Copy number-associated gene expression changes were confirmed for 9 out of the 13 (69.2%) genes (ALPK2, CYP3A4, ENAH, ERBB2, HHIPL2, MMP9, PERLD1, PTPRA, and OSMR) thereby validating the results from the integrated microarray analysis and highlighting these genes as potential biomarkers for gastric cancer. Here, CYP3A4 is linked to gastric cancer.