Flow cytometry analysis of cell apoptosis in kasumi-1 cells with different APP expression. Both the rate of early (Q4-2) and late apoptosis (Q2-2) in si-APP kasumi-1 cell increased significantly when compared with the rate in wild type and NC kasumi-1 cell (Early apoptosis rate: si-APP: 29.00%±0.98%, wild type: 21.43%±0.86%, NC: 21.67%±0.78%, F=71.927, P<0.001; Late apoptosis rate: si-APP: 19.80%±1.51%, wild type: 12.33%±0.75%, NC: 12.90%±1.25%, F=35.239, P<0.001).