2ME2 inhibits cell growth of STI571-sensitive and -resistant cells. STI571-sensitive (BCR-ABL) or STI571-resistant (BCR-ABL-S) Ba/F3 cells transformed by BCR-ABL (A) and Ba/F3 cell lines transformed by tyrosine kinase oncogenes (B-C) were used. (A) Cells were treated with the indicated amounts of 2ME2 in combination with either STI571 (STI571-sensitive cells, left panel) (0.5 μM; ▪) or the solvent DMSO (♦) as indicated. (B) Cell growth also was determined in a 72-hour culture in response to 2ME2 (5 μM, right panel) or the solvent DMSO (left panel) as indicated. (C) Induction of caspase-3 activity (typical experiments, n = 3, left panel) and annexin V—positive cell staining (n = 2, right panel) was measured after 24 hours of treatment with 2ME2 (5 μM) or E2 (5 μM) and compared to cells treated with DMSO. Values represent means ± SEM.