Integrated Multimodal Analysis: Evaluating the Impacts of Chemotherapy and Electroporation-Based Therapy on Lymphatic and Blood Microvasculature in Cancer

The lymphatic and blood vascular systems are two important vessel networks that serve different roles in healthy states and in cancer. In breast cancer the most common cancer amongst women, mortality remains high despite increased treatment response due to metastatic spread, preferentially through the lymphatics. One aggressive subtype, triple negative breast cancer (TNBC) contributing to 15 to 30 percent of cases and is characterized by the absence of expression of three therapeutic biomarkers. As targeted therapy is limited, treatment relies on standard of care via surgery, radiotherapy, and chemotherapy with limited efficacy and increase in survival. Chemotherapies negatively alter the lymphatic vasculature benefiting the tumor, through lymphangiogenesis. This dissertation seeks to understand how the mechanisms of commonly used chemotherapeutics, like carboplatin, and a novel 2nd generation ablative therapy called High Frequency Irreversible Electroporation (H-FIRE), which utilizes electric pulses to ablate tumor cells, affect the lymphatic and blood microvasculature in the tumor, surrounding fat pad, tumor draining lymph node (TDLN) using multiple analysis methods. This occurred through three main methods 1) identification of oxidative stress effects of chemotherapeutic application of carboplatin on lymphatic endothelial cells in vitro, 2) characterization of lymphatic and blood microvascular dynamics in a 4T1 breast cancer mouse model treated with sub-ablative H-FIRE, 3) through the development of a novel habitat imaging method to identify treatment specific changes in the tumor draining lymph node, and the development of a hybrid agent-based model (ABM) to test cancer cell flow mediated invasion in brain cancer. Herin the work showed that carboplatin induced lymphatic phenotypic changes occurred through generation of reactive oxygen species dependent on VEGFR3 and was reversed through treatment with the antioxidant N-acetylcysteine. In the 4T1 model, sub ablation with H-FIRE induced temporal remodeling of the lymphatic and blood vasculature within the viable tumor, in the surrounding fat pad, and in the tumor draining lymph node over seven days, suggesting an optimal time of application of adjuvant therapy. The development of a habitat imaging analysis method to identify TDLN vascular habitats and the perturbation to treatment in a retrospective analysis of prior work. Lastly, the development of a hybrid ABM through the incorporation of experimentally measured fluid flow fields from dynamic contrast enhanced MRI imaging building upon existing work, and showing the usefulness in comparing mechanisms of cancer cell invasion mediated fluid flow. Altogether, this work presents novel insight into the lymphatic system in cancer within various treatments contexts and new methods of quantifying changes due to treatment. Hopefully, these findings can be used to further inform the field towards a more comprehensive understanding of treatment effects in breast cancer.