Expression Of Special AT Rich Sequence Binding Protein 1 In Gastric Cancer Tissue And Its Effect On The Biological Behavior Of Gastric Cancer Cells

Objective: Special AT rich sequence binding protein 1(SATB1)can be highly expressed in tumor cells and promote tumor cell proliferation and metastasis,which is a potential therapeutic target for tumors.This study was to investigate the expression of SATB1 in gastric cancer and its effect on the biological behavior of gastric cancer cells,in order to provide reference for the treatment of gastric cancer.Methods: 1.Immunohistochemistry was used to detect the expression of SATB1 in 30 cases of gastric cancer,lymph node tissue and adjacent tissues.2.RT-PCR and Western blot were used to detect the m RNA and protein content of SATB1 in gastric cancer cell line MGC-803?HGC-27 and normal gastric mucosal immortalized cell GES-1.3.The eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-SATB1 sh RNA(sh-SATB1),silencing vector plasmid p PLK+Puro(sh-N)were transfected into MGC-803 cells by Lip2000.4.Western blot analysis the expression of SATB1 and biological behavior-related proteins in MGC-803 cells after transfected with eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-sh RNA(sh-SATB1)and silencing vector plasmid p PLK+Puro(sh-N).5.CCK8 assay analysis the cell proliferation after eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-sh RNA(sh-SATB1)and silencing vector plasmid p PLK+Puro(sh-N)were transfected in MGC-803 cells.6.Cell clone formation assay to detect cell clone formation ability after eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-sh RNA(sh-SATB1)and silencing vector plasmid p PLK+Puro(sh-N)were transfected in MGC-803 cells.7.Flow cytometry for cell cycle and apoptosis after eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-sh RNA(sh-SATB1)and silencing vector plasmid p PLK+Puro(sh-N)were transfected in MGC-803 cells.8.Wound Healing and Transwell test to detect cell migration ability after eukaryotic expression plasmid pc DNA3.1(+)-His-SATB1(His-SATB1),vector plasmid pc DNA3.1(His-N),silencing plasmid p PLK+Puro-sh RNA(sh-SATB1)and silencing vector plasmid p PLK+Puro(sh-N)were transfected in MGC-803 cells.9.Statistical analyses were performed using SPSS 17.0 statistical software.All data were presented as the mean ± standard deviation.The Student t test was used to determine significance of changes between two groups.Mann–Whitney test following Friedman ANOVA was used for multiple comparisons where appropriate.The frequencies of SATB1 expression among cancer samples were analyzed by the c2 test with modification by the Fisher's exact test to account for frequency values < 5.Normality was verified for all data.Values of p < 0.05 were considered to be statistically significant.Results: 1.High expression of SATB1 in gastric cancer tissues and gastric cancer cells Compared with adjacent tissues,SATB1 is highly expressed in gastric cancer tissues and metastatic lymph node tissues(p<0.05).Compared with normal gastricmucosal epithelial cells GES-1,SATB1 m RNA and Protein levels were highly expressed in gastric cancer cells MGC-803 and HGC-27(p<0.05).2.Compared with the sh-N group,the expression of SATB1 protein was significantly decreased in the sh-SATB1 group of MGC-803 cells.Compared with the His-N group,the expression level of SATB1 protein in the His-SATB1 group was significantly increased(p<0.05).3.Compared with the sh-N group,the proliferation activity and colony forming ability of the MGC-803 cells in the sh-SATB1 group were significantly decreased,and the expression levels of the cell proliferation-related proteins AKT and p AKT were decreased.Compared with the His-N group,the His-SATB1 group was compared.MGC-803 cells have significantly increased proliferation and clonality,and the expression levels of cell proliferation-related proteins AKT and p AKT are elevated(p<0.05).4.Compared with the sh-N group,the MGC-803 cells in the sh-SATB1 group cell cycle was arrest in the G0/G1 phase,the expression levels of the cycle-related proteins cyclin D1 and CDK4 were decreased,while the expression level of the cyclin-dependent kinase inhibitor p21 was increased;Compared with the His-N group,the MGC-803 cells in the His-SATB1 group were transformed into the proliferative G2 phase,the expression levels of the cycle-related proteins cyclin D1 and CDK4 were increased,while the expression level of the cyclin-dependent kinase inhibitor p21 was reduced(p<0.05).5.Compared with sh-N group,the apoptosis of MGC-803 cells in sh-SATB1 group increased,the expression level of anti-apoptotic molecule bcl-2 decreased.Compared with His-N group The apoptosis of MGC-803 cells in His-SATB1 group decreased,the expression level of anti-apoptotic molecule bcl-2 increased(p<0.05),regardless of sh-SATB1 group or His-SATB1 group.The proapoptotic molecule bax did not change significantly.6.Compared with sh-N group,the migration ability of MGC-803 cells in sh-SATB1 group was significantly decreased,and the expression levels of migration-related proteins ?-catenin,MMP2 and MMP9 were decreased.Compared with the His-Ngroup,the migration ability of MGC-803 cells in His-SATB1 group was significantly increased,and the expression levels of migration-related proteins ?-catenin,MMP2 and MMP9 were increased(p<0.05).Conclusion: 1.SATB1 is highly expressed in gastric cancer tissues and cells.2.SATB1 can promote the proliferation,cycle progression and apoptosis of gastric cancer cells.This phenomenon may be caused by the activation of PI3K/AKT signaling pathway and the regulation of AKT,p21,bcl-2 proteins.3.SATB1 promotes the migration of gastric cancer cells,which may be caused by activation of the Wnt/?-catenin signaling pathway.