The Expression and Prognostic Value of NOX4 in Gastric Cancer

Background: Gastric cancer (GC) is one of the most common malignant tumors worldwide which threaten the health of human. A lot of work has been done in tumor pathogenesis in recent years, while modest progress in diagnosis and treatment of gastric cancer have been made. Methods: Multiple databases including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were explored to identify the expression pattern of Nicotinamide Adenine Dinucleotide Phosphate Oxidase 4 (NOX4), the main source of reactive oxygen species, in gastric cancer. We also analyzed the correlation between the expression level of NOX4 and gastric cancer patients’ clinical features. The prognostic value of NOX4 was explored in TCGA and K-M Plotter. Last, we utilized TCGA and DAVID databases to uncover the underlying molecular mechanisms of NOX4 with TCGA and DAVID databases. Results: We found that NOX4 was upregulated in tumors compared with adjacent non-tumor tissues and overexpression was correlated with tumor invasion and TNM stage in gastric cancer. Furthermore, NOX4 level could be an independent prognostic marker for GC, unacted on the choice of therapy or HER2 expression. Besides, we investigated the potential mechanisms of NOX4 in gastric cancer. Conclusions: Our findings proved that NOX4 may be a new prognostic factor or therapeutic marker for gastric cancer