GPX7 and neoplasm: We detected GPX7 promoter hypermethylation (> 10% DNA methylation level) in 55.6% (25/45) of tumor tissue samples (range: 11%–65%) while only 13.3% (6/45) of normal gastric tissues showed > 10% methylation levels (range: 11%–24%) (Fisher exact test, p < 0.0001, Table 1).