Abstract

This study aims to uncover the regulatory mechanism behind the up-regulation of dual-specificity phosphatase 28 in hepatocellular carcinoma. The differential expression and survival analyses of studied genes were carried out by the Encyclopedia of Ribonucleic Acid Interactomes platform. The GeneMANIA and biological general repository for interaction datasets were applied to obtain the regulatory network of dual-specificity phosphatase 28. Western blot analyzed the protein expression levels of dual-specificity phosphatase 28 and Josephin domain containing 2 in clinical samples collected from hepatocellular carcinoma individuals. To study the functions of dual-specificity phosphatase 28 and Josephin domain containing 2, transfection was performed in hepatocellular carcinoma cells, of which efficiency was determined by quantitative real-time polymerase chain reaction and Western blot. Cell proliferation was evaluated by colony formation and ethynyl deoxyuridine assays. Both dual-specificity phosphatase 28 and Josephin domain containing 2 were found to be highly expressed in hepatocellular carcinoma. The overexpression of dual-specificity phosphatase 28 exerts a promotion role in the cell proliferation and migration of human hepatocellular carcinoma cells, whereas the deletion of dual-specificity phosphatase 28 exhibited the opposite role. Bioinformatics tools found that Josephin domain containing 2 is an interacted gene of dual-specificity phosphatase 28, which was verified by co-immunoprecipitation. Josephin domain containing 2 regulates dual-specificity phosphatase 28 stability through deubiquitination. Furthermore, overexpressing dual-specificity phosphatase 28 reversed both the proliferation and migration of hepatocellular carcinoma cells inhibited by Josephin domain containing 2 silencing. Josephin domain containing 2 interacts with and deubiquitinates dual-specificity phosphatase 28 to improve its protein stability, thereby promoting the proliferation and migration of hepatocellular carcinoma cells.