Fig. 6
Memantine potentiates cell death of patients’ myeloid leukemic blasts. a Bone marrow (BM) cells of AML patients were analysed for surface expression of Kv1.3 by flow cytometry. Histograms show Kv1.3 profiles of viable CD117+ leukemic blasts cultured for 3 or 24 h and are representative for eight BM samples. Cells without Kv1.3 staining are depicted in grey histograms. b. and c. BM cells of 10 AML patients (Additional file 1: Table S1) were cultured without any drug, with memantine alone (100 μM lower left graph, 50 μM lower right graph), with 1 μM and 2 μM AraC alone, and with AraC plus memantine for 48 h. Cell death was determined with SYTOX/Annexin-V staining and flow cytometry. SYTOX−Annexin-V− cells were considered as viable cells. For each patient, cell viability of untreated (control) AML cells was set as 100% and cell viability of treated AML cells was related to the corresponding control sample. b The graphs show data of two representative patients (cells were treated with 100 μM memantine). c Graphs provide the relative cell viability of BM cells of 10 AML patients. Coefficient of drug interaction (CDI) values for combined memantine and AraC treatments are provided in the boxes; CDI < 1 indicates synergism and CD > 1 antagonism