Cell and Developmental Biology Commons^™

An Analysis Of Cellular And Tissue Function Of Lipin In Drosophila Melanogaster, Judah Christian Scott

Graduate Theses and Dissertations

Regulation of energy expenditure and energy storage is a key characteristic of life. Numerous enzymes play a crucial role in regulating energy metabolism. Lipins are a highly conserved family of proteins that function in both lipid synthesis and gene regulation. In the glycerol-3 phosphate pathway, lipins act as a phosphatidate phosphatase (PAP) producing diacylglycerol. In gene regulation, lipins act as transcriptional co-regulators of metabolic genes. The enzymatic PAP activity occurs in the cytoplasm; however, for lipins to function as gene regulators, they must translocate into the nucleus. Nuclear translocation is facilitated by the nuclear localization signal (NLS) within the protein. …

Thymosin Beta-4: A Novel Treatment For Acanthamoeba Keratitis, Victoria A. Murphey

All Theses

Acanthamoeba keratitis (AK) is a severe corneal infection caused by the free-living amoeba, Acanthamoeba. Both stages of its life cycle (trophozoite and cyst) cause infection, primarily in contact lens wearers. It is often misdiagnosed, leading to delayed treatment and poor clinical outcomes. Current treatment options for AK rely on anti-amoebic agents that are toxic to corneal epithelial cells. Further, no single drug can eliminate both forms of the amoeba. Approximately 30% of all AK infections require a corneal transplant.

Thymosin beta-4 (Tβ4) is a G-actin binding protein synthesized in almost all human cells, including corneal epithelial cells. Tβ4 exhibits …

Therapeutic Vulnerabilities Of Venetoclax Resistant Chronic Lymphocytic Leukemia And Novel Treatment Strategies Targeting Bcl2/Bcl-Xl, Daisy Y. Diaz-Rohena

Dissertations and Theses (Open Access)

Despite major advancements in the management of chronic lymphocytic leukemia (CLL), drug resistance remains a major challenge. CLL resistant to venetoclax (VEN) have limited available therapeutic options, especially when the leukemic cells have dysfunctional p53 and have relapsed on Bruton’s tyrosine kinase inhibitors (BTKi). The broad hypothesis of this thesis is that VEN-relapsed CLL exhibits altered dependence on BCL2 family members, which can be exploited for therapeutic benefit. I profiled 28 CLL samples collected from 15 patients either at baseline or at relapse following VEN treatment, which was administered in combination with a BTKi or sequentially as monotherapy after a …

Ascl2 Positive Tumor Cells Modulate The Response Of Metastatic Colorectal Cancer To Mapk-Targeting Therapy, Oscar Eduardo Villarreal

Dissertations and Theses (Open Access)

Colorectal cancer (CRC) is the second leading cause of cancer related deaths with nearly a quarter of patients presenting with metastatic disease at the time of their diagnosis. Therapeutic management of metastatic CRC continues to be a major challenge due to therapy resistance and disease heterogeneity. Due to its central role in tumorigenesis, CRC is commonly treated with MAPK pathway inhibitors (MAPKi). However, clinical trials repeatedly demonstrates that durability of benefit is short-lived in many patients. While genomic mechanisms of acquired resistance have been described, they explain a minority of patients, and further research is needed to determine the underlying …

Identification Of Mitochondrial Defects And Metabolic Consequences In Lynch Syndrome-Related Endometrial Cancer, Mikayla Bowen

Dissertations and Theses (Open Access)

Lynch syndrome (LS), defined by mutations in DNA mismatch repair genes including MSH2, carries a 60% lifetime risk of developing endometrial cancer (EC). Mismatch repair deficiency (MMRd) causes hypermutability, which is assumed to be the main driver of LS-related EC development. However, incomplete penetrance of EC development in women with LS suggests that other modulators are at play. The broad hypothesis of this dissertation is that MMRd causes consequences beyond hypermutability to impact LS-related EC development. Recent studies utilizing our lab’s Msh2-deficient mouse model for LS-EC revealed mitochondrial dysfunction in EC pathogenesis. This new insight led to the …

Developing Novel Therapies Targeting The Tumor Microenvironment Of Aggressive Breast Cancer, Lan T H Phi

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) and inflammatory breast cancer (IBC) are the most aggressive breast cancer subtypes. The tumor microenvironment (TME) is critical in driving these aggressive breast cancers' clinical phenotype and aggressiveness. Therefore, we explored novel actionable targets and complementary therapies targeting the TME to improve the outcomes of patients with these cancers.

