GO-203 inhibits cell growth and induces death of BaF3, BaF3/FLT3-ITD, and MOLM-14 cells. BaF3 cells grown in the presence of interleukin-3 (IL-3) were treated with GO-203 at the indicated concentrations for 72 hours (A). BaF3/FLT3-ITD cells were left untreated (open bars) or treated with 2 μM GO-203 (solid bars) for the indicated days (B). Cell number (mean ± standard deviation [SD] of 3 determinations) was determined by trypan blue staining. (C) BaF3/FLT3-ITD cells were treated with the indicated concentrations of GO-203 for 3 days. Percentage cell death (mean ± SD of 3 determinations) was determined by PI staining and flow cytometry. (D) MOLM-14 cells were treated with the indicated concentrations of GO-203 for 3 days. Percentage cell death (mean ± SD of 3 determinations) was determined by PI staining and flow cytometry. (E,F) BALB/c ν/ν mice were injected subcutaneously in the flank with 10⁷ MOLM-14 cells. The mice were pair-matched when the tumors were ∼100 mm³. Treatment groups consisted of 7 mice injected intravenously with PBS (vehicle control; open squares) or 7.5 mg/kg GO-203 (closed squares) each day on days 1-5 and 8-12. Tumor measurements were performed on the indicated days. The results are expressed as tumor volumes (mean ± SE) (D). Percentage survival as determined by Kaplan-Meier analysis (E).