SELP can affect the immune microenvironment of gastric cancer and is associated with poor prognosis

The tumor microenvironment (TME) plays a crucial role in the occurrence and progression of gastric cancer. However, it is still unclear how the immune and stromal components of the TMEs are modulated. In this study, we have applied the ESTIMATE algorithm to calculate the number of immune and stromal components in 410 STAD cases from the Cancer Genome Atlas (TCGA) database. COX regression analysis and protein-protein interaction (PPI) network construction were used to analyze differentially expressed genes (DEGs). P-selectin (SELP) was identified as a predictor by cross-analysis of univariate COX and PPI. After verifying the clinical significance of SELP in this study, we performed immune infiltration analysis and identified 54 immunomodulators associated with SELP using public data. Immunomodulation associated with gastric cancer prognosis was confirmed by LASSO regression, and previous results were further validated using single-cell data. Finally, we have verified that SELP promoted EMT in gastric cancer cells. In conclusion, we demonstrated that SELP may affect the biological phenotype of gastric cancer with its immune microenvironment.