Master of Science, The Ohio State University, 2017, Genetic Counseling

Purpose: To assess the frequency of PTEN pathogenic variants in a cohort of pediatric subjects with autism spectrum disorder (ASD), intellectual disabilities (ID), and/or global developmental delays (GDD), in the presence of macrocephaly. Methods: Retrospective chart review of subjects who were evaluated through the Nationwide Children's Hospital Child Development Center between January 1, 2015 and June 30, 2016 and received a diagnosis of ASD, ID, and/or GDD, and had macrocephaly. Medical record was abstracted to determine whether PTEN gene analysis was ordered, if testing was completed, and the results of testing. Results: One hundred eight subjects who met the study criteria had PTEN genetic testing ordered during this period. Fifty-eight subjects completed PTEN genetic testing. No PTEN pathogenic variants were identified (0/58; 95% CI: 0.0-6.3). Discussion/Conclusion: This data revealed that the frequency of PTEN pathogenic variants in subjects with a diagnosis of ASD, ID, and/or GDD in the presence of macrocephaly is less than the previously reported estimate of 10% in the literature.

Committee: Dawn Allain MS, LGC (Advisor); Emily Hansen-Kiss MS, MA, LGC (Committee Member); Robert Pilarski MS, LGC; MSW (Committee Member); Karen Ratliff-Schaub MD (Committee Member) Subjects: Genetics

Doctor of Philosophy, Case Western Reserve University, 2023, Molecular Medicine

Germline PTEN variants (PTEN hamartoma tumor syndrome, PHTS) confer up to 85-91% lifetime risk of female breast cancer (BC). BCs arising in PHTS are clinically distinct from sporadic BCs, including younger age of onset, multifocality, and an increased risk of second primary BCs. Yet, there is no previous investigation into the underlining genomic landscape of this entity. We sought to address the hypothesis that BCs arising in PHTS have a distinct genomic landscape compared to sporadic counterparts. We performed and analyzed exome sequencing from 44 breast tissues from women with germline PTEN variants who developed BC. The control cohort comprised of 497 sporadic BCs from The Cancer Genome Atlas (TCGA) dataset. We demonstrate that PHTS-derived BCs have a distinct somatic mutational landscape compared to the sporadic counterparts, namely second somatic hits in PTEN, distinct mutational signatures and increased genomic instability. The PHTS group had a significantly higher frequency of somatic PTEN variants compared to TCGA (22.7% versus 5.6%; odds ratio [OR] 4.93; 95% confidence interval [CI] 2.21 to 10.98; p<0.001), and a lower mutational frequency in PIK3CA (22.7% versus 33.4%; OR 0.59; 95% CI 0.28 to 1.22; p=0.15). Somatic variants in PTEN and PIK3CA were mutually exclusive in PHTS (p=0.01), but not in TCGA. There appear to be two genomically distinct groups of PHTS BCs, depending on the pathogenicity of underlying germline PTEN variants. We then examined copy number variations (CNV) and expression data to further characterize the somatic landscape of PHTS-derived BC. To examine CNV, we used the same exome sequencing data from 44 PHTS-derived BC cases described above and an expanded TCGA cohort with 558 women with sporadic BCs. We demonstrated that PHTS-derived BCs have several distinct CNV peaks compared to TCGA. Furthermore, RNA sequencing data revealed that PHTS-derived BCs have distinct inferred immunologic cell types, which points toward cancer immune evas (open full item for complete abstract)

Committee: Charis Eng (Advisor); Thonas LaFramboise (Committee Member); Ruth Keri (Committee Member); Jonathan Smith (Committee Chair) Subjects: Biology; Genetics; Oncology

Master of Sciences, Case Western Reserve University, 2014, Genetic Counseling

Breast carcinoma is a primary malignant tumor occurring in PTEN Hamartoma Tumor syndrome (PHTS). PHTS is caused by germline mutations in the tumor suppressor gene PTEN. Little is known about the histopathologic features and molecular profile of PHTS-related breast cancers. Furthermore, no data have been published on blood-PTEN/pAKT protein expression in individuals with germline PTEN mutations or other potential predictors of PTEN mutation status. Histopathological review of original Hematoxylin and Eosin slides demonstrated that apocrine features, atypical apocrine adenosis, and atypical ductal hyperplasia are distinctive histopathological features of PHTS-related breast tumors. A distinct PHTS-associated molecular profile was not identified; the association of PHTS-related breast cancers with a molecular apocrine profile was not confirmed. Furthermore, we determined that low blood-PTEN protein and/or high blood-pAKT expression, as well as the Cleveland Clinic PTEN risk score, may be used as predictors of germline PTEN mutations in Cowden syndrome/CS-like presentations of breast cancer.

