Ets and retroviruses - transduction and activation of members of the Ets oncogene family in viral oncogenesis

Studies of retroviral-induced oncogenesis in animal systems led to the init ial discovery of viral oncogenes and their cellular homologs, and provided critical insights into their role in the neoplastic process. V-ets, the fou nding member of the ETS oncogene family, was originally identified as part of the fusion oncogene encoded by the avian acute leukemia virus E26 and su bsequent analysis of virus induced leukemias led to the initial isolation o f two other members of the ETS gene family. PU.1 was identified as a target of insertional activation in the majority of tumors induced by the murine Spleen Focus Forming virus (SFFV), while fli-1 proved to be the target of F riend murine leukemia virus (F-MuLV) in F-MuLV induced erythroleukemia, as well as that of the 10A1 and Graffi viruses. The common features of the ery throid and myeloid diseases induced by these viruses provided the initial d emonstration that these and other members of the ETS family play important roles in hematopoietic development as well as disease. This review provides an overview of the role of ETS genes in retrovirally induced neoplasia, th eir possible mechanisms of action, and how these viral studies relate to cu rrent knowledge of the functions of these genes in hematopoiesis.