Bachelor of Science, Walsh University, 2022, Honors

The way to cure a given illness is to understand the genetic components which contributed to its development within a given patient. Using the Xavier Method, a pie chart was created on Microsoft Excel which specified all the pathogenic proteins associated with Chronic Myeloid Leukemia (CML), including GATA-2, a transcriptional factor which upregulates cell proliferation while downregulating cell differentiation. Using the amino acid sequence of GATA-2 along with bioinformatic programs, the structure of the GATA-2 variant was developed and analyzed for conserved scores. This structural information revealed much about GATA-2's ability to bind to DNA, other transcriptional factors, and contribute to CML. It is hoped that other students will pick up from this research to investigate the other proteins associated with CML through a similar bioinformatics approach.

Committee: Thomas Freeland (Advisor); Jennifer Clevinger (Committee Co-Chair); Nina Rytwinski (Committee Co-Chair); Adam Underwood (Advisor) Subjects: Biochemistry; Bioinformatics; Computer Science; Oncology

PhD, University of Cincinnati, 2022, Medicine: Toxicology (Environmental Health)

The focus of this dissertation is Hepatocyte Growth Factor (HGF)/MET-mediated phosphorylation of STMN1 on Serine 16 and the impact on cell cycle progression and cell proliferation. While the treatment of low-grade prostate cancers (PCa) with androgen deprivation therapy (ADT) often eliminates androgen receptor (AR)+ bulk tumor cells, 20-30% of the men treated will eventually develop castration resistant prostate cancer (CRPC). Of note is that AR normally represses the transcription of the HGF receptor MET, and that prolonged therapy can downregulate AR expression, resulting in a corresponding increase in MET expression, reported to be an indicator of late stage PCa and poor overall survival. Progression to late stage PCa is also characterized by an increased production and secretion of HGF from cells within the tumor microenvironment (TME) to upregulate metastatic and proliferative cellular processes. In this dissertation, Chapter 1 provides context regarding the role of the TME in cancer development, progression, and therapeutic resistance; and a brief summary of the current understanding of HGF/MET signaling in cancer and its role in STMN1 phosphorylation. Chapter 2 presents novel findings regarding HGF/MET-mediated phosphorylation of STMN1 S16 and how this modulates cell cycle progression, proliferation and metastatic potential in both PCa cells and normal mouse mammary gland cells. Chapter 3 investigates how calcium/calmodulin-dependent protein kinase II (CAMKII) regulates PCa cell proliferation without triggering metastasis, and the role that the other three regulatory serines in STMN1 play in regulating PCa cell proliferation. Chapter 4 reports the role of constant degradation of AR by Mouse Double Minute 2 (MDM2) to maintain prostate cancer stem cell integrity. Chapter 5 provides an in-depth analysis of the advantages and challenges faced in our attempt to use CRISPR/Cas9 technology to generate stable iii mutant DU-145 cell lines expressing STMN1 sub (open full item for complete abstract)

Committee: Susan Kasper Ph.D. (Committee Member); Susan Waltz Ph.D. (Committee Member); Saulius Sumanas Ph.D. (Committee Member); Katherine Burns Ph.D. (Committee Member) Subjects: Cellular Biology

