EWS/FLI 1 Type 4

**Semantic type:** Nucleic Acid, Nucleoside, or Nucleotide|Pharmacologic Substance

**Definition:** The type 4 form of EWS/FLI-1, an oncogenic fusion gene found in Ewing's sarcoma and primitive neuro-ectodermal tumor (PNET). Resulting from a t(11;22) chromosomal translocation, EWS/FLI 1 appears to play an integral role in the development of Ewing's sarcoma and PNET; the type 4 form of this gene has been shown to transform non-neoplastic cells. EWS/FLI 1 type 4 represents a potential target for antisense oligonucleotide therapy of Ewing's sarcoma and PNET. (NCI04)