Abstract

We identified genes that affect the prognosis of early-onset and conventional gastric cancer and established a clinical prognostic model in gastric cancer. Differentially expressed genes in gastric cancer were identified using Limma analysis from GSE84426 dataset. Weighted gene co-expression network analysis of age-related hub genes in GSE84426 dataset was performed. Venn diagram of the intersecting genes was identified between differentially expressed genes and hub genes. Expression and prognosis of intersection genes were analyzed in the GSE84426 and The Cancer Genome Atlas-gastric cancer datasets. Signaling pathways of the intersecting genes and their correlation with immune cells were analyzed using gene set enrichment analysis, estimating the proportions of immune and cancer cells and estimation of stromal and immune cells in malignant tumor tissues using expression data. Finally, a prognostic model was established using a nomogram in The Cancer Genome Atlas-gastric cancer dataset. Overall, 1021 differentially expressed genes in gastric cancer were identified from the GSE84426 dataset in patients with gastric cancer aged <45 and ≥45 y which were analyzed using weighted gene co-expression network analysis. Based on the correlation between gene significance and module membership where we screened purple and green modules. Regulator of G protein signaling 4 and neuronal regeneration related protein were identified using Venn diagram as the intersection genes between differentially expressed genes and hub genes identified by weighted gene co-expression network analysis. Regulator of G protein signaling 4 and neuronal regeneration related protein were noted to be overexpressed in gastric cancer in patients aged <45 y in GSE84426 dataset compared with the normal tissue. Prognostic value of the overexpression of regulator of G protein signaling 4 and neuronal regeneration related protein were significantly better than that of the underexpression noted in the Cancer Genome Atlas gastric cancer dataset. Regulator of G protein signaling 4 and neuronal regeneration related protein has significant correlation with stromal score, immune score, estimation of stromal and immune cells in malignant tumor tissues using expression score among cells like cluster of differentiation 4 and 8, neutrophils, and macrophages. Both regulator of G protein signaling 4 and neuronal regeneration related protein were overexpressed in early-onset gastric carcinoma and impacted the prognosis of gastric cancer.