ESR1 and breast carcinoma: Indeed, FOXA1 expression in breast cancers is predictive of luminal ERα-positive disease, and co-reexpression of ERα, FOXA1 and GATA3 has been shown to be able to reprogramme ER-negative breast cancer cell lines to regain hormonal sensitivity.41 In addition to promoting mammary luminal phenotype, FOXA1 might also have a more direct role in repressing the basal breast cancer phenotype.