Tipifarnib induces mitochondrial pathway-dependent apoptosis in Jurkat cells. (A-C) Aliquots containing 1 to 2 × 105 Jurkat cells/mL or Jurkat derivatives were incubated for 48 hours with diluent (0.1% DMSO), 1000nM tipifarnib (A; tipibarnib), or the concentration of tipifarnib indicated in panels B and C. At the completion of the incubation, cells were stained with Hoechst 33258 and examined by fluorescence microscopy (A), stained with APC-coupled annexin V and examined for phosphatidylserine externalization (B), or permeabilized with 0.1% Triton X-100 in 0.1% (wt/vol) sodium citrate containing 50 μg/mL propidium iodide and subjected to flow microfluorometry (C). (D) Whole cell lysates were subjected to immunoblotting for the indicated antigens. (E-F) Results obtained when the indicated Jurkat variants were treated for 72 hours with 1000nM tipifarnib, for 6 hours with 25 ng/mL CH.11 agonistic anti-Fas antibody, or for 24 hours with 2μM etoposide (E) or with varying tipifarnib concentrations (F) and analyzed as indicated in panel C. Errors bars in panel E indicate mean ± SD of 3 independent experiments.
