In addition, loss of DNA mismatch repair (MMR) gene hMLH1 via full hypermethylation of the hMLH1 promoter [150] is highly correlated with the ability of arresting cell death and cell cycle after DNA damage induced by chemotherapy and poor survival prediction for cancer patients [151], hence plays a role in drug resistance in ovarian [152] and breast cancers [153]. Here, MLH1 is linked to breast cancer.