In this thesis, we identified AXL as a potential therapeutic target in IBC due to its role in generating an immunosuppressive TME. Indeed, inhibiting the AXL pathway suppresses IBC tumor growth and reduces M2 macrophage populations in various mouse models. Mechanistically, AXL facilitates the polarization of M2 …

Impact Of Tumor Cell Expressed Cd38 On Metastasis And Immune Evasion In Breast Cancer, Tanvi Visal

Dissertations and Theses (Open Access)

Triple-negative breast cancer (TNBC) is a highly metastatic breast cancer subtype. The epithelial-to-mesenchymal transition (EMT) of cancer cells is a key feature of the metastatic cascade and is not a binary process but often generates malignant cells with both epithelial (E) and mesenchymal (M) traits known as hybrid EM cells. Recent studies highlight the enhanced metastatic potential of the hybrid EM cells. However, molecular insights and targetable vulnerabilities within hybrid EM remain elusive. We discovered that hybrid EM murine tumors are enriched in CD38, an immunesuppressive molecule associated with worse clinical outcomes in liquid malignancies but relatively understudied in solid …

Relationship Between Processing Body Formation, Epithelial-To-Mesenchymal Transition, And Invasion In Lung Adenocarcinoma, Amanda Warner

Dissertations and Theses (Open Access)

Lung cancer is the leading cause of cancer-related deaths in the United States, largely due to its ability to metastasize. Epithelial-to-mesenchymal transition (EMT) is a process that enhances the ability of cells to lose their cell-cell contacts, invade, and enter the blood stream which are essential during metastasis. Many transcriptional gene programs are altered during EMT such as activation of mesenchymal transcription factors, like ZEB1, and enhanced response to the TGFβ1 cytokine. In oncogenic contexts, TGFβ1 enhances the formation of processing-bodies (P-bodies) where P-body proteins are required for invasion in multiple cancerous cell lines. P-bodies are a type of ribonucleoprotein …

Rod Photoreceptor Regeneration In A Zebrafish Model With Retinitis Pigmentosa, Eyad Shihabeddin

Dissertations and Theses (Open Access)

A cellular hallmark of inherited retinal degenerative diseases is progressive loss of photoreceptors until one is completely blind. Unlike mammalian models, Zebrafish have the ability to naturally regenerate their neurons after injury or disease is detected. We have generated a zebrafish model with the most common autosomal dominant form of the inherited retinal degenerative disease known as Retinitis Pigmentosa. We utilize immunohistochemistry, single-cell RNA sequencing, several analysis tools, behavioral assays and oligonucleotides to characterize our zebrafish model and identify the transcription factors necessary for rod photoreceptor regeneration. We show that our zebrafish model has continuous degeneration and regeneration of rod …

Overcoming Resistance To Cdk4/6-Targeted Therapy Using Jak2/Stat3 Inhibitor In Triple-Negative Breast Cancer, Chuling Zhuang

Dissertations and Theses (Open Access)

Breast cancer is the most common type of cancer diagnosed in women, with nearly 30% of cases becoming metastatic accounting for over 90% of breast cancer-related deaths. Among different breast cancer subtypes, triple-negative breast cancer (TNBC) has the worst prognosis and the highest propensity to metastasize. However, TNBC patients have limited treatment options due to their lack of actionable drug targets while therapeutic resistances result in high rates of recurrence and metastasis. Cyclin-dependent kinase 4 and 6 (CDK4/6) are major cell cycle regulators that control G1 to S phase transition and aberrant hyperactivation of the CDK4/6 pathway results in uncontrolled …

Harnessing The Immunomodulatory Potential Of Radiofrequency Ablation To Improve Therapeutic Outcomes In Pancreatic Ductal Adenocarcinoma, Bhumi Maniyar

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) continues to rank among the most lethal cancers with poor prognosis. PDAC is characterized by a thick desmoplastic stroma, severe immunological suppression, and resistance tostandard treatments. The need for innovative therapeutic approaches is highlighted by the tumor microenvironment's (TME) critical role in promoting disease development and reducing the effectiveness oftreatment. A promising locoregional treatment that can induce tumor necrosis and modify the TME is endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA). However, there is still minimal understanding around its wider impact on stromal remodeling and immunological activation. This study investigates the immunomodulatory effects of RFA combined with neoadjuvant …

Role Of Mir-4732-3p In Breast Cancer Brain Metastasis And Brain Metastatic Tumor Microenvironment, Munazza Samar Khan

Dissertations and Theses (Open Access)

