Fig. 3. Sulforaphane blocks TPA-induced NF-κB activation in MCF-7 cells. Cells were treated with sulforaphane in the presence of TPA. Following 3 h incubation, nuclear extracts were prepared as described in the Materials and Methods. NF-κB/AP-1 DNA binding was analyzed by EMSA, as described in Materials and Methods (A). Nuclear/cytoplasm extracts were subjected to western blot analysis (B, C). Cell extracts were prepared from MCF-7 cells with TPA for 15 min in the absence or presence of sulforaphane, and subjected to western blotting (D).