Evaluation of Albuminated Curcumin as Soluble Drug Form to Control Growth of Cancer Cells in Vitro

Curcumin (Curc) is well known for its anticancer activity, but its poor solubility in aqueous medium is a major concern for little therapeutic outcome. Therefore, the effort to improve its bioavailability is a major research interest. The current study aimed at conjugation of Curc to serum albumin (Alb) to increase aqueous solubility of the former without affecting its drug action on cancer cell lines and primary cells in culture. Conditions for preparation of albumin-curcumin (Alb-Curc) conjugate were standardized to obtain pure and stable drug. The product was obtained in sufficient quantity to test its effect on cells in culture at different doses. Briefly, the conjugate was prepared by mixing Curc dissolved in DMSO with the Alb dissolved in phosphate buffered saline; conjugate was purified by gel filtration chromatography and was analyzed using UV-Vis spectroscopy for characteristic peaks of both molecules. The conjugate was added to culture medium to identify the effect of conjugate on cell cycling and apoptosis. Albuminated curcumin that showed 100-fold higher solubility than free Curc was stable and inhibitory to proliferation, induced cell cycle arrest and apoptosis. The conjugate showed apoptotic effects on endothelial cells indicating its anti angiogenic property. Primary fibroblast growth was also inhibited but at the higher dose. The in vitro results suggest that Alb-Curc which is free of insoluble native drug may find application in cancer therapy after appropriate in vivo evaluations.