ESR1 and breast cancer: Subgroup analyses indicated that high mRNA expression of MGMT was significantly correlated to longer survival in ER positive- (DFS: HR=0.47, p=0.037 OS: HR=0.39, p=0.0084) (Fig. 1F and 1I), but not in ER negative- BC (DFS: HR=1.19, p=0.736 OS: HR=0.98, p=0.97) (Fig. 1G and 1J).