In this study, we aimed to identify microRNAs (miRNAs) that may play important roles in breast cancer brain metastasis (BCBM). To this end, we conducted miRNA-sequencing of extracellular vesicles isolated from the serum samples of 6 BCBM patients and 8 Stage I/II/III breast cancer patients, and identified 49 circulating miRNAs that were upregulated in BCBM patients compared to Stage I/II/III breast cancer. Upon further analysis, we identified miR-4732-3p to be upregulated in brain-tropic triple-negative breast cancer (TNBC) cell lines, compared to parental lines. MiR-4732-3p overexpression increased metastatic properties of TNBC cells, including proliferation, migration, invasion, and maintenance of a mesenchymal …

Uncovering A Fundamental Mechanism Underlying Female Oocyte Quality And Rasopathies Using C. Elegans As A Model System, Han Bit Baek

Dissertations and Theses (Open Access)

Signaling pathways are molecular networks that allow cells to communicate between and within themselves. They are crucial for the coordination of diverse cellular processes and are the molecular mechanism in which cells sense and respond to their environment. RAS (Rat Sarcoma) is a small GTPase that transmits extracellular growth factor signals through a downstream kinase cascade and ERK (Extracellular-signal regulated kinase) is the terminal kinase, and it controls cellular processes such as proliferation, differentiation, and survival by phosphorylating its downstream effectors. This post translational modification regulates the effector by modulating its activity, levels, and/or interaction with other molecules. Given the …

Exploring The Immunologic Consequences Of Atrx Deficiency In Glioma, Benjamin Whitfield

Dissertations and Theses (Open Access)

ATRX is a key chromatin regulator that is frequently mutated across multiple cancer types. One of the most common ATRX-mutated tumor types is the adult-type glioma, IDH-mutant, Astrocytoma. It is known that ATRX mutation leads to increases in DNA damage, replication stress, and global epigenetic regulation at a cell level; however, less is known about the impact of ATRX mutation on immune signaling. Furthermore, little is known about the interaction of ATRX loss with gain-of-function mutations in IDH. In this paper we set out to explore the impact of ATRX loss on immune signaling in gliomas, both in the context …

Stat3, Nf-Κb, And Estrogen Receptor Beta: The Balance Of Inflammation In K-Ras Mutant Lung Adenocarcinoma, Michael J. Clowers

Dissertations and Theses (Open Access)

K-ras mutant lung adenocarcinoma (KM-LUAD) is a difficult-to-treat cancer subtype in which chronic inflammation pervades the tumor immune microenvironment (TIME). Pro-inflammatory pathways dampen the response to treatments, including immune checkpoint inhibitors, necessitating therapies that target this inflammatory signaling network in the TIME. This network is underpinned by interaction and coordination of two inflammatory pathways: signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NF-κB). The balance of these transcription factors determines the degree of anti- vs. pro-tumor immunity, and a skewing towards STAT3 is known to promote tumor development and a pro-tumor TIME. It is also …

Wired For Degradation: How Post-Translational Control Of Inducible Camp Early Repressor Protein Influences Melanoma Fate, Melissa Rose Spigelman

Theses, Dissertations and Culminating Projects

Melanoma is a highly aggressive form of skin cancer frequently driven by mutations in the BRAF gene, particularly the BRAFⱽ⁶⁰⁰ᴱ variant, which leads to sustained activation of the MAPK signaling cascade. Recent studies implicate the cyclic AMP (cAMP) signaling axis in melanoma progression and therapeutic resistance, highlighting the role of the Inducible cAMP Early Repressor (ICER), a transcriptional antagonist of CREB and CREM. ICER is downregulated during melanomagenesis and subject to post-translational regulation via phosphorylation and ubiquitin-mediated degradation. To investigate ICER’s functional relevance in vivo, e utilized a zebrafish melanoma model harboring brafⱽ⁶⁰⁰ᴱ, tp53−/−, and mitf−/−mutations, in which mitf expression …

The Development Of Magmas Inhibition As A Potential Therapeutic Target In Temozolomide Resistant Glioma, Jennifer Duyen Tran

Electronic Theses, Projects, and Dissertations

Glioblastoma (GBM) is a highly aggressive brain tumor that remains a significant challenge in neuro-oncology today. Approximately 90% of GBM patients experience tumor recurrence within one to two years of diagnosis. Therefore, due to its high resistance to conventional therapies, new treatment strategies are urgently needed. The current standard of care for GBM is the chemotherapeutic Temozolomide (TMZ). TMZ is an oral alkylating agent, it functions by delivering a methyl group to purine bases. The development of resistance to TMZ is partially regulated by the DNA repair enzyme O6- methylguanine-DNA methyltransferase (MGMT). Despite the potential shown by MGMT promoter methylation …