Doctor of Philosophy (Ph.D.), University of Dayton, 2022, Biology

Hippo pathway is an organ size regulating pathway that has implications in organogenesis, cell competition, compensatory proliferation, and regeneration. Previous studies have identified the role of impaired Hippo pathway in cancer and Alzheimer's. Down-regulation of pathway causes over proliferation by upregulation of target gene expression that promotes proliferation and prevents apoptosis. On the contrary, pathway hyper-activation causes cell death by upregulating a pro-apoptotic protein Hid and without affecting the expression of Diap-1, a target protein that prevents apoptosis. However, down-regulation of Hid fails to significantly rescue Hippo pathway mediated cell death. Work from a previous graduate student in our lab has shown that Hippo signaling regulates a key cell death gene dronc which is a homolog of the initiator caspase-9 in mammals. When Hippo levels are high, Yki is sequestered in the cytoplasm and dronc levels are high and cell death is the result. In contrast to that when Hippo is downregulated, Yki is free to move to the nucleus and cause changes in gene expression and dronc is also downregulated and the result is proliferation of cells. But the phenomenon between Yki and dronc are poorly studied. The aim of my work was to thus identify how Yki that interacts with Hippo pathway to regulate cell death via dronc regulation. Dronc is also a common target to the Ecdysone signaling which is an important steroid hormone in insects that allows spatio-temporal of gene expression to regulate events of cell death and growth during molting and metamorphosis. But the relationship between Hippo Signaling and Ecdysone signaling to regulate a common target such as dronc is underexplored. To attain this goal, we tested for genetic interaction between known Ecr pathway components and the Hippo pathway components to determine if there is any genetic epistasis between the components. Our experiments led to the identification of a feedback loop in which the downst (open full item for complete abstract)

Committee: Madhuri Kango-Singh (Advisor); Pitychoutis Pothitos (Committee Member); Andreas Bergmann (Committee Member); Amit Singh (Committee Member); Mark Nielsen (Committee Member) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 2021, Biomedical Sciences

Multiple sclerosis (MS) is a chronic inflammatory disease that affects the brain and spinal cord leading to demyelination. Symptoms in patients can present in a broad range. Mild symptoms may manifest as peripheral tingling or numbness, while severe symptoms may present as severe motor disabilities or sudden blindness. A number of disease modifying therapies are available to help improve quality of life, but there is presently no cure available. Per the current numbers, there are nearly 1 million adults in the US who suffer from MS. Proinflammatory T helper (Th) cells that infiltrate the central nervous system (CNS) are thought to be the initial mediators of disease. Findings from the mouse model of MS, experimental autoimmune encephalomyelitis (EAE) lead to the understanding that MS is an autoimmune disease where T cells are reactive to myelin antigens. Controlling the biology of these T cell responses could bring therapeutic benefits to patients. Previous work from our lab has helped establish the role of the type II arginine methyltransferase, PRMT5 (protein arginine methyltransferase 5) in Th cell expansion and EAE autoimmunity using selective inhibitors. However, the role and mechanism by which PRMT5 modulates T cell responses and EAE progression haven't been determined. During my time in the lab, we developed two conditional knockout mouse models to evaluate PRMT5's function in T cells. In my thesis work I used our mouse models, exploratory RNA sequencing (RNA-Seq) and mass spectrometry techniques to uncover the mechanisms of action that drive T cell differentiation, expansion and the PRMT5 mediated symmetric dimethylation (SDM) targets of T cells. We identified a link between PRMT5 and cholesterol metabolism in Th17 cell development. We found that cholesterol pathway intermediates act as agonists for ROR-γt, the signature transcription factor encoding Th17 cells. PRMT5 expression was necessary for proper activity of the enzymes driving cholester (open full item for complete abstract)

Committee: Mireia Guerau-de-Arellano (Advisor); Stephen Kolb (Committee Member); Federica Accornero (Committee Member); Robert Baiocchi (Committee Member) Subjects: Biomedical Research; Immunology

Master of Science, Miami University, 2020, Chemical, Paper and Biomedical Engineering

As the population of the world ages, the field of tissue engineering is becoming increasingly important due to the need for replacement or regeneration of damaged tissues. One proposed solution to this issue is the use of 3D tissue scaffolds to guide cell growth in damaged tissues. A variety of methods have been used to manufacture scaffolds for this purpose, including 3D Bioplotting (3DP) and thermally induced phase separation (TIPS). Both techniques offer opportunities to finely tune the pore size, connectivity, density, and size of the resulting scaffolds. This work describes a hybrid 3DP/TIPS technique used to fabricate highly porous scaffolds made of poly(lactic-co-glycolide) (PLGA) and nano-hydroxyapatite (nHA). The effects of varying compositions of PLGA and nHA were examined on the porosity and mechanical characteristics of the scaffolds. MC3T3-E1 preosteoblast cells were used in both in vitro tests and perfusion bioreactors to assess cell proliferation and differentiation in static and dynamic cell culture environments. CellCeramTM scaffolds were obtained from Sigma Aldrich and subjected to the same cell culture conditions. Flow through the scaffold geometry in a perfusion bioreactor was investigated and modeled in COMSOL. Cell proliferation and differentiation on the scaffolds were then assessed and compared.

