Ascorbic acid potentiates As₂O₃-mediated cell death in multiple myeloma cell lines.

Cells were cultured in the absence (■) or the presence of As₂O₃ (2 μM; ░), AA (100 μM; ▨), or As₂O₃+AA (▪). Viability was assessed as described in “Materials and methods” after 48 hours for the 8226/S, 8226/Dox40, and U266 cell lines or after 72 hours for the U266/Bcl-x_L cell line. Data are presented as the mean ± SD of at least 4 experiments per cell line. *Means of the As-treated cells are lower than those of the control cells and of the AA-treated cells (P < .002). **Means of the As+AA-treated cells are lower than of the As-treated cells (P < .02). #Means of the As-treated cells are lower than of the control cells and of the AA-treated cells (P < .01). ##Means of the As+AA-treated cells are lower than of the As-treated cells (P < .02).