{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"Friend leukemia integration 1 (Fli-1) is a member of the ETS family of DNA binding transcription factors. Fli-1 is involved in cellular proliferation and tumorigenesis. Among normal tissues, endothelial cells and small lymphocytes express Fli-1. According to literature, Fli-1 is expressed in the great majority of vascular tumors including angiosarcomas, hemangioendotheliomas, hemangiomas, and Kaposi’s sarcomas. Approximately 90% of Ewing’s sarcoma/primitive neuroectodermal tumors (ES/PNET) have a translocation mutation, t(11;22)(q24;q12), which results in fusion of EWS to Fli-1, and production of an EWS-Fli-1 fusion protein."}]}]}