Committee: Azizeh Yousefi Moshirabad (Advisor); Paul F James (Advisor); Justin M Saul (Committee Member) Subjects: Biomedical Engineering; Chemical Engineering

Doctor of Philosophy (PhD), Wright State University, 2020, Biomedical Sciences PhD

ΔNp63α is a p53 transcription factor family member that promotes cellular proliferation and survival. In squamous cell carcinoma (SCC), ΔNp63α overexpression is associated with poor prognosis and survival, implicating it as a proto-oncogene. Despite its importance in SCC, the mechanisms regulating ΔNp63α expression are poorly understood. We have identified the acetyltransferase TIP60 as a novel upstream regulator of ΔNp63α levels. We discovered that TIP60 regulates ΔNp63α via two mechanisms. First, TIP60 upregulates ΔNp63α mRNA levels. Moreover, pharmacological inhibition of TIP60 activity reduces ΔNp63α transcript levels, indicating that TIP60-cataltyic activity is vital to amplified transcription of ΔNp63α. Second, we have demonstrated that TIP60 promotes ΔNp63α protein stability by preventing its ubiquitination and proteasomal degradation. This study further shows that TIP60 co-localizes with, interacts with, and directly acetylates ΔNp63α. Utilizing mass spectrometry and site directed mutagenesis, we found that TIP60 acetylates ΔNp63α residues K138, K139, and K494, respectively. We additionally revealed that preventing acetylation of these sites inhibit TIP60-mediated stabilization of ΔNp63α, providing evidence that acetylation by TIP60 enhances ΔNp63α protein stability. We further investigated the functions of the TIP60-ΔNp63α axis in the regulation of SCC proliferation. We discovered that regulation of ΔNp63α by TIP60 increases cellular proliferation. In accordance with the functional role of ΔNp63α, pharmacological inhibition of TIP60 reduced SCC cell proliferation suggesting TIP60 may have therapeutic potential in cancers exhibiting ΔNp63α overexpression. Furthermore, we investigated the mechanisms by which TIP60 regulation of ΔNp63α enhances cancer cell proliferation. We discovered that TIP60 upregulation of ΔNp63α represses p21Cip1/Waf1 levels, resulting in increased G2/M progression. In conclusion, this study uncovers a novel mechanism promoting ΔNp (open full item for complete abstract)

Committee: Madhavi Kadakia Ph.D. (Advisor); Thomas L. Brown Ph.D. (Committee Chair); Paula A. Bubulya Ph.D. (Committee Member); Weiwen Long Ph.D. (Committee Member); Michael P. Markey Ph.D. (Committee Member) Subjects: Biochemistry; Biomedical Research; Cellular Biology; Molecular Biology; Oncology

