Identification of a five-gene prognostic signature related to B cells infiltration in pancreatic adenocarcinoma
Abstract Background: Pancreatic adenocarcinoma (PAAD) is an extremely malignant cancer. Immunotherapy is a promising avenue for elevating survival time of PAAD patients.Methods: The RNA sequencing and clinical data of PAAD were downloaded from the TCGA database. The ssGSEA method and weighted gene co-expression network analysis were used to calculate the relative abundance of tumor-infiltrated immune cells and identified the immune cells closely related module. Least absolute shrinkage and selection operator (LASSO) and Cox regression analysis were used to construct a prognostic model. MCPcounter and EPIC were also applied to assess the immune cell components using gene expression profile.Results: The B cells closely related module was identified and five genes including ARID5A, CLEC2B, MICAL1, MZB1 and RAPGEF1 were ultimately selected to establish the prognostic signature for calculating risk scores of PAAD patients. Kaplan-Meier curves presented a worse survival in the high-risk patients (p<0.05) and the area under the Receiver operating characteristic (ROC) curve of risk score for 1-year and 3-year survival were 0.78 and 0.80 based on the training set. Also, similar results were verified in the validated and combined sets. Interestingly, low-risk group presented significantly elevated immune, stroma scores and proportion of B cells and associations between these five genes and B cells were identified by using multiple methods including ssGSEA, MCPcounter and EPIC. Conclusions: This is the first attempt to study a B cells related prognostic signature, which is instrumental in exploration of novel prognostic biomarkers in PAAD.