FIG. 8.

Overexpression of Gfi-1B renders K562 cells susceptible to As₂O₃-induced apoptosis. K562 cells were transfected with pCMV2-Flag-Gfi-1B or an empty vector. (A) After 24 h, total lysates were subjected to Western blot analysis using anti-Gfi-1B and β-tubulin antibodies (Ab). −, absent; +, present. (B) Transfected cells were also treated with or without As₂O₃ (0.5 μM) as indicated for an additional 48 h. For comparison, a parallel set of cells transfected with an empty vector was treated with imatinib (1 μM) in the presence or absence of As₂O₃ (0.5 μM). Cells were then harvested for annexin V-FITC and propidium iodide staining prior to flow cytometric analysis.