ESR1 and breast cancer: Next, we analyzed the correlation between MCM3 mRNA expression and outcome in a large cohort of 1802 endocrine-treated ER+ breast cancer patients that received adjuvant endocrine therapy, ER+ breast cancer patients that did not receive adjuvant therapy (n = 504 for PFS and n = 250 for OS) as well as ER− patients (n = 249 for PFS and n = 104 for OS) available through KM plotter 2014 version14.