Effects Of CCNB2 On Invasion And Metastasis Of Triple-negative Breast Cancer

Object:To explore potential therapeutic targets through bioinformatics analysis and verify its impact on the invasion and metastasis of triple-negative breast cancer（TNBC）.Methods:Three gene expression profiles from the GEO database（GSE64790,GSE62931 and GSE38959）were analyzed.Differentially expressed genes（DEGs）between TNBC and normal tissues were screened by GEO2 R online analysis tool,and Gene Ontology（GO）functional annotation and Kyoto Encyclopedia of Genes（KEGG）pathway enrichment analysis were performed on them.The protein-protein interaction network（PPI）of DEGs was visualized using the Metascape online biological website,and related core genes were identified.Subsequently,transcriptional data of core genes in patients with breast cancer were investigated in the ONCOMINE database.Kaplan-Meier survival analysis was used to evaluate the prognostic value of core gene expression levels in patients with TNBC.The TNBC cell line MDA-MB-231 was cultured,and si RNA CCNB2 group,negative control group and blank control group were set up by transfection of si RNA.Western blot was used to detect the expression of CCNB2 protein in each group,CCK-8 test was used to detect the change of cell proliferation ability in each group,cell scratch test was used to observe the migration of cancer cells,and transwell test was used to detect the invasion ability of cells in each group.Finally,the clinical pathology and long-term follow-up data of 39 patients with TNBC in the First Affiliated Hospital of Bengbu Medical College from January 2014 to July 2020 were retrospectively analyzed.Immunohistochemical method was used to detect the expression and subcellular localization of CCNB2 in TNBC.Results:A total of 66 DEGs were identified between TNBC and normal tissues,including 33up-regulated genes and 33 down-regulated genes.In addition,five core genes were identified by the potential protein complex.High expression of these core genes,especially CCNB2 overexpression,was associated with poor prognosis in patients with TNBC.The expression level of CCNB2 protein in MDA-MB-231 cells transfected with CCNB2 si RNA was significantly decreased（P<0.05）,and its proliferation,migration and invasion abilities were also significantly decreased（P<0.05）.CCNB2 protein was expressed in the cytoplasm,and the expression in TNBC tissues was significantly higher than that in adjacent non-tumor tissues.The expression of CCNB2 was significantly correlated with the overall survival of patients（P<0.05）.Conclusion:CCNB2 may play an important role in the occurrence and development of TNBC and has the potential to serve as a prognostic marker for TNBC.