Figure 1. CHR-3996 inhibits the proliferation of myeloma cells and induces apoptosis.

A. A panel of myeloma cell lines were treated with a range of concentrations of CHR-3996 (i), SAHA (ii), or Sodium (Na) Valproate (iii) for 48 hours. The proliferation of the cells was monitored by metabolic activity (WST-1 assay) and is shown as a percentage of untreated cells. The LC₅₀ for each cell line is shown in Supplementary Table 1. B. H929 and RPMI-8226 cells were treated with CHR-3996 (250 nM and 100 nM respectively) for 8, 24, or 48 hours. Apoptosis was analysed by Annexin-FITC/propidium iodide (PI) staining and analysis by flow cytometry (AnnexinV positive is defined as early apoptotic, AnnexinV and PI positive as late apoptotic) and by trypan blue exclusion. C. Primary CD138⁺ plasma cells from three patients were treated with a range of concentrations of CHR-3996 and the proliferation measured by WST-1 assay. D. Primary patient CD138⁺ plasma cells were treated with either 50 or 100 nM CHR-3996 over a time-course of 48 hours. The percentage of cells undergoing apoptosis was determined by binding of AnnexinV and PI followed by analysis by flow cytometry. Results from a representative patient are shown.