the deadliest primary brain cancers. One of the reasons why GBM is so deadly, is a unique immunosuppressive tumor microenvironment that promotes GBM growth and progression. Both astrocyte and microglia have been implicated in immunosuppression. In this study, we explored the role of Interferon Regulatory Factor 1 (IRF-1) in astrocytes and glioma cells on the growth of spontaneous glioma tumors. IRF-1 is regulated by the JAK/STAT pathway and induces expression of Programmed death ligand 1 (PD-L1). PD-L1 downregulates immune responses to glioma. We found that IRF-1 had no effect on spontaneous …

Alternatively Spliced Csf3r In Human Health And Disease, Borwyn A. Wang

Theses and Dissertations

Elevated alternative colony stimulating factor 3 receptor (CSF3R) isoforms are observed in myelodysplastic syndromes (MDS) and other myeloid neoplasms, but their role in driving disease progression has not been fully explained. In this study we report on the role of an MDS-associated splicing factor SRSF2 and its effects on the production of Class III and Class IV CSF3R isoforms and granulopoiesis. Class IV add-back in Csf3r-null mice showed impaired neutrophil differentiation with increased number of CFU-G, which largely consisted of metamyelocytes, while Class III showed greater dysgranulopoiesis accompanied by dysmorphic neutrophils. Alternative CSF3R isoforms were elevated in …

Modification Of Culture Medium And Identification Of Microbial Contaminants For Improved In Vitro Propagation Of Freshwater Mussels, Raquel M. Wetzell

Theses and Dissertations

In vitro propagation efforts play an essential role in conserving and restoring threatened freshwater mussel populations by circumventing the need for a fish host. Across a broad range of taxa, transformation is induced with an artificial M199 medium and rabbit serum. However, such formulation may not be sufficient in culturing critical species with more specific physiological requirements. In this study, multiple serum mixtures were tested to improve in vitro transformation of two freshwater mussel species: yellow lampmussel (Lampsilis cariosa) and tidewater mucket (Atlantaconcha ochracea). These species were selected because they parasitize similar fish host species but …

Identifying The Human Homologs Of Yeast Rab Proteins Ypt10 & Ypt11 And A Global-Scale Louse Endosymbiont Genome Variation, Nathaniel P. Smith

Theses and Dissertations

Amyotrophic lateral sclerosis (ALS) is a late-onset fatal neurodegenerative disease that causes loss of upper and/or lower motor neurons, and currently has no treatment or cure available. Over 90% of cases occur spontaneously with unknown causes, highlighting the complexity of the disease, and only 10% of cases are linked to heritable genetic mutations. Numerous ALS-linked genes are conserved through evolution, and model organisms may therefore provide opportunities to understand disease pathology at a molecular or cellular level, proving instrumental in identifying therapeutic targets. ALS subtype 8 (ALS8) is caused by an autosomal dominant P56S mutation in the VAPB gene that …

Evaluating The Biological Activities Of Novel Histone Deacetylase Inhibitors (Hdaci) In Adherent And Nonadherent Tumor Cell Lines, Samer Alanani

Theses and Dissertations

Epigenetic dysregulations are linked to many human diseases including neurodegenerative disorders, immunodeficiencies, cardiac disease, and most notably cancer. Changes in the mechanisms of histone modifications have been recognized as hallmarks of carcinogenesis. One of these modifications is histone acetylation which is regulated by the activities of histone acetyltransferases (HATs) and histone deacetylases (HDACs). The reversible actions of these enzymes govern the acetylome and maintain its balance allowing for activation and repression of gene transcription. However, aberrant overexpression of HDACs in certain tumors is associated with decreased levels of transcription leading to tumor progression and survival. Hence, small-molecule histone deacetylase inhibitors …

Negative Regulation Of The Kinase Lin-45 By The E3/E4 Ubiquitin Ligase Ufd-2, Augustin Deniaud

Theses and Dissertations

The serine/threonine kinase BRAF is a key part of the Ras-Raf-MEK-ERK pathway, an inducer of cell growth, differentiation, and survival. In humans, activating mutations, most commonly BRAF(V600E), have been detected in several cancers, including melanoma and thyroid cancer. In the Caenorhabditis elegans ortholog LIN-45, the equivalent mutation LIN-45(V627E) results in elevated Raf-MEK-ERK signaling. We performed an unbiased genetic screen to identify negative regulators of LIN-45(V627E). Here, we report the identification of the E3/E4 ubiquitin ligase UFD-2, and show it is a negative regulator of LIN-45 protein activity and levels. Loss of UFD-2 leads to accumulation of wild-type LIN-45 protein as …

