Our data are in accordance with previous reports showing altered methylation patterns of a panel of genes in ovarian cancer, including genes encoding RASSFIA, HIN-1, APC, BRCA1, CASP8, CDH13, CDKN2A, CDKN2B, GSTP1, MLH1, PTEN, RASSF1, TIMP3, sFRP4, sFRP5, CCND2 and TP73, which had various promoter methylation extents above the 30% threshold[9,22,23]. Here, PTEN is linked to ovarian cancer.