Chemokine (C-C motif) ligand 18/membrane-associated 3/forkhead box O1 axis promotes the proliferation, migration, and invasion of intrahepatic cholangiocarcinoma

Phosphatidylinositol Transfer Protein, Membrane-Associated 3 (PITPNM3) often bind with chemokine (C-C motif) ligand 18 (CCL18) to promote tumor progression. However, the role of PITPNM3 in intrahepatic cholangiocarcinoma (ICC) is unclear. We first searched GEPIA database and detected the PITPNM3 expression using immunohistochemistry and real-time quantitative PCR. The results showed that PITPNM3 is high expression in ICC tissues and cells. Then we investigated the cell function of CLL18 and PITPNM3 through cell clone formation assay and transwell assay. The results indicated that CCL18 treatment promoted the proliferation, migration, and invasion of ICC cells. Silence of PITPNM3 reversed the effect of CCL18 on cell function. Simultaneously, we detected key protein expression of forkhead box O1 (FOXO1) and nuclear factor kappa B (NF-KB) through western blotting and found that CCL18 activated NF-KB pathway while inhibited FOXO1 pathway, the effect of which were attenuated by silence of PITPNM3. Finally, we confirmed which pathway affected the cell function using inhibitor of FOXO1 (AS1842856) and activator of NF-KB (Asatone). The results showed that AS1842856, not Asatone, relieved the inhibitory effect of si-PITPNM3 on the cell function of CCL18. In short, CCL18 treatment activated PITPNM3 to promote the proliferation, migration, and invasion of ICC via FOXO1 signaling pathway. These results provided a new insight for the diagnosis and therapy of ICC.