ALPK2 and gastric cancer: 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.