The expression of POSTN and immune cell infiltration are prognostic factors of lung adenocarcinoma.

The objective of this study is to identify useful prognostic factors of lung adenocarcinoma (LUAD) by evaluating the changes of periostin (POSTN) expression activity and immune cell infiltration using public data repositories. The gene and protein expressions of POSTN in LUAD were collected and analyzed from Ualcan and Human Protein Atlas online database. The cell infiltration data of immune cells in LUAD patients were retrieved and processed using the TIMER tool. Cox regression analysis was employed to screen and characterize prognosis factors, Kaplan-Meier Plotter was used to analyze the survival curve of LUAD patients, and receiver operating characteristic curve was used to calculate the relationship between temporal POSTN expressions and the prognosis of LUAD. The expression activity of POSTN in LUAD was higher than that in normal tissues. With the exception of B cell which showed opposite correlationship, the infiltration of most immune cells, namely CD8+ T cells, macrophages, neutrophils, and dendritic cells, was positively correlated with the POSTN expression activity. Together, our investigation suggested that the POSTN expression activity and B-cell infiltration were the prognostic factors of LUAD. In addition, the 1-year negative predictive value of the POSTN expression activity for overall survival, disease-free survival, and progression-free interval was 0.902, 0.926, and 0.838, respectively. Along with decreased B-cell infiltration, the elevated expression of POSTN is an important factor of LUAD prognosis.