JNK inhibitor SP600125 promotes pSMAD3C/SMAD4 complex-induced reduction of c-Myc expression. (A) Lysates from Hep3B-HBx and Huh7-HBx cells treated with 10 ng/ml TGF-β1 together with DMSO or 10 µM SP600125 for 0.5 h were subjected to western blot with p-JNK1/2, pSMAD3C (Ser423/425) and pSMAD3L (Ser213). (B) Lysates from Hep3B and Huh7 cells treated with 10 ng/ml TGF-β1 together with DMSO or 10 µM SP600125 for 72 h were subjected to western blot analysis with c-Myc, p21/Cip1 and p15/INK4b. JNK, c-Jun N-terminal kinase; vec, vector; p, phosphorylated; t, total; HBX, hepatitis B virus X protein; DMSO, dimethyl sulfoxide.