Centromeric protein K (CENPK) promotes gastric cancer proliferation and migration via interacting with XRCC5.

Background: CENPK is a novel oncogene which is aberrantly expression in some malignant tumors. However, the role and mechanisms of CENPK in gastric cancer have not been explored. Methods: In this study, we use RT-PCR and IHC to study CENPK expression in gastric cancer cells and tissues. In addition, we constructed the two kinds of CENPK siRNA lentivirus to knock down CENPK. Then, we use High content living cell imaging System, Cell Counting Kit-8, colony formation, wound healing and Transwell assays to demonstrate the function of CENPK on gastric cancer cells AGS and MKN45. Meanwhile, we use flow cytometry assay to study CENPK function on gastric cancer cell apoptosis and cell cycle arrest. Subcutaneous tumorigenesis in nude mice was also performed to confirm CENPK function on gastric cancer. Finally, we use Co-IP, LC-MS and function rescue assay to study the downstream interaction molecular of CENPK. Results: We demonstrated that CENPK expression were up-regulated in GC cell lines. Poor differentiation and III-IV stage had more percentages of high CENPK expression. Knocking down CENPK could significantly suppress GC cells proliferation, migration and invasion, and induce GC cells apoptosis and G1/S phase transition arrest. Subcutaneous tumorigenesis confirmed the tumor-promoting effects of CENPK in vivo. Remarkably, we found for the first time that XRCC5 might be interacted with CENPK through Co-IP, LC-MS and rescue study. Conclusion: CENPK promotes GC cell proliferation and migration via interacting with XRCC5 and may be a novel prognostic factor or therapeutic target for CENPK. [ABSTRACT FROM AUTHOR]