ERBB2 and neoplasm: The proportion of methylated RASSF1A, GSTP1, and APC genes was significantly greater in the HER2/neu-positive than in the HER2/neu-negative tumor group; no significant differences in methylation status were detected for TWIST, NES1, RARβ2, and CCND2. Among the eight biomarkers studied, CDH1 showed predominance of methylation status in HER2/neu-negative tumors by univariate analysis (Table 10).