Fig 1: Lead compound F7/PIK75 targets activity of multiple kinases, including pI3K and p38γ.Cell viability was measured and normalized to DMSO controls in Hut78 cells treated with varying concentrations of three potent PI3K-specific inhibitors (BEZ235, GDC-0941, or A66) and F7/PIK75. Inset table shows calculated IC50 values. (a) Comparison of IC50 for inhibition of PI3K kinase activity by three PI3K-specific inhibitors (BEZ235, GDC-0941, or A66) and F7/PIK75. This table is summarized from publicly available databases (summarized from the companies of Selleck [Houston, TX] and Apexbio [Boston, MA]). (b) Cell-freeebased p38γ kinase assay using ADP Glo was performed with indicated concentrations (1 μmol/L and 10 μmol/L) of three PI3K-specific inhibitors (A66, GDC-0941, or BEZ235) and 1 μmol/L of F7/PIK75. Staurosporine (1 μmol/L), a pan-kinase inhibitor, was used as a positive control. (c) Hut78 cells were transduced with shRNA against PI3K 110α or control shRNA. (Top) Western blot was used to visualize protein expression of PI3K 110α. Actin is a control for protein loading. (Bottom) Trypan blue exclusion was used to measure cell viability as a percentage of control-treated cells. Three replicates were performed. *P < 0.05. (a) Western blot was used to visualize A66 effects on Hut78 cells, indicated by protein expression level of downstream targets of PI3Kp110α. GAPDH is a control for protein loading. Contr, control; Ctr, control; IC50 half maximal inhibitory concentration; M, mol/L; PI3K, phosphatidylinositol 3 kinase; sh, short hairpin; uM, μmol/L.