In this study we aimed to investigate the impact of combinatorial SFN and WA on MCF-7 estrogen receptor-positive (ER (+)) and MDA-MB-231 ER (−) breast cancer cell proliferation in conjunction with their role in the epigenetic gene expression of DNMT1, DNMT3A, DNMT3B and HDAC1. The gene discussed is DNMT3B; the disease is breast cancer.