The Role of Fli-1 in Normal Cell Function and Malignant Transformation

Aberrant expression of the Fli-1 transcription factor following genetic mutation has been recognized as a seminal event in the initiation of certain types of malignant transformation. Indeed, the etiology of a number of virally induced leukemias, including Friend virus-induced erythroleukemia, has been associated with Fli-1 overexpression. The clinical relevance of Fli-1 becomes apparent in human Ewing's sarcoma in which Fli-1 is the target of a characteristic chromosomal translocation. As such, Fli-1 has generated considerable interest over the past several years for its role in malignant transformation and tumor progression. This review will present a synopsis of the current research on Fli-1 with emphasis on its function in malignant transformation. Moreover, the possible role of Fli-1 in cellular proliferation, differentiation and survival, as well as the recent development of transgenic and knock-out mice to investigate the function of Fli-1 will be discussed. Finally, the significance of identifying target genes that are regulated by Fli-1 and their role in cellular function will be reviewed.