Consistently, a significantly marked decrease of total DNMTs activity was detected in MCF-7 and MDA-MB-231 cells treated with EGCG or 5-aza-dC (p < 0.01) (Figure 6C,D), which suggested that EGCG can reactivate the SCUBE2 gene in human breast cancer cells by reducing DNMT activity and DNA methylation. Here, DNMT1 is linked to breast cancer.