Molecular and cytological features of the mouse B-cell lymphoma line iMyc-^Eμ-1

Background: Myc-induced lymphoblastic B-cell lymphoma (LBL) in iMyc^Eμ mice may provide a model system for the study of the mechanism by which human MYC facilitates the initiation and progression of B cell and plasma cell neoplasms in human beings. We have recently shown that gene-targeted iMyc^Eμ mice that carry a His₆-tagged mouse Myc cDNA, Myc^His, just 5′ of the immunoglobulin heavy-chain enhancer, Eμ, are prone to B cell and plasma cell tumors. The predominant tumor (∼50%) that arose in the iMyc^Eμ mice on the mixed genetic background of segregating C57BL/6 and 129/SvJ alleles was LBL. The purpose of this study was to establish and characterize a cell line, designated iMyc^Eμ-1, for the in-depth evaluation of LBL in vitro. Methods: The morphological features and the surface marker expression profile of the iMyc^Eμ-1 cells were evaluated using cytological methods and FACS, respectively. The cytogenetic make-up of the iMyc^Eμ-1 cells was assessed by spectral karyotyping (SKY). The expression of the inserted Myc^His gene was determined using RT-PCR and qPCR. Clonotypic immunoglobulin gene arrangements were detected by Southern blotting. The global gene expression program of the iMyc^Eμ-1 cells and the expression of 768 "pathway" genes were determined with the help of the Mouse Lymphochip