Divergent Regulatory Roles Of Nurd Chromatin Remodeling Complex Subunits Gatad2 And Chd4 In Caenorhabditis Elegans, Nicole Lynn Golden

Theses and Dissertations

During stress, a protective cellular network known as the heat shock response (HSR) is induced to maintain protein-folding homeostasis, or proteostasis. While the HSR is essential for stress resistance, its misregulation is associated with neurodegenerative disease and cancer. Using the nematode model organism Caenorhabditis elegans, we have identified the chromatin remodeling complex NuRD (nucleosome remodeling and deacetylase) as a novel regulator of the HSR. Here, we begin with a brief introduction of the HSR and chromatin remodeling complexes in C. elegans, prior to presenting our findings in a series of two chapters. In chapter one, we outline a set of …

Distinct Spatiotemporal Regulation Of The Cytoprotective Heat Shock Response In Caenorhabditis Elegans, Rosemary Nadine Plagens

Theses and Dissertations

Every organism studied to-date utilizes the heat shock response (HSR) to maintain protein-folding homeostasis (proteostasis) during temperature or other protein-folding stress. The HSR has been well characterized using acute heat stress (HS) in single-celled models, but less is known about how distinct cell types and tissues respond to HS. Furthermore, how metazoans respond to prolonged HS at the molecular level remains relatively unexplored. The model organism C. elegans, with its genetic tractability and distinct tissues and behaviors, has been used extensively in the field to characterize the acute HSR, but with considerable variability across labs regarding HS temperature and duration. …

Herbal Extracts As Neuroprotective Agents In An In-Vitro Model Of Aluminum Neurotoxicity, Nada Ezzelarab

Theses and Dissertations

Background: Aluminum toxicity due to environmental or industrial exposure, medical applications, or from cooking utensils is a serious medical problem. The current study aims to investigate three herbal extracts: pomegranate peel extract, Achillea fragrantissima extract, and papaya fruit extract to combat this neurotoxicity.

Methods: Chemical characterization of the three extracts were evaluated using HPLC MS while their neuroprotective activity was assayed using MTT assay on SHSY5Y cells and nitric oxide levels.

Results: Using HPLC-MS chromatography, we have identified twenty-one compounds in the hydro-alcoholic Achillea fragrantissima, seventeen were determined in the pomegranate peel, eleven were assessed in the Carica papaya …

Reducing Seed Coat Fiber Content And Pod Shatter, And Engineering Medium Chain Fatty Acids-Containing Oil, In The Oilseed Crop Pennycress ( Thlaspi Arvense L. ), Maliheh Esfahanian

Theses and Dissertations

The overall goal of this thesis was to genetically improve agronomic traits of pennycress (Thlaspi arvense L.; Field Pennycress) and demonstrate the production of value-added designer seed oils to domesticate pennycress and enable its establishment as a new winter annual oilseed/meal/cover crop to be grown in temperate regions of the world. In the U.S. Midwest, pennycress can be double cropped on existing farmland during the time between corn harvest and subsequent planting of soybeans the following spring. Pennycress has the potential to produce 2,000 lbs/acre seeds, which at 33% by weight oil content and 20% protein, would yield 85 gallons/acre …

Evaluation Of The Anticancer Potential Of Alchemilla Vulgaris Extract Against Human Neuroblastoma Cells, Yomna Moqidem

Theses and Dissertations

Neuroblastoma is one of the most challenging pediatric tumors that present heterogeneity in prognosis and survival despite intensive treatment protocols. Therefore, there is an urge to develop novel and more potent anticancer drugs. Medicinal plants have recently gained worldwide attention due to their variable activities, wide availability, and cost-efficiency. Accordingly, this study attempted to identify novel plant extracts that could show potential anticancer properties against neuroblastoma. In this study, Alchemilla vulgaris (A.vulgaris) ethyl acetate extract was prepared and evaluated for its anticancer potential against SH-SY5Y Human neuroblastoma cell line. The Phenolic content of the prepared extract was characterized …

Characterizing Ferroptosis Pathways In In Vitro Motor Neuron Models, Alejandra Martinez

Theses and Dissertations

Ferroptosis is a non-apoptotic regulated form of cell death driven by the toxic accumulation of lipid peroxides and the presence of iron. The mechanism by which ferroptosis operates requires further investigation; here I will discuss the findings regarding the role of ferroptosis in different cellular models as well as the genes that may be involved with either promoting or hindering the ferroptotic pathway. NSC-34 is a hybrid cell line of neuroblastoma and primary spinal cord cells that can be differentiated into a motor neuron-like state allowing the characterization of ferroptosis in two distinct cellular conditions. Additionally, iNIL cells are a …

