Figure 1.

The combination of mitomycin C and rapamycin induced synergistic cytotoxicity and apoptosis. LS174T (a) and LS180 (b) cells were treated with mitomycin C (5 μg/ml) and/or rapamycin (2.5–10 μg/ml) for 24 h. Cell viability was analyzed by MTS assay. Error bars represent S.D. from triplicate experiments. The asterisk (**) represents a statistically significant difference compared with the control group (P<0.01). (c) LS174T cells were treated with mitomycin C (5 μg/ml) and/or rapamycin (2.5–10 μg/ml) for 24 h and cells were stained with fluorescein isothiocyanate (FITC)-Annexin V and propidium iodide (PI). Apoptosis was detected by the flow cytometric assay. After treatment, the cleavage of caspase 8, caspase 9, caspase 3, or PARP was detected by immunoblotting in LS174T (d) and LS180 (e) cells. Actin was used to confirm the equal amount of proteins loaded in each lane