Identification of Potential Biomarker in Gastric/Stomach Cancer using Microarray Based Expression Network Analysis through in silico Tools

Stomach cancer is the fifth most common cancer type in the world, and Millions of deaths are reported every year. Many factors are involved in stomach cancer, like age, gender, environmental factors, and heredity. MicroRNAs (22bp long), known post-transcriptional regulators, play an important role in regulating protein-coding genes. Abnormal expression of miRNA causes tumor development. This study aims to identify novel biomarkers in stomach cancer using different in silico tools. Stomach cancer-related microarray datasets (GSE79973, GSE118897, GSE224056, GSE84787) maintained in GEO at NCBI were utilized. The data normalization was performed through R code utilizing R Studio. Used DAVID for gene ontology, Biological and Molecular pathways of differentially expressed genes. The protein-protein interaction (PPI) network analysis was then performed utilizing MCODE and Cytohubba analysis from CYTOSCAPE software. Finally, some genes showed vital gene networks involved in Stomach Cancer. All these genes were selected on the basis of their higher-level expression, which was further validated from GEPIA. Concluding this study, several key genes were identified as potential biomarkers in stomach cancer, showing their involvement in cytokine-cytokine receptor and chemokine signalling interaction pathways after survival analysis.