Committee: Anne Matthews RN, PHD (Committee Chair); Anna Mitchell MD, PhD (Committee Member); Michell Merrill MS, CGC (Committee Member); Jessica Mester MS, CGC (Committee Member); Charis Eng MD, PhD (Committee Member) Subjects: Genetics

Doctor of Philosophy, Case Western Reserve University, 2024, Molecular Medicine

PTEN hamartoma tumor syndrome (PHTS) is a genetic disorder affecting individuals with germline PTEN variants. The affected individuals have a wide spectrum of clinical features ranging from cancer to neurodevelopmental disorders (NDD), including autism spectrum disorder (ASD). However, factors that underlie such phenotypic variability remain elusive, making it impossible to predict clinical outcomes. Here, we investigate germline genomic diversity as a modulator for the development of NDD versus cancer in PHTS. Genotype data of 376 individuals of European ancestry with PHTS were collected. Study participants included individuals with PHTS and NDD (n=117) and no-NDD (n=259), the former including n=57 with ASD and the latter including n=175 with cancer. Homozygosity burden was measured in sets of functionally relevant genes pertinent to NDD and cancer. Conservative filtration of homozygous variants was applied to identify variants in exonic or splicing sites for pathway analysis and with deleterious effects for collapsed homozygous variants analysis. Logistic regression models were performed with 10-fold cross validation to predict NDD/ASD phenotypes. We found significant enrichment of homozygous common variants (MAF≥0.01) but not rare variants (MAF<0.01) in genes involved in inflammatory processes and NDD-associated genes with low-confidence. Notably, in the ASD subgroup, homozygous common variants were enriched in genes involved in differentiation, inflammatory processes and chromatin structure regulation, NDD-associated genes with high-confidence, and regions with pathogenic copy number variants. Pathway enrichment analysis of genes harboring qualifying homozygous variants revealed pathways germane to NDD/ASD, including neuroinflammation, axonal guidance, and synaptogenesis signaling. Collapsing analysis with stringent filtration of homozygous variants suggested candidate modifier NDD/ASD genes, including GABRA4 (p=0.029) and CX3CR1 (p=0.016). Finally, prediction m (open full item for complete abstract)

Committee: Charis Eng MD, PhD (Advisor); Jonathan Smith PhD (Committee Chair); Robyn Busch PhD (Committee Member); Ming Hu PhD (Committee Member); Daniel Blankenberg PhD (Committee Member) Subjects: Genetics; Health Sciences; Medicine; Molecular Biology

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

Principal component analysis (PCA) is a data analysis technique used to reduce the dimension of a data set while retaining key patterns of variation by transforming the data to a lower-dimension space defined by orthonormal basis vectors that capture the directions of maximal variation. A novel technique named logistic PCA (LPCA) was developed that allows researchers to make use of benefits of PCA analysis in the study of data sets containing binary variables, allowing for more widespread use of these methods in areas of study frequently examining binary data, such as biomedical science and healthcare. We apply logistic PCA method to two data sets, the first comprised of data from tissue samples obtained from patients diagnosed with breast cancer and the second comprised of data from select genetic profiles of individuals diagnosed with brain tumor. An initial simulation study was performed to examine randomly-generated binary data from settings with a known clustering structure to evaluate retention of clustering in low-dimension plots created using PCA, LPCA, and t-distributed stochastic neighbor embedding (t-SNE), another frequently-utilized data analysis technique. Results revealed that LPCA consistently outperforms PCA in terms of reconstruction error in settings where probability parameters for clusters are close to 0.5 and that LPCA and PCA perform comparably in settings with more extreme probability parameters. LPCA and t-SNE also show comparable clustering in the two-dimensional plots. In analysis of the cancer-related data, two-dimensional plots for data embedding were generated, and principal component loadings were obtained from each of the data sets using LPCA and PCA, and used to provide interpretations of data patterns in the context of cancer-related biomedical science and healthcare. Analysis revealed that interpretations of LPCA loadings provide information consistent with established biomedical research findings as well as new information and that (open full item for complete abstract)

Committee: Yoonkyung Lee (Advisor); Asuman Turkmen (Committee Member) Subjects: Applied Mathematics; Biology; Genetics; Medicine; Oncology; Statistics

Doctor of Philosophy, Miami University, 2024, Cell, Molecular and Structural Biology (CMSB)

Lens epithelial explants serve as a valuable in vitro model for studying cellular processes related to lens development and differentiation. Despite significant research, key mechanisms underlying lens fiber cell differentiation and related signaling pathways remain unclear. This dissertation aims to address this gap by investigating the roles of key genes, transcription factors, and microRNAs in lens development and fiber cell differentiation through multiple studies involving RNA-sequencing, ATAC-sequencing, and other molecular biology techniques. Chapter 2 focuses on the influence of vitreous humor on lens epithelial explants, revealing that it increases chromatin accessibility and upregulates genes related to lens fiber cell differentiation while downregulating those associated with lens epithelial cells. The study's unbiased analysis indicated that RUNX, SOX, and TEAD transcription factors might drive these gene expression changes, providing a basis for further exploration. Chapter 3 investigates the role of Fgfrs and Pten in lens fiber cell differentiation and immune responses using RNA-sequencing on explants lacking Fgfrs, Pten, or both. The results show that the loss of Fgfr signaling impairs vitreous-induced fiber differentiation and immune responses, while the loss of Pten can partially rescue these effects. Gene set enrichment analysis suggested that PDGFR-signaling might mediate this rescue, which was confirmed with immunohistochemistry showing beta crystallin expression, indicating fiber cell differentiation. Chapter 4 explores the functional roles of specific microRNAs in lens development. A comprehensive analysis of miRNA transcripts revealed that the loss of miR-26 leads to postnatal cataracts and significant changes in gene expression, with abnormal increases in genes related to neural development, inflammation, and epithelial-to-mesenchymal transition. This demonstrates that miR-26 is crucial for normal lens development and cataract prevention. (open full item for complete abstract)

