Abstract 2123: Novel integration sites for Friend murine leukemia virus

Abstract

Abstract Background: Friend murine leukemia virus (F-MuLV), a type C retrovirus, induces erythroleukemia when injected into certain strains of mice. The Induction of erythroleukemia is associated with viral integration into Friend leukemia integration site-1 (Fli-1). In some F-MuLV-infected mice we did not observe viral integration into Fli-1 region by Southern blot analysis. We hypothesize that induction of leukemia in these mice is due to insertion of F-MuLV into a novel integration site distinct from Fli-1. Methods: The genomic DNA of F-MuLV-induced leukemic cells is digested by StuI restriction enzyme. DNA sequences of about 50 base pairs in length, termed adaptors, are then ligated to both ends of the digested fragments. Using primers for the adaptors and F-MuLV sequences, we performed PCR, followed by nested PCR to amplify those fragments that contain F-MuLV sequence. The PCR product is gel purified, cloned into a TA vector and sequenced. The sequences are compared to mouse genome databank to determine the F-MuLV flanking sequences. Results: We identified seven novel integration sites for F-MuLV. Three of these sites are located inside genes and the remaining four do not interrupt any genes. We performed PCR to check if any of these integration sites were also targets of F-MuLV in twenty other tumors of the same type. We found that one of these integration sites which is close to Myb gene occurred in twenty five percent of the tested tumors in an area 1 kb in length. Conclusion: We identified seven novel F-MuLV integration sites for F-MuLV. We showed that the integration site on chromosome 10 close to the Myb gene occurs in 25% of F-MuLV- induced tumors and is therefore a common integration site. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2123.