In the breast cancer cell line MDA-MB-453, treatment with calcium, cadmium, or a synthetic agonist also increased the expression of ESRRB-regulated genes that was blocked by the antagonist, enhanced ESRRB nuclear localization, increased the recruitment of RNA polymerase 2 to estrogen-related receptor response elements (ERRE), enhanced cell stemness and proliferation pathways, and induced the expression of estrogen receptor alpha (ESR1 or Erα). This evidence concerns the gene ESRRB and breast cancer.