CO-029 mediates TNFα/TNFαR1 induced epithelial mesenchymal transition in intrahepatic cholangiocarcinoma

Objective To investigate the role of transmembrane protein CO-029 in epithelial mesenchymal transition (EMT) induced by tumor necrosis factor alpha (TNFα) of intrahepatic cholangiocarcinoma (ICC) cells. Methods RT-PCR and Western blot were conducted to detect the CO-029 expression in ICC cells and tissues. The effect of CO-029 silencing by lenti-virus on EMT induced by TNFα was investigated. Western blot and mass spectrometry after immunoprecipitation were used to confirm whether TNFαR1 can directly or indirectly bind with CO-029 to form complexes in ICC. Results Differential expression of CO-029 was observed in ICC cells and tissues. The expression of CO-029 was significantly reduced by lenti-viral interference in ICC cells, resulting in the failure of TNFα to induce EMT. TNFαR1 in ICC could directly or indirectly form complexes with CO-029. Conclusion CO-029 mediates TNFα/TNFαR1 induced EMT in ICC, which might play an important role in the invasion and metastasis. Key words: Intrahepatic cholangiocarcinoma; Transmembrane protein, CO-029; Tumor necrosis factor; Epithelial mesenchymal transition; Invasion; Metastasis