Myeloma cells exhibit glucose dependence and overexpression of GLUT4, GLUT8, and GLUT11 mRNAs relative to NBLs. (A) Primary myeloma cells, NBLs, and 4 MM cell lines were cultured in medium containing 0 or 5mM glucose for 48 (NBL, MM cell lines) or 72 (MM patient) hours. Cell viability was determined by flow cytometric analysis of annexin V/DAPI staining and normalized to 5mM samples. Data are mean ± SEM (n = 2 for MM cell lines and NBL, n = 1 for MM patient sample). (B) MM cell lines were cultured in various glucose concentrations for 72 hours. Viable cell quantities were determined by MTS assay (represented by absorbance at 490 nm) and normalized to 5mM samples. U266 cells (C) and normal PBMCs (D) were cultured in 11 or 0.5mM glucose-containing medium for 48 hours in the presence of the indicated concentrations of doxorubicin. Cell death was determined by DAPI staining. (E) Expression of GLUTs 1 to 12 was determined in 9 myeloma cell lines and NBLs (red bars) by quantitative real-time RT-PCR. Relative quantification (RQ) is displayed and normalized to the MM.1S cell line. For GLUT4, GLUT8, and GLUT11, comparisons between each MM cell line and NBLs exhibit 1-tailed P values less than .05, with the exception of GLUT4 expression in the OCIMY1 cell line. (B-E) Data are mean ± SEM (n ≥ 3). *P < .05. **P < .01. ***P < .005.