Fig. 1.
Fig. 1. MEK inhibition potentiates HA14-1 cytotoxicity and apoptosis in AML cell lines with constitutive MAPK activation. / (A) OCI-AML3 cells were cultured under standard conditions or in serum-free medium for 48 hours prior to exposure to PD184352 (10 μM) or vehicle control for 1 hour at 37°C. KG1 cells were pretreated with PD184352 (10 μM) or vehicle control for 1 hour at 37°C prior to exposure to phorbol myristate acetate (60 ng/mL) for 1 hour. Cells were then subjected to Western blot analysis for phosphorylated or total MAPK. Results from one experiment representative of 3 performed are shown. (B) The indicated AML cell lines were seeded at a starting concentration of 2 × 105 cells per milliliter and cultured in the presence of vehicle control (■), 1.25 μM PD184352 (), 12.5 μM HA14-1 (), or a combination of PD184352 and HA14-1 (▪). Vehicle control and PD184352-treated cells were also exposed to 12.5 μM of an inactive compound structurally related to HA14-1. After 48 hours, viable cells were counted by trypan blue exclusion. Results are expressed as a percentage of the viable cells in the vehicle control-treated group and represent the average ± SD of 4 independent experiments. (C) OCI-AML3 cells were seeded at a starting concentration of 2 × 105cells per milliliter and cultured in the presence of vehicle control (○), 1.25 μM PD184352 (●), 12.5 μM HA14-1 (■), or a combination of PD184352 and HA14-1 (▪). Vehicle control and PD184352-treated cells were also exposed to 12.5 μM of an inactive compound structurally related to HA14-1. At the indicated times, ΔΨm was assessed by flow cytometry. Results represent the average of triplicate measurements (10 000 total events for each measurement) and are expressed as percentage of cells with low ΔΨm. SE was constantly less than 2% and is therefore omitted for clarity. Comparable results were obtained in 2 other independent experiments. (D) OCI-AML3 cells were cultured as described above. At the indicated times, caspase activation was assessed by flow cytometry. Results represent the average of triplicate measurements (10 000 total events for each measurement) and are expressed as the percentage of active caspase-positive cells. SE was constantly less than 2% and is therefore omitted for clarity. Comparable results were obtained in 2 other independent experiments.

MEK inhibition potentiates HA14-1 cytotoxicity and apoptosis in AML cell lines with constitutive MAPK activation.

(A) OCI-AML3 cells were cultured under standard conditions or in serum-free medium for 48 hours prior to exposure to PD184352 (10 μM) or vehicle control for 1 hour at 37°C. KG1 cells were pretreated with PD184352 (10 μM) or vehicle control for 1 hour at 37°C prior to exposure to phorbol myristate acetate (60 ng/mL) for 1 hour. Cells were then subjected to Western blot analysis for phosphorylated or total MAPK. Results from one experiment representative of 3 performed are shown. (B) The indicated AML cell lines were seeded at a starting concentration of 2 × 105 cells per milliliter and cultured in the presence of vehicle control (■), 1.25 μM PD184352 (), 12.5 μM HA14-1 (), or a combination of PD184352 and HA14-1 (▪). Vehicle control and PD184352-treated cells were also exposed to 12.5 μM of an inactive compound structurally related to HA14-1. After 48 hours, viable cells were counted by trypan blue exclusion. Results are expressed as a percentage of the viable cells in the vehicle control-treated group and represent the average ± SD of 4 independent experiments. (C) OCI-AML3 cells were seeded at a starting concentration of 2 × 105cells per milliliter and cultured in the presence of vehicle control (○), 1.25 μM PD184352 (●), 12.5 μM HA14-1 (■), or a combination of PD184352 and HA14-1 (▪). Vehicle control and PD184352-treated cells were also exposed to 12.5 μM of an inactive compound structurally related to HA14-1. At the indicated times, ΔΨm was assessed by flow cytometry. Results represent the average of triplicate measurements (10 000 total events for each measurement) and are expressed as percentage of cells with low ΔΨm. SE was constantly less than 2% and is therefore omitted for clarity. Comparable results were obtained in 2 other independent experiments. (D) OCI-AML3 cells were cultured as described above. At the indicated times, caspase activation was assessed by flow cytometry. Results represent the average of triplicate measurements (10 000 total events for each measurement) and are expressed as the percentage of active caspase-positive cells. SE was constantly less than 2% and is therefore omitted for clarity. Comparable results were obtained in 2 other independent experiments.

Close Modal
This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal