Bortezomib exerts cytotoxicity in HL B-cell lines. HL B-cell lines L591 and L428 were treated with increasing amount of bortezomib. (A) After 48 hours PARP was detected in nuclear extracts by mouse anti-PARP antibody. DNA of approximately 5 × 105 cells was loaded with 10% Ficoll onto a 1.8% agarose gel and visualized with ethidium bromide under UV light. (B) After 24 hours nuclear extracts were prepared and analyzed for NF-κB binding activity. (C) NF-κB binding activity was determined using a phosphoimager (molecular imager; Bio-Rad, Hercules, CA). Signal intensities were quantified and are presented as percentage of the mean levels in untreated cells. The experimental values represent mean ± SD values from 3 individual experiments performed. (D) Viability was determined by XTT assay after 48 hours and expressed as mean ± SD values from 3 individual experiments performed in triplicate.