Committee: Michael L. Robinson (Advisor); Paul F. James (Committee Chair); Justin M Saul (Committee Member); Chun Liang (Committee Member); Katia Del Rio-Tsonis (Committee Member) Subjects: Bioinformatics; Biology; Cellular Biology; Molecular Biology

Doctor of Philosophy, Case Western Reserve University, 2024, Systems Biology and Bioinformatics

Cancer and autism spectrum disorder/developmental delay (ASD/DD) are two common clinical phenotypes in individuals with germline PTEN variants (PTEN hamartoma tumor syndrome, PHTS). However, the accurate prediction of these two disparate phenotypes (cancer vs. ASD/DD) for PHTS at the individual level remains unestablished, despite the availability of population level prevalence estimates. Burgeoning studies have shown that genomic and metabolomic factors may act as modifiers of ASD/DD versus cancer in PHTS. We also found that mitochondrial complex II variants occurring in 10% of PHTS individuals modify breast cancer risk and thyroid cancer histology. Therefore, mitochondrial pathways could act as important factors in PHTS phenotype development. As such, in the first project, we investigated the mtDNA landscape extracted from whole genome sequencing data from 498 PHTS individuals, including 164 with ASD/DD (PHTS-onlyASD/DD), 184 with cancer (PHTS-onlyCancer), 132 with neither ASD/DD nor cancer (PHTS-neither), and 18 with both ASD/DD and cancer (PHTS-ASDCancer). We demonstrate that PHTS-onlyASD/DD have significantly higher mtDNA copy number compared to the PHTS-onlyCancer group. Additionally, the PHTS-neither group has significantly higher mtDNA variant burden than the PHTSASDCancer group. 1 Relatedly, maintenance of genome integrity is one of the key biological functions of PTEN; however no integrative studies have been conducted to quantify the DNA damage response (DDR) in individuals with PHTS and to relate the cellular phenotype to organismal phenotypes and genotypes. Therefore, in the second project, we used 43 PHTS patient-derived lymphoblastoid cell lines (LCLs) to investigate the associations between DDR and PTEN genotypes and/or the clinical (organismal) phenotypes of ASD/DD vs. cancer. We found that PTEN nonsense variants are associated with inefficient DNA damage repair. In contrast, we observed the fastest DNA damage repairing rates in LCLs from indi (open full item for complete abstract)

Committee: Charis Eng (Advisor); Jacob Scott (Advisor); Alexandru Almasan (Committee Member); Daniela Calvetti (Committee Member); Mehmet Koyutürk (Committee Chair) Subjects: Bioinformatics; Biomedical Research

Doctor of Philosophy, Case Western Reserve University, 2023, Molecular Medicine

Autism Spectrum Disorders (ASDs) are a group of neurodevelopmental disorders for which there is no direct treatment. Understanding the disease mechanisms may lead to future therapeutic targets. In this thesis, we performed bi-directional CRISPR-Cas9 genome editing on induced pluripotent stem cells (iPSCs) derived from individuals with ASD with macrocephaly as well as controls, and uncovered that in addition to PTEN p.Ile135Leu variant, ASD genetic backgrounds also contributed to dysregulating cortical neurogenesis in both 2D neural progenitor cells and 3D cortical organoid models. Surprisingly, ASD specifc PTEN p.Ile135Leu variant dysregulates cortical neurogenesis in an ASD genetic background dependent fashion, as we found that this variant led to overproduction of neural progenitor cell (NPC) subtypes including intermediate progenitor cells (IPCs) and outer radial glia cells (oRGs) as well as neuronal subtypes such as deep and upper layer neurons in the ASD genetic background but not in the control genetic background in the cortical organoids. This study provides strong evidence that both an ASD-specifc PTEN p.Ile135Leu variant and autism genetic background are contributing to the cortical neurogenesis dysregulation. We also developed a lineage tracing system to track neurogenesis in human cortical organoids and applied this system to a control iPSC line as well as autistic isogenic CTNNB1 iPSC lines, we uncovered that the majority of the cortical neurons in the cortical organoids were indirectly generated through IPCs, and neurons derived from diferent lineages were transcriptionally distinct. An ASD-linked CTNNB1 p.Gln76* variant altered the lineage specific production of deep and upper layer neurons as well as the landscape of gene expression profiles among and within different neural progenitor lineages of both deep and upper layer neuron production. Overall, this thesis provides direct evidence that variants in the PTEN and WNT pathways as well as ASD (open full item for complete abstract)

