Meningioma is one of the most commonly diagnosed intracranial tumors in dogs and humans. Treatment failures resulting in local recurrence and death remain common in tumors of high grade, prompting a need for additional therapeutic options that are both effective and affordable. Genetic modification of the LaSota strain of Newcastle Disease Virus (rLAS) has allowed the virus' fusion protein cleavage site to be replaced with that belonging to urokinase plasminogen activator (rLAS-uPA). This site is cleavable exclusively by the uPA receptor (uPAR), which is overexpressed in canine meningioma. The rLAS-uPA represents a targeted therapy that has the potential to be efficacious against meningioma when administered systemically. A Phase I clinical trial was designed to evaluate the safety and preliminary efficacy of rLAS-uPA administered to dogs with presumptive intracranial meningioma. The primary endpoint was to define the safety of rLAS-uPA, as determined by serial clinical and laboratory assessments during and after viral administration, using standard toxicity metrics defined by the Veterinary Cooperative Oncology Group (VCOG). Secondary end-points included anti-tumor activity quantified by magnetic resonance imaging (MRI) assessment of tumor size, and characterization of immune responses to the rLAS-uPA. Four dogs completed the trial without significant toxicity. No objective tumor responses were noted on MRI from any dog. All dogs produced antiviral antibodies and increased circulating cytokines during the course of treatment. No virus was recovered from plasma, urine, or cerebrospinal fluid. These results indicate that further investigation into the rLAS-uPA dose intensity and interval are required to further develop this therapy. / Master of Science / The use of a modified Newcastle Disease Virus intravenous infusion to treat brain tumors in dogs has been shown to have no overt significant adverse effects. However, further investigation is required to determine the efficacy and optimal dosing protocol for this potential treatment.

Non-small cell lung cancers (NSCLC) constitute 80-85% of lung cancers and are the leading cause of cancer-related deaths globally. The most common cause is prolonged smoking. Current treatment options for NSCLC include surgery, radiation, chemotherapy, targeted drug therapy, and immunotherapy. Although these medications are effective in the short term, patients often face issues of drug resistance and debilitating side effects with prolonged use. Currently, the use of Zika virus (ZIKV) is being researched as a possible alternative treatment for cancer, which minimizes side effects and the risk of drug resistance. TIM/TAM proteins are identified as the putative ZIKV receptors on the surface of human cells that mediate viral entry through apoptotic mimicry. Once engulfed, the virus can hijack the host cell’s machinery to replicate and propagate the infection. Previous research has shown the potential of using Zika virus as an oncolytic agent in glioblastoma and neuroblastoma cell lines. The success of Zika-induced oncolysis in these cancers opens doors for expanding into other cancers, including NSCLC. Infection of six diverse NSCLC cell lines with ZIKV revealed that three cell lines were sensitive to ZIKV-induced oncolysis while the remaining were resistant. Transcriptome data analysis of TIM/TAM and CD24 mRNA expression levels were compared between ZIKV-sensitive and resistant cell lines, revealing AXL and TIM-1 as potential players in increasing or decreasing ZIKV infection. High AXL (TAM) expression correlated with increased sensitivity to ZIKV, while high TIM-1 (TIM) expression correlated with increased resistance. Experiments with AXL silencing in ZIKV-sensitive cell lines provided evidence of the role of AXL in increasing ZIKV sensitivity. Although further studies with TIM-1 must be done to determine its role in conferring resistance, AXL and TIM-1 have the potential to be biomarkers in predicting tumor sensitivity to ZIKV-induced oncolytic therapy.