Friend Leukemia Virus Integration Research Articles

Pelvic primitive neuroectodermal tumor associated with a cluster of small round cell tumors: case report and review of current literature☆

Background Peripheral primitive neuroectodermal tumor (pPNET) is aggressive and rare, comprising 1% of soft tissue sarcomas. Involvement of the reproductive tract is unusual. Case A 35-year-old woman had a pelvic mass and omental cake. Frozen-section examination at laparotomy revealed small round cell tumor confirmed as pPNET. Chemotherapy with vincristine, doxorubicin, and cyclophosphamide alternating with ifosfamide and etoposide with mesna yielded complete response. The patient's mother died of a similar tumor at age 52 years, and the patient's husband had adult Ewing sarcoma, constituting an unusual cluster of related tumors. Conclusions Genetic recombination resulting in a chimeric transcript of the Ewing sarcoma gene and the Friend leukemia virus integration site is characteristic of these tumors. Surgical resection and multiagent chemotherapy may enhance survival.

Cloning of the entire FL11 gene, disrupted by the Ewing’s Sarcoma translocation breakpoint on 11q24, in a yeast artificial chromosome

FLI1 (Friend leukemia virus integration 1), a member of the Ets gene family, is disrupted on 11q24 by the Ewing's Sarcoma (ES) and Peripheral Neuroepithelioma (PNE) t(11;22)(q24;q12) translocation. ES and PNE are Primitive Neuroectodermal Tumors (PNETs) and the consistent translocation t(11;22)(q24;q12) can be used for differential diagnosis. In PNETs the 3' part of human FLI1 is translocated from 11q24 to 22q12, where it is juxtaposed to the 5' end of the Ewing's Sarcoma gene (EWS). A fusion transcript, resulting in a chimeric protein, is generated. Here, we present the isolation and detailed characterization of a 250-kb colinear YAC, B45C11, which encompasses the ES and PNE breakpoint on 11q24, as shown by FISSH on ES and PNE chromosomes and interphase nuclei. This YAC represents a new reagent for potential use in rapid differential diagnosis by FISSH on tumor biopsies and on paraffin embedded samples, particularly when DNA and/or RNA are not available for molecular analysis. YAC B45C11, which spans 250 kb of contiguous DNA around the ES and PNE breakpoint, contains the entire FLI1 gene. Three potential HpaII-tiny-fragment (HTF) islands are revealed within the YAC. One of these islands appears to be associated with the 5' end of FLI1, which extends over approximately 120 kb of DNA on 11q24. In addition, we demonstrate that YAC B45C11 contains other transcribed sequences in addition to FLI1, by "cross-species" Northern blot hybridizations, which suggests the presence of additional genes in the immediate vicinity of the ES breakpoint on 11q24.