Probe Selectivity in Vitro:
Kinase selectivity was first determined in biochemical assays for a panel of 68 protein kinases and 9 lipid kinases. Only PIM2 was significantly inhibited with an IC50 of <0.003 μM, the lowest sensitivity range for the assay. Also GSK3β, PKN1, and PKCτ, were inhibited but at a significantly lower potency with IC50 between 1 and 5 μM. Additional kinase profiling against 442 kinases using the KINOMEscan at 1 uM, indicated high kinase selectivity [S(35) = 0.021 at 1 μM, 386 nonmutant kinases including PIMs 1, 2, and 3; S(35) = 0.013 at 1 μM, 383 nonmutant kinases not including PIMs 1, 2, and 3].