Figure 4.

Synergistic cell death was partially mediated by activation of the JNK pathway. (A) Mean fluorescence intensity of flow cytometric analysis of c-Jun phosphorylated Ser⁷³ in ALL cell lines treated with cytotoxic agents with or without the addition of 16 μM RAD001. *P<0.05 compared to cells treated with RAD001 or vincristine as single agents. (B) NALM6, REH and LK63 cells were untreated or exposed to 0.6 nM vincristine or 100 nM etoposide with or without the addition of 16 μM RAD001 in the absence or presence of 5 μM SP600125 for 24 h. Cells were analyzed by flow cytometry and cells lacking annexin V and 7-AAD staining were considered viable. The mean±SD of triplicate determinations is shown. ^†Indicates a significant synergistic interaction between the chemotherapeutic agent and RAD001 (P<0.05) *Indicates a significant reversal of the synergistic interaction by SP600125 (P<0.05).