FLI1 and neoplasm: Because several recent reports have demonstrated that EWS-FLI1 expression level greatly influences Ewing sarcoma tumor cell behavior [13, 14, 16], and that EWS-FLI1 expression level within individual tumor cells is highly variable [14], we sought to examine how tumor cell EWS-FLI1 level impacts the response to and interaction with T-cells.