Comparison Of Semi-Automated And Manual Differential Separation Methods For Mock Sexual Assault Samples, Stephanie Rink

Theses and Dissertations

In the event of a sexual assault, separation of suspect from victim DNA is possible through differential extraction if the evidentiary mixture consists of female epithelial cells and male spermatozoa. The basis of differential extraction is the differing properties of epithelial and sperm cell membranes, specifically the comparative sturdiness of the proteins making up the sperm head containing the male DNA. Effective retrieval and separation of male and female DNA fractions is important in generating high-quality STR profiles that can be utilized in identifying suspects in a sexual assault case. Differential extraction has been conventionally performed using Proteinase K (PK) …

Microrna In The Mammalian Growth Plate: Matrix Vesicles And 1Α,25-Dihydroxyvitamin D3, Niels C. Asmussen

Theses and Dissertations

Growth plate chondrocytes are the driving force of long bone elongation and they accomplish this vital task, in part, by producing, remodeling, and finally mineralizing the cartilage tissue that makes up the growth plate. This mineralized tissue is turned over again as bone forming cells invade and began the process of turning mineralized cartilage into bone. Chondrocytes undergo a distinct series of observable phases as they move through this process transitioning from a stage of proliferation to one of hypertrophy and finally capillary invasion. Chondrocytes produce matrix vesicles (MVs) that they release into the growth plate and that attach to …

A Mechanism Behind The Mechanotransduction Of Surface Characteristics In Osteoblasts, Otto J. Juhl Iv

Theses and Dissertations

Biomaterials for use in bone regeneration and healing range from metal and metal alloy implants to hydrogel-based solutions. These materials can be optimized to increase bone healing and integration by improving the mechanical and biological properties. Regardless of the material itself, the cell-substrate interaction is key to the success of the biomaterial once implanted. Substrate surface characteristics such as roughness, wettability, and particle density are well-known contributors to a substrate’s overall osteogenic potential, and therefore the substrate's overall success. Unfortunately, it is still unknown how these substrate surface characteristics are transduced into intracellular signals by cells, preventing specific tailoring of …

Impact Of Targeting Glycosylated Ceramides On Tumorigenic Properties, And Characterization Of Sphingolipids In Head And Neck Tumors, Katherine E. Hylton

Theses and Dissertations

Sphingolipids play a crucial role in signaling, membrane structure, and migration, making them important molecules in cancer development, metastasis, and drug resistance. While some sphingolipids have been associated with pro-apoptotic or pro-survival behaviors, the role of many sphingolipids in cancer remains poorly defined. Chapter 1 of this study investigated the impact of three enzymes that compose most of the ceramide to Lc3 ceramide pathway – UGCG, GBA, and B3GNT5 – and how their alteration impacts chemoresistance and basal membrane invasion in vitro. It was found that the CΒE-induced inhibition of GBA, which converts glucosylceramide to ceramide, has no effects on …

Prolactin Drives A Dynamic Stat5a/Hdac6/Hmgn2 Cis-Regulatory Landscape Exploitable In Er+ Breast Cancer, Justin M. Craig

Theses and Dissertations

The hormone prolactin has been implicated in breast cancer pathogenesis and regulates chromatin engagement by the transcription factor, STAT5A. STAT5A is known to inducibly bind promoters and cis-regulatory elements genome-wide, though the mechanisms by which it exerts specificity and regulation of target gene expression remain enigmatic. We previously identified HDAC6 and HMGN2 as cofactors that facilitate prolactin induced, STAT5A mediated gene expression. Here, multi-condition STAT5A, HDAC6, and HMGN2 ChIP-seq with parallel condition RNA-seq are utilized to reveal the cis-regulatory landscape and cofactor dynamics underlying prolactin stimulated gene expression in breast cancer. We find that prolactin regulated genes are …

The Role Of Autophagy And Senescence In The Responses Of Non-Small Cell Lung Cancer Cells To Chemotherapy And Radiation, Nipa H. Patel

Theses and Dissertations

Cancer-associated deaths account for the second-highest mortality rates in the United States. Primary modalities of treatment often include surgery, radiation, and chemotherapy, and may also incorporate targeted therapy and immunotherapy. However, resistance to these treatments remains high, resulting in disease reoccurrence and poor survival rates. While apoptosis or cell death of tumor cells is the ideal outcome for anti-cancer therapy, this is often not the case, and in fact cancer cells may upregulate several pathways, such as autophagy and senescence, as a means to undergo alternative cell fate and evade apoptotic cell death. An essential tumor suppressor gene, TP53, …