Apoptosis in HAP1 Cells Induced by L-Asparaginase

*+pRS and *+pRS-shHAP1 cells (1×10⁴) seeded on 96-well plates coated with 0.2 mg/ml poly-L-ornithine and pre-treated with RuR (3 μM), CsA (1 μM) or Mito-Tempo (5 μM) for 30 min then stimulated with 100 mIU L-asparaginase for 12 h were stained with Hoechst 34580 and FITC-Annexin V. FITC-positive apoptotic cells were counted 12 h post-treatment at ×10 magnification using a I×71 Olympus inverted microscope attached to a 37°C incubator with 5% CO₂. The percentage of FITC-positive apoptotic cells was determined from a field of ∼100 Hoechst 34580-stained cells using the Olympus CellSens software (Olympus, Japan).