Figure 4
Phospho-ibuprofen inhibited NF-κB signaling in breast cancers. (A) Left panels: NF-κB-DNA binding was determined by electrophoretic mobility shift assay (EMSA) in nuclear fractions of MCF-7 cells treated with or without phospho-ibuprofen (P-I). 0, control nuclear fraction incubated with 100-fold molar excess of specific (+S) or nonspecific (+NS) unlabeled oligonucleotide containing the consensus sequence of NF-κB. IC50, concentration that inhibits cell growth by 50%; NAC, N-acetyl-cysteine. Right panels: Immunoblots of B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia 1 (Mcl-1) from MCF-7 cells treated with or without P-I as indicated. Representative images (200×) of immunohistochemistry staining of activated NF-κB in (B) MCF-7 and (D) MDA-MB-231 xenografts (as in Figure 1) and quantification results are shown. Immunoblots of Bcl-2 and Mcl-1 from the lysates of (C) MCF-7 and (D) MDA-MB231 xenografts (as indicated) are shown. Lipo-P-I, liposome-encapsulated phospho-ibuprofen. #P < 0.05; *P < 0.001. Loading control, β-actin.