MS, University of Cincinnati, 2024, Medicine: Cancer and Cell Biology

The development and growth of cancer is fundamentally dependent on pro-tumor changes in metabolism. Cancer cells generally shift away from oxidative phosphorylation as the primary source of energy and rely more heavily on glycolysis. Receptor tyrosine kinases (RTKs) are a type of receptor that is implicated in this shift to pro-tumor metabolism. RTKs are important drivers of cancer growth and metastasis. One such family of RTKs is the MET family, which consists of MET and RON(MST1R). The overexpression of either MET or RON has been associated with worse cancer patient prognosis in a variety of tumor types. Both MET and RON signaling promote increased glycolysis by upregulating the expression of key glycolytic enzymes via increased MYC transcription factor activity. Additionally, both MET and RON signaling promote increased cholesterol biosynthesis downstream of glycolysis by upregulating the expression of SREBP2-induced cholesterol biosynthesis enzymes via CTTNB1. These changes in metabolism, driven by RTK activity, provide potential targets in limiting tumor growth and metastasis via pharmacological inhibition or modifications in diet. This review summarizes pro-tumor changes in metabolism driven by the MET family of RTKs. In doing so, we will offer our unique perspective on metabolic pathways that drive worse patient prognosis and provide suggestions for future study.

Committee: Susan Waltz Ph.D. (Committee Chair); Susanne Wells Ph.D. (Committee Member); Amanda Wasylishen Ph.D. (Committee Member) Subjects: Cellular Biology

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 (PhD), Ohio University, 2020, Molecular and Cellular Biology (Arts and Sciences)

Breast cancer cells (BCCs) potentiate hematogenous metastasis by expressing specialized glycosylated proteins and lipids that act as ligands to E-selectin, a cell adhesion molecule expressed on cytokine-activated endothelial cells that line blood vessel walls, under hemodynamic shear stresses. Recently, the functional E-selectin ligand activities of BCCs were shown to be modulated by Snail and Twist transcription factors (TFs) that regulate the epithelial-to-mesenchymal transition (EMT) and the mesenchymal-to-epithelial transition (MET), key processes in metastasis. However, the influence on the functional E-selectin ligand activities of BCCs by physiologically important molecules reported to initiate EMT or MET signaling cascades has yet to be determined. Consequently, the potential for microRNA-200c (miR-200c), an miR overexpressed in the blood of metastatic BC patients, to modify the functional E-selectin ligand activities of BCCs via the MET was determined. Transient overexpression of miR-200c in MDA-MB-231 BCCs induced the MET and flow cytometry analysis revealed that the expression of binding epitopes recognized by E-selectin was significantly higher in these cells compared to cells treated with a negative control miR. Furthermore, cells overexpressing miR-200c had higher functional E-selectin ligand activities, as these cells had significantly lower rolling velocities on E-selectin, significantly higher levels of firm adhesion to E-selectin, and significantly lower detachment from E-selectin in shear flow adhesion assays. Consistent with these findings, gene expression of fucosyltransferase 3 (FUT3) and FUT6, the primary enzymes responsible for the synthesis of functional E-selectin ligands on epithelial BCCs, was significantly higher in cells following miR-200c-induced MET. MiR-200c-induced MET is caused by Zeb1 and Zeb2 TFs, suggesting a novel pathway by which the MET regulates the functional E-selectin ligand activities of BCCs. Over-activation of Notch si (open full item for complete abstract)

Committee: Monica Burdick (Advisor); Douglas Goetz (Committee Member); Fabian Benencia (Committee Member); Amir Farnoud (Committee Member) Subjects: Bioinformatics; Cellular Biology; Molecular Biology

Master of Sciences, Case Western Reserve University, 2019, Biology

Mechanotransduction is vital for the senses of hearing and balance. Mechanotransduction occurs when a physical stimulus causes mechanically-gated channels of a sensory cell to open, allowing ions to enter the cell, thus converting a mechanical signal into an electrical one. We know that the mechanoelectrical transduction (MET) channel of sensory hair cells of the inner ear is located at the tips of actin-based stereocilia, but the identity of the pore-forming protein of the channel is unknown. It is also uncertain whether the proteins composing the channel are constant, or if they vary between hair cells based on differences in physiological requirements. In this thesis, I measure stimulus-evoked microphonic potentials of zebrafish hair cells to first determine the electrophysiological response amplitude of wildtype lateral line neuromasts, and then I use this method to examine how the mutation of certain hair cell genes affects mechanotransduction of the lateral line and inner ear. I find evidence to suggest that the MET channel components vary between hair cells, and that the proteins at the pore of the channel differ between mammals and zebrafish. This information may allow us to better understand hair cell tuning at the level of the MET complex and how the proteins necessary for mechanotransduction vary among vertebrates.

