Increased Expression Correlates with Poor Prognosis and Immune Infiltration in Stomach Adenocarcinoma.

Background: Previous studies have described that the gene is involved in the occurrence and development of various tumor entities. However, little is known about its expression and relevance in stomach adenocarcinoma (STAD). The aim of this study was to bioinformatically analyze the role of in STAD, followed by patient tissue sample analyses.

Materials And Methods: expression levels in STAD and normal gastric tissues were analyzed in the Cancer Genome Atlas and Gene Expression Omnibus databases; results were verified in fresh clinical STAD specimens on both gene and protein expression levels. expression correlated with survival parameters by Kaplan-Meier and multivariate Cox regression analyses. The top genes co-expressed with were identified by gene set enrichment analysis (GSEA) using the clusterProfiler package in R. Furthermore, the R package (immunedeconv), integrating the CIBERSORT algorithm, was used to estimate immune cell infiltration levels in STAD.

Results: gene and sec23a protein expression were both significantly upregulated in STAD, and this correlated with the pT stage. Moreover, high expression was associated with poor disease-free and overall survival of STAD patients. Cox analyses revealed that besides age and pathologic stage, expression is an independent risk factor for STAD. GSEA indicated that was positively associated with ECM-related pathways. In the CIBERSORT analysis, the level of negatively correlated with various infiltrating immune cell subsets, including follicular helper T cells, Tregs, activated NK cells and myeloid dendritic cells. Finally, the expression levels of immune checkpoint-related genes, including HAVCR2 and PDCD1LG2, were significantly increased in the high expression group.

Conclusions: We observed the significantly upregulated expression of in STAD, an association with disease progression, patients' prognosis and infiltrating immune cell subsets. Thus, we propose as an independent prognostic factor with a putative role in immune response regulation in STAD.