Figure 4. Prior irradiation differentially alters the adaptive landscape for different oncogenes.

Mice were left untreated (-) or irradiated with 5 Gy (+). Six weeks later, mice were sacrificed, and BM was isolated and transduced with MiG vector or MiG expressing p185-Bcr-Abl, activated Akt, c-Myc, N-Ras12D or ICN, and immediately transplanted into lethally irradiated recipients (5×10⁶ cells/mouse). Initial transduction efficiencies were determined after 3 days of culture under HSC conditions: V (3.80%, 5.08%), Bcr-Abl (0.2, 0.2), Myc (7.77%, 12.43%), Akt (2.25, 2.79), Ras (1.76, 3.48) and ICN (0.92, 1.05), for unirradiated and irradiated BM cells, respectively. At 1 month post transplantation, GFP expression was determined within peripheral blood MAC1⁺ and B220⁺ cells, as well as within total nucleated blood cells.