Effect of SN50 on NF-κB activity in MM cells.

SN50 down-regulates constitutive and induced NF-κB activity in MM cells. DNA-binding activity of the transcriptional factor NF-κB was quantified in MM.1S cells pretreated with or without SN50 (20 μM) for 1 hour, and then treated with or without TNF-α (50 ng/mL) for 4 hours. The DNA binding activity of NF-κB in MM.1S cells was quantified by ELISA with the use of the Trans-AM NF-κB p65 Transcription Factor Assay Kit, according to the manufacturer's instructions. Values (mean ± SD) were normalized for cellular protein content. Data are representative of 3 experiments. Constitutive NF-κB DNA-binding activity in MM.1S cells was significantly inhibited by SN50. Moreover, SN50 inhibited NF-κB activation induced by TNF-α.