Comparative molecular genetic analysis of lymphomas from six inbred mouse strains

Previous studies of 21 highly lymphomatous AKXD recombinant inbred mouse strains demonstrated correlations between lymphoma type, the somatic proviral DNA content of the lymphoma, and the frequency of virally induced rearrangements in eight common sites of viral integration (Myc, Pim-1, Pvt-1, Mlvi-1, Mlvi-2, Fis-1, Myb, and Evi-1). In this study we analyzed lymphomas from six inbred mouse strains, AKR/J, C58/J, HRS/J (hr/hr and hr/+), SJL/J, SEA/GnJ, and CWD/LeAgl, to determine whether these correlations are also evident in these strains. Mice of the AKR/J, C58/J, and HRS/J strains died exclusively of T-cell lymphomas. In contrast to earlier studies which showed a great disparity in the rate and incidence of lymphomas in HRS/J hr/hr and HRS/J hr/+ mice, we found a high incidence of T-cell lymphomas and the same mean age of onset of disease in both strains. SJL/J mice died primarily of pre-B-cell lymphomas, whereas CWD/LeAgl and SEA/GnJ mice died primarily of B-cell lymphomas. Somatically acquired mink cell focus-forming proviruses were detected only in T-cell lymphomas, whereas ecotropic proviruses were found in lymphomas from all hematopoietic cell lineages. No rearrangements were detected in the Fis-1, Mlvi-2, and Myb loci, whereas rearrangements were detected in the Mlvi-1, Myc, Pim-1, Pvt-1, and Evi-1 loci. Most rearrangements were found in T-cell lymphomas, and many were virally induced. These results are similar to those we obtained previously for lymphomas of 21 highly lymphomatous AKXD recombinant inbred mouse strains.