GSTM2 and breast cancer: Methylation also varied according to clinicopathologic characteristics, with higher tumor grade being strongly correlated with hypermethylation of such genes as GSTM2, EPHX1, and BCR, and larger primary tumor size correlated with hypermethylation of GSTM2, PYCARD, MYCL2, and MT1A. Methylation of several of these genes has been noted previously in breast cancer [37],[40]-[43].