Effect And Mechanism Of BTN3A3 On Inhibiting Malignant Biological Behavior Of Gastric Cancer Cells

ObjectiveGastric cancer,a common malignant tumor of digestive system,is a disease with high morbidity and mortality,and lacks effective screening means and effective treatment technology in early stage.Therefore,in-depth research on the pathogenesis of gastric cancer will be helpful for the prevention and control of gastric cancer,clinical diagnosis and treatment,and improve the health quality of the population.Butyrophilin Subfamily3 MemberA 3(BTN3A3),one of the main members of the lactophilin subfamily,is expressed in a variety of diseases and plays a regulatory role.It is unclear whether there is a regulatory role in the progression of gastric cancer.The purpose of this study is to study the regulatory effect of BTN3A3 on the malignant biological behavior of gastric cancer cells,preliminarily clarify its molecular mechanism,and provide a new target for the diagnosis and treatment of gastric cancer.MethodsThe expression characteristics and clinicopathological significance of BTN3A3 in gastric adenocarcinoma were studied by immunohistochemical staining.In human gastric cancer cell lines AGS and HGC-27,the protein expression level of BTN3A3 was differentially expressed by transfection plasmid or siRNA,and the regulatory effects of BTN3A3 on the migration and invasion ability of gastric cancer cells were detected by scratch assay and Transwell assay.The effect of BTN3A3 on the proliferation of gastric cancer cells was detected by MTT assay.By Western blot assay,relevant downstream target molecules of BTN3A3 were screened to preliminarily clarify the molecular mechanism of BTN3A3’s regulatory effect on malignant biological behavior of gastric cancer cells.ResultOur research group collected 104 cases of gastric adenocarcinoma and adjacent tissues.Immunohistochemical staining techniques were used to study BTN3A3,which was mainly located in the cytoplasm and cell membrane in gastric adenocarcinoma tissues.Btn3a3 was low expressed in gastric adenocarcinoma tissues,and its expression was different in different pathological grades,T stages and lymph node metastasis levels.In human gastric cancer cell lines AGS and HGC-27 cells,the expression level of BTN3A3 was up-regulated or down-regulated by transfection plasmid or siRNA,respectively,and it was found by scratch and Transwell experiments that:The migration and invasion ability of the two kinds of cells was enhanced after the down-regulation of BTN3A3 protein expression level,while the migration and invasion ability of the two kinds of cells was weakened after the up-regulation of BTN3A3 protein expression level,suggesting that BTN3A3 can inhibit the migration and invasion ability of gastric cancer cells.Western blot test found that:After downregulating the expression level of BTN3A3 protein,the expression levels of epithelium-mesenchymal transformation-related proteins N-cadherin,Snail,Slug,MMP7 and MMP9 in gastric cancer cells increased,while the expression levels of E-cadherin decreased.However,after up-regulating the expression level of BTN3A3 protein,The expression levels of N-cadherin,Snail,Slug,MMP7 and MMP9 decreased,while the expression levels of E-cadherin increased,suggesting that BTN3A3 might inhibit the motor ability of gastric cancer cells by inhibiting EMT.MTT assay showed that the proliferation capacity of AGS and HGC-27 cells was enhanced after down-regulating the expression level of BTN3A3 protein,while the proliferation capacity of the two cells was weakened after up-regulating the expression level of BTN3A3.Western blot assay showed that the expression level of Cyclin D1 was increased after the downregulation of BTN3A3,while the expression level of Cyclin D1 was decreased after the up-regulation of BTN3A3.It is suggested that BTN3A3 may inhibit the proliferation of gastric cancer cells by inhibiting cell cycle.Conclusion1.BTN3A3 is mainly located in the cytoplasm and cell membrane in gastric adenocarcinoma tissues,and its expression is low in gastric adenocarcinoma tissues,and the expression is different in different pathological grades,T stages and lymph node metastasis levels.2.BTN3A3 can inhibit the migration and invasion ability of gastric cancer cells by inhibiting EMT.3.BTN3A3 can inhibit the proliferation of gastric cancer cells by inhibiting the expression of cyclin D1.