6-Shogaol induces apoptosis in transformed and primary leukemia cells. Cells apoptosis was determined using Annexin V/PI staining by flow cytometry. The values obtained from Annexin V/PI represent the mean±SD for three separate experiments. The difference were significant at *p < 0.05, **p < 0.01. (a) Jurkat cells were treated without or with various concentrations of 6-shogaol (6S) for 24 h. (b) Jurkat cells were treated without or with 15 μM for different time intervals as indicated. (c) Jurkat cell were treated without or with 6S for various concentrations or time intervals as indicated, total cellular extracts were prepared and subjected to western blot assay using antibodies against PARP, cleaved-caspase 3 (C-Caspase 3) and cleaved-caspase 7 (C-Caspase 7). (d and e) Jurkat, U937, and HL-60 cells were treated without or with 15 μM for 24 h, after which apoptosis was determined by flow cytometry. Total cellular extracts of protein were prepared and subjected to western blot using antibodies as indicated. (f) Mononuclear cells were isolated from the peripheral blood of 7 patients with leukemia (designated as P1–7), including 4 AML, 1 MM (P7), and 2 CLL patients (P3 and P4). Cells were then treated without or with 10 and 20 μM 6S for 24 hours. (g) Mononuclear cells were isolated from the peripheral blood of 5 healthy donors and incubated with 0, 10 and 20 μM of 6S for 24 hours.