Committee: Anthony Wynshaw-Boris M.D., Ph.D. (Advisor); Justin Lathia Ph.D. (Committee Chair); Tara DeSilva Ph.D. (Committee Member); Fulai Jin Ph.D. (Committee Member); Charis Eng M.D., Ph.D. (Committee Member) Subjects: Genetics; Neurosciences

PhD, University of Cincinnati, 2022, Medicine: Pathobiology and Molecular Medicine

Malignant gliomas such as glioblastoma are highly heterogeneous with distinct cells of origin and varied genetic alterations. Analysis of TCGA databases reveals that co-mutations of PTEN and TP53 are most significantly enriched in human high-grade gliomas. Mice with PTEN/p53 ablation mediated by multilineage-expressing human GFAP (hGFAP)-promoter-driven Cre lines develop glioma but with incomplete penetrance and long latency. However, the specific cell lineages and states that are susceptible to PTEN/p53-loss-induced malignant transformation remain elusive. Unexpectedly, ablation of Pten and Trp53 in Nestin+ neural stem cells (NSCs) or Pdgfra+/NG2+ committed oligodendrocyte precursor cells (OPCs), two major cells of origin in glioma, did not induce glioma formation in mice. Strikingly, mice lacking Pten and Trp53 in Olig1+/Olig2+ intermediate-lineage precursors prior to the committed OPCs develop high-grade gliomas with 100% penetrance and short latency. The resulting tumors exhibit distinct tumor phenotypes and drug sensitivities from NSC- or OPC-derived glioma subtypes. Integrated transcriptomic and epigenomic analyses revealed that PTEN/p53-loss induced activation of oncogenic pathways including HIPPO-YAP and PI3K signaling to promote malignant transformation. Targeting the core regulatory circuitries YAP and PI3K signaling effectively inhibited tumor cell growth. Thus, our multi-cell state in vivo mutagenesis analyses suggests that transit-amplifying states of Olig1/2-intermediate-lineage precursors predispose to PTEN/p53-loss-induced transformation during gliomagenesis, pointing to subtype-specific treatment strategies for gliomas with distinct genetic alterations. The establishment of glioma mouse models is critical for defining cellular alterations and initiating processes during glioma development. I have developed a virus-induced glioma animal model with a retrovirus that overexpresses oncogenic Pdgfb or activating Ras mutant in conjunction with domin (open full item for complete abstract)

Committee: Qing Richard Lu Ph.D. (Committee Member); Vladimir Bogdanov Ph.D. (Committee Member); Timothy Phoenix (Committee Member); Jose Cancelas-Perez M.D. (Committee Member); Kenneth Campbell Ph.D. (Committee Member) Subjects: Oncology

Doctor of Philosophy, Case Western Reserve University, 2021, Genetics

Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting approximately 1 in 58 children by age 8 in the United States and defined by deficits in social communication accompanied by restricted and repetitive interests. ASD is highly heritable with many risk genes of varying penetrance and effect size. Germline mutations in PTEN account for up to 10% of cases of macrocephalic ASD and has been shown to be one of the most common causes of genetic ASD. Although the genetic relationship between PTEN-ASD is well described, the contributions of PTEN function to ASD pathology have yet to be delineated with clarity and rigor. Given some of the preliminary evidence that suggests subcellular localization associates more strongly with PTEN-related neurodevelopmental phenotypes, we have focused on modeling mutations that selectively partition PTEN to the cytoplasm or nucleus. We utilized two complementary mouse models, the cytoplasmic-predominant Pten (Pten m3m4/m3m4) and nuclear-predominant Pten (Pten Y68H/+). In the cytoplasmic-predominant model, we demonstrated that genes related to pathways such as complement activation, neuroinflammation, and synaptic pruning are upregulated in the cortex. This expression pattern features decreased synaptic protein expression with coincident microglial activation. We validated these findings in vitro and showed microglia are capable of increased synaptic pruning when co-cultured with neurons. In our nuclear-predominant model, we found that the Pten Y68H/+ model showed behavioral deficits similar to ASD, i.e. decreased sociability and increased repetitive behavior. Moreover, in vivo, microglia are activated with increased expression of complement and genes involved in neuroinflammation, while in vitro, we found microglia were capable of enhanced phagocytosis. Overall, our studies provide evidence that Pten is a potent negative regulator of microglial activation, phagocytosis, and synaptic pruning regardless of subcellular con (open full item for complete abstract)

Committee: Charis Eng MD, PhD (Advisor); Hua Lou PhD (Committee Chair); Anthony Wynshaw-Boris MD, PhD (Committee Member); Ranjan Dutta PhD (Committee Member) Subjects: Developmental Biology; Genetics; Neurobiology

