We detected the methylation status of the CpG islands of these genes in the constructed cell lines and determined that the LDH, DLD and CaM genes were demethylated at the promoter -2325, -1885 and -276 sites, respectively, and the RanGAP gene was highly methylated at the promoter -570 and -170 sites, consistent with the high expression of the LDH, DLD and CaM genes and the low expression of the RanGAP gene in gastric cancer tissues with cagA+H. The gene discussed is S100A8; the disease is gastric cancer.