Passive Electronic Cigarette Exposure Initiates Squamous Metaplasia In A Developing 3d Human Tracheobronchial Epithelial Tissue In-Vitro Model, Edgar Rolon

Electronic Theses, Projects, and Dissertations

The prevalence of vaping has rapidly increased. ECs are often perceived as less harmful than tobacco cigarettes. A recent meta-analysis showed electronic cigarette (EC) aerosols adversely affected the respiratory system, similar to cigarette smoke, with some effects specific to EC use. Failure to prevent these alterations could lead to life-long comorbidities, and predisposition to respiratory diseases, including COPD and squamous cell carcinoma. While these effects are the result of active vaping, EC aerosols can also settle on indoor surfaces, be absorbed passively through the skin or orally, enter the blood stream, and subsequently expose internal organs, including the airway basal …

Can A Ceh-27/Nkx2.1 Transgene Rescue Ceh-27 Neurodevelopmental Defects?, Meryl Gilmore, Martin L. Hudson

Symposium of Student Scholars

When the development of an organism’s nervous system is interrupted or altered, it can significantly impact that organism’s ability to survive and function properly. In our lab, we use a species of nematode called Caenorhabditis elegans as a model organism to characterize the roles of important transcription factors in human neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD). Utilizing C. elegans makes analyzing this process in a lab very easy for many reasons; they are very small, have a rapid life cycle, invariant cell lineage, transparent bodies, and most importantly, around 80% of their genes have human orthologs. In …

Degradation Of Vascular Networks In A Huvec Model Of Dm1, Bonnie E. Butler

Departmental Honors & Graduate Capstone Projects

Myotonic dystrophy type 1 (DM1) is a genetic disease that causes muscle wasting and affects multiple organ systems. DM1 is caused by expanded CTG repeats in the 3’ untranslated region of the dystrophia myotonica protein kinase (DMPK) gene (Harper, 2001). Skeletal muscle relies on capillaries for nutrient delivery and waste clearance (Olfert, 2016). Skeletal muscle and capillaries communicate via a variety of chemicals, including PDGF-BB which both skeletal muscle and endothelial cells secrete and have receptors for (Hamaguchi, 2023). Platelet derived growth factor receptor β (PDGFRβ), when bound to platelet derived growth factor BB (PDGF-BB), induces angiogenesis (Wang, 2012). In …

Bibliometric Analysis Of Research Trends Related To Human Immunodeficiency Virus., Madyson E. Johnson, Kaitlyn R. Coffman, Valerie Rivas, Elizabeth Barrett

ATU Scholars Symposium

Human immunodeficiency virus poses major health burden across the globe including the United States of America and has its zoonotic origin from the Simian Immunodeficiency viruses of sooty mangabey monkey and chimpanzee in Africa. Epidemiological trends indicate that even though the mortality rates for HIV are falling globally, the rates of new cases have been rising since 2010 in several countries including the USA. An estimated 0.5% of the human population is currently infected with the virus with countries like USA, India, Nigeria and South Africa carrying the highest burden of the disease. Host receptors such as CD4 and coreceptors …

Cloning The Yersinia Enterocolitica Alkaline Phosphatase For An Affinity Chromatography Ligand, Flavio E. Arellano

ATU Scholars Symposium

Alkaline phosphatase (ALP) is an enzyme responsible for the dephosphorylation of extra-cytoplasmic molecules. Conversion to a neutral molecule enhances their ability to pass through cell membranes. When microbes such as Yersinia enterocolitica are ingested, they are exposed to large changes in pH level. These changes range from ~pH6.5 in the oral cavity to pH 2 in the stomach and pH 8 in the mid-intestine. The ability of microorganisms to survive this change in pH it largely dependent on their ability to change which proteins are expressed at differing pH levels or their ability to modify those proteins to meet the …

Della Protein And Cbl-Cipk Signaling Pathway As Candidates For Genetic Engineering, Nathan F. Surles

ATU Scholars Symposium

No abstract provided.