Doctor of Philosophy, Case Western Reserve University, 2021, Molecular Medicine

Germline alterations of the gene encoding PTEN, a canonical tumor suppressor, contributes to risk of both benign and malignant neoplasia and neurodevelopmental phenotypes, meaning germline PTEN mutations associate with specific rare cancer syndromes (e.g., Cowden syndrome) and autism spectrum disorder (ASD). To describe the PTEN-associated phenotypic heterogeneity, the molecular diagnosis PTEN Hamartoma Tumor Syndrome (PHTS) was established encompassing several clinical entities. The cancer and autism association is a striking, perplexing juxtaposition, inspiring study. Given the mature connection between cancer processes and canonical aspects of PTEN function (i.e. suppression of PI3K/AKT/mTOR signaling), we have focused on PTEN function in neurodevelopmental pathologies like ASD. To investigate this somewhat intractable question (it is challenging to study molecular features of brains in living individuals), we developed two complementary murine models of Pten disruption. The Ptenm3m4 model exhibits cytoplasmic-predominant expression, while the PtenY68H model exhibits nuclear-predominant expression. Prior study of both models found behavioral, cellular, and molecular abnormalities reminiscent of autism. These models are suited for insight into PTEN-ASD pathophysiology and understanding the neurobiological effects of localization-associated, separation-of-function mutants. Herein, we demonstrate that the Ptenm3m4 model shows aberrant alternative splicing with associated changes in splicing factors, U2af2 and Srrm4. Additionally, a multi-omic survey of the Ptenm3m4 brain found dysregulation of molecules and pathways implicated in autism biology, identifying Pten and Psd-95 as regulatory hubs important to initiating and perpetuating observed phenotypes. Intriguingly, these molecular phenotypes undergird numerous changes in neurobiology, including changes in neural stem cell (NSC) maturation, oligodendrocyte (OL) differentiation, and microglia activation. In the PtenY (open full item for complete abstract)

Committee: Charis Eng MD, PhD (Advisor); Zhenghe Wang PhD (Committee Chair); Alex Almasan PhD (Committee Member); George Stark PhD (Committee Member); Rick Padgett PhD (Committee Member); Ruth Keri PhD (Committee Member) Subjects: Genetics; Neurosciences

PhD, University of Cincinnati, 2020, Medicine: Molecular and Developmental Biology

Deficiency in Phosphatase and Tensin Homolog deleted on Chromosome 10 (PTEN) (also referred to as MMAC1/TEP1) is known to contribute to multiple diseases of the brain including brain tumors, autism spectrum disorders and epilepsy. PTEN is a dual-specificity phosphatase that negatively regulates the phosphatidylinositol 3-kinase (PI3K) pathway by dephosphorylating phosphatidylinositol (3,4,5)-trisphosphate (PIP3), generating phosphatidylinositol (4,5)-bisphosphate (PIP2). Overactive PI3K signaling increases PIP3 leading to accelerations in cell cycle transition, proliferation and cell size. In this body of work, I assessed PTEN deficiency in the brain in the context of both cancer and neurodevelopmental disorders. In the first studies presented here (Chapters 2 and 3) we assess high grade gliomas. In Chapter 4, we assess PTEN deficient autism and epilepsy. Each project has the commonality of utilizing inhibition of the PI3K pathway to counteract the effects of PTEN deficiency but the therapeutic strategies used for each disorder will differ. For Chapter 2, we found a subset of tumors which have a favorable response to PI3K pathway inhibition, as assessed by proliferation and apoptosis in a novel genetically engineered mouse model which is PTEN deficient. This work seeks to identify the molecular differences in tumors which are reported as responsive to PI3K inhibition as compared to tumors that were not responsive. In Chapter 3, we describe a novel mouse model which represents a subset of pediatric high grade glioma. Due to the driving mutations in the PI3K pathway, including a mutation in PTEN, we assessed both monotherapy PI3K inhibition as well as a monotherapy downstream effector of PI3K (mTOR). Although preliminary, the tumors showed a marked reduction in proliferation. Finally, in Chapter 4, we assessed a therapeutic approach derived from PTEN-deficient cancers and apply it to PTEN-deficient autism and seizure disorders in a neuron-specific PTEN-deficient mo (open full item for complete abstract)

Committee: Christina Gross Ph.D. (Committee Chair); Lionel Chow M.D. (Committee Member); Steve Danzer Ph.D. (Committee Member); Charles Vorhees Ph.D. (Committee Member); Ronald Waclaw Ph.D. (Committee Member) Subjects: Biology