Doctor of Philosophy, The Ohio State University, 2015, Molecular Genetics

Robust mechanisms to control cell proliferation have evolved to maintain the integrity of organ architecture and tissue homeostasis. Disruption of these mechanisms, either intracellular circuits or extracellular inputs for cell proliferation control, inevitably occur under oncogenic conditions, rendering cells with unlimited proliferative capacity and subsequent malignant transformation. Here, we investigated how two critical intracellular proliferative pathways, Myc and E2f, are integrated to control cell cycle transitions in normal and Rb deficient cells using a murine intestinal model. We show that in contrast to the current paradigm, Myc and E2f1-3 have little impact on normal G1-S transitions. Instead Myc and E2f1-3 synergistically control an S-G2 transcriptional program in intestinal crypts required for completing normal cell divisions and maintaining crypt-villi integrity. Surprisingly, Rb deficiency results in the Myc-dependent accumulation of E2f3a protein and the genome-wide repositioning of Myc and E2f3 on chromatin associated with `super activation' of a G1-S transcriptional program, ectopic S phase entry and rampant cell proliferation. These findings reveal that Rb deficient cells hijack and redeploy Myc and E2f3 from an S-G2 program essential for normal cell cycles to a G1-S program that re-engages ectopic cell cycles, exposing an unanticipated addiction of Rb-null `cancer-like cells' on Myc. We have also studied how cell non-autonomous inputs derived from stromal compartment in the tumor microenvironment impacts the proliferation of tumor compartment. We performed a genome-wide stroma-specific RNAi screen in `cancer sensitized' C. elegans and discovered 39 stromal factors that suppress the proliferation of adjacent `Ras pathway-sensitized' epithelial cells, with minimal impact on the proliferation of normal or `Wnt pathway-sensitized' epithelial cells. These candidate genes encode histone variants and components of protein complexes known to conv (open full item for complete abstract)

Committee: Gustavo Leone (Advisor); Helen Chamberlin (Committee Member); Harold Fisk (Committee Member); Tsonwin Hai (Committee Member) Subjects: Biomedical Research; Cellular Biology; Genetics

Doctor of Philosophy, Case Western Reserve University, 2015, Biomedical Engineering

Existing imaging modalities for tracking cells in vivo have many limitations such as limited resolution or limited field of view. Cryo-imaging is the only imaging technology that enables cell tracking with single cell sensitivity throughout entire animals in small rodents. It provides cell detection anywhere in mice and determines cell densities far below that which can be observed with any other imaging technologies such as MRI, CT, PET, SPECT and BLI. Using the novel imaging and detection technologies, we explored therapeutic mechanisms of mesenchymal stem cell (MSC) in murine models of graft-versus-host disease (GVHD). Many investigators have found that intravascular infusion of exogenous MSCs improves outcomes of GVHD-induced animals. Although, at least 40 clinical trials are in progress, it is still unclear what the therapeutic mechanism is? In this study, the proposed working hypothesis is that the MSCs specifically go to secondary lymphoid organs (SLOs) in order to suppress alloreactive T-cells proliferation which eventually leads to the attenuation of GVHD. In this study, we show that the hypothesis is indeed the mechanism behind the scene and is testable using our proposed imaging technology and experiments. Firstly, we extended/optimized cryo-imaging technology to detect/analyze/visualize of fluorescently labeled cells (MSCs and T-cells). Secondly, we identified bio-distribution of MSCs in a GVHD mouse model. We found evidence showing that MSCs preferentially co-localize with the effector T-cells in the SLOs after intravenous infusion. Lastly, we observed that MSCs could suppress T-cells proliferation in vivo. Novel T-cell proliferation assays were established to study the effectiveness of the MSC therapy. The assays were developed based on SLO volume enlargement approach and CFSE dilution approach. This project is significant as we have developed a new, important technique for the study of stem cell bio-distribution with single cell sensitivity o (open full item for complete abstract)

Committee: David Wilson PhD (Committee Chair); Kenneth Cooke MD (Committee Member); Andrew Rollins PhD (Committee Member); Vira Chankong PhD (Committee Member); Wouter van't Hof PhD (Committee Member) Subjects: Biomedical Engineering; Biomedical Research; Computer Science; Experiments; Immunology; Medical Imaging

Doctor of Philosophy, Case Western Reserve University, 2014, Biomedical Engineering

