Well established examples for the role of promoter methylation in the prediction of chemosensitivity are a) MGMT methylation for the prediction of response to alkylating agents such as temozolomide in glioblastoma multiforme [6], [7], b) FANCF methylation as predictor for platinum sensitivity in ovarian cancer [8] and c) CHFR methylation as predictor for taxane sensitivity in gastric [9], cervical [10] and possibly also colon cancer [11]. This evidence concerns the gene MGMT and glioblastoma.