Nsc 95397

MCF-7 and MDA-MB-231 cells were obtained from the American Type Culture Collection (Manassas, VA). Cells were cultured in DMEM (Invitrogen, Life Technologies, Carlsbad, CA) supplemented with 10% FBS, 2mM L-glutamine, and 1% penicillin-streptomycin-neomycin. MCF-7 cells were stimulated with 1.32 ng/ml phorbol 12-myristate 13-acetate (PMA) (Sigma-Aldrich, St Louis, MO) or 5 ng/ml recombinant TGF-β1 (R&D Systems, Minneapolis, MN) for 60 h, as previously described [28 ]. 0.65 nM triptolide (Santa Cruz, Dallas, TX) and 1 μM NSC 95397 (Santa Cruz) were used for inhibitor experiments. Forward transfection reactions were performed for 6 h with 50 nM human DUSP1 siRNA (sc-35937), DUSP4 siRNA (sc-38998), DUSP6 siRNA (sc-39000), 20 nM PKC-θ siRNA (sc-36252), and 10 nM MOCK siRNA (sc-36869) (Santa Cruz) using Lipofectamine 2000 (Invitrogen).

PAC, ATRA, BMS753, LG100268, BMS195614, and verapamil were purchased from Sigma-Aldrich (St. Louis, MO, USA). UVI3003, 3,5-bis(trifluoro-methyl)pyrazole (BTP-2), and NSC-95397 and antibodies for phospho-MAPK kinase (p-MEK)-1/2, p-extracellular signal-regulated kinase- (pERK-) 1/2, ERK-1/2, p53, cyclin B1, caspase-3, and β-actin were supplied by Santa Cruz Biotechnology (Dallas, TX, USA). Antibodies for caspase-8 and caspase-9 were procured from Cell Signaling Technology (Danvers, MA, USA).