Activation of Akt and downstream targets are dependent upon PI3K activity. PI3K/Akt pathway inhibition studies were performed with all 4 MCL cell lines using 3 different inhibitors: LY294002, wortmannin, and Akt inhibitor (Calbiochem). Comparable results were obtained for each line, and results with Granta 519 using LY294002 or Akt inhibitor are shown in representative experiments. Akt inactivation occurs after 8 hours (8 h), followed by the abrogation of phosphorylation of Bad, FRKHL-1, MDM2, and p27^kip1 after 24 hours (24 h). Translational control proteins mTOR, p70S6K, and S6K show a time-dependent decrease in phospho-protein levels. S6K and total Akt levels are shown as loading control.