Figure 6

Inhibition of AKT1, but not of mTORC1 induces apoptosis in imatinib-resistant cell lines. Apoptosis was assessed by Annexin-V staining. Experiments were performed in triplicates. Cell lines were treated for 24 h with A) imatinib (1 μM), rapamycin (10 nM), or a combination of both agents. Note that rapamycin did not induce apoptosis and did not sensitize resistant cells to imatinib. Additional experiments showed that preincubation with rapamycin did not sensitize resistant cells, as well. B) Imatinib (1 μM), Akt inhibitor IV (1 μM), or both agents were applied for 24 h; additional experiments showed that 1 μM Akt inhibitor IV induced apoptosis also in cell lines BV-173 (imatinib-sensitive) and NALM-1 (imatinib-resistant).