Invertible micellar polymer nanoassemblies target bone tumor cells but not normal osteoblast cells

Aim: To demonstrate the capability of the invertible micellar polymer nanoassemblies (IMAs) to deliver and release curcumin using the recently discovered mechanism of macromolecular inversion to treat bone tumor cells. Materials & Methods: The effect of IMA-mediated delivery of curcumin on osteosarcoma cell survival was investigated using MTS assays. To assess the effect of IMAs-delivered curcumin on osteosarcoma cell growth, fluorescence-activated cell sorting was performed. The uptake of micellar nanoassemblies was followed using confocal microscopy. Results & Discussion: IMAs-delivered curcumin is effective in blocking osteosarcoma cell growth. It decreases cell viability in human osteosarcoma (MG63, KHOS, and LM7) cells while having no effect on normal human osteoblast cells. It indicates that curcumin-loaded IMAs provide a unique delivery system targeted to osteosarcoma cells. Osteosarcoma is the most common primary bone malignancy that predominantly affects children and adolescents. Curcumin, a principal substance in the Asian spice turmeric, has been shown to block osteosarcoma cell growth. The clinical development of curcumin has been hindered due to poor aqueous solubility and thus, bioavailability, restricting its use as a drug. In this study, in order to improve the bioavailability and efficacy of curcumin, the drug was loaded (solubilized) into invertible micellar polymer nanoassemblies made from amphiphilic invertible polymers.