Using two breast cancer cell lines, MCF-7 and MDA-MB 231, genistein influenced H3 and H4 histones on H3K27me3, H3K9me3, H3K4me3, H4K8ac, and H3K4ac marks, on six genes (EZH2, BRCA1, ERa, ERb, SRC3, and P300). This evidence concerns the gene EZH2 and breast cancer.