Doctor of Philosophy, Case Western Reserve University, 2023, Pathology

Advancements in therapy have improved remission and prolonged survival for patients with B cell malignancies. Unfortunately, for many challenging cancer subtypes such as mantle cell lymphoma, most patients will still relapse and die from the cancer. Chimeric antigen receptor (CAR)-T cell therapy uses genetically modified T cells expressing CAR protein to recognize and kill cancers expressing a specific antigen, such as CD19. Although CD19 CAR-T therapy has been very effective against relapsed/refractory B cell cancers, antigen escape and relapse still occur in up to 40% of patients treated with CD19 CAR-T. This work describes the creation and validation of a novel, BAFF ligand-based CAR that aims to prevent antigen escape by being able to bind multiple BAFF receptors expressed by the cancer cell, rather than one antigen alone. Using cytotoxicity assays, we demonstrate the functionality and specificity of BAFF CAR-T cells in killing several types of B cell malignancies, and we further confirm their efficacy in several mouse models of cancer. These results have helped bring BAFF CAR-T therapy to Phase I clinical trials, and we hope they prove efficacious for patients with relapsed/refractory B cell malignancies. Meanwhile, interest has rapidly increased in natural killer (NK) cell-based immunotherapies. NK cells have important roles in cancer immunosurveillance and offer advantages over T cells in clinical safety and time-to-treatment. However, NK therapies face challenges in efficacy and persistence, often due to the presence of TGF-β, a powerful immunosuppressive cytokine that is frequently elevated in cancer patients and a primary cause of NK cell dysfunction. In this work, we characterize an undiscovered role of cyclin dependent kinase 5 (Cdk5) and its coactivator p35 in NK cell cytotoxicity. Using genetic tools to modulate Cdk5/p35 kinase activity in human NK cells, as well as using NK cells from p35 knockout mice, we show that Cdk5/p35 negatively regulates NK (open full item for complete abstract)

Committee: Reshmi Parameswaran (Advisor); Alex Huang (Committee Chair); John Letterio (Committee Member); Clive Hamlin (Committee Member) Subjects: Biology; Biomedical Research; Immunology; Medicine; Molecular Biology; Oncology

Master of Science, The Ohio State University, 2022, Genetic Counseling

The World Health Organization (WHO) recently included germline predisposition to myeloid malignancies as a new entity, recognizing it is clinically important to identify these individuals. Using DISCOVeRY-BMT cohorts, a study of almost 3,000 patient-HLA matched unrelated donor pairs reported to the Center for International Blood and Marrow Transplant (BMT) from 2000-11, we identified pathogenic (P) and likely pathogenic (LP) variants in cancer or myeloid malignancy related genes in leukemia patients and healthy blood or marrow donors, performed gene-based association with myeloid disease and determined if variants and/or genes impact overall survival after transplant. In 1684 acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients and 2246 unrelated healthy donors from DISCOVeRY-BMT ClinVar P/LP variants taken from Illumina HumanExome BeadChip genotype data and frequencies were calculated across both disease groups. Nonsense and missense variants were used for sequence kernel-based association testing as implemented in SKAT-O and likelihood ratio tests were used for single variant association and survival analyses. We identified 45 pathogenic/likely pathogenic variants in DISCOVeRY-BMT AML or MDS patients and/or donors; 12 autosomal dominant variants in 9 genes (3.1% of patients and 2.6% of donors) and 34 P/LP variants in 24 genes for autosomal recessive conditions identified in 203 patients (10.2%) and 243 donors (10.8%). The start codon, c.3G>A, DEAD/H-box helicase (DDX41) was the most frequent LP/P variant seen patients (11 de novo AML, 6 MDS patients) but no donors. The CHEK2 c.470T>C was the most frequent LP/P variant seen in donors (n=19); this variant was also patients (6 AML, 1 t-AML and 3 MDS). Survival analyses identified a germline non-internal tandem duplication/tyrosine kinase domain FLT3 variant, c.2383G>A associated with 1 year transplant related mortality in AML and MDS patients (P=6.6 x 10-5). Despite the small amount of exom (open full item for complete abstract)

Committee: Leigha Senter-Jamieson (Advisor); Pamela Brock (Committee Member); Julia Cooper (Committee Member) Subjects: Epidemiology; Genetics; Oncology

Doctor of Philosophy, The Ohio State University, 2019, Biomedical Sciences

Acute Myeloid Leukemia (AML) is the most common acute leukemia in adults affecting almost 12,000 people each year in the US. This disease is collectively characterized by an accumulation of rapidly proliferating neoplastic cells of the myeloid lineage with differentiation defects. In spite of the vast amount of information known about AML and the identification of favorable prognosis factors, a large percentage of patients relapse and succumb to this disease. In addition, the inter- and intra-tumor heterogeneity of AML makes the identification of therapeutic targets for this disease particularly challenging. Future studies are warranted to identify multi-targeted agents that could influence AML as a composite disease. A target that shows promise in targeting the bulk AML leukemic cell population is nicotinamide phosphoribosyltransferase (NAMPT). NAMPT is a protein involved in the generation of NAD+ in tumor cells, an important mediator of enzymatic reactions involved in various functions of leukemic disease progression. Leukemic blasts show a higher NAD+ turnover rate than normal cells, suggesting that NAD+ biosynthesis could be critically required in hematologic malignancies and therefore targeting the regeneration of NAD+ offers an attractive alternative strategy in AML. Inhibitors of NAMPT that have been described by others have shown potent anti-tumor activity and selectivity of several tumor models, including AML, while preserving the viability and functionality of normal tissues. While two agents targeting NAMPT have been tested in Phase I clinical trials, dose-limiting toxicities including thrombocytopenia and gastrointestinal toxicities led to their clinical discontinuation. Novel compounds with improved tolerability are needed. We sought to determine the mechanism of anti-tumor activity on AML leukemic cell population using a novel compound, KPT-9274, targeting NAMPT. We will also highlight several mechanisms used to antagonize AML disease progression v (open full item for complete abstract)

