HMGA2 and acute lymphoblastic leukemia: The T-ALL neoplastic cells are actively proliferating.17 The majority (67±9.4%, n=5) of splenic T cells from HMGA2 transgenic animals but essentially no cells (1.05±0.19%, n=5, P<0.0001) from age-matched wild-type mice exhibited substantial BrdU incorporation (Figures 4a and b), showing that T cells in the transgenic mice were proliferating robustly.