Intense Uptake of Liposomal Curcumin by Multiple Myeloma Cell Lines: Comparison to Normal Lymphocytes, Red Blood Cells and Chronic Lymphocytic Leukemia Cells

Abstract

Background/Aim: Curcumin is being widely investigated for its anticancer properties and several studies in the literature suggest that curcumin is distributed to a higher degree in cancer cells compared to normal cells. The goal of this study was to investigate the disposition of curcumin in the form of Lipocurc™ in multiple myeloma (MM)-causing plasma cell lines and B-lymphocytes from healthy individuals and compare the uptake to previously published data for red blood cells (RBCs), peripheral blood mononuclear cells (PBMCs) from healthy individuals and PBMCs from patients with chronic lymphocytic leukemia (CLL-cells). Materials and Methods: Two MM-producing cell lines were studied: RPMI-8266, an IgG lambda cell line, and NCL-H929, an IgA kappa line. The distribution of liposomal curcumin and its metabolism to the major stable metabolite tetrahydrocurcumin (THC) were measured in vitro in the cell lines and B-lymphocytes. The cells were incubated in plasma protein-supplemented media with liposomal curcumin (Lipocurc™) for 15 min at 37°C and the levels of curcumin and THC in cells and medium were determined by liquid chromatography tandem mass spectrometry. Results: Extremely intense uptake was seen in both MM lines compared to that in B-lymphocytes and previously published data in RBCs, PBMCs and CLL cells. The levels of curcumin in RPMI-8266 and NCI-H929 cells were 14,225±847 and 12,723±500 pg/10⁶ cells compared to 19±5,587±86 and 3,122±166 pg/10⁶ cells in RBCs, PBMCs and CLL cells, respectively. Conversion of curcumin to THC was greatest in PBMCs, considerably less in CLL cells and minimal or absent in B-lymphocytes and MM cell lines. Conclusion: The extremely intense uptake of curcumin (as Lipocurc™) in both MM lines further suggests that Lipocurc™ should be investigated in the treatment of patients with this disease.