Effect of GW654652 on HUVEC and MM cell growth. (A) Dose-related effects of GW654652 on survival (left) and proliferation (right) of HUVECs. HUVECs were cultured with control media or with GW654652 followed by no removal (▪) or removal (□) of GW654652. (B-C) Shown are dose-related effects of GW654652 on survival and proliferation of MM.1S (B) and MM.1R cells (C) and of RPMI-Dox40 (Dox40), U266, and RPMI cells (D). In each case, cell lines were cultured with control media or with the indicated concentrations of GW654652 (closed symbols). In MM.1S and MM.1R, cell assays were also performed after the removal of GW654652 (B-C; □). MTT cleavage (left) or [³H]-thymidine uptake (right) was measured during the last 8 and 4 hours, respectively, of 48-hour cultures. Values represent the mean ± SD absorbance or [³H]-thymidine uptake of triplicate cultures.