Screening Of Pancreatic Cancer Prognostic Genes Based On Bioinformatics And The Expression And Clinical Significance Of RAD18 In Pancreatic Cancer

Objective: Searching for the genes associated with pancreatic cancer prognosis by using bioinformatics methods;Then,the expression and clinical significance of RAD18 in pancreatic cancer were analyzed by using immunohistochemistry.Methods: The pancreatic cancer-related microarray dataset was derived from the GEO database,and the R language limma package was used for differential analysis to obtain common differential genes;The cluster Profiler package was used for GO and KEGG enrichment analysis of differential genes;To obtain key genes,the STRING online database and Cytoscape software were used to build protein-protein interaction networks;GEPIA online database was used to verify the difference in expression of key genes in pancreatic cancer tissues and analyze the impact of key genes on the prognosis of pancreatic cancer patients.Finally,immunohistochemical staining was used to verify the expression of RAD18 in pancreatic cancer tissues and its effect on the prognosis of pancreatic cancer patients at the histological level.Results: In the two datasets GSE15471 and GSE62452,a total of 212 common differential genes were obtained.The differential genes were mainly enriched in extracellular matrix-receptor interaction,protein digestion and absorption,focal adhesion,and PI3K-Akt signaling pathway.Ten key genes were screened by PPI network.Prognostic analysis showed that RAD18 expression is associated with shorter overall and disease-free survival in patients.Immunohistochemical staining results showed that RAD18 was positively expressed in pancreatic cancer tissues,and the positive rate was significantly higher than that in adjacent non-cancer tissues(P < 0.05),and the expression level of RAD18 was related to TNM stage and lymph node metastasis.Kaplan-Meier survival analysis showed that higher RAD18 expression was associated with lower overall survival.Multivariate COX regression analysis showed that RAD18 expression,tumor size and TNM stage were predictors of overall survival in patients with pancreatic cancer.Conclusion: RAD18 was positively expressed in pancreatic cancer,and its expression was negatively correlated with the prognosis of patients with pancreatic cancer.It is expected to become a potential biomarker for the diagnosis and prognosis of pancreatic cancer in the future.