IGF1 and acute lymphoblastic leukemia: In order to investigate the potential efficacy of IGF signaling inhibitors in human T-ALL, we tested two clinical grade IGF1R inhibitors, a humanized monoclonal blocking antibody, CP-751,871[24], and a small molecule tyrosine kinase inhibitor (TKI) with activity against both IGF1R and InsR, BMS-754807[25], against a broad panel of 27 human T-ALL cell lines.