This regulation of VEGFA by ZEB1 was demonstrated not only in cells representing basal breast cancer cells (eg, MDA-MB-231; estrogen-receptor negative) but also in cells representing luminal breast cancer cells (eg, MCF-7; estrogen-receptor positive; S3 Fig), suggesting that ZEB1-induced angiogenesis may be a general mechanism in this disease. This evidence concerns the gene ESR1 and breast cancer.