Cotreatment with LBH and rapamycin exerts synergistic cytotoxic effects against DLBCL cells. (A-B) DHL-6 (A) and Ly7 (B) cells were treated with the indicated concentrations of LBH589 and/or rapamycin for 48 hours and survival was assessed as described before. (C-D) Effect of LBH + Rap on DLBCL cell proliferation. DHL-6 and Ly7 cells were treated with the indicated doses of LBH and/or rapamycin for 48 hours and cell proliferation was assessed by ³H-thymidine incorporation. One representative experiment is shown for each line (n = 3). Error bars indicate mean ± SD from 3 determinations.