Fig. 2

tnFGFR1 promotes leukemia development with a stem cell immunophenotype. Representative flow cytometric profiles of the bone marrow cells from the mice transplanted with various derivative constructs of the BCR-FGFR1 kinase (A) at the time of sacrifice show extensive GFP-positive cells in all cases, demonstrating leukemic development compared with the MIG control which are GFP-negative (normal) cells. Analysis of cell lineage-specific markers demonstrates low levels (< 10%) of T-cell (CD8/CD4) and myeloid (Mac1/Gr1) markers but high-level presence of the B220 B-cell marker in cells transduced with the full length chimeric kinases as well as the tnFGFR1 transduced cells. Analysis of stem cell markers KIT and SCA1, however, indicate that while the BCR-FGFR1 kinases and its mutant derivative are mostly negative, the cells from the tnFGFR1 transduced mice predominantly express KIT with a small subgroup also expressing SCA1. Quantitative scatter plots for each marker in each individual mouse within the subgroups (N = 5) compared with the MIG transfected control cells are shown in (B). ns = not significant. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001.. These values represent pairwise comparison between individual oncogenic chimeric kinases and the normal MIG group in each case