A low concentration of piceatannol (50 nM) was reported to upregulate the expression of the proto-oncogene c-Myc, which was dependent on progesterone receptor and estrogen receptor, resulting accelerated proliferation of MCF-7 breast cancer cells, whereas at higher concentration (25–100 μM), it was anticarcinogenic to the same cell line. This evidence concerns the gene ESR1 and breast cancer.