Identification of a common site of provirus integration in radiation leukemia virus-induced T-cell lymphomas in mice

The BL/VL3 Kaplan radiation leukemia virus (RadLV-VL3) is a nondefective re trovirus that induces T cell lymphomas in several strains of mice. By using DNA probes derived from RadLV/VL3 provirus-flanking sequences cloned from the BL/VL3 cell line, we identified a DNA region rearranged in 5 of 19 tumo rs analysed (25%). All proviruses were integrated in the same 5'-to-3' orie ntation in a small DNA region called Kis1 (Kaplan integration site 1). This region was localized on distal mouse chromosome 2 in a region not previous ly identified as important to lymphomagenesis. The cells rearranged at the Kis1 locus represent a clonal subpopulation of the clonal tumor masses exam ined, indicating a probable role of Kis1 in tumor progression. (C) 1999 Aca demic Press.