FLI1 and Ewing sarcoma: Ewing's sarcoma is a disease that appears to be etiologically driven by a few primary genetic abnormalities involving a fusion of an EWS family member with a transcription factor, of which the commonly fused transcription factor partner is FLI1. Therefore, these tumors offer a relatively homogenous model system for the identification of specific contextual vulnerabilities that could be targeted with novel therapeutic strategies.