Committee: Brian McDermott (Advisor); Susan Burden-Gulley (Committee Member); Hillel Chiel (Committee Member); Ruben Stepanyan (Committee Member); Nicole Crown (Committee Chair) Subjects: Biology; Neurobiology; Neurosciences

Master of Science (MS), Ohio University, 2017, Biomedical Engineering (Engineering and Technology)

The role mechanical properties play in the interconnected network of cellular control mechanisms is becoming better understood. Specifically, mechanical stiffness has been shown to be a marker capable of distinguishing between malignant and benign cancer phenotypes. Traditional techniques to measure cell stiffness share the commonality of low throughput. Microfluidic technology has been used to attain stiffness related data at a high throughput, however data collection and analysis is almost exclusively reliant on video spectroscopy. Through the use of a serial multi-constriction microfluidic device, cell ease of transit, i.e., agility, can be measured by the transit through the serial network developed herein. This measure of agility has the capability to differentiate cells based on phenotype, specifically phenotypes characteristic of the epithelial-to-mesenchymal transition, EMT, which occurs in cancer cells upon initiation of metastasis. By developing a compatible microfluidic sensor, the post processing of cell agility data has the potential to be automated and moved toward a non-video spectroscopy dependent system. These improvements push the technology of cellular mechanical property data analysis toward a faster, more convenient platform, thus allowing a better understanding of how mechanical properties correspond with biological behavior of mammalian cells.

Committee: Monica Burdick Dr. (Advisor); Robert Williams Dr. (Committee Member); Douglas Goetz Dr. (Committee Member); Allan Showalter Dr. (Committee Member) Subjects: Biomechanics; Biomedical Engineering

Master of Sciences, Case Western Reserve University, 2014, EMC - Mechanical Engineering

Cleveland wind and ice conditions in Lake Erie were assessed at the City of Cleveland's water intake crib. The area was found to have an average wind speed of 7.37 m/s (15.5 mph) at 50 m (164 ft) with a mean turbulence intensity of 0.07. Wind shear was found to be 0.09 as compared to the recommended value of 0.11 by the IEC. Prevailing winds entered from the southwest on average but seasonal variation was present. Extreme 10 minute wind speeds across 1 year and 50 years were 25.33 m/s (56.66 mph) and 36.86 m/s (82.45 mph) respectively. Ice measurements recorded using a shallow water ice profiling system found ice present in at depths up to 9.0 m (29.5 ft) in 2011. Ice simulation using a freshwater lake ice model and data from 2008 through 2013 found a maximum level ice of 0.55 m (1.82 ft) on February 13, 2011.

Committee: David Matthiesen PhD (Committee Chair); Jaikrishnan Kadambi PhD (Committee Member); Paul Barnhart PhD (Committee Member) Subjects: Atmospheric Sciences; Mechanical Engineering

PhD, University of Cincinnati, 2012, Education, Criminal Justice, and Human Services: Criminal Justice

Over the last several decades, groundbreaking advances have occurred across multiple fields of human sciences. These advances have had the largest effect in the medical field. Current understanding of human development over the life course is more comprehensive, and even more complex. These advances have also nudged the field of criminology toward a more complete model to explain individual behavior, including the influences of early life problems and their effects on behavior. To this end, this research examines factors contributing to behavioral problems early in life, which may assist in the development of antisocial behavior. Utilizing a meta-analytic approach, a synthesis of current perceptions of inducers to antisocial behavior is analyzed. Specifically, this dissertation examines the role of prenatal effects, birth complications, and other early life trauma, onto problematic behavior and aggression. Implications for inclusion of these important times in the life course into theoretical discussion are presented.