The key role of smooth muscle cell (SMC) migration and proliferation in vascular physiological and pathological remodeling necessitates the exploration of mechanisms underlying these functions. This work focuses on engineering a poly (ethylene glycol) (PEG) hydrogel as a model system to evaluate SMC migration and proliferation in three dimensions (3D). We hypothesized that 3D SMC migration and proliferation can be regulated by the properties of a cell-instructive scaffold, including cell-matrix adhesion, degradability, and cross-linking density. To accomplish this, bio-inert PEG-based hydrogels were designed as the scaffold substrate. To mimic the properties of the extracellular matrix (ECM), cell-adhesive peptide (GRGDSP) and enzyme-sensitive peptide (VPMSMRGG or GPQGIAGQ) were incorporated into the PEG macromer chain. Copolymerization of the biomimetic macromers by photopolymerization resulted in the formation of bioactive hydrogels with the dual properties of cell adhesion and proteolytic degradation. Studies of mass swelling ratio as a function of gel compositions indicated that this hydrogel can be engineered quantitatively to allow for uncoupled investigation of scaffold properties on cell functions. By utilizing these biomimetic scaffolds, we studied the effect of adhesive ligand concentration, proteolysis, and network cross-linking density on 3D SMC migration and proliferation. Our results indicated that 3D SMC migration and proliferation were critically dependent on cell-matrix adhesiveness, proteolysis, and cross-linking density. The incorporation of cell-adhesive ligand significantly enhanced SMC spreading, migration and proliferation, with cell-adhesive ligand concentration mediating 3D SMC migration and proliferation in a biphasic manner. The faster degrading hydrogels promoted SMC migration and proliferation. In particular, higher cross-linking density could impede 3D SMC migration and proliferation despite the presence of cell-adhesive ligands and pro (open full item for complete abstract)

Committee: Kandice Kottke-Marchant (Committee Chair); Anirban Sen Gupta (Committee Member); Horst von Recum (Committee Member); Stuart Rowan (Committee Member) Subjects: Biomedical Engineering; Polymers

MS, University of Cincinnati, 2012, Medicine: Molecular and Developmental Biology

SAM Pointed Domain Containing ETS Transcription Factor (SPDEF) is a new member of ETS transcription factor family that is originally discovered in the epithelium of prostate. Like other ETS family members, SPDEF is involved in multiple biological processes including cell fate determination and specification, cell proliferation, epithelial-to-mesenchymal transformation and migration. Although much work has been done to elucidate the role of SPDEF in normal physiological conditions and in cancers, its expression level in cancer is still controversial. Similarly, there is no conclusive message on the role of SPDEF in cancer despite the fact that several in vitro studies have been done. We first overviewed the discovery and properties of SPDEF, followed by a comprehensive review of the role of SPDEF, with a special focus on its role in the development of cancer. In the second chapter, we utilized a xenograft model to manipulate SPDEF level in mouse prostate cancer. After orthotopic injection, we found that overexpression of SPDEF resulted in smaller tumors in mice. We also showed that several target genes related to cell proliferation and migration are down-regulated by SPDEF overexpression. We confirmed down-regulation of these genes in prostate cancer cell lines. In fact, we found that SPDEF overexpression inhibited cell migration, resulting in reduced aggressiveness of tumor cells. In addition, SPDEF overexpression was shown to suppress tumor growth via alteration of cell cycle profile. Collectively, these data indicate that SPDEF suppresses tumor growth via inhibition of cell proliferation and migration.

Committee: Tanya Kalin PhD (Committee Chair); Vladimir Kalinichenko MD PhD (Committee Member); Jeffrey Whitsett MD (Committee Member) Subjects: Molecular Biology