Doctor of Philosophy, The Ohio State University, 2020, Biomedical Engineering

The extracellular matrix is extensively reorganized throughout breast cancer progression. This reorganization contributes to cancer cell invasion and intravasation and is an independent prognostic factor for breast cancer patients. Cancer-associated fibroblasts appear to play a major role in this reorganization but the cellular signaling pathways contributing to this reorganization remain unclear. We show here that loss of the tumor suppressor phosphatase and tensin homolog (Pten) in fibroblasts promotes extracellular matrix alignment both in vitro and in vivo through increasing cell traction forces. Furthermore, low stromal PTEN expression correlated with high mammographic density, one of the major risk factors for breast cancer development. Matrix reorganization was concomitant with a marked increase in collagen deposition within the mammary gland. We therefore investigated the mechanism of collagen deposition and showed that loss of PTEN upregulated SPARC, which mediated both collagen and fibronectin assembly without modulating cell traction force. To further determine how Pten loss connected to matrix alignment, we designed a novel screening platform to examine matrix alignment in vitro using fibroblast-derived matrices, automated microscopy, and automated image analysis through MATLAB. We discovered a number of novel matrix alignment modulators, including protein kinase C (PKC), dual specificity tyrosine regulated kinase 1b (DYRK1b), platelet-derived growth factor receptor β (PDGFRβ), and Janus kinase (JAK), among others. The effect of these markers on patient survival was examined using publicly available patient datasets. Finally, we examined the effects of hypoxia and matrix metalloproteinase activity on matrix organization.

Committee: Jennifer Leight (Advisor); Samir Ghadiali (Committee Member); Jonathan Song (Committee Member) Subjects: Biomedical Engineering

MS, University of Cincinnati, 2019, Medicine: Biomedical Research Technology

Epilepsy is a crippling neurological condition that is characterized by episodes of unprovoked seizures. Current antiepileptic drugs are effective at controlling seizures, but do not cure or modify the disease, and are ineffective for a third of the patient population with epilepsy. There are no clinically proven preventatives for patients at risk of developing epilepsy. The mTOR pathway has emerged as a promising new target as a disease-modifying therapy for epilepsy. Circumstantial evidence has linked mTOR to epileptogenesis through hyper activated signaling identified in acute seizures, status epilepticus, and traumatic brain injuries, yet the underlying mechanisms behind these effects remain unclear. mTOR signaling has been found to be dramatically increased in the dentate gyrus during temporal lobe epileptogenesis. The studies reported in this thesis look at the mTOR project from different projects: 1) Developing viral strategies to selectively delete mTOR from the Hippocampus and 2) Developing a model of Focal Cortical Dysplasia.

Committee: Rolf Stottmann PhD (Committee Chair); Steve Danzer Ph.D. (Committee Member); Christina Gross Ph.D. (Committee Member) Subjects: Neurology

Doctor of Philosophy, The Ohio State University, 2018, Comparative and Veterinary Medicine

Endometrial carcinomas arise from the epithelium of the uterine glands and are the most common gynecological malignancy. There are two major clinical subtypes of endometrial carcinomas, which present with distinct epidemiological, histological and molecular associations. Type I endometrial carcinomas account for nearly 80% of cases and are associated with a more favorable prognosis. Epidemiologically, affected women are middle-aged and peri-menopausal. Increased estrogen signaling appears to be involved in the pathogenesis of type I tumors because risk factors include estrogen supplementation, late menopause, history of tamoxifen treatment for breast cancer, obesity and polycystic ovarian disease. Histologically, these tumors arise from a background of endometrial hyperplasia and neoplastic cells are well-differentiated. PTEN mutations or loss of expression occur in 80% of type I tumors. In contrast, type II carcinomas are associated with poor clinical outcome and affected women are post-menopausal. Histologically, type II tumors arise from an atrophic endometrium and the neoplastic cells are poorly differentiated with significant nuclear atypia. TP53 mutations occur in 90% of type II tumors. Using mouse models, we attempt to further our understanding of the pathogenesis of endometrial carcinoma. We show that genetic ablation of the Pten locus is sufficient to drive malignant transformation of the uterine epithelium and a proportion of affected mice develop invasive and metastatic disease. Importantly, these tumors are phenotypically similar to type I “endometrioid” carcinomas observed in women and we propose that these mice may serve as an important preclinical model for studying the pathogenesis of type I endometrial carcinoma or novel therapies for its prevention and treatment. Interestingly, genetic ablation of the Trp53 locus does not transform uterine epithelium within the timeframes of our study indicating that there are other factors necessary to drive type (open full item for complete abstract)

Committee: Gustavo Leone PhD (Advisor); Michael Oglesbee DVM, PhD (Advisor); David Cohn MD (Committee Member); Takeshi Kurita PhD (Committee Member) Subjects: Cellular Biology; Histology; Medicine; Molecular Biology; Nutrition; Pathology

PhD, University of Cincinnati, 2018, Pharmacy: Pharmaceutical Sciences/Biopharmaceutics

