Downregulation of ROS-FIG inhibits cell proliferation, colony‑formation, cell cycle progression, migration and invasion, while inducing apoptosis in intrahepatic cholangiocarcinoma cells.

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer with poor responsiveness to existing drug therapies. Therefore, novel treatment strategies against ICC are required to improve survival. The aim of this study was to demonstrate the role of fused-in-glioblastoma-c-ros-oncogene1 (FIG-ROS) fusion gene in ICC. ROS was positively expressed in ICC tissues and HUCCT1 cells. Plasmids expressing ROS- and FIG-specific shRNAs were constructed and transfected into HUCCT1 cells. The results showed that single transfection of ROS- or FIG-specific shRNA inhibited HUCCT1 cell proliferation, colony formation, cell cycle progression, migration and invasion, while inducing apoptosis. Moreover, the co-inhibition of ROS- and FIG-specific shRNA exhibited stronger effects on HUCCT1 cell proliferation, apoptosis, colony formation, cell cycle progression, migration and invasion, when compared to single inhibition of ROS and FIG. Furthermore, findings of this study suggested that the AKT signaling pathway was involved in the ROS-FIG-mediated biological processes of HUCCT1 cells. In summary, the results suggest that FIG-ROS plays an oncogenic role in ICC. Additionally, ROS1-6290 and FIG-363 segments may become effective therapeutic targets for ICC harboring ROS-FIG fusion protein.