24-hourcytotoxicity of α-bisabolol in primary blasts from 42 acute leukemias. (A) α-bisabolol activity against blasts ex vivo, here grouped by diagnosis. The corresponding IC50 values and number of cases (n) are shown. The differences between the Ph-B-ALL sensitivity curves and the other ones were statistically significant (p < 0.05). Each point is the mean ± SD of 14 cases. (B) α-bisabolol sensitivity clustering analysis. The samples were grouped by complete linkage hierarchical clustering algorithm available in MultiExperiment Viewer http://www.tm4.org/mev/. The heat map was obtained by subtracting spontaneous mortality to scaled α-bisabolol 24-hour cytotoxicity expressed as percentage. Three main groups of patients were identified based on their cytotoxicity response. The Ph-B-ALL (ALL) cases shared the highest sensitivity and were grouped mainly in the first sensitivity cluster, whereas AML cases were split into two groups with intermediate and lower sensitivities. Ph+B-ALL (Ph+) cells were scattered among the three groups, although they were mainly clustered in the second group. At the bottom, the 24-hour dose-response curves of the three sensitivity clusters are depicted, and the corresponding IC50 values and number of cases (n) are shown. The differences between the curves were statistically significant (p < 0.05).