Figure 3.

DPP8 as a target of myeloma therapy. (A) 1.0 × 10⁵ MM.1 S cells were cultured with 20 nM DPP8 siRNAs (left) or DPP9 siRNAs (right) for 72 hours. Cell number was estimated by a colorimetric assay using WST-1 reagent (n = 6). (B) DPP8 gene expression of CD38 + bone marrow cells in healthy volunteers (HV) (n = 5) was compared to those in Waldenstrom’s macroglobulinemia patients (WM) (n = 10) or in multiple myeloma (MM) patients (n = 12) based on a dataset record GDS2643. (C) 1 × 10⁶ MM.1 S cells were cultured with 1G244 (50 µM) for 0–48 hours. The full length (FL) and cleaved form (CL) of PARP or caspase-3 were detected by Western blot analysis. β-Actin was used as a loading control. Full-length blots are presented in Supplementary Fig. 3. (D) 1.0 × 10⁶ MM.1 S (left) or KMS-5 (right) cells were cultured with 1G244 (50 µM) with or without pan-caspase inhibitor, Z-VAD-FMK (100 µM) for 24 hours. Non-viable cells were estimated by a flow cytometric analysis using 7-AAD reagent (n = 6). The data are representative of three separate experiments except (B) and presented as the mean ± SD in (A,B,D).