Proteomics research about effect of zinc finger protein 139 knockdown with RNA interference on serum of orthotopic transplantation nude mouse with gastric cancer

Abstract

Objective To observe the effect of inhibiting zinc finger protein 139 (ZNF139) on serum proteins in orthotopic transplantation nude mice model with gastric cancer,and to investigate the mechanism for ZNF139 involved in progression of gastric cancer.Methods Small interfering RNA (siRNA) recombinant plasmid targeting ZNF139 gene was constructed and imported into gastric cancer cell line SGC7901.After screened stably transfected cells by G418,gastric cancer cells were injected into nude mice subcutaneously.Transplanted tumor tissue was constructed through repeatedly subcutaneously inoculating and passaging between nude mice,and 6th-generation subcutaneous tumor was pasted with OB biological glue orthotopically on the stomach wall of BALB/c nude mice.The proteins in nude mice serum samples were separated by fluorescence two-dimensional difference gel electrophoresis (2D-DIGE) and the differential proteins were identified by liquid chromatography-mass spectrometry (LC-MS).Parts of the proteins were identified by Western blotting.Results The tumor-forming rate in orthopotic implantation was 100％ (15/15).ZNF139 was inhibited obviously,and the tumor growth of orthotopic transplantation nude mice model was obviously slower in siRNA-ZNF139 group.Five differential proteins were identified in orthotopic transplantation nude mice serum samples.Results showed that apolipoprotein E (APOE) and the kininogen 1 (KNG1) were down-regulated in gastric cancer orthotopic mouse serum,and mTERF was upregulated after siRNA-ZNF139 interference.Results of Western blotting were consistent with proteomics.Conclusion ZNF139 in gastric cancer may up-regulate serum levels of APOE and KNG1,while down-regulate mTERF to participate in the progression of gastric cancer. Key words: Orthotopic transplantation of gastric cancer; Zinc finger protein 139; Proteomics