The 10058-F4 induced apoptosis in c-MYC–expressing primary myeloma cells and myeloma cell lines irrespective of IG-MYC translocations. (A) Expression of c-MYC and L-MYC mRNA and protein was evaluated in 6 human myeloma cell lines by quantitative RT-PCR and immunoblotting. The relative quantification (RQ) of mRNA levels was calculated using the δ δ C_t method with GAPDH as housekeeping gene. All mRNA values were compared with MYC mRNA in the KJON cell line, which was set to 1. (B) The effect on cell viability was evaluated by annexin-V FITC and propidium iodide staining after treatment by 10058-F4 for 48 hours. Examples of flow cytometry dot-plots are found in supplemental Figure 1. (C) Expression of MYC mRNA in 11 CD138⁺ primary myeloma cells. Levels of MYC in IH-1 and KMS-12-BM cell lines are included for comparison. For patient MM8, cDNA was not available. (D) Cell viability of 12 patient samples treated for 72 hours with increasing amounts of 10058-F4. Error bars represent SD of triplicate (A,C) or duplicate measurements (B,D).