![Figure 7. Lovastatin treatment results in collapse of the mitochondrial transmembrane potential, APO2.7 staining, release of cytochrome c into the cytosol, and caspase-3 activation by depletion of GGPP. (A) RPMI 8226 cells were treated for 4 days with solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM). Collapse of the mitochondrial transmembrane potential was determined by staining the cells with DiOC6[3]. The fraction of cells with low (DiOC6[3]low) and the fraction of cells with intact (DiOC6[3]high) mitochondrial transmembrane potential are indicated in gates M1 and M2, respectively. APO2.7 staining was determined by flow cytometry in digitonin-permeabilized cells. The fraction of cells staining with APO2.7-PE (M2) and the fraction of cells not staining with APO2.7-PE (M1) are indicated. Results are representative of 3 experiments performed in triplicate (B) RPMI 8226 cells were treated for 4 days with solvent control or different concentrations of lovastatin (5, 10, 30, 50, 100, 150 μM) alone (▪) or in combination with mevalonate (100 μM; ○), FOH (10 μM; □), or GGOH (10 μM; •). Collapse of the mitochondrial transmembrane potential was determined by staining the cells with DiOC6[3]. Shown is the percentage of cells with low mitochondrial transmembrane potential (gate M1). APO2.7 staining was determined by flow cytometry in digitonin-permeabilized cells. Shown is the percentage of cells staining with APO2.7-PE (gate M2). Experiments were performed 3 times in triplicate. Data are presented as mean ± SEM. (C) RPMI 8226 cells were exposed to solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM) for 2 days, at which time the cells were harvested and cytochrome c in the cytosolic fraction was determined by ELISA. Experiments were performed 3 times in duplicate. Data are presented as mean ± SEM. (D) RPMI 8226 cells were exposed to solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM) for 2 days, at which time the cells were harvested and caspase-3 activation was assessed as described in “Materials and methods.” Experiments were performed 3 times in duplicate. Data are presented as mean ± SEM.](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/102/9/10.1182_blood-2003-03-0970/6/h82135137007.jpeg?Expires=1735570751&Signature=CPt1IE~mVqzoBjQ4Cq920f6PYoEW1eKumoz3oY-xnpGjV35AflXomz3RskhxEHwlLqyZNcgswR3mc-D-a72NPVdFm3FS4lr5B0MRrBGPI-pk~sFdhZAguiaX5fArbo2nSrG-TWZztQJn6X22xDaJb73ToJnPbpXSaljhNgYr6utYdp05Y1n5Z-BsDscK8kVZxP4y9HzKBuHun57Cm14AsRJCH4wwuOO75S3k6uSUwKVsehkIc0Imo4P6laysYwrMRtz3VwaAIsPBKTRMBV~J4D0xqbhx4Jcbbk7djM~PaXhRPCQVr8I5tiOyXi2Ol6H6MwK~-03Xp9C0cY1PJUTYxQ__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Lovastatin treatment results in collapse of the mitochondrial transmembrane potential, APO2.7 staining, release of cytochromecinto the cytosol, and caspase-3 activation by depletion of GGPP. (A) RPMI 8226 cells were treated for 4 days with solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM). Collapse of the mitochondrial transmembrane potential was determined by staining the cells with DiOC6[3]. The fraction of cells with low (DiOC6[3]low) and the fraction of cells with intact (DiOC6[3]high) mitochondrial transmembrane potential are indicated in gates M1 and M2, respectively. APO2.7 staining was determined by flow cytometry in digitonin-permeabilized cells. The fraction of cells staining with APO2.7-PE (M2) and the fraction of cells not staining with APO2.7-PE (M1) are indicated. Results are representative of 3 experiments performed in triplicate (B) RPMI 8226 cells were treated for 4 days with solvent control or different concentrations of lovastatin (5, 10, 30, 50, 100, 150 μM) alone (▪) or in combination with mevalonate (100 μM; ○), FOH (10 μM; □), or GGOH (10 μM; •). Collapse of the mitochondrial transmembrane potential was determined by staining the cells with DiOC6[3]. Shown is the percentage of cells with low mitochondrial transmembrane potential (gate M1). APO2.7 staining was determined by flow cytometry in digitonin-permeabilized cells. Shown is the percentage of cells staining with APO2.7-PE (gate M2). Experiments were performed 3 times in triplicate. Data are presented as mean ± SEM. (C) RPMI 8226 cells were exposed to solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM) for 2 days, at which time the cells were harvested and cytochrome c in the cytosolic fraction was determined by ELISA. Experiments were performed 3 times in duplicate. Data are presented as mean ± SEM. (D) RPMI 8226 cells were exposed to solvent control or lovastatin (30 μM) alone or in combination with mevalonate (meva; 100 μM), FOH (10 μM), or GGOH (10 μM) for 2 days, at which time the cells were harvested and caspase-3 activation was assessed as described in “Materials and methods.” Experiments were performed 3 times in duplicate. Data are presented as mean ± SEM.
