Effect of curcumin on cytotoxicity of vincristine and melphalan in human MM cells.

Curcumin potentiates the cytotoxic effect of vincristine and melphalan in human multiple myeloma cells. Multiple myeloma cells (10 000/0.1 mL), U266 (panel A), RPMI 8226 (panel B), MM.1 (panel C), and MM.1R (panel D) were incubated with either medium, vincristine (50 μM), or melphalan (10 μM) in the absence (black bars) or presence (hatched bars) of curcumin (10 μM) for 24 hours, and then the cell viability was determined by the MTT method as described. Values are means (± SDs) of triplicate cultures.