ESR1 and breast neoplasm: For these analyses we chose two GEO series: GSE2225 [33] (a dataset of 18 samples in which MCF7 cells overexpressing aromatase were treated with estrogen, the E2 precursor testosterone, or vehicle) as an example of a dataset that strongly reflects the effects of estrogen receptor pathway activation (Fisher q = 3.67 × 10-6; K-S q = 0.00766), and GSE21653 [34] (a dataset of 266 primary breast tumors) as an example of a dataset that more weakly reflects the effects of estrogen receptor pathway activation (Fisher q = 0.319; K-S q = 0.198).