The Role And Clinical Significance Of CircSMARCA5 In Gastric Cancer

Objective:Gastric cancer is the fifth most common malignant tumor.Although the diagnosis and treatment of gastric cancer has made progress in recent years,the prognosis of patients with advanced gastric cancer is poor.The specific expression of circRNA is closely related to the development of cancer.Some studies have found that circSMARCA5 has low expression in hepatocellular carcinoma,which inhibits the proliferation and migration of hepatocellular carcinoma cells.In this study,the expression of circSMARCA5 in gastric cancer cells and tissues was detected to determine the correlation between circSMARCA5 and clinical pathological data.Objective to study the effect of knockdown and overexpression of circSMARCA5 on the biological function of gastric cancer cells in vitro and in vivo,to explore the mechanism of circSMARCA5 in gastric cancer,it is expected to provide a new potential marker for the diagnosis and treatment of early gastric cancer.Methods:1.This experiment by using the fluorescent quantitative PCR(qRT-PCR)to detect circSMARCA5 in gastric cancer cell line and the expression level of patients with gastric cancer pathological tissues,collected the related clinical pathologic data(gender,age,size of tumors and lymph node metastasis,distant metastasis,blood vessels,nerve invasion,TNM staging,etc.),analyzing circSMARCA5 correlation with clinical data,to explore it as a potential diagnostic markers of gastric cancer.2.Human gastric cancer cells MGC-803 and MKN-45 were transfected with si-smarca5 and si-control,and AGS and BGC-823 were transfected with circSMARCA5 overexpressing plasmid.The effects of circSMARCA5 on the proliferation and apoptosis of human gastric cancer cells were investigated by cell growth curve measurement,cloning experiment and flow cytometry,and the interference of circSMARCA5 was detected by qRT-PCR and Western blot.Changes of genes and proteins related to proliferation and apoptosis of human gastric cancer cells.3.Transwell cell invasion and migration experiments showed that overexpression of circSmarCA5 could inhibit the invasion and migration of gastric cancer cells.QRT-PCR and Western blot were used to detect the levels of proteins related to EMT signaling pathway,so as to predict the signaling pathway that regulates the EMT process of gastric cancer cells.Results:1.Real-time quantitative PCR showed that the expression level of circSMARCA5 in gastric cancer tissues and gastric cancer cells was lower than that in normal gastric tissues and human gastric mucosa epithelial cells.Correlation analysis of clinical data and PCR expression results showed that the expression level of circSMARCA5 was correlated with the degree of tumor differentiation,lymph node metastasis,vascular and nerve invasion,and TNM staging.2.Fluorescence quantitative PCR showed that the expression level of circsmarCA5 in the knockdown group was significantly decreased,while that in the overexpression group was significantly increased.Silencing of circSMARCA5 can promote the proliferation and inhibit apoptosis of gastric cancer cells,while overexpression of circSMARCA5 can inhibit the proliferation and promote apoptosis of gastric cancer cells.3.Transwell cell invasion and migration experiments showed that overexpression of circSmarCA5 could inhibit the invasion and migration of gastric cancer cells.QRT-PCR and Western blot were used to detect the levels of proteins related to EMT signaling pathway,so as to predict the signaling pathway that regulates the EMT process of gastric cancer cells.Conclusions:Low expression of circSmarCA5 in gastric cancer cells and tissues is closely related to lymph node metastasis.circSMARCA5 can inhibit the proliferation and promote apoptosis of gastric cancer cells.TGF-β/Smad signaling pathway regulates the EMT process of gastric cancer cells and inhibits the invasion and migration of gastric cancer cells.It is expected to be a new potential marker for diagnosis and prognosis of gastric cancer.