Interestingly, RNF208 expression was markedly induced by E2 treatment, similar to other ERα-responsive genes, such as FOXOM1 and GREB1 (Fig. 2b), and siRNA-induced ESR1 knockdown attenuated the E2-induced expression level of RNF208 in T47D cells (Fig. 2c), indicating that RNF208 expression may depend on ERα expression in luminal breast cancer cells. This evidence concerns the gene GREB1 and breast carcinoma.