Earlier studies of other cancer histologies have identified therapeutically relevant DNA methylation biomarkers in the promoter regions of MGMT, increased methylation of which is beneficial for the response to alkylating therapeutic agents and ionizing radiation in glioblastoma and colorectal cancer, and of SLFN11, methylation of which has been associated with resistance to DNA damaging agents in a variety of cancer categories [16–22]. This evidence concerns the gene MGMT and cancer.