Kasumi-1 and HL-60 cells infected with lentivirus containing either ConshRNA (Con) or SurshRNA (S3, S4, and S5) for 24 hr were then untreated or treated with etoposide (Kasumi-1: 2.5μmol/L; HL-60: 0.4μmol/L) for additional 24 hr. Cells were collected and subjected to Western blot analyses of survivin, Bcl-2, Bcl-xL, caspase-8, caspase- 3, PARP, γH2A.X (Ser139), H2A.X, P-CHK2 (Thr68), CHK2, or β-actin (A), or a specific apoptosis ELISA (B). Bars, SD.