Towards this goal, we demonstrate that in an ICC cell line, TGF-β induces ERK phosphorylation via Smad pathway and blocking this activation with U0126, a MEK1/2 inhibitor, results in the inhibition of TGF-β tumor promoting activity and the enhancement of its anti-proliferative role. This evidence concerns the gene MAP2K1 and intrahepatic cholangiocarcinoma.