Master of Science, The Ohio State University, 2011, Veterinary Clinical Sciences

Gemcitabine has demonstrated synergistic antitumor activity in a variety of human cancer cells when combined with carboplatin. The purpose of this study was to evaluate the antitumor activity of gemcitabine in canine TCC cell lines alone and in combination with carboplatin. We hypothesized that combined gemcitabine and carboplatin would have synergistic effects in vitro in canine TCC. Demonstration of synergistic antitumor activity in canine TCC cell lines would provide a rationale for effective treatment of canine TCC with this combination of drugs. Five TCC cell lines were treated with gemcitabine, carboplatin, and the combination. Cell proliferation was assessed using CyQUANT® cell proliferation assay, cell cycle was evaluated using propidium iodide staining, and apoptosis was assessed by measuring caspase-3/7 enzymatic activity. Synergy was quantified by combination index analysis using CompuSyn software. Treatment of canine TCC cell lines with carboplatin or gemcitabine decreased cell proliferation, increased apoptosis, and induced cell cycle arrest. When TCC cell lines were treated with gemcitabine and carboplatin in combination at therapeutically relevant concentrations, a significant decrease in cell proliferation was observed compared to gemcitabine or carboplatin alone and the drug combination was synergistic in 3 of 5 cell lines and additive in the other two. Drug sequence did not reliably affect cell proliferation amongst cell lines during combination treatment. We conclude, gemcitabine exhibits biologic activity against canine TCC cells and when combined with carboplatin the two exhibit synergistic activity. Our results support further evaluation of this drug combination in dogs with TCC to determine its clinical efficacy.

Committee: Nongnuch Inpanbutr DVM, PhD (Advisor); William Kisseberth DVM, PhD (Advisor); Dennis Chew DVM (Committee Member) Subjects: Veterinary Services

Master of Science, The Ohio State University, 2006, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2024, Vision Science

Purpose: The mechanisms underlying optic cup and lens epithelial cell proliferation remain unknown. Previous studies have shown that biomechanical strain elicits a proliferative response in epithelial cells. Shroom3, a cytoskeletal protein, is necessary for ocular development and facilitates lens placode invagination. Preliminary studies demonstrate that Shroom3 mutants lack ventral optic cup closure, illustrating the significance of Shroom3 in epithelial folding, fusion, and potentially, proliferation. We hypothesize that inducing intercellular stress through Shroom3 overexpression increases proliferation in vitro, and Shroom3 deficient mice show a decrease in proliferation in the optic cup. Methods: Model epithelia, Madin-Darby canine kidney (MDCK) cells, were transfected with Shroom3 to create a stable line (pTre3G-Shroom3-mCherry), inducible with doxycycline with dual selection hygromycin/G418. Once cells reached confluence, EdU was incorporated and cells were imaged in multiple locations (n=5) using Zeiss Axio Observer (N=3). Control experiments were performed using MDCK wildtype cells to test whether doxycycline affects proliferation. The number of nuclei and EdU+ cells were counted using ImageJ. Shroom3 mutant mice at E10.5 were utilized to assess apical cell area in the optic cup, and Shroom3 deficient mice at E12.5 were stained for the proliferation marker phospho-histone 3 (pH3), and imaged (n= 7 ; N=2). Statistical analysis was performed using unpaired t-test and Mann Whitney U test. Results: Shroom3 overexpression in MDCK cells resulted in significantly reduced mitosis, as shown through the percentage of EdU+ cells (p≤0.001). The addition of doxycycline affected proliferation differently depending on the location of cells on the coverslip. Peripheral doxycycline+ wildtype (wt) cells showed decreased proliferation compared to pTre3G-Shroom3-mCherry doxycycline- cells, but not compared to peripheral doxycycline- wt cells. Central doxycycline+ wt cells sh (open full item for complete abstract)

Committee: Heather Chandler (Advisor); Timothy Plageman (Advisor); Andrew Hartwick (Committee Member); Phillip Yuhas (Committee Member) Subjects: Cellular Biology; Ophthalmology

PhD, University of Cincinnati, 2022, Medicine: Molecular and Developmental Biology

