Figure 5.

LY294002 restores chemosensitivity to 5-FU in Smad4-deficient cells. (A) CT26 and (B) SW620 clones were treated with indicated concentrations of 5-FU with or without LY294002 for 72 h. Relative percentages of live cells were analysed by MTT assay. IC₅₀ values were calculated using linear or logarithmic regression (R²>0.9). Data are presented as the mean±s.d. from triplicate wells. (C and D) Cell apoptosis was examined by FACS analysis 48 h after 5-FU and/or LY294002 treatment. The percentages of apoptotic cells are shown as the mean±s.d. from three wells. (E) CT26 and SW620 clones were treated with 5-FU and/or LY294002 for 24 h and cell lysates were used for western blot analyses. All of the experiments were performed for one parental, one vector, and three stable clones from each cell line, and triplicated.