In the Kaplan–Meier Plotter database21, high PRR11 mRNA levels were also associated with a shorter relapse-free survival (RFS) of ER+/HER2− breast cancers treated with endocrine therapy (HR = 3.85; 95% CI, 1.95–7.59; Fig. 1d), but this association was not present in patients with HER2+ or triple-negative breast cancer (TNBC; Supplementary Fig. 1a). This evidence concerns the gene ESR1 and breast cancer.