Figure 3

(A) Effect of Atiprimod on MM cell lines. Upper panel: MM-1, U266-B1, OCI-M5, MM-1R, and RPMI-8266 (5 × 10⁴) cells were incubated in RPMI 1640 supplemented with 10% FCS with or without increasing concentrations of Atiprimod for 72 h. Cells were harvested and their metabolic activity and viability were determined using the MTT assay. Data are presented as the mean±standard deviation of optical density (OD) measurements of six wells. Lower panel: MM-1, U266-B1, OCI-M5, and MM-1R cells (5 × 10⁴) were incubated with 4 μ M Atiprimod for 24, 48, and 72 h. Cells were harvested and their metabolic activity and viability were determined using the MTT assay. Data are presented as a percent of OD of cells cultured without Atiprimod at the same time point (control). (B, C) Effect of IL-6, VEGF, and BM stroma on Atiprimod-induced inhibition of U266-B1 cells. These cells were cultured alone or with adherent KM102 stroma cells, with or without either IL-6 (B) or VEGF (C) at 5 ng ml⁻¹, and in the presence of increasing concentrations of Atiprimod. After 72 h, U266-B1 cells were harvested and analysed using the MTT assay. The data are presented as the mean±standard deviation of OD measurements of five wells.