FIG. 2.

Biochanin A (BCA) is more effective than other phytoestrogens and steroids at increasing the survival of CCFSTTG1 and U87MG cells and reducing p75^NTR levels in the presence of ibuprofen. MTT assay and p75^NTR Western blot analysis of CCFSTTG1 (A and C) or U87MG (B and D) cells treated with ibuprofen (2 mM) for 24 h followed by ibuprofen (2 mM) + 0, 10, 20, 40, 60, 80, or 100 μM Biochanin A, genistein, formononetin, or daidzein for an additional 24 h (left panels of A and B), or by ibuprofen (2 mM) + 0, 10, 20, 40, 60, 80, or 100 nM dexamethasone, β-estradiol, progesterone, or DHT for an additional 24 h (right panels of A and B). Data are presented as mean cell survival ± standard error of the mean (SEM), normalized to ibuprofen-treated cells only, with ** and *** indicating p < 0.01 and 0.001, respectively, as compared to ibuprofen only-treated cells. For Western blots (C and D), cell lysates (40 μg) were resolved by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). Immunoblots were stripped and reprobed for β-actin to ensure equal loading, and the A875 melanoma cell lysates were used as a positive control for p75^NTR. Respective quantifications (from two independent experiments) of p75^NTR expression are shown below for every cell type and normalized to levels in ibuprofen-treated cells.