Fig. 4.

Effects of TGF-β signaling on expression of p27. (A) HIT-T15 cells were treated with or without 5 ng/ml TGF-β1, and/or with DMSO or 2 µM SB-431542, for 2 days. Western blotting of the whole cell extracts for p27, and GAPDH, which was used as a control. (B) Results are displayed as the relative protein level of p27. Six repeats of the Western blotting were done independently. The data are mean±SD (error bars) of a representative experiment. *p<0.001. (C, D) Luciferase reporter assays in HIT-T15 cells. Cells were transfected with either p27 luciferase reporter p27PF or empty luciferase reporter pGVB2. In addition, transfection was performed, to stimulate TGF-β signaling, together with or without ALK5* in (C), or to inhibit TGF-β signaling, together with treatment with either DMSO or 2 µM SB-431542 in (D). All data shown are mean±SD (error bars) of a representative experiment performed in at least triplicate. n.s.: not significant.