Construction Of Cerna Regulatory Network To Search For Biomarkers And Analysis Of Immune Infiltration

Gastric cancer is the most common gastrointestinal malignant tumor,which has caused a significant economic and social burden worldwide.The prevention,pathogenesis,treatment and prognosis of gastric cancer deserve further investigation.Non-coding RAN plays an important role in the occurrence and development of gastric cancer,especially the interaction between long non-coding RNA(lncRNA)and micro RNA(miRNA).Objective: To study the interaction and competitive binding between lncRNA and miRNA related to gastric cancer to regulate the relationship network of downstream mRNA,construct a prognosis model of gastric cancer related to lncRNA and explore the immune microenvironment of gastric cancer.Methods: The expression data related to gastric cancer were downloaded from the TCGA database and the differential expression was analyzed.The differentially expressed lncRNA was compared with the miRNA to obtain corresponding relationship pairs and construct the competitive endogenous RNA network(ceRNA).To further analyze the survival-related lncRNA and construct a lncRNA related prognosis model of gastric cancer.The differences of immune cell infiltration and immune checkpoints between the low-risk group and the high-risk group were analyzed.Finally,the corresponding lncRNA was verified at the cell and tissue levels by real-time quantitative PCR.Results: First,we constructed a ceRNA network with 32 mRNA,90 lncRNA and 33 miRNA.Then,based on the results of univariate cox survival analysis of lncRNA in ceRNA network,a prognostic model with 14 lncRNA was constructed.The risk score of this model was an independent prognostic indicator of survival,and it was superior to the traditional clinical pathological features in predicting the prognosis of gastric cancer.In addition,the low-risk group and the high-risk group showed significant differences in aspects such as immune cell infiltration and immune checkpoints.Finally,we verified the expression of lncRNA ADAMTS9-AS1 at the cellular and tissue levels,and found that it was lowly expressed in gastric cancer cell lines and gastric cancer tissues.Conclusion: The research obtained the ceRNA regulatory network of gastric cancer,which provided reference for the mechanism of gastric cancer.The prognosis model of gastric cancer can predict the prognosis of gastric cancer and provide therapeutic targets.