Epilepsy is a disease characterized by recurrent and unprovoked seizures. Temporal lobe epilepsy (TLE) is the most common form of partial epilepsy and is often refractory to treatment. Hypothetically, it originates in the temporal lobe of the brain, when the dentate gyrus (DG) of the hippocampus becomes compromised, which, otherwise, physiologically functions as a “filtering gate” to hyperexcitatory signals. Animal models were developed to outline mechanisms by which epilepsy occurs. In 2012, Pun and colleagues have proven that deleting a gene, phosphatase and tensin homologue (PTEN) can cause epilepsy in mice. PTEN is an inhibitor in the mammalian target of rapamycin (mTOR) pathway. Deleting PTEN causes mTOR hyperactivation which leads to cellular changes that are considered hallmarks of the disease, for example: somatic and dendritic hypertrophy and appearance of aberrant basal dendrites. Despite the plethora of knowledge about the disease, it is still unknown how the morphological abnormalities develop with age, and whether or not, they are caused, at least in part, by seizures and what are the gender specific difference in the excitability and/or morphology in the model. Our guiding hypothesis is that PTEN deletion leads to cell intrinsic changes which worsen overtime. Further, we hypothesize that disease severity may cause those changes to worsen in male and female mice. In chapter II, we modified the PTEN KO model of epilepsy to produce a “mild” phenotype in order to examine the growth trajectories of the PTEN knockout (KO) cells. Three different cohorts were used: 1) brainbow-expressing mice with low KO numbers that don't develop seizures and have an age range of 7-18 weeks, 2) biocytin-filled cells from animals with low KO numbers that don't develop spontaneous seizures and have a wide age range (15-36 weeks), and 3) biocytin-filled cells from animals with high KO numbers and a severe seizure phenotype. Findings from chapter II indicate (open full item for complete abstract)

Committee: Steve Danzer Ph.D. (Committee Chair); Steve Crone Ph.D. (Committee Member); Gary Gudelsky Ph.D. (Committee Member); Katherine Holland-Bouley M.D. Ph.D. (Committee Member); Jianxiong Jiang Ph.D. (Committee Member) Subjects: Neurology

Doctor of Philosophy, Case Western Reserve University, 2018, Pathology

Hereditary cancer syndromes serve as powerful models for uncovering cancer-relevant genes. Identification of cancer-predisposing genes not only facilitates gene-enabled molecular diagnosis, cancer risk assessment and gene-specific clinical management, but also offers valuable insights into therapeutically targetable pathways contributing to sporadic tumorigenesis. We study Cowden syndrome (CS) as a model for germline predisposition to cancer. CS is an autosomal dominant disorder characterized by high lifetime risks of epithelial cancers, with ~50% of patients wildtype for known predisposition genes. Using whole-exome and Sanger sequencing of a multi-generation CS family with thyroid and other cancers, we identified a pathogenic missense heterozygous variant in SEC23B (c.1781T>G, p.Val594Gly) that segregated with phenotype. SEC23B encodes Sec23 Homolog B, a component of coat protein complex II (COPII), transporting proteins from endoplasmic reticulum (ER) to Golgi apparatus. Interestingly, germline homozygous or compound heterozygous SEC23B mutations cause an unrelated disorder, Congenital Dyserythropoietic Anemia Type II, and SEC23B-deficient mice show secretory organ degeneration due to ER stress-associated apoptosis. Extending our genetic studies, we also found germline heterozygous SEC23B variants in 3/96 (3%) unrelated mutation negative CS probands with thyroid cancer, and in The Cancer Genome Atlas (TCGA), representing apparently sporadic cancers. We note that TCGA thyroid cancer dataset is enriched for unique germline deleterious SEC23B variants that were associated with a significantly younger age at onset. At the functional level, by characterizing the p.Val594Gly variant in a non-malignant thyroid cell line, we provide evidence that it is a functional mutation that results in ER stress-mediated cell colony formation and survival, growth, and invasion, reflecting aspects of a cancer phenotype. Importantly, these phenotypes occurred with absence of CDA II- (open full item for complete abstract)

Committee: Charis Eng MD, PhD (Advisor); Shigemi Matsuyama PhD (Committee Chair); Clive Hamlin PhD (Committee Member); George Stark PhD (Committee Member); Ruth Keri PhD (Committee Member); Thomas LaFramboise PhD (Committee Member) Subjects: Bioinformatics; Biomedical Research; Cellular Biology; Genetics

Doctor of Philosophy, The Ohio State University, 2017, Neuroscience Graduate Studies Program