Committee: John Byrd (Advisor); Rosa Lapalombella (Advisor); Sameek Roychowdhury (Committee Chair); Vinay Puduvalli (Committee Member) Subjects: Biomedical Research; Oncology; Pharmacology

Doctor of Philosophy, Case Western Reserve University, 2019, Epidemiology and Biostatistics

Oncology clinical trials generate the evidence required to obtain regulatory approval for new interventions; the life-saving treatments cancer patients receive today, and the novel therapies that will transform future care paths, rely on data from clinical trials. Unfortunately, the therapeutic advances driven by clinical research are limited to the patient populations that best represent those enrolled in clinical trials. The explicit driver of this limited generalizability is the design of clinical trial eligibility criteria. Although overly restrictive eligibility criteria have been critiqued in the literature, quantitative studies evaluating the appropriateness of these criteria have not been performed. Therefore, we analyzed the eligibility criteria of a particular oncology disease group (hematologic malignancies), specifically exploring: 1) the relationship between commonly used organ function eligibility criteria and the expected toxicities of the trials' interventions, 2) reasons for ineligibility and the outcomes of leukemia patients eligible vs. ineligible for South Western Oncology Group (SWOG) trials, and 3) the health policy implications of overly restrictive eligibility criteria. Collectively, the findings of these studies suggest that the eligibility criteria for hematologic malignancy clinical trials are overly restrictive; the organ function criteria fail to reflect the expected toxicities of the trials' interventions / observed adverse events and the administrative criteria associated with the timing of screening tests / sample submissions included in SWOG leukemia protocols are too conservative. Furthermore, our results demonstrated the safety and efficacy outcomes were comparable between the leukemia/myelodysplastic syndrome patients ineligible for administrative or non-clinically significant reasons and the patients fully meeting the eligibility criteria. These findings suggest, patients who may benefit from potentially life-saving treatmen (open full item for complete abstract)

Committee: Siran Koroukian PhD (Advisor); Dana Crawford PhD (Committee Chair); J.B. Silvers PhD (Committee Member); Mikkael Sekeres MD, MS (Committee Member) Subjects: Design; Health Care; Health Sciences; Medicine; Oncology; Public Policy

Doctor of Philosophy, Case Western Reserve University, 2016, Pathology

Inositol 1,4,5-trisphosphate receptors (IP3Rs) are channels located on the endoplasmic reticulum (ER) that release calcium (Ca2+) ions into the cytosol during intracellular signaling cascades. By initiating and shaping Ca2+ signals, IP3Rs play key roles in many essential processes. Consequently, cells have evolved complex mechanisms to control IP3R-mediated Ca2+ signals, including regulation by interacting proteins. In this dissertation, the regulation of IP3Rs by interacting proteins was investigated in order to: (1) further establish the identities and roles of IP3R-interacting proteins in controlling Ca2+ release and cell survival; and, (2) evaluate the possibility of targeting protein-IP3R interactions for the treatment of cancers. Reported herein is the discovery that the glycolytic enzyme pyruvate kinase M2 (PKM2) localizes in part to the ER and interacts with IP3Rs. By controlling IP3R-mediated Ca2+ release, IP3R-associated PKM2 governs Ca2+ transfer from ER to mitochondria, regulating cellular bioenergetics and suppressing Ca2+ signals capable of inducing cell death. The control of Ca2+ homeostasis by PKM2 is thus a novel mechanism by which PKM2 promotes cell survival. Notably, these findings suggest that PKM2 serves as a gatekeeper of the metabolic flux of pyruvate between oxidative metabolism in mitochondria versus fermentation to lactate in the cytoplasm, a novel regulatory function of PKM2 that may be especially important in promoting aerobic glycolysis (Warburg effect) in cancer cells. Also presented here is a study assessing the potential of targeting the interaction of the anti-apoptotic protein Bcl-2 with IP3Rs as a novel therapeutic approach for cancer. Bcl-2 inhibits pro-apoptotic Ca2+ release through interaction with IP3Rs via its BH4 domain, but this effect can be reversed by BIRD-2, a synthetic peptide inhibitor of Bcl-2-IP3R interaction, which induces selective apoptosis in malignant cells. The study demonstrates that BIRD-2 is an effective an (open full item for complete abstract)

Committee: Clark Distelhorst (Advisor) Subjects: Biochemistry; Biology; Biomedical Research; Cellular Biology; Molecular Biology; Pathology