Heart failure causes millions of deaths annually and presents a large global healthcare burden. A regenerative cure for the damaged myocardium, where new muscle forms by proliferation of pre-existing cardiomyocytes, is an attractive therapeutic goal. Adult mammalian cardiomyocytes are terminally-differentiated, only capable of proliferating at a very low rate that is insufficient for a regenerative response after myocardial infarction. However, over the past decade, a transient innate capacity for cardiac regeneration during the early neonatal period has been described in both rodents and swine. Whether such a capacity exists in newborn human infants is unknown. Studying the mechanisms of regenerative potential in neonatal rodents and swine could offer greater insight into heart development in human neonates, and also facilitate discovery of novel targets for human heart disease therapy. Cardiomyocyte maturational processes occur concurrent with loss of heart regenerative potential in early neonatal mice. These maturational processes, and the transcriptional mechanisms regulating them, have been successfully manipulated to induce cardiac regenerative repair in adult mouse hearts after injury. Pigs also possess a similar period of early neonatal heart regenerative capacity as mice. However, the maturational dynamics of cardiomyocyte growth in the postnatal pig heart are not well-defined, despite popularity of swine as large mammal models for cardiac preclinical studies. In Chapter 2 of this dissertation, we describe cardiac maturation in postnatal swine from newborn to adolescent ages. Our results show discordance between time of terminal cardiomyocyte maturation and loss of heart regenerative potential in postnatal swine, dissimilar to rodents. Further, postnatal pig cardiomyocytes are distinct from rodents and humans, exhibiting extensive multinucleation of up to 16 nuclei per cardiomyocyte by 6 postnatal months. These differences hold importance for preclin (open full item for complete abstract)

Committee: Katherine Yutzey Ph.D. (Committee Member); Stacey Huppert Ph.D. (Committee Member); Joshua Waxman Ph.D. (Committee Member); Sakthivel Sadayappan Ph.D. (Committee Member); Nancy Ratner Ph.D. (Committee Member) Subjects: Developmental Biology

Doctor of Philosophy (PhD), Wright State University, 2022, Biomedical Sciences PhD

Breast cancer is the most prevalent cancer in women. Approximately 75% of breast cancers are estrogen receptor alpha positive (ER+) and are treatable with endocrine therapies and/or CDK inhibitors. However, endocrine therapy (ET) resistance and metastasis are major obstacles in advanced ERα+ breast cancer (ER+ BCa) therapeutics. Upregulated oncogenic ERα activity plays critical role in progression of ER+ BCa. One essential mechanism of regulating ERα signaling is the ubiquitination-dependent proteasomal degradation of ERα. Owing to its direct effect on ERα degradation, fulvestrant is a first-line FDA-approved ET for metastatic and locally advanced breast cancer and a second-line drug for treatment of unresponsive ER+ BCa progression. Unfortunately, intrinsic or acquired resistance to fulvestrant develops in majority of patients with advanced ER+ BCa. The mechanism underlying fulvestrant resistance is still largely unknown. In the current study, we have identified F-Box and Leucine-Rich Repeat Protein 16 (FBXL16) as a novel positive regulator of oncogenic ERα signaling. F-box proteins are major components of the SCF (SKP1-CUL1-F-box) E3 ubiquitin ligases that mediate protein ubiquitination. FBXL16 does not show detectable interaction with CUL1 and is a poorly studied F-box protein. Our lab has recently discovered that FBXL16 upregulates several oncoproteins targeted by SCF-E3 ligases, including c-myc and β-catenin. However, little is known about the roles of FBXL16 in cancer. By data-mining of cancer-related databases and immunohistological analysis of BCa tissue microarrays, we found that FBXL16 is highly upregulated in invasive ductal and lobular carcinomas. There is a strong positive correlation between FBXL16 expression and ERα status, implying its important role in ER+ BCa. Our study reveals that FBXL16 stabilizes ERα and decreases ERα ubiquitination thereby promoting ERα-mediated transcription and breast cancer cell proliferation. Specifically, we identified th (open full item for complete abstract)

Committee: Weiwen Long Ph.D. (Advisor); Madhavi Kadakia Ph.D. (Committee Member); David R. Ladle Ph.D. (Committee Member); Hongmei Ren Ph.D. (Committee Member); Shulin Ju Ph.D. (Committee Member) Subjects: Biomedical Research; Molecular Biology

