Celastrol inhibits TNF-induced NF-κB-regulated gene products. (A) Celastrol inhibits the expression of antiapoptotic gene products such as survivin, IAP1, IAP2, Bcl-XL, Bcl-2, and c-FLIP. KBM-5 cells (2 × 106/mL) were left untreated or were incubated with 2.5 μM celastrol for 6 hours and then treated with 1 nM TNF for different amounts of time. Whole-cell extracts were prepared, and 30 μg of the whole-cell lysate was analyzed by Western blotting using antibodies against IAP1, IAP2, Bcl-xl, Bcl-2, cFLIP, and survivin as indicated. (B) Celastrol inhibits COX-2 and cyclin D1 expression induced by TNF. KBM-5 cells (2 × 106/mL) were left untreated or were incubated with 2.5 μM celastrol for 6 hours and then treated with 1 nM TNF for different times. Whole-cell extracts were prepared, and 30 μg of the whole-cell lysate was analyzed by Western blot analysis using antibodies against COX-2 and cyclin D1. (C) Celastrol inhibits VEGF and MMP-9 expression induced by TNF. KBM-5 cells (2 × 106/mL) were left untreated or were incubated with 2.5 μM celastrol for 6 hours and then treated with 1 nM TNF for different times. Whole-cell extracts were prepared, and 30 μg of the whole-cell lysate was analyzed by Western blot analysis using antibodies against MMP-9 and VEGF. Data are for a representative experiment of 3 independent experiments showing similar results.
