Abstract:

Objective To investigate the expression and effect of CDKN3 in intrahepatic cholangiocarcinoma and its molecular mechanism. Methods The expression of CDKN33 was analyzed by bioinformatics and immuno⁃ histochemistry. CDKN3 interference plasmid，CDKN3 overexpression plasmid and negative control plasmid were transferred into intrahepatic cholangiocarcinoma cell line（HCCC⁃9810）and the transfection effect was detected by western blot. Proliferation and migration ability of HCCC⁃9810 cells were detected by colony formation experiment and healing experiment. The expression of related pathway proteins was detected by western blot. Cell cycle asssay was used to analyze the proportion of cells at various stages. Results CDKN3 was highly expressed in cholangio⁃ carcinoma when compared with that in normal tissues（P < 0.05）. KEGG and GO enrichment analysis showed that CDKN3 was closely related to G2/M checkpoint of cell cycle. Interfering CDKN3 induced G2/M phase arrest of HCCC⁃9810 cells，resulting in decreased proliferation and migration（P < 0.05）. Further studies showed that CDKN3 silence down⁃regulated the activity of CDC25C/CDK1 axis，leading to increased phosphorylation level（P < 0.05）. In addition，CDKN3 overexpression significantly reduced the sensitivity of HCCC⁃9810 cells to cisplatin（P < 0.05）. Conclusion CDKN3 is significantly up⁃regulated in intrahepatic cholangiocarcinoma. CDKN3 may be involved in the development of intrahepatic cholangiocarcinoma by regulating the expression of proteins related to G2/M checkpoint.

Key words:

intrahepatic cholangiocarcinoma, CDKN3, cell cycle, chemoresistance