Brain tumors affect over 680,000 people in the USA, with malignant brain tumors accounting for approximately 20% of these patients. Malignant brain tumors are among the most aggressive and deadly tumors, and can be divided to primary tumors that originate within the brain, and secondary tumors that spread from distant locations, known as brain metastatic tumors. The median survival for patients with glioblastoma, the most common primary malignant brain tumor, is 14.6 months following standard of care therapy, while the situation for patients with brain metastasis can be even worse. While primary and metastatic brain tumors affect males and females at different rates, sex as a biological variable remains an underinvestigated topic, with many tumor-related preclinical studies having a sex bias. Here we investigated sex as a biological variable in response to temozolomide, and reported a trend towards improved overall survival in male mice, but no significant differences between male and female mice in response to therapy (p=0.17). Brain tumor treatment continues to be a major challenge in oncology. The standard of care for brain tumors consists of maximal surgical resection followed by radiotherapy and chemotherapy. However, despite continued research and new approaches for a variety of other cancers, the prognosis for patients with malignant brain tumors is still extremely poor. Several tumor-specific barriers to therapy, including the blood-brain barrier and the brain tumor microenvironment, prevent many conventional drugs from being efficacious in this unique setting. Specific and effective treatments for brain tumors are still in urgent need in the clinic, however, insights into the mutational landscape of brain tumors has provided researchers with druggable targets to investigate. PTEN loss is common across a variety of tumor types, and is commonly lost in glioblastoma (~50%) and breast cancer (33-49%). Oncolytic viral therapy is a promising novel therapy (open full item for complete abstract)

Committee: Balveen Kaur PhD (Advisor) Subjects: Neurosciences

Doctor of Philosophy, The Ohio State University, 2017, Biomedical Sciences

The ability of pathogenic viruses to alter host metabolism has been recently characterized. Infection by the human adenovirus serotype 36 (AD36) promotes obesity in animal models and correlates to increased adiposity in humans, yet improves glycemic control. Based on in vitro studies, the E4ORF1 protein is responsible for both the adipogenic and insulin sparing properties of AD36 infection via insulin independent Akt activation. We generated a recombinant adeno-associated viral (rAAV) vector to express AD36E4ORF1. Through intravenous delivery we expressed AD36E4ORF1 in the livers of diabetic, insulin resistant, and wild-type mice. Hepatic AD36E4ORF1 improved glucose tolerance and attenuated hyperglycemia in obese diabetic Db -/- mice without improving insulin sensitivity. AD36E4ORF1 also reduced hyperinsulinemia and improved glucose tolerance in insulin resistant mice with diet induced obesity (DIO). Liver specific glucose uptake was increased without improving insulin sensitivity. Confirming the findings of previous in vitro studies, Akt activity was not only increased but also required for AD36E4ORF1 mediated glucose uptake. AD36E4ORF1 expression is a model of insulin independent AKT activation and provides a novel therapeutic mechanism to improve glycemic control in cases of insulin resistance. Next, we looked at how environmental factors might contribute to healthy aging and prevention of metabolic syndrome. Animals housed in a larger, more complex enriched environment (EE) are provided with increased somatosensory stimulation, physical exercise, and enhanced social interactions. Together, these stimuli increase expression of brain derived neurotrophic factor (BDNF) in the hypothalamus, activating a hypothalamic sympathoneural-adipocyte axis (HSA). In young animals, HSA activation has been shown to improve glycemic control and overall health but its impact in older animals has not been previously characterized. Middle-aged 10 month old female mice were h (open full item for complete abstract)

Committee: Lei Cao Ph.D. (Advisor); Denis Guttridge Ph.D. (Committee Member); Courtney DeVries Ph.D. (Committee Member); Kay Huebner Ph.D. (Committee Member) Subjects: Biomedical Research

Doctor of Philosophy, The Ohio State University, 2016, Biomedical Sciences

Understanding the cellular and molecular mechanisms that impact aging is important to improve accelerated aging diseases and promote healthy living in the aging population. Recent genetic studies provide clues on the mechanisms important in aging, specifically stem cell exhaustion, cellular senescence, telomere attrition and protein quality control mechanisms such as autophagy. Aging and some-age related diseases, such as pulmonary fibrosis are linked to these impaired mechanisms. The PTEN/PI3K/Akt/mTOR pathway is evolutionarily implicated and conserved in organismal longevity. In this pathway, PTEN promotes longevity by negatively regulating PI3K, Akt and mTOR activity. PTEN expression is down regulated in age-related diseases, such as cancer and idiopathic pulmonary fibrosis (IPF), resulting in activation of Akt and mTOR. These events promote cellular and organismal aging, which may drive pathogenic aging. In addition to PTEN as an important determinant of cellular longevity, telomerase activity and autophagy are also evolutionarily implicated and conserved in organismal aging. The overall objective of this proposal is to determine the impact of known aging pathways on organismal and lung aging in two parts. First, in Chapter 2, we elucidate how the loss of PTEN in mesenchymal stem cells (MSCs) impacts organismal aging. Second, we interrogate how the upregulation of DNA methyltransferases (DNMTs) target telomerase (Chapter 3) and autophagy genes (Chapter 4) in primary lung fibroblasts and lung tissues from IPF patients of different severity. We further demonstrate that DNMTs are upregulated via TGFß1in vitro (Chapter 5).

Committee: Joanna Groden PhD (Advisor); Clay Marsh MD (Advisor); Peter Mohler PhD (Committee Member); Susheela Tridanapani PhD (Committee Member) Subjects: Biomedical Research