Project Summary My work aims to uncover non-genetic mechanisms that drive cancer cell plasticity. I focus specifically on Ewing Sarcoma, a pediatric cancer driven by a single oncogenic fusion, making it prototypical for cancers whose disease progression likely depends on non-genetic adaptations. During my postdoc thus far, I have developed two complimentary models to study heterogeneity of cell states in Ewing Sarcoma: (1) a quantitative high- resolution imaging assay that uses computer-vision based classification of single cell states within Ewing Sarcoma xenografts in zebrafish, and (2) a bimodal distribution of cell signaling states characterized by differential expression and organization of the scaffolding protein Caveolin-1. While the precise role of Caveolin- 1 in cancer remains controversial, recent works suggest that mechanical cues trigger changes in its localization and activity, implicating Caveolin-1 as a potential integrator of environmental cues and cell signaling. However, the mechanism of response and the ensuing signaling cascades remain to be understood, especially in the context of cancer. Therefore, I will leverage the unique experimental frameworks I have established to test whether Cav-1 acts as a plasticity factor promoting tumor cell adaptation in Ewing Sarcoma. This work will reveal mechanisms of fast cellular adaptation to diverse microenvironmental cues which will provide unique insight into the drivers of metastasis and drug resistance. I am eager to build upon the foundations I have established during my postdoc thus far to discover previously unapproachable mechanisms of cell adaptation. As the proposed work requires cross-disciplinary expertise, my continued development in several areas will be instrumental to my progress. Dr. Danuser and the Danuser lab will provide the ideal environment to develop advanced microscopy techniques and skills in computational analysis of 3D data. Dr. Amatruda will provide guidance and support in the use of zebrafish disease models and relevance to pediatric cancer. Dr. Lamaze and Dr. Cobb will provide scientific insight in caveolar biology, MAPK cell signaling, and cancer biology. Combined with the stellar training environment and resources available at UT Southwestern, this provides the ideal environment to carry out this work. The training I will receive will enable me to lead an independent laboratory that studies cancer cell plasticity in a variety of experimental models, with specific focus on imaging-based approaches and physiologically relevant environments.