Taken together, the data obtained from our study suggest that: (1) IL-9 promotes proliferation of cultured ICC; (2) IL-9 reinforces the CCK-8 or CCh-induced Ca2+ transients in ICC; (3) IL-9 may facilitate maintenance of ICC function under culture condition; (4) IL-9 probably exerts its functions via IL-9R expressed by ICC. This evidence concerns the gene IL9 and intrahepatic cholangiocarcinoma.