Committee: John Wright PhD (Committee Chair); Melissa M. Moon PhD (Committee Member); Edward Latessa PhD (Committee Member); Paula Smith PhD (Committee Member) Subjects: Criminology

Doctor of Philosophy, The Ohio State University, 2011, Comparative and Veterinary Medicine

Osteosarcoma (OSA) is the most common malignant bone tumor in children and dogs. Currently, 30-40% of children and greater than 90% of dogs succumb to the disease following treatment. The receptor tyrosine kinase (RTK) Met has emerged as a potential target for therapeutic intervention for OSA. Met overexpression in human OSA is associated with a more aggressive phenotype and poor survival, and aberrant expression in normal human osteoblasts induces malignant transformation. The purpose of this work was to evaluate Met as a target for therapeutic intervention in OSA. The first objective was to determine if Met interacts with heat shock protein 90 (Hsp90) in OSA and evaluate a novel Hsp90 inhibitor, STA-1474, for OSA treatment. Hsp90 associated with co-chaperones in canine OSA cells but not normal canine osteoblasts, indicating formation of an active superchaperone complex in malignant versus normal tissue. STA-1474 promoted loss of cell proliferation, apoptosis, and induction of Hsp70. STA-1474 treatment also resulted in the down-regulation of HGF (hepatocyte growth factor) induced p-Met/Met, p-STAT3, and p-Akt/Akt. These data suggest that STA-1474 may be useful for the treatment of OSA. The second objective was to determine whether RTKs Met, epidermal growth factor receptor (EGFR), and Recepteur d'origine nantais (Ron) interact in OSA and explore the functional consequences of such interactions. EGFR and Ron phosphorylation was present in canine OSA tumor tissues, and Met was associated with EGFR and Ron in canine OSA cell lines. High Ron expression was prognostic for survival. Gefitinib (small molecule EGFR inhibitor) and crizotinib (small molecule Met inhibitor) inhibited OSA cell proliferation in an additive manner. Prolonged TGF alpha exposure promoted Met phosphorylation. Co-activation of EGFR and Met with their ligands resulted in amplified ERK1/2 and STAT3 phosphorylation. These data indicate that Met, Ron, and EGFR functionally interact in canine OSA, alter (open full item for complete abstract)

Committee: Cheryl London (Advisor); William Kisseberth (Committee Member); Carlos Alvarez (Committee Member); Ramiro Toribio (Committee Member) Subjects: Oncology

Doctor of Philosophy, The Ohio State University, 2010, Entomology

Methoprene tolerant (Met), a member of the bHLH-PAS family of transcriptional regulators, has been implicated in juvenile hormone (JH) signaling in Drosophila melanogaster. Met mutants are resistant to the toxic and morphogenetic defects of exogenous JH application. A paralogous gene in D. melanogaster, germ cell expressed (gce), forms JH-sensitive heterodimers with MET, but a function for gce has not been reported. DmMet orthologs from three mosquito species are characterized and, based on sequence analysis and intron position, are shown to have higher sequence identity to Dmgce than to DmMet. An evolutionary scheme for the origin of Met from a gce-like ancestor gene in lower Diptera is proposed. RNAi-driven underexpression of Met in the Yellow Fever mosquito, Aedes aegypti, results in the concomitant reduction of putative JH-inducible genes, suggesting involvement in JH signaling. The viability of D. melanogaster Met mutants is thought to result from functional redundancy conferred by gce. Therefore, genetic manipulation of gce expression was used to probe the function of this gene. Overexpression of gce was shown to alleviate preadult, but not adult Met phenotypes. RNAi-driven underexpression of gce resulted in preadult lethality in both Met+ and Met mutant backgrounds. Therefore, unlike Met, gce is a vital gene. Evolutionary analysis of 12 Met and gce orthologs showed that these genes are conserved across the genus Drosophila. Additionally, distinct signatures of selective pressure were identified in Met and gce via dN/dS analysis. The paucity of introns in Met relative to gce supports the notion of a retrotransposition mechanism of duplication, through which Met arose from a gce-like ancestor following the divergence of higher and lower Diptera. Furthermore, RT-PCR analysis revealed discrete embryonic expression profiles for Met and gce. Together, these results show a degree of post-duplication subfunctionalization.

Committee: Thomas G. Wilson PhD (Advisor); David Denlinger PhD (Committee Member); Amanda Simcox PhD (Committee Member); H. Lisle Gibbs PhD (Committee Member) Subjects: Molecular Biology

Master of Science, The Ohio State University, 2008, Materials Science and Engineering