Doctor of Philosophy, Case Western Reserve University, 2020, Molecular Medicine

Objective: Prostate cancer is the second leading cause of cancer-related deaths among men in the US. Although some reports show high concentrations of HDL cholesterol increase risk for prostate cancer, this association has not been consistent. High density lipoprotein (HDL) metabolism, is facilitated largely by scavenger receptor class B, type 1 (SR-B1) that mediates its uptake into cells, and ABCA1 that mediates its generation. SR-B1 is upregulated in prostate cancer tissue, whereas some evidence suggests that ABCA1 is downregulated in the disease. Our efforts were to determine if SR-B1-dependent HDL uptake and/or HDL biogenesis by ABCA1 export of lipids to apoA1 promotes prostate cancer cell proliferation and disease progression. Hypothesis: HDL uptake by SR-B1 drives prostate cancer proliferation and disease progression, whereas ABCA1 mediated lipid efflux decreases prostate cancer proliferation and disease progression (Fig. Abstract) Methods and Results: Here, we report that knockout (KO) of SR-B1 via CRISPR/Cas9 editing led to reduced HDL uptake into prostate cancer cells, and reduced their proliferation in response to HDL. In vivo studies using syngeneic SR-B1 wildtype (SRB1+/+) and SR-B1 KO (SR-B1-/-) prostate cancer cells in WT and apolipoprotein-AI KO (apoA1-KO) C57BL/6J mice showed that WT hosts, containing higher levels of total and HDL-cholesterol, grew larger tumors than apoA1-KO hosts with lower levels of total and HDL-cholesterol. Furthermore, SR-B1-/- prostate cancer cells formed smaller tumors in WT hosts, than SR-B1+/+ cells in same host model. Tumor volume data was overall consistent survival data. Conclusion: The results suggest that HDL through tumoral SR-B1 significantly influences the proliferation of prostate cancer cells and is a driver of the disease. Further investigation is needed to conclusively determine how HDL metabolism by ABCA1 influences prostate cancer cells and its impact on disease progression.

Committee: Jonathan Smith PhD (Advisor); Angela Ting PhD (Committee Chair); W.H. Wilson Tang MD (Committee Member); J. Mark Brown PhD (Committee Member); Nima Sharifi MD (Committee Member) Subjects: Cellular Biology; Medicine; Molecular Biology; Oncology

Bachelor of Science, Marietta College, 2018, Chemistry

Propofol (2,6-diisopropylphenol) is a commonly utilized general anesthetic that has been shown to induce apoptosis. Propofol derivatives of varying lipophilicity were used to treat H-1299 human lung cancer cells. Lipophilicity is a significant characteristic that effects whether a compound can enter a cell by passing through the membrane. Clonogenic assays were used to evaluate the effect of each of the compounds on the number of cells attached to the plate after a 24-hour incubation. Dose-response curves were created for phenol, 2,6-dimethylphenol, propofol, and 2,6-di-t-butylphenol. Trend lines for the linear portion of the data were used to estimate LC20 values. The LC20 values for the compounds tested were compared, and no definitive trend was found relating lipophilicity to the number of living cells remaining on the plate after treatment. This could be a result of cell death being secondary to the anesthetic action of propofol. The calculated LC20 values were: 206 micromolar for phenol, 16.3 micromolar for 2,6-dimethylphenol, 9.33 micromolar for propofol, and 101 micromolar for 2,6-di-t-butylphenol. ANOVA testing found statistical significance between the various concentrations tested for phenol and propofol.

Committee: Kimberly Parsons (Advisor); David Brown (Committee Member) Subjects: Biochemistry; Chemistry

Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee: Not Provided (Other) Subjects: Health Sciences

Doctor of Philosophy, The Ohio State University, 1982, Graduate School

Committee: Not Provided (Other) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 1980, Graduate School

Committee: Not Provided (Other) Subjects: Chemistry