Differential Expression of COL1A1, COL1A2, COL6A3, and SULF1 as Prognostic Biomarkers in Gastric Cancer

Background: Gastric cancer (GC) is among the most prevalent cancers globally. As such, there is a need to explore the mechanism underlying its pathogenesis and identify potential biomarkers for its prognosis. Methods: ONCOMINE was used to screen differentially expressed genes between GC and normal gastric mucosa. GEPIA was used to analyze the expression and correlation of candidate genes in tumor node metastasis (TNM) stage. STRING was used to construct protein interaction network. Kaplan-Meier plotter was used to analyze survival. TIMER was used to evaluate the association between candidate genes and immune cell infiltration. Results: From the ONCOMINE database, we found COL1A1, COL1A2, COL6A3, and SULF1 genes were significantly upregulated in stomach adenocarcinomas. There was a considerable correlation between the expression of COL1A1 (p = 0.029), COL1A2 (p = 0.004), COL6A3 (p = 0.002), SULF1 (p = 0.001), and the TNM stage. COL1A1 was positively correlated with ERBB2 (R = -0.037, p = 0.46), while the other three genes were negatively correlated with ERBB2 (p > 0.05). The Kaplan-Meier plotter showed that low transcriptional levels of COL1A1 (p = 0.0020), COL1A2 (p = 0.0015), COL6A3 (p = 0.0015), and SULF1 (p = 0.0016) in gastric cancer patients were remarkably related to longer overall survival. In addition, there was a close relationship between chemokine expression and infiltration of the six immune cell types: B cells, macrophages, CD4+ T cells, CD8+ T cells, dendritic cells, and neutrophils, implying that the genes acted as indicators of both prognosis and immune status. Conclusion: Our findings implicate COL1A1, COL1A2, COL6A3, and SULF1 as candidate biomarkers for the prognosis of gastric cancer.