The Effect Of Cellular Glucose Levels On Inotersen-Mediated Target Reduction In In Vitro Cell Models, Andrea Durwin

Honors Scholar Theses

Antisense oligonucleotide (ASO) drugs are a new therapeutic modality to treat rare as well as common diseases. These drugs work to reduce disease by targeting the mRNA of the gene that causes the disease, therefore limiting the proteins that further propagate the signs and symptoms of the disorder. Many people who suffer from more severe diseases, such as Alzheimer’s, Parkinson’s, Duchenne Muscular Dystrophy (DMD), and a wide array of cancers, utilize ASO drugs for treatment, but the drug is also used with those suffering from more common diseases such as diabetes. The efficacy of ASO drugs to silence their mRNA …

Mcf-7 Dense Breast Cancer Cells Modulate Stress Through Senescence, Lara Donadio, Moses Alfonso, Josiah Philip, Tyler Zatarain

Molloy Multidisciplinary Undergraduate Research Conference

Breast cancer remains a leading cause of cancer-related mortality among women worldwide, with dense breast tissue being recognized as a significant risk factor for its development. This dense breast tissue, characterized by a higher concentration of mammary glandular tissue, represents additional sites for tumor development. The following study explores how the MCF-7 immortal cell line, representing dense breast cancer, modulates stress responses through cellular senescence. Cellular senescence is a defense mechanism that halts the cell cycle and acts as a tumor suppression mechanism, preventing out-of-control cell proliferation triggered by cytological stress. To simulate these stress conditions, we applied two agents: …

Enhancing Skin Cancer Literacy Amongst Young Adults: A Digital Design, Katherine Stoll

Honors Projects

The skin plays a vital role in protection, regulation, and homeostasis of the human body. Skin cancer, despite being mostly preventable, is one of the most common cancers. Young adults, ages 18 to 25, are vulnerable targets due to risky behaviors and misinformation regarding skin cancer. This project was designed by using digital media and website design to enhance skin cancer health literacy among young adults. Using a systematic literature review and research methods, an interactive website was designed to improve skin cancer health literacy and eliminate common misconceptions. The topics addressed throughout the website were the biological factors of …

Embryonic Stem Cell Research, Huda Abu-Suwa, Lisa K. Lashley, Charles J. Golden

Essays in Developmental Psychology

Stem cell research is a controversial issue that has received considerable attention over the last three decades. Stem cell research began in the early 1980’s, when stem cells were obtained from mice embryos and utilized to understand the functioning of stem cells (Grivennikov, 2008). In 1998, researchers discovered techniques for obtaining embryonic stem cells from human and growing them in laboratories. Since them, substantial research has been conducted on stem cells and their potential uses, which includes increasing our understanding of diseases and how they occur, treating various diseases, and testing new medications for safety and efficacy (Taylor, 2005).

Investigating Genetic Regulators Of Crystal Cell Development In Drosophila Melanogaster, Andrea Feria, Nyla Walbrook, Anisa Turaeva, Rebecca Spokony

Publications and Research

Crystal cells, a subset of Drosophila melanogaster hemocytes, are important for melanization, a crucial immune response. While the genetic regulation of crystal cell develop remains incompletely understood, this study investigates the functions of five candidate genes: ACXB, ACXA, Gp210, CG4390, and Cyp4s3; identidied through previous genome-wide association studies. Using the Gal4/UAS system along with RNA interference (RNAi), we exclusively knocked down each gene in third instar larvae and quantified crystal cell populations following heat shock-induced melanization. Our results imply that the knockdown of ACXB and ACXA significantly increased crystal cell counts in both sexes, suggesting these genes either act as …

The Employment Of Apoptosis In Embryonic Development, Hannah R. Fioramonti

Senior Honors Theses

Programmed cell death is necessary for the elimination of excess or damaged cells in all stages of life, but this is especially true during embryonic and fetal development of mammals. Beginning before implantation and continuing until birth, both intrinsic and extrinsic apoptosis are employed within mammalian embryos to ensure the viability of the organism, proper organ morphogenesis, integrity of the genetic material, and the high quality of the germ line. The formation of both transient and permanent ectodermal, mesodermal, and endodermal structures often involves apoptosis. In this review, a selection of apoptotic events within each germ layer and occurrences of …

A Natural Short Sleep Mutation Promotes Longevity Through Mitochondrial Respiration In Drosophila, Pritika Pandey

LSU Doctoral Dissertations

Aging is an irreversible process characterized by progressive physiological decline and an increased risk of metabolic disorders, cognitive impairment, cardiovascular diseases, and neurodegeneration. Disruptions to the circadian clock—whether due to genetic mutations or behavioral factors—accelerate aging and age-related pathologies, highlighting a strong link between circadian regulation and longevity. However, certain individuals harbor a dec2^P384R mutation, which enables natural short sleep without the detrimental effects of chronic sleep deprivation. This suggests that these individuals have evolved adaptations that activate pro-health pathways, allowing them to function optimally with reduced sleep. To investigate the genetic mechanisms underlying these changes, we developed a …