Curcumin prevents nuclear localization of NF-κB and STAT3 in bone marrow CD138⁺ multiple myeloma cells. Enriched CD138⁺ cells (1 × 10⁵/0.1 mL) from bone marrow aspirates of multiple myeloma patients were cultured in the absence or presence of curcumin (50 μM) for 2 hours, fixed on slides by cytospin centrifugation, and immunostained for NF-κB (A). Enriched CD138⁺ cells (2 × 10⁶ cells) from bone marrow aspirates of multiple myeloma patients as indicated were cultured in absence or presence of curcumin (50 μM) for 2 hours and then tested for NF-κB activity in the nuclei by electrophoretic mobility shift assay as described in “Patients, materials, and methods” (B). Enriched CD138⁺ cells (1 × 10⁵/0.1 mL) from bone marrow aspirates of multiple myeloma patients were cultured in the absence or presence of curcumin (50 μM) for 1 hour and then fixed on slides by cytospin centrifugation and immunostained for STAT3 as described in “Patients, materials, and methods” (C). Red stain indicates the specific staining for NF-κB or STAT3 as indicated, whereas blue stain indicates the relative position of the nuclei in the corresponding view. Original magnification, × 200.