Titanium and its alloys are comparatively recent newcomers to the metallurgical market. They are gaining widespread acceptance for use in the recreational, aerospace, biomedical, petro-chemical, and commercial processing industries due to their combination of unique and advantageous properties, including high strength, low density, and superior corrosion resistance to most aggressive agents. The material properties of titanium and its alloys can be optimized and tailored by engineering the microstructure via control of chemistry, processing route, and heat treatment. The morphology of the two crystallographic allotropic phases can be manipulated to refine the structure and produce desirable mechanical property combinations. Microstructural constitution of the titanium alloys is classified according to the dominant phase within the alloy; alpha + beta (α + β) titanium alloys are the most widely used alloys. The temperature of the final heat treatment of the α/β components is governed by the service requirements. In order to evaluate the behavior of these alloys for future applications, it is imperative that the microstructural features and characteristics be quantified and examined on a spatial dimension. The Robo-Met.3D is a high precision robotic serial sectioning device that can fulfill this need. Initially, several months were spent resolving problems with the functioning of the Robo.Met.3D. Two-dimensional (2-D) stereology was done on Timetal 550 using automated batch processing with Adobe Photoshop and Fovea Pro. Images from different locations on the gage were obtained and compared. Final data demonstrated quantitative differences which were the result of the heat treatment. Discrepancies and inconsistencies in the data were identified as limiting factors in the reproducibility of the procedure in future work. Serial sectioning using focused ion beam (FIB) was performed using Timetal 550, and three-dimensional (3-D) reconstruction was done using IMOD. Robo-Me (open full item for complete abstract)

Committee: Hamish Fraser (Advisor); Yunzhi Wang (Committee Member) Subjects: Materials Science

Doctor of Philosophy, Case Western Reserve University, 2009, Biochemistry

Ski is the most studied member of a family of proteins all sharing a conserved Dachshund homology domain. It has been implicated in oncogenic transformation, myogenic conversion of avian embryo fibroblasts and also many aspects of vertebrate development, especially myogenesis. Ski-/- mice exhibit severe defects in skeletal muscle and die at birth, yet little is know about either the underlying mechanisms or the role of Ski in adult muscle regeneration. In these studies, I used Ski knockout mice and C2C12 myoblast cultures to address these issues, respectively. Detailed analysis of Ski-/- embryos revealed dramatically reduced hypaxial muscles but less affected epaxial muscles. The reduced number of myogenic regulatory factor positive cells in Ski-/- mice suggested an insufficient myogenic cell pool to support muscle formation. However, both the dermomyotomal hypaxial progenitors and myotomal epaxial progenitors formed and committed to myogenic fate appropriately. The hypaxial muscle defect in Ski-/- mice was not caused by abnormal proliferation, terminal differentiation or apoptosis of the myogenic cells either, but due to impaired migration of embryonic hypaxial progenitors. Surprisingly, the normal distribution of fetal/postnatal myogenic progenitors in Ski-/- mice suggested different effects of Ski on the behaviors of embryonic and fetal/postnatal myogenic progenitors. In addition, although not affecting the terminal differentiation of embryonic myogenic cells, Ski was necessary for that of adult satellite-cell derived C2C12 myoblasts as evidenced by impaired myotube formation and reduced induction of genes essential for myogenic differentiation in the absence of Ski. This function was mainly mediated by Ski's ability to form a complex with Six1 and Eya3 and activate Myog transcription through a MEF3 site. It is important in the future to further study mechanisms underlying the contrasting effects of Ski on embryonic, fetal and adult muscle development, to investi (open full item for complete abstract)

Committee: David Samols PhD (Committee Chair); Ed Stavnezer PhD (Advisor); Clemencia Colmenares PhD (Committee Member); Nikki Harter PhD (Committee Member); Lynn Landmesser PhD (Committee Member) Subjects: Biomedical Research

Doctor of Education, University of Akron, 2006, Educational Administration

The purpose of this study was to determine what effect met expectations have on student outcomes in web based courses. More specifically, do discrepancies between the initial course expectations and their perceptions during the course relate to student outcomes, such as satisfaction, motivation, psychological withdrawal, organizational citizenship behavior, and performance. In addition, it was hypothesized that novice web based learners would have more unmet expectations than experience web learners. To measure met expectations, web based students were surveyed at the beginning of the term and after the midterm. The difference between the expectations and perceptions resulted in difference scores, which served as the measure of met expectations. The difference scores were calculated in terms of direction and magnitude. An existing 13 item measure of student expectations in the classroom was used (Yorges, 2005). Dependent variable items were included on the second questionnaire. Surveys were administered to university students (n=94) via an online survey program. The results of the study found that unmet expectations have an adverse effect on satisfaction, motivation, and psychological withdrawal. Performance and Organizational Citizenship Behavior produced mixed results. No significant difference was found between unmet expectations for novice and experienced web course learners; however, it is important to note that every participant had taken at least one web based course in the past. Realistic Course Previews and implications for online instruction are discussed.

Committee: John Hirschbuhl (